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Ha HT, Liu S, Nguyen XT, Vo LK, Leong NC, Nguyen DT, Balamurugan S, Lim PY, Wu Y, Seong E, Nguyen TQ, Oh J, Wenk MR, Cazenave-Gassiot A, Yapici Z, Ong WY, Burmeister M, Nguyen LN. Lack of SPNS1 results in accumulation of lysolipids and lysosomal storage disease in mouse models. JCI Insight 2024; 9:e175462. [PMID: 38451736 DOI: 10.1172/jci.insight.175462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 03/05/2024] [Indexed: 03/09/2024] Open
Abstract
Accumulation of sphingolipids, especially sphingosines, in the lysosomes is a key driver of several lysosomal storage diseases. The transport mechanism for sphingolipids from the lysosome remains unclear. Here, we identified SPNS1, which shares the highest homology to SPNS2, a sphingosine-1-phosphate (S1P) transporter, functions as a transporter for lysolipids from the lysosome. We generated Spns1-KO cells and mice and employed lipidomic and metabolomic approaches to reveal SPNS1 ligand identity. Global KO of Spns1 caused embryonic lethality between E12.5 and E13.5 and an accumulation of sphingosine, lysophosphatidylcholines (LPC), and lysophosphatidylethanolamines (LPE) in the fetal livers. Similarly, metabolomic analysis of livers from postnatal Spns1-KO mice presented an accumulation of sphingosines and lysoglycerophospholipids including LPC and LPE. Subsequently, biochemical assays showed that SPNS1 is required for LPC and sphingosine release from lysosomes. The accumulation of these lysolipids in the lysosomes of Spns1-KO mice affected liver functions and altered the PI3K/AKT signaling pathway. Furthermore, we identified 3 human siblings with a homozygous variant in the SPNS1 gene. These patients suffer from developmental delay, neurological impairment, intellectual disability, and cerebellar hypoplasia. These results reveal a critical role of SPNS1 as a promiscuous lysolipid transporter in the lysosomes and link its physiological functions with lysosomal storage diseases.
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Affiliation(s)
- Hoa Tt Ha
- Department of Biochemistry, Yong Loo Lin School of Medicine
| | - SiYi Liu
- Department of Biochemistry, Yong Loo Lin School of Medicine
| | - Xuan Ta Nguyen
- Department of Biochemistry, Yong Loo Lin School of Medicine
| | - Linh K Vo
- Department of Biochemistry, Yong Loo Lin School of Medicine
| | - Nancy Cp Leong
- Department of Biochemistry, Yong Loo Lin School of Medicine
| | - Dat T Nguyen
- Department of Biochemistry, Yong Loo Lin School of Medicine
| | | | - Pei Yen Lim
- Department of Biochemistry, Yong Loo Lin School of Medicine
- Singapore Lipidomics Incubator (SLING), Life Sciences Institute, and
| | - YaJun Wu
- Department of Anatomy, Yong Loo-Lin School of Medicine, National University of Singapore, Singapore
| | - Eunju Seong
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, USA
| | - Toan Q Nguyen
- Department of Biochemistry, Yong Loo Lin School of Medicine
| | - Jeongah Oh
- Department of Biochemistry, Yong Loo Lin School of Medicine
- Singapore Lipidomics Incubator (SLING), Life Sciences Institute, and
| | - Markus R Wenk
- Department of Biochemistry, Yong Loo Lin School of Medicine
- Singapore Lipidomics Incubator (SLING), Life Sciences Institute, and
| | - Amaury Cazenave-Gassiot
- Department of Biochemistry, Yong Loo Lin School of Medicine
- Singapore Lipidomics Incubator (SLING), Life Sciences Institute, and
| | - Zuhal Yapici
- Department of Neurology, Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo-Lin School of Medicine, National University of Singapore, Singapore
| | - Margit Burmeister
- Michigan Neuroscience Institute, University of Michigan, Ann Arbor, USA
- Departments of Computational Medicine and Biochemistry, Psychiatry, and Human Genetics, University of Michigan, Ann Arbor, USA
| | - Long N Nguyen
- Department of Biochemistry, Yong Loo Lin School of Medicine
- Singapore Lipidomics Incubator (SLING), Life Sciences Institute, and
- Cardiovascular Disease Research (CVD) Programme, Yong Loo Lin School of Medicine
- Immunology Program, Life Sciences Institute, and
- Immunology Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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2
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Farooqui AA, Farooqui T, Sun GY, Lin TN, Teh DBL, Ong WY. COVID-19, Blood Lipid Changes, and Thrombosis. Biomedicines 2023; 11:biomedicines11041181. [PMID: 37189799 DOI: 10.3390/biomedicines11041181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/12/2023] [Accepted: 04/13/2023] [Indexed: 05/17/2023] Open
Abstract
Although there is increasing evidence that oxidative stress and inflammation induced by COVID-19 may contribute to increased risk and severity of thromboses, the underlying mechanism(s) remain to be understood. The purpose of this review is to highlight the role of blood lipids in association with thrombosis events observed in COVID-19 patients. Among different types of phospholipases A2 that target cell membrane phospholipids, there is increasing focus on the inflammatory secretory phospholipase A2 IIA (sPLA2-IIA), which is associated with the severity of COVID-19. Analysis indicates increased sPLA2-IIA levels together with eicosanoids in the sera of COVID patients. sPLA2 could metabolise phospholipids in platelets, erythrocytes, and endothelial cells to produce arachidonic acid (ARA) and lysophospholipids. Arachidonic acid in platelets is metabolised to prostaglandin H2 and thromboxane A2, known for their pro-coagulation and vasoconstrictive properties. Lysophospholipids, such as lysophosphatidylcholine, could be metabolised by autotaxin (ATX) and further converted to lysophosphatidic acid (LPA). Increased ATX has been found in the serum of patients with COVID-19, and LPA has recently been found to induce NETosis, a clotting mechanism triggered by the release of extracellular fibres from neutrophils and a key feature of the COVID-19 hypercoagulable state. PLA2 could also catalyse the formation of platelet activating factor (PAF) from membrane ether phospholipids. Many of the above lipid mediators are increased in the blood of patients with COVID-19. Together, findings from analyses of blood lipids in COVID-19 patients suggest an important role for metabolites of sPLA2-IIA in COVID-19-associated coagulopathy (CAC).
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Affiliation(s)
- Akhlaq A Farooqui
- Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, OH 43210, USA
| | - Tahira Farooqui
- Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, OH 43210, USA
| | - Grace Y Sun
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA
| | - Teng-Nan Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11929, Taiwan
| | - Daniel B L Teh
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore
- Neurobiology Research Programme, Life Sciences Institute, National University of Singapore, Singapore 119260, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore
- Neurobiology Research Programme, Life Sciences Institute, National University of Singapore, Singapore 119260, Singapore
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3
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Ong WY, Leow DMK, Herr DR, Yeo CJJ. What Do Randomized Controlled Trials Inform Us About Potential Disease-Modifying Strategies for Parkinson's Disease? Neuromolecular Med 2023; 25:1-13. [PMID: 35776238 DOI: 10.1007/s12017-022-08718-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 06/05/2022] [Indexed: 01/09/2023]
Abstract
Research advances have shed new insight into cellular pathways contributing to PD pathogenesis and offer increasingly compelling therapeutic targets. In this review, we made a broad survey of the published literature that report possible disease-modifying effects on PD. While there are many studies that demonstrate benefits for various therapies for PD in animal and human studies, we confined our search to human "randomised controlled trials" and with the key words "neuroprotection" or "disease-modifying". It is hoped that through studying the results of these trials, we might clarify possible mechanisms that underlie idiopathic PD. This contrasts with studying the effect of pathophysiology of familial PD, which could be carried out by gene knockouts and animal models. Randomised controlled trials indicate promising effects of MAO-B inhibitors, dopamine agonists, NMDA receptor antagonists, metabotropic glutamate receptor antagonists, therapies related to improving glucose utilization and energy production, therapies related to reduction of excitotoxicity and oxidative stress, statin use, therapies related to iron chelation, therapies related to the use of phytochemicals, and therapies related to physical exercise and brain reward pathway on slowing PD progression. Cumulatively, these approaches fall into two categories: direct enhancement of dopaminergic signalling, and reduction of neurodegeneration. Overlaps between the two categories result in challenges in distinguishing between symptomatic versus disease-modifying effects with current clinical trial designs. Nevertheless, a broad-based approach allows us to consider all possible therapeutic avenues which may be neuroprotective. While the traditional standard of care focuses on symptomatic management with dopaminergic drugs, more recent approaches suggest ways to preserve dopaminergic neurons by attenuating excitotoxicity and oxidative stress.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.
| | - Damien Meng-Kiat Leow
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Crystal Jing-Jing Yeo
- Institute of Molecular and Cell Biology, A*Star, Singapore, 138673, Singapore
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Evanston, IL, USA
- LKC School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
- School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen, UK
- National Neuroscience Institute, Singapore, 308433, Singapore
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4
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Abstract
The SARS-CoV-2 virus gains entry to cells by binding to angiotensin-converting enzyme 2 (ACE2). Since circumventricular organs and parts of the hypothalamus lack a blood-brain barrier, and immunohistochemical studies demonstrate that ACE2 is highly expressed in circumventricular organs which are intimately connected to the hypothalamus, and the hypothalamus itself, these might be easy entry points for SARS-CoV-2 into the brain via the circulation. High ACE2 protein expression is found in the subfornical organ, area postrema, and the paraventricular nucleus of the hypothalamus (PVH). The subfornical organ and PVH are parts of a circuit to regulate osmolarity in the blood, through the secretion of anti-diuretic hormone into the posterior pituitary. The PVH is also the stress response centre in the brain. It controls not only pre-ganglionic sympathetic neurons, but is also a source of corticotropin-releasing hormone, that induces the secretion of adrenocorticotropic hormone from the anterior pituitary. It is proposed that the function of ACE2 in the circumventricular organs and the PVH could be diminished by binding with SARS-CoV-2, thus leading to a reduction in the ACE2/Ang (1-7)/Mas receptor (MasR) signalling axis, that modulates ACE/Ang II/AT1R signalling. This could result in increased presympathetic activity/neuroendocrine secretion from the PVH, and effects on the hypothalamic-pituitary-adrenal axis activity. Besides the bloodstream, the hypothalamus might also be affected by SARS-CoV-2 via transneuronal spread along the olfactory/limbic pathways. Exploring potential therapeutic pathways to prevent or attenuate neurological symptoms of COVID-19, including drugs which modulate ACE signalling, remains an important area of unmet medical need.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology Research Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore.
| | - R L Satish
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Deron R Herr
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore
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Ong WY, Herr DR, Sun GY, Lin TN. Anti-Inflammatory Effects of Phytochemical Components of Clinacanthus nutans. Molecules 2022; 27:molecules27113607. [PMID: 35684542 PMCID: PMC9182488 DOI: 10.3390/molecules27113607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/02/2022] [Accepted: 06/02/2022] [Indexed: 02/01/2023] Open
Abstract
Recent studies on the ethnomedicinal use of Clinacanthus nutans suggest promising anti-inflammatory, anti-tumorigenic, and antiviral properties for this plant. Extraction of the leaves with polar and nonpolar solvents has yielded many C-glycosyl flavones, including schaftoside, isoorientin, orientin, isovitexin, and vitexin. Aside from studies with different extracts, there is increasing interest to understand the properties of these components, especially regarding their ability to exert anti-inflammatory effects on cells and tissues. A major focus for this review is to obtain information on the effects of C. nutans extracts and its phytochemical components on inflammatory signaling pathways in the peripheral and central nervous system. Particular emphasis is placed on their role to target the Toll-like receptor 4 (TLR4)-NF-kB pathway and pro-inflammatory cytokines, the antioxidant defense pathway involving nuclear factor erythroid-2-related factor 2 (NRF2) and heme oxygenase 1 (HO-1); and the phospholipase A2 (PLA2) pathway linking to cyclooxygenase-2 (COX-2) and production of eicosanoids. The ability to provide a better understanding of the molecular targets and mechanism of action of C. nutans extracts and their phytochemical components should encourage future studies to develop new therapeutic strategies for better use of this herb to combat inflammatory diseases.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy and Neurobiology Research Programme, National University of Singapore, Singapore 119260, Singapore
- Correspondence:
| | - Deron R. Herr
- Department of Pharmacology, National University of Singapore, Singapore 119260, Singapore;
| | - Grace Y. Sun
- Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA;
| | - Teng-Nan Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529, Taiwan;
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6
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Soh S, Ong WY. Effect of Withanolide A on 7-Ketocholesterol Induced Cytotoxicity in hCMEC/D3 Brain Endothelial Cells. Cells 2022; 11:cells11030457. [PMID: 35159267 PMCID: PMC8834337 DOI: 10.3390/cells11030457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/14/2022] [Accepted: 01/24/2022] [Indexed: 11/21/2022] Open
Abstract
Withanolide A is a naturally occurring phytochemical that is found in Ashwagandha (Withania somnifera, fam. Solanaceae) or Indian Ginseng. In the current study, we elucidated the effect of withanolide A on 7-ketocholesterol (7KC) induced injury in hCMEC/D3 human brain endothelial cells. 7KC is a cholesterol oxidation product or oxysterol that is present in atherosclerotic plaques and is elevated in the plasma of patients with hypercholesterolemia and/or diabetes mellitus. Results showed that withanolide A significantly reduced the effects of 7KC, which include loss of endothelial cell viability, increase in expression of pro-inflammatory genes-IL-1β, IL-6, IL-8, TNF-α, cyclooxygenase-2 (COX-2), increased COX-2 enzyme activity, increased ROS formation, increased expression of inducible nitric oxide synthase and genes associated with blood clotting, including Factor 2/thrombin, Factor 8, von Willebrand factor, and thromboxane A synthase, and increased human thrombin enzyme activity. Some of the above effects of withanolide A on 7KC were reduced in the presence of the glucocorticoid receptor antagonist, mifepristone (RU486). These findings suggest that the glucocorticoid receptor could play a role in the cytoprotective, antioxidant, and anti-clotting effects of withanolide A against 7KC. Further studies are necessary to elucidate the detailed mechanisms of action of withanolide A against oxysterol-induced injury.
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Affiliation(s)
- Sandra Soh
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore;
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore;
- Neurobiology Research Programme, Life Sciences Institute, National University of Singapore, Singapore 119260, Singapore
- Correspondence:
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7
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Jo J, Yang L, Tran HD, Yu W, Sun AX, Chang YY, Jung BC, Lee SJ, Saw TY, Xiao B, Khoo ATT, Yaw LP, Xie JJ, Lokman H, Ong WY, Lim GGY, Lim KL, Tan EK, Ng HH, Je HS. Lewy Body-like Inclusions in Human Midbrain Organoids Carrying Glucocerebrosidase and α-Synuclein Mutations. Ann Neurol 2021; 90:490-505. [PMID: 34288055 PMCID: PMC9543721 DOI: 10.1002/ana.26166] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 07/12/2021] [Accepted: 07/12/2021] [Indexed: 01/02/2023]
Abstract
Objective We utilized human midbrain‐like organoids (hMLOs) generated from human pluripotent stem cells carrying glucocerebrosidase gene (GBA1) and α‐synuclein (α‐syn; SNCA) perturbations to investigate genotype‐to‐phenotype relationships in Parkinson disease, with the particular aim of recapitulating α‐syn– and Lewy body–related pathologies and the process of neurodegeneration in the hMLO model. Methods We generated and characterized hMLOs from GBA1−/− and SNCA overexpressing isogenic embryonic stem cells and also generated Lewy body–like inclusions in GBA1/SNCA dual perturbation hMLOs and conduritol‐b‐epoxide–treated SNCA triplication hMLOs. Results We identified for the first time that the loss of glucocerebrosidase, coupled with wild‐type α‐syn overexpression, results in a substantial accumulation of detergent‐resistant, β‐sheet–rich α‐syn aggregates and Lewy body–like inclusions in hMLOs. These Lewy body–like inclusions exhibit a spherically symmetric morphology with an eosinophilic core, containing α‐syn with ubiquitin, and can also be formed in Parkinson disease patient–derived hMLOs. We also demonstrate that impaired glucocerebrosidase function promotes the formation of Lewy body–like inclusions in hMLOs derived from patients carrying the SNCA triplication. Interpretation Taken together, the data indicate that our hMLOs harboring 2 major risk factors (glucocerebrosidase deficiency and wild‐type α‐syn overproduction) of Parkinson disease provide a tractable model to further elucidate the underlying mechanisms for progressive Lewy body formation. ANN NEUROL 2021;90:490–505
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Affiliation(s)
- Junghyun Jo
- Genome Institute of Singapore, Singapore, Singapore.,Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Lin Yang
- Genome Institute of Singapore, Singapore, Singapore
| | - Hoang-Dai Tran
- Genome Institute of Singapore, Singapore, Singapore.,National Neuroscience Institute, Singapore, Singapore
| | - Weonjin Yu
- Program in Neuroscience and Behavioral Disorders, Duke-NUS Medical School, Singapore, Singapore.,Department of Physiology, Seoul National University College of Medicine, Seoul, South Korea
| | - Alfred Xuyang Sun
- Genome Institute of Singapore, Singapore, Singapore.,National Neuroscience Institute, Singapore, Singapore.,Program in Neuroscience and Behavioral Disorders, Duke-NUS Medical School, Singapore, Singapore
| | - Ya Yin Chang
- National Neuroscience Institute, Singapore, Singapore
| | - Byung Chul Jung
- Department of Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, South Korea.,Department of Biomedical Laboratory Science, Masan University, Changwon-si, South Korea
| | - Seung-Jae Lee
- Department of Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, South Korea
| | | | - Bin Xiao
- National Neuroscience Institute, Singapore, Singapore
| | - Audrey Tze Ting Khoo
- Program in Neuroscience and Behavioral Disorders, Duke-NUS Medical School, Singapore, Singapore
| | - Lai-Ping Yaw
- Genome Institute of Singapore, Singapore, Singapore
| | | | - Hidayat Lokman
- Program in Neuroscience and Behavioral Disorders, Duke-NUS Medical School, Singapore, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, Singapore
| | | | - Kah-Leong Lim
- National Neuroscience Institute, Singapore, Singapore.,Program in Neuroscience and Behavioral Disorders, Duke-NUS Medical School, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Eng-King Tan
- National Neuroscience Institute, Singapore, Singapore
| | - Huck-Hui Ng
- Genome Institute of Singapore, Singapore, Singapore.,Department of Biochemistry, National University of Singapore, Singapore, Singapore.,Department of Biological Sciences, National University of Singapore, Singapore, Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Hyunsoo Shawn Je
- Program in Neuroscience and Behavioral Disorders, Duke-NUS Medical School, Singapore, Singapore
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8
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Xiang P, Chew WS, Seow WL, Lam BWS, Ong WY, Herr DR. The S1P 2 receptor regulates blood-brain barrier integrity and leukocyte extravasation with implications for neurodegenerative disease. Neurochem Int 2021; 146:105018. [PMID: 33727061 DOI: 10.1016/j.neuint.2021.105018] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 03/04/2021] [Accepted: 03/07/2021] [Indexed: 01/08/2023]
Abstract
Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid which modulates vascular integrity through its receptors, S1P1-S1P5. Notably, S1P2 has been shown to mediate the disruption of cerebrovascular integrity in vitro and in vivo. However, the mechanism underlying this process has not been fully elucidated. We evaluated the role of S1P2 in blood-brain barrier (BBB) disruption induced by lipopolysaccharide (LPS)-mediated systemic inflammation and found that BBB disruption and neutrophil infiltration were significantly attenuated in S1pr2-/- mice relative to S1pr2+/- littermates. This is concomitant with attenuation of LPS-induced transcriptional activation of IL-6 and downregulation of occludin. Furthermore, S1pr2-/- mice had significantly reduced expression of genes essential for neutrophil infiltration: Sele, Cxcl1, and Cxcl2. Conversely, pharmacological agonism of S1P2 induced transcriptional activation of E-selectin in vitro and in vivo. Although S1P2 does not appear to be required for activation of microglia, stimulation of microglial cells with the S1P2 potentiated the response of endothelial cells to LPS. These results demonstrate that S1P2 promotes LPS-induced neutrophil extravasation by inducing expression of endothelial adhesion molecule gene, Sele, and potentiating microglial inflammation of endothelial cells. It is likely that S1P2 is a mediator of cerebrovascular inflammation and represents a potential therapeutic target for neurodegenerative disease such as vascular cognitive impairment.
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Affiliation(s)
- Ping Xiang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Wee Siong Chew
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Wei Lun Seow
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore
| | - Brenda Wan Shing Lam
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Biology, San Diego State University, San Diego, CA, 92182, USA; American University of Health Sciences, Long Beach, CA, 90755, USA.
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9
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Gunaseelan S, Wang Z, Tong VKJ, Ming SWS, Razar RBBA, Srimasorn S, Ong WY, Lim KL, Chua JJE. Loss of FEZ1, a gene deleted in Jacobsen syndrome, causes locomotion defects and early mortality by impairing motor neuron development. Hum Mol Genet 2021; 30:5-20. [PMID: 33395696 DOI: 10.1093/hmg/ddaa281] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/10/2020] [Accepted: 12/23/2020] [Indexed: 01/05/2023] Open
Abstract
FEZ1-mediated axonal transport plays important roles in central nervous system development but its involvement in the peripheral nervous system is not well-characterized. FEZ1 is deleted in Jacobsen syndrome (JS), an 11q terminal deletion developmental disorder. JS patients display impaired psychomotor skills, including gross and fine motor delay, suggesting that FEZ1 deletion may be responsible for these phenotypes, given its association with the development of motor-related circuits. Supporting this hypothesis, our data show that FEZ1 is selectively expressed in the rat brain and spinal cord. Its levels progressively increase over the developmental course of human motor neurons (MN) derived from embryonic stem cells. Deletion of FEZ1 strongly impaired axon and dendrite development, and significantly delayed the transport of synaptic proteins into developing neurites. Concurring with these observations, Drosophila unc-76 mutants showed severe locomotion impairments, accompanied by a strong reduction of synaptic boutons at neuromuscular junctions. These abnormalities were ameliorated by pharmacological activation of UNC-51/ATG1, a FEZ1-activating kinase, with rapamycin and metformin. Collectively, the results highlight a role for FEZ1 in MN development and implicate its deletion as an underlying cause of motor impairments in JS patients.
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Affiliation(s)
- Saravanan Gunaseelan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Ziyin Wang
- National Neuroscience Institute, Singapore, Singapore
| | - Venetia Kok Jing Tong
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,National Neuroscience Institute, Singapore, Singapore
| | - Sylvester Wong Shu Ming
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | | | - Sumitra Srimasorn
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Kah-Leong Lim
- National Neuroscience Institute, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - John Jia En Chua
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,LSI Neurobiology Programme, National University of Singapore, Singapore, Singapore.,Healthy Longevity Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Institute for Health Innovation and Technology, National University of Singapore, Singapore, Singapore.,Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore
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10
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Lam BWS, Yam TYA, Chen CP, Lai MKP, Ong WY, Herr DR. The noncanonical chronicles: Emerging roles of sphingolipid structural variants. Cell Signal 2020; 79:109890. [PMID: 33359087 DOI: 10.1016/j.cellsig.2020.109890] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 02/08/2023]
Abstract
Sphingolipids (SPs) are structurally diverse and represent one of the most quantitatively abundant classes of lipids in mammalian cells. In addition to their structural roles, many SP species are known to be bioactive mediators of essential cellular processes. Historically, studies have focused on SP species that contain the canonical 18‑carbon, mono-unsaturated sphingoid backbone. However, increasingly sensitive analytical technologies, driven by advances in mass spectrometry, have facilitated the identification of previously under-appreciated, molecularly distinct SP species. Many of these less abundant species contain noncanonical backbones. Interestingly, a growing number of studies have identified clinical associations between these noncanonical SPs and disease, suggesting that there is functional significance to the alteration of SP backbone structure. For example, associations have been found between SP chain length and cardiovascular disease, pain, diabetes, and dementia. This review will provide an overview of the processes that are known to regulate noncanonical SP accumulation, describe the clinical correlations reported for these molecules, and review the experimental evidence for the potential functional implications of their dysregulation. It is likely that further scrutiny of noncanonical SPs may provide new insight into pathophysiological processes, serve as useful biomarkers for disease, and lead to the design of novel therapeutic strategies.
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Affiliation(s)
- Brenda Wan Shing Lam
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ting Yu Amelia Yam
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Christopher P Chen
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Memory Aging and Cognition Centre, Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Mitchell K P Lai
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Memory Aging and Cognition Centre, Department of Psychological Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; Department of Biology, San Diego State University, San Diego, CA, USA; American University of Health Sciences, Long Beach, CA, USA.
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11
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Chua XY, Ho LTY, Xiang P, Chew WS, Lam BWS, Chen CP, Ong WY, Lai MKP, Herr DR. Preclinical and Clinical Evidence for the Involvement of Sphingosine 1-Phosphate Signaling in the Pathophysiology of Vascular Cognitive Impairment. Neuromolecular Med 2020; 23:47-67. [PMID: 33180310 DOI: 10.1007/s12017-020-08632-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Accepted: 11/03/2020] [Indexed: 02/07/2023]
Abstract
Sphingosine 1-phosphates (S1Ps) are bioactive lipids that mediate a diverse range of effects through the activation of cognate receptors, S1P1-S1P5. Scrutiny of S1P-regulated pathways over the past three decades has identified important and occasionally counteracting functions in the brain and cerebrovascular system. For example, while S1P1 and S1P3 mediate proinflammatory effects on glial cells and directly promote endothelial cell barrier integrity, S1P2 is anti-inflammatory but disrupts barrier integrity. Cumulatively, there is significant preclinical evidence implicating critical roles for this pathway in regulating processes that drive cerebrovascular disease and vascular dementia, both being part of the continuum of vascular cognitive impairment (VCI). This is supported by clinical studies that have identified correlations between alterations of S1P and cognitive deficits. We review studies which proposed and evaluated potential mechanisms by which such alterations contribute to pathological S1P signaling that leads to VCI-associated chronic neuroinflammation and neurodegeneration. Notably, S1P receptors have divergent but overlapping expression patterns and demonstrate complex interactions. Therefore, the net effect produced by S1P represents the cumulative contributions of S1P receptors acting additively, synergistically, or antagonistically on the neural, vascular, and immune cells of the brain. Ultimately, an optimized therapeutic strategy that targets S1P signaling will have to consider these complex interactions.
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Affiliation(s)
- Xin Ying Chua
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Leona T Y Ho
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Ping Xiang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Wee Siong Chew
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Brenda Wan Shing Lam
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Christopher P Chen
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- Memory Aging and Cognition Centre, National University Health System, Kent Ridge, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
- Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore
| | - Mitchell K P Lai
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Memory Aging and Cognition Centre, National University Health System, Kent Ridge, Singapore.
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Department of Biology, San Diego State University, San Diego, CA, USA.
- American University of Health Sciences, Long Beach, CA, USA.
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12
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Kuo X, Herr DR, Ong WY. Anti-inflammatory and Cytoprotective Effect of Clinacanthus nutans Leaf But Not Stem Extracts on 7-Ketocholesterol Induced Brain Endothelial Cell Injury. Neuromolecular Med 2020; 23:176-183. [PMID: 33085066 DOI: 10.1007/s12017-020-08621-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 10/08/2020] [Indexed: 12/16/2022]
Abstract
Clinacanthus nutans (Lindau) (C. nutans) has diverse uses in traditional herbal medicine for treating skin rashes, insect and snake bites, lesions caused by herpes simplex virus, diabetes mellitus and gout in Singapore, Malaysia, Indonesia, Thailand and China. We previously showed that C. nutans has the ability to modulate the induction of cytosolic phospholipase A2 (cPLA2) expression in SH-SY5Y cells through the inhibition of histone deacetylases (HDACs). In the current study, we elucidated the effect of C. nutans on the hCMEC/D3 human brain endothelial cell line. Endothelial cells are exposed to high levels of the cholesterol oxidation product, 7-ketocholesterol (7KC), in patients with cardiovascular disease and diabetes, and this process is thought to mediate pathological inflammation. 7KC induced a dose-dependent loss of hCMEC/D3 cell viability, and such damage was significantly inhibited by C. nutans leaf extracts but not stem extracts. 7KC also induced a marked increase in mRNA expression of pro-inflammatory cytokines, IL-1β IL-6, IL-8, TNF-α and cyclooxygenase-2 (COX-2) in brain endothelial cells, and these increases were significantly inhibited by C. nutans leaf but not stem extracts. HPLC analyses showed that leaf extracts have a markedly different chemical profile compared to stem extracts, which might explain their different effects in counteracting 7KC-induced inflammation. Further study is necessary to identify the putative phytochemicals in C. nutans leaves that have anti-inflammatory properties.
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Affiliation(s)
- Xuan Kuo
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Deron R Herr
- Department of Biology, San Diego State University, San Diego, CA, 92182, USA.
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore.
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13
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Kao MH, Wu JS, Cheung WM, Chen JJ, Sun GY, Ong WY, Herr DR, Lin TN. Clinacanthus nutans Mitigates Neuronal Death and Reduces Ischemic Brain Injury: Role of NF-κB-driven IL-1β Transcription. Neuromolecular Med 2020; 23:199-210. [PMID: 33025396 DOI: 10.1007/s12017-020-08618-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 09/26/2020] [Indexed: 12/15/2022]
Abstract
Neuroinflammation has been shown to exacerbate ischemic brain injury, and is considered as a prime target for the development of stroke therapies. Clinacanthus nutans Lindau (C. nutans) is widely used in traditional medicine for treating insect bites, viral infection and cancer, due largely to its anti-oxidative and anti-inflammatory properties. Recently, we reported that an ethanol extract from the leaf of C. nutans could protect the brain against ischemia-triggered neuronal death and infarction. In order to further understand the molecular mechanism(s) for its beneficial effects, two experimental paradigms, namely, in vitro primary cortical neurons subjected to oxygen-glucose deprivation (OGD) and in vivo rat middle cerebral artery (MCA) occlusion, were used to dissect the anti-inflammatory effects of C. nutans extract. Using promoter assays, immunofluorescence staining, and loss-of-function (siRNA) approaches, we demonstrated that transient OGD led to marked induction of IL-1β, IL-6 and TNFα, while pretreatment with C. nutans suppressed production of inflammatory cytokines in primary neurons. C. nutans inhibited IL-1β transcription via preventing NF-κB/p65 nuclear translocation, and siRNA knockdown of either p65 or IL-1β mitigated OGD-mediated neuronal death. Correspondingly, post-ischemic treatment of C. nutans attenuated IκBα degradation and decreased IL-1β, IL-6 and TNFα production in the ischemic brain. Furthermore, IL-1β siRNA post-ischemic treatment reduced cerebral infarct, thus mimicking the beneficial effects of C. nutans. In summary, our findings demonstrated the ability for C. nutans to suppress NF-κB nuclear translocation and inhibit IL-1β transcription in ischemic models. Results further suggest the possibility for using C. nutans to prevent and treat stroke patients.
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Affiliation(s)
- Mei-Han Kao
- Taiwan International Graduate Program in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan
| | - Jui-Sheng Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, ROC
| | - Wai-Mui Cheung
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, ROC
| | - Jin-Jer Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, ROC
| | - Grace Y Sun
- Department of Biochemistry, University of Missouri, Columbia, USA
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.,Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Teng-Nan Lin
- Taiwan International Graduate Program in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan. .,Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, ROC.
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14
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Ong WY, Go ML, Wang DY, Cheah IKM, Halliwell B. Effects of Antimalarial Drugs on Neuroinflammation-Potential Use for Treatment of COVID-19-Related Neurologic Complications. Mol Neurobiol 2020; 58:106-117. [PMID: 32897518 PMCID: PMC7477069 DOI: 10.1007/s12035-020-02093-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/25/2020] [Indexed: 02/06/2023]
Abstract
The SARS-CoV-2 virus that is the cause of coronavirus disease 2019 (COVID-19) affects not only peripheral organs such as the lungs and blood vessels, but also the central nervous system (CNS)—as seen by effects on smell, taste, seizures, stroke, neuropathological findings and possibly, loss of control of respiration resulting in silent hypoxemia. COVID-19 induces an inflammatory response and, in severe cases, a cytokine storm that can damage the CNS. Antimalarials have unique properties that distinguish them from other anti-inflammatory drugs. (A) They are very lipophilic, which enhances their ability to cross the blood-brain barrier (BBB). Hence, they have the potential to act not only in the periphery but also in the CNS, and could be a useful addition to our limited armamentarium against the SARS-CoV-2 virus. (B) They are non-selective inhibitors of phospholipase A2 isoforms, including cytosolic phospholipase A2 (cPLA2). The latter is not only activated by cytokines but itself generates arachidonic acid, which is metabolized by cyclooxygenase (COX) to pro-inflammatory eicosanoids. Free radicals are produced in this process, which can lead to oxidative damage to the CNS. There are at least 4 ways that antimalarials could be useful in combating COVID-19. (1) They inhibit PLA2. (2) They are basic molecules capable of affecting the pH of lysosomes and inhibiting the activity of lysosomal enzymes. (3) They may affect the expression and Fe2+/H+ symporter activity of iron transporters such as divalent metal transporter 1 (DMT1), hence reducing iron accumulation in tissues and iron-catalysed free radical formation. (4) They could affect viral replication. The latter may be related to their effect on inhibition of PLA2 isoforms. Inhibition of cPLA2 impairs an early step of coronavirus replication in cell culture. In addition, a secretory PLA2 (sPLA2) isoform, PLA2G2D, has been shown to be essential for the lethality of SARS-CoV in mice. It is important to take note of what ongoing clinical trials on chloroquine and hydroxychloroquine can eventually tell us about the use of antimalarials and other anti-inflammatory agents, not only for the treatment of COVID-19, but also for neurovascular disorders such as stroke and vascular dementia.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore.
| | - Mei-Lin Go
- Department of Pharmacy, Faculty of Science, National University of Singapore, Singapore, 119260, Singapore
| | - De-Yun Wang
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Irwin Kee-Mun Cheah
- Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Barry Halliwell
- Neurobiology Programme, Life Sciences Institute, National University of Singapore, Singapore, 119260, Singapore.
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.
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15
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Teh DBL, Bansal A, Chai C, Toh TB, Tucker RAJ, Gammad GGL, Yeo Y, Lei Z, Zheng X, Yang F, Ho JS, Bolem N, Wu BC, Gnanasammandhan MK, Hooi L, Dawe GS, Libedinsky C, Ong WY, Halliwell B, Chow EKH, Lim KL, Zhang Y, Kennedy BK. A Flexi-PEGDA Upconversion Implant for Wireless Brain Photodynamic Therapy. Adv Mater 2020; 32:e2001459. [PMID: 32484308 DOI: 10.1002/adma.202001459] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 04/18/2020] [Accepted: 04/20/2020] [Indexed: 05/12/2023]
Abstract
Near-infrared (NIR) activatable upconversion nanoparticles (UCNPs) enable wireless-based phototherapies by converting deep-tissue-penetrating NIR to visible light. UCNPs are therefore ideal as wireless transducers for photodynamic therapy (PDT) of deep-sited tumors. However, the retention of unsequestered UCNPs in tissue with minimal options for removal limits their clinical translation. To address this shortcoming, biocompatible UCNPs implants are developed to deliver upconversion photonic properties in a flexible, optical guide design. To enhance its translatability, the UCNPs implant is constructed with an FDA-approved poly(ethylene glycol) diacrylate (PEGDA) core clad with fluorinated ethylene propylene (FEP). The emission spectrum of the UCNPs implant can be tuned to overlap with the absorption spectra of the clinically relevant photosensitizer, 5-aminolevulinic acid (5-ALA). The UCNPs implant can wirelessly transmit upconverted visible light till 8 cm in length and in a bendable manner even when implanted underneath the skin or scalp. With this system, it is demonstrated that NIR-based chronic PDT is achievable in an untethered and noninvasive manner in a mouse xenograft glioblastoma multiforme (GBM) model. It is postulated that such encapsulated UCNPs implants represent a translational shift for wireless deep-tissue phototherapy by enabling sequestration of UCNPs without compromising wireless deep-tissue light delivery.
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Affiliation(s)
- Daniel Boon Loong Teh
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117456, Singapore
| | - Akshaya Bansal
- Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Chou Chai
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117456, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Tan Boon Toh
- The N.1 Institute for Health, National University of Singapore, Singapore, 117599, Singapore
| | - Robert Alan Jappy Tucker
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117456, Singapore
| | - Gil Gerald Lasam Gammad
- The N.1 Institute for Health, National University of Singapore, Singapore, 117599, Singapore
| | - Yanzhuang Yeo
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Zhendong Lei
- Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore, 117583, Singapore
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, 117456, Singapore
| | - Xiang Zheng
- Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore, 117583, Singapore
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, 117456, Singapore
| | - Fengyuan Yang
- Department of Electrical & Computer Engineering, Faculty of Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - John S Ho
- The N.1 Institute for Health, National University of Singapore, Singapore, 117599, Singapore
- Department of Electrical & Computer Engineering, Faculty of Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Nagarjun Bolem
- Division of Neurosurgery, National University Hospital, Singapore, 119228, Singapore
| | - Bing Cheng Wu
- Department of Pathology, National University Hospital, Singapore, 119228, Singapore
| | - Muthu Kumar Gnanasammandhan
- Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Lissa Hooi
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore
| | - Gavin Stewart Dawe
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Singapore
| | - Camilo Libedinsky
- The N.1 Institute for Health, National University of Singapore, Singapore, 117599, Singapore
- Department of Psychology, Faculty of Arts and Social Sciences, National University of Singapore, Singapore, 117570, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117594, Singapore
| | - Barry Halliwell
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117456, Singapore
| | - Edward Kai-Hua Chow
- The N.1 Institute for Health, National University of Singapore, Singapore, 117599, Singapore
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, 117599, Singapore
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117600, Singapore
| | - Kah-Leong Lim
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117456, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, 308232, Singapore
| | - Yong Zhang
- Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore, Singapore, 117583, Singapore
| | - Brian K Kennedy
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117456, Singapore
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117456, Singapore
- Center for Healthy Ageing, National University Health System, Singapore, 119228, Singapore
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16
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Herr DR, Yam TYA, Tan WSD, Koh SS, Wong WSF, Ong WY, Chayaburakul K. Ultrastructural Characteristics of DHA-Induced Pyroptosis. Neuromolecular Med 2020; 22:293-303. [PMID: 31902115 PMCID: PMC7230060 DOI: 10.1007/s12017-019-08586-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 12/21/2019] [Indexed: 12/26/2022]
Abstract
Microglial cells are resident macrophages of the central nervous system (CNS) that respond to bioactive lipids such as docosahexaenoic acid (DHA). Low micromolar concentrations of DHA typically promote anti-inflammatory functions of microglia, but higher concentrations result in a form of pro-inflammatory programmed cell death known as pyroptosis. This study used scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to investigate the morphological characteristics of pyroptosis in BV-2 microglial cells following exposure to 200 µM DHA. Vehicle-treated cells are characterized by extended processes, spine-like projections or 0.4 to 5.2 µm in length, and numerous extracellular vesicles (EVs) tethered to the surface of the plasma membrane. In contrast to vehicle-treated cells, gross abnormalities are observed after treating cells with 200 µM DHA for 4 h. These include the appearance of numerous pits or pores of varying sizes across the cell surface, structural collapse and flattening of the cell shape. Moreover, EVs and spines were lost following DHA treatment, possibly due to release from the cell surface. The membrane pores appear after DHA treatment initially measured ~ 30 nm, consistent with the previously reported gasdermin D (GSDMD) pore complexes. Complete collapse of cytoplasmic organization and loss of nuclear envelope integrity were also observed in DHA-treated cells. These processes are morphologically distinct from the changes that occur during cisplatin-induced apoptosis, such as the appearance of apoptotic bodies and tightly packed organelles, and the maintenance of EVs and nuclear envelope integrity. Cumulatively, this study provides a systematic description of the ultrastructural characteristics of DHA-induced pyroptosis, including distinguishing features that differentiate this process from apoptosis.
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Affiliation(s)
- Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.
| | - Ting Yu Amelia Yam
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Wan Shun Daniel Tan
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Sally Shuxian Koh
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
| | - Wai Shiu Fred Wong
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore.,Immunology Program, Life Science Institute, National University of Singapore, 28 Medical Drive, Singapore, 117456, Singapore.,Singapore-HUJ Alliance for Research and Enterprise, National University of Singapore, 1 CREATE Way, Singapore, 138602, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 119260, Singapore
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17
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Wang W, Xiang P, Chew WS, Torta F, Bandla A, Lopez V, Seow WL, Lam BWS, Chang JK, Wong P, Chayaburakul K, Ong WY, Wenk MR, Sundar R, Herr DR. Activation of sphingosine 1-phosphate receptor 2 attenuates chemotherapy-induced neuropathy. J Biol Chem 2019; 295:1143-1152. [PMID: 31882542 DOI: 10.1074/jbc.ra119.011699] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/07/2019] [Indexed: 12/11/2022] Open
Abstract
Platinum-based therapeutics are used to manage many forms of cancer, but frequently result in peripheral neuropathy. Currently, the only option available to attenuate chemotherapy-induced neuropathy is to limit or discontinue this treatment. Sphingosine 1-phosphate (S1P) is a lipid-based signaling molecule involved in neuroinflammatory processes by interacting with its five cognate receptors: S1P1-5 In this study, using a combination of drug pharmacodynamic analysis in human study participants, disease modeling in rodents, and cell-based assays, we examined whether S1P signaling may represent a potential target in the treatment of chemotherapy-induced neuropathy. To this end, we first investigated the effects of platinum-based drugs on plasma S1P levels in human cancer patients. Our analysis revealed that oxaliplatin treatment specifically increases one S1P species, d16:1 S1P, in these patients. Although d16:1 S1P is an S1P2 agonist, it has lower potency than the most abundant S1P species (d18:1 S1P). Therefore, as d16:1 S1P concentration increases, it is likely to disproportionately activate proinflammatory S1P1 signaling, shifting the balance away from S1P2 We further show that a selective S1P2 agonist, CYM-5478, reduces allodynia in a rat model of cisplatin-induced neuropathy and attenuates the associated inflammatory processes in the dorsal root ganglia, likely by activating stress-response proteins, including ATF3 and HO-1. Cumulatively, the findings of our study suggest that the development of a specific S1P2 agonist may represent a promising therapeutic approach for the management of chemotherapy-induced neuropathy.
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Affiliation(s)
- Wei Wang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Ping Xiang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Wee Siong Chew
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Federico Torta
- Singapore Lipidomics Incubator (SLING), Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Aishwarya Bandla
- The N.1 Institute for Health, National University of Singapore, Singapore 119077
| | - Violeta Lopez
- Alice Lee Centre for Nursing Studies, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Wei Lun Seow
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Brenda Wan Shing Lam
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Jing Kai Chang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Peiyan Wong
- Neuroscience Phenotyping Core, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | | | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228.,Neurobiology and Ageing Research Programme, National University of Singapore, Singapore 119077
| | - Markus R Wenk
- Singapore Lipidomics Incubator (SLING), Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228.,Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228
| | - Raghav Sundar
- The N.1 Institute for Health, National University of Singapore, Singapore 119077 .,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228.,Department of Haematology-Oncology, National University Health System, Singapore 119074
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228 .,Department of Biology, San Diego State University, San Diego, California 92182
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18
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Tan A, Babak MV, Venkatesan G, Lim C, Klotz KN, Herr DR, Cheong SL, Federico S, Spalluto G, Ong WY, Chen YZ, Loo JSE, Pastorin G. Design, Synthesis and Evaluation of New Indolylpyrimidylpiperazines for Gastrointestinal Cancer Therapy. Molecules 2019; 24:E3661. [PMID: 31614517 PMCID: PMC6832257 DOI: 10.3390/molecules24203661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 10/04/2019] [Accepted: 10/08/2019] [Indexed: 11/29/2022] Open
Abstract
Human A3 adenosine receptor hA3AR has been implicated in gastrointestinal cancer, where its cellular expression has been found increased, thus suggesting its potential as a molecular target for novel anticancer compounds. Observation made in our previous work indicated the importance of the carbonyl group of amide in the indolylpyrimidylpiperazine (IPP) for its human A2A adenosine receptor (hA2AAR) subtype binding selectivity over the other AR subtypes. Taking this observation into account, we structurally modified an indolylpyrimidylpiperazine (IPP) scaffold, 1 (a non-selective adenosine receptors' ligand) into a modified IPP (mIPP) scaffold by switching the position of the carbonyl group, resulting in the formation of both ketone and tertiary amine groups in the new scaffold. Results showed that such modification diminished the A2A activity and instead conferred hA3AR agonistic activity. Among the new mIPP derivatives (3-6), compound 4 showed potential as a hA3AR partial agonist, with an Emax of 30% and EC50 of 2.89 ± 0.55 μM. In the cytotoxicity assays, compound 4 also exhibited higher cytotoxicity against both colorectal and liver cancer cells as compared to normal cells. Overall, this new series of compounds provide a promising starting point for further development of potent and selective hA3AR partial agonists for the treatment of gastrointestinal cancers.
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Affiliation(s)
- Aaron Tan
- NUS Graduate School of Integrative Sciences and Engineering, National University of Singapore, Centre for Life Sciences, #05-01, 28 Medical Drive, Singapore 117456, Singapore.
| | - Maria V Babak
- Department of Pharmacy, National University of Singapore, Singapore 119260, Singapore.
| | | | - Clarissa Lim
- Department of Pharmacy, National University of Singapore, Singapore 119260, Singapore.
| | - Karl-Norbert Klotz
- Institut für Pharmakologie und Toxikologie, Universität Würzburg, 97078 Würzburg, Germany.
| | - Deron Raymond Herr
- Department of Pharmacology, National University of Singapore, Singapore 117600, Singapore.
| | - Siew Lee Cheong
- Department of Pharmaceutical Chemistry, School of Pharmacy, International Medical University, 126 Jalan Jalil Perkasa 19, Bukit Jalil, Kuala Lumpur 57000, Malaysia.
| | - Stephanie Federico
- Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Trieste, 34127 Trieste, Italy.
| | - Giampiero Spalluto
- Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Trieste, 34127 Trieste, Italy.
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore 119260, Singapore.
| | - Yu Zong Chen
- Department of Pharmacy, National University of Singapore, Singapore 119260, Singapore.
| | - Jason Siau Ee Loo
- School of Pharmacy, Faculty of Health and Medical Sciences, Taylor's University, 1, Jalan Taylors, Subang Jaya, Selangor 47500, Malaysia.
| | - Giorgia Pastorin
- NUS Graduate School of Integrative Sciences and Engineering, National University of Singapore, Centre for Life Sciences, #05-01, 28 Medical Drive, Singapore 117456, Singapore.
- Department of Pharmacy, National University of Singapore, Singapore 119260, Singapore.
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19
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Chew WS, Torta F, Ji S, Choi H, Begum H, Sim X, Khoo CM, Khoo EYH, Ong WY, Van Dam RM, Wenk MR, Tai ES, Herr DR. Large-scale lipidomics identifies associations between plasma sphingolipids and T2DM incidence. JCI Insight 2019; 5:126925. [PMID: 31162145 DOI: 10.1172/jci.insight.126925] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Sphingolipids (SPs) are ubiquitous, structurally diverse molecules that include ceramides, sphingomyelins, and sphingosines. They are involved in various pathologies including obesity and type 2 diabetes mellitus (T2DM). Therefore, it is likely that perturbations in plasma concentrations of SPs are associated with disease. Identifying these associations may reveal useful biomarkers or provide insight into disease processes. METHODS We performed a lipidomics evaluation of molecularly-distinct SPs in the plasma of 2,302 ethnically-Chinese Singaporeans using electrospray ionization mass spectrometry coupled with liquid chromatography. SP profiles were compared to clinical and biochemical characteristics, and subjects were evaluated by follow-up visits for 11 years. RESULTS We found that ceramides correlate positively but hexosylceramides correlate negatively with body mass index (BMI) and homeostatic model assessment of insulin resistance (HOMA-IR). Furthermore, SPs with a d16:1 sphingoid backbone correlate more positively with BMI and HOMA-IR, while d18:2 SPs correlate less positively, relative to canonical d18:1 SPs. We also found that higher concentrations of two distinct sphingomyelins were associated with a higher risk of T2DM (HR 1.45, 95% CI 1.18-1.78 for SM d16:1/C18:0; and HR 1.40, 95% CI 1.17-1.68 for SM d18:1/C18:0). CONCLUSION We identified significant associations between SPs and obesity/T2DM characteristics, specifically, that of hexosylceramides, d16:1 SPs, and d18:2 SPs. This suggests that the balance of SP metabolism, rather than ceramide accumulation, is associated with the pathology of obesity. We further identified two specific SPs that may represent prognostic biomarkers for T2DM. FUNDING Funding sources are listed in the Acknowledgements section.
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Affiliation(s)
| | - Federico Torta
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - Shanshan Ji
- Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - Hyungwon Choi
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore.,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National Health System, Singapore.,Institute of Molecular and Cell Biology, Agency for Science, Technology, and Research, Singapore
| | - Husna Begum
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - Xueling Sim
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore
| | - Chin Meng Khoo
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National Health System, Singapore
| | - Eric Yin Hao Khoo
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National Health System, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Rob M Van Dam
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore.,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National Health System, Singapore
| | - Markus R Wenk
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.,Singapore Lipidomics Incubator, Life Sciences Institute, National University of Singapore, Singapore
| | - E Shyong Tai
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore.,Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National Health System, Singapore.,Duke-NUS Graduate Medical School, Singapore
| | - Deron R Herr
- Department of Pharmacology and.,Department of Biology, San Diego State University, San Diego, California, USA
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20
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Hoong JSY, Chew WS, Torta F, Ji S, Choi H, Begum H, Sim X, Khoo CM, Khoo EYH, Ong WY, Wenk M, Tai ES, Herr D, Dam RV. Plasma Sphingolipids and Subclinical Atherosclerosis – Novel Associations Uncovered by a Large-scale Lipidomic Analysis (P18-129-19). Curr Dev Nutr 2019. [DOI: 10.1093/cdn/nzz039.p18-129-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Objectives
Sphingolipids (SP) are a diverse class of heterogenous lipids that includes ceramides, sphingomyelins, and glycosphingolipids. Many SPs have diverse roles in cell functions including cell growth, inflammation and angiogenesis, and previous studies suggest that SPs may also be involved in the pathogenesis of cardiovascular diseases. We aimed to identify plasma SPs and subsequently evaluate associations between plasma SPs and subclinical atherosclerosis in a subset of the Multiethnic Cohort of Singapore with the goal of uncovering novel biomarkers predictive of heart disease.
Methods
We conducted a lipidomics evaluation of 103 molecularly-distinct SPs in the plasma of 559 Singaporeans aged 50 years and above using electrospray ionization mass spectrometry coupled with liquid chromatography. All participants did not have a history of diabetes, heart disease, stroke or cancer at baseline, and completed a detailed health screening that evaluated risk factors for cardiovascular disease including computed tomography scans of the abdomen and coronary arteries. Multivariable logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for associations between SPs and subclinical atherosclerosis (defined as coronary artery calcium score ≥ 100).
Results
Ceramides (Cer), particularly those with a d16:1 or d18:1 backbone, were directly associated with higher risk of subclinical atherosclerosis whereas a small number of monohexosylceramides (MHCer), dihexosylceramides (DHCer) and sphingomyelins (SM) with a d18:2 sphingoid backbone were inversely associated. However most associations were attenuated after adjusting for conventional cardiovascular risk factors, including blood lipid (low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides) concentrations and glycemic markers, suggesting that the associations may be mediated by these risk factors.
Conclusions
High-throughput lipidomics may uncover novel sphingolipids predictive of heart disease. Characterization of these lipid species could provide insights into disease etiology.
Funding Sources
This work was supported by the National University Health System and the National Research Foundation Investigatorship grant.
Supporting Tables, Images and/or Graphs
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21
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore; Life Sciences Institute Neurobiology Research Programme, National University of Singapore, Singapore
| | - John Jia En Chua
- Life Sciences Institute Neurobiology Research Programme; Department of Physiology, National University of Singapore; Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore
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22
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Srikanth M, Chew WS, Hind T, Lim SM, Hay NWJ, Lee JHM, Rivera R, Chun J, Ong WY, Herr DR. Lysophosphatidic acid and its receptor LPA1 mediate carrageenan induced inflammatory pain in mice. Eur J Pharmacol 2018; 841:49-56. [DOI: 10.1016/j.ejphar.2018.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 09/28/2018] [Accepted: 10/09/2018] [Indexed: 10/28/2022]
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23
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Srikanth M, Chandrasaharan K, Zhao X, Chayaburakul K, Ong WY, Herr DR. Metabolism of Docosahexaenoic Acid (DHA) Induces Pyroptosis in BV-2 Microglial Cells. Neuromolecular Med 2018; 20:504-514. [PMID: 30232677 DOI: 10.1007/s12017-018-8511-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 09/10/2018] [Indexed: 11/28/2022]
Abstract
DHA is one of the most abundant fatty acids in the brain, largely present in stores of membrane phospholipids. It is readily released by the action of phospholipase A2 and is known to induce anti-inflammatory and neurotrophic effects. It is not thought to contribute to proinflammatory processes in the brain. In this study, an immortalized murine microglia cell line (BV-2) was used to evaluate the effect of DHA on neuroinflammatory cells. Pretreatment of BV-2 cells with low concentrations of DHA (30 µM) attenuates lipopolysaccharide-mediated inflammatory cytokine gene expression, consistent with known anti-inflammatory effects. However, higher (but still physiologically relevant) concentrations of DHA (200 µM) induce profound cell swelling and a reduction of viability. This is accompanied by increases in the expressions of inflammatory cytokine and lipoxygenase genes, activation of caspase-1 activity, and release of IL1β, indicating that cells were undergoing a proinflammatory cell death program known as pyroptosis. This process could be attenuated by pharmacological inhibition of 12-lipoxygenase (12-LOX, Alox12e), but not by inhibition of 5-LOX or 15-LOX. Cumulatively, these data demonstrate that DHA has an anti-inflammatory effect on microglial cells, but its metabolism by 12-LOX generates one or more products that activate a proinflammatory cell death program.
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Affiliation(s)
- Malavika Srikanth
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, Singapore
| | - Kalashobini Chandrasaharan
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, Singapore
| | - Xinyuan Zhao
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, Singapore
| | | | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, Singapore
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, Singapore. .,Department of Biology, San Diego State University, San Diego, CA, USA.
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24
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Tan LHR, Tan AJR, Ng YY, Chua JJE, Chew WS, Muralidharan S, Torta F, Dutta B, Sze SK, Herr DR, Ong WY. Enriched Expression of Neutral Sphingomyelinase 2 in the Striatum is Essential for Regulation of Lipid Raft Content and Motor Coordination. Mol Neurobiol 2018; 55:5741-5756. [PMID: 29043558 PMCID: PMC5994222 DOI: 10.1007/s12035-017-0784-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 09/20/2017] [Indexed: 12/20/2022]
Abstract
Sphingomyelinases are a family of enzymes that hydrolyze sphingomyelin to generate phosphocholine and ceramide. The brain distribution and function of neutral sphingomyelinase 2 (nSMase2) were elucidated in this study. nSMase2 mRNA expression was greatest in the striatum, followed by the prefrontal cortex, hippocampus, cerebellum, thalamus, brainstem, and olfactory bulb. The striatum had the highest level of nSMase2 protein expression, followed by the prefrontal cortex, thalamus, hippocampus, brainstem, and cerebellum. Dense immunolabeling was observed in the striatum, including the caudate-putamen, while moderately dense staining was found in the olfactory bulb and cerebral neocortex. Electron microscopy of the caudate-putamen showed nSMase2 immunoreaction product was present in small diameter dendrites or dendritic spines, that formed asymmetrical synapses with unlabeled axon terminals containing small round vesicles; and characteristics of glutamatergic axons. Lipidomic analysis of the striatum showed increase in long chain sphingomyelins, SM36:1 and SM38:1 after inhibition of nSMase activity. Quantitative proteomic analysis of striatal lipid raft fraction showed many proteins were downregulated by more than 2-fold after inhibition or antisense knockdown of nSMase; consistent with the notion that nSMase2 activity is important for aggregation or clustering of proteins in lipid rafts. Inhibition or antisense knockdown of nSMase2 in the caudate-putamen resulted in motor deficits in the rotarod and narrow beam tests; as well as decreased acoustic startle and improved prepulse inhibition of the startle reflex. Together, results indicate an important function of nSMase2 in the striatum.
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Affiliation(s)
- Laura Hui-Ru Tan
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Angela Jin-Rong Tan
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Yu-Ying Ng
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - John Jia-En Chua
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore
- Department of Physiology, National University of Singapore, Singapore, 119260, Singapore
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, 138673, Singapore
| | - Wee-Siong Chew
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore
| | - Sneha Muralidharan
- Department of Biological Sciences, National University of Singapore, Singapore, 119260, Singapore
| | - Federico Torta
- Department of Biochemistry, National University of Singapore, Singapore, 119260, Singapore
| | - Bamaprasad Dutta
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Siu Kwan Sze
- School of Biological Sciences, Nanyang Technological University, Singapore, 637551, Singapore
| | - Deron R Herr
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore.
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore.
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25
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Ho CFY, Ismail NB, Koh JKZ, Gunaseelan S, Low YH, Ng YK, Chua JJE, Ong WY. Localisation of Formyl-Peptide Receptor 2 in the Rat Central Nervous System and Its Role in Axonal and Dendritic Outgrowth. Neurochem Res 2018; 43:1587-1598. [PMID: 29948727 PMCID: PMC6061218 DOI: 10.1007/s11064-018-2573-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/06/2018] [Accepted: 06/09/2018] [Indexed: 01/03/2023]
Abstract
Arachidonic acid and docosahexaenoic acid (DHA) released by the action of phospholipases A2 (PLA2) on membrane phospholipids may be metabolized by lipoxygenases to the anti-inflammatory mediators lipoxin A4 (LXA4) and resolvin D1 (RvD1), and these can bind to a common receptor, formyl-peptide receptor 2 (FPR2). The contribution of this receptor to axonal or dendritic outgrowth is unknown. The present study was carried out to elucidate the distribution of FPR2 in the rat CNS and its role in outgrowth of neuronal processes. FPR2 mRNA expression was greatest in the brainstem, followed by the spinal cord, thalamus/hypothalamus, cerebral neocortex, hippocampus, cerebellum and striatum. The brainstem and spinal cord also contained high levels of FPR2 protein. The cerebral neocortex was moderately immunolabelled for FPR2, with staining mostly present as puncta in the neuropil. Dentate granule neurons and their axons (mossy fibres) in the hippocampus were very densely labelled. The cerebellar cortex was lightly stained, but the deep cerebellar nuclei, inferior olivary nucleus, vestibular nuclei, spinal trigeminal nucleus and dorsal horn of the spinal cord were densely labelled. Electron microscopy of the prefrontal cortex showed FPR2 immunolabel mostly in immature axon terminals or ‘pre-terminals’, that did not form synapses with dendrites. Treatment of primary hippocampal neurons with the FPR2 inhibitors, PBP10 or WRW4, resulted in reduced lengths of axons and dendrites. The CNS distribution of FPR2 suggests important functions in learning and memory, balance and nociception. This might be due to an effect of FPR2 in mediating arachidonic acid/LXA4 or DHA/RvD1-induced axonal or dendritic outgrowth.
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Affiliation(s)
| | - Nadia Binte Ismail
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Joled Kong-Ze Koh
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Saravanan Gunaseelan
- Department of Physiology, National University of Singapore, Singapore, 119260, Singapore
| | - Yi-Hua Low
- Institute of Neurology, University College London, London, UK
| | - Yee-Kong Ng
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - John Jia-En Chua
- Department of Physiology, National University of Singapore, Singapore, 119260, Singapore. .,Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore, 138673. .,Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 117456, Singapore.
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore. .,Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 117456, Singapore.
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26
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Abstract
The prefrontal cortex (PFC) is not only important in executive functions, but also pain processing. The latter is dependent on its connections to other areas of the cerebral neocortex, hippocampus, periaqueductal gray (PAG), thalamus, amygdala, and basal nuclei. Changes in neurotransmitters, gene expression, glial cells, and neuroinflammation occur in the PFC during acute and chronic pain, that result in alterations to its structure, activity, and connectivity. The medial PFC (mPFC) could serve dual, opposing roles in pain: (1) it mediates antinociceptive effects, due to its connections with other cortical areas, and as the main source of cortical afferents to the PAG for modulation of pain. This is a ‘loop’ where, on one side, a sensory stimulus is transformed into a perceptual signal through high brain processing activity, and perceptual activity is then utilized to control the flow of afferent sensory stimuli at their entrance (dorsal horn) to the CNS. (2) It could induce pain chronification via its corticostriatal projection, possibly depending on the level of dopamine receptor activation (or lack of) in the ventral tegmental area-nucleus accumbens reward pathway. The PFC is involved in biopsychosocial pain management. This includes repetitive transcranial magnetic stimulation, transcranial direct current stimulation, antidepressants, acupuncture, cognitive behavioral therapy, mindfulness, music, exercise, partner support, empathy, meditation, and prayer. Studies demonstrate the role of the PFC during placebo analgesia, and in establishing links between pain and depression, anxiety, and loss of cognition. In particular, losses in PFC grey matter are often reversible after successful treatment of chronic pain.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore.
| | | | - Deron R Herr
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore.
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27
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Farooqui AA, Farooqui T, Madan A, Ong JHJ, Ong WY. Ayurvedic Medicine for the Treatment of Dementia: Mechanistic Aspects. Evid Based Complement Alternat Med 2018; 2018:2481076. [PMID: 29861767 PMCID: PMC5976976 DOI: 10.1155/2018/2481076] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 03/22/2018] [Accepted: 04/02/2018] [Indexed: 12/13/2022]
Abstract
Ayurvedic medicine is a personalized system of traditional medicine native to India and the Indian subcontinent. It is based on a holistic view of treatment which promotes and supports equilibrium in different aspects of human life: the body, mind, and soul. Popular Ayurvedic medicinal plants and formulations that are used to slow down brain aging and enhance memory include Ashwagandha (Withania somnifera), Turmeric (Curcuma longa), Brahmi (Bacopa monnieri), Shankhpushpi (Convolvulus pluricaulis, Evolvulus alsinoides, and other species), gotu kola (Centella asiatica), and guggulu (Commiphora mukul and related species) and a formulation known as Brāhmī Ghṛita, containing Brahmi, Vacā (Acorus calamus), Kuṣṭha (Saussurea lappa), Shankhpushpi, and Purāṇa Ghṛita (old clarified butter/old ghee). The rationale for the utilization of Ayurvedic medicinal plants has depended mostly on traditional usage, with little scientific data on signal transduction processes, efficacy, and safety. However, in recent years, pharmacological and toxicological studies have begun to be published and receive attention from scientists for verification of their claimed pharmacological and therapeutic effects. The purpose of this review is to outline the molecular mechanisms, signal transduction processes, and sites of action of some Ayurvedic medicinal plants. It is hoped that this description can be further explored with modern scientific methods, to reveal new therapeutic leads and jump-start more studies on the use of Ayurvedic medicine for prevention and treatment of dementia.
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Affiliation(s)
- Akhlaq A. Farooqui
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH 43221, USA
| | - Tahira Farooqui
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH 43221, USA
| | - Anil Madan
- Department of Pathology, Rajshree Medical Research Institute Bareilly, Bareilly, India
| | | | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore 119260
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28
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Chong JR, Xiang P, Wang W, Hind T, Chew WS, Ong WY, Lai MKP, Herr DR. Sphingolipidomics analysis of large clinical cohorts. Part 2: Potential impact and applications. Biochem Biophys Res Commun 2018; 504:602-607. [PMID: 29654757 DOI: 10.1016/j.bbrc.2018.04.075] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 04/10/2018] [Indexed: 11/18/2022]
Abstract
It has been known for decades that the regulation of sphingolipids (SLs) is essential for the proper function of many cellular processes. However, a complete understanding of these processes has been complicated by the structural diversity of these lipids. A well-characterized metabolic pathway is responsible for homeostatic maintenance of hundreds of distinct SL species. This pathway is perturbed in a number of pathological processes, resulting in derangement of the "sphingolipidome." Recently, advances in mass spectrometry (MS) techniques have made it possible to characterize the sphingolipidome in large-scale clinical studies, allowing for the identification of specific SL molecules that mediate pathological processes and/or may serve as biomarkers. This manuscript provides an overview of the functions of SLs, and reviews previous studies that have used MS techniques to identify changes to the sphingolipidome in non-metabolic diseases.
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Affiliation(s)
- Joyce R Chong
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore
| | - Ping Xiang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore
| | - Wei Wang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore
| | - Tatsuma Hind
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore; Department of Pharmacology, University of British Columbia, Vancouver, BC, Canada
| | - Wee Siong Chew
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, 119260, Singapore; Neurobiology and Ageing Research Programme, Life Sciences Institute, National University of Singapore, 119260, Singapore
| | - Mitchell K P Lai
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore; Neurobiology and Ageing Research Programme, Life Sciences Institute, National University of Singapore, 119260, Singapore
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, 117597, Singapore; Department of Biology, San Diego State University, San Diego, CA, USA.
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Herr DR, Ong JHJ, Ong WY. Potential Therapeutic Applications for Inhibitors of Autotaxin, a Bioactive Lipid-Producing Lysophospholipase D, in Disorders Affecting the Nervous System. ACS Chem Neurosci 2018; 9:398-400. [PMID: 29457888 DOI: 10.1021/acschemneuro.8b00057] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Autotaxin is a dual-function ecto-enzyme, encoded by the gene ENPP2, which is the primary source of the bioactive signaling lipid, lysophosphatidic acid. Aberrations in autotaxin/lysophosphatidic acid signaling have been associated with a number of neurological, psychiatric, neoplastic, and neurodevelopmental conditions, such as pain, pruritus, glioblastoma multiforme, multiple sclerosis, Alzheimer's disease, hydrocephalus, and schizophrenia. This Viewpoint offers a brief overview of the likely indications for therapeutic targeting of autotaxin, in disorders affecting the nervous system.
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Affiliation(s)
- Deron R. Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600
- Department of Biology, San Diego State University, San Diego, California 92182, United States
| | - Jolin Hwee-Jing Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260
- Neurobiology and Ageing Research Programme, Life Sciences Institute, National University of Singapore, Singapore 119260
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30
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Abstract
The Traditional Chinese Medicine (TCM) theory that “kidneys give rise to marrow, and the brain is the sea of marrow” has been a guide for the clinical application of kidney, qi and blood tonics for prevention and treatment of dementia and improvement in memory. As low resistance end-organs, both the brain and the kidneys are subjected to blood flow of high volumes throughout the cardiac cycle. Alzheimer’s disease and vascular dementia are two common causes of dementia, and it is increasingly recognized that many older adults with dementia have both AD and vascular pathologies. The underlying molecular mechanisms are incompletely understood, but may involve atherosclerosis, vascular dysfunction, hypertension, type 2 diabetes, history of cardiac disease and possibly, kidney dysfuntion, leading to reduced erythropoietin production, anemia, brain energy deficit and slow excitotoxicity. During the Ming Dynasty, Zhang Jing-Yue used Qi Fu Yin (seven blessings decoction), comprising Panax ginseng, Rehmannia glutinosa, Angelica polymorpha, Atractylodes macrocephala, Glycyrrhiza uralensis, Ziziphus jujube, and Polygala tenuifolia to boost qi and blood circulation, strengthen the heart, and calm the spirit—skillfully linking heart, spleen, kidney, qi, blood and brain as a whole to treat age-related dementia. The purpose of this review is to outline TCM concepts for the treatment of dementia and illustrated with a historical prescription for the treatment of the condition, with the hope that this description may lead to advances in its management.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore. .,Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore.
| | - Ya-Jun Wu
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Tahira Farooqui
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH, 43220, USA
| | - Akhlaq A Farooqui
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH, 43220, USA
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Shalini SM, Ho CFY, Ng YK, Tong JX, Ong ES, Herr DR, Dawe GS, Ong WY. Distribution of Alox15 in the Rat Brain and Its Role in Prefrontal Cortical Resolvin D1 Formation and Spatial Working Memory. Mol Neurobiol 2018; 55:1537-1550. [PMID: 28181190 PMCID: PMC5820376 DOI: 10.1007/s12035-017-0413-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 01/18/2017] [Indexed: 10/28/2022]
Abstract
Docosahexaenoic acid (DHA) is enriched in membrane phospholipids of the central nervous system (CNS) and has a role in aging and neuropsychiatric disorders. DHA is metabolized by the enzyme Alox15 to 17S-hydroxy-DHA, which is then converted to 7S-hydroperoxy,17S-hydroxy-DHA by a 5-lipoxygenase, and thence via epoxy intermediates to the anti-inflammatory molecule, resolvin D1 (RvD1 or 7S,8R,17S-trihydroxy-docosa-Z,9E,11E,13Z,15E,19Z-hexaenoic acid). In this study, we investigated the distribution and function of Alox15 in the CNS. RT-PCR of the CNS showed that the prefrontal cortex exhibits the highest Alox15 mRNA expression level, followed by the parietal association cortex and secondary auditory cortex, olfactory bulb, motor and somatosensory cortices, and the hippocampus. Western blot analysis was consistent with RT-PCR data, in that the prefrontal cortex, cerebral cortex, hippocampus, and olfactory bulb had high Alox15 protein expression. Immunohistochemistry showed moderate staining in the olfactory bulb, cerebral cortex, septum, striatum, cerebellar cortex, cochlear nuclei, spinal trigeminal nucleus, and dorsal horn of the spinal cord. Immuno-electron microscopy showed localization of Alox15 in dendrites, in the prefrontal cortex. Liquid chromatography mass spectrometry analysis showed significant decrease in resolvin D1 levels in the prefrontal cortex after inhibition or antisense knockdown of Alox15. Alox15 inhibition or antisense knockdown in the prefrontal cortex also blocked long-term potentiation of the hippocampo-prefrontal cortex pathway and increased errors in alternation, in the T-maze test. They indicate that Alox15 processing of DHA contributes to production of resolvin D1 and LTP at hippocampo-prefrontal cortical synapses and associated spatial working memory performance. Together, results provide evidence for a key role of anti-inflammatory molecules generated by Alox15 and DHA, such as resolvin D1, in memory. They suggest that neuroinflammatory brain disorders and chronic neurodegeneration may 'drain' anti-inflammatory molecules that are necessary for normal neuronal signaling, and compromise cognition.
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Affiliation(s)
- Suku-Maran Shalini
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore
| | - Christabel Fung-Yih Ho
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore
| | - Yee-Kong Ng
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Jie-Xin Tong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Eng-Shi Ong
- Department of Science, Singapore University of Technology and Design, Singapore, 487372, Singapore
| | - Deron R Herr
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore
| | - Gavin S Dawe
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore.
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32
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Ho CFY, Bon CPE, Ng YK, Herr DR, Wu JS, Lin TN, Ong WY. Expression of DHA-Metabolizing Enzyme Alox15 is Regulated by Selective Histone Acetylation in Neuroblastoma Cells. Neurochem Res 2017; 43:540-555. [PMID: 29235036 PMCID: PMC5842265 DOI: 10.1007/s11064-017-2448-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 11/28/2017] [Accepted: 12/03/2017] [Indexed: 12/31/2022]
Abstract
The omega-3 polyunsaturated fatty acid, docosahexaenoic acid (DHA) is enriched in neural membranes of the CNS, and recent studies have shown a role of DHA metabolism by 15-lipoxygenase-1 (Alox15) in prefrontal cortex resolvin D1 formation, hippocampo-prefrontal cortical long-term-potentiation, spatial working memory, and anti-nociception/anxiety. In this study, we elucidated epigenetic regulation of Alox15 via histone modifications in neuron-like cells. Treatment of undifferentiated SH-SY5Y human neuroblastoma cells with the histone deacetylase (HDAC) inhibitors trichostatin A (TSA) and sodium butyrate significantly increased Alox15 mRNA expression. Moreover, Alox15 expression was markedly upregulated by Class I HDAC inhibitors, MS-275 and depsipeptide. Co-treatment of undifferentiated SH-SY5Y cells with the p300 histone acetyltransferase (HAT) inhibitor C646 and TSA or sodium butyrate showed that p300 HAT inhibition modulated TSA or sodium butyrate-induced Alox15 upregulation. Differentiation of SH-SY5Y cells with retinoic acid resulted in increased neurite outgrowth and Alox15 mRNA expression, while co-treatment with the p300 HAT inhibitor C646 and retinoic acid modulated the increases, indicating a role of p300 HAT in differentiation-associated Alox15 upregulation. Increasing Alox15 expression was found in primary murine cortical neurons during development from 3 to 10 days-in-vitro, reaching high levels of expression by 10 days-in-vitro—when Alox15 was not further upregulated by HDAC inhibition. Together, results indicate regulation of Alox15 mRNA expression in neuroblastoma cells by histone modifications, and increasing Alox15 expression in differentiating neurons. It is possible that one of the environmental influences on the immature brain that can affect cognition and memory, may take the form of epigenetic effects on Alox15 and metabolites of DHA.
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Affiliation(s)
| | - Claire Poh-Ee Bon
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Yee-Kong Ng
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Deron R Herr
- Department of Pharmacology, National University of Singapore, Singapore, 119260, Singapore
| | - Jui-Sheng Wu
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan
| | - Teng-Nan Lin
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.,Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore. .,Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 117456, Singapore.
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Wu JS, Kao MH, Tsai HD, Cheung WM, Chen JJ, Ong WY, Sun GY, Lin TN. Clinacanthus nutans Mitigates Neuronal Apoptosis and Ischemic Brain Damage Through Augmenting the C/EBPβ-Driven PPAR-γ Transcription. Mol Neurobiol 2017; 55:5425-5438. [PMID: 28942553 DOI: 10.1007/s12035-017-0776-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 09/15/2017] [Indexed: 02/07/2023]
Abstract
Clinacanthus nutans Lindau (C. nutans) is a traditional herbal medicine widely used in Asian countries for treating a number of remedies including snake and insect bites, skin rashes, viral infections, and cancer. However, the underlying molecular mechanisms for its action and whether C. nutans can offer protection on stroke damage in brain remain largely unknown. In the present study, we demonstrated protective effects of C. nutans extract to ameliorate neuronal apoptotic death in the oxygen-glucose deprivation model and to reduce infarction and mitigate functional deficits in the middle cerebral artery occlusion model, either administered before or after hypoxic/ischemic insult. Using pharmacological antagonist and siRNA knockdown approaches, we demonstrated ability for C. nutans extract to protect neurons and ameliorate ischemic injury through promoting the anti-apoptotic activity of peroxisome proliferator-activated receptor-gamma (PPAR-γ), a stress-induced transcription factor. Reporter and chromatin immunoprecipitation promoter analysis further revealed C. nutans extract to selectively increase CCAAT/enhancer binding protein (C/EBP)β binding to specific C/EBP binding site (-332~-325) on the PPAR-γ promoter to augment its transcription. In summary, we report a novel transcriptional activation involving C/EBPβ upregulation of PPAR-γ expression to suppress ischemic neuronal apoptosis and brain infarct. Recognition of C. nutans to enhance the C/EBPβ → PPAR-γ neuroprotective signaling pathway paves a new way for future drug development for prevention and treatment of ischemic stroke and other neurodegenerative diseases.
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Affiliation(s)
- Jui-Sheng Wu
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, Republic of China
| | - Mei-Han Kao
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, Republic of China
| | - Hsin-Da Tsai
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, Republic of China
| | - Wai-Mui Cheung
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, Republic of China
| | - Jin-Jer Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, Republic of China
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, Singapore
| | - Grace Y Sun
- Department of Biochemistry, University of Missouri, Columbia, MO, USA
| | - Teng-Nan Lin
- Institute of Biomedical Sciences, Academia Sinica, Taipei, 11529, Taiwan, Republic of China. .,Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Republic of China.
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34
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Li ZY, Chung YH, Shin EJ, Dang DK, Jeong JH, Ko SK, Nah SY, Baik TG, Jhoo JH, Ong WY, Nabeshima T, Kim HC. YY-1224, a terpene trilactone-strengthened Ginkgo biloba, attenuates neurodegenerative changes induced by β-amyloid (1-42) or double transgenic overexpression of APP and PS1 via inhibition of cyclooxygenase-2. J Neuroinflammation 2017; 14:94. [PMID: 28449688 PMCID: PMC5408406 DOI: 10.1186/s12974-017-0866-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 04/18/2017] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Ginkgo biloba has been reported to possess free radical-scavenging antioxidant activity and anti-inflammatory properties. In our pilot study, YY-1224, a terpene trilactone-strengthened extract of G. biloba, showed anti-inflammatory, neurotrophic, and antioxidant effects. RESULTS We investigated the pharmacological potential of YY-1224 in β-amyloid (Aβ) (1-42)-induced memory impairment using cyclooxygenase-2 (COX-2) knockout (-/-) and APPswe/PS1dE9 transgenic (APP/PS1 Tg) mice. Repeated treatment with YY-1224 significantly attenuated Aβ (1-42)-induced memory impairment in COX-2 (+/+) mice, but not in COX-2 (-/-) mice. YY-1224 significantly attenuated Aβ (1-42)-induced upregulation of platelet-activating factor (PAF) receptor gene expression, reactive oxygen species, and pro-inflammatory factors. In addition, YY-1224 significantly inhibited Aβ (1-42)-induced downregulation of PAF-acetylhydrolase-1 (PAF-AH-1) and peroxisome proliferator-activated receptor γ (PPARγ) gene expression. These changes were more pronounced in COX-2 (+/+) mice than in COX-2 (-/-) mice. YY-1224 significantly attenuated learning impairment, Aβ deposition, and pro-inflammatory microglial activation in APP/PS1 Tg mice, whereas it significantly enhanced PAF-AH and PPARγ expression. A preferential COX-2 inhibitor, meloxicam, did not affect the pharmacological activity by YY-1224, suggesting that the COX-2 gene is a critical mediator of the neuroprotective effects of YY-1224. The protective activity of YY-1224 appeared to be more efficacious than a standard G. biloba extract (Gb) against Aβ insult. CONCLUSIONS Our results suggest that the protective effects of YY-1224 against Aβ toxicity may be associated with its PAF antagonistic- and PPARγ agonistic-potential as well as inhibition of the Aβ-mediated pro-inflammatory switch of microglia phenotypes through suppression of COX-2 expression.
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Affiliation(s)
- Zheng-Yi Li
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon, 24341 Republic of Korea
| | - Yoon Hee Chung
- Department of Anatomy, College of Medicine, Chung-Ang University, Seoul, 06974 Republic of Korea
| | - Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon, 24341 Republic of Korea
| | - Duy-Khanh Dang
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon, 24341 Republic of Korea
| | - Ji Hoon Jeong
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul, 06974 Republic of Korea
| | - Sung Kwon Ko
- Department of Oriental Medical Food and Nutrition, Semyung University, Jecheon, 27136 Republic of Korea
| | - Seung-Yeol Nah
- Ginsentology Research Laboratory and Department of Physiology, College of Veterinary Medicine and Bio/Molecular Informatics Center, Konkuk University, Seoul, 05029 Republic of Korea
| | - Tae Gon Baik
- R&D Center, Yuyu Pharma, Seoul, 04598 Republic of Korea
| | - Jin Hyeong Jhoo
- Department of Psychiatry, Medical School, Kangwon National University, Chunchon, 24341 Republic of Korea
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260 Singapore
| | - Toshitaka Nabeshima
- Nabeshima Laboratory, Graduate School of Pharmaceutical Sciences, Meijo University, Nagoya, 468-8503 Japan
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon, 24341 Republic of Korea
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35
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Chen Y, Bang S, McMullen MF, Kazi H, Talbot K, Ho MX, Carlson G, Arnold SE, Ong WY, Kim SF. Neuronal Activity-Induced Sterol Regulatory Element Binding Protein-1 (SREBP1) is Disrupted in Dysbindin-Null Mice-Potential Link to Cognitive Impairment in Schizophrenia. Mol Neurobiol 2017; 54:1699-1709. [PMID: 26873854 PMCID: PMC4982840 DOI: 10.1007/s12035-016-9773-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 02/02/2016] [Indexed: 12/30/2022]
Abstract
Schizophrenia is a chronic debilitating neuropsychiatric disorder that affects about 1 % of the population. Dystrobrevin-binding protein 1 (DTNBP1 or dysbindin) is one of the Research Domain Constructs (RDoC) associated with cognition and is significantly reduced in the brain of schizophrenia patients. To further understand the molecular underpinnings of pathogenesis of schizophrenia, we have performed microarray analyses of the hippocampi from dysbindin knockout mice, and found that genes involved in the lipogenic pathway are suppressed. Moreover, we discovered that maturation of a master transcriptional regulator for lipid synthesis, sterol regulatory element binding protein-1 (SREBP1) is induced by neuronal activity, and is required for induction of the immediate early gene ARC (activity-regulated cytoskeleton-associated protein), necessary for synaptic plasticity and memory. We found that nuclear SREBP1 is dramatically reduced in dysbindin-1 knockout mice and postmortem brain tissues from human patients with schizophrenia. Furthermore, activity-dependent maturation of SREBP1 as well as ARC expression were attenuated in dysbindin-1 knockout mice, and these deficits were restored by an atypical antipsychotic drug, clozapine. Together, results indicate an important role of dysbindin-1 in neuronal activity induced SREBP1 and ARC, which could be related to cognitive deficits in schizophrenia.
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Affiliation(s)
- Yong Chen
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Sookhee Bang
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Mary F McMullen
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Hala Kazi
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Konrad Talbot
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Mei-Xuan Ho
- Department of Anatomy and Neurobiology Research Programme, National University of Singapore, Singapore, 119260, Singapore
| | - Greg Carlson
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Steven E Arnold
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Wei-Yi Ong
- Department of Anatomy and Neurobiology Research Programme, National University of Singapore, Singapore, 119260, Singapore.
| | - Sangwon F Kim
- Department of Psychiatry, Center for Neurobiology and Behavior, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA.
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, 19104, USA.
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Loke SY, Wong PTH, Ong WY. Global gene expression changes in the prefrontal cortex of rabbits with hypercholesterolemia and/or hypertension. Neurochem Int 2016; 102:33-56. [PMID: 27890723 DOI: 10.1016/j.neuint.2016.11.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 11/14/2016] [Accepted: 11/23/2016] [Indexed: 02/01/2023]
Abstract
Although many studies have identified a link between hypercholesterolemia or hypertension and cognitive deficits, till date, comprehensive gene expression analyses of the brain under these conditions is still lacking. The present study was carried out to elucidate differential gene expression changes in the prefrontal cortex (PFC) of New Zealand white rabbits exposed to hypercholesterolemia and/or hypertension with a view of identifying gene networks at risk. Microarray analyses of the PFC of hypercholesterolemic rabbits showed 850 differentially expressed genes (DEGs) in the cortex of hypercholesterolemic rabbits compared to controls, but only 5 DEGs in hypertensive rabbits compared to controls. Up-regulated genes in the PFC of hypercholesterolemic rabbits included CIDEC, ODF2, RNASEL, FSHR, CES3 and MAB21L3, and down-regulated genes included FAM184B, CUL3, LOC100351029, TMEM109, LOC100357097 and PFDN5. Comparison with our previous study on the middle cerebral artery (MCA) of the same rabbits showed many differentially expressed genes in common between the PFC and MCA, during hypercholesterolemia. Moreover, these genes tended to fall into the same functional networks, as revealed by IPA analyses, with many identical node molecules. These include: proteasome, insulin, Akt, ERK1/2, histone, IL12, interferon alpha and NFκB. Of these, PSMB4, PSMD4, PSMG1 were chosen as representatives of genes related to the proteasome for verification by quantitative RT-PCR. Results indicate significant downregulation of all three proteasome associated genes in the PFC. Immunostaining showed significantly increased number of Aβ labelled cells in layers III and V of the cortex after hypercholesterolemia and hypertension, which may be due to decreased proteasome activity and/or increased β- or γ-secretase activity. Knowledge of altered gene networks during hypercholesterolemia and/or hypertension could inform our understanding of the link between these conditions and cognitive deficits in vascular dementia or Alzheimer's disease.
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Affiliation(s)
- Sau-Yeen Loke
- Department of Anatomy, National University of Singapore, 119260, Singapore
| | - Peter Tsun-Hon Wong
- Department of Pharmacology, National University of Singapore, 119260, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, 119260, Singapore; Neurobiology and Ageing Research Program, Life Sciences Institute, National University of Singapore, 119260, Singapore.
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Too IHK, Yeo H, Sessions OM, Yan B, Libau EA, Howe JLC, Lim ZQ, Suku-Maran S, Ong WY, Chua KB, Wong BS, Chow VTK, Alonso S. Enterovirus 71 infection of motor neuron-like NSC-34 cells undergoes a non-lytic exit pathway. Sci Rep 2016; 6:36983. [PMID: 27849036 PMCID: PMC5111112 DOI: 10.1038/srep36983] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 10/20/2016] [Indexed: 01/08/2023] Open
Abstract
Enterovirus 71 (EV71) causing Hand, Foot and Mouth Disease, is regarded as the most important neurotropic virus worldwide. EV71 is believed to replicate in muscles and infect motor neurons to reach the central nervous system (CNS). To further investigate the mechanisms involved, we have employed the motor neuron cell line NSC-34. NSC-34 cells were permissive to EV71 and virus production yields were strain-dependent with differential efficacy at the entry, replication and egress steps. Furthermore, unlike all the other cell lines previously reported, EV71-infected NSC-34 cells neither displayed cytopathic effect nor underwent apoptosis. Instead, autophagy was markedly up-regulated and virus-containing autophagic vacuoles were isolated from the culture supernatant, providing the first experimental evidence that EV71 can adopt a non-lytic exit pathway. Finally, the ability of EV71 to infect productively NSC-34 cells correlated with its ability to invade the CNS in vivo, supporting the relevance of NSC-34 cells to study the intrinsic neurovirulence of EV71 strains.
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Affiliation(s)
- Issac Horng Khit Too
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Huimin Yeo
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - October Michael Sessions
- Program in Emerging Infectious Diseases, Duke-NUS Graduate Medical School, 8 College Road, 169857, Singapore
| | - Benedict Yan
- Department of Laboratory Medicine, 5 Lower Kent Ridge Road, National University Hospital, 119074, Singapore
| | - Eshele Anak Libau
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Josephine L C Howe
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore
| | - Ze Qin Lim
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Shalini Suku-Maran
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Neurobiology and Ageing Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Kaw Bing Chua
- Temasek Life Sciences Laboratory, 5 A Engineering Drive 1, National University of Singapore, 117411, Singapore
| | - Boon Seng Wong
- Neurobiology and Ageing Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore.,Department of Physiology, Yong Loo Lin School of Medicine, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
| | - Vincent T K Chow
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore
| | - Sylvie Alonso
- Department of Microbiology &Immunology, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore.,Immunology Programme, Life Sciences Institute, CeLS building, 28 Medical Drive, National University of Singapore, 117456, Singapore
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38
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Chew WS, Shalini SM, Torta F, Wenk MR, Stohler C, Yeo JF, Herr DR, Ong WY. Role of prefrontal cortical calcium-independent phospholipase A 2 in antinociceptive effect of the norepinephrine reuptake inhibitor antidepresssant maprotiline. Neuroscience 2016; 340:91-100. [PMID: 27789386 DOI: 10.1016/j.neuroscience.2016.10.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 10/12/2016] [Accepted: 10/14/2016] [Indexed: 12/21/2022]
Abstract
The prefrontal cortex is essential for executive functions such as decision-making and planning. There is also accumulating evidence that it is important for the modulation of pain. In this study, we investigated a possible role of prefrontal cortical calcium-independent phospholipase A2 (iPLA2) in antinociception induced by the norepinephrine reuptake inhibitor (NRI) and tetracyclic (tricyclic) antidepressant, maprotiline. Intraperitoneal injections of maprotiline increased iPLA2 mRNA and protein expression in the prefrontal cortex. This treatment also reduced grooming responses to von-Frey hair stimulation of the face after facial carrageenan injection, indicating decreased sensitivity to pain. The antinociceptive effect of maprotiline was abrogated by iPLA2 antisense oligonucleotide injection to the prefrontal cortex, indicating a role of this enzyme in antinociception. In contrast, injection of iPLA2 antisense oligonucleotide to the somatosensory cortex did not reduce the antinociceptive effect of maprotiline. Lipidomic analysis of the prefrontal cortex showed decrease in phosphatidylcholine species, but increase in lysophosphatidylcholine species, indicating increased PLA2 activity, and release of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) after maprotiline treatment. Differences in sphingomyelin/ceramide were also detected. These changes were not observed in maprotiline-treated mice that received iPLA2 antisense oligonucleotide to the prefrontal cortex. Metabolites of DHA and EPA may help to strengthen a known supraspinal antinociceptive pathway from the prefrontal cortex to the periaqueductal gray. Together, results indicate a role of prefrontal cortical iPLA2 and its enzymatic products in the antinociceptive effect of maprotiline.
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Affiliation(s)
- Wee-Siong Chew
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore
| | - Suku-Maran Shalini
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore; Neurobiology and Ageing Research Programme, National University of Singapore, Singapore 119260, Singapore
| | - Federico Torta
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore 119260, Singapore; Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore
| | - Markus R Wenk
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore 119260, Singapore; Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore; Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore 119260, Singapore
| | | | - Jin-Fei Yeo
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, National University of Singapore, Singapore 119260, Singapore
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119260, Singapore; Neurobiology and Ageing Research Programme, National University of Singapore, Singapore 119260, Singapore.
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Shalini SM, Herr DR, Ong WY. The Analgesic and Anxiolytic Effect of Souvenaid, a Novel Nutraceutical, Is Mediated by Alox15 Activity in the Prefrontal Cortex. Mol Neurobiol 2016; 54:6032-6045. [PMID: 27696115 DOI: 10.1007/s12035-016-0138-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 09/16/2016] [Indexed: 11/25/2022]
Abstract
Pain and anxiety have a complex relationship and pain is known to share neurobiological pathways and neurotransmitters with anxiety. Top-down modulatory pathways of pain have been shown to originate from cortical and subcortical regions, including the dorsolateral prefrontal cortex. In this study, a novel docosahexaenoic acid (DHA)-containing nutraceutical, Souvenaid, was administered to mice with infraorbital nerve ligation-induced neuropathic pain and behavioral responses recorded. Infraorbital nerve ligation resulted in increased face wash strokes of the face upon von Frey hair stimulation, indicating increased nociception. Part of this response involves general pain sensitization that is dependent on the CNS, since increased nociception was also found in the paws during the hot plate test. Mice receiving oral gavage of Souvenaid, a nutraceutical containing DHA; choline; and other cell membrane components, showed significantly reduced pain sensitization. The mechanism of Souvenaid's activity involves supraspinal antinociception, originating in the prefrontal cortex, since inhibition of the DHA-metabolizing enzyme 15-lipoxygenase (Alox15) in the prefrontal cortex attenuated the antinociceptive effect of Souvenaid. Alox15 inhibition also modulated anxiety behavior associated with pain after infraorbital nerve ligation. The effects of Souvenaid components and Alox15 on reducing central sensitization of pain may be due to strengthening of a known supraspinal antinociceptive pathway from the prefrontal cortex to the periaqueductal gray. Together, results indicate the importance of the prefrontal cortex and DHA/Alox15 in central antinociceptive pathways and suggest that Souvenaid may be a novel therapeutic for neuropathic pain.
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Affiliation(s)
- Suku-Maran Shalini
- Department of Anatomy, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, 119260, Singapore
- Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore, Singapore
| | - Deron R Herr
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, Singapore, 119260, Singapore.
- Neurobiology and Ageing Programme, Life Sciences Institute, National University of Singapore, Singapore, Singapore.
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40
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Tan JWS, Ho CFY, Ng YK, Ong WY. Docosahexaenoic acid and L-Carnitine prevent ATP loss in SH-SY5Y neuroblastoma cells after exposure to silver nanoparticles. Environ Toxicol 2016; 31:224-232. [PMID: 25146533 DOI: 10.1002/tox.22037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 07/29/2014] [Accepted: 08/03/2014] [Indexed: 06/03/2023]
Abstract
Silver nanoparticles (AgNPs) are among the most commonly used nanomaterials, but thus far, little is known about ways to mitigate against potential toxic effects of exposure. In this study, we examined the potential effects of AgNPs on mitochondrial function and cellular ATP levels, and whether these could be prevented by treatment with docosahexaenoic acid (DHA) and L-carnitine (LC). Acute exposure of AgNPs for 1 h to SH-SY5Y cells resulted in decreased mitochondrial membrane potential, and decreased ATP and ADP levels, indicating mitochondrial damage and reduced production of ATP. Incubation of cells with DHA partially reduced, while treatment with LC and DHA completely abolished the AgNP induced decreases in ATP and ADP levels. This could be due to a LC-facilitated entry of DHA to mitochondria, for repair of damaged phospholipids. It is postulated that DHA and LC may be useful for treatment of accidental environmental exposure to AgNPs.
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Affiliation(s)
- Joey Wee-Shan Tan
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | | | - Yee-Kong Ng
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
- Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore
- NUS Environmental Research Institute, National University of Singapore, Singapore, 119260, Singapore
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Goh VJ, Tan JSY, Tan BC, Seow C, Ong WY, Lim YC, Sun L, Ghosh S, Silver DL. Postnatal Deletion of Fat Storage-inducing Transmembrane Protein 2 (FIT2/FITM2) Causes Lethal Enteropathy. J Biol Chem 2015; 290:25686-99. [PMID: 26304121 DOI: 10.1074/jbc.m115.676700] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Indexed: 02/03/2023] Open
Abstract
Lipid droplets (LDs) are phylogenetically conserved cytoplasmic organelles that store neutral lipids within a phospholipid monolayer. LDs compartmentalize lipids and may help to prevent cellular damage caused by their excess or bioactive forms. FIT2 is a ubiquitously expressed transmembrane endoplasmic reticulum (ER) membrane protein that has previously been implicated in LD formation in mammalian cells and tissue. Recent data indicate that FIT2 plays an essential role in fat storage in an in vivo constitutive adipose FIT2 knock-out mouse model, but the physiological effects of postnatal whole body FIT2 depletion have never been studied. Here, we show that tamoxifen-induced FIT2 deletion using a whole body ROSA26CreER(T2)-driven FIT2 knock-out (iF2KO) mouse model leads to lethal intestinal pathology, including villus blunting and death of intestinal crypts, and loss of lipid absorption. iF2KO mice lose weight and die within 2 weeks after the first tamoxifen dose. At the cellular level, LDs failed to form in iF2KO enterocytes after acute oil challenge and instead accumulated within the ER. Intestinal bile acid transporters were transcriptionally dysregulated in iF2KO mice, leading to the buildup of bile acids within enterocytes. These data support the conclusion that FIT2 plays an essential role in regulating intestinal health and survival postnatally.
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Affiliation(s)
- Vera J Goh
- From the Signature Research Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore Graduate Medical School, 8 College Road, 169857 Singapore and
| | - Jolene S Y Tan
- From the Signature Research Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore Graduate Medical School, 8 College Road, 169857 Singapore and
| | - Bryan C Tan
- From the Signature Research Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore Graduate Medical School, 8 College Road, 169857 Singapore and
| | - Colin Seow
- From the Signature Research Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore Graduate Medical School, 8 College Road, 169857 Singapore and
| | - Wei-Yi Ong
- the Department of Anatomy and Neurobiology and Aging Research Programme, National University of Singapore, Singapore 119260, Singapore
| | - Yen Ching Lim
- From the Signature Research Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore Graduate Medical School, 8 College Road, 169857 Singapore and
| | - Lei Sun
- From the Signature Research Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore Graduate Medical School, 8 College Road, 169857 Singapore and
| | - Sujoy Ghosh
- From the Signature Research Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore Graduate Medical School, 8 College Road, 169857 Singapore and
| | - David L Silver
- From the Signature Research Program in Cardiovascular and Metabolic Disorders, Duke-National University of Singapore Graduate Medical School, 8 College Road, 169857 Singapore and
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43
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Ong WY, Farooqui T, Koh HL, Farooqui AA, Ling EA. Protective effects of ginseng on neurological disorders. Front Aging Neurosci 2015; 7:129. [PMID: 26236231 PMCID: PMC4503934 DOI: 10.3389/fnagi.2015.00129] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 06/23/2015] [Indexed: 12/20/2022] Open
Abstract
Ginseng (Order: Apiales, Family: Araliaceae, Genus: Panax) has been used as a traditional herbal medicine for over 2000 years, and is recorded to have antianxiety, antidepressant and cognition enhancing properties. The protective effects of ginseng on neurological disorders are discussed in this review. Ginseng species and ginsenosides, and their intestinal metabolism and bioavailability are briefly introduced. This is followed by molecular mechanisms of effects of ginseng on the brain, including glutamatergic transmission, monoamine transmission, estrogen signaling, nitric oxide (NO) production, the Keap1/Nrf2 adaptive cellular stress pathway, neuronal survival, apoptosis, neural stem cells and neuroregeneration, microglia, astrocytes, oligodendrocytes and cerebral microvessels. The molecular mechanisms of the neuroprotective effects of ginseng in Alzheimer’s disease (AD) including β-amyloid (Aβ) formation, tau hyperphosphorylation and oxidative stress, major depression, stroke, Parkinson’s disease and multiple sclerosis are presented. It is hoped that this discussion will stimulate more studies on the use of ginseng in neurological disorders.
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Affiliation(s)
- Wei-Yi Ong
- Department of Anatomy, National University of Singapore Singapore, Singapore ; Neurobiology and Ageing Research Programme, National University of Singapore Singapore, Singapore
| | - Tahira Farooqui
- Department of Molecular and Cellular Biochemistry, The Ohio State University Columbus, OH, USA
| | - Hwee-Ling Koh
- Department of Pharmacy, National University of Singapore Singapore, Singapore
| | - Akhlaq A Farooqui
- Department of Molecular and Cellular Biochemistry, The Ohio State University Columbus, OH, USA
| | - Eng-Ang Ling
- Department of Anatomy, National University of Singapore Singapore, Singapore
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Tan CSH, Ng YK, Ong WY. Epigenetic Regulation of Cytosolic Phospholipase A2 in SH-SY5Y Human Neuroblastoma Cells. Mol Neurobiol 2015; 53:3854-3872. [PMID: 26162318 DOI: 10.1007/s12035-015-9314-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 06/23/2015] [Indexed: 12/19/2022]
Abstract
Group IVA cytosolic phospholipase A2 (cPLA2 or PLA2G4A) is a key enzyme that contributes to inflammation via the generation of arachidonic acid and eicosanoids. While much is known about regulation of cPLA2 by posttranslational modification such as phosphorylation, little is known about its epigenetic regulation. In this study, treatment with histone deacetylase (HDAC) inhibitors, trichostatin A (TSA), valproic acid, tubacin and the class I HDAC inhibitor, MS-275, were found to increase cPLA2α messenger RNA (mRNA) expression in SH-SY5Y human neuroblastoma cells. Co-treatment of the histone acetyltransferase (HAT) inhibitor, anacardic acid, modulated upregulation of cPLA2α induced by TSA. Specific involvement of class I HDACs and HAT in cPLA2α regulation was further shown, and a Tip60-specific HAT inhibitor, NU9056, modulated the upregulation of cPLA2α induced by MS-275. In addition, co-treatment of with histone methyltransferase (HMT) inhibitor, 5'-deoxy-5'-methylthioadenosine (MTA) suppressed TSA-induced cPLA2α upregulation. The above changes in cPLA2 mRNA expression were reflected at the protein level by Western blots and immunocytochemistry. Chromatin immunoprecipitation (ChIP) showed TSA increased binding of trimethylated H3K4 to the proximal promoter region of the cPLA2α gene. Cell injury after TSA treatment as indicated by lactate dehydrogenase (LDH) release was modulated by anacardic acid, and a role of cPLA2 in mediating TSA-induced injury shown, after co-incubation with the cPLA2 selective inhibitor, arachidonoyl trifluoromethyl ketone (AACOCF3). Together, results indicate epigenetic regulation of cPLA2 and the potential of such regulation for treatment of chronic inflammation.
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Affiliation(s)
- Charlene Siew-Hon Tan
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Yee-Kong Ng
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore. .,Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore.
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Shin EJ, Jeong JH, Chung CK, Kim DJ, Wie MB, Park ES, Chung YH, Nam Y, Tran TV, Lee SY, Kim HJ, Ong WY, Kim HC. Ceruloplasmin is an endogenous protectant against kainate neurotoxicity. Free Radic Biol Med 2015; 84:355-372. [PMID: 25843655 DOI: 10.1016/j.freeradbiomed.2015.03.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2015] [Revised: 03/10/2015] [Accepted: 03/14/2015] [Indexed: 01/08/2023]
Abstract
To determine the role of ceruloplasmin (Cp) in epileptic seizures, we used a kainate (KA) seizure animal model and examined hippocampal samples from epileptic patients. Treatment with KA resulted in a time-dependent decrease in Cp protein expression in the hippocampus of rats. Cp-positive cells were colocalized with neurons or reactive astrocytes in KA-treated rats and epileptic patient samples. KA-induced seizures, initial oxidative stress (i.e., hydroxyl radical formation, lipid peroxidation, protein oxidation, and synaptosomal reactive oxygen species), altered iron status (increasing Fe(2+) accumulation and L-ferritin-positive reactive microglial cells and decreasing H-ferritin-positive neurons), and impaired glutathione homeostasis and neurodegeneration (i.e., Fluoro-Nissl and Fluoro-Jade B staining analyses) were more pronounced in Cp antisense oligonucleotide (ASO)- than in Cp sense oligonucleotide-treated rats. Consistently, Cp ASO facilitated KA-induced lactate dehydrogenase (LDH) release, Fe(2+) accumulation, and glutathione loss in neuron-rich and mixed cultures. However, Cp ASO did not alter KA-induced LDH release or Fe(2+) accumulation in the astroglial culture, but did facilitate impairment in glutathione homeostasis in the same culture. Importantly, treatment with human Cp protein resulted in a significant attenuation against these neurotoxicities induced by Cp ASO. Our results suggest that Cp-mediated neuroprotection occurs via the inhibition of seizure-associated oxidative damage (including impairment in glutathione homeostasis), Fe(2+) accumulation, and alterations in ferritin immunoreactivity. Moreover, interactive modulation between neurons and glia was found to be important for Cp upregulation in the attenuation of epileptic damage in both animals and humans.
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Affiliation(s)
- Eun-Joo Shin
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - Ji Hoon Jeong
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | - Chun Kee Chung
- Department of Neurosurgery, Seoul National University College of Medicine, Seoul National University Hospital, Seoul 110-799, South Korea
| | - Dae-Joong Kim
- Department of Anatomy and Cell Biology, Medical School, Kangwon National University, Chunchon 200-701, South Korea
| | - Myung-Bok Wie
- Department of Veterinary Medicine, Kangwon National University, Chunchon 200-701, South Korea
| | - Eon Sub Park
- Department of Pathology, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | - Yoon Hee Chung
- Department of Anatomy, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | - Yunsung Nam
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - The-Vinh Tran
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - Sung Youl Lee
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - Hwa-Jung Kim
- College of Pharmacy, Ewha Women׳s University, Seoul 120-750, South Korea
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore 119260, Singapore
| | - Hyoung-Chun Kim
- Neuropsychopharmacology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea.
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Ong WY, Shalini SM, Costantino L. Nose-to-brain drug delivery by nanoparticles in the treatment of neurological disorders. Curr Med Chem 2015; 21:4247-56. [PMID: 25039773 DOI: 10.2174/0929867321666140716103130] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/02/2014] [Accepted: 07/11/2014] [Indexed: 11/22/2022]
Abstract
Many potential drugs for the treatment of neurological diseases are unable to reach the brain in sufficient enough concentrations to be therapeutic because of the blood brain barrier. On the other hand, direct delivery of drugs to the brain provides the possibility of a greater therapeutic-toxic ratio than with systemic drug delivery. The use of intranasal delivery of therapeutic agents to the brain provides a means of bypassing the blood brain barrier in a non-invasive manner. In this respect, nanosized drug carriers were shown to enhance the delivery of drugs to CNS compared to equivalent drug solution formulations. Neurological conditions that have been studied in animal models that could benefit from nose-to-brain delivery of nanotherapeutics include pain, epilepsy, neurodegenerative disease and infectious diseases. The delivery of drugs to the brain via the nose-to-brain route holds great promise, on the basis of preclinical research by means of drug delivery systems such as polymeric nanoparticles and clinical data related to intranasal delivery to CNS of large molecular weight biologics administered in solution, but safety issues about toxicity on nasal mucosa, Np transport into the brain, delivery only to specific brain regions and variability in the adsorbed dose still represent research topics that need to be considered, with a view of clinical translation of these delivery systems.
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Affiliation(s)
| | | | - Luca Costantino
- Department of Anatomy, National University of Singapore, Singapore 117597.
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47
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Ong WY, Farooqui T, Kokotos G, Farooqui AA. Synthetic and natural inhibitors of phospholipases A2: their importance for understanding and treatment of neurological disorders. ACS Chem Neurosci 2015; 6:814-31. [PMID: 25891385 DOI: 10.1021/acschemneuro.5b00073] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Phospholipases A2 (PLA2) are a diverse group of enzymes that hydrolyze membrane phospholipids into arachidonic acid and lysophospholipids. Arachidonic acid is metabolized to eicosanoids (prostaglandins, leukotrienes, thromboxanes), and lysophospholipids are converted to platelet-activating factors. These lipid mediators play critical roles in the initiation, maintenance, and modulation of neuroinflammation and oxidative stress. Neurological disorders including excitotoxicity; traumatic nerve and brain injury; cerebral ischemia; Alzheimer's disease; Parkinson's disease; multiple sclerosis; experimental allergic encephalitis; pain; depression; bipolar disorder; schizophrenia; and autism are characterized by oxidative stress, inflammatory reactions, alterations in phospholipid metabolism, accumulation of lipid peroxides, and increased activities of brain phospholipase A2 isoforms. Several old and new synthetic inhibitors of PLA2, including fatty acid trifluoromethyl ketones; methyl arachidonyl fluorophosphonate; bromoenol lactone; indole-based inhibitors; pyrrolidine-based inhibitors; amide inhibitors, 2-oxoamides; 1,3-disubstituted propan-2-ones and polyfluoroalkyl ketones as well as phytochemical based PLA2 inhibitors including curcumin, Ginkgo biloba and Centella asiatica extracts have been discovered and used for the treatment of neurological disorders in cell culture and animal model systems. The purpose of this review is to summarize information on selective and potent synthetic inhibitors of PLA2 as well as several PLA2 inhibitors from plants, for treatment of oxidative stress and neuroinflammation associated with the pathogenesis of neurological disorders.
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Affiliation(s)
- Wei-Yi Ong
- Department
of Anatomy, National University of Singapore, Singapore 119260, Singapore
| | - Tahira Farooqui
- Department
of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
| | - George Kokotos
- Laboratory
of Organic Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis,
Athens 15771, Greece
| | - Akhlaq A. Farooqui
- Department
of Molecular and Cellular Biochemistry, Ohio State University, Columbus, Ohio 43210, United States
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van Eersel J, Stevens CH, Przybyla M, Gladbach A, Stefanoska K, Chan CKX, Ong WY, Hodges JR, Sutherland GT, Kril JJ, Abramowski D, Staufenbiel M, Halliday GM, Ittner LM. Early-onset axonal pathology in a novel P301S-Tau transgenic mouse model of frontotemporal lobar degeneration. Neuropathol Appl Neurobiol 2015; 41:906-25. [DOI: 10.1111/nan.12233] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 02/23/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Janet van Eersel
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Claire H. Stevens
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Magdalena Przybyla
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Amadeus Gladbach
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Kristie Stefanoska
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Chesed Kai-Xin Chan
- Department of Anatomy; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - Wei-Yi Ong
- Department of Anatomy; Yong Loo Lin School of Medicine; National University of Singapore; Singapore
| | - John R. Hodges
- Neuroscience Research Australia; Sydney Australia
- Faculty of Medicine; University of New South Wales; Sydney Australia
| | | | - Jillian J. Kril
- Discipline of Pathology; University of Sydney; Sydney Australia
| | | | | | - Glenda M. Halliday
- Neuroscience Research Australia; Sydney Australia
- Faculty of Medicine; University of New South Wales; Sydney Australia
| | - Lars M. Ittner
- Dementia Research Unit; Department of Anatomy; School of Medical Sciences; Faculty of Medicine; University of New South Wales; Sydney Australia
- Neuroscience Research Australia; Sydney Australia
- Sydney Medical School; University of Sydney; Sydney Australia
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Chia WJ, Tan FCK, Ong WY, Dawe GS. Expression and localisation of brain-type organic cation transporter (BOCT/24p3R/LCN2R) in the normal rat hippocampus and after kainate-induced excitotoxicity. Neurochem Int 2015; 87:43-59. [PMID: 26004810 DOI: 10.1016/j.neuint.2015.04.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 04/06/2015] [Accepted: 04/14/2015] [Indexed: 01/13/2023]
Abstract
The iron siderophore binding protein lipocalin 2 (LCN2, also known as 24p3, NGAL and siderocalin) may be involved in iron homeostasis, but to date, little is known about expression of its putative receptor, brain-type organic cation transporter (BOCT, also known as BOCT1, 24p3R, NGALR and LCN2R), in the brain during neurodegeneration. The present study was carried out to elucidate the expression of LCN2 and BOCT in hippocampus after excitotoxicity induced by the glutamate analog, kainate (KA) and a possible role of LCN2 in neuronal injury. As reported previously, a rapid and sustained induction in expression of LCN2 was found in the hippocampus after intracerebroventicular injection of KA. BOCT was expressed in neurons of the saline-injected control hippocampus, and immunolabel for BOCT protein was preserved in pyramidal neurons of CA1 at 1 day post-KA injection, likely due to the delayed onset of neurodegeneration after KA injection. At 3 days and 2 weeks after KA injections, loss of immunolabel was observed due to degenerated neurons, although remaining neurons continued to express BOCT, and induction of BOCT was found in OX-42 positive microglia. This resulted in an overall decrease in BOCT mRNA and protein expression after KA treatment. Increased expression of the pro-apoptotic marker, Bim, was found in both neurons and microglia after KA injection, but TUNEL staining indicating apoptosis was found primarily in Bim-expressing neurons, but not microglia. Interaction between LCN2 and BOCT was found by DuoLink assay in cultured hippocampal neurons. Apo-LCN2 without iron caused no significant differences in neuronal Bim expression or cell survival, whereas holo-LCN2 consisting of LCN2:iron:enterochelin complex increased Bim mRNA expression and decreased neuronal survival. Together, results suggest that LCN2 and BOCT may have a role in neuronal injury.
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Affiliation(s)
- Wan-Jie Chia
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, 10 Medical Drive, Singapore 117597; National University of Singapore Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456; Neurobiology and Ageing Programme, Life Sciences Institute, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456
| | - Francis Chee Kuan Tan
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, 10 Medical Drive, Singapore 117597; Neurobiology and Ageing Programme, Life Sciences Institute, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456; Singapore Institute for Neurotechnology (SINAPSE), Centre for Life Sciences, 28 Medical Drive, Singapore 117456
| | - Wei-Yi Ong
- Neurobiology and Ageing Programme, Life Sciences Institute, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456; Department of Anatomy, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, 4 Medical Drive, Singapore 117597.
| | - Gavin S Dawe
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University Health System, National University of Singapore, 10 Medical Drive, Singapore 117597; National University of Singapore Graduate School for Integrative Sciences and Engineering, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456; Neurobiology and Ageing Programme, Life Sciences Institute, Centre for Life Sciences, National University of Singapore, 28 Medical Drive, Singapore 117456; Singapore Institute for Neurotechnology (SINAPSE), Centre for Life Sciences, 28 Medical Drive, Singapore 117456.
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Chew WS, Ong WY. Regulation of Calcium-Independent Phospholipase A2 Expression by Adrenoceptors and Sterol Regulatory Element Binding Protein-Potential Crosstalk Between Sterol and Glycerophospholipid Mediators. Mol Neurobiol 2014; 53:500-517. [PMID: 25482049 DOI: 10.1007/s12035-014-9026-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 11/21/2014] [Indexed: 01/02/2023]
Abstract
Calcium-independent phospholipase A2 (iPLA2) is an 85-kDa enzyme that releases docosahexaenoic acid (DHA) from glycerophospholipids. DHA can be metabolized to resolvins and neuroprotectins that have anti-inflammatory properties and effects on neural plasticity. Recent studies show an important role of prefrontal cortical iPLA2 in hippocampo-prefrontal cortical LTP and antidepressant-like effect of the norepinephrine reuptake inhibitor (NRI) antidepressant, maprotiline. In this study, we elucidated the cellular mechanisms through which stimulation of adrenergic receptors could lead to increased iPLA2 expression. Treatment of SH-SY5Y neuroblastoma cells with maprotiline, another tricyclic antidepressant with noradrenaline reuptake inhibiting properties, nortriptyline, and the adrenergic receptor agonist, phenylephrine, resulted in increased iPLA2β mRNA expression. This increase was blocked by inhibitors to alpha-1 adrenergic receptor, mitogen-activated protein (MAP) kinase or extracellular signal-regulated kinase (ERK) 1/2, and sterol regulatory element-binding protein (SREBP). Maprotiline and phenylephrine induced binding of SREBP-2 to sterol regulatory element (SRE) region on the iPLA2 promoter, as determined by electrophoretic mobility shift assay (EMSA). Together, results indicate that stimulation of adrenoreceptors causes increased iPLA2 expression via MAP kinase/ERK 1/2 and SREBP, and suggest a possible mechanism for effect of CNS noradrenaline on neural plasticity and crosstalk between sterol and glycerophospholipid mediators, that may play a role in physiological or pathophysiological processes in the brain and other organs.
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Affiliation(s)
- Wee-Siong Chew
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore
| | - Wei-Yi Ong
- Department of Anatomy, National University of Singapore, Singapore, 119260, Singapore. .,Neurobiology and Ageing Research Programme, National University of Singapore, Singapore, 119260, Singapore.
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