1
|
Li Y, Ran Q, Duan Q, Jin J, Wang Y, Yu L, Wang C, Zhu Z, Chen X, Weng L, Li Z, Wang J, Wu Q, Wang H, Tian H, Song S, Shan Z, Zhai Q, Qin H, Chen S, Fang L, Yin H, Zhou H, Jiang X, Wang P. 7-Dehydrocholesterol dictates ferroptosis sensitivity. Nature 2024; 626:411-418. [PMID: 38297130 DOI: 10.1038/s41586-023-06983-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 12/15/2023] [Indexed: 02/02/2024]
Abstract
Ferroptosis, a form of regulated cell death that is driven by iron-dependent phospholipid peroxidation, has been implicated in multiple diseases, including cancer1-3, degenerative disorders4 and organ ischaemia-reperfusion injury (IRI)5,6. Here, using genome-wide CRISPR-Cas9 screening, we identified that the enzymes involved in distal cholesterol biosynthesis have pivotal yet opposing roles in regulating ferroptosis through dictating the level of 7-dehydrocholesterol (7-DHC)-an intermediate metabolite of distal cholesterol biosynthesis that is synthesized by sterol C5-desaturase (SC5D) and metabolized by 7-DHC reductase (DHCR7) for cholesterol synthesis. We found that the pathway components, including MSMO1, CYP51A1, EBP and SC5D, function as potential suppressors of ferroptosis, whereas DHCR7 functions as a pro-ferroptotic gene. Mechanistically, 7-DHC dictates ferroptosis surveillance by using the conjugated diene to exert its anti-phospholipid autoxidation function and shields plasma and mitochondria membranes from phospholipid autoxidation. Importantly, blocking the biosynthesis of endogenous 7-DHC by pharmacological targeting of EBP induces ferroptosis and inhibits tumour growth, whereas increasing the 7-DHC level by inhibiting DHCR7 effectively promotes cancer metastasis and attenuates the progression of kidney IRI, supporting a critical function of this axis in vivo. In conclusion, our data reveal a role of 7-DHC as a natural anti-ferroptotic metabolite and suggest that pharmacological manipulation of 7-DHC levels is a promising therapeutic strategy for cancer and IRI.
Collapse
Affiliation(s)
- Yaxu Li
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Qiao Ran
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Qiuhui Duan
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Jiali Jin
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Yanjin Wang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Lei Yu
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Chaojie Wang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Zhenyun Zhu
- Department of Analytical Chemistry, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Xin Chen
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Linjun Weng
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Zan Li
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Jia Wang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Qi Wu
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Hui Wang
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Hongling Tian
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Sihui Song
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Zezhi Shan
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Qiwei Zhai
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, CAS Center for Excellence in Molecular Cell Sciences, Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Huanlong Qin
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Shili Chen
- Shanghai Key Laboratory of Biliary Tract Disease Research, Department of General Surgery, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Lan Fang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China
| | - Huiyong Yin
- CAS Key Laboratory of Nutrition, Metabolism and Food Safety, Shanghai Institute of Nutrition and Health, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Hu Zhou
- Department of Analytical Chemistry, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Xuejun Jiang
- Cell Biology Program, Memorial Sloan-Kettering Cancer Center, New York, NY, USA
| | - Ping Wang
- Tongji University Cancer Center, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China.
- Shanghai Frontiers Science Center of Nanocatalytic Medicine, School of Medicine, Tongji University, Shanghai, China.
| |
Collapse
|
2
|
Zhang DD. Natural inhibitor found for cell death by ferroptosis. Nature 2024; 626:269-270. [PMID: 38297047 DOI: 10.1038/d41586-024-00080-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024]
|
3
|
Chou HD, Shiah SG, Chuang LH, Wu WC, Hwang YS, Chen KJ, Kang EYC, Yeung L, Nien CY, Lai CC. MicroRNA-152-3p and MicroRNA-196a-5p Are Downregulated When Müller Cells Are Promoted by Components of the Internal Limiting Membrane: Implications for Macular Hole Healing. Int J Mol Sci 2023; 24:17188. [PMID: 38139016 PMCID: PMC10743628 DOI: 10.3390/ijms242417188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 11/29/2023] [Accepted: 12/01/2023] [Indexed: 12/24/2023] Open
Abstract
Müller cells play a critical role in the closure of macular holes, and their proliferation and migration are facilitated by the internal limiting membrane (ILM). Despite the importance of this process, the underlying molecular mechanism remains underexplored. This study investigated the effects of ILM components on the microRNA (miRNA) profile of Müller cells. Rat Müller cells (rMC-1) were cultured with a culture insert and varying concentrations of ILM component coatings, namely, collagen IV, laminin, and fibronectin, and cell migration was assessed by measuring cell-free areas in successive photographs following insert removal. MiRNAs were then extracted from these cells and analyzed. Mimics and inhibitors of miRNA candidates were transfected into Müller cells, and a cell migration assay and additional cell viability assays were performed. The results revealed that the ILM components promoted Müller cell migration (p < 0.01). Among the miRNA candidates, miR-194-3p was upregulated, whereas miR-125b-1-3p, miR-132-3p, miR-146b-5p, miR-152-3p, miR-196a-5p, miR-542-5p, miR-871-3p, miR-1839-5p, and miR-3573-3p were significantly downregulated (p < 0.05; fold change > 1.5). Moreover, miR-152-3p and miR-196a-5p reduced cell migration (p < 0.05) and proliferation (p < 0.001), and their suppressive effects were reversed by their respective inhibitors. In conclusion, miRNAs were regulated in ILM component-activated Müller cells, with miR-152-3p and miR-196a-5p regulating Müller cell migration and proliferation. These results serve as a basis for understanding the molecular healing process of macular holes and identifying potential new target genes in future research.
Collapse
Affiliation(s)
- Hung-Da Chou
- Department of Life Sciences, National Central University, Taoyuan 32001, Taiwan; (H.-D.C.); (S.-G.S.)
- Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Main Branch, Taoyuan 33305, Taiwan; (W.-C.W.); (Y.-S.H.); (K.-J.C.); (E.Y.-C.K.)
- College of Medicine, Chang Gung University, Taoyuan 33305, Taiwan; (L.-H.C.); (L.Y.)
- National Institute of Cancer Research, National Health Research Institutes, Miaoli 35053, Taiwan
| | - Shine-Gwo Shiah
- Department of Life Sciences, National Central University, Taoyuan 32001, Taiwan; (H.-D.C.); (S.-G.S.)
- National Institute of Cancer Research, National Health Research Institutes, Miaoli 35053, Taiwan
| | - Lan-Hsin Chuang
- College of Medicine, Chang Gung University, Taoyuan 33305, Taiwan; (L.-H.C.); (L.Y.)
- Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung 20401, Taiwan
| | - Wei-Chi Wu
- Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Main Branch, Taoyuan 33305, Taiwan; (W.-C.W.); (Y.-S.H.); (K.-J.C.); (E.Y.-C.K.)
- College of Medicine, Chang Gung University, Taoyuan 33305, Taiwan; (L.-H.C.); (L.Y.)
| | - Yih-Shiou Hwang
- Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Main Branch, Taoyuan 33305, Taiwan; (W.-C.W.); (Y.-S.H.); (K.-J.C.); (E.Y.-C.K.)
- College of Medicine, Chang Gung University, Taoyuan 33305, Taiwan; (L.-H.C.); (L.Y.)
| | - Kuan-Jen Chen
- Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Main Branch, Taoyuan 33305, Taiwan; (W.-C.W.); (Y.-S.H.); (K.-J.C.); (E.Y.-C.K.)
- College of Medicine, Chang Gung University, Taoyuan 33305, Taiwan; (L.-H.C.); (L.Y.)
| | - Eugene Yu-Chuan Kang
- Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Main Branch, Taoyuan 33305, Taiwan; (W.-C.W.); (Y.-S.H.); (K.-J.C.); (E.Y.-C.K.)
- College of Medicine, Chang Gung University, Taoyuan 33305, Taiwan; (L.-H.C.); (L.Y.)
| | - Ling Yeung
- College of Medicine, Chang Gung University, Taoyuan 33305, Taiwan; (L.-H.C.); (L.Y.)
- Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung 20401, Taiwan
| | - Chung-Yi Nien
- Department of Life Sciences, National Central University, Taoyuan 32001, Taiwan; (H.-D.C.); (S.-G.S.)
| | - Chi-Chun Lai
- Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou Main Branch, Taoyuan 33305, Taiwan; (W.-C.W.); (Y.-S.H.); (K.-J.C.); (E.Y.-C.K.)
- College of Medicine, Chang Gung University, Taoyuan 33305, Taiwan; (L.-H.C.); (L.Y.)
- Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung 20401, Taiwan
| |
Collapse
|
4
|
Mathew B, Acha LG, Torres LA, Huang CC, Liu A, Kalinin S, Leung K, Dai Y, Feinstein DL, Ravindran S, Roth S. MicroRNA-based engineering of mesenchymal stem cell extracellular vesicles for treatment of retinal ischemic disorders: Engineered extracellular vesiclesand retinal ischemia. Acta Biomater 2023; 158:782-797. [PMID: 36638942 PMCID: PMC10005109 DOI: 10.1016/j.actbio.2023.01.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 12/18/2022] [Accepted: 01/05/2023] [Indexed: 01/12/2023]
Abstract
Mesenchymal stem cell (MSCs)-derived extracellular vesicles (EVs) are emerging therapeutic tools. Hypoxic pre-conditioning (HPC) of MSCs altered the production of microRNAs (miRNAs) in EVs, and enhanced the cytoprotective, anti-inflammatory, and neuroprotective properties of their derivative EVs in retinal cells. EV miRNAs were identified as the primary contributors of these EV functions. Through miRNA seq analyses, miRNA-424 was identified as a candidate for the retina to overexpress in EVs for enhancing cytoprotection and anti-inflammatory effects. FEEs (functionally engineered EVs) overexpressing miR424 (FEE424) significantly enhanced neuroprotection and anti-inflammatory activities in vitro in retinal cells. FEE424 functioned by reducing inflammatory cytokine production in retinal microglia, and attenuating oxygen free radicals in retinal Muller cells and microvascular endothelial cells, providing a multi-pronged approach to enhancing recovery after retinal ischemic insult. In an in vivo model of retinal ischemia, native, HPC, and FEE424 MSC EVs robustly and similarly restored function to close to baseline, and prevented loss of retinal ganglion cells, but HPC EVs provided the most effective attenuation of apoptosis-related and inflammatory cytokine gene expression. These results indicate the potential for EV engineering to produce ameliorative effects for retinal diseases with a significant inflammatory component. STATEMENT OF SIGNIFICANCE: We show that functionally engineered extracellular vesicles (FEEs) from mesenchymal stem cells (MSCs) provide cytoprotection in rat retina subjected to ischemia. FEEs overexpressing microRNA 424 (FEE424) function by reducing inflammatory cytokine production in retinal microglia, and attenuating oxygen free radicals in Muller cells and microvascular endothelial cells, providing a multi-pronged approach to enhancing recovery. In an in vivo model of retinal ischemia in rats, native, hypoxic-preconditioned (HPC), and FEE424 MSC EVs robustly and similarly restored function, and prevented loss of retinal ganglion cells, but HPC EVs provided the most effective attenuation of apoptosis-related and inflammatory cytokine gene expression. The results indicate the potential for EV engineering to produce ameliorative effects for retinal diseases with a significant inflammatory component.
Collapse
Affiliation(s)
- Biji Mathew
- Department of Anesthesiology, College of Medicine, University of Illinois-Chicago
| | - Lorea Gamboa Acha
- Department of Anesthesiology, College of Medicine, University of Illinois-Chicago
| | - Leianne A Torres
- Department of Anesthesiology, College of Medicine, University of Illinois-Chicago
| | - Chun-Chieh Huang
- Department of Oral Biology, College of Dentistry, University of Illinois-Chicago
| | - Alice Liu
- Department of Anesthesiology, College of Medicine, University of Illinois-Chicago
| | - Sergey Kalinin
- Department of Anesthesiology, College of Medicine, University of Illinois-Chicago
| | - Kasey Leung
- Department of Oral Biology, College of Dentistry, University of Illinois-Chicago
| | - Yang Dai
- Department of Bioengineering, College of Engineering, University of Illinois-Chicago
| | - Douglas L Feinstein
- Department of Anesthesiology, College of Medicine, University of Illinois-Chicago; Jesse Brown Veterans Affairs, Chicago, IL
| | - Sriram Ravindran
- Department of Oral Biology, College of Dentistry, University of Illinois-Chicago.
| | - Steven Roth
- Department of Anesthesiology, College of Medicine, University of Illinois-Chicago.
| |
Collapse
|
5
|
Farkas MH, Skelton LA, Ramachandra-Rao S, Au E, Fliesler SJ. Morphological, biochemical, and transcriptomic characterization of iPSC-derived human RPE cells from normal and Smith-Lemli-Opitz syndrome patients. Mol Vis 2022; 28:394-411. [PMID: 36540063 PMCID: PMC9744241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 11/11/2022] [Indexed: 12/30/2022] Open
Affiliation(s)
- Michael H. Farkas
- Department of Ophthalmology (Ross Eye Institute), The State University of New York- University at Buffalo, Buffalo, NY,Department of Biochemistry and the Neuroscience Graduate Program, The State University of New York- University at Buffalo, Buffalo, NY,Research Service, VA Western New York Healthcare System, Buffalo, NY
| | - Lara A. Skelton
- Department of Ophthalmology (Ross Eye Institute), The State University of New York- University at Buffalo, Buffalo, NY,Department of Biochemistry and the Neuroscience Graduate Program, The State University of New York- University at Buffalo, Buffalo, NY,Research Service, VA Western New York Healthcare System, Buffalo, NY
| | - Sriganesh Ramachandra-Rao
- Department of Ophthalmology (Ross Eye Institute), The State University of New York- University at Buffalo, Buffalo, NY,Department of Biochemistry and the Neuroscience Graduate Program, The State University of New York- University at Buffalo, Buffalo, NY,Research Service, VA Western New York Healthcare System, Buffalo, NY
| | - Elizabeth Au
- Department of Ophthalmology (Ross Eye Institute), The State University of New York- University at Buffalo, Buffalo, NY
| | - Steven J. Fliesler
- Department of Ophthalmology (Ross Eye Institute), The State University of New York- University at Buffalo, Buffalo, NY,Department of Biochemistry and the Neuroscience Graduate Program, The State University of New York- University at Buffalo, Buffalo, NY,Research Service, VA Western New York Healthcare System, Buffalo, NY
| |
Collapse
|
6
|
Korade Z, Tallman KA, Kim HYH, Balog M, Genaro-Mattos TC, Pattnaik A, Mirnics K, Pattnaik AK, Porter NA. Dose-Response Effects of 7-Dehydrocholesterol Reductase Inhibitors on Sterol Profiles and Vesicular Stomatitis Virus Replication. ACS Pharmacol Transl Sci 2022; 5:1086-1096. [PMID: 36407960 PMCID: PMC9667548 DOI: 10.1021/acsptsci.2c00051] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Indexed: 11/29/2022]
Abstract
Cholesterol is ubiquitous in cells; it plays a critical role in membrane structure and transport as well as in intracellular trafficking processes. There are suggestions that cholesterol metabolism is linked to innate immunity with inhibitors of DHCR7, the last enzyme in the cholesterol pathway, suggested to have potential as viral therapeutics nearly a decade ago. In fact, there are a number of highly prescribed pharmaceuticals that are off-target inhibitors of DHCR7, causing increased cellular levels of 7-dehydrodesmosterol (7-DHD) and 7-dehydrocholesterol (7-DHC). We report here dose-response studies of six such inhibitors on late-stage cholesterol biosynthesis in Neuro2a cells as well as their effect on infection of vesicular stomatitis virus (VSV). Four of the test compounds are FDA-approved drugs (cariprazine, trazodone, metoprolol, and tamoxifen), one (ifenprodil) has been the object of a recent Phase 2b COVID trial, and one (AY9944) is an experimental compound that has seen extensive use as a DHCR7 inhibitor. The three FDA-approved drugs inhibit replication of a GFP-tagged VSV with efficacies that mirror their effect on DHCR7. Ifenprodil and AY9944 have complex inhibitory profiles, acting on both DHCR7 and DHCR14, while tamoxifen does not inhibit DHCR7 and is toxic to Neuro2a at concentrations where it inhibits the Δ7-Δ8 isomerase of the cholesterol pathway. VSV itself affects the sterol profile in Neuro2a cells, showing a dose-response increase of dehydrolathosterol and lathosterol, the substrates for DHCR7, with a corresponding decrease in desmosterol and cholesterol. 7-DHD and 7-DHC are orders of magnitude more vulnerable to free radical chain oxidation than other sterols as well as polyunsaturated fatty esters, and the effect of these sterols on viral infection is likely a reflection of this fact of Nature.
Collapse
Affiliation(s)
- Zeljka Korade
- Department
of Pediatrics, Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska 68198, United States
| | - Keri A. Tallman
- Department
of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Hye-Young H. Kim
- Department
of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Marta Balog
- Munroe-Meyer
Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68105, United States
- Department
of Medical Biology and Genetics, Faculty of Medicine, J. J. Strossmayer University of Osijek, Osijek 31000, Croatia
| | - Thiago C. Genaro-Mattos
- Munroe-Meyer
Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68105, United States
| | - Aryamav Pattnaik
- Nebraska
Center for Virology and School of Veterinary Medicine and Biomedical
Sciences, University of Nebraska-Lincoln, Lincoln 68583, United States
| | - Károly Mirnics
- Munroe-Meyer
Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68105, United States
| | - Asit K. Pattnaik
- Nebraska
Center for Virology and School of Veterinary Medicine and Biomedical
Sciences, University of Nebraska-Lincoln, Lincoln 68583, United States
| | - Ned A. Porter
- Department
of Chemistry, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| |
Collapse
|
7
|
Balog M, Anderson AC, Heffer M, Korade Z, Mirnics K. Effects of Psychotropic Medication on Somatic Sterol Biosynthesis of Adult Mice. Biomolecules 2022; 12:biom12101535. [PMID: 36291744 PMCID: PMC9599595 DOI: 10.3390/biom12101535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 10/12/2022] [Accepted: 10/18/2022] [Indexed: 11/21/2022] Open
Abstract
Polypharmacy is commonly used to treat psychiatric disorders. These combinations often include drugs with sterol biosynthesis inhibiting side effects, including the antipsychotic aripiprazole (ARI), and antidepressant trazodone (TRZ). As the effects of psychotropic medications are poorly understood across the various tissue types to date, we investigated the effects of ARI, TRZ, and ARI + TRZ polypharmacy on the post-lanosterol biosynthesis in three cell lines (Neuro2a, HepG2, and human dermal fibroblasts) and seven peripheral tissues of an adult mouse model. We found that both ARI and TRZ strongly interfere with the function of 7-dehydrocholesterol reductase enzyme (DHCR7) and lead to robust elevation in 7-dehydrocholesterol levels (7-DHC) and reduction in desmosterol (DES) across all cell lines and somatic tissues. ARI + TRZ co-administration resulted in summative or synergistic effects across the utilized in vitro and in vivo models. These findings suggest that at least some of the side effects of ARI and TRZ are not receptor mediated but arise from inhibiting DHCR7 enzyme activity. We propose that interference with sterol biosynthesis, particularly in the case of simultaneous utilization of medications with such side effects, can potentially interfere with functioning or development of multiple organ systems, warranting further investigation.
Collapse
Affiliation(s)
- Marta Balog
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE 68105, USA
- Department of Medical Biology and Genetics, Faculty of Medicine, J. J. Strossmayer University of Osijek, 31000 Osijek, Croatia
| | - Allison C Anderson
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE 68105, USA
| | - Marija Heffer
- Department of Medical Biology and Genetics, Faculty of Medicine, J. J. Strossmayer University of Osijek, 31000 Osijek, Croatia
| | - Zeljka Korade
- Department of Pediatrics, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Child Health Research Institute, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Correspondence: (Z.K.); (K.M.)
| | - Karoly Mirnics
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE 68105, USA
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Child Health Research Institute, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Psychiatry, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Pharmacology and Experimental Neuroscience, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Correspondence: (Z.K.); (K.M.)
| |
Collapse
|
8
|
Allen LB, Mirnics K. Metoprolol Inhibits Developmental Brain Sterol Biosynthesis in Mice. Biomolecules 2022; 12:1211. [PMID: 36139049 PMCID: PMC9496459 DOI: 10.3390/biom12091211] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/26/2022] [Accepted: 08/28/2022] [Indexed: 12/29/2022] Open
Abstract
De novo sterol synthesis is a critical homeostatic mechanism in the brain that begins during early embryonic development and continues throughout life. Multiple medications have sterol-biosynthesis-inhibiting side effects, with potentially detrimental effects on brain health. Using LC-MS/MS, we investigated the effects of six commonly used beta-blockers on brain sterol biosynthesis in vitro using cell lines. Two beta-blockers, metoprolol (MTP) and nebivolol, showed extreme elevations of the highly oxidizable cholesterol precursor 7-dehydrocholesterol (7-DHC) in vitro across multiple cell lines. We followed up on the MTP findings using a maternal exposure model in mice. We found that 7-DHC was significantly elevated in all maternal brain regions analyzed as well as in the heart, liver and brain of the maternally exposed offspring. Since DHCR7-inhibiting/7-DHC elevating compounds can be considered teratogens, these findings suggest that MTP utilization during pregnancy might be detrimental for the development of offspring, and alternative beta-blockers should be considered.
Collapse
Affiliation(s)
- Luke B. Allen
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE 68105, USA
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Károly Mirnics
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE 68105, USA
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Pharmacology and Experimental Neuroscience, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Department of Psychiatry, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| |
Collapse
|
9
|
Balog M, Anderson A, Genaro-Mattos TC, Korade Z, Mirnics K. Individual and simultaneous treatment with antipsychotic aripiprazole and antidepressant trazodone inhibit sterol biosynthesis in the adult brain. J Lipid Res 2022; 63:100249. [PMID: 35839864 PMCID: PMC9386463 DOI: 10.1016/j.jlr.2022.100249] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 06/29/2022] [Accepted: 06/30/2022] [Indexed: 11/29/2022] Open
Abstract
Polypharmacy, or the simultaneous use of multiple drugs to treat a single patient, is a common practice in psychiatry. Unfortunately, data on the health effects of commonly used combinations of medications are very limited. In this study, we therefore investigated the effects and interactions between two commonly prescribed psychotropic medications with sterol inhibiting side effects, trazodone (TRZ), an antidepressant, and aripiprazole (ARI), an antipsychotic. In vitro cell culture experiments revealed that both medications alone disrupted neuronal and astroglial sterol biosynthesis in dose-dependent manners. Furthermore, when ARI and TRZ were combined, exposure resulted in an additive 7-dehydrocholesterol (7-DHC) increase, as well as desmosterol (DES) and cholesterol decreases in both cell types. In adult mice, at baseline, we found that the three investigated sterols showed significant differences in distribution across the eight assessed brain regions. Furthermore, experimental mice treated with ARI or TRZ, or a combination of both medications for 8 days, showed strong sterol disruption across all brain regions. We show ARI or TRZ alone elevated 7-DHC and decreased DES levels in all brain regions, but with regional differences. However, the combined utilization of these two medications for 8 days did not lead to additive changes in sterol disturbances. Based on the complex roles of 7-DHC derived oxysterols, we conclude that individual and potentially simultaneous use of medications with sterol biosynthesis-inhibiting properties might have undesired side effects on the adult brain, with as yet unknown long-term consequences on mental or physical health.
Collapse
Affiliation(s)
- Marta Balog
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska, USA; Faculty of Medicine, Department of Medical Biology and Genetics, J. J. Strossmayer University of Osijek, Osijek, Croatia
| | - Allison Anderson
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Thiago C Genaro-Mattos
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska, USA
| | - Zeljka Korade
- Department of Pediatrics, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA; Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA.
| | - Karoly Mirnics
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska, USA; Department of Pediatrics, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA; Department of Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, Nebraska, USA.
| |
Collapse
|
10
|
Daggubati V, Raleigh DR, Sever N. Sterol regulation of developmental and oncogenic Hedgehog signaling. Biochem Pharmacol 2022; 196:114647. [PMID: 34111427 PMCID: PMC8648856 DOI: 10.1016/j.bcp.2021.114647] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/02/2021] [Accepted: 06/04/2021] [Indexed: 02/03/2023]
Abstract
The Hedgehog (Hh) family of lipid-modified signaling proteins directs embryonic tissue patterning and postembryonic tissue homeostasis, and dysregulated Hh signaling drives familial and sporadic cancers. Hh ligands bind to and inhibit the tumor suppressor Patched and allow the oncoprotein Smoothened (SMO) to accumulate in cilia, which in turn activates the GLI family of transcription factors. Recent work has demonstrated that endogenous cholesterol and oxidized cholesterol derivatives (oxysterols) bind and modulate SMO activity. Here we discuss the myriad sterols that activate or inhibit the Hh pathway, with emphasis on endogenous 24(S),25-epoxycholesterol and 3β,5α-dihydroxycholest-7-en-6-one, and propose models of sterol regulation of SMO. Synthetic inhibitors of SMO have long been the focus of drug development efforts. Here, we discuss the possible utility of steroidal SMO ligands or inhibitors of enzymes involved in sterol metabolism as cancer therapeutics.
Collapse
Affiliation(s)
- Vikas Daggubati
- Departments of Radiation Oncology and Neurological Surgery, and Biomedical Sciences Graduate Program, University of California, San Francisco, CA, USA,Medical Scientist Training Program, University of California, San Francisco, CA, USA
| | - David R. Raleigh
- Departments of Radiation Oncology and Neurological Surgery, and Biomedical Sciences Graduate Program, University of California, San Francisco, CA, USA
| | - Navdar Sever
- Department of Cell Biology, Harvard Medical School, Boston, MA, USA,Corresponding author: Navdar Sever, Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, LHRRB 405, Boston, MA 02115, USA, , Telephone: (617) 432-1612
| |
Collapse
|
11
|
Korade Z, Heffer M, Mirnics K. Medication effects on developmental sterol biosynthesis. Mol Psychiatry 2022; 27:490-501. [PMID: 33820938 PMCID: PMC8490477 DOI: 10.1038/s41380-021-01074-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/01/2021] [Accepted: 03/19/2021] [Indexed: 02/01/2023]
Abstract
Cholesterol is essential for normal brain function and development. Genetic disruptions of sterol biosynthesis result in intellectual and developmental disabilities. Developing neurons synthesize their own cholesterol, and disruption of this process can occur by both genetic and chemical mechanisms. Many commonly prescribed medications interfere with sterol biosynthesis, including haloperidol, aripiprazole, cariprazine, fluoxetine, trazodone and amiodarone. When used during pregnancy, these compounds might have detrimental effects on the developing brain of the offspring. In particular, inhibition of dehydrocholesterol-reductase 7 (DHCR7), the last enzyme in the biosynthesis pathway, results in accumulation of the immediate cholesterol precursor, 7-dehydrocholesterol (7-DHC). 7-DHC is highly unstable, giving rise to toxic oxysterols; this is particularly pronounced in a mouse model when both the mother and the offspring carry the Dhcr7+/- genotype. Studies of human dermal fibroblasts from individuals who carry DCHR7+/- single allele mutations suggest that the same gene*medication interaction also occurs in humans. The public health relevance of these findings is high, as DHCR7-inhibitors can be considered teratogens, and are commonly used by pregnant women. In addition, sterol biosynthesis inhibiting medications should be used with caution in individuals with mutations in sterol biosynthesis genes. In an age of precision medicine, further research in this area could open opportunities to improve patient and fetal/infant safety by tailoring medication prescriptions according to patient genotype and life stage.
Collapse
Affiliation(s)
- Zeljka Korade
- Department of Pediatrics, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA, 68198.,Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA, 68198
| | - Marija Heffer
- J. J. Strossmayer University of Osijek, Faculty of Medicine Osijek, Department of Medical Biology and Genetics, Josipa Huttlera 4, 31000 Osijek, Croatia
| | - Károly Mirnics
- Biochemistry and Molecular Biology, College of Medicine, University of Nebraska Medical Center, Omaha, NE, 68198, USA. .,Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE, 68105, USA.
| |
Collapse
|
12
|
Abstract
Cholesterol is a quantitatively and biologically significant constituent of all mammalian cell membrane, including those that comprise the retina. Retinal cholesterol homeostasis entails the interplay between de novo synthesis, uptake, intraretinal sterol transport, metabolism, and efflux. Defects in these complex processes are associated with several congenital and age-related disorders of the visual system. Herein, we provide an overview of the following topics: (a) cholesterol synthesis in the neural retina; (b) lipoprotein uptake and intraretinal sterol transport in the neural retina and the retinal pigment epithelium (RPE); (c) cholesterol efflux from the neural retina and the RPE; and (d) biology and pathobiology of defects in sterol synthesis and sterol oxidation in the neural retina and the RPE. We focus, in particular, on studies involving animal models of monogenic disorders pertinent to the above topics, as well as in vitro models using biochemical, metabolic, and omic approaches. We also identify current knowledge gaps and opportunities in the field that beg further research in this topic area.
Collapse
Affiliation(s)
- Sriganesh Ramachandra Rao
- Departments of Ophthalmology and Biochemistry and Neuroscience Graduate Program, Jacobs School of Medicine and Biomedical Sciences, State University of New York- University at Buffalo, Buffalo, NY, USA; Research Service, VA Western NY Healthcare System, Buffalo, NY, USA
| | - Steven J Fliesler
- Departments of Ophthalmology and Biochemistry and Neuroscience Graduate Program, Jacobs School of Medicine and Biomedical Sciences, State University of New York- University at Buffalo, Buffalo, NY, USA; Research Service, VA Western NY Healthcare System, Buffalo, NY, USA.
| |
Collapse
|
13
|
Zhang X, Alhasani RH, Zhou X, Reilly J, Zeng Z, Strang N, Shu X. Oxysterols and retinal degeneration. Br J Pharmacol 2021; 178:3205-3219. [PMID: 33501641 DOI: 10.1111/bph.15391] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 01/13/2021] [Accepted: 01/19/2021] [Indexed: 12/11/2022] Open
Abstract
Retinal degeneration, characterised by the progressive death of retinal neurons, is the most common cause of visual impairment. Oxysterols are the cholesterol derivatives produced via enzymatic and/or free radical oxidation that regulate cholesterol homeostasis in the retina. Preclinical and clinical studies have suggested a connection between oxysterols and retinal degeneration. Here, we summarise early and recent work related to retina oxysterol-producing enzymes and the distribution of oxysterols in the retina. We examine the impact of loss of oxysterol-producing enzymes on retinal pathology and explore the molecular mechanisms associated with the toxic or protective roles of individual oxysterols in different types of retinal degeneration. We conclude that increased efforts to better understand the oxysterol-associated pathophysiology will help in the development of effective retinal degeneration therapies. LINKED ARTICLES: This article is part of a themed issue on Oxysterols, Lifelong Health and Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.16/issuetoc.
Collapse
Affiliation(s)
- Xun Zhang
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Reem Hasaballah Alhasani
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, UK.,Department of Biology, Faculty of Applied Science, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Xinzhi Zhou
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, UK
| | - James Reilly
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, UK
| | - Zhihong Zeng
- College of Biological and Environmental Engineering, Changsha University, Changsha, Hunan, China
| | - Niall Strang
- Department of Vision Science, Glasgow Caledonian University, Glasgow, UK
| | - Xinhua Shu
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, UK.,Department of Vision Science, Glasgow Caledonian University, Glasgow, UK.,School of Basic Medical Sciences, Shaoyang University, Shaoyang, Hunan, China
| |
Collapse
|
14
|
Transcriptomic Changes Associated with Loss of Cell Viability Induced by Oxysterol Treatment of a Retinal Photoreceptor-Derived Cell Line: An In Vitro Model of Smith-Lemli-Opitz Syndrome. Int J Mol Sci 2021; 22:ijms22052339. [PMID: 33652836 PMCID: PMC7956713 DOI: 10.3390/ijms22052339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/19/2021] [Accepted: 02/21/2021] [Indexed: 11/17/2022] Open
Abstract
Smith–Lemli–Opitz Syndrome (SLOS) results from mutations in the gene encoding the enzyme DHCR7, which catalyzes conversion of 7-dehydrocholesterol (7DHC) to cholesterol (CHOL). Rats treated with a DHCR7 inhibitor serve as a SLOS animal model, and exhibit progressive photoreceptor-specific cell death, with accumulation of 7DHC and oxidized sterols. To understand the basis of this cell type specificity, we performed transcriptomic analyses on a photoreceptor-derived cell line (661W), treating cells with two 7DHC-derived oxysterols, which accumulate in tissues and bodily fluids of SLOS patients and in the rat SLOS model, as well as with CHOL (negative control), and evaluated differentially expressed genes (DEGs) for each treatment. Gene enrichment analysis and compilation of DEG sets indicated that endoplasmic reticulum stress, oxidative stress, DNA damage and repair, and autophagy were all highly up-regulated pathways in oxysterol-treated cells. Detailed analysis indicated that the two oxysterols exert their effects via different molecular mechanisms. Changes in expression of key genes in highlighted pathways (Hmox1, Ddit3, Trib3, and Herpud1) were validated by immunofluorescence confocal microscopy. The results extend our understanding of the pathobiology of retinal degeneration and SLOS, identifying potential new druggable targets for therapeutic intervention into these and other related orphan diseases.
Collapse
|
15
|
Tallman KA, Allen LB, Klingelsmith KB, Anderson A, Genaro-Mattos TC, Mirnics K, Porter NA, Korade Z. Prescription Medications Alter Neuronal and Glial Cholesterol Synthesis. ACS Chem Neurosci 2021; 12:735-745. [PMID: 33528983 PMCID: PMC7977035 DOI: 10.1021/acschemneuro.0c00765] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Mouse brain contains over 100 million neuronal, glial, and other support cells. Developing neurons and astrocytes synthesize their own cholesterol, and disruption of this process can occur by both genetic and chemical mechanisms. In this study we have exposed cultured murine neurons and astrocytes to six different prescription medications that cross the placenta and blood-brain barriers and analyzed the effects of these drugs on cholesterol biosynthesis by an LC-MS/MS protocol that assays 14 sterols and 7 oxysterols in a single run. Three antipsychotics (haloperidol, cariprazine, aripiprazole), two antidepressants (trazodone and sertraline), and an antiarhythmic (amiodarone) inhibited one or more sterol synthesis enzymes. The result of the exposures was a dose-dependent increase in levels of various sterol intermediates and a decreased level of cholesterol in the cultured cells. Four prescription medications (haloperidol, aripiprazole, cariprazine, and trazodone) acted primarily on the DHCR7 enzyme. The result of this exposure was an increase in 7-dehydrocholesterol in neurons and astrocytes to levels that were comparable to those found in cultured neurons and astrocytes from transgenic mice that carried a Dhcr7 pathogenic mutation modeling the neurodevelopmental disorder Smith-Lemli-Opitz syndrome.
Collapse
Affiliation(s)
- Keri A Tallman
- Department of Chemistry, Vanderbilt Institute of Chemical Biology and Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Luke B Allen
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68105, United States
| | - Korinne B Klingelsmith
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68105, United States
| | - Allison Anderson
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68105, United States
| | - Thiago C Genaro-Mattos
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68105, United States
| | - Károly Mirnics
- Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, Nebraska 68105, United States
| | - Ned A Porter
- Department of Chemistry, Vanderbilt Institute of Chemical Biology and Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, Tennessee 37235, United States
| | | |
Collapse
|
16
|
Fliesler SJ. EDITOR'S PERSPECTIVE: On the verge of translation: Combined cholesterol-antioxidant supplementation as a potential therapeutic intervention for Smith-Lemli-Opitz syndrome. Exp Eye Res 2020; 202:108390. [PMID: 33307076 DOI: 10.1016/j.exer.2020.108390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Steven J Fliesler
- Departments of Ophthalmology and Biochemistry and the Neuroscience Graduate Program, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo- the State University of New York, Buffalo, NY, 14215-1129, USA; Research Service, Western New York Healthcare System, Buffalo, NY, 14215-1129, USA.
| |
Collapse
|
17
|
Wu AL, Liu YT, Chou HD, Chuang LH, Chen KJ, Chen YP, Liu L, Yeung L, Wang NK, Hwang YS, Wu WC, Lai CC. Role of growth factors and internal limiting membrane constituents in müller cell migration. Exp Eye Res 2020; 202:108352. [PMID: 33166502 DOI: 10.1016/j.exer.2020.108352] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 10/09/2020] [Accepted: 11/03/2020] [Indexed: 02/06/2023]
Abstract
This study investigated the effects of growth factors and internal limiting membrane components on Müller cell migration. We studied the effects of epidermal growth factor (EGF), fibroblast growth factor (FGF), somatomedin (IGF-1), platelet derived growth factor (PDGF), and stromal cell-derived factor-1 alpha (SDF-1α) as well as collagen IV, laminin, and fibronectin on the proliferative and migratory activities of rat Müller cells in vitro. A water soluble tetrazolium-1 assay was used to quantify the viability of Müller cells in respective cultures, and analysis was performed using an enzyme-linked immunosorbent assay reader. All the factors examined had significant proliferative effects on cultured Müller cells (p < .05). A two-well Ibidi silicone culture insert was used to assess Müller cell migration. Müller cells cultured in EGF, FGF, IGF-1, collagen IV, and laminin but not in SDF, PDGF, or fibronectin effectively increased the cell migratory activity (p < .001). In addition, combined EGF and collagen IV, combined FGF and collagen IV, and combined IGF-1 and laminin exhibited more significant (p < .001) effects on Müller cell migration compared with culture a single factor. In summary, this study revealed the combinatorial effects of various growth factors and individual internal limiting membrane constituents. This may assist Müller cell migration together with the macular hole healing process.
Collapse
Affiliation(s)
- An-Lun Wu
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; Department of Ophthalmology, Mackay Memorial Hospital, Hsinchu, Taiwan
| | - Ya-Tung Liu
- College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Hung-Da Chou
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Lan-Hsin Chuang
- College of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Kuan-Jen Chen
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yen-Po Chen
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Laura Liu
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Ling Yeung
- College of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung, Taiwan
| | - Nan-Kai Wang
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan; Edward S. Harkness Eye Institute, Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Yih-Shiou Hwang
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Wei-Chi Wu
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Chi-Chun Lai
- Department of Ophthalmology, Chang Gung Memorial Hospital, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Ophthalmology, Chang Gung Memorial Hospital, Keelung, Taiwan.
| |
Collapse
|
18
|
Reactive Sterol Electrophiles: Mechanisms of Formation and Reactions with Proteins and Amino Acid Nucleophiles. CHEMISTRY (BASEL, SWITZERLAND) 2020; 2:390-417. [PMID: 35372835 PMCID: PMC8976181 DOI: 10.3390/chemistry2020025] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Radical-mediated lipid oxidation and the formation of lipid hydroperoxides has been a focal point in the investigation of a number of human pathologies. Lipid peroxidation has long been linked to the inflammatory response and more recently, has been identified as the central tenet of the oxidative cell death mechanism known as ferroptosis. The formation of lipid electrophile-protein adducts has been associated with many of the disorders that involve perturbations of the cellular redox status, but the identities of adducted proteins and the effects of adduction on protein function are mostly unknown. Both cholesterol and 7-dehydrocholesterol (7-DHC), which is the immediate biosynthetic precursor to cholesterol, are oxidizable by species such as ozone and oxygen-centered free radicals. Product mixtures from radical chain processes are particularly complex, with recent studies having expanded the sets of electrophilic compounds formed. Here, we describe recent developments related to the formation of sterol-derived electrophiles and the adduction of these electrophiles to proteins. A framework for understanding sterol peroxidation mechanisms, which has significantly advanced in recent years, as well as the methods for the study of sterol electrophile-protein adduction, are presented in this review.
Collapse
|
19
|
Peña JS, Vazquez M. VEGF Upregulates EGFR Expression to Stimulate Chemotactic Behaviors in the rMC-1 Model of Müller Glia. Brain Sci 2020; 10:E330. [PMID: 32485834 PMCID: PMC7348795 DOI: 10.3390/brainsci10060330] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 03/28/2020] [Accepted: 05/27/2020] [Indexed: 12/14/2022] Open
Abstract
Progressive vision loss in adults has become increasingly prevalent worldwide due to retinopathies associated with aging, genetics, and epigenetic factors that damage the retinal microvasculature. Insufficient supply of oxygen and/or nutrients upregulates factors such as vascular endothelial growth factor (VEGF) and epidermal growth factor (EGF), which can induce abnormal angiogenesis and damage the structural arrangement of the retinal blood barrier (BRB). Müller glia (MG) regulate the diffusion of essential compounds across the BRB and respond to retinal insults via reactive gliosis, which includes cell hypertrophy, migration, and/or proliferation near areas of elevated VEGF concentration. Increasing concentrations of exogenous VEGF, upregulated by retinal pigmented epithelium cells, and endogenous epidermal growth factor receptor (EGF-R) stimulation in MG, implicated in MG proliferative and migratory behavior, often lead to progressive and permanent vision loss. Our project examined the chemotactic responses of the rMC-1 cell line, a mammalian MG model, toward VEGF and EGF signaling fields in transwell assays, and within respective concentration gradient fields produced in the glia line (gLL) microfluidic system previously described by our group. rMC-1 receptor expression in defined ligand fields was also evaluated using quantitative polymerase chain reaction (qPCR) and immunocytochemical staining. Results illustrate dramatic increases in rMC-1 chemotactic responses towards EGF gradient fields after pre-treatment with VEGF. In addition, qPCR illustrated significant upregulation of EGF-R upon VEGF pre-treatment, which was higher than that induced by its cognate ligand, EGF. These results suggest interplay of molecular pathways between VEGF and EGF-R that have remained understudied in MG but are significant to the development of effective anti-VEGF treatments needed for a variety of retinopathies.
Collapse
Affiliation(s)
| | - Maribel Vazquez
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA;
| |
Collapse
|
20
|
Pariente A, Pérez-Sala Á, Ochoa R, Peláez R, Larráyoz IM. Genome-Wide Transcriptomic Analysis Identifies Pathways Regulated by Sterculic Acid in Retinal Pigmented Epithelium Cells. Cells 2020; 9:cells9051187. [PMID: 32403229 PMCID: PMC7290791 DOI: 10.3390/cells9051187] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/03/2020] [Accepted: 05/07/2020] [Indexed: 12/13/2022] Open
Abstract
In addition to its predominant role in lipid metabolism and body weight control, SCD1 has emerged recently as a potential new target for the treatment of various diseases. Sterculic acid (SA) is a cyclopropene fatty acid with numerous biological activities, generally attributed to its Stearoyl-CoA desaturase (SCD) inhibitory properties. Additional effects exerted by SA, independently of SCD inhibition, may be mediating anti-inflammatory and protective roles in retinal diseases such as age-related macular degeneration (AMD), but the mechanisms involved are poorly understood. In order to provide insights into those mechanisms, genome-wide transcriptomic analyses were carried out in mRPE cells exposed to SA for 24 h. Integrative functional enrichment analysis of genome-wide expression data provided biological insight about the protective mechanisms induced by SA. On the one hand, pivotal genes related to fatty acid biosynthesis, steroid biosynthesis, cell death, actin-cytoskeleton reorganization and extracellular matrix-receptor interaction were significantly downregulated by exposition to SA. On the other hand, genes related to fatty acid degradation and beta-oxidation were significantly upregulated. In conclusion, SA administration to RPE cells regulates crucial pathways related to cell proliferation, inflammation and cell death that may be of interest for the treatment of ocular diseases.
Collapse
|
21
|
Pariente A, Peláez R, Pérez-Sala Á, Larráyoz IM. Inflammatory and cell death mechanisms induced by 7-ketocholesterol in the retina. Implications for age-related macular degeneration. Exp Eye Res 2019; 187:107746. [DOI: 10.1016/j.exer.2019.107746] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 07/25/2019] [Accepted: 07/25/2019] [Indexed: 12/16/2022]
|
22
|
Speen AM, Hoffman JR, Kim HYH, Escobar YN, Nipp GE, Rebuli ME, Porter NA, Jaspers I. Small Molecule Antipsychotic Aripiprazole Potentiates Ozone-Induced Inflammation in Airway Epithelium. Chem Res Toxicol 2019; 32:1997-2005. [PMID: 31476115 DOI: 10.1021/acs.chemrestox.9b00149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Inhaled ground level ozone (O3) has well described adverse health effects, which may be augmented in susceptible populations. While conditions, such as pre-existing respiratory disease, have been identified as factors enhancing susceptibility to O3-induced health effects, the potential for chemical interactions in the lung to sensitize populations to pollutant-induced responses has not yet been studied. In the airways, inhaled O3 reacts with lipids, such as cholesterol, to generate reactive and electrophilic oxysterol species, capable of causing cellular dysfunction and inflammation. The enzyme regulating the final step of cholesterol biosynthesis, 7-dehydrocholesterol reductase (DHCR7), converts 7-dehydrocholesterol (7-DHC) to cholesterol. Inhibition of DHCR7 increases the levels of 7-DHC, which is much more susceptible to oxidation than cholesterol. Chemical analysis established the capacity for a variety of small molecule antipsychotic drugs, like Aripiprazole (APZ), to inhibit DHCR7 and elevate circulating 7-DHC. Our results show that APZ and the known DHCR7 inhibitor, AY9944, increase 7-DHC levels in airway epithelial cells and potentiate O3-induced IL-6 and IL-8 expression and cytokine release. Targeted immune-related gene array analysis demonstrates that APZ significantly modified O3-induced expression of 16 genes, causing dysregulation in expression of genes associated with leukocyte recruitment and inflammatory response. Additionally, we find that APZ increases O3-induced IL-6 and IL-8 expression in human nasal epithelial cells from male but not female donors. Overall, the evidence we provide describes a novel molecular mechanism by which chemicals, such as APZ, that perturb cholesterol biosynthesis affect O3-induced biological responses.
Collapse
Affiliation(s)
| | | | - Hye-Young H Kim
- Department of Chemistry and Center for Molecular Toxicology , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | | | | | | | - Ned A Porter
- Department of Chemistry and Center for Molecular Toxicology , Vanderbilt University , Nashville , Tennessee 37235 , United States
| | | |
Collapse
|
23
|
Kittipassorn T, Haydinger CD, Wood JPM, Mammone T, Casson RJ, Peet DJ. Characterization of the novel spontaneously immortalized rat Müller cell line SIRMu-1. Exp Eye Res 2019; 181:127-135. [PMID: 30677389 DOI: 10.1016/j.exer.2019.01.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 01/10/2019] [Accepted: 01/10/2019] [Indexed: 10/27/2022]
Abstract
Müller cells (MCs) play a crucial role in the retina, and cultured MC lines are an important tool with which to study MC function. Transformed MC lines have been widely used; however, the transformation process can also lead to unwanted changes compared to the primary cells from which they were derived. To provide an alternative experimental tool, a novel monoclonal spontaneously immortalized rat Müller cell line, SIRMu-1, was derived from primary rat MCs and characterized. Immunofluorescence, western blotting and RNA sequencing demonstrate that the SIRMu-1 cell line retains similar characteristics to cultured primary MCs in terms of expression of the MC markers cellular retinaldehyde-binding protein, glutamine synthetase, S100, vimentin and glial fibrillary acidic protein at both the mRNA and protein levels. Both the cellular morphology and overall transcriptome of the SIRMu-1 cells are more similar to primary rat MCs than the commonly used rMC-1 cells, a well-described, transformed rat MC line. Furthermore, SIRMu-1 cells proliferate rapidly, have an effectively indefinite life span and a high transfection efficiency. The expression of Y chromosome specific genes confirmed that the SIRMu-1 cells are derived from male MCs. Thus, the SIRMu-1 cell line represents a valuable experimental tool to study roles of MCs in both physiological and pathological states.
Collapse
Affiliation(s)
- Thaksaon Kittipassorn
- School of Biological Sciences, Molecular Life Sciences Building, University of Adelaide, Adelaide, SA, 5005, Australia.
| | - Cameron D Haydinger
- School of Biological Sciences, Molecular Life Sciences Building, University of Adelaide, Adelaide, SA, 5005, Australia.
| | - John P M Wood
- Department of Ophthalmology and Visual Sciences, Adelaide Health and Medical Sciences Building, University of Adelaide, Adelaide, SA, 5000, Australia.
| | - Teresa Mammone
- Department of Ophthalmology and Visual Sciences, Adelaide Health and Medical Sciences Building, University of Adelaide, Adelaide, SA, 5000, Australia.
| | - Robert J Casson
- Department of Ophthalmology and Visual Sciences, Adelaide Health and Medical Sciences Building, University of Adelaide, Adelaide, SA, 5000, Australia.
| | - Daniel J Peet
- School of Biological Sciences, Molecular Life Sciences Building, University of Adelaide, Adelaide, SA, 5005, Australia.
| |
Collapse
|
24
|
Fliesler SJ, Xu L. Oxysterols and Retinal Degeneration in a Rat Model of Smith-Lemli-Opitz Syndrome: Implications for an Improved Therapeutic Intervention. Molecules 2018; 23:E2720. [PMID: 30360379 PMCID: PMC6222618 DOI: 10.3390/molecules23102720] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/18/2018] [Accepted: 10/19/2018] [Indexed: 01/31/2023] Open
Abstract
Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive human disease caused by mutations in the gene encoding 7-dehydrocholesterol (7DHC) reductase (DHCR7), resulting in abnormal accumulation of 7DHC and reduced levels of cholesterol in bodily tissues and fluids. A rat model of the disease has been created by treating normal rats with the DHCR7 inhibitor, AY9944, which causes progressive, irreversible retinal degeneration. Herein, we review the features of this disease model and the evidence linking 7DHC-derived oxysterols to the pathobiology of the disease, with particular emphasis on the associated retinal degeneration. A recent study has shown that treating the rat model with cholesterol plus suitable antioxidants completely prevents the retinal degeneration. These findings are discussed with regard to their translational implications for developing an improved therapeutic intervention for SLOS over the current standard of care.
Collapse
Affiliation(s)
- Steven J Fliesler
- Departments of Ophthalmology and Biochemistry and Neuroscience Program, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
- Research Service, VA Western NY Healthcare System, Buffalo, NY 14260, USA.
| | - Libin Xu
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
25
|
Kapphahn RJ, Richards MJ, Ferrington DA, Fliesler SJ. Lipid-derived and other oxidative modifications of retinal proteins in a rat model of Smith-Lemli-Opitz syndrome. Exp Eye Res 2018; 178:247-254. [PMID: 30114413 DOI: 10.1016/j.exer.2018.08.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 08/09/2018] [Accepted: 08/09/2018] [Indexed: 12/23/2022]
Abstract
Oxidative modification of proteins can perturb their structure and function, often compromising cellular viability. Such modifications include lipid-derived adducts (e.g., 4-hydroxynonenal (HNE) and carboxyethylpyrrole (CEP)) as well as nitrotyrosine (NTyr). We compared the retinal proteome and levels of such modifications in the AY9944-treated rat model of Smith-Lemli-Opitz syndrome (SLOS), in comparison to age-matched controls. Retinas harvested at 3 months of age were either subjected to proteomic analysis or to immuno-slot blot analysis, the latter probing blots with antibodies raised against HNE, CEP, and NTyr, followed by quantitative densitometry. HNE modification of retinal proteins was markedly (>9-fold) higher in AY9944-treated rats compared to controls, whereas CEP modification was only modestly (≤2-fold) greater, and NTyr modification was minimal and exhibited no difference as a function of AY9944 treatment. Anti-HNE immunoreactivity was greatest in the plexiform and ganglion cell layers, but also present in the RPE, choroid, and photoreceptor outer segment layer in AY9944-treated rats; control retinas showed minimal HNE labeling. 1D-PAGE/Western blot analysis of rod outer segment (ROS) membranes revealed HNE modification of both opsin and β-transducin. Proteomic analysis revealed the differential expression of several retinal proteins as a consequence of AY9944 treatment. Upregulated proteins included those involved in chaperone/protein folding, oxidative and cellular stress responses, transcriptional regulation, and energy production. βA3/A1 Crystallin, which has a role in regulation of lysosomal acidification, was down-regulated. Hence, oxidative modification of retinal proteins occurs in the SLOS rat model, in addition to the previously described oxidation of lipids. The results are discussed in the context of the histological and physiological changes that occur in the retina in the SLOS rat model.
Collapse
Affiliation(s)
- Rebecca J Kapphahn
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN, USA
| | - Michael J Richards
- Department of Ophthalmology, Saint Louis University, School of Medicine, St. Louis, MO, USA
| | - Deborah A Ferrington
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN, USA
| | - Steven J Fliesler
- Department of Ophthalmology, Saint Louis University, School of Medicine, St. Louis, MO, USA; Departments of Ophthalmology and Biochemistry and the Neuroscience Graduate Program, The State University of New York (SUNY)- University at Buffalo, Buffalo, NY, USA; Research Service, Veterans Administration Western New York Healthcare System (VAWNYHS), Buffalo, NY, USA.
| |
Collapse
|
26
|
Ramachandra Rao S, Pfeffer BA, Más Gómez N, Skelton LA, Keiko U, Sparrow JR, Rowsam AM, Mitchell CH, Fliesler SJ. Compromised phagosome maturation underlies RPE pathology in cell culture and whole animal models of Smith-Lemli-Opitz Syndrome. Autophagy 2018; 14:1796-1817. [PMID: 29979914 PMCID: PMC6135634 DOI: 10.1080/15548627.2018.1490851] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 05/25/2018] [Accepted: 06/11/2018] [Indexed: 12/27/2022] Open
Abstract
Treatment of rats with the cholesterol pathway inhibitor AY9944 produces an animal model of Smith-Lemli-Opitz syndrome (SLOS), an autosomal recessive disease caused by defective cholesterol synthesis. This SLOS rat model undergoes progressive and irreversible degeneration of the neural retina, with associated pathological features of the retinal pigmented epithelium (RPE). Here, we provide further insights into the mechanism involved in the RPE pathology. In the SLOS rat model, markedly increased RPE apical autofluorescence is observed, compared to untreated animals, which correlates with increased levels of A2E and other bisretinoids. Utilizing cultured human induced pluripotent stem cell (iPSC)- derived SLOS RPE cells, we found significantly elevated steady-state levels of 7-dehydrocholesterol (7DHC) and decreased cholesterol levels (key biochemical hallmarks of SLOS). Western blot analysis revealed altered levels of the macroautophagy/autophagy markers MAP1LC3B-II and SQSTM1/p62, and build-up of ubiquitinated proteins. Accumulation of immature autophagosomes was accompanied by inefficient degradation of phagocytized, exogenously supplied retinal rod outer segments (as evidenced by persistence of the C-terminal 1D4 epitope of RHO [rhodopsin]) in SLOS RPE compared to iPSC-derived normal human control. SLOS RPE cells exhibited lysosomal pH levels and CTSD activity within normal physiological limits, thus discounting the involvement of perturbed lysosomal function. Furthermore, 1D4-positive phagosomes that accumulated in the RPE in both pharmacological and genetic rodent models of SLOS failed to fuse with lysosomes. Taken together, these observations suggest that defective phagosome maturation underlies the observed RPE pathology. The potential relevance of these findings to SLOS and the requirement of cholesterol for phagosome maturation are discussed.
Collapse
Affiliation(s)
- Sriganesh Ramachandra Rao
- Departments of Ophthalmology (Ross Eye Institute) and Biochemistry, Jacobs School of Medicine and Biomedical Sciences, SUNY-University at Buffalo, Buffalo, NY, USA
- SUNY Eye Institute, Buffalo, NY, USA
- Research Service, VA Western NY Healthcare System, Buffalo, NY, USA
| | - Bruce A. Pfeffer
- Departments of Ophthalmology (Ross Eye Institute) and Biochemistry, Jacobs School of Medicine and Biomedical Sciences, SUNY-University at Buffalo, Buffalo, NY, USA
- SUNY Eye Institute, Buffalo, NY, USA
- Research Service, VA Western NY Healthcare System, Buffalo, NY, USA
| | - Néstor Más Gómez
- Department of Anatomy & Cell Biology, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA, USA
| | - Lara A. Skelton
- Departments of Ophthalmology (Ross Eye Institute) and Biochemistry, Jacobs School of Medicine and Biomedical Sciences, SUNY-University at Buffalo, Buffalo, NY, USA
- SUNY Eye Institute, Buffalo, NY, USA
- Research Service, VA Western NY Healthcare System, Buffalo, NY, USA
| | - Ueda Keiko
- Departments of Ophthalmology (Harkness Eye Institute) and Pathology & Cell Biology, Columbia University, College of Physicians & Surgeons, NY, NY, USA
| | - Janet R. Sparrow
- Departments of Ophthalmology (Harkness Eye Institute) and Pathology & Cell Biology, Columbia University, College of Physicians & Surgeons, NY, NY, USA
| | - Aryn M. Rowsam
- Departments of Ophthalmology (Ross Eye Institute) and Biochemistry, Jacobs School of Medicine and Biomedical Sciences, SUNY-University at Buffalo, Buffalo, NY, USA
- SUNY Eye Institute, Buffalo, NY, USA
- Research Service, VA Western NY Healthcare System, Buffalo, NY, USA
| | - Claire H. Mitchell
- Department of Anatomy & Cell Biology, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA, USA
| | - Steven J. Fliesler
- Departments of Ophthalmology (Ross Eye Institute) and Biochemistry, Jacobs School of Medicine and Biomedical Sciences, SUNY-University at Buffalo, Buffalo, NY, USA
- SUNY Eye Institute, Buffalo, NY, USA
- Research Service, VA Western NY Healthcare System, Buffalo, NY, USA
| |
Collapse
|
27
|
Fliesler SJ, Peachey NS, Herron J, Hines KM, Weinstock NI, Ramachandra Rao S, Xu L. Prevention of Retinal Degeneration in a Rat Model of Smith-Lemli-Opitz Syndrome. Sci Rep 2018; 8:1286. [PMID: 29352199 PMCID: PMC5775248 DOI: 10.1038/s41598-018-19592-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 01/04/2018] [Indexed: 12/20/2022] Open
Abstract
Smith-Lemli-Opitz Syndrome (SLOS) is a recessive human disease caused by defective cholesterol (CHOL) synthesis at the level of DHCR7 (7-dehydrocholesterol reductase), which normally catalyzes the conversion of 7-dehydrocholesterol (7DHC) to CHOL. Formation and abnormal accumulation of 7DHC and 7DHC-derived oxysterols occur in SLOS patients and in rats treated with the DHCR7 inhibitor AY9944. The rat SLOS model exhibits progressive and irreversible retinal dysfunction and degeneration, which is only partially ameliorated by dietary CHOL supplementation. We hypothesized that 7DHC-derived oxysterols are causally involved in this retinal degeneration, and that blocking or reducing their formation should minimize the phenotype. Here, using the SLOS rat model, we demonstrate that combined dietary supplementation with CHOL plus antioxidants (vitamins E and C, plus sodium selenite) provides better outcomes than dietary CHOL supplementation alone with regard to preservation of retinal structure and function and lowering 7DHC-derived oxysterol formation. These proof-of-principle findings provide a translational, pre-clinical framework for designing clinical trials using CHOL-antioxidant combination therapy as an improved therapeutic intervention over the current standard of care for the treatment of SLOS.
Collapse
Affiliation(s)
- Steven J Fliesler
- Research Service, VA Western New York Healthcare System, Buffalo, NY, USA. .,Departments of Ophthalmology and Biochemistry, and Neuroscience Program, Jacobs School of Medicine & Biomedical Sciences, University at Buffalo- The State University of New York (SUNY), Buffalo, NY, USA. .,SUNY Eye Institute, Buffalo, NY, USA.
| | - Neal S Peachey
- Research Service, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, USA.,Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, OH, USA.,Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA
| | - Josi Herron
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA, USA
| | - Kelly M Hines
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA, USA
| | - Nadav I Weinstock
- Hunter James Kelly Research Institute, Jacobs School of Medicine & Biomedical Sciences, University at Buffalo- The State University of New York (SUNY), Buffalo, NY, USA
| | - Sriganesh Ramachandra Rao
- Research Service, VA Western New York Healthcare System, Buffalo, NY, USA.,Departments of Ophthalmology and Biochemistry, and Neuroscience Program, Jacobs School of Medicine & Biomedical Sciences, University at Buffalo- The State University of New York (SUNY), Buffalo, NY, USA.,SUNY Eye Institute, Buffalo, NY, USA
| | - Libin Xu
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle, WA, USA.
| |
Collapse
|
28
|
Tien T, Zhang J, Muto T, Kim D, Sarthy VP, Roy S. High Glucose Induces Mitochondrial Dysfunction in Retinal Müller Cells: Implications for Diabetic Retinopathy. Invest Ophthalmol Vis Sci 2017; 58:2915-2921. [PMID: 28586916 PMCID: PMC5460955 DOI: 10.1167/iovs.16-21355] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Purpose To investigate whether high glucose (HG) induces mitochondrial dysfunction and promotes apoptosis in retinal Müller cells. Methods Rat retinal Müller cells (rMC-1) grown in normal (N) or HG (30 mM glucose) medium for 7 days were subjected to MitoTracker Red staining to identify the mitochondrial network. Digital images of mitochondria were captured in live cells under confocal microscopy and analyzed for mitochondrial morphology changes based on form factor (FF) and aspect ratio (AR) values. Mitochondrial metabolic function was assessed by measuring oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) using a bioenergetic analyzer. Cells undergoing apoptosis were identified by differential dye staining and TUNEL assay, and cytochrome c levels were assessed by Western blot analysis. Results Cells grown in HG exhibited significantly increased mitochondrial fragmentation compared to those grown in N medium (FF = 1.7 ± 0.1 vs. 2.3 ± 0.1; AR = 2.1 ± 0.1 vs. 2.5 ± 0.2; P < 0.01). OCR and ECAR were significantly reduced in cells grown in HG medium compared to those grown in N medium (steady state: 75% ± 20% of control, P < 0.02; 64% ± 22% of control, P < 0.02, respectively). These cells also exhibited a significant increase (∼2-fold) in the number of apoptotic cells compared to those grown in N medium (P < 0.01), with a concomitant increase in cytochrome c levels (247% ± 94% of control, P < 0.05). Conclusions Findings indicate that HG-induced mitochondrial morphology changes and subsequent mitochondrial dysfunction may contribute to retinal Müller cell loss associated with diabetic retinopathy.
Collapse
Affiliation(s)
- Thomas Tien
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Joyce Zhang
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Tetsuya Muto
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Dongjoon Kim
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Vijay P Sarthy
- Department of Ophthalmology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States
| | - Sayon Roy
- Departments of Medicine and Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| |
Collapse
|
29
|
Kloudova A, Guengerich FP, Soucek P. The Role of Oxysterols in Human Cancer. Trends Endocrinol Metab 2017; 28:485-496. [PMID: 28410994 PMCID: PMC5474130 DOI: 10.1016/j.tem.2017.03.002] [Citation(s) in RCA: 130] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 03/20/2017] [Indexed: 12/12/2022]
Abstract
Oxysterols are oxygenated derivatives of cholesterol formed in the human body or ingested in the diet. By modulating the activity of many proteins [e.g., liver X receptors (LXRs), oxysterol-binding proteins (OSBPs), some ATP-binding cassette (ABC) transporters], oxysterols can affect many cellular functions and influence various physiological processes (e.g., cholesterol metabolism, membrane fluidity regulation, intracellular signaling pathways). Therefore, the role of oxysterols is also important in pathological conditions (e.g., atherosclerosis, diabetes mellitus type 2, neurodegenerative disorders). Finally, current evidence suggests that oxysterols play a role in malignancies such as breast, prostate, colon, and bile duct cancer. This review summarizes the physiological importance of oxysterols in the human body with a special emphasis on their roles in various tumors.
Collapse
Affiliation(s)
- Alzbeta Kloudova
- Department of Toxicogenomics, National Institute of Public Health, Prague 100 42, Czech Republic; Third Faculty of Medicine, Charles University, Prague 100 00, Czech Republic
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
| | - Pavel Soucek
- Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen 323 00, Czech Republic.
| |
Collapse
|
30
|
Streamlined duplex live-dead microplate assay for cultured cells. Exp Eye Res 2017; 161:17-29. [PMID: 28572030 DOI: 10.1016/j.exer.2017.05.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 05/25/2017] [Accepted: 05/25/2017] [Indexed: 11/21/2022]
Abstract
A duplex fluorescence assay to assess the viability of cells cultured in multi-well plates is described, which can be carried out in the original culture plate using a plate reader, without exchanges of culture or assay medium, or transfer of cells or cell supernatant. The method uses freshly prepared reagents and does not rely on a proprietary, commercially supplied kit. Following experimental treatment, calcein acetoxymethyl ester (CaAM) is added to each well of cultured cells; after 30 min, the fluorescence intensity (emission λmax ∼ 530 nm) is measured. The signal is due to formation of calcein, which is produced from CaAM by action of esterase activity found in intact live cells. Since live cells may express plasma membrane multidrug transport proteins, especially of the ABC transporter family, the CaAM incubation is carried out in the presence of an inhibitor of this efflux process, thereby improving the dynamic range of the assay. Next, SYTOX® Orange (SO) is added to the culture wells, and, after a 30-min incubation, fluorescence intensity (emission λmax ∼ 590 nm) is measured again. SO is excluded from cells that have an intact plasma membrane, but penetrates dead/dying cells and can diffuse into the nucleus, where it binds to and forms a fluorescent complex with DNA. The CaAM already added to the wells causes no interference with the latter fluorescent signal. At the conclusion of the duplex assay, both live and dead cells remain in the culture wells and can be documented by digital imaging to demonstrate correlation of cellular morphology with the assay output. Two examples of the application of this method are provided, using cytotoxic compounds having different mechanisms of action.
Collapse
|
31
|
Prabhu AV, Luu W, Li D, Sharpe LJ, Brown AJ. DHCR7: A vital enzyme switch between cholesterol and vitamin D production. Prog Lipid Res 2016; 64:138-151. [PMID: 27697512 DOI: 10.1016/j.plipres.2016.09.003] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 09/29/2016] [Accepted: 09/29/2016] [Indexed: 01/07/2023]
Abstract
The conversion of 7-dehydrocholesterol to cholesterol, the final step of cholesterol synthesis in the Kandutsch-Russell pathway, is catalyzed by the enzyme 7-dehydrocholesterol reductase (DHCR7). Homozygous or compound heterozygous mutations in DHCR7 lead to the developmental disease Smith-Lemli-Opitz syndrome, which can also result in fetal mortality, highlighting the importance of this enzyme in human development and survival. Besides serving as a substrate for DHCR7, 7-dehydrocholesterol is also a precursor of vitamin D via the action of ultraviolet light on the skin. Thus, DHCR7 exerts complex biological effects, involved in both cholesterol and vitamin D production. Indeed, we argue that DHCR7 can act as a switch between cholesterol and vitamin D synthesis. This review summarizes current knowledge about the critical enzyme DHCR7, highlighting recent findings regarding its structure, transcriptional and post-transcriptional regulation, and its links to vitamin D synthesis. Greater understanding about DHCR7 function, regulation and its place within cellular metabolism will provide important insights into its biological roles.
Collapse
Affiliation(s)
- Anika V Prabhu
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Winnie Luu
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Dianfan Li
- National Center for Protein Sciences, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Laura J Sharpe
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia
| | - Andrew J Brown
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, Australia.
| |
Collapse
|