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Ritter K, Somnuke P, Hu L, Griemert EV, Schäfer MKE. Current state of neuroprotective therapy using antibiotics in human traumatic brain injury and animal models. BMC Neurosci 2024; 25:10. [PMID: 38424488 PMCID: PMC10905838 DOI: 10.1186/s12868-024-00851-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 02/02/2024] [Indexed: 03/02/2024] Open
Abstract
TBI is a leading cause of death and disability in young people and older adults worldwide. There is no gold standard treatment for TBI besides surgical interventions and symptomatic relief. Post-injury infections, such as lower respiratory tract and surgical site infections or meningitis are frequent complications following TBI. Whether the use of preventive and/or symptomatic antibiotic therapy improves patient mortality and outcome is an ongoing matter of debate. In contrast, results from animal models of TBI suggest translational perspectives and support the hypothesis that antibiotics, independent of their anti-microbial activity, alleviate secondary injury and improve neurological outcomes. These beneficial effects were largely attributed to the inhibition of neuroinflammation and neuronal cell death. In this review, we briefly outline current treatment options, including antibiotic therapy, for patients with TBI. We then summarize the therapeutic effects of the most commonly tested antibiotics in TBI animal models, highlight studies identifying molecular targets of antibiotics, and discuss similarities and differences in their mechanistic modes of action.
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Affiliation(s)
- Katharina Ritter
- Department of Anesthesiology, University Medical Center, Johannes Gutenberg-University Mainz, Langenbeckstraße 1 (Bld. 505), Mainz, 55131, Germany
| | - Pawit Somnuke
- Department of Anesthesiology, University Medical Center, Johannes Gutenberg-University Mainz, Langenbeckstraße 1 (Bld. 505), Mainz, 55131, Germany
- Department of Anesthesiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Lingjiao Hu
- Department of Anesthesiology, University Medical Center, Johannes Gutenberg-University Mainz, Langenbeckstraße 1 (Bld. 505), Mainz, 55131, Germany
- Department of Gastroenterology, Nanxishan Hospital of Guangxi Zhuang Autonomous Region, Guilin, China
| | - Eva-Verena Griemert
- Department of Anesthesiology, University Medical Center, Johannes Gutenberg-University Mainz, Langenbeckstraße 1 (Bld. 505), Mainz, 55131, Germany
| | - Michael K E Schäfer
- Department of Anesthesiology, University Medical Center, Johannes Gutenberg-University Mainz, Langenbeckstraße 1 (Bld. 505), Mainz, 55131, Germany.
- Focus Program Translational Neurosciences (FTN, Johannes Gutenberg-University Mainz, Mainz, Germany.
- Research Center for Immunotherapy, University Medical Center, Johannes Gutenberg- University Mainz, Mainz, Germany.
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Ye Y, Tong HYK, Chong WH, Li Z, Tam PKH, Baptista-Hon DT, Monteiro O. A systematic review and meta-analysis of the effects of long-term antibiotic use on cognitive outcomes. Sci Rep 2024; 14:4026. [PMID: 38369574 PMCID: PMC10874946 DOI: 10.1038/s41598-024-54553-4] [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: 11/10/2023] [Accepted: 02/14/2024] [Indexed: 02/20/2024] Open
Abstract
Antibiotics are indispensable to infection management. However, use of antibiotics can cause gut microbiota dysbiosis, which has been linked to cognitive impairment by disrupting communication between the gut microbiota and the brain. We conducted a systematic review and meta-analysis on the effects of long-term antibiotic use on cognitive outcomes. We have searched PubMed, Web of Science, Embase, Cochrane Library and Scopus for English publications before March 2023 following the PRISMA guidelines. Screening, data extraction, and quality assessment were performed in duplicate. 960 articles were screened and 16 studies which evaluated the effect of any antibiotic compared to no antibiotics or placebo were included. Case-reports, in vitro and animal studies were excluded. We found that antibiotic use was associated with worse cognitive outcomes with a pooled effect estimate of - 0.11 (95% CI - 0.15, - 0.07, Z = 5.45; P < 0.00001). Subgroup analyses performed on adult vs pediatric patients showed a similar association of antibiotic on cognition in both subgroups. Antibiotic treatment was not associated with worse cognition on subjects with existing cognitive impairment. On the other hand, antibiotic treatment on subjects with no prior cognitive impairment was associated with worse cognitive performance later in life. This calls for future well-designed and well-powered studies to investigate the impact of antibiotics on cognitive performance.
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Affiliation(s)
- Yongqin Ye
- Faculty of Medicine, Medical Sciences Division, Macau University of Science and Technology, Avenida da Harmonia, Praia Park, Coloane, 999078, Macao SAR, China
| | | | - Wai Hong Chong
- Faculty of Medicine, Medical Sciences Division, Macau University of Science and Technology, Avenida da Harmonia, Praia Park, Coloane, 999078, Macao SAR, China
| | - Zhiqian Li
- Faculty of Medicine, Medical Sciences Division, Macau University of Science and Technology, Avenida da Harmonia, Praia Park, Coloane, 999078, Macao SAR, China
| | - Paul Kwong Hang Tam
- Faculty of Medicine, Medical Sciences Division, Macau University of Science and Technology, Avenida da Harmonia, Praia Park, Coloane, 999078, Macao SAR, China
| | - Daniel T Baptista-Hon
- Faculty of Medicine, Medical Sciences Division, Macau University of Science and Technology, Avenida da Harmonia, Praia Park, Coloane, 999078, Macao SAR, China
- Division of Systems Medicine, School of Medicine, University of Dundee, Dundee, UK
| | - Olivia Monteiro
- Faculty of Medicine, Medical Sciences Division, Macau University of Science and Technology, Avenida da Harmonia, Praia Park, Coloane, 999078, Macao SAR, China.
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Cores Á, Carmona-Zafra N, Clerigué J, Villacampa M, Menéndez JC. Quinones as Neuroprotective Agents. Antioxidants (Basel) 2023; 12:1464. [PMID: 37508002 PMCID: PMC10376830 DOI: 10.3390/antiox12071464] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 07/12/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Quinones can in principle be viewed as a double-edged sword in the treatment of neurodegenerative diseases, since they are often cytoprotective but can also be cytotoxic due to covalent and redox modification of biomolecules. Nevertheless, low doses of moderately electrophilic quinones are generally cytoprotective, mainly due to their ability to activate the Keap1/Nrf2 pathway and thus induce the expression of detoxifying enzymes. Some natural quinones have relevant roles in important physiological processes. One of them is coenzyme Q10, which takes part in the oxidative phosphorylation processes involved in cell energy production, as a proton and electron carrier in the mitochondrial respiratory chain, and shows neuroprotective effects relevant to Alzheimer's and Parkinson's diseases. Additional neuroprotective quinones that can be regarded as coenzyme Q10 analogues are idobenone, mitoquinone and plastoquinone. Other endogenous quinones with neuroprotective activities include tocopherol-derived quinones, most notably vatiquinone, and vitamin K. A final group of non-endogenous quinones with neuroprotective activity is discussed, comprising embelin, APX-3330, cannabinoid-derived quinones, asterriquinones and other indolylquinones, pyrroloquinolinequinone and its analogues, geldanamycin and its analogues, rifampicin quinone, memoquin and a number of hybrid structures combining quinones with amino acids, cholinesterase inhibitors and non-steroidal anti-inflammatory drugs.
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Affiliation(s)
- Ángel Cores
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain
| | - Noelia Carmona-Zafra
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain
| | - José Clerigué
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain
| | - Mercedes Villacampa
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain
| | - J Carlos Menéndez
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, Plaza de Ramón y Cajal sn, 28040 Madrid, Spain
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Singh S, Navale GR, Agrawal S, Singh HK, Singla L, Sarkar D, Sarma M, Choudhury AR, Ghosh K. Design and synthesis of ruthenium complexes and their studies on the inhibition of amyloid β (1-42) peptide aggregation. Int J Biol Macromol 2023; 239:124197. [PMID: 36972817 DOI: 10.1016/j.ijbiomac.2023.124197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 03/07/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023]
Abstract
Misfolding and protein aggregation have been linked to numerous human neurodegenerative disorders such as Alzheimer's, prions, and Parkinson's. Due to their interesting photophysical properties, ruthenium (Ru) complexes have received considerable attention in studying protein aggregation. In this study, we synthesized the novel Ru complexes ([Ru(p-cymene)Cl(L-1)][PF6](Ru-1), and [Ru(p-cymene)Cl(L-2)][PF6](Ru-2)) and investigated their inhibitory activity against the bovine serum albumin (BSA) aggregation and the Aβ1-42 peptides amyloid formation. Several spectroscopic methods were used to characterize the complexes, and the molecular structure was determined by X-ray crystallography. Amyloid aggregation and inhibition activity were examined using the Thioflavin-T (ThT) assay, and secondary structures were analyzed by circular dichroism (CD) spectroscopy and transmission electron microscopy (TEM). The cell viability assay was carried out on the neuroblastoma cell line, revealing that the Ru-2 complex showed better protective effects against Aβ1-42 peptide toxicity on neuro-2a cells than the Ru-1 complex. Molecular docking studies elucidate binding sites and interactions between the Ru-complexes and the Aβ1-42 fibrils. The experimental studies revealed that these complexes significantly inhibited BSA aggregation and Aβ1-42 amyloid fibril formation at 1:3 and 1:1 equimolar concentrations, respectively. Antioxidant assays demonstrated that these complexes act as antioxidants, protecting from amyloid-induced oxidative stress. Molecular docking studies with the monomeric Aβ1-42 (PDB: 1IYT) show hydrophobic interaction, and both complexes bind preferably in the central region of the peptide and coordinate with two binding sites of the peptide. Hence, we suggest that the Ru-based complexes could be applied as a potential agent in metallopharmaceutical research against Alzheimer's disease.
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Affiliation(s)
- Sain Singh
- Department of Chemistry, Indian Institute of Technology, Roorkee 247667, India
| | - Govinda R Navale
- Department of Chemistry, Indian Institute of Technology, Roorkee 247667, India
| | - Sonia Agrawal
- Department of Organic Chemistry, CSIR-National Chemical Laboratory, Pune 411 008, India
| | - Haobam Kisan Singh
- Department of Chemistry, Indian Institute of Technology, Guwahati 781039, India
| | - Labhini Singla
- Department of Chemical Sciences, Indian Institute of Science Education and Research, Mohali, India
| | - Dhiman Sarkar
- Department of Organic Chemistry, CSIR-National Chemical Laboratory, Pune 411 008, India
| | - Manabendra Sarma
- Department of Chemistry, Indian Institute of Technology, Guwahati 781039, India
| | - Anghuman Roy Choudhury
- Department of Chemical Sciences, Indian Institute of Science Education and Research, Mohali, India
| | - Kaushik Ghosh
- Department of Chemistry, Indian Institute of Technology, Roorkee 247667, India; Department of Biosciences and Bioengineering, Indian Institute of Technology, Roorkee 247667, India.
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Ding M, Niu H, Guan P, Hu X. Molecularly imprinted sensor based on poly-o-phenylenediamine-hydroquinone polymer for β-amyloid-42 detection. Anal Bioanal Chem 2023; 415:1545-1557. [PMID: 36808273 DOI: 10.1007/s00216-023-04552-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/30/2022] [Accepted: 01/17/2023] [Indexed: 02/21/2023]
Abstract
A sensitive and selective molecularly imprinted polymer (MIP) sensor was developed for the determination of amyloid-β (1-42) (Aβ42). The glassy carbon electrode (GCE) was successively modified with electrochemical reduction graphene oxide (ERG) and poly(thionine-methylene blue) (PTH-MB). The MIPs were synthesized by electropolymerization with Aβ42 as a template and o-phenylenediamine (o-PD) and hydroquinone (HQ) as functional monomers. Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), chronoamperometry (CC), and differential pulse voltammetry (DPV) were used to study the preparation process of the MIP sensor. The preparation conditions of the sensor were investigated in detail. In optimal experimental conditions, the response current of the sensor was linear in the range of 0.12-10 μg mL-1 with a detection limit of 0.018 ng mL-1. The MIP-based sensor successfully detected Aβ42 in commercial fetal bovine serum (cFBS) and artificial cerebrospinal fluid (aCSF).
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Affiliation(s)
- Minling Ding
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
| | - Huizhe Niu
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China
| | - Ping Guan
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China.
| | - Xiaoling Hu
- School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, Xi'an, 710072, People's Republic of China.
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Subramanian A, Tamilanban T, Alsayari A, Ramachawolran G, Wong LS, Sekar M, Gan SH, Subramaniyan V, Chinni SV, Izzati Mat Rani NN, Suryadevara N, Wahab S. Trilateral association of autophagy, mTOR and Alzheimer's disease: Potential pathway in the development for Alzheimer's disease therapy. Front Pharmacol 2022; 13:1094351. [PMID: 36618946 PMCID: PMC9817151 DOI: 10.3389/fphar.2022.1094351] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
The primary and considerable weakening event affecting elderly individuals is age-dependent cognitive decline and dementia. Alzheimer's disease (AD) is the chief cause of progressive dementia, and it is characterized by irreparable loss of cognitive abilities, forming senile plaques having Amyloid Beta (Aβ) aggregates and neurofibrillary tangles with considerable amounts of tau in affected hippocampus and cortex regions of human brains. AD affects millions of people worldwide, and the count is showing an increasing trend. Therefore, it is crucial to understand the underlying mechanisms at molecular levels to generate novel insights into the pathogenesis of AD and other cognitive deficits. A growing body of evidence elicits the regulatory relationship between the mammalian target of rapamycin (mTOR) signaling pathway and AD. In addition, the role of autophagy, a systematic degradation, and recycling of cellular components like accumulated proteins and damaged organelles in AD, is also pivotal. The present review describes different mechanisms and signaling regulations highlighting the trilateral association of autophagy, the mTOR pathway, and AD with a description of inhibiting drugs/molecules of mTOR, a strategic target in AD. Downregulation of mTOR signaling triggers autophagy activation, degrading the misfolded proteins and preventing the further accumulation of misfolded proteins that inhibit the progression of AD. Other target mechanisms such as autophagosome maturation, and autophagy-lysosomal pathway, may initiate a faulty autophagy process resulting in senile plaques due to defective lysosomal acidification and alteration in lysosomal pH. Hence, the strong link between mTOR and autophagy can be explored further as a potential mechanism for AD therapy.
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Affiliation(s)
- Arunkumar Subramanian
- Department of Pharmacology, SRM College of Pharmacy, SRM Institute of Science and Technology, Chengalpattu, Tamilnadu, India
| | - T. Tamilanban
- Department of Pharmacology, SRM College of Pharmacy, SRM Institute of Science and Technology, Chengalpattu, Tamilnadu, India,*Correspondence: T. Tamilanban, ; Gobinath Ramachawolran, ; Ling Shing Wong, ; Mahendran Sekar,
| | - Abdulrhman Alsayari
- Department of Pharmacognosy, College of Pharmacy, King Khalid University, Abha, Saudi Arabia,Complementary and Alternative Medicine Unit, King Khalid University, Abha, Saudi Arabia
| | - Gobinath Ramachawolran
- Department of Foundation, RCSI & UCD Malaysia Campus, Georgetown, Pulau Pinang, Malaysia,*Correspondence: T. Tamilanban, ; Gobinath Ramachawolran, ; Ling Shing Wong, ; Mahendran Sekar,
| | - Ling Shing Wong
- Faculty of Health and Life Sciences, INTI International University, Nilai, Malaysia,*Correspondence: T. Tamilanban, ; Gobinath Ramachawolran, ; Ling Shing Wong, ; Mahendran Sekar,
| | - Mahendran Sekar
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy and Health Sciences, Royal College of Medicine Perak, Universiti Kuala Lumpur, Ipoh, Perak, Malaysia,*Correspondence: T. Tamilanban, ; Gobinath Ramachawolran, ; Ling Shing Wong, ; Mahendran Sekar,
| | - Siew Hua Gan
- School of Pharmacy, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - Vetriselvan Subramaniyan
- Faculty of Medicine, Bioscience and Nursing, MAHSA University, Bandar Saujana Putra, Selangor, Malaysia
| | - Suresh V. Chinni
- Department of Biochemistry, Faculty of Medicine, Bioscience, and Nursing, MAHSA University, Bandar Saujana Putra, Selangor, Malaysia,Department of Periodontics, Saveetha Dental College and Hospitals, Saveetha Institute of Medical and Technical Sciences, Chennai, India
| | - Nur Najihah Izzati Mat Rani
- Faculty of Pharmacy and Health Sciences, Royal College of Medicine Perak, Universiti Kuala Lumpur, Ipoh, Perak, Malaysia
| | - Nagaraja Suryadevara
- Faculty of Medicine, Bioscience and Nursing, MAHSA University, Bandar Saujana Putra, Selangor, Malaysia
| | - Shadma Wahab
- Department of Pharmacognosy, College of Pharmacy, King Khalid University, Abha, Saudi Arabia,Complementary and Alternative Medicine Unit, King Khalid University, Abha, Saudi Arabia
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Kakoti BB, Bezbaruah R, Ahmed N. Therapeutic drug repositioning with special emphasis on neurodegenerative diseases: Threats and issues. Front Pharmacol 2022; 13:1007315. [PMID: 36263141 PMCID: PMC9574100 DOI: 10.3389/fphar.2022.1007315] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 09/12/2022] [Indexed: 11/21/2022] Open
Abstract
Drug repositioning or repurposing is the process of discovering leading-edge indications for authorized or declined/abandoned molecules for use in different diseases. This approach revitalizes the traditional drug discovery method by revealing new therapeutic applications for existing drugs. There are numerous studies available that highlight the triumph of several drugs as repurposed therapeutics. For example, sildenafil to aspirin, thalidomide to adalimumab, and so on. Millions of people worldwide are affected by neurodegenerative diseases. According to a 2021 report, the Alzheimer's disease Association estimates that 6.2 million Americans are detected with Alzheimer's disease. By 2030, approximately 1.2 million people in the United States possibly acquire Parkinson's disease. Drugs that act on a single molecular target benefit people suffering from neurodegenerative diseases. Current pharmacological approaches, on the other hand, are constrained in their capacity to unquestionably alter the course of the disease and provide patients with inadequate and momentary benefits. Drug repositioning-based approaches appear to be very pertinent, expense- and time-reducing strategies for the enhancement of medicinal opportunities for such diseases in the current era. Kinase inhibitors, for example, which were developed for various oncology indications, demonstrated significant neuroprotective effects in neurodegenerative diseases. This review expounds on the classical and recent examples of drug repositioning at various stages of drug development, with a special focus on neurodegenerative disorders and the aspects of threats and issues viz. the regulatory, scientific, and economic aspects.
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Affiliation(s)
- Bibhuti Bhusan Kakoti
- Department of Pharmaceutical Sciences, Faculty of Science and Engineering, Dibrugarh University, Dibrugarh, India
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Vezenkov LT, Danalev DL, Iwanov I, Lozanov V, Atanasov A, Todorova R, Vassilev N, Karadjova V. Synthesis and biological study of new galanthamine-peptide derivatives designed for prevention and treatment of Alzheimer 's disease. Amino Acids 2022; 54:897-910. [PMID: 35562605 DOI: 10.1007/s00726-022-03167-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 04/23/2022] [Indexed: 11/29/2022]
Abstract
The Alzheimer's disease leads to neurodegenerative processes and affecting negatively million people worldwide. The treatment of the disease is still difficult and incomplete in practice. Galanthamine is one of the most commonly used drugs against the illness. The main aim of this work is design and synthesis of new derivatives of galanthamine comprising peptide moiety as well as study of their β-secretase inhibitory activity and the anti-aggregating effect. All new derivatives of galanthamine containing analogues of Leu-Val-Phe-Phe (Aβ17-Aβ20) were synthesized in solution using fragment and consecutive condensation approaches. The new derivatives were characterized by melting points, NMR, and HPLC/MS. They were tested in vitro for β-secretase inhibition activity by means of fluorescent method and were investigated in vitro for anti-aggregation activity on sheep platelet-rich plasma. Although the new compounds do not contain a structural element responsible for the β-secretase inhibition, five of them show high or good β-secretase inhibitory activity between 19.98 and 51.19% with IC50 between 1.95 and 5.26 nM. Four of the new molecules were able to inhibit platelet aggregation between 55.0 and 90.0% with IC50 between 0.69 and 1.36 µM. Four of the compounds were able to inhibit platelet aggregation and two of them have high anti-aggregating effects.
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Affiliation(s)
| | - Dancho L Danalev
- University of Chemical Technology and Metallurgy, Sofia, 1756, Bulgaria.
| | - Iwan Iwanov
- University of Chemical Technology and Metallurgy, Sofia, 1756, Bulgaria
| | - Valentin Lozanov
- Department of Medical Chemistry and Biochemistry, Medical University of Sofia, Sofia, 1000, Bulgaria
| | - Atanas Atanasov
- Medical Faculty, Trakia University, Stara Zagora, 6000, Bulgaria
| | - Rumyana Todorova
- Medical Faculty, Trakia University, Stara Zagora, 6000, Bulgaria
| | - Nikolay Vassilev
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, Sofia, 1113, Bulgaria
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Sekino N, Selim M, Shehadah A. Sepsis-associated brain injury: underlying mechanisms and potential therapeutic strategies for acute and long-term cognitive impairments. J Neuroinflammation 2022; 19:101. [PMID: 35488237 PMCID: PMC9051822 DOI: 10.1186/s12974-022-02464-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 04/14/2022] [Indexed: 12/29/2022] Open
Abstract
Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis causes cerebral dysfunction in the short and long term and induces disruption of the blood–brain barrier (BBB), neuroinflammation, hypoperfusion, and accumulation of amyloid β (Aβ) and tau protein in the brain. White matter changes and brain atrophy can be detected using brain imaging, but unfortunately, there is no specific treatment that directly addresses the underlying mechanisms of cognitive impairments in sepsis. Here, we review the underlying mechanisms of sepsis-associated brain injury, with a focus on BBB dysfunction and Aβ and tau protein accumulation in the brain. We also describe the neurological manifestations and imaging findings of sepsis-associated brain injury, and finally, we propose potential therapeutic strategies for acute and long-term cognitive impairments associated with sepsis. In the acute phase of sepsis, we suggest using antibiotics (such as rifampicin), targeting proinflammatory cytokines, and preventing ischemic injuries and hypoperfusion. In the late phase of sepsis, we suggest targeting neuroinflammation, BBB dysfunction, Aβ and tau protein phosphorylation, glycogen synthase kinase-3 beta (GSK3β), and the receptor for advanced glycation end products (RAGE). These proposed strategies are meant to bring new mechanism-based directions for future basic and clinical research aimed at preventing or ameliorating acute and long-term cognitive impairments in patients with sepsis.
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Affiliation(s)
- Nobufumi Sekino
- Department of Medicine, Translational Therapeutics Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Magdy Selim
- Department of Neurology, Stroke and Cerebrovascular Diseases Division, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS-641, Boston, MA, 02215, USA
| | - Amjad Shehadah
- Department of Neurology, Stroke and Cerebrovascular Diseases Division, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS-641, Boston, MA, 02215, USA.
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Pang Y, Lin W, Zhan L, Zhang J, Zhang S, Jin H, Zhang H, Wang X, Li X. Inhibiting Autophagy Pathway of PI3K/AKT/mTOR Promotes Apoptosis in SK-N-SH Cell Model of Alzheimer's Disease. JOURNAL OF HEALTHCARE ENGINEERING 2022; 2022:6069682. [PMID: 35178230 PMCID: PMC8846974 DOI: 10.1155/2022/6069682] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/22/2021] [Accepted: 12/31/2021] [Indexed: 01/31/2023]
Abstract
Alzheimer's disease is the most common dementia disease characterized by chronic progressive neurodegeneration. The incidence of Alzheimer's disease is on the rise as the population ages at an accelerating pace. According to epidemiological data, by 2050, the number of Alzheimer's patients in the United States will be three times higher than that in 2010, and a similar trend is occurring in China. To explore the effect and mechanism of let-7b by detecting the expression level of let-7b in Alzheimer's disease, fifty patients with Alzheimer's disease and thirty healthy controls were selected. The expression levels of let-7 families (let-7a, let-7b, let-7c, let-7d, let-7e, let-7f, let-7g, and let-7i) were detected by qPCR. Human neuroblastoma cell SK-N-SH were divided into control group (untreated), model group (treated with Aβ1-40), Aβ1-40+let-7b mimic group (treated with Aβ1-40 and transfected with let-7b mimic), and Aβ1-40+miR-NC group (treated with aβ1-40 and transfected with miR-NC). let-7b expression and cell survival rate were detected by qPCR and CCK-8, and the levels of caspase 3, LC3, beclin-1, PI3K, p-AKT, and p-mTOR were detected by Western blot. let-7b was significantly different between the case group and the control group (p < 0.001). CCK-8 showed a significant decrease in cell viability in Aβ1-40 treatment group compared with that in the control group (p < 0.01). Overexpression of let-7b significantly reduced the survival rate of the cells, and the expression of LC3II/LC3I and beclin-1 in the cells was significantly reduced by aβ1-40 treatment (p < 0.001). let-7b overexpression also inhibited autophagy via reducing the level of LC3II/LC3I and beclin-1 (p < 0.001). Aβ1-40 treatment and let-7b overexpression promoted apoptosis by increasing the expression of cleavage caspase 3. Western blot indicated that Aβ1-40 treatment and let-7b overexpression could increase the expression of PI3K, p-AKT, and p-mTOR. let-7b overexpression could inhibit autophagy and promote apoptosis in Alzheimer's cells by promoting PI3K/AKT/mTOR signaling pathway. PI3K/AKT/mTOR signaling pathway is involved in the imbalance between autophagy and apoptosis.
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Affiliation(s)
- Yu Pang
- Department of Neurology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar 161000, China
| | - Wennan Lin
- General Department, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar 161000, China
| | - Lan Zhan
- Department of Neurology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar 161000, China
| | - Jiawen Zhang
- Department of Neurology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar 161000, China
| | - Shicun Zhang
- Department of Neurology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar 161000, China
| | - Hongwei Jin
- Department of Neurology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar 161000, China
| | - He Zhang
- Department of Neurology, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar 161000, China
| | - Xiaoli Wang
- School of Pharmacy, Qiqihar Medical University, Qiqihar 161000, China
| | - Xiaoming Li
- The Institute of Medicine, Qiqihar Medical University, Qiqihar 161000, China
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11
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Umeda T, Sakai A, Shigemori K, Yokota A, Kumagai T, Tomiyama T. Oligomer-Targeting Prevention of Neurodegenerative Dementia by Intranasal Rifampicin and Resveratrol Combination - A Preclinical Study in Model Mice. Front Neurosci 2021; 15:763476. [PMID: 34966254 PMCID: PMC8710719 DOI: 10.3389/fnins.2021.763476] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/23/2021] [Indexed: 12/15/2022] Open
Abstract
Amyloidogenic protein oligomers are thought to play an important role in the pathogenesis of neurodegenerative dementia, including Alzheimer’s disease, frontotemporal dementia, and dementia with Lewy bodies. Previously we demonstrated that oral or intranasal rifampicin improved the cognition of APP-, tau-, and α-synuclein-transgenic mice by reducing the amount of Aβ, tau, and α-synuclein oligomers in the brain. In the present study, to explore more effective and safer medications for dementia, we tested the drug combination of rifampicin and resveratrol, which is a multifunctional natural polyphenol with the potential to antagonize the adverse effects of rifampicin. The mixture was intranasally administered to APP-, tau-, and α-synuclein-transgenic mice, and their memory and oligomer-related pathologies were evaluated. Compared with rifampicin and resveratrol alone, the combinatorial medicine significantly improved mouse cognition, reduced amyloid oligomer accumulation, and recovered synaptophysin levels in the hippocampus. The plasma levels of liver enzymes, which reflect hepatic injury and normally increase by rifampicin treatment, remained normal by the combination treatment. Notably, resveratrol alone and the combinatorial medicine, but not rifampicin alone, enhanced the levels of brain-derived neurotrophic factor (BDNF) and its precursor, pro-BDNF, in the hippocampus. Furthermore, the combination showed a synergistic effect in ameliorating mouse cognition. These results show the advantages of this combinatorial medicine with regards to safety and effectiveness over single-drug rifampicin. Our findings may provide a feasible means for the prevention of neurodegenerative dementia that targets toxic oligomers.
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Affiliation(s)
- Tomohiro Umeda
- Department of Translational Neuroscience, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Ayumi Sakai
- Department of Translational Neuroscience, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Keiko Shigemori
- Department of Translational Neuroscience, Osaka City University Graduate School of Medicine, Osaka, Japan
| | - Ayumi Yokota
- Department of Translational Neuroscience, Osaka City University Graduate School of Medicine, Osaka, Japan
| | | | - Takami Tomiyama
- Department of Translational Neuroscience, Osaka City University Graduate School of Medicine, Osaka, Japan.,Medilabo RFP, Inc., Kyoto, Japan
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12
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Khan AN, Qureshi IA, Khan UK, Uversky VN, Khan RH. Inhibition and disruption of amyloid formation by the antibiotic levofloxacin: A new direction for antibiotics in an era of multi-drug resistance. Arch Biochem Biophys 2021; 714:109077. [PMID: 34728171 DOI: 10.1016/j.abb.2021.109077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/16/2021] [Accepted: 10/29/2021] [Indexed: 12/24/2022]
Abstract
Neurodegenerative diseases are a group of debilitating maladies involving protein aggregation. To this day, all advances in neurodegenerative disease therapeutics have helped symptomatically but have not prevented the root cause of the disease, i.e., the aggregation of involved proteins. Antibiotics are becoming increasingly obsolete due to the rising multidrug resistance strains of bacteria. Thus, antibiotics, if put to different use as therapeutics against other diseases, could pave a new direction to the world of antibiotics. Hence, we studied the antibiotic levofloxacin for its potential anti-amyloidogenic behavior using human lysozyme, a protein involved in non-systemic amyloidosis, as a model system. At the sub-stoichiometric level, levofloxacin was able to inhibit amyloid formation in human lysozyme as observed by various spectroscopic and microscopic methods, with IC50 values as low as 8.8 ± 0.1 μM. Levofloxacin also displayed a retarding effect on seeding phenomena by elongating the lag-phase (from 0 to 88 h) at lower concentration, and arresting lysozyme fibrillation at the lag stage in sub-stoichiometric concentrations. Structural and computational analyses provided mechanistic insight showing that levofloxacin stabilizes the lysozyme in the native state by binding to the aggregation-prone residues, and thereby inhibiting amyloid fibrillation. Levofloxacin also showed the property of disrupting amyloid fibrils into a smaller polymeric form of proteins which were less cytotoxic as confirmed by hemolytic assay. Therefore, we throw new light on levofloxacin as an amyloid inhibitor and disruptor which could pave way to utilization of levofloxacin as a potential therapeutic against non-systemic amyloidosis and neurodegenerative diseases.
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Affiliation(s)
- Asra Nasir Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
| | - Insaf Ahmed Qureshi
- Department of Biotechnology & Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, 500046, India
| | - Umar Khalid Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Rizwan Hasan Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, 202002, India.
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13
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Kaya-Tilki E, Dikmen M. Neuroprotective effects of some epigenetic modifying drugs' on Chlamydia pneumoniae-induced neuroinflammation: A novel model. PLoS One 2021; 16:e0260633. [PMID: 34847172 PMCID: PMC8631675 DOI: 10.1371/journal.pone.0260633] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 11/14/2021] [Indexed: 12/02/2022] Open
Abstract
Chlamydia pneumoniae (Cpn) is a gram-negative intracellular pathogen that causes a variety of pulmonary diseases, and there is growing evidence that it may play a role in Alzheimer's disease (AD) pathogenesis. Cpn can interact functionally with host histones, altering the host's epigenetic regulatory system by introducing bacterial products into the host tissue and inducing a persistent inflammatory response. Because Cpn is difficult to propagate, isolate, and detect, a modified LPS-like neuroinflammation model was established using lyophilized cell free supernatant (CFS) obtained from infected cell cultures, and the effects of CFS were compared to LPS. The neuroprotective effects of Trichostatin A (TSA), givinostat, and RG108, which are effective on epigenetic mechanisms, and the antibiotic rifampin, were studied in this newly introduced model and in the presence of amyloid beta (Aβ) 1-42. The neuroprotective effects of the drugs, as well as the effects of CFS and LPS, were evaluated in Aβ-induced neurotoxicity using a real-time cell analysis system, total ROS, and apoptotic impact. TSA, RG108, givinostat, and rifampin all demonstrated neuroprotective effects in both this novel model and Aβ-induced neurotoxicity. The findings are expected to provide early evidence on neuroprotective actions against Cpn-induced neuroinflammation and Aβ-induced neurotoxicity, which could represent a new treatment option for AD, for which there are currently few treatment options.
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Affiliation(s)
- Elif Kaya-Tilki
- Department of Pharmacology, Faculty of Pharmacy, Anadolu University, Eskisehir, Turkey
| | - Miriş Dikmen
- Department of Pharmacology, Faculty of Pharmacy, Anadolu University, Eskisehir, Turkey
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14
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Shen S, Zhang C, Xu YM, Shi CH. The Role of Pathogens and Anti-Infective Agents in Parkinson's Disease, from Etiology to Therapeutic Implications. JOURNAL OF PARKINSONS DISEASE 2021; 12:27-44. [PMID: 34719435 PMCID: PMC8842782 DOI: 10.3233/jpd-212929] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Parkinson's disease is a debilitating neurodegenerative disorder whose etiology is still unclear, hampering the development of effective treatments. There is an urgent need to identify the etiology and provide further effective treatments. Recently, accumulating evidence has indicated that infection may play a role in the etiology of Parkinson's disease. The infective pathogens may act as a trigger for Parkinson's disease, the most common of which are hepatitis C virus, influenza virus, and Helicobacter pylori. In addition, gut microbiota is increasingly recognized to influence brain function through the gut-brain axis, showing an important role in the pathogenesis of Parkinson's disease. Furthermore, a series of anti-infective agents exhibit surprising neuroprotective effects via various mechanisms, such as interfering with α-synuclein aggregation, inhibiting neuroinflammation, attenuating oxidative stress, and preventing from cell death, independent of their antimicrobial effects. The pleiotropic agents affect important events in the pathogenesis of Parkinson's disease. Moreover, most of them are less toxic, clinically safe and have good blood-brain penetrability, making them hopeful candidates for the treatment of Parkinson's disease. However, the use of antibiotics and subsequent gut dysbiosis may also play a role in Parkinson's disease, making the long-term effects of anti-infective drugs worthy of further consideration and exploration. This review summarizes the current evidence for the association between infective pathogens and Parkinson's disease and subsequently explores the application prospects of anti-infective drugs in Parkinson's disease treatment, providing novel insights into the pathogenesis and treatment of Parkinson's disease.
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Affiliation(s)
- Si Shen
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Chan Zhang
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China
| | - Yu-Ming Xu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Institute of Neuroscience, Zhengzhou University, Zhengzhou, Henan, China
| | - Chang-He Shi
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Henan Key Laboratory of Cerebrovascular Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, Henan, China.,Institute of Neuroscience, Zhengzhou University, Zhengzhou, Henan, China
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15
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Zhu L, Yuan Q, Zeng Z, Zhou R, Luo R, Zhang J, Tsang CK, Bi W. Rifampicin Suppresses Amyloid-β Accumulation Through Enhancing Autophagy in the Hippocampus of a Lipopolysaccharide-Induced Mouse Model of Cognitive Decline. J Alzheimers Dis 2021; 79:1171-1184. [PMID: 33386800 DOI: 10.3233/jad-200690] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Alzheimer's disease (AD) is characterized by amyloid-β (Aβ) deposition. The metabolism of Aβ is critically affected by autophagy. Although rifampicin is known to mediate neuroinflammation, the underlying mechanism by which rifampicin regulates the cognitive sequelae remains unknown. OBJECTIVE Based on our previous findings that rifampicin possesses neuroprotective effects on improving cognitive function after neuroinflammation, we aimed to examine in this study whether rifampicin can inhibit Aβ accumulation by enhancing autophagy in a mouse model of lipopolysaccharide (LPS)-induced cognitive impairment. METHODS Adult C57BL/6 mice were intraperitoneally injected with rifampicin, chloroquine, and/or LPS every day for 7 days. Pathological and biochemical assays and behavioral tests were performed to determine the therapeutic effect and mechanism of rifampicin on the hippocampus of LPS-induced mice. RESULTS We found that rifampicin ameliorated cognitive impairments in the LPS-induced mice. In addition, rifampicin attenuated the inhibition of autophagosome formation, suppressed the accumulation of Aβ1-42, and protected the hippocampal neurons against LPS-induced damage. Our results further demonstrated that rifampicin improved the neurological function by promoting autophagy through the inhibition of Akt/mTOR/p70S6K signaling pathway in the hippocampus of LPS-induced mice. CONCLUSION Rifampicin ameliorates cognitive impairment by suppression of Aβ1-42 accumulation through inhibition of Akt/mTOR/p70S6K signaling and enhancement of autophagy in the hippocampus of LPS-induced mice.
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Affiliation(s)
- Lihong Zhu
- Department of Pathophysiology, School of Medicine, Jinan University, Guangzhou, PR China
| | - Qiongru Yuan
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou, PR China
| | - Zhaohao Zeng
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou, PR China
| | - Ruiyi Zhou
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou, PR China
| | - Rixin Luo
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou, PR China
| | - Jiawei Zhang
- Department of Pathophysiology, School of Medicine, Jinan University, Guangzhou, PR China
| | - Chi Kwan Tsang
- Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, PR, China
| | - Wei Bi
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangzhou, PR China.,Clinical Neuroscience Institute, The First Affiliated Hospital of Jinan University, Guangzhou, PR, China
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16
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Dow CT. Warm, Sweetened Milk at the Twilight of Immunity - Alzheimer's Disease - Inflammaging, Insulin Resistance, M. paratuberculosis and Immunosenescence. Front Immunol 2021; 12:714179. [PMID: 34421917 PMCID: PMC8375433 DOI: 10.3389/fimmu.2021.714179] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 07/09/2021] [Indexed: 01/22/2023] Open
Abstract
This article prosecutes a case against the zoonotic pathogen Mycobacterium avium ss. paratuberculosis (MAP) as a precipitant of Alzheimer’s disease (AD). Like the other major neurodegenerative diseases AD is, at its core, a proteinopathy. Aggregated extracellular amyloid protein plaques and intracellular tau protein tangles are the recognized protein pathologies of AD. Autophagy is the cellular housekeeping process that manages protein quality control and recycling, cellular metabolism, and pathogen elimination. Impaired autophagy and cerebral insulin resistance are invariant features of AD. With a backdrop of age-related low-grade inflammation (inflammaging) and heightened immune risk (immunosenescence), infection with MAP subverts glucose metabolism and further exhausts an already exhausted autophagic capacity. Increasingly, a variety of agents have been found to favorably impact AD; they are agents that promote autophagy and reduce insulin resistance. The potpourri of these therapeutic agents: mTOR inhibitors, SIRT1 activators and vaccines are seemingly random until one recognizes that all these agents also suppress intracellular mycobacterial infection. The zoonotic mycobacterial MAP causes a common fatal enteritis in ruminant animals. Humans are exposed to MAP from contaminated food products and from the environment. The enteritis in animals is called paratuberculosis or Johne’s disease; in humans, it is the putative cause of Crohn’s disease. Beyond Crohn’s, MAP is associated with an increasing number of inflammatory and autoimmune diseases: sarcoidosis, Blau syndrome, autoimmune diabetes, autoimmune thyroiditis, multiple sclerosis, and rheumatoid arthritis. Moreover, MAP has been associated with Parkinson’s disease. India is one county that has extensively studied the human bio-load of MAP; 30% of more than 28,000 tested individuals were found to harbor, or to have harbored, MAP. This article asserts an unfolding realization that MAP infection of humans 1) is widespread in its presence, 2) is wide-ranging in its zoonosis and 3) provides a plausible link connecting MAP to AD.
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Affiliation(s)
- Coad Thomas Dow
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, United States
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17
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Nasal Rifampicin Improves Cognition in a Mouse Model of Dementia with Lewy Bodies by Reducing α-Synuclein Oligomers. Int J Mol Sci 2021; 22:ijms22168453. [PMID: 34445158 PMCID: PMC8395129 DOI: 10.3390/ijms22168453] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 07/29/2021] [Accepted: 08/04/2021] [Indexed: 12/02/2022] Open
Abstract
α-Synuclein oligomers are thought to play an important role in the pathogenesis of dementia with Lewy bodies (DLB). There is no effective cure for DLB at present. Previously, we demonstrated that in APP- and tau-transgenic mice, oral or intranasal rifampicin reduced brain Aβ and tau oligomers and improved mouse cognition. In the present study, we expanded our research to DLB. Rifampicin was intranasally administered to 6-month-old A53T-mutant α-synuclein-transgenic mice at 0.1 mg/day for 1 month. The mice displayed memory impairment but no motor deficit at this age, indicating a suitable model of DLB. α-Synuclein pathologies were examined by the immunohistochemical/biochemical analyses of brain tissues. Cognitive function was evaluated by the Morris water maze test. Intranasal rifampicin significantly reduced the levels of [pSer129] α-synuclein in the hippocampus and α-synuclein oligomers in the visual cortex and hippocampus. The level of the presynaptic marker synaptophysin in the hippocampus was recovered to the level in non-transgenic littermates. In the Morris water maze, a significant improvement in spatial reference memory was observed in rifampicin-treated mice. Taken together with our previous findings, these results suggest that intranasal rifampicin is a promising remedy for the prevention of neurodegenerative dementia, including Alzheimer’s disease, frontotemporal dementia, and DLB.
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18
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Rampa A, Gobbi S, Belluti F, Bisi A. Tackling Alzheimer's Disease with Existing Drugs: A Promising Strategy for Bypassing Obstacles. Curr Med Chem 2021; 28:2305-2327. [PMID: 32867634 DOI: 10.2174/0929867327666200831140745] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/22/2020] [Accepted: 08/08/2020] [Indexed: 11/22/2022]
Abstract
The unmet need for the development of effective drugs to treat Alzheimer 's disease has been steadily growing, representing a major challenge in drug discovery. In this context, drug repurposing, namely the identification of novel therapeutic indications for approved or investigational compounds, can be seen as an attractive attempt to obtain new medications reducing both the time and the economic burden usually required for research and development programs. In the last years, several classes of drugs have evidenced promising beneficial effects in neurodegenerative diseases, and for some of them, preliminary clinical trials have been started. This review aims to illustrate some of the most recent examples of drugs reprofiled for Alzheimer's disease, considering not only the finding of new uses for existing drugs but also the new hypotheses on disease pathogenesis that could promote previously unconsidered therapeutic regimens. Moreover, some examples of structural modifications performed on existing drugs in order to obtain multifunctional compounds will also be described.
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Affiliation(s)
- Angela Rampa
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Via Belmeloro 6, I-40126 Bologna, Italy
| | - Silvia Gobbi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Via Belmeloro 6, I-40126 Bologna, Italy
| | - Federica Belluti
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Via Belmeloro 6, I-40126 Bologna, Italy
| | - Alessandra Bisi
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum-University of Bologna, Via Belmeloro 6, I-40126 Bologna, Italy
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19
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Butler L, Walker KA. The Role of Chronic Infection in Alzheimer’s Disease: Instigators, Co-conspirators, or Bystanders? CURRENT CLINICAL MICROBIOLOGY REPORTS 2021; 8:199-212. [DOI: 10.1007/s40588-021-00168-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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20
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Vigasova D, Nemergut M, Liskova B, Damborsky J. Multi-pathogen infections and Alzheimer's disease. Microb Cell Fact 2021; 20:25. [PMID: 33509204 PMCID: PMC7844946 DOI: 10.1186/s12934-021-01520-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 01/16/2021] [Indexed: 02/06/2023] Open
Abstract
Alzheimer's disease (AD) is a chronic neurodegenerative disease associated with the overproduction and accumulation of amyloid-β peptide and hyperphosphorylation of tau proteins in the brain. Despite extensive research on the amyloid-based mechanism of AD pathogenesis, the underlying cause of AD is not fully understood. No disease-modifying therapies currently exist, and numerous clinical trials have failed to demonstrate any benefits. The recent discovery that the amyloid-β peptide has antimicrobial activities supports the possibility of an infectious aetiology of AD and suggests that amyloid-β plaque formation might be induced by infection. AD patients have a weakened blood-brain barrier and immune system and are thus at elevated risk of microbial infections. Such infections can cause chronic neuroinflammation, production of the antimicrobial amyloid-β peptide, and neurodegeneration. Various pathogens, including viruses, bacteria, fungi, and parasites have been associated with AD. Most research in this area has focused on individual pathogens, with herpesviruses and periodontal bacteria being most frequently implicated. The purpose of this review is to highlight the potential role of multi-pathogen infections in AD. Recognition of the potential coexistence of multiple pathogens and biofilms in AD's aetiology may stimulate the development of novel approaches to its diagnosis and treatment. Multiple diagnostic tests could be applied simultaneously to detect major pathogens, followed by anti-microbial treatment using antiviral, antibacterial, antifungal, and anti-biofilm agents.
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Affiliation(s)
- Dana Vigasova
- International Clinical Research Center, St. Anne’s University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
- Department of Experimental Biology and RECETOX, Faculty of Science, Loschmidt Laboratories, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Michal Nemergut
- Department of Experimental Biology and RECETOX, Faculty of Science, Loschmidt Laboratories, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Barbora Liskova
- Department of Experimental Biology and RECETOX, Faculty of Science, Loschmidt Laboratories, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Jiri Damborsky
- International Clinical Research Center, St. Anne’s University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
- Department of Experimental Biology and RECETOX, Faculty of Science, Loschmidt Laboratories, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
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21
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Antimicrobial therapy and the potential mechanisms in Alzheimer's disease. Neurosci Lett 2020; 741:135464. [PMID: 33166642 DOI: 10.1016/j.neulet.2020.135464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/22/2020] [Accepted: 10/23/2020] [Indexed: 11/20/2022]
Abstract
Alzheimer's disease treatments have been a heavily investigated research area, however, new drugs have failed one after another. Some scientists have begun to reposition drugs, including antimicrobial agents. Here, the treatment effects of nine antimicrobial agents on Alzheimer's disease and their possible therapeutic mechanisms are described to clarify their efficacy. In vivo and in vitro studies are quite encouraging and tend to demonstrate that antimicrobial therapy is effective in Alzheimer's disease. Nevertheless, unsatisfactory clinical efficacy, side effects, and insufficient knowledge have yet to be overcome. Further laboratory and clinical studies are required to recommend antimicrobial treatment regimens.
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22
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Burns MR, McFarland NR. Current Management and Emerging Therapies in Multiple System Atrophy. Neurotherapeutics 2020; 17:1582-1602. [PMID: 32767032 PMCID: PMC7851250 DOI: 10.1007/s13311-020-00890-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Multiple system atrophy (MSA) is a progressive neurodegenerative disease variably associated with motor, nonmotor, and autonomic symptoms, resulting from putaminal and cerebellar degeneration and associated with glial cytoplasmic inclusions enriched with α-synuclein in oligodendrocytes and neurons. Although symptomatic treatment of MSA can provide significant improvements in quality of life, the benefit is often partial, limited by adverse effects, and fails to treat the underlying cause. Consistent with the multisystem nature of the disease and evidence that motor symptoms, autonomic failure, and depression drive patient assessments of quality of life, treatment is best achieved through a coordinated multidisciplinary approach driven by the patient's priorities and goals of care. Research into disease-modifying therapies is ongoing with a particular focus on synuclein-targeted therapies among others. This review focuses on both current management and emerging therapies for this devastating disease.
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Affiliation(s)
- Matthew R. Burns
- Norman Fixel Institute for Neurological Diseases at UFHealth, Movement Disorders Division, Department of Neurology, University of Florida, 3009 SW Williston Rd, Gainesville, FL 32608 USA
| | - Nikolaus R. McFarland
- Norman Fixel Institute for Neurological Diseases at UFHealth, Movement Disorders Division, Department of Neurology, University of Florida, 3009 SW Williston Rd, Gainesville, FL 32608 USA
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23
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Amyloid Beta-Peptide Increases BACE1 Translation through the Phosphorylation of the Eukaryotic Initiation Factor-2 α. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:2739459. [PMID: 33014268 PMCID: PMC7525306 DOI: 10.1155/2020/2739459] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 09/02/2020] [Accepted: 09/08/2020] [Indexed: 12/02/2022]
Abstract
Alzheimer's disease (AD) is tightly linked to oxidative stress since amyloid beta-peptide (Aβ) aggregates generate free radicals. Moreover, the aggregation of Aβ is increased by oxidative stress, and the neurotoxicity induced by the oligomers and fibrils is in part mediated by free radicals. Interestingly, it has been reported that oxidative stress can also induce BACE1 transcription and expression. BACE1 is the key enzyme in the cleavage of the amyloid precursor protein to produce Aβ, and the expression of this enzyme has been previously shown to be enhanced in the brains of Alzheimer's patients. Here, we have found that BACE1 expression is increased in the hippocampi from AD patients at both the early (Braak stage II) and late (Braak stage VI) stages of the disease as studied by immunohistochemistry and western blot. To address the role of Aβ and oxidative stress in the regulation of BACE1 expression, we have analyzed the effect of subtoxic concentrations of Aβ oligomers (0.25 μM) and H2O2 (10 mM) on a human neuroblastoma cell line. Firstly, our results show that Aβ oligomers and H2O2 induce an increase of BACE1 mRNA as we studied by qPCR. Regarding BACE1 translation, it is dependent on the phosphorylation of the eukaryotic initiation factor 2α (eIF2α), since BACE1 mRNA bears a 5′UTR that avoids its translation under basal conditions. BACE1 5′UTR contains four upstream initiating codons (uAUGs), and its translation is activated when eIF2α is phosphorylated. Consistently, we have obtained that Aβ oligomers and H2O2 increase the levels of BACE1 and p-eIF2α assayed by western blot and confocal microscopy. Our results suggest that Aβ oligomers increase BACE1 translation by phosphorylating eIF2α in a process that involves oxidative stress and conforms a pathophysiological loop, where the Aβ once aggregated favors its own production continuously by the increase in BACE1 expression as observed in AD patients.
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Bulgart HR, Neczypor EW, Wold LE, Mackos AR. Microbial involvement in Alzheimer disease development and progression. Mol Neurodegener 2020; 15:42. [PMID: 32709243 PMCID: PMC7382139 DOI: 10.1186/s13024-020-00378-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 04/29/2020] [Indexed: 02/08/2023] Open
Abstract
Alzheimer disease (AD) is the most prominent form of dementia and the 5th leading cause of death in individuals over 65. AD is a complex disease stemming from genetic, environmental, and lifestyle factors. It is known that AD patients have increased levels of senile plaques, neurofibrillary tangles, and neuroinflammation; however, the mechanism(s) by which the plaques, tangles, and neuroinflammation manifest remain elusive. A recent hypothesis has emerged that resident bacterial populations contribute to the development and progression of AD by contributing to neuroinflammation, senile plaque formation, and potentially neurofibrillary tangle accumulation (Fig. 1). This review will highlight recent studies involved in elucidating microbial involvement in AD development and progression.
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Affiliation(s)
- Hannah R. Bulgart
- Biomedical Sciences Graduate Program, College of Medicine, The Ohio State University, Columbus, OH USA
| | - Evan W. Neczypor
- Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, OH USA
- College of Nursing, The Ohio State University, 1585 Neil Ave, Columbus, OH 43210 USA
| | - Loren E. Wold
- Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, OH USA
- College of Nursing, The Ohio State University, 1585 Neil Ave, Columbus, OH 43210 USA
- Department of Physiology and Cell Biology, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH USA
| | - Amy R. Mackos
- College of Nursing, The Ohio State University, 1585 Neil Ave, Columbus, OH 43210 USA
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Iqbal UH, Zeng E, Pasinetti GM. The Use of Antimicrobial and Antiviral Drugs in Alzheimer's Disease. Int J Mol Sci 2020; 21:E4920. [PMID: 32664669 PMCID: PMC7404195 DOI: 10.3390/ijms21144920] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/09/2020] [Accepted: 07/10/2020] [Indexed: 12/15/2022] Open
Abstract
The aggregation and accumulation of amyloid-β plaques and tau proteins in the brain have been central characteristics in the pathophysiology of Alzheimer's disease (AD), making them the focus of most of the research exploring potential therapeutics for this neurodegenerative disease. With success in interventions aimed at depleting amyloid-β peptides being limited at best, a greater understanding of the physiological role of amyloid-β peptides is needed. The development of amyloid-β plaques has been determined to occur 10-20 years prior to AD symptom manifestation, hence earlier interventions might be necessary to address presymptomatic AD. Furthermore, recent studies have suggested that amyloid-β peptides may play a role in innate immunity as an antimicrobial peptide. These findings, coupled with the evidence of pathogens such as viruses and bacteria in AD brains, suggests that the buildup of amyloid-β plaques could be a response to the presence of viruses and bacteria. This has led to the foundation of the antimicrobial hypothesis for AD. The present review will highlight the current understanding of amyloid-β, and the role of bacteria and viruses in AD, and will also explore the therapeutic potential of antimicrobial and antiviral drugs in Alzheimer's disease.
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Affiliation(s)
| | | | - Giulio M. Pasinetti
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (U.H.I.); (E.Z.)
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Long-term exposure to constant light induces dementia, oxidative stress and promotes aggregation of sub-pathological Aβ42 in Wistar rats. Pharmacol Biochem Behav 2020; 192:172892. [DOI: 10.1016/j.pbb.2020.172892] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 03/02/2020] [Accepted: 03/02/2020] [Indexed: 12/17/2022]
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Cho KS, Lee JH, Cho J, Cha GH, Song GJ. Autophagy Modulators and Neuroinflammation. Curr Med Chem 2020; 27:955-982. [PMID: 30381067 DOI: 10.2174/0929867325666181031144605] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Revised: 08/20/2018] [Accepted: 10/21/2018] [Indexed: 12/12/2022]
Abstract
BACKGROUND Neuroinflammation plays a critical role in the development and progression of various neurological disorders. Therefore, various studies have focused on the development of neuroinflammation inhibitors as potential therapeutic tools. Recently, the involvement of autophagy in the regulation of neuroinflammation has drawn substantial scientific interest, and a growing number of studies support the role of impaired autophagy in the pathogenesis of common neurodegenerative disorders. OBJECTIVE The purpose of this article is to review recent research on the role of autophagy in controlling neuroinflammation. We focus on studies employing both mammalian cells and animal models to evaluate the ability of different autophagic modulators to regulate neuroinflammation. METHODS We have mostly reviewed recent studies reporting anti-neuroinflammatory properties of autophagy. We also briefly discussed a few studies showing that autophagy modulators activate neuroinflammation in certain conditions. RESULTS Recent studies report neuroprotective as well as anti-neuroinflammatory effects of autophagic modulators. We discuss the possible underlying mechanisms of action of these drugs and their potential limitations as therapeutic agents against neurological disorders. CONCLUSION Autophagy activators are promising compounds for the treatment of neurological disorders involving neuroinflammation.
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Affiliation(s)
- Kyoung Sang Cho
- Department of Biological Sciences, Konkuk University, Seoul, Korea
| | - Jang Ho Lee
- Translational Brain Research Center, International St. Mary's Hospital, Catholic Kwandong University, Incheon, Korea
| | - Jeiwon Cho
- Translational Brain Research Center, International St. Mary's Hospital, Catholic Kwandong University, Incheon, Korea.,Department of Medical Science, College of Medicine, Catholic Kwandong University, Gangneung, Gangwon-do, Korea
| | - Guang-Ho Cha
- Department of Medical Science, College of Medicine, Chungnam National University, 35015 Daejeon, Korea
| | - Gyun Jee Song
- Translational Brain Research Center, International St. Mary's Hospital, Catholic Kwandong University, Incheon, Korea.,Department of Medical Science, College of Medicine, Catholic Kwandong University, Gangneung, Gangwon-do, Korea
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Diker N, Caglayan B, Helvacioglu F, Kilic E. The effect of systemic rifampicin treatment on inferior alveolar nerve regeneration in rats following crush injury. Eur J Oral Sci 2020; 128:183-189. [PMID: 32236990 DOI: 10.1111/eos.12691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2020] [Indexed: 11/28/2022]
Abstract
Axonal regeneration of the inferior alveolar nerve (IAN) is a therapeutic target for functional recovery after peripheral nerve injury. Rifampicin exerts anti-apoptotic, anti-inflammatory, and anti-oxidant effects on nerve tissues that may enhance functional recovery after peripheral nerve injury. The aim of the present study was to evaluate the therapeutic effects of systemic rifampicin following IAN crush injury. Following the nerve crush injuries of the IAN, 24 Sprague-Dawley rats were randomly divided into three groups to receive daily intraperitoneal injections of either vehicle, 5 mg kg-1 rifampicin, or 20 mg kg-1 rifampicin. Twenty-four days after induction of nerve injuries, Fluorogold (FG) was injected over the mental foramen for the evaluation of neuronal survival. At the end of the four-week period, histologic and histomorphometric examination of IAN samples were performed and FG positive cells were counted in the trigeminal ganglion sections. FG positive cells were significantly more frequent in the 20 and 5 mg kg-1 rifampicin groups than in the vehicle-treated group. Electron microscopic analyses revealed that the percentage of axons with optimum g-ratio was significantly lower in the vehicle group than in both treatment groups. In conclusion, systemic rifampicin treatment can enhance peripheral nerve regeneration.
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Affiliation(s)
- Nurettin Diker
- Department of Oral and Maxillofacial Surgery, Bezmialem Vakif University, Istanbul, Turkey.,Department of Physiology, Istanbul Medipol University, Istanbul, Turkey.,Regenerative and Restorative Medicine Research Center, Istanbul Medipol University, Istanbul, Turkey
| | - Berrak Caglayan
- Regenerative and Restorative Medicine Research Center, Istanbul Medipol University, Istanbul, Turkey.,Department of Medical Biology, Istanbul Medipol University, Istanbul, Turkey
| | - Fatma Helvacioglu
- Department of Histology and Embryology, Baskent University, Ankara, Turkey
| | - Ertugrul Kilic
- Department of Physiology, Istanbul Medipol University, Istanbul, Turkey.,Regenerative and Restorative Medicine Research Center, Istanbul Medipol University, Istanbul, Turkey
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29
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Heras-Garvin A, Stefanova N. MSA: From basic mechanisms to experimental therapeutics. Parkinsonism Relat Disord 2020; 73:94-104. [PMID: 32005598 DOI: 10.1016/j.parkreldis.2020.01.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 01/14/2020] [Accepted: 01/19/2020] [Indexed: 01/16/2023]
Abstract
Multiple system atrophy (MSA) is a rare and fatal neurodegenerative disorder characterized by rapidly progressive autonomic and motor dysfunction. Pathologically, MSA is mainly characterized by the abnormal accumulation of misfolded α-synuclein in the cytoplasm of oligodendrocytes, which plays a major role in the pathogenesis of the disease. Striatonigral degeneration and olivopontecerebellar atrophy underlie the motor syndrome, while degeneration of autonomic centers defines the autonomic failure in MSA. At present, there is no treatment that can halt or reverse its progression. However, over the last decade several studies in preclinical models and patients have helped to better understand the pathophysiological events underlying MSA. The etiology of this fatal disorder remains unclear and may be multifactorial, caused by a combination of factors which may serve as targets for novel therapeutic approaches. In this review, we summarize the current knowledge about the etiopathogenesis and neuropathology of MSA, its different preclinical models, and the main disease modifying therapies that have been used so far or that are planned for future clinical trials.
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Affiliation(s)
- Antonio Heras-Garvin
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, Austria.
| | - Nadia Stefanova
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, Austria.
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30
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Viswanathan GK, Paul A, Gazit E, Segal D. Naphthoquinone Tryptophan Hybrids: A Promising Small Molecule Scaffold for Mitigating Aggregation of Amyloidogenic Proteins and Peptides. Front Cell Dev Biol 2019; 7:242. [PMID: 31750300 PMCID: PMC6843079 DOI: 10.3389/fcell.2019.00242] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 10/02/2019] [Indexed: 12/22/2022] Open
Abstract
A current challenge faced by researchers is the lack of disease-modifying therapeutics for amyloid formation that is associated with several human diseases. Although the monomeric proteins or peptides involved in various amyloidogenic diseases do not have amino acid sequence homology, there appears to be a structural correlation among the amyloid assemblies, which are responsible for distinct pathological conditions. Here, we review our work on Naphthoquinone Tryptophan (NQTrp) hybrids, a small molecule scaffold that can generically modulate neuronal and non-neuronal amyloid aggregation both in vitro and in vivo. NQTrp reduces the net amyloid load by inhibiting the process of amyloid formation and disassembling the pre-formed fibrils, both in a dose-dependent manner. As a plausible mechanism of action, NQTrp effectively forms hydrogen bonding and hydrophobic interactions, such as π-π stacking, with the vital residues responsible for the initial nucleation of protein/peptide aggregation. This review highlights the effectiveness of the NQTrp hybrid scaffold for developing novel small molecule modulators of amyloid aggregation.
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Affiliation(s)
- Guru KrishnaKumar Viswanathan
- Department of Molecular Microbiology and Biotechnology, School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Ashim Paul
- Department of Molecular Microbiology and Biotechnology, School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Ehud Gazit
- Department of Molecular Microbiology and Biotechnology, School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Tel Aviv, Israel
| | - Daniel Segal
- Department of Molecular Microbiology and Biotechnology, School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Tel Aviv, Israel.,Interdisciplinary Sagol School of Neurosciences, Tel Aviv University, Tel Aviv, Israel
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31
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Neo Shin N, Jeon H, Jung Y, Baek S, Lee S, Yoo HC, Bae GH, Park K, Yang SH, Han JM, Kim I, Kim Y. Fluorescent 1,4-Naphthoquinones To Visualize Diffuse and Dense-Core Amyloid Plaques in APP/PS1 Transgenic Mouse Brains. ACS Chem Neurosci 2019; 10:3031-3044. [PMID: 31016960 DOI: 10.1021/acschemneuro.9b00093] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Recent clinical approvals of brain imaging radiotracers targeting amyloid-β provided clinicians the tools to detect and confirm Alzheimer's disease pathology without autopsy or biopsy. While current imaging agents are effective in postsymptomatic Alzheimer's patients, there is much room for improvement in earlier diagnosis, hence prompting a need for new and improved amyloid imaging agents. Here we synthesized 41 novel 1,4-naphthoquinone derivatives and initially discovered 14 antiamyloidogenic compounds via in vitro amyloid-β aggregation assay; however, qualitative analyses of these compounds produced conflicting results and required further investigation. Follow-up docking and biophysical studies revealed that four of these compounds penetrate the blood-brain barrier, directly bind to amyloid-β aggregates, and enhance fluorescence properties upon interaction. These compounds specifically stain both diffuse and dense-core amyloid-β plaques in brain sections of APP/PS1 double transgenic Alzheimer's mouse models. Our findings suggest 1,4-naphthoquinones as a new scaffold for amyloid-β imaging agents for early stage Alzheimer's.
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Affiliation(s)
- Naewoo Neo Shin
- Integrated Science and Engineering Division, Yonsei University, Incheon 21983, Republic of Korea
| | - Hanna Jeon
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
| | - Youngeun Jung
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
| | - Seungyeop Baek
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
- Department of Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Sejin Lee
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
| | - Hee Chan Yoo
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
| | - Gi Hun Bae
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
| | - Keunwan Park
- Natural Product Informatics Research Center, Korea Institute of Science and Technology, Gangneung 25451, Republic of Korea
| | - Seung-Hoon Yang
- Department of Medical Biotechnology, College of Life Science and Biotechnology, Dongguk University, Seoul 04620, Republic of Korea
| | - Jung Min Han
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
| | - Ikyon Kim
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
| | - YoungSoo Kim
- Integrated Science and Engineering Division, Yonsei University, Incheon 21983, Republic of Korea
- Department of Pharmacy and Yonsei Institute of Pharmaceutical Science, Yonsei University, Incheon 21983, Republic of Korea
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Sudhakar S, Mani E. Rapid Dissolution of Amyloid β Fibrils by Silver Nanoplates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:6962-6970. [PMID: 31030521 DOI: 10.1021/acs.langmuir.9b00080] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Plaques of amyloid beta (Aβ) protein are associated with neurodegenerative diseases, and preventing their formation and dissolution of plaques are essential to the development of therapeutics. In this study, silver triangular nanoplates (AgTNPs) are shown to dissolve mature Aβ fibrils because of their plasmonic photothermal property. Mature Aβ fibrils treated with AgTNPs under near-infrared (NIR)-illuminated conditions are dissolved in less than 1 h, while an equal concentration of silver spherical nanoparticles took about 70 h. The concentration of the fibrils decreased from 10 to 0.3 μM upon treating the amyloid fibrils with AgTNPs under NIR. AgTNPs are also shown to prevent the formation of Aβ fibrils by selective binding to the positively charged amyloidogenic sequence of the Aβ monomer. The kinetics of inhibition by AgTNPs follows the predictions of the detailed kinetic model (Ramesh et al., Langmuir 2018, 34, 4004-4012). The kinetics of dissolution and inhibition are characterized by Congo red/ThT assay, transmission electronic microscopy, atomic force microscopy, and attenuated total reflectance Fourier transform-infrared spectroscopy. Cell viability studies on SH-SY5Y and BE-(2)-C cells using 3-[4,5-dimethy-lthi-azol-2-yl]-2,5-diphenyl-tetrazdium bromide and lactate dehydrogenase assay show that the viability of the cells increased from 33 to 70% on treating the cells with AgTNP-incubated Aβ fibrils compared to the mature Aβ fibrils. The study provides new insights to design plasmonic nanoparticle-based therapeutics to cure neurodegenerative diseases.
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Affiliation(s)
- Swathi Sudhakar
- Polymer Engineering and Colloid Science Laboratory, Department of Chemical Engineering , Indian Institute of Technology, Madras , Chennai 600 036 , India
| | - Ethayaraja Mani
- Polymer Engineering and Colloid Science Laboratory, Department of Chemical Engineering , Indian Institute of Technology, Madras , Chennai 600 036 , India
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Ono K, Tsuji M. Pharmacological Potential of Cilostazol for Alzheimer's Disease. Front Pharmacol 2019; 10:559. [PMID: 31191308 PMCID: PMC6540873 DOI: 10.3389/fphar.2019.00559] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 05/03/2019] [Indexed: 12/23/2022] Open
Abstract
Alzheimer’s disease (AD), a slow progressive form of dementia, is clinically characterized by cognitive dysfunction and memory impairment and neuropathologically characterized by the accumulation of extracellular plaques containing amyloid β-protein (Aβ) and neurofibrillary tangles containing tau in the brain, with neuronal degeneration and high level of oxidative stress. The current treatments for AD, e.g., acetylcholinesterase inhibitors (AChEIs), have efficacies limited to symptom improvement. Although there are various approaches to the disease modifying therapies of AD, none of them can be used alone for actual treatment, and combination therapy may be needed for amelioration of the progression. There are reports that cilostazol (CSZ) suppressed cognitive decline progression in patients with mild cognitive impairment or stable AD receiving AChEIs. Previously, we showed that CSZ suppressed Aβ-induced neurotoxicity in SH-SY5Y cells via coincident inhibition of oxidative stress, as demonstrated by reduced activity of nicotinamide adenine dinucleotide phosphate oxidase, accumulation of reactive oxygen species, and signaling of mitogen-activated protein kinase. CSZ also rescued cognitive impairment and promoted soluble Aβ clearance in a mouse model of cerebral amyloid angiopathy. Mature Aβ fibrils have long been considered the primary neurodegenerative factors in AD; however, recent evidence indicates soluble oligomers to initiate the neuronal and synaptic dysfunction related to AD and other protein-misfolding diseases. Further underscoring the potential of CSZ for AD treatment, we recently described the inhibitory effects of CSZ on Aβ oligomerization and aggregation in vitro. In this review, we discuss the possibility of CSZ as a potential disease-modifying therapy for the prevention or delay of AD.
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Affiliation(s)
- Kenjiro Ono
- Division of Neurology, Department of Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Mayumi Tsuji
- Department of Pharmacology, Showa University School of Medicine, Tokyo, Japan
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Funk GA, Menuey EM, Cole KA, Schuman TP, Kilway KV, McIff TE. Radical scavenging of poly(methyl methacrylate) bone cement by rifampin and clinically relevant properties of the rifampin-loaded cement. Bone Joint Res 2019; 8:81-89. [PMID: 30915214 PMCID: PMC6397418 DOI: 10.1302/2046-3758.82.bjr-2018-0170.r2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Objectives The objective of this study was to characterize the effect of rifampin incorporation into poly(methyl methacrylate) (PMMA) bone cement. While incompatibilities between the two materials have been previously noted, we sought to identify and quantify the cause of rifampin’s effects, including alterations in curing properties, mechanical strength, and residual monomer content. Methods Four cement groups were prepared using commercial PMMA bone cement: a control; one with 1 g of rifampin; and one each with equimolar amounts of ascorbic acid or hydroquinone relative to the amount of rifampin added. The handling properties, setting time, exothermic output, and monomer loss were measured throughout curing. The mechanical strength of each group was tested over 14 days. A radical scavenging assay was used to assess the scavenging abilities of rifampin and its individual moieties. Results Compared with control, the rifampin-incorporated cement had a prolonged setting time and a reduction in exothermic output during polymerization. The rifampin cement showed significantly reduced strength and was below the orthopaedic weight-bearing threshold of 70 MPa. Based on the radical scavenging assay and strength tests, the hydroquinone structure within rifampin was identified as the polymerization inhibitor. Conclusion The incorporation of rifampin into PMMA bone cement interferes with the cement’s radical polymerization. This interference is due to the hydroquinone moiety within rifampin. This combination alters the cement’s handling and curing properties, and lowers the strength below the threshold for weight-bearing applications. Additionally, the incomplete polymerization leads to increased toxic monomer output, which discourages its use even in non-weight-bearing applications. Cite this article: G. A. Funk, E. M. Menuey, K. A. Cole, T. P. Schuman, K. V. Kilway, T. E. McIff. Radical scavenging of poly(methyl methacrylate) bone cement by rifampin and clinically relevant properties of the rifampin-loaded cement. Bone Joint Res 2019;8:81–89. DOI: 10.1302/2046-3758.82.BJR-2018-0170.R2.
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Affiliation(s)
- G A Funk
- Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - E M Menuey
- Department of Chemistry, University of Missouri-Kansas City, Kansas City, Missouri, USA
| | - K A Cole
- Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - T P Schuman
- Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri, USA
| | - K V Kilway
- Department of Chemistry, University of Missouri-Kansas City, Kansas City, Missouri, USA
| | - T E McIff
- Department of Orthopedic Surgery, University of Kansas Medical Center, Kansas City, Kansas, USA
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Olfati N, Shoeibi A, Litvan I. Progress in the treatment of Parkinson-Plus syndromes. Parkinsonism Relat Disord 2019; 59:101-110. [DOI: 10.1016/j.parkreldis.2018.10.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 09/27/2018] [Accepted: 10/01/2018] [Indexed: 01/04/2023]
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36
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Zahednasab H, Firouzi M, Kaboudanian-Ardestani S, Mojallal-Tabatabaei Z, Karampour S, Keyvani H. The protective effect of rifampicin on behavioral deficits, biochemical, and neuropathological changes in a cuprizone model of demyelination. Cytokine 2019; 113:417-426. [DOI: 10.1016/j.cyto.2018.10.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 09/16/2018] [Accepted: 10/18/2018] [Indexed: 12/19/2022]
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37
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Lin MZ, Chai WM, Zheng YL, Huang Q, Ou-Yang C. Inhibitory kinetics and mechanism of rifampicin on α-glucosidase: Insights from spectroscopic and molecular docking analyses. Int J Biol Macromol 2018; 122:1244-1252. [PMID: 30227201 DOI: 10.1016/j.ijbiomac.2018.09.077] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 09/08/2018] [Accepted: 09/13/2018] [Indexed: 01/12/2023]
Abstract
α-Glucosidase is a critical enzyme associated with diabetes mellitus, and the inhibitors of the enzyme play important roles in the treatment of the disease. In this study, the inhibitory effect and mechanism of rifampicin on α-glucosidase were investigated by multispectroscopic methods along with molecular docking technique. The results showed that rifampicin inhibited α-glucosidase activity prominently (IC50 = 135 ± 1.2 μM) in a reversible and competitive-type manner. The fluorescence intensity of α-glucosidase was quenched by rifampicin through forming rifampicin-α-glucosidase complex in a static procedure. And the formation of the rifampicin-α-glucosidase complex was driven spontaneously by hydrophobic forces and hydrogen bonds. The results obtained from molecular docking further indicated that hydrophobic forces were formed between rifampicin and amino acid residues Phe 173, Pro151, and hydrogen bonds were generated by the interactions of rifampicin with residues Ser 180, Asn 414, Gly160, and Gly161 of α-glucosidase. Moreover, it was found that the binding of rifampicin to α-glucosidase could alter the conformation of the enzyme to make it steady, and the binding distance was estimated to be 1.02 nm. Therefore, this study confirmed a novel α-glucosidase inhibitor and possibly contributed to the improvement of newfangled anti-diabetic agent.
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Affiliation(s)
- Mei-Zhen Lin
- College of Life Science and Key Laboratory of Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, China
| | - Wei-Ming Chai
- College of Life Science and Key Laboratory of Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, China.
| | - Yun-Ling Zheng
- College of Life Science and Key Laboratory of Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, China
| | - Qian Huang
- College of Life Science and Key Laboratory of Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, China
| | - Chong Ou-Yang
- College of Life Science and Key Laboratory of Ministry of Education, Jiangxi Normal University, Nanchang, Jiangxi 330022, China
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Ali AE, Mahdy HM, Elsherbiny DM, Azab SS. Rifampicin ameliorates lithium-pilocarpine-induced seizures, consequent hippocampal damage and memory deficit in rats: Impact on oxidative, inflammatory and apoptotic machineries. Biochem Pharmacol 2018; 156:431-443. [PMID: 30195730 DOI: 10.1016/j.bcp.2018.09.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 09/05/2018] [Indexed: 01/28/2023]
Abstract
Epilepsy is one of the serious neurological sequelae of bacterial meningitis. Rifampicin, the well-known broad spectrum antibiotic, is clinically used for chemoprophylaxis of meningitis. Besides its antibiotic effects, rifampicin has been proven to be an effective neuroprotective candidate in various experimental models of neurological diseases. In addition, rifampicin was found to have promising antioxidant, anti-inflammatory and anti-apoptotic effects. Herein, we investigated the anticonvulsant effect of rifampicin at experimental meningitis dose (20 mg/kg, i.p.) using lithium-pilocarpine model of status epilepticus (SE) in rats. Additionally, we studied the effect of rifampicin on seizure induced histopathological, neurochemical and behavioral abnormalities. Our study showed that rifampicin pretreatment attenuated seizure activity and the resulting hippocampal insults marked by hematoxylin and eosin. Markers of oxidative stress, neuroinflammation and apoptosis were evaluated, in the hippocampus, 24 h after SE induction. We found that rifampicin pretreatment suppressed oxidative stress as indicated by normalized malondialdehyde and glutathione levels. Rifampicin pretreatment attenuated SE-induced neuroinflammation and decreased the hippocampal expression of interleukin-1β, tumor necrosis factor-α, nuclear factor kappa-B, and cyclooxygenase-2. Moreover, rifampicin mitigated SE-induced neuronal apoptosis as indicated by fewer positive cytochrome c immunostained cells and lower caspase-3 activity in the hippocampus. Furthermore, Morris water maze testing at 7 days after SE induction showed that rifampicin pretreatment can improve cognitive dysfunction. Therefore, rifampicin, currently used in the management of meningitis, has a potential additional advantage of ameliorating its epileptic sequelae.
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Affiliation(s)
- Alaa E Ali
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Heba M Mahdy
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Doaa M Elsherbiny
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Samar S Azab
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt.
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Bortolanza M, Nascimento GC, Socias SB, Ploper D, Chehín RN, Raisman-Vozari R, Del-Bel E. Tetracycline repurposing in neurodegeneration: focus on Parkinson’s disease. J Neural Transm (Vienna) 2018; 125:1403-1415. [DOI: 10.1007/s00702-018-1913-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 08/03/2018] [Indexed: 01/03/2023]
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40
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Newfound effect of N-acetylaspartate in preventing and reversing aggregation of amyloid-beta in vitro. Neurobiol Dis 2018; 117:161-169. [PMID: 29859874 DOI: 10.1016/j.nbd.2018.05.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 05/11/2018] [Accepted: 05/30/2018] [Indexed: 12/23/2022] Open
Abstract
Although N-acetylaspartate (NAA) has long been recognized as the most abundant amino acid in neurons by far, its primary role has remained a mystery. Based on its unique tertiary structure, we explored the potential of NAA to modulate aggregation of amyloid-beta (Aβ) peptide 1-42 via multiple corroborating aggregation assays along with electron microscopy. Thioflavin-T fluorescence assay demonstrated that at physiological concentrations, NAA substantially inhibited the initiation of Aβ fibril formation. In addition, NAA added after 25 min of Aβ aggregation was shown to break up preformed fibrils. Electron microscopy analysis confirmed the absence of mature fibrils following NAA treatment. Furthermore, fluorescence correlation spectroscopy and dynamic light scattering measurements confirmed significant reductions in Aβ fibril hydrodynamic radius following treatment with NAA. These results suggest that physiological levels of NAA could play an important role in controlling Aβ aggregation in vivo where they are both found in the same neuronal compartments.
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41
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Durães F, Pinto M, Sousa E. Old Drugs as New Treatments for Neurodegenerative Diseases. Pharmaceuticals (Basel) 2018; 11:ph11020044. [PMID: 29751602 PMCID: PMC6027455 DOI: 10.3390/ph11020044] [Citation(s) in RCA: 168] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 05/07/2018] [Accepted: 05/08/2018] [Indexed: 12/12/2022] Open
Abstract
Neurodegenerative diseases are increasing in number, given that the general global population is becoming older. They manifest themselves through mechanisms that are not fully understood, in many cases, and impair memory, cognition and movement. Currently, no neurodegenerative disease is curable, and the treatments available only manage the symptoms or halt the progression of the disease. Therefore, there is an urgent need for new treatments for this kind of disease, since the World Health Organization has predicted that neurodegenerative diseases affecting motor function will become the second-most prevalent cause of death in the next 20 years. New therapies can come from three main sources: synthesis, natural products, and existing drugs. This last source is known as drug repurposing, which is the most advantageous, since the drug’s pharmacokinetic and pharmacodynamic profiles are already established, and the investment put into this strategy is not as significant as for the classic development of new drugs. There have been several studies on the potential of old drugs for the most relevant neurodegenerative diseases, including Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, Multiple Sclerosis and Amyotrophic Lateral Sclerosis.
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Affiliation(s)
- Fernando Durães
- Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
- CIIMAR, Interdisciplinary Center of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos P, 4450-208 Matosinhos, Portugal.
| | - Madalena Pinto
- Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
- CIIMAR, Interdisciplinary Center of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos P, 4450-208 Matosinhos, Portugal.
| | - Emília Sousa
- Laboratory of Organic and Pharmaceutical Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
- CIIMAR, Interdisciplinary Center of Marine and Environmental Research, University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos P, 4450-208 Matosinhos, Portugal.
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42
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Yulug B, Hanoglu L, Ozansoy M, Isık D, Kilic U, Kilic E, Schabitz WR. Therapeutic role of rifampicin in Alzheimer's disease. Psychiatry Clin Neurosci 2018; 72:152-159. [PMID: 29315976 DOI: 10.1111/pcn.12637] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 12/06/2017] [Accepted: 12/17/2017] [Indexed: 12/11/2022]
Abstract
Rifampicin exerts significant brain protective functions in multiple experimental models. Here we summarize the underlying mechanisms of the neuroprotective and pro-cognitive effects of rifampicin that are mediated by its anti-inflammatory, anti-tau, anti-amyloid, and cholinergic effects. Beyond suggesting that rifampicin shows strong brain protective effects in preclinical models of Alzheimer's disease, we also provide substantial clinical evidence for the neuroprotective and pro-cognitive effects of rifampicin. Future neuroimaging studies combined with clinical assessment scores are the following steps to be taken in this field of research.
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Affiliation(s)
- Burak Yulug
- Department of Neurology, Istanbul Medipol University, Istanbul, Turkey.,Department of Restorative and Regenerative Medicine, Istanbul Medipol University, Istanbul, Turkey
| | - Lütfü Hanoglu
- Department of Neurology, Istanbul Medipol University, Istanbul, Turkey.,Department of Restorative and Regenerative Medicine, Istanbul Medipol University, Istanbul, Turkey
| | - Mehmet Ozansoy
- Department of Restorative and Regenerative Medicine, Istanbul Medipol University, Istanbul, Turkey.,Department of Physiology, International School of Medicine, Istanbul Medipol University, Istanbul, Turkey
| | - Dogan Isık
- Department of Psychiatry, Istanbul Medipol University, Istanbul, Turkey
| | - Ulkan Kilic
- Department of Medical Biology, Faculty of Medicine, University of Health Sciences, Istanbul, Turkey
| | - Ertugrul Kilic
- Department of Restorative and Regenerative Medicine, Istanbul Medipol University, Istanbul, Turkey.,Department of Physiology, International School of Medicine, Istanbul Medipol University, Istanbul, Turkey
| | - Wolf Rüdiger Schabitz
- Department of Neurology, Bethel, EVKB, Bielefeld, University of Münster, Münster, Germany
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43
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Siddiqi MK, Alam P, Chaturvedi SK, Khan MV, Nusrat S, Malik S, Khan RH. Capreomycin inhibits the initiation of amyloid fibrillation and suppresses amyloid induced cell toxicity. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:549-557. [PMID: 29496560 DOI: 10.1016/j.bbapap.2018.02.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 02/11/2018] [Accepted: 02/23/2018] [Indexed: 12/20/2022]
Abstract
Protein aggregation and amyloid fibrillation are responsible for several serious pathological conditions (like type II diabetes, Alzheimer's and Parkinson's diseases etc.) and protein drugs ineffectiveness. Therefore, a molecule that can inhibit the amyloid fibrillation and potentially clear amyloid fibrils is of great therapeutic value. In this manuscript, we investigated the antiamyloidogenic, fibril disaggregating, as well as cell protective effect of an anti-tuberculosis drug, Capreomycin (CN). Aggregation kinetics data, as monitored by ThT fluorescence, inferred that CN retards the insulin amyloid fibrillation by primarily targeting the fibril elongation step with little effect on lag time. Increasing the dose of CN boosted its inhibitory potency. Strikingly, CN arrested the growth of fibrils when added during the elongation phase, and disaggregated mature insulin fibrils. Our Circular Dichroism (CD) results showed that, although CN is not able to maintain the alpha helical structure of protein during fibrillation, reduces the formation of beta sheet rich structure. Furthermore, Dynamic Light Scattering (DLS) and Transmission Electronic Microscopy (TEM) analysis confirmed that CN treated samples exhibited different size distribution and morphology, respectively. In addition, molecular docking results revealed that CN interacts with insulin through hydrophobic interactions as well as hydrogen bonding, and the Hemolytic assay confirmed the non-hemolytic activity of CN on human RBCs. For future research, this study may assist in the rational designing of molecules against amyloid formation.
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Affiliation(s)
| | - Parvez Alam
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India
| | - Sumit Kumar Chaturvedi
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India
| | - Mohsin Vahid Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India
| | - Saima Nusrat
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India
| | - Sadia Malik
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India
| | - Rizwan Hasan Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India.
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44
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Longhena F, Spano P, Bellucci A. Targeting of Disordered Proteins by Small Molecules in Neurodegenerative Diseases. Handb Exp Pharmacol 2018; 245:85-110. [PMID: 28965171 DOI: 10.1007/164_2017_60] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The formation of protein aggregates and inclusions in the brain and spinal cord is a common neuropathological feature of a number of neurodegenerative diseases including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and many others. These are commonly referred as neurodegenerative proteinopathies or protein-misfolding diseases. The main characteristic of protein aggregates in these disorders is the fact that they are enriched in amyloid fibrils. Since protein aggregation is considered to play a central role for the onset of neurodegenerative proteinopathies, research is ongoing to develop strategies aimed at preventing or removing protein aggregation in the brain of affected patients. Numerous studies have shown that small molecule-based approaches may be potentially the most promising for halting protein aggregation in neurodegenerative diseases. Indeed, several of these compounds have been found to interact with intrinsically disordered proteins and promote their clearing in experimental models. This notwithstanding, at present small molecule inhibitors still awaits achievements for clinical translation. Hopefully, if we determine whether the formation of insoluble inclusions is effectively neurotoxic and find a valid biomarker to assess their protein aggregation-inhibitory activity in the human central nervous system, the use of small molecule inhibitors will be considered as a cure for neurodegenerative protein-misfolding diseases.
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Affiliation(s)
- Francesca Longhena
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa No. 11, Brescia, 25123, Italy
| | - PierFranco Spano
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa No. 11, Brescia, 25123, Italy
| | - Arianna Bellucci
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa No. 11, Brescia, 25123, Italy.
- Laboratory of Personalized and Preventive Medicine, University of Brescia, Brescia, Italy.
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45
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Socias SB, González-Lizárraga F, Avila CL, Vera C, Acuña L, Sepulveda-Diaz JE, Del-Bel E, Raisman-Vozari R, Chehin RN. Exploiting the therapeutic potential of ready-to-use drugs: Repurposing antibiotics against amyloid aggregation in neurodegenerative diseases. Prog Neurobiol 2017; 162:17-36. [PMID: 29241812 DOI: 10.1016/j.pneurobio.2017.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 12/07/2017] [Accepted: 12/07/2017] [Indexed: 01/02/2023]
Abstract
Neurodegenerative diseases are chronic and progressive disorders that affect specific regions of the brain, causing gradual disability and suffering that results in a complete inability of patients to perform daily functions. Amyloid aggregation of specific proteins is the most common biological event that is responsible for neuronal death and neurodegeneration in various neurodegenerative diseases. Therapeutic agents capable of interfering with the abnormal aggregation are required, but traditional drug discovery has fallen short. The exploration of new uses for approved drugs provides a useful alternative to fill the gap between the increasing incidence of neurodegenerative diseases and the long-term assessment of classical drug discovery technologies. Drug re-profiling is currently the quickest possible transition from bench to bedside. In this way, experimental evidence shows that some antibiotic compounds exert neuroprotective action through anti-aggregating activity on disease-associated proteins. The finding that many antibiotics can cross the blood-brain barrier and have been used for several decades without serious toxic effects makes them excellent candidates for therapeutic switching towards neurological disorders. The present review is, to our knowledge, the first extensive evaluation and analysis of the anti-amyloidogenic effect of different antibiotics on well-known disease-associated proteins. In addition, we propose a common structural signature derived from the antiaggregant antibiotic molecules that could be relevant to rational drug discovery.
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Affiliation(s)
- Sergio B Socias
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI, San Miguel de Tucumán, Argentina, Argentina
| | - Florencia González-Lizárraga
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI, San Miguel de Tucumán, Argentina, Argentina
| | - Cesar L Avila
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI, San Miguel de Tucumán, Argentina, Argentina
| | - Cecilia Vera
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI, San Miguel de Tucumán, Argentina, Argentina
| | - Leonardo Acuña
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI, San Miguel de Tucumán, Argentina, Argentina; Sorbonne Universite, UPMC Univ Paris 06, INSERM, CNRS, UM75, U1127, UMR 7225, Institut du Cerveau et de la Moelle Epinière, Paris, France
| | - Julia E Sepulveda-Diaz
- Sorbonne Universite, UPMC Univ Paris 06, INSERM, CNRS, UM75, U1127, UMR 7225, Institut du Cerveau et de la Moelle Epinière, Paris, France
| | - Elaine Del-Bel
- Department of Morphology, Physiology and Stomatology, Faculty of Odontology of Ribeirão Preto, University of São Paulo, Brazil; Center of Interdisciplinary Research on Applied Neurosciences (NAPNA), University of São Paulo, Brazil
| | - Rita Raisman-Vozari
- Sorbonne Universite, UPMC Univ Paris 06, INSERM, CNRS, UM75, U1127, UMR 7225, Institut du Cerveau et de la Moelle Epinière, Paris, France.
| | - Rosana N Chehin
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT, and Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI, San Miguel de Tucumán, Argentina, Argentina.
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46
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Sudhakar S, Santhosh PB, Mani E. Dual Role of Gold Nanorods: Inhibition and Dissolution of Aβ Fibrils Induced by Near IR Laser. ACS Chem Neurosci 2017; 8:2325-2334. [PMID: 28737894 DOI: 10.1021/acschemneuro.7b00238] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Extracellular plaques of amyloid beta (Aβ) fibrils and neurofibrillary tangles are known to be associated with neurological diseases such as Alzheimer's disease. Studies have shown that spherical nanoparticles inhibit the formation of Aβ fibrils by intercepting the nucleation and growth pathways of fibrillation. In this report, gold nanorods (AuNRs) are used to inhibit the formation of Aβ fibrils and the shape-dependent plasmonic properties of AuNRs are exploited to faciliate faster dissolution of mature Aβ fibrils. Negatively charged, lipid (DMPC) stabilized AuNRs inhibit the formation of fibrils due to selective binding to the positevly charged amyloidogenic sequence of Aβ protein. The kinetics of inhibition is characterized by thioflavin T (ThT) fluorescence, transmission electronic microscopy (TEM), atomic force microscopy (AFM), and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). An increase in the aspect ratio of DMPC-AuNR in the range of 2.2-4.2 decreased the fibrils content proportionally. Further, the fibrils content is decreased by increasing the concentration of AuNR for all aspect ratios. As AuNR absorb near-infrared (NIR) light and creates a localized hotspot, NIR laser (800 nm) is applied for 2 min to facilitate the thermal dissolution of mature Aβ fibrils. Majority of Aβ fibrils are disintegrated into smaller fragments after exposure to NIR in the presence of AuNR. Thus, the DMPC-AuNRs exhibit a dual effect: inhibition of fibrillation and NIR laser facilitated dissolution of mature amyloid fibrils. This study essentially provides guidelines to design efficient nanoparticle-based therapeutics for neurodegenerative diseases.
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Affiliation(s)
- Swathi Sudhakar
- Polymer Engineering and Colloid Science
Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai-600 036, India
| | - Poornima Budime Santhosh
- Polymer Engineering and Colloid Science
Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai-600 036, India
| | - Ethayaraja Mani
- Polymer Engineering and Colloid Science
Laboratory, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai-600 036, India
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47
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Protein aggregation: From background to inhibition strategies. Int J Biol Macromol 2017; 103:208-219. [DOI: 10.1016/j.ijbiomac.2017.05.048] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 05/11/2017] [Accepted: 05/12/2017] [Indexed: 01/01/2023]
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48
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Gu H, Li L, Cui C, Zhao Z, Song G. Overexpression of let-7a increases neurotoxicity in a PC12 cell model of Alzheimer's disease via regulating autophagy. Exp Ther Med 2017; 14:3688-3698. [PMID: 29042965 DOI: 10.3892/etm.2017.4977] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 06/16/2017] [Indexed: 12/12/2022] Open
Abstract
Increased deposition of β-amyloid (Aβ) protein is one of the typical characteristics of Alzheimer's disease (AD). Recent evidence has demonstrated that the microRNA let-7 family, which is highly expressed in the central nervous system, participates in the regulation of pathologic processes of AD. In the present study, the effect of let-7a overexpression on Aβ1-40-induced neurotoxicity was evaluated in PC12 and SK-N-SH cells. The results indicated that overexpression of let-7a enhanced the neurotoxicity induced by Aβ1-40 in PC12 and SK-N-SH cells. In addition, the apoptosis induced by Aβ1-40 in PC12 and SK-N-SH cells was increased by let-7a overexpression. Furthermore, Aβ1-40 treatment increased the protein levels of microtubule-associated protein 1A/1B-light chain 3 (LC3) and beclin-1 and increased the LC3 II/I ratio. The mRNA expression levels of beclin-1, autophagy protein 5 (Atg-5) and Atg-7 were also increased by Aβ1-40 treatment in PC12 cells. Let-7a overexpression further upregulated the above autophagy-related markers. Furthermore, the protein level of p62 was increased by Aβ1-40 treatment, and this was further enhanced by let-7a overexpression. Finally, the present results demonstrated that the phosphoinositide-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway was involved in the autophagy regulation by let-7a. In conclusion, the present study demonstrates that the neurotoxicity induced by Aβ1-40 is augmented by let-7a overexpression via regulation of autophagy, and the PI3K/Akt/mTOR signaling pathway also serves a function in this process.
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Affiliation(s)
- Huizi Gu
- First Department of Neurology, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116023, P.R. China
| | - Lan Li
- First Department of Neurology, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116023, P.R. China
| | - Chen Cui
- First Department of Neurology, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116023, P.R. China
| | - Zihui Zhao
- First Department of Neurology, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116023, P.R. China
| | - Guijun Song
- First Department of Neurology, The Second Affiliated Hospital of Dalian Medical University, Dalian, Liaoning 116023, P.R. China
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Ford AH, Almeida OP. Management of Depression in Patients with Dementia: Is Pharmacological Treatment Justified? Drugs Aging 2017; 34:89-95. [PMID: 28074409 DOI: 10.1007/s40266-016-0434-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Depression in the context of dementia is common and contributes to poorer outcomes in individuals and those who care for them. Non-pharmacological treatments are the preferred initial approach to managing these symptoms but data in support of these are scarce. There are a number of pharmacological treatment options available to clinicians but efficacy is uncertain and concern about potential side effects in an aging and vulnerable population needs to be taken into consideration. This review aims to provide a concise overview of pharmacological treatments for depression in dementia. Antidepressants are the mainstay of pharmacological treatment for clinically significant depression in the general population but evidence to support their use in dementia is mixed. Trials of antidepressants should generally be reserved for individuals with depression where the symptoms are distressing and surpass the threshold for major depression. Acetylcholinesterase inhibitors and memantine are effective in the symptomatic treatment of Alzheimer's disease but current evidence does not support their use to treat depressive symptoms in dementia. Similarly, antipsychotics and mood stabilizers have no proven efficacy for depression and the risk of adverse effects seems to outweigh any potential benefit. Pain can be a frequent problem in dementia and may have significant effects on behavior and mood. Preliminary evidence supports a role of adequate analgesia in improving mood in people with dementia.
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Affiliation(s)
- Andrew H Ford
- School of Psychiatry and Clinical Neurosciences (M573), Western Australian Centre for Health and Ageing (M573), Harry Perkins Institute of Medical Research, University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia.
| | - Osvaldo P Almeida
- School of Psychiatry and Clinical Neurosciences (M573), Western Australian Centre for Health and Ageing (M573), Harry Perkins Institute of Medical Research, University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
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50
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Alzheimer's disease as oligomeropathy. Neurochem Int 2017; 119:57-70. [PMID: 28821400 DOI: 10.1016/j.neuint.2017.08.010] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/30/2017] [Accepted: 08/13/2017] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder and is characterized by pathological aggregates of amyloid β-protein (Aβ) and tau protein. On the basis of genetic evidence, biochemical data, and animal models, Aβ has been suggested to be responsible for the pathogenesis of AD (the amyloid hypothesis). Aβ molecules tend to aggregate to form oligomers, protofibrils, and mature fibrils. Although mature fibrils in the final stage have been thought to be the cause of AD pathogenesis, recent studies using synthetic Aβ peptides, a cell culture model, Aβ precursor protein transgenic mice models, and human samples, such as cerebrospinal fluids and postmortem brains of AD patients, suggest that pre-fibrillar forms (oligomers of Aβ) are more deleterious than are extracellular fibril forms. Based on this recent evidence showing that oligomers have a central role in the pathogenesis of AD, the term "oligomeropathy" could be used to define AD and other protein-misfolding diseases. In this review, I discuss recent developments in the "oligomer hypothesis" including our research findings regarding the pathogenesis of AD.
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