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Wang P, Ouyang J, Zhou K, Hu D, Zhang S, Zhang A, Yang Y. Olesoxime protects against cisplatin-induced acute kidney injury by attenuating mitochondrial dysfunction. Biomed J 2024:100730. [PMID: 38643825 DOI: 10.1016/j.bj.2024.100730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 03/22/2024] [Accepted: 04/16/2024] [Indexed: 04/23/2024] Open
Abstract
BACKGROUND Mitochondrial dysfunction is a critical factor in the pathogenesis of acute kidney injury (AKI). Agents that ameliorate mitochondrial dysfunction hold potential for AKI treatment. The objective of this study was to investigate the impact of olesoxime, a novel mitochondrial-targeted agent, on cisplatin-induced AKI. METHODS In vivo, a cisplatin-induced AKI mouse model was established by administering a single intraperitoneal dose of cisplatin (25 mg/kg) to male C57BL/6 mice for 72 hours, followed by gavage of either olesoxime or a control solution. In vitro, human proximal tubular HK2 cells were cultured and subjected to treatments with cisplatin, either in the presence or absence of olesoxime. RESULTS In vivo, our findings demonstrated that olesoxime administration significantly mitigated the nephrotoxic effects of cisplatin in mice, as evidenced by reduced blood urea nitrogen (BUN) and serum creatinine (SCr) levels, improved renal histopathology, and decreased expression of renal tubular injury markers such as kidney injury molecule 1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL). Furthermore, olesoxime administration markedly reduced cisplatin-induced apoptosis, inflammation, and oxidative stress in the kidneys of AKI mice. Additionally, olesoxime treatment effectively restored mitochondrial function in the kidneys of AKI mice. In vitro, our results indicated that olesoxime treatment protected against cisplatin-induced apoptosis and mitochondrial dysfunction in cultured HK2 cells. Notably, cisplatin's anticancer effects were unaffected by olesoxime treatment in human cancer cells. CONCLUSION The results of this study suggest that olesoxime is a viable and efficient therapeutic agent in the treatment of cisplatin-induced acute kidney injury presumably by alleviating mitochondrial dysfunction.
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Affiliation(s)
- Peipei Wang
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Department of Nephrology, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing 210029, China
| | - Jing Ouyang
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Department of Nephrology, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing 210029, China
| | - Kaiqian Zhou
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Department of Nephrology, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing 210029, China
| | - Dandan Hu
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Department of Nephrology, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing 210029, China
| | - Shengnan Zhang
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Department of Nephrology, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing 210029, China
| | - Aihua Zhang
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Department of Nephrology, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing 210029, China.
| | - Yunwen Yang
- Nanjing Key Laboratory of Pediatrics, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Department of Nephrology, Children's Hospital of Nanjing Medical University, Guangzhou Road #72, Nanjing 210008, China; Jiangsu Key Laboratory of Pediatrics, Nanjing Medical University, Nanjing 210029, China.
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Muntoni F, Bertini E, Comi G, Kirschner J, Lusakowska A, Mercuri E, Scoto M, van der Pol WL, Vuillerot C, Burdeska A, El-Khairi M, Fontoura P, Ives J, Gorni K, Reid C, Fuerst-Recktenwald S. Long-term follow-up of patients with type 2 and non-ambulant type 3 spinal muscular atrophy (SMA) treated with olesoxime in the OLEOS trial. Neuromuscul Disord 2020; 30:959-969. [PMID: 33246887 DOI: 10.1016/j.nmd.2020.10.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 10/15/2020] [Accepted: 10/20/2020] [Indexed: 12/11/2022]
Abstract
In a previous Phase 2 study, olesoxime had a favorable safety profile. Although the primary endpoint was not met, analyses suggested that olesoxime might help in the maintenance of motor function in patients with Types 2/3 SMA. This open-label extension study (OLEOS) further characterizes the safety, tolerability and efficacy of olesoxime over longer therapy durations. In OLEOS, no new safety risks were identified. Compared to matched natural history data, patients treated with olesoxime demonstrated small, non-significant changes in motor function over 52 weeks. Motor function scores were stable for 52 weeks but declined over the remainder of the study. The greatest decline in motor function was seen in patients ≤15 years old, and those with Type 2 SMA had faster motor function decline versus those with Type 3 SMA. Previous treatment with olesoxime in the Phase 2 study was not protective of motor function in OLEOS. Respiratory outcomes were stable in patients with Type 3 SMA >15 years old but declined in patients with Type 2 SMA and in patients with Type 3 SMA ≤15 years old. Overall, with no stabilization of functional measures observed over 130 weeks, OLEOS did not support significant benefit of olesoxime in patients with SMA.
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Affiliation(s)
- Francesco Muntoni
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health and Great Ormond Street Hospital for Children, London, UK; NIHR Biomedical Research Centre, UCL Great Ormond Street Institute of Child Health and Great Ormond Street Hospital NHS Trust, London, UK.
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Research Hospital IRCCS, Rome, Italy
| | - Giacomo Comi
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Neurology Unit, I.R.C.C.S. Foundation Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Janbernd Kirschner
- Department of Neuropediatrics and Muscle Disorders, Medical Center-University of Freiburg, Freiburg, Germany; Department of Neuropediatrics, University Hospital Bonn, Bonn, Germany
| | - Anna Lusakowska
- Department of Neurology, Medical University of Warsaw, Warsaw, Poland
| | - Eugenio Mercuri
- Paediatric Neurology and Nemo Center, Catholic University and Policlinico Gemelli, Rome, Italy
| | - Mariacristina Scoto
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health and Great Ormond Street Hospital for Children, London, UK
| | - W Ludo van der Pol
- Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Carole Vuillerot
- Department of Paediatric Physical Medicine and Rehabilitation, Hôpital Femme Mère Enfant, Centre Hospitalier Universitaire de Lyon, France; NeuroMyogene Institute, CNRS UMR 5310, INSERM U1217, Université de Lyon, Lyon, France
| | - Alexander Burdeska
- Pharma Development, Safety, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | | | - Paulo Fontoura
- Neuroscience Product Development, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Jane Ives
- Roche Products Limited, Welwyn Garden City, UK
| | - Ksenija Gorni
- Roche Pharmaceutical Research and Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Carol Reid
- Roche Products Limited, Welwyn Garden City, UK
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Zakyrjanova GF, Gilmutdinov AI, Tsentsevitsky AN, Petrov AM. Olesoxime, a cholesterol-like neuroprotectant restrains synaptic vesicle exocytosis in the mice motor nerve terminals: Possible role of VDACs. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158739. [PMID: 32428575 DOI: 10.1016/j.bbalip.2020.158739] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 05/11/2020] [Accepted: 05/13/2020] [Indexed: 12/13/2022]
Abstract
Olesoxime is a cholesterol-like neuroprotective compound that targets to mitochondrial voltage dependent anion channels (VDACs). VDACs were also found in the plasma membrane and highly expressed in the presynaptic compartment. Here, we studied the effects of olesoxime and VDAC inhibitors on neurotransmission in the mouse neuromuscular junction. Electrophysiological analysis revealed that olesoxime suppressed selectively evoked neurotransmitter release in response to a single stimulus and 20 Hz activity. Also olesoxime decreased the rate of FM1-43 dye loss (an indicator of synaptic vesicle exocytosis) at low frequency stimulation and 20 Hz. Furthermore, an increase in extracellular Cl- enhanced the action of olesoxime on the exocytosis and olesoxime increased intracellular Cl- levels. The effects of olesoxime on the evoked synaptic vesicle exocytosis and [Cl-]i were blocked by membrane-permeable and impermeable VDAC inhibitors. Immunofluorescent labeling pointed on the presence of VDACs on the synaptic membranes. Rotenone-induced mitochondrial dysfunction perturbed the exocytotic release of FM1-43 and cell-permeable VDAC inhibitor (but not olesoxime or impermeable VDAC inhibitor) partially mitigated the rotenone-driven alterations in the FM1-43 unloading and mitochondrial superoxide production. Thus, olesoxime restrains neurotransmission by acting on plasmalemmal VDACs whose activation can limit synaptic vesicle exocytosis probably via increasing anion flux into the nerve terminals.
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Affiliation(s)
- Guzalia F Zakyrjanova
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia; Institute of Neuroscience, Kazan State Medial University, 49 Butlerova Street, Kazan 420012, Russia
| | - Amir I Gilmutdinov
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia
| | - Andrey N Tsentsevitsky
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia
| | - Alexey M Petrov
- Laboratory of Biophysics of Synaptic Processes, Kazan Institute of Biochemistry and Biophysics, Federal Research Center "Kazan Scientific Center of RAS", 2/31 Lobachevsky Street, box 30, Kazan 420111, Russia; Institute of Neuroscience, Kazan State Medial University, 49 Butlerova Street, Kazan 420012, Russia.
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Eckert GP, Eckert SH, Eckmann J, Hagl S, Muller WE, Friedland K. Olesoxime improves cerebral mitochondrial dysfunction and enhances Aβ levels in preclinical models of Alzheimer's disease. Exp Neurol 2020; 329:113286. [PMID: 32199815 DOI: 10.1016/j.expneurol.2020.113286] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 02/15/2020] [Accepted: 03/17/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Approved drugs for Alzheimer's disease (AD) only have a symptomatic effects and do not intervene causally in the course of the disease. Olesoxime (TRO19622) has been tested in AD disease models characterized by improved amyloid precursor protein processing (AβPP) and mitochondrial dysfunction. METHODS Three months old Thy-1-AβPPSL (tg) and wild type mice (wt) received TRO19622 (100 mg/kg b.w.) in supplemented food pellets for 15 weeks (tg TRO19622). Mitochondrial membrane potential (MMP) and adenosine triphosphate (ATP) levels were determined in dissociated brain cells (DBC). Respiration was analyzed in mitochondria isolated from brain tissue. Citrate synthase (CS) activity and beta-amyloid peptide (Aβ1-40) levels were determined in brain tissue. Malondialdehyde (MDA) levels were determined as an indicator for lipid peroxidation. DBC and brain homogenates were additionally stressed with Rotenone and FeCl2, respectively. Mitochondrial respiration and Aβ1-40 levels were also determined in HEK-AβPPsw-cells. RESULTS Treatment of mice did not affect the body weight. TRO19622 was absorbed after oral treatment (plasma levels: 6,2 μg/ml). Mitochondrial respiration was significantly reduced in brains of tg-mice. Subsequently, DBC isolated from brains of tg-mice showed significantly lower MMP but not ATP levels. TRO19622 increased the activity of respiratory chain complexes and reversed complex IV (CIV) activity and MMP. Moreover, DBC isolated from brains of tg TRO19622 mice were protected from Rotenone induced inhibition of complex I activity. TRO19622 also increased the respiratory activity in HEKsw-cells. MDA basal levels were significantly higher in brain homogenates isolated from tg-mice. TRO19622 treatment had no effects on lipid peroxidation. TRO19622 increased cholesterol levels but did not change membrane fluidity of synaptosomal plasma and mitochondrial membranes isolated from brain of mice. TRO19622 significantly increased levels of Aβ1-40 in both, in brains of tg TRO19622 mice and in HEKsw cells. CONCLUSIONS TRO19622 improves mitochondrial dysfunction but enhances Aβ levels in disease models of AD. Further studies must evaluate whether TRO19622 offers benefits at the mitochondrial level despite the increased formation of Aβ, which could be harmful.
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Affiliation(s)
- Gunter P Eckert
- Institute of Nutritional Sciences, Justus-Liebig-University, Giessen, Germany.
| | - Schamim H Eckert
- Institute of Pharmacology, Goethe University, Frankfurt, Germany
| | - Janett Eckmann
- Institute of Pharmacology, Goethe University, Frankfurt, Germany
| | - Stephanie Hagl
- Institute of Pharmacology, Goethe University, Frankfurt, Germany
| | - Walter E Muller
- Institute of Pharmacology, Goethe University, Frankfurt, Germany
| | - Kristina Friedland
- Institute of Pharmacology, Johannes-Gutenberg University, Mainz, Germany
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Weber JJ, Clemensson LE, Schiöth HB, Nguyen HP. Olesoxime in neurodegenerative diseases: Scrutinising a promising drug candidate. Biochem Pharmacol 2019; 168:305-318. [PMID: 31283931 DOI: 10.1016/j.bcp.2019.07.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 07/03/2019] [Indexed: 12/14/2022]
Abstract
Over the last years, the experimental compound olesoxime, a mitochondria-targeting cholesterol derivative, has emerged as a promising drug candidate for neurodegenerative diseases. Numerous preclinical studies have successfully proved olesoxime's neuroprotective properties in cell and animal models of clinical conditions such as amyotrophic lateral sclerosis, Huntington disease, Parkinson disease, peripheral neuropathy and spinal muscular atrophy. The beneficial effects were attributed to olesoxime's potential impact on oxidative stress, mitochondrial permeability transition or cholesterol homoeostasis. Although no significant benefits have been demonstrated in patients of amyotrophic lateral sclerosis, and only the first 12 months of a phase II/III clinical trial showed an improvement in motor symptoms of spinal muscular atrophy, this orphan drug may still offer undiscovered potential in the treatment of neurological diseases. In our earlier preclinical studies, we demonstrated that administration of olesoxime in mouse and rat models of Huntington disease improved psychiatric and molecular phenotypes. Aside from stabilising mitochondrial function, the drug reduced the overactivation of calpains, a class of calcium-dependent proteases entangled in neurodegenerative conditions. This observation may be credited to olesoxime's action on calcium dyshomeostasis, a further hallmark in neurodegeneration, and linked to its targets TSPO and VDAC, two proteins of the outer mitochondrial membrane associated with mitochondrial calcium handling. Further research into the mode of action of olesoxime under pathological conditions, including its effect on neuronal calcium homeostasis, may strengthen the untapped potential of olesoxime or other similar compounds as a therapeutic for neurodegenerative diseases.
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Affiliation(s)
- Jonasz Jeremiasz Weber
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany.
| | | | - Helgi Birgir Schiöth
- Department of Neuroscience, Uppsala University, Uppsala, Sweden; Institute for Translational Medicine and Biotechnology, Sechenov First Moscow State Medical University, Moscow, Russia.
| | - Huu Phuc Nguyen
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany; Department of Human Genetics, Ruhr-University Bochum, Bochum, Germany.
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Kaviani M, Keshtkar S, Azarpira N, Aghdaei MH, Geramizadeh B, Karimi MH, Shamsaeefar A, Motazedian N, Nikeghbalian S, Al-Abdullah IH, Ghahremani MH. Cytoprotective effects of olesoxime on isolated human pancreatic islets in order to attenuate apoptotic pathway. Biomed Pharmacother 2019; 112:108674. [PMID: 30784942 DOI: 10.1016/j.biopha.2019.108674] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 02/06/2019] [Accepted: 02/06/2019] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Islet transplantation is considered as a promising approach in the treatment of diabetes type 1. In this regard, optimal culture of the pancreatic islets is promising in the success of transplantation. In the present study, the effect of olesoxime, as an antiapoptotic substance, was evaluated on human islet culture. EXPERIMENTAL APPROACH The pancreatic islets were isolated by mechanical and enzymatic techniques. After overnight recovery, the islets were treated by different concentrations of olesoxime for 24 and 72 h. Then, they were examined in terms of viability, apoptosis, genes and proteins expression including BAX, BCL2, active caspase-3, and insulin. Moreover, the islets function was evaluated through the glucose-induced insulin and C-peptide secretion assay. KEY RESULTS Our findings showed that the islets increased in apoptosis and the decreased in viability after 72 h; also, insulin and C-peptide secretion reduced. However, in the presence of olesoxime, BAX/BCL2 ratio and the activation of caspase-3 were decreased. Therefore, olesoxime could improve the viability of the islets with the decrease of apoptosis. CONCLUSION The application of olesoxime can reduce the stressful condition for the islets in vitro and subsequently improve their viability and functionality.
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Affiliation(s)
- Maryam Kaviani
- Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Somayeh Keshtkar
- Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Negar Azarpira
- Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
| | | | - Bita Geramizadeh
- Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Alireza Shamsaeefar
- Shiraz Organ Transplant Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Nasrin Motazedian
- Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Saman Nikeghbalian
- Shiraz Organ Transplant Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ismail H Al-Abdullah
- Department of Translational Research and Cellular Therapeutics, Diabetes and Metabolism Research Institute, Beckman Research Institute of City of Hope, Duarte, USA
| | - Mohammad Hossein Ghahremani
- Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran; Department of Pharmacology-Toxicology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
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Kasimov MR, Zakyrjanova GF, Giniatullin AR, Zefirov AL, Petrov AM. Similar oxysterols may lead to opposite effects on synaptic transmission: Olesoxime versus 5α-cholestan-3-one at the frog neuromuscular junction. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:606-16. [PMID: 27102612 DOI: 10.1016/j.bbalip.2016.04.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/17/2016] [Accepted: 04/15/2016] [Indexed: 02/03/2023]
Abstract
Cholesterol oxidation products frequently have a high biological activity. In the present study, we have used microelectrode recording of end plate currents and FM-based optical detection of synaptic vesicle exo-endocytosis to investigate the effects of two structurally similar oxysterols, olesoxime (cholest-4-en-3-one, oxime) and 5ɑ-cholestan-3-one (5ɑCh3), on neurotransmission at the frog neuromuscular junction. Olesoxime is an exogenous, potentially neuroprotective, substance and 5ɑCh3 is an intermediate product in cholesterol metabolism, which is elevated in the case of cerebrotendinous xanthomatosis. We found that olesoxime slightly increased evoked neurotransmitter release in response to a single stimulus and significantly reduced synaptic depression during high frequency activity. The last effect was due to an increase in both the number of synaptic vesicles involved in exo-endocytosis and the rate of synaptic vesicle recycling. In contrast, 5ɑCh3 reduced evoked neurotransmitter release during the low- and high frequency synaptic activities. The depressant action of 5ɑCh3 was associated with a reduction in the number of synaptic vesicles participating in exo- and endocytosis during high frequency stimulation, without a change in rate of the synaptic vesicle recycling. Of note, olesoxime increased the staining of synaptic membranes with the B-subunit of cholera toxin and the formation of fluorescent ganglioside GM1 clusters, and decreased the fluorescence of 22-NBD-cholesterol, while 5ɑCh3 had the opposite effects, suggesting that the two oxysterols have different effects on lipid raft stability. Taken together, these data show that these two structurally similar oxysterols induce marked different changes in neuromuscular transmission which are related with the alteration in synaptic vesicle cycle.
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Affiliation(s)
- M R Kasimov
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - G F Zakyrjanova
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - A R Giniatullin
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - A L Zefirov
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - A M Petrov
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia.
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