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Ammar M, Yaich S, Hakim A, Ghozzi H, Sahnoun Z, Ben Hmida M, Zghal K, Ben Mahmoud L. Tacrolimus trough level and oxidative stress in Tunisian kidney transplanted patients. Ren Fail 2024; 46:2313863. [PMID: 38345031 PMCID: PMC10863538 DOI: 10.1080/0886022x.2024.2313863] [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: 10/25/2023] [Accepted: 01/30/2024] [Indexed: 02/15/2024] Open
Abstract
BACKGROUND The effect of tacrolimus (TAC) on oxidative stress after kidney transplantation (KT) is unclear. This study aimed to evaluate the influence of TAC trough levels of oxidative stress status in Tunisian KT patients during the post-transplantation period (PTP). METHODS A prospective study including 90 KT patients was performed. TAC whole-blood concentrations were measured by the microparticle enzyme immunoassay method and adjusted according to the target range. Plasma levels of oxidants (malondialdehyde (MDA) and advanced oxidation protein products (AOPP)) and antioxidants (ascorbic acid, glutathione (GSH), glutathione peroxidase (GPx), and superoxide dismutase (SOD)) were measured using spectrophotometry. The subjects were subdivided according to PTP into three groups: patients with early, intermediate, and late PT. According to the TAC level, they were subdivided into LL-TAC, NL-TAC, and HL-TAC groups. RESULTS A decrease in MDA levels, SOD activity, and an increase in GSH levels and GPx activity were observed in patients with late PT compared to those with early and intermediate PT (p < 0.05). Patients with LL-TAC had lower MDA levels and higher GSH levels and GPx activity compared with the NL-TAC and HL-TAC groups (p < 0.05). CONCLUSION Our results have shown that in KT patients, despite the recovery of kidney function, the TAC reduced but did not normalize oxidative stress levels in long-term therapy, and the TAC effect significantly depends on the concentration used.
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Affiliation(s)
- Mariam Ammar
- Department of Pharmacology, Faculty of Medicine, University of Sfax, Sfax, Tunisia
- Laboratory of Research of Pharmacology and Toxicology, University of Sfax, Sfax, Tunisia
- Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia
| | - Soumaya Yaich
- Department of Nephrology, Hedi Chaker University Hospital, University of Sfax, Sfax, Tunisia
- Laboratory of Research of Renal Pathology, University of Sfax, Sfax, Tunisia
| | - Ahmed Hakim
- Department of Pharmacology, Faculty of Medicine, University of Sfax, Sfax, Tunisia
- Laboratory of Research of Pharmacology and Toxicology, University of Sfax, Sfax, Tunisia
| | - Hanen Ghozzi
- Department of Pharmacology, Faculty of Medicine, University of Sfax, Sfax, Tunisia
- Laboratory of Research of Pharmacology and Toxicology, University of Sfax, Sfax, Tunisia
| | - Zouheir Sahnoun
- Department of Pharmacology, Faculty of Medicine, University of Sfax, Sfax, Tunisia
- Laboratory of Research of Pharmacology and Toxicology, University of Sfax, Sfax, Tunisia
| | - Mohamed Ben Hmida
- Department of Nephrology, Hedi Chaker University Hospital, University of Sfax, Sfax, Tunisia
- Laboratory of Research of Renal Pathology, University of Sfax, Sfax, Tunisia
| | - Khaled Zghal
- Department of Pharmacology, Faculty of Medicine, University of Sfax, Sfax, Tunisia
- Laboratory of Research of Pharmacology and Toxicology, University of Sfax, Sfax, Tunisia
| | - Lobna Ben Mahmoud
- Department of Pharmacology, Faculty of Medicine, University of Sfax, Sfax, Tunisia
- Laboratory of Research of Pharmacology and Toxicology, University of Sfax, Sfax, Tunisia
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Samuvel DJ, Li L, Krishnasamy Y, Gooz M, Takemoto K, Woster PM, Lemasters JJ, Zhong Z. Mitochondrial depolarization after acute ethanol treatment drives mitophagy in living mice. Autophagy 2022; 18:2671-2685. [PMID: 35293288 PMCID: PMC9629059 DOI: 10.1080/15548627.2022.2046457] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 02/18/2022] [Accepted: 02/22/2022] [Indexed: 12/15/2022] Open
Abstract
Ethanol increases hepatic mitophagy driven by unknown mechanisms. Type 1 mitophagy sequesters polarized mitochondria for nutrient recovery and cytoplasmic remodeling. In Type 2, mitochondrial depolarization (mtDepo) initiates mitophagy to remove the damaged organelles. Previously, we showed that acute ethanol administration produces reversible hepatic mtDepo. Here, we tested the hypothesis that ethanol-induced mtDepo initiates Type 2 mitophagy. GFP-LC3 transgenic mice were gavaged with ethanol (2-6 g/kg) with and without pre-treatment with agents that decrease or increase mtDepo-Alda-1, tacrolimus, or disulfiram. Without ethanol, virtually all hepatocytes contained polarized mitochondria with infrequent autophagic GFP-LC3 puncta visualized by intravital microscopy. At ~4 h after ethanol treatment, mtDepo occurred in an all-or-none fashion within individual hepatocytes, which increased dose dependently. GFP-LC3 puncta increased in parallel, predominantly in hepatocytes with mtDepo. Mitochondrial PINK1 and PRKN/parkin also increased. After covalent labeling of mitochondria with MitoTracker Red (MTR), GFP-LC3 puncta encircled MTR-labeled mitochondria after ethanol treatment, directly demonstrating mitophagy. GFP-LC3 puncta did not associate with fat droplets visualized with BODIPY558/568, indicating that increased autophagy was not due to lipophagy. Before ethanol administration, rhodamine-dextran (RhDex)-labeled lysosomes showed little association with GFP-LC3. After ethanol treatment, TFEB (transcription factor EB) translocated to nuclei, and lysosomal mass increased. Many GFP-LC3 puncta merged with RhDex-labeled lysosomes, showing autophagosomal processing into lysosomes. After ethanol treatment, disulfiram increased, whereas Alda-1 and tacrolimus decreased mtDepo, and mitophagy changed proportionately. In conclusion, mtDepo after acute ethanol treatment induces mitophagic sequestration and subsequent lysosomal processing.Abbreviations : AcAld, acetaldehyde; ADH, alcohol dehydrogenase; ALDH, aldehyde dehydrogenase; ALD, alcoholic liver disease; Alda-1, N-(1,3-benzodioxol-5-ylmethyl)-2,6-dichlorobenzamide; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; GFP, green fluorescent protein; LAMP1, lysosomal-associated membrane protein 1; LMNB1, lamin B1; MAA, malondialdehyde-acetaldehyde adducts; MAP1LC3/LC3, microtubule-associated protein 1 light chain 3; MPT, mitochondrial permeability transition; mtDAMPS, mitochondrial damage-associated molecular patterns; mtDepo, mitochondrial depolarization; mtDNA, mitochondrial DNA; MTR, MitoTracker Red; PI, propidium iodide; PINK1, PTEN induced putative kinase 1; PRKN, parkin; RhDex, rhodamine dextran; TFEB, transcription factor EB; Tg, transgenic; TMRM, tetramethylrhodamine methylester; TOMM20, translocase of outer mitochondrial membrane 20; VDAC, voltage-dependent anion channel.
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Affiliation(s)
- Devadoss J. Samuvel
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Li Li
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Yasodha Krishnasamy
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Monika Gooz
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Kenji Takemoto
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - Patrick M. Woster
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
| | - John J. Lemasters
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
- Department of Biochemistry & Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Zhi Zhong
- Departments of Drug Discovery & Biomedical Science, Medical University of South Carolin, Charleston, SC, USA
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A Potential Route to Reduce Ischemia/Reperfusion Injury in Organ Preservation. Cells 2022; 11:cells11172763. [PMID: 36078175 PMCID: PMC9455584 DOI: 10.3390/cells11172763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/29/2022] [Accepted: 09/01/2022] [Indexed: 11/16/2022] Open
Abstract
The pathophysiological process of ischemia and reperfusion injury (IRI), an inevitable step in organ transplantation, causes important biochemical and structural changes that can result in serious organ damage. IRI is relevant for early graft dysfunction and graft survival. Today, in a global context of organ shortages, most organs come from extended criteria donors (ECDs), which are more sensitive to IRI. The main objective of organ preservation solutions is to protect against IRI through the application of specific, nonphysiological components, under conditions of no blood or oxygen, and then under conditions of metabolic reduction by hypothermia. The composition of hypothermic solutions includes osmotic and oncotic buffering components, and they are intracellular (rich in potassium) or extracellular (rich in sodium). However, above all, they all contain the same type of components intended to protect against IRI, such as glutathione, adenosine and allopurinol. These components have not changed for more than 30 years, even though our knowledge of IRI, and much of the relevant literature, questions their stability or efficacy. In addition, several pharmacological molecules have been the subjects of preclinical studies to optimize this protection. Among them, trimetazidine, tacrolimus and carvedilol have shown the most benefits. In fact, these drugs are already in clinical use, and it is a question of repositioning them for this novel use, without additional risk. This new strategy of including them would allow us to shift from cold storage solutions to cold preservation solutions including multitarget pharmacological components, offering protection against IRI and thus protecting today's more vulnerable organs.
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Mitochondrial biogenesis as a therapeutic target for traumatic and neurodegenerative CNS diseases. Exp Neurol 2020; 329:113309. [PMID: 32289315 DOI: 10.1016/j.expneurol.2020.113309] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 03/31/2020] [Accepted: 04/10/2020] [Indexed: 12/27/2022]
Abstract
Central nervous system (CNS) diseases, both traumatic and neurodegenerative, are characterized by impaired mitochondrial bioenergetics and often disturbed mitochondrial dynamics. The dysregulation observed in these pathologies leads to defective respiratory chain function and reduced ATP production, thereby promoting neuronal death. As such, attenuation of mitochondrial dysfunction through induction of mitochondrial biogenesis (MB) is a promising, though still underexplored, therapeutic strategy. MB is a multifaceted process involving the integration of highly regulated transcriptional events, lipid membrane and protein synthesis/assembly and replication of mtDNA. Several nuclear transcription factors promote the expression of genes involved in oxidative phosphorylation, mitochondrial import and export systems, antioxidant defense and mitochondrial gene transcription. Of these, the nuclear-encoded peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is the most commonly studied and is widely accepted as the 'master regulator' of MB. Several recent preclinical studies document that reestablishment of mitochondrial homeostasis through increased MB results in inhibited injury progression and increased functional recovery. This perspective will briefly review the role of mitochondrial dysfunction in the propagation of CNS diseases, while also describing current research strategies that mediate mitochondrial dysfunction and compounds that induce MB for the treatment of acute and chronic neuropathologies.
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Chen MX, Ward E, Caivano M, Toh S, Searle K, Ramachandran S, Lacroix Y, Ahmed M, Rutter AR. Probing Mitochondrial Permeability Transition Pore Activity in Nucleated Cells and Platelets by High-Throughput Screening Assays Suggests Involvement of Protein Phosphatase 2B in Mitochondrial Dynamics. Assay Drug Dev Technol 2018; 16:445-455. [PMID: 30481043 DOI: 10.1089/adt.2018.872] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Mitochondrial permeability transition pore (mPTP) formation is well documented in isolated mitochondria. However, convincing detection of mPTP in whole cells remains elusive. In this study, we describe a high-throughput assay for Ca2+-activated mPTP opening in platelets using HyperCyt flow cytometry. In addition, we demonstrate that in several nucleated cells, using multiple approaches, the detection of cyclophilin D-dependent mPTP opening is highly challenging. Results with the mitochondrial-targeted Ca2+-sensing green fluorescent protein (mito-Case12) suggest the involvement of protein phosphatase 2B (PP2B; calcineurin) in regulating mitochondrial dynamics. Our results highlight the danger of relying on cyclosporine A alone as a pharmacological tool, and the need for comprehensive studies of mPTP in the cell.
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Affiliation(s)
| | - Emma Ward
- GlaxoSmithKline R&D , Stevenage, United Kingdom
| | | | - Sandy Toh
- GlaxoSmithKline R&D , Stevenage, United Kingdom
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Chung YW, Chung MW, Choi SK, Choi SJ, Choi SJN, Chung SY. Tacrolimus-Induced Apoptosis is Mediated by Endoplasmic Reticulum-derived Calcium-dependent Caspases-3,-12 in Jurkat Cells. Transplant Proc 2018; 50:1172-1177. [PMID: 29731088 DOI: 10.1016/j.transproceed.2018.01.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 01/30/2018] [Indexed: 11/16/2022]
Abstract
Apoptotic signal pathways are delivered to caspase-3, caspase-9, or both in different cells via the death receptor pathway, mitochondrial pathway, or by the endoplasmic reticulum (ER) pathway through initiators of caspase-3, -8, -9, or -12. Tacrolimus (Tac)-induced apoptosis was characterized by nuclear fragmentation and caspase-3 activation. We examined the effect of tacrolimus on ER-derived calcium and caspase-3,-12-mediated apoptosis on Jurkat human T lymphocyte. Tac decreased the viability of Jurkat cells in a dose-dependent manner. Tac also increased continuously intracellular concentration of calcium from 24 hours to 72 hours. We did not find intracellular calcium changes on the treatment of calcium ionorpore (A23187) regardless of 1 nmol/L Tac concentration level. However, calcium adenosine triphosphatase inhibitor (thapsigargin) increased intracellular calcium accumulation and co-treating 1 nmol/L Tac further induced intracellular calcium accumulation. Interestingly, we found that 1 nmol/L Tac treatment induced activation of caspase-12 protease as well as the catalytic activity of caspase-3 but not catalytic activation of caspase-6, -8, and -9 proteases in Jurkat cells. These data advance our understanding of Tac-induced apoptosis is ER-derived calcium and caspases-3,-12- mediated apoptosis in human Jurkat cell line.
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Affiliation(s)
- Y W Chung
- Department of Surgery, Chonnam National University Medical School, Gwangju, Korea
| | - M W Chung
- Department of Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - S K Choi
- Department of Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - S J Choi
- Department of Surgery, Chonnam National University Medical School, Gwangju, Korea
| | - S J N Choi
- Department of Surgery, Chonnam National University Medical School, Gwangju, Korea
| | - S Y Chung
- Department of Surgery, Chonnam National University Medical School, Gwangju, Korea.
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Sompol P, Norris CM. Ca 2+, Astrocyte Activation and Calcineurin/NFAT Signaling in Age-Related Neurodegenerative Diseases. Front Aging Neurosci 2018; 10:199. [PMID: 30038565 PMCID: PMC6046440 DOI: 10.3389/fnagi.2018.00199] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 06/12/2018] [Indexed: 12/12/2022] Open
Abstract
Mounting evidence supports a fundamental role for Ca2+ dysregulation in astrocyte activation. Though the activated astrocyte phenotype is complex, cell-type targeting approaches have revealed a number of detrimental roles of activated astrocytes involving neuroinflammation, release of synaptotoxic factors and loss of glutamate regulation. Work from our lab and others has suggested that the Ca2+/calmodulin dependent protein phosphatase, calcineurin (CN), provides a critical link between Ca2+ dysregulation and the activated astrocyte phenotype. A proteolyzed, hyperactivated form of CN appears at high levels in activated astrocytes in both human tissue and rodent tissue around regions of amyloid and vascular pathology. Similar upregulation of the CN-dependent transcription factor nuclear factor of activated T cells (NFAT4) also appears in activated astrocytes in mouse models of Alzheimer's disease (ADs) and traumatic brain injury (TBI). Major consequences of hyperactivated CN/NFAT4 signaling in astrocytes are neuroinflammation, synapse dysfunction and glutamate dysregulation/excitotoxicity, which will be covered in this review article.
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Affiliation(s)
- Pradoldej Sompol
- Sanders-Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, United States
| | - Christopher M Norris
- Sanders-Brown Center on Aging, University of Kentucky College of Medicine, Lexington, KY, United States.,Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY, United States
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Cai J, Sun Y, Yin Z, Wang D, Shi K, Fu Y, Cao X, Ge Y. Analysis of FK506-mediated functional recovery and neuroprotection in a rat model of spinal cord injury indicates that EGF is modulated in astrocytes. Exp Ther Med 2018; 16:501-510. [PMID: 30116308 PMCID: PMC6090233 DOI: 10.3892/etm.2018.6283] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 12/09/2016] [Indexed: 12/26/2022] Open
Abstract
The present study aimed to evaluate whether the application of tacrolimus (FK506) could improve functional recovery in spinal cord injury (SCI) rat models by activating astrocytes, and to further investigate the underlying mechanisms of this action. Male Sprague-Dawley rats (n=56) were used to establish moderate SCI models, which were induced at the T10 spinal segment by dropping a 10-g weight from a height of 25 mm using a New York University Impactor device. The rats were randomly separated into the FK506 or control group (n=28 per group). Rats were treated with FK506 (0.5 mg/kg) or saline intravenously 30 min after sustaining the injury. Functional recovery was evaluated over 42 days following the injury, and epidermal growth factor (EGF) levels were detected. The astrocytes were treated with FK506 in vitro, and the EGF mRNA and protein expression levels were analyzed using reverse transcription-quantitative polymerase chain reaction and ELISA, respectively. DNA microarray analysis was also performed to evaluate the genes in astrocytes. Rats in the FK506 group had improved locomotor functional recovery compared with those of control group. Furthermore, FK506 upregulated EGF expression of astrocytes both in vivo and in vitro. Subsequent to treatment with FK506-conditioned medium (CM), the length of neuronal cells increased 61.06% on the first day, and increased 56.4% on the third day compared with those of C-CM group. Furthermore, addition of anti-EGF neutralizing antibodies could interrupt the promotion of neurite outgrowth by FK506-CM. The present study indicates that astrocytes have an important role as mediators of FK506-improved spinal cord function recovery, and this partially clarifies the role of cell-cell interaction through modulating EGF in this process.
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Affiliation(s)
- Jun Cai
- Department of Orthopedics, Clinical Medical College of Yangzhou University, Yangzhou, Jiangsu 225001, P.R. China.,Department of Physiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Yu Sun
- Department of Orthopedics, Subei People's Hospital, Yangzhou, Jiangsu 225001, P.R. China
| | - Zaoyang Yin
- Department of Orthopedics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Daode Wang
- Department of Orthopedics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Kun Shi
- Department of Orthopedics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Yuxuan Fu
- Department of Physiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Xiaojian Cao
- Department of Orthopedics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Yingbin Ge
- Department of Physiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
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Transient Oxygen/Glucose Deprivation Causes a Delayed Loss of Mitochondria and Increases Spontaneous Calcium Signaling in Astrocytic Processes. J Neurosci 2017; 36:7109-27. [PMID: 27383588 DOI: 10.1523/jneurosci.4518-15.2016] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 05/24/2016] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED Recently, mitochondria have been localized to astrocytic processes where they shape Ca(2+) signaling; this relationship has not been examined in models of ischemia/reperfusion. We biolistically transfected astrocytes in rat hippocampal slice cultures to facilitate fluorescent confocal microscopy, and subjected these slices to transient oxygen/glucose deprivation (OGD) that causes delayed excitotoxic death of CA1 pyramidal neurons. This insult caused a delayed loss of mitochondria from astrocytic processes and increased colocalization of mitochondria with the autophagosome marker LC3B. The losses of neurons in area CA1 and mitochondria in astrocytic processes were blocked by ionotropic glutamate receptor (iGluR) antagonists, tetrodotoxin, ziconotide (Ca(2+) channel blocker), two inhibitors of reversed Na(+)/Ca(2+) exchange (KB-R7943, YM-244769), or two inhibitors of calcineurin (cyclosporin-A, FK506). The effects of OGD were mimicked by NMDA. The glutamate uptake inhibitor (3S)-3-[[3-[[4-(trifluoromethyl)benzoyl]amino]phenyl]methoxy]-l-aspartate increased neuronal loss after OGD or NMDA, and blocked the loss of astrocytic mitochondria. Exogenous glutamate in the presence of iGluR antagonists caused a loss of mitochondria without a decrease in neurons in area CA1. Using the genetic Ca(2+) indicator Lck-GCaMP-6S, we observed two types of Ca(2+) signals: (1) in the cytoplasm surrounding mitochondria (mitochondrially centered) and (2) traversing the space between mitochondria (extramitochondrial). The spatial spread, kinetics, and frequency of these events were different. The amplitude of both types was doubled and the spread of both types changed by ∼2-fold 24 h after OGD. Together, these data suggest that pathologic activation of glutamate transport and increased astrocytic Ca(2+) through reversed Na(+)/Ca(2+) exchange triggers mitochondrial loss and dramatic increases in Ca(2+) signaling in astrocytic processes. SIGNIFICANCE STATEMENT Astrocytes, the most abundant cell type in the brain, are vital integrators of signaling and metabolism. Each astrocyte consists of many long, thin branches, called processes, which ensheathe vasculature and thousands of synapses. Mitochondria occupy the majority of each process. This occupancy is decreased by ∼50% 24 h after an in vitro model of ischemia/reperfusion injury, due to delayed fragmentation and mitophagy. The mechanism appears to be independent of neuropathology, instead involving an extended period of high glutamate uptake into astrocytes. Our data suggest that mitochondria serve as spatial buffers, and possibly even as a source of calcium signals in astrocytic processes. Loss of mitochondria resulted in drastically altered calcium signaling that could disrupt neurovascular coupling and gliotransmission.
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Ca 2+ ionophores are not suitable for inducing mPTP opening in murine isolated adult cardiac myocytes. Sci Rep 2017; 7:4283. [PMID: 28655872 PMCID: PMC5487341 DOI: 10.1038/s41598-017-04618-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 05/17/2017] [Indexed: 11/08/2022] Open
Abstract
Opening of the mitochondrial permeability transition pore (mPTP) plays a major role in cell death during cardiac ischaemia-reperfusion. Adult isolated rodent cardiomyocytes are valuable cells to study the effect of drugs targeting mPTP. This study investigated whether the use of Ca2+ ionophores (A23187, ionomycin and ETH129) represent a reliable model to study inhibition of mPTP opening in cardiomyocytes. We monitored mPTP opening using the calcein/cobalt fluorescence technique in adult rat and wild type or cyclophilin D (CypD) knock-out mice cardiomyocytes. Cells were either treated with Ca2+ ionophores or subjected to hypoxia followed by reoxygenation. The ionophores induced mPTP-dependent swelling in isolated mitochondria. A23187, but not ionomycin, induced a decrease in calcein fluorescence. This loss could not be inhibited by CypD deletion and was explained by a direct interaction between A23187 and cobalt. ETH129 caused calcein loss, mitochondrial depolarization and cell death but CypD deletion did not alleviate these effects. In the hypoxia-reoxygenation model, CypD deletion delayed both mPTP opening and cell death occurring at the time of reoxygenation. Thus, Ca2+ ionophores are not suitable to induce CypD-dependent mPTP opening in adult murine cardiomyocytes. Hypoxia-reoxygenation conditions appear therefore as the most reliable model to investigate mPTP opening in these cells.
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Heimfarth L, da Silva Ferreira F, Pierozan P, Mingori MR, Moreira JCF, da Rocha JBT, Pessoa-Pureur R. Astrocyte-neuron interaction in diphenyl ditelluride toxicity directed to the cytoskeleton. Toxicology 2017; 379:1-11. [PMID: 28137618 DOI: 10.1016/j.tox.2017.01.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/05/2017] [Accepted: 01/23/2017] [Indexed: 01/04/2023]
Abstract
Diphenylditelluride (PhTe)2 is a neurotoxin that disrupts cytoskeletal homeostasis. We are showing that different concentrations of (PhTe)2 caused hypophosphorylation of glial fibrillary acidic protein (GFAP), vimentin and neurofilament subunits (NFL, NFM and NFH) and altered actin organization in co-cultured astrocytes and neurons from cerebral cortex of rats. These mechanisms were mediated by N-methyl-d-aspartate (NMDA) receptors without participation of either L-type voltage-dependent calcium channels (L-VDCC) or metabotropic glutamate receptors. Upregulated Ca2+ influx downstream of NMDA receptors activated Ca2+-dependent protein phosphatase 2B (PP2B) causing hypophosphorylation of astrocyte and neuron IFs. Immunocytochemistry showed that hypophosphorylated intermediate filaments (IF) failed to disrupt their organization into the cytoskeleton. However, phalloidin-actin-FITC stained cytoskeleton evidenced misregulation of actin distribution, cell spreading and increased stress fibers in astrocytes. βIII tubulin staining showed that neurite meshworks are not altered by (PhTe)2, suggesting greater susceptibility of astrocytes than neurons to (PheTe)2 toxicity. These findings indicate that signals leading to IF hypophosphorylation fail to disrupt the cytoskeletal IF meshwork of interacting astrocytes and neurons in vitro however astrocyte actin network seems more susceptible. Our findings support that intracellular Ca2+ is one of the crucial signals that modulate the action of (PhTe)2 in co-cultured astrocytes and neurons and highlights the cytoskeleton as an end-point of the neurotoxicity of this compound. Cytoskeletal misregulation is associated with cell dysfunction, therefore, the understanding of the molecular mechanisms mediating the neurotoxicity of this compound is a matter of increasing interest since tellurium compounds are increasingly released in the environment.
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Affiliation(s)
- Luana Heimfarth
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, RS, Brazil
| | | | - Paula Pierozan
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, RS, Brazil
| | - Moara Rodrigues Mingori
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, RS, Brazil
| | | | | | - Regina Pessoa-Pureur
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, UFRGS, Porto Alegre, RS, Brazil.
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Parikh S, Karaa A, Goldstein A, Ng YS, Gorman G, Feigenbaum A, Christodoulou J, Haas R, Tarnopolsky M, Cohen BK, Dimmock D, Feyma T, Koenig MK, Mundy H, Niyazov D, Saneto RP, Wainwright MS, Wusthoff C, McFarland R, Scaglia F. Solid organ transplantation in primary mitochondrial disease: Proceed with caution. Mol Genet Metab 2016; 118:178-184. [PMID: 27312126 DOI: 10.1016/j.ymgme.2016.04.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 04/18/2016] [Accepted: 04/18/2016] [Indexed: 01/02/2023]
Abstract
Solid organ transplants are rarely performed in both adult and pediatric patients with primary mitochondrial disease. Poor outcomes have been described in case reports and small case series. It is unclear whether the underlying genetic disease has a significant impact on post-transplant morbidity and mortality. Data were obtained for 35 patients from 17 Mitochondrial Disease Centers across North America, the United Kingdom and Australia. Patient outcomes were noted after liver, kidney or heart transplantation. Excluding patients with POLG-related disease, post-transplant survival approached or met outcomes seen in non-mitochondrial disease transplant patients. The majority of mitochondrial disease patients did not have worsening of their mitochondrial disease within 90-days post-transplant. Post-transplant complications, including organ rejection, were not a common occurrence and were generally treatable. Many patients did not have a mitochondrial disease considered or diagnosed prior to transplantation. In conclusion, patients with mitochondrial disease in this cohort generally tolerated solid-organ transplantation. Such patients may not need to be excluded from transplant solely for their mitochondrial diagnosis; additional caution may be needed for patients with POLG-related disease. Transplant teams should be aware of mitochondrial disease as an etiology for organ-failure and consider appropriate consultation in patients without a known cause of their symptoms.
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Affiliation(s)
- Sumit Parikh
- Neurogenetics & Mitochondrial Disease, Center for Pediatric Neurology, Cleveland Clinic, Cleveland, OH, United States.
| | - Amel Karaa
- Department of Medical Genetics, Massachusetts General Hospital, Boston, MA, United States
| | - Amy Goldstein
- Center for Pediatric Neurology, Children's Hospital of Pittsburgh, Pittsburgh, PA, United States
| | - Yi S Ng
- Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, UK
| | - Grainne Gorman
- Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, UK
| | - Annette Feigenbaum
- Department of Medical Genetics, Rady Children's Hospital, San Diego, CA, United States
| | - John Christodoulou
- Western Sydney Genetics Program, Children's Hospital at Westmead, Sydney and Disciplines of Paediatrics and Child Health and Genetic Medicine, University of Sydney, Sydney, Australia
| | - Richard Haas
- Department of Pediatric Neurology, Rady Children's Hospital, San Diego, CA, United States
| | - Mark Tarnopolsky
- Department of Pediatrics, Division of Neuromuscular and Neurometabolic Disease, McMaster University, Hamilton, ON, Canada
| | - Bruce K Cohen
- Department of Pediatric Neurology, Akron Children's Hospital, Akron, OH, United States
| | - David Dimmock
- Department of Medical Genetics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Tim Feyma
- Department of Pediatric Neurology, Gillette Children's Specialty Healthcare, St. Paul, MN, United States
| | - Mary K Koenig
- Department of Pediatrics, Division of Child & Adolescent Neurology, The University of Texas Medical School at Houston, Houston, TX, United States
| | - Helen Mundy
- Pediatric Metabolism, Evelina London Children's Healthcare, London, UK
| | - Dmitriy Niyazov
- Division of Medical Genetics, Department of Pediatrics, Ochsner Clinic Foundation, New Orleans, LA, United States
| | - Russell P Saneto
- Department of Pediatric Neurology, Seattle Children's Hospital, Seattle, WA, United States
| | - Mark S Wainwright
- Department of Pediatrics, Division of Neurology, Lurie Children's Hospital, Chicago, IL, United States
| | - Courtney Wusthoff
- Department of Pediatric Neurology, Lucile Packard Children's Hospital, Palo Alto, CA, United States
| | - Robert McFarland
- Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, UK
| | - Fernando Scaglia
- Department of Molecular and Human Genetics, Baylor College of Medicine, Baylor, TX, United States
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13
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Doczi J, Torocsik B, Echaniz-Laguna A, Mousson de Camaret B, Starkov A, Starkova N, Gál A, Molnár MJ, Kawamata H, Manfredi G, Adam-Vizi V, Chinopoulos C. Alterations in voltage-sensing of the mitochondrial permeability transition pore in ANT1-deficient cells. Sci Rep 2016; 6:26700. [PMID: 27221760 PMCID: PMC4879635 DOI: 10.1038/srep26700] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2015] [Accepted: 05/09/2016] [Indexed: 01/03/2023] Open
Abstract
The probability of mitochondrial permeability transition (mPT) pore opening is inversely related to the magnitude of the proton electrochemical gradient. The module conferring sensitivity of the pore to this gradient has not been identified. We investigated mPT’s voltage-sensing properties elicited by calcimycin or H2O2 in human fibroblasts exhibiting partial or complete lack of ANT1 and in C2C12 myotubes with knocked-down ANT1 expression. mPT onset was assessed by measuring in situ mitochondrial volume using the ‘thinness ratio’ and the ‘cobalt-calcein’ technique. De-energization hastened calcimycin-induced swelling in control and partially-expressing ANT1 fibroblasts, but not in cells lacking ANT1, despite greater losses of mitochondrial membrane potential. Matrix Ca2+ levels measured by X-rhod-1 or mitochondrially-targeted ratiometric biosensor 4mtD3cpv, or ADP-ATP exchange rates did not differ among cell types. ANT1-null fibroblasts were also resistant to H2O2-induced mitochondrial swelling. Permeabilized C2C12 myotubes with knocked-down ANT1 exhibited higher calcium uptake capacity and voltage-thresholds of mPT opening inferred from cytochrome c release, but intact cells showed no differences in calcimycin-induced onset of mPT, irrespective of energization and ANT1 expression, albeit the number of cells undergoing mPT increased less significantly upon chemically-induced hypoxia than control cells. We conclude that ANT1 confers sensitivity of the pore to the electrochemical gradient.
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Affiliation(s)
- Judit Doczi
- Department of Medical Biochemistry, Semmelweis University MTA-SE Laboratory for Neurobiochemistry, Budapest, 1094, Hungary.,MTA-SE Lendület Neurobiochemistry Research Group, Budapest, Hungary
| | - Beata Torocsik
- Department of Medical Biochemistry, Semmelweis University MTA-SE Laboratory for Neurobiochemistry, Budapest, 1094, Hungary
| | - Andoni Echaniz-Laguna
- Département de Neurologie, Hôpitaux Universitaires, Hôpital de Hautepierre, 67098 Strasbourg cedex, France
| | - Bénédicte Mousson de Camaret
- Service des Maladies Héréditaires du Métabolisme, Centre de Biologie et de Pathologie Est, CHU Lyon, 69677 Bron cedex, France
| | - Anatoly Starkov
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065, USA
| | - Natalia Starkova
- Icahn School of Medicine at Mount Sinai, Department of Hematology and Medical Oncology, New York, NY 10029, USA
| | - Aniko Gál
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, 1083, Hungary
| | - Mária J Molnár
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, 1083, Hungary
| | - Hibiki Kawamata
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065, USA
| | - Giovanni Manfredi
- Feil Family Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10065, USA
| | - Vera Adam-Vizi
- Department of Medical Biochemistry, Semmelweis University MTA-SE Laboratory for Neurobiochemistry, Budapest, 1094, Hungary
| | - Christos Chinopoulos
- Department of Medical Biochemistry, Semmelweis University MTA-SE Laboratory for Neurobiochemistry, Budapest, 1094, Hungary.,MTA-SE Lendület Neurobiochemistry Research Group, Budapest, Hungary
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14
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Fields JA, Overk C, Adame A, Florio J, Mante M, Pineda A, Desplats P, Rockenstein E, Achim C, Masliah E. Neuroprotective effects of the immunomodulatory drug FK506 in a model of HIV1-gp120 neurotoxicity. J Neuroinflammation 2016; 13:120. [PMID: 27220536 PMCID: PMC4879748 DOI: 10.1186/s12974-016-0585-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 05/16/2016] [Indexed: 11/12/2022] Open
Abstract
Background HIV-associated neurocognitive disorders (HAND) continue to be a common morbidity associated with chronic HIV infection. It has been shown that HIV proteins (e.g., gp120) released from infected microglial/macrophage cells can cause neuronal damage by triggering inflammation and oxidative stress, activating aberrant kinase pathways, and by disrupting mitochondrial function and biogenesis. Previous studies have shown that FK506, an immunophilin ligand that modulates inflammation and mitochondrial function and inhibits calcineurin, is capable of rescuing the neurodegenerative pathology in models of Parkinson’s disease, Alzheimer’s disease, and Huntington’s disease. In this context, the main objective of this study was to evaluate if FK506 could rescue the neuronal degeneration and mitochondrial alterations in a transgenic (tg) animal model of HIV1-gp120 neurotoxicity. Methods GFAP-gp120 tg mice were treated with FK506 and analyzed for neuropathology, behavior, mitochondrial markers, and calcium flux by two-photon microscopy. Results We found that FK506 reduced the neuronal cell loss and neuro-inflammation in the gp120 tg mice. Moreover, while vehicle-treated gp120 tg mice displayed damaged mitochondria and increased neuro-inflammatory markers, FK506 rescued the morphological mitochondrial alterations and neuro-inflammation while increasing levels of optic atrophy 1 and mitofusin 1. By two-photon microscopy, calcium levels were not affected in the gp120 tg mice and no effects of FK506 were detected. However, at a functional level, FK506 ameliorated the gp120 tg mice hyperactivity in the open field. Conclusions Together, these results suggest that FK506 might be potentially neuroprotective in patients with HAND by mitigating inflammation and mitochondrial alterations.
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Affiliation(s)
- Jerel A Fields
- Department of Pathology, University of California San Diego, La Jolla, CA, USA
| | - Cassia Overk
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Anthony Adame
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Jazmin Florio
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Michael Mante
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Andrea Pineda
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Paula Desplats
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Edward Rockenstein
- Department of Neurosciences, University of California San Diego, La Jolla, CA, USA
| | - Cristian Achim
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - Eliezer Masliah
- Department of Pathology, University of California San Diego, La Jolla, CA, USA. .,Department of Neurosciences, University of California San Diego, La Jolla, CA, USA.
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15
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Ferjani H, Achour A, Bacha H, Abid S. Tacrolimus and mycophenolate mofetil associations. Hum Exp Toxicol 2015; 34:1119-32. [DOI: 10.1177/0960327115569812] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Gastrointestinal risk factors after organ transplantation are prevalent, due to the chronic use of immunosuppressant. The immunosuppressive drugs such as tacrolimus/mycophenolate mofetil (TAC/MMF) association are the most commonly used therapy. TAC and MMF have been implicated in gastrotoxicity, but their direct effects, alone and combined, on intestinal cells are not completely elucidated. This study investigated the effect of TAC and MMF alone and combined on human colon carcinoma cells. Our results demonstrated that TAC and MMF individually inhibit clearly cells proliferation, enhanced free radicals, lipid peroxidation production, induced DNA lesions and reduced mitochondrial membrane potential. In this study, we also showed that the two molecules TAC and MMF combined at high concentrations amplified the cell damage. Furthermore, the TAC (5 µM) prevented cell death induced by MMF (half maximal inhibitory concentration (IC50)). Also, MMF (50 µM) induced cytoprotection in HCT116 cells against TAC (IC50) toxicity. Our findings provide additional evidence that oxidative damage is the major contribution of TAC and MMF combined toxicities. In fact, MMF and TAC exert a gastroprotective effect by modulating reactive oxygen species production. These data underscore the pleiotropic effect of TAC and MMF on HCT116 cells that play a preventive and critical role on intestinal function.
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Affiliation(s)
- H Ferjani
- Laboratory of Research on Biologically Compatible Compounds, Faculty of Dentistry, Monastir, Tunisia
| | - A Achour
- Department of Nephrology, Dialysis and Transplant, University Hospital of Sahloul, Sousse, Tunisia
| | - H Bacha
- Laboratory of Research on Biologically Compatible Compounds, Faculty of Dentistry, Monastir, Tunisia
| | - S Abid
- Laboratory of Research on Biologically Compatible Compounds, Faculty of Dentistry, Monastir, Tunisia
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16
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Javadov S. Letter to the editor: "cyclosporin A in left ventricular remodeling after myocardial infarction". Am J Physiol Heart Circ Physiol 2014; 306:H777. [PMID: 24583825 DOI: 10.1152/ajpheart.00961.2013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Sabzali Javadov
- Department of Physiology, School of Medicine, University of Puerto Rico, San Juan, Puerto Rico
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17
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Ouyang YB, Xu L, Liu S, Giffard RG. Role of Astrocytes in Delayed Neuronal Death: GLT-1 and its Novel Regulation by MicroRNAs. ADVANCES IN NEUROBIOLOGY 2014; 11:171-88. [PMID: 25236729 DOI: 10.1007/978-3-319-08894-5_9] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Astrocytes have been shown to protect neurons from delayed neuronal death and increase their survival in cerebral ischemia. One of the main mechanisms of astrocyte protection is rapid removal of excess glutamate from synaptic sites by astrocytic plasma membrane glutamate transporters such as GLT-1/EAAT-2, reducing excitotoxicity. Astrocytic mitochondrial function is essential for normal GLT-1 function. Manipulating astrocytic mitochondrial and GLT-1 function is thus an important strategy to enhance neuronal survival and improve outcome following cerebral ischemia. Increasing evidence supports the involvement of microRNAs (miRNA), some of them being astrocyte-enriched, in the regulation of cerebral ischemia. This chapter will first update the information about astrocytes, GLT-1, astrocytic mitochondria, and delayed neuronal death. Then we will focus on two recently reported astrocyte-enriched miRNAs (miR-181 and miR-29 families), their effects on astrocytic mitochondria and GLT-1 as well as on outcome after cerebral ischemia.
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Affiliation(s)
- Yi-Bing Ouyang
- Department of Anesthesia, Stanford University School of Medicine, 300 Pasteur Drive, S272A and S290, Stanford, CA, 94305-5117, USA,
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18
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Quintanilla RA, Jin YN, von Bernhardi R, Johnson GVW. Mitochondrial permeability transition pore induces mitochondria injury in Huntington disease. Mol Neurodegener 2013; 8:45. [PMID: 24330821 PMCID: PMC3878840 DOI: 10.1186/1750-1326-8-45] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 12/02/2013] [Indexed: 12/13/2022] Open
Abstract
Background Mitochondrial impairment has been implicated in the pathogenesis of Huntington’s disease (HD). However, how mutant huntingtin impairs mitochondrial function and thus contributes to HD has not been fully elucidated. In this study, we used striatal cells expressing wild type (STHdhQ7/Q7) or mutant (STHdhQ111/Q111) huntingtin protein, and cortical neurons expressing the exon 1 of the huntingtin protein with physiological or pathological polyglutamine domains, to examine the interrelationship among specific mitochondrial functions. Results Depolarization induced by KCl resulted in similar changes in calcium levels without compromising mitochondrial function, both in wild type and mutant cells. However, treatment of mutant cells with thapsigargin (a SERCA antagonist that raises cytosolic calcium levels), resulted in a pronounced decrease in mitochondrial calcium uptake, increased production of reactive oxygen species (ROS), mitochondrial depolarization and fragmentation, and cell viability loss. The mitochondrial dysfunction in mutant cells was also observed in cortical neurons expressing exon 1 of the huntingtin protein with 104 Gln residues (Q104-GFP) when they were exposed to calcium stress. In addition, calcium overload induced opening of the mitochondrial permeability transition pore (mPTP) in mutant striatal cells. The mitochondrial impairment observed in mutant cells and cortical neurons expressing Q104-GFP was prevented by pre-treatment with cyclosporine A (CsA) but not by FK506 (an inhibitor of calcineurin), indicating a potential role for mPTP opening in the mitochondrial dysfunction induced by calcium stress in mutant huntingtin cells. Conclusions Expression of mutant huntingtin alters mitochondrial and cell viability through mPTP opening in striatal cells and cortical neurons.
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Affiliation(s)
- Rodrigo A Quintanilla
- Department of Anesthesiology, University of Rochester Medical Center, 601 Elmwood Ave, Box 604 (for courier: Rm 4-6314), Rochester, NY 14642, USA.
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19
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Morphological Diversity of Mitochondria in Cultured Astrocyte, HeLa, COS7 Cells under High Voltage Electron Microscopy. Appl Microsc 2013. [DOI: 10.9729/am.2013.43.3.117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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