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A Comparative Analysis of In Vitro Toxicity of Synthetic Zeolites on IMR-90 Human Lung Fibroblast Cells. Molecules 2021; 26:molecules26113194. [PMID: 34073510 PMCID: PMC8198335 DOI: 10.3390/molecules26113194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/23/2021] [Accepted: 05/24/2021] [Indexed: 11/16/2022] Open
Abstract
Broad industrial application of zeolites increases the opportunity of inhalation. However, the potential impact of different types and compositions of zeolite on cytotoxicity is still unknown. Four types of synthetic zeolites have been prepared for assessing the effect on lung fibroblast: two zeolite L (LTL-R and LTL-D), ZSM-5 (MFI-S), and faujasite (FAU-S). The cytotoxicity of zeolites on human lung fibroblast (IMR-90) was assessed using WST1 cell proliferation assay, mitochondrial function, membrane leakage of lactate dehydrogenase, reduced glutathione levels, and mitochondrial membrane potential were assessed under control. Intracellular changes were examined using transmission electron microscopy (TEM). Toxicity-related gene expressions were evaluated by PCR array. The result showed significantly higher toxicity in IMR-90 cells with FAU-S than LTL-R, LTL-D and MFI-S exposure. TEM showed FAU-S, spheroidal zeolite with a low Si/Al ratio, was readily internalized forming numerous phagosomes in IMR-90 cells, while the largest and disc-shaped zeolites showed the lowest toxicity and were located in submembranous phagosomes in IMR-90 cells. Differential expression of TNF related genes was detected using PCR arrays and confirmed using qRT-PCR analysis of selected genes. Collectively, the exposure of different zeolites shows different toxicity on IMR-90 cells.
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Synthesis and anticancer activity of new tetrahydroquinoline hybrid derivatives tethered to isoxazoline moiety. Med Chem Res 2020. [DOI: 10.1007/s00044-020-02513-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Cell line-dependent increase in cellular quercetin accumulation upon stress induced by valinomycin and lipopolysaccharide, but not by TNF-α. Food Res Int 2019; 125:108596. [DOI: 10.1016/j.foodres.2019.108596] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 07/09/2019] [Accepted: 07/28/2019] [Indexed: 11/21/2022]
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Fahanik-Babaei J, Shayanfar F, Khodaee N, Saghiri R, Eliassi A. Electro-pharmacological profiles of two brain mitoplast anion channels: Inferences from single channel recording. EXCLI JOURNAL 2017; 16:531-545. [PMID: 28694756 PMCID: PMC5491910 DOI: 10.17179/excli2016-808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 03/21/2017] [Indexed: 11/29/2022]
Abstract
We have characterized the conduction and blocking properties of two different chloride channels from brain mitochondrial inner membranes after incorporation into planar lipid bilayers. Our experiments revealed the existence of channels with a mean conductance of 158 ± 7 and 301 ± 8 pS in asymmetrical 200 mM cis/50 mM trans KCl solutions. We determined that the channels were ten times more permeable for Cl− than for K+, calculated from the reversal potential using the Goldman-Hodgkin-Katz equation. The channels were bell-shaped voltage dependent, with maximum open probability 0.9 at ± 20 mV. Two mitochondrial chloride channels were blocked after the addition of 10 µM DIDS. In addition, 158 pS chloride channel was blocked by 300 nM NPPB, acidic pH and 2.5 mM ATP, whereas the 301 pS chloride channel was blocked by 600 µM NPPB but not by acidic pH or ATP. Gating and conducting behaviors of these channels were unaffected by Ca2+. These results demonstrate that the 158 pS anion channel present in brain mitochondrial inner membrane, is probably identical to IMAC and 301 pS Cl channel displays different properties than those classically described for mitochondrial anion channels.
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Affiliation(s)
- Javad Fahanik-Babaei
- Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Farzad Shayanfar
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Naser Khodaee
- Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Faculty of Paramedical Sciences, AJA University of Medical Sciences, Tehran, Iran
| | - Reza Saghiri
- Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran
| | - Afsaneh Eliassi
- Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.,Department of Physiology, Medical School, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Al Maruf A, O'Brien PJ, Naserzadeh P, Fathian R, Salimi A, Pourahmad J. Methotrexate induced mitochondrial injury and cytochrome c release in rat liver hepatocytes. Drug Chem Toxicol 2017; 41:51-61. [PMID: 28298149 DOI: 10.1080/01480545.2017.1289221] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Methotrexate (MTX) is a folic acid antagonist that is widely used to treat a variety of diseases. One of the most serious side effects of MTX therapy is hepatotoxicity. The potential molecular cytotoxic mechanisms of MTX toward isolated rat hepatocytes were investigated using Accelerated Cytotoxicity Mechanism Screening (ACMS) techniques. A concentration and time dependent increase in cytotoxicity and reactive oxygen species (ROS) formation and a decrease in mitochondrial membrane potential (MMP) were observed with MTX. Furthermore, a significant increase in MTX (300 μM)-induced cytotoxicity and ROS formation were observed when glutathione (GSH)-depleted hepatocytes were used whereas addition of N-acetylcysteine (a GSH precursor) decreased cytotoxicity. Catalase inactivation also increased MTX-induced cytotoxicity, while the direct addition of catalase to the hepatocytes decreased cytotoxicity. MTX treatment in isolated rat mitochondria caused swelling and significantly decreased adenosine triphosphate (ATP) and GSH content, and cytochrome c release. Potent antioxidants such as mesna, resveratrol and Trolox decreased MTX-induced cytotoxicity and ROS formation and increased MMP. This study suggests that MTX-induced cytotoxicity caused by ROS formation and GSH oxidation leads to oxidative stress and mitochondrial injury in rat hepatocytes.
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Affiliation(s)
- Abdullah Al Maruf
- a Department of Pharmacology & Toxicology, University of Toronto, Toronto, Canada
| | - Peter J O'Brien
- a Department of Pharmacology & Toxicology, University of Toronto, Toronto, Canada.,b Faculty of Pharmacy , University of Toronto , Toronto , Canada
| | - Parvaneh Naserzadeh
- c Faculty of Pharmacy , Shahid Beheshti University of Medical Sciences , Tehran , Iran
| | - Rozhina Fathian
- c Faculty of Pharmacy , Shahid Beheshti University of Medical Sciences , Tehran , Iran
| | - Ahmad Salimi
- d Department of Pharmacology and Toxicology , School of Pharmacy, Ardabil University of Medical Science , Ardabil , Iran
| | - Jalal Pourahmad
- c Faculty of Pharmacy , Shahid Beheshti University of Medical Sciences , Tehran , Iran
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Persona K, Polus A, Góralska J, Gruca A, Dembińska-Kieć A, Piekoszewski W. An In Vitro Study of the Neurotoxic Effects of N-Benzylpiperazine: A Designer Drug of Abuse. Neurotox Res 2016; 29:558-68. [PMID: 26861955 PMCID: PMC4820481 DOI: 10.1007/s12640-016-9604-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 01/11/2016] [Accepted: 01/27/2016] [Indexed: 01/26/2023]
Abstract
Recently, the number of new psychoactive substances has significantly increased. Despite the systematic introduction of prohibition in trade of medicinal products which mimic the effects of illegal drugs, the problem concerning this group of drugs is still important although knowledge about the mechanism of action of those types of substances is scarce. This study aimed to follow the neurotoxic effect of N-benzylpiperazine (BZP), the central nervous system psychostimulant, using the human cancer LN-18 cell model. The statistically significant elevation of LDH levels, increased mitochondrial membrane potential, decreased ATP and increased ROS production, increased levels of DNA damage marker (8-OHdG) and activation of caspases: -3 and -9 confirmed by Real-Time PCR imply the activation of mitochondrial proapoptotic pathways induced by BZP after 24 h incubation. This study is a novel, preliminary attempt to explain the toxicity of one of the most popular designer drug of abuse at the cellular level.
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Affiliation(s)
- Karolina Persona
- Department of Analytical Chemistry, Faculty of Chemistry, Jagiellonian University in Krakow, Ingardena 3, 30-060, Kraków, Poland
| | - Anna Polus
- Department of Clinical Biochemistry, Jagiellonian University in Krakow - Medical College, Kraków, Poland
| | - Joanna Góralska
- Department of Clinical Biochemistry, Jagiellonian University in Krakow - Medical College, Kraków, Poland
| | - Anna Gruca
- Department of Clinical Biochemistry, Jagiellonian University in Krakow - Medical College, Kraków, Poland
| | - Aldona Dembińska-Kieć
- Department of Clinical Biochemistry, Jagiellonian University in Krakow - Medical College, Kraków, Poland
| | - Wojciech Piekoszewski
- Department of Analytical Chemistry, Faculty of Chemistry, Jagiellonian University in Krakow, Ingardena 3, 30-060, Kraków, Poland.
- School of Biomedicine, Far Eastern Federal University, Vladivostok, Russia.
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Takahashi R, Ichikawa H, Kanda K. Novel multiple assessment of hepatocellular drug disposition in a single packaged procedure. Drug Metab Pharmacokinet 2016; 31:167-71. [PMID: 26993380 DOI: 10.1016/j.dmpk.2015.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Revised: 12/10/2015] [Accepted: 12/12/2015] [Indexed: 11/30/2022]
Abstract
UNLABELLED Better prediction of drug disposition prior to the clinical trial is critical for the efficient development of new drugs. The purpose of this study is to develop a novel multiple assessment methodology of hepatocellular drug disposition from drug uptake to efflux including biliary and basolateral excretion, in a single packaged procedure. We started a sandwich culture using rat primary hepatocytes. After five days culture, the hepatocytes were incubated with a dosing solution including CDF or Rhodamine 123. Three distinct sequences were then performed in parallel: disrupting and maintaining the tight junctions comprising a bile canalicular network at 37 °C, and maintaining the network at 4 °C. Supernatant fractions were collected from each sequence, and followed by the cell lysate collection. The disposition rates of basolateral efflux by diffusion, by transporter-mediation, biliary excretion, and residual cellular fraction of CDF and Rhodamine 123 were 38.2% and 11.0%, 26.6% and 12.1%, 18.6% and 4.9%, and, 16.7% and 72.0%, respectively. CDF was likely to excrete extracellularly whereas Rhodamine 123 tended to remain intracellularly. CDF showed a relatively higher biliary excretion rate than Rhodamine 123. This novel protocol may contribute to improve the predictability of pharmacokinetics eventually in human, and streamline new drug development. CHEMICAL COMPOUNDS 5(6)-Carboxy-2',7'-dichlorofluoroscein (PubChem CID: 132525); Rhodamine 123 (PubChem CID: 65217).
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Affiliation(s)
- Ryosuke Takahashi
- Center for Technology Innovation - Healthcare, Hitachi, Ltd., 2520 Hatoyama, Saitama 350-0395, Japan.
| | - Hisashi Ichikawa
- Center for Technology Innovation - Healthcare, Hitachi, Ltd., 2520 Hatoyama, Saitama 350-0395, Japan
| | - Katsuhiro Kanda
- Science Systems Design Div., Hitachi High-Technologies Corporation, 882, Ichige, Hitachinaka, Ibaraki 312-8504, Japan.
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Cao WJ, Wu K, Wang C, Wan DM. Polydatin-induced cell apoptosis and cell cycle arrest are potentiated by Janus kinase 2 inhibition in leukemia cells. Mol Med Rep 2016; 13:3297-302. [PMID: 26934953 DOI: 10.3892/mmr.2016.4909] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Accepted: 11/10/2015] [Indexed: 11/05/2022] Open
Abstract
Polydatin (PD), a natural precursor of resveratrol, has a variety of biological activities, including anti‑tumor effects. However, the underlying molecular mechanisms of the anti-cancer activity of PD has not been fully elucidated. The present study demonstrated that PD significantly inhibited the proliferation of the MOLT-4 leukemia cell line in a dose‑ and time-dependent manner by using Cell Counting Kit‑8 assay. PD also dose-dependently increased the apoptotic rate and caused cell cycle arrest in S phase in MOLT‑4 cells, as revealed by flow cytometry. In addition, PD dose-dependently decreased the mitochondrial membrane potential and led to the generation of reactive oxygen species in MOLT-4 cells. Western blot analysis revealed that the expression of anti‑apoptotic protein B-cell lymphoma 2 (Bcl-2) was decreased, whereas that of pro‑apoptotic protein Bcl‑2‑associated X was increased by PD. Furthermore, the expression of two cell cycle regulatory proteins, cyclin D1 and cyclin B1, was suppressed by PD. Of note, the pro‑apoptotic and cell cycle‑inhibitory effects of PD were potentiated by Janus kinase 2 (JAK2) inhibition. In conclusion, the results of the present study strongly suggested that PD is a promising therapeutic compound for the treatment of leukemia, particularly in combination with JAK inhibitors.
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Affiliation(s)
- Wei-Jie Cao
- Department of Hematology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Ke Wu
- Department of Endodontics, The Fourth Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Chong Wang
- Department of Hematology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
| | - Ding-Ming Wan
- Department of Hematology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052, P.R. China
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Segura-Aguilar J, Kostrzewa RM. Neurotoxin mechanisms and processes relevant to Parkinson's disease: an update. Neurotox Res 2015; 27:328-54. [PMID: 25631236 DOI: 10.1007/s12640-015-9519-y] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 01/13/2015] [Accepted: 01/13/2015] [Indexed: 12/14/2022]
Abstract
The molecular mechanism responsible for degenerative process in the nigrostriatal dopaminergic system in Parkinson's disease (PD) remains unknown. One major advance in this field has been the discovery of several genes associated to familial PD, including alpha synuclein, parkin, LRRK2, etc., thereby providing important insight toward basic research approaches. There is an consensus in neurodegenerative research that mitochon dria dysfunction, protein degradation dysfunction, aggregation of alpha synuclein to neurotoxic oligomers, oxidative and endoplasmic reticulum stress, and neuroinflammation are involved in degeneration of the neuromelanin-containing dopaminergic neurons that are lost in the disease. An update of the mechanisms relating to neurotoxins that are used to produce preclinical models of Parkinson´s disease is presented. 6-Hydroxydopamine, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and rotenone have been the most wisely used neurotoxins to delve into mechanisms involved in the loss of dopaminergic neurons containing neuromelanin. Neurotoxins generated from dopamine oxidation during neuromelanin formation are likewise reviewed, as this pathway replicates neurotoxin-induced cellular oxidative stress, inactivation of key proteins related to mitochondria and protein degradation dysfunction, and formation of neurotoxic aggregates of alpha synuclein. This survey of neurotoxin modeling-highlighting newer technologies and implicating a variety of processes and pathways related to mechanisms attending PD-is focused on research studies from 2012 to 2014.
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Affiliation(s)
- Juan Segura-Aguilar
- Molecular and Clinical Pharmacology, ICBM, Faculty of Medicine, University of Chile, Independencia 1027, Casilla, 70000, Santiago 7, Chile,
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Polyoxometalates as antitumor agents: Bioactivity of a new polyoxometalate with copper on a human osteosarcoma model. Chem Biol Interact 2014; 222:87-96. [DOI: 10.1016/j.cbi.2014.10.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 10/08/2014] [Accepted: 10/10/2014] [Indexed: 11/19/2022]
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Wang J, Zhu S, Wang H, He J, Zhang Y, Adilijiang A, Zhang H, Hartle K, Guo H, Kong J, Huang Q, Li XM. Astrocyte-dependent protective effect of quetiapine on GABAergic neuron is associated with the prevention of anxiety-like behaviors in aging mice after long-term treatment. J Neurochem 2014; 130:780-9. [PMID: 24862291 DOI: 10.1111/jnc.12771] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 04/26/2014] [Accepted: 05/22/2014] [Indexed: 01/03/2023]
Abstract
Previous studies have demonstrated that quetiapine (QTP) may have neuroprotective properties; however, the underlying mechanisms have not been fully elucidated. In this study, we identified a novel mechanism by which QTP increased the synthesis of ATP in astrocytes and protected GABAergic neurons from aging-induced death. In 12-month-old mice, QTP significantly improved cell number of GABAegic neurons in the cortex and ameliorated anxiety-like behaviors compared to control group. Complimentary in vitro studies showed that QTP had no direct effect on the survival of aging GABAergic neurons in culture. Astrocyte-conditioned medium (ACM) pretreated with QTP (ACMQTP) for 24 h effectively protected GABAergic neurons against aging-induced spontaneous cell death. It was also found that QTP boosted the synthesis of ATP from cultured astrocytes after 24 h of treatment, which might be responsible for the protective effects on neurons. Consistent with the above findings, a Rhodamine 123 test showed that ACMQTP, not QTP itself, was able to prevent the decrease in mitochondrial membrane potential in the aging neurons. For the first time, our study has provided evidence that astrocytes may be the conduit through which QTP is able to exert its neuroprotective effects on GABAergic neurons. The neuroprotective properties of quetiapine (QTP) have not been fully understood. Here, we identify a novel mechanism by which QTP increases the synthesis of ATP in astrocytes and protects GABAergic neurons from aging-induced death in a primary cell culture model. In 12-month-old mice, QTP significantly improves cell number of GABAegic neurons and ameliorates anxiety-like behaviors. Our study indicates that astrocytes may be the conduit through which QTP exerts its neuroprotective effects on GABAergic neurons.
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Affiliation(s)
- Junhui Wang
- Mental Health Center, Shantou University, Shantou, Guangdong, China; Department of Psychiatry, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
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ROS generated by CYP450, especially CYP2E1, mediate mitochondrial dysfunction induced by tetrandrine in rat hepatocytes. Acta Pharmacol Sin 2013; 34:1229-36. [PMID: 23892269 DOI: 10.1038/aps.2013.62] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 04/22/2013] [Indexed: 11/08/2022] Open
Abstract
AIM Tetrandrine, an alkaloid with a remarkable pharmacological profile, induces oxidative stress and mitochondrial dysfunction in hepatocytes; however, mitochondria are not the direct target of tetrandrine, which prompts us to elucidate the role of oxidative stress in tetrandrine-induced mitochondrial dysfunction and the sources of oxidative stress. METHODS Rat primary hepatocytes were isolated by two-step collagenase perfusion. Mitochondrial function was evaluated by analyzing ATP content, mitochondrial membrane potential (MMP) and the mitochondrial permeability transition. The oxidative stress was evaluated by examining changes in the levels of reactive oxygen species (ROS) and glutathione (GSH). RESULTS ROS scavengers largely attenuated the cytotoxicity induced by tetrandrine in rat hepatocytes, indicating the important role of ROS in the hepatotoxicity of tetrandrine. Of the multiple ROS inhibitors that were tested, only inhibitors of CYP450 (SKF-525A and others) reduced the ROS levels and ameliorated the depletion of GSH. Mitochondrial function assays showed that the mitochondrial permeability transition (MPT) induced by tetrandrine was inhibited by SKF-525A and vitamin C (VC), both of which also rescued the depletion of ATP levels and the mitochondrial membrane potential. Upon inhibiting specific CYP450 isoforms, we observed that the inhibitors of CYP2D, CYP2C, and CYP2E1 attenuated the ATP depletion that occurred following tetrandrine exposure, whereas the inhibitors of CYP2D and CYP2E1 reduced the ROS induced by tetrandrine. Overexpression of CYP2E1 enhanced the tetrandrine-induced cytotoxicity. CONCLUSION We demonstrated that CYP450 plays an important role in the mitochondrial dysfunction induced by the administration of tetrandrine. ROS generated by CYP450, especially CYP2E1, may contribute to the mitochondrial dysfunction induced by tetrandrine.
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Du Q, Bian XL, Xu XL, Zhu B, Yu B, Zhai Q. Role of mitochondrial permeability transition in human hepatocellular carcinoma Hep-G2 cell death induced by rhein. Fitoterapia 2013; 91:68-73. [PMID: 23994628 DOI: 10.1016/j.fitote.2013.08.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 08/09/2013] [Accepted: 08/10/2013] [Indexed: 11/28/2022]
Abstract
Rhein, a compound found as a glucoside in the root of rhubarb, is currently a subject of interest for its antitumor properties. The apoptosis of tumor cell lines induced by rhein was observed, and the involvement of mitochondria was established; however, the role of mitochondrial permeability transition (MPT) remains unknown. Here we report that MPT plays an important role in the apoptosis of human hepatocellular carcinoma Hep-G2 cells induced by rhein. After adding rhein to the isolated hepatic mitochondria, swelling effects and the leakage of Ca(2+) were observed. These alterations were suppressed by cyclosporin A (CsA), an MPT inhibitor. Furthermore, in Hep-G2 cells, the decrease of ATP production, the loss of mitochondrial transmembrane potential (MTP), the release of cytochrome c (Cyto c), and the activation of caspase 3 were also observed. These toxic effects of rhein can also be attenuated by CsA as well. Moreover, TUNEL assay confirmed that in the presence of CsA, rhein-induced apoptosis was largely inhibited. These results suggest that MPT plays a critical role in the pathogenesis of Hep-G2 cell injury induced by rhein, and imply that MPT may contribute to the anti-cancer activity of rhein.
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Affiliation(s)
- Qiong Du
- Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xiao-Lan Bian
- Department of Pharmacy, Luwan Branch of Rui-Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China; Department of Pharmacy, Rui-Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiao-Le Xu
- Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Bin Zhu
- Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Bo Yu
- Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
| | - Qing Zhai
- Department of Pharmacy, Fudan University Shanghai Cancer Center, 270 Dong-An Road, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China.
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Cardioprotective effect of Urtica parviflora leaf extract against doxorubicin-induced cardiotoxicity in rats. Chin J Nat Med 2013. [DOI: 10.1016/s1875-5364(13)60005-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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15
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Maioli MA, Alves LC, Perandin D, Garcia AF, Pereira FTV, Mingatto FE. Cytotoxicity of monocrotaline in isolated rat hepatocytes: effects of dithiothreitol and fructose. Toxicon 2011; 57:1057-64. [PMID: 21530570 DOI: 10.1016/j.toxicon.2011.04.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 04/07/2011] [Accepted: 04/12/2011] [Indexed: 12/18/2022]
Abstract
Monocrotaline (MCT) is a pyrrolizidine alkaloid present in plants of the Crotalaria species that causes cytotoxicity and genotoxicity, including hepatotoxicity in animals and humans. It is metabolized by cytochrome P-450 in the liver to the alkylating agent dehydromonocrotaline (DHM). In previous studies using isolated rat liver mitochondria, we observed that DHM, but not MCT, inhibited the activity of respiratory chain complex I and stimulated the mitochondrial permeability transition with the consequent release of cytochrome c. In this study, we evaluated the effects of MCT and DHM on isolated rat hepatocytes. DHM, but not MCT, caused inhibition of the NADH-linked mitochondrial respiration. When hepatocytes of rats pre-treated with dexamethasone were incubated with MCT (5 mM), they showed ALT leakage, impaired ATP production and decreased levels of intracellular reduced glutathione and protein thiols. In addition, MCT caused cellular death by apoptosis. The addition of fructose or dithiotreitol to the isolated rat hepatocyte suspension containing MCT prevented the ATP depletion and/or glutathione or thiol oxidation and decreased the ALT leakage and apoptosis. These results suggest that the toxic effect of MCT on hepatocytes may be caused by metabolite-induced mitochondrial energetic impairment, together with a decrease of cellular glutathione and protein thiols.
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Affiliation(s)
- Marcos A Maioli
- Laboratório de Bioquímica Metabólica e Toxicológica, UNESP-Univ Estadual Paulista, Campus de Dracena, 17900-000 Dracena, SP, Brazil
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Zhu B, Zhai Q, Yu B. Tanshinone IIA protects rat primary hepatocytes against carbon tetrachloride toxicity via inhibiting mitochondria permeability transition. PHARMACEUTICAL BIOLOGY 2010; 48:484-487. [PMID: 20645787 DOI: 10.3109/13880200903179699] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Tanshinone IIA (Tan IIA), one of the key components of Salvia milthorrhiza Bunge (Lamiaceae), is used to treat liver disease. The present study was carried out to investigate the possible mechanisms involved in the hepatoprotective effects of Tan IIA on carbon tetrachloride (CCl(4))-induced hepatocyte toxicity. In cultures treated with 1 or 2 microM CCl(4), Tan IIA (10-75 microM) significantly increased hepatocyte survival rates. However, only at a concentration of 75 microM could Tan IIA partially reverse the CCl(4) (3 microM)-induced decrease of survival rate (34 +/- 3% vs. 18 +/- 3%, n = 8, p < 0.01). In isolated mitochondria energized with succinate, Tan IIA could inhibit the large swelling effect induced by CCl(4) (1 and 2 microM). Base on these results, Tan IIA could protect rat primary cultured hepatocytes from CCl(4)-induced toxicity partially by the inhibitory effect on the opening of mitochondrial permeability transition (MPT).
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Affiliation(s)
- Bin Zhu
- Department of Pharmacy, Fudan University Cancer Hospital, Shanghai, China.
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Kominkova V, Malekova L, Tomaskova Z, Slezak P, Szewczyk A, Ondrias K. Modulation of intracellular chloride channels by ATP and Mg2+. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1300-12. [PMID: 20206596 DOI: 10.1016/j.bbabio.2010.02.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 02/03/2010] [Accepted: 02/26/2010] [Indexed: 12/15/2022]
Abstract
We report the effects of ATP and Mg2+ on the activity of intracellular chloride channels. Mitochondrial and lysosomal membrane vesicles isolated from rat hearts were incorporated into bilayer lipid membranes, and single chloride channel currents were measured. The observed chloride channels (n=112) possessed a wide variation in single channel parameters and sensitivities to ATP. ATP (0.5-2 mmol/l) modulated and/or inhibited the chloride channel activities (n=38/112) in a concentration-dependent manner. The inhibition effect was irreversible (n=5/93) or reversible (n=15/93). The non-hydrolysable ATP analogue AMP-PNP had a similar inhibition effect as ATP, indicating that phosphorylation did not play a role in the ATP inhibition effect. ATP modulated the gating properties of the channels (n=6/93), decreased the channels' open dwell times and increased the gating transition rates. ATP (0.5-2 mmol/l) without the presence of Mg2+ decreased the chloride channel current (n=12/14), whereas Mg2+ significantly reversed the effect (n=4/4). We suggest that ATP-intracellular chloride channel interactions and Mg2+ modulation of these interactions may regulate different physiological and pathological processes.
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Affiliation(s)
- Viera Kominkova
- Institute of Molecular Physiology and Genetics, Centre of Excellence for Cardiovascular Research, Slovak Academy of Sciences, 83334 Bratislava, Slovakia
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Garcia AF, Medeiros HCD, Maioli MA, Lima MC, Rocha BA, da Costa FB, Curti C, Groppo M, Mingatto FE. Comparative effects of lantadene A and its reduced metabolite on mitochondrial bioenergetics. Toxicon 2010; 55:1331-7. [PMID: 20152851 DOI: 10.1016/j.toxicon.2010.02.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Revised: 01/23/2010] [Accepted: 02/03/2010] [Indexed: 11/24/2022]
Abstract
Lantana (Lantana camara Linn.) is a noxious weed to which certain medicinal properties have been attributed, but its ingestion has been reported to be highly toxic to animals and humans, especially in the liver. The main hepatotoxin in lantana leaves is believed to be the pentacyclic triterpenoid lantadene A (LA), but the precise mechanism by which it induces hepatotoxicity has not yet been established. This work addressed the action of LA and its reduced derivative (RLA) on mitochondrial bioenergetics. At the concentration range tested (5-25 microM), RLA stimulated state-4 respiration, inhibited state-3 respiration, circumvented oligomycin-inhibited state-3 respiration, dissipated membrane potential and depleted ATP in a concentration-dependent manner. However, LA did not stimulate state-4 respiration, nor did it affect the other mitochondrial parameters to the extent of its reduced derivative. The lantadenes didn't inhibit the CCCP-uncoupled respiration but increased the ATPase activity of intact coupled mitochondria. The ATPase activity of intact uncoupled or disrupted mitochondria was not affected by the compounds. We propose, therefore, that RLA acts as a mitochondrial uncoupler of oxidative phosphorylation, a property that arises from the biotransformation (reduction) of LA, and LA acts in other mitochondrial membrane components rather than the ATP synthase affecting the mitochondrial bioenergetics. Such effects may account for the well-documented hepatoxicity of lantana.
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Affiliation(s)
- Andréa F Garcia
- Laboratório de Bioquímica, Faculdade de Zootecnia, UNESP-Univ Estadual Paulista, Campus Experimental de Dracena, Dracena, SP 17900-000, Brazil
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19
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Requirement of a dopaminergic neuronal phenotype for toxicity of low concentrations of 1-methyl-4-phenylpyridinium to human cells. Toxicol Appl Pharmacol 2009; 241:23-35. [PMID: 19647008 DOI: 10.1016/j.taap.2009.07.027] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 07/17/2009] [Accepted: 07/23/2009] [Indexed: 12/21/2022]
Abstract
LUHMES cells are conditionally-immortalized non-transformed human fetal cells that can be differentiated to acquire a dopaminergic neuron-like phenotype under appropriate growth conditions. After differentiation by GDNF and cyclic adenosine monophosphate, LUHMES were sensitive to 1-methyl-4-phenylpyridinium (MPP(+)) toxicity at < or =5 microM, but resistant to the parental compound 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The high homogeneity and purity of the cultures allowed the detection of metabolic changes during the degeneration. Cellular ATP dropped in two phases after 24 and 48 h; cellular glutathione (GSH) decreased continuously, paralleled by an increase in lipid peroxidation. These events were accompanied by a time-dependent degeneration of neurites. Block of the dopamine transporter by GBR 12909 or mazindol completely abrogated MPP(+) toxicity. Inhibition of de novo dopamine synthesis by alpha-methyl-l-tyrosine or 3-iodo-l-tyrosine attenuated toxicity, but did not reduce the initial drop in ATP. Inhibition of mixed lineage kinases by CEP1347 completely prevented the MPP(+)-induced loss of viability and intracellular GSH, but failed to attenuate the initial drop of ATP. For the quantitative assessment of neurite degeneration, an automated imaging-based high content screening approach was applied and confirmed the findings made by pharmacological interventions in this study. Our data indicate that inhibition of mitochondrial ATP synthesis is not sufficient to trigger cell death in MPP(+)-treated LUHMES.
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Carlson C, Hussain SM, Schrand AM, K. Braydich-Stolle L, Hess KL, Jones RL, Schlager JJ. Unique Cellular Interaction of Silver Nanoparticles: Size-Dependent Generation of Reactive Oxygen Species. J Phys Chem B 2008; 112:13608-19. [DOI: 10.1021/jp712087m] [Citation(s) in RCA: 1316] [Impact Index Per Article: 82.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- C. Carlson
- Applied Biotechnology Branch, Human Effectiveness Directorate, and Science Applications International Corporation, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433
| | - S. M. Hussain
- Applied Biotechnology Branch, Human Effectiveness Directorate, and Science Applications International Corporation, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433
| | - A. M. Schrand
- Applied Biotechnology Branch, Human Effectiveness Directorate, and Science Applications International Corporation, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433
| | - L. K. Braydich-Stolle
- Applied Biotechnology Branch, Human Effectiveness Directorate, and Science Applications International Corporation, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433
| | - K. L. Hess
- Applied Biotechnology Branch, Human Effectiveness Directorate, and Science Applications International Corporation, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433
| | - R. L. Jones
- Applied Biotechnology Branch, Human Effectiveness Directorate, and Science Applications International Corporation, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433
| | - J. J. Schlager
- Applied Biotechnology Branch, Human Effectiveness Directorate, and Science Applications International Corporation, Air Force Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio 45433
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Zhao Y, Xie P, Tang R, Zhang X, Li L, Li D. In vivo studies on the toxic effects of microcystins on mitochondrial electron transport chain and ion regulation in liver and heart of rabbit. Comp Biochem Physiol C Toxicol Pharmacol 2008; 148:204-10. [PMID: 18590982 DOI: 10.1016/j.cbpc.2008.05.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2008] [Revised: 05/19/2008] [Accepted: 05/20/2008] [Indexed: 11/24/2022]
Abstract
This study examined the toxic effects of microcystins on mitochondria of liver and heart of rabbit in vivo. Rabbits were injected i.p. with extracted microcystins (mainly MC-RR and -LR) at two doses, 12.5 and 50 MC-LReq. microg/kg bw, and the changes in mitochondria of liver and heart were studied at 1, 3, 12, 24 and 48 h after injection. MCs induced damage of mitochondrial morphology and lipid peroxidation in both liver and heart. MCs influenced respiratory activity through inhibiting NADH dehydrogenase and enhancing succinate dehydrogenase (SDH). MCs altered Na(+)-K(+)-ATPase and Ca(2+)-Mg(2+)-ATPase activities of mitochondria and consequently disrupted ionic homeostasis, which might be partly responsible for the loss of mitochondrial membrane potential (MMP). MCs were highly toxic to mitochondria with more serious damage in liver than in heart. Damage of mitochondria showed reduction at 48 h in the low dose group, suggesting that the low dose of MCs might have stimulated a compensatory response in the rabbits.
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Affiliation(s)
- Yanyan Zhao
- Fisheries College of Huazhong Agricultural University; Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, Wuhan 430070, People's Republic of China
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22
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Zhang Y, Qi X, Gong L, Li Y, Liu L, Xue X, Xiao Y, Wu X, Ren J. Roles of reactive oxygen species and MAP kinases in the primary rat hepatocytes death induced by toosendanin. Toxicology 2008; 249:62-8. [PMID: 18499325 DOI: 10.1016/j.tox.2008.04.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Revised: 04/08/2008] [Accepted: 04/08/2008] [Indexed: 01/11/2023]
Abstract
Toosendanin (Tsn), a triterpenoid extracted from Melia toosendan Sieb et Zucc, possesses different pharmacological effects in human and important values in agriculture. However, liver injury has been reported when toosendanin or Melia-family plants, which contain toosendanin are applied. The mechanism by which toosendanin induces liver injury remains largely unknown. Here we reported that toosendanin induced primary rat hepatocytes death by mitochondrial dysfunction and caspase activation. Toosendanin led to decrease of mitochondrial membrane potential, fall in intracellular ATP level, release of cytochrome c to cytoplasm, activation of caspase-8, 9, and 3 and ultimately cell death. Level of reactive oxygen species (ROS) was also increased in hepatocytes after incubation with toosendanin. Catalase, the H2O2-decomposing enzyme, can prevent the reduction in ATP level and protect hepatocytes from toosendanin-induced death. The ERK1/2 (p44/42 MAP kinases) and JNK (c-Jun N-terminal kinase) were activated, but p38 MAPK was not activated by toosendanin. Inhibition of ERK1/2 activation sensitized hepatocytes to death and increased activity of caspase-9 and 3 in response to toosendanin. Inhibition of JNK attenuated toosendanin-induced cell death. These results suggested that toosendanin causes death of primary rat hepatocytes by mitochondrial dysfunction and caspase activation. Generation of ROS and MAP kinases activation might be involved in this process.
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Affiliation(s)
- Yunhai Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 201203, China
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23
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Qi X, Cai Y, Gong L, Liu L, Chen F, Xiao Y, Wu X, Li Y, Xue X, Ren J. Role of mitochondrial permeability transition in human renal tubular epithelial cell death induced by aristolochic acid. Toxicol Appl Pharmacol 2007; 222:105-10. [PMID: 17521691 DOI: 10.1016/j.taap.2007.03.029] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2006] [Revised: 03/26/2007] [Accepted: 03/30/2007] [Indexed: 10/23/2022]
Abstract
Aristolochic acid (AA), a natural nephrotoxin and carcinogen, can induce a progressive tubulointerstitial nephropathy. However, the mechanism by which AA causes renal injury remains largely unknown. Here we reported that the mitochondrial permeability transition (MPT) plays an important role in the renal injury induced by aristolochic acid I (AAI). We found that in the presence of Ca(2+), AAI caused mitochondrial swelling, leakage of Ca(2+), membrane depolarization, and release of cytochrome c in isolated kidney mitochondria. These alterations were suppressed by cyclosporin A (CsA), an agent known to inhibit MPT. Culture of HK-2 cell, a human renal tubular epithelial cell line for 24 h with AAI caused a decrease in cellular ATP, mitochondrial membrane depolarization, cytochrome c release, and increase of caspase 3 activity. These toxic effects of AAI were attenuated by CsA and bongkrekic acid (BA), another specific MPT inhibitor. Furthermore, AAI greatly inhibited the activity of mitochondrial adenine nucleotide translocator (ANT) in isolated mitochondria. We suggested that ANT may mediate, at least in part, the AAI-induced MPT. Taken together, these results suggested that MPT plays a critical role in the pathogenesis of HK-2 cell injury induced by AAI and implied that MPT might contribute to human nephrotoxicity of aristolochic acid.
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Affiliation(s)
- Xinming Qi
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 201203, China
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Senthil V, Ramadevi S, Venkatakrishnan V, Giridharan P, Lakshmi BS, Vishwakarma RA, Balakrishnan A. Withanolide induces apoptosis in HL-60 leukemia cells via mitochondria mediated cytochrome c release and caspase activation. Chem Biol Interact 2007; 167:19-30. [PMID: 17328876 DOI: 10.1016/j.cbi.2007.01.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2006] [Revised: 12/25/2006] [Accepted: 01/02/2007] [Indexed: 10/23/2022]
Abstract
The present study is on the growth inhibitory effect of Withania somnifera methanolic leaf extract and its active component, withanolide on HL-60 promyelocytic leukemia cells. The decrease in survival rate of HL-60 cells was noted to be associated with a time dependent decrease in the Bcl-2/Bax ratio, leading to up regulation of Bax. Both the crude leaf extract and the active component activated the apoptotic cascade through the cytochrome c release from mitochondria. The activation of caspase 9, caspase 8 and caspase 3 revealed that caspase was a key mediator in the apoptotic pathway. DNA fragmentation analysis revealed typical ladders as early as 12h indicative of caspase 3 role in the apoptotic pathway. Flow cytometry data demonstrated an increase of sub-G1 peak upon treatment by 51% at 24h, suggesting the induction of apoptotic cell death in HL-60 cells.
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Affiliation(s)
- V Senthil
- Centre For Biotechnology, Anna University, Chennai 600025, Tamil Nadu, India
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M'Bemba-Meka P, Lemieux N, Chakrabarti SK. Role of oxidative stress, mitochondrial membrane potential, and calcium homeostasis in nickel subsulfide-induced human lymphocyte death in vitro. THE SCIENCE OF THE TOTAL ENVIRONMENT 2006; 369:21-34. [PMID: 16780931 DOI: 10.1016/j.scitotenv.2006.04.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2005] [Revised: 03/26/2006] [Accepted: 04/03/2006] [Indexed: 05/10/2023]
Abstract
When isolated human lymphocytes were treated in vitro either with various concentrations (0-2 mM) of soluble form of nickel subsulfide (Ni3S2) at 37 degrees C for 4 h or at various times (0-240 min), both concentration- and time-dependent effects of Ni3S2 on lymphocyte death were observed. Increased generation of hydrogen peroxide (H2O2), and superoxide anion (O2-), lipid peroxidation and depletion of both nonprotein (NP-) and protein (P-) sulfhydryl (SH) contents were induced by 1 mM Ni3S2. Ni3S2-induced lymphocyte death was significantly prevented by pre-treatment with either catalase (a H2O2 scavenger), or superoxide dismutase (scavenger of O2- radical), or dimethylthiourea/mannitol (hydroxyl radical scavengers), or deferoxamine (iron-chelator), or glutathione/N-acetylcysteine. Co-treatment with cyclosporin A (a mitochondrial membrane potential' inhibitor) inhibited Ni3S2-induced disturbances in mitochondrial membrane potential, and significantly prevented Ni3S2-induced lymphocyte death. Ni3S2-induced lymphocyte death was also significantly prevented by modulating intracellular calcium fluxes using both Ca2+ channel blockers and intracellular Ca2+ antagonists. Thus, the mechanism of soluble Ni3S2-induced activation of lymphocyte death signalling pathways involves increasing generation of different types of oxidative stress, disturbances in mitochondrial membrane potential and cellular calcium homeostasis' destabilization.
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Affiliation(s)
- Prosper M'Bemba-Meka
- Human Toxicology Research Group (TOXHUM), Department of Environmental and Occupational Health, Faculty of Medicine, Université de Montréal PO Box 6128, Main Station, Montréal, Québec, Canada H3C 3J7.
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26
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Leite S, Martins NM, Dorta DJ, Curti C, Uyemura SA, dos Santos AC. Mitochondrial Uncoupling by the Sulindac Metabolite, Sulindac Sulfide. Basic Clin Pharmacol Toxicol 2006; 99:294-9. [PMID: 17040214 DOI: 10.1111/j.1742-7843.2006.pto_490.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Sulindac is a non-steroidal antiinflammatory drug (NSAID) known to inhibit cyclooxygenases (COX) 1 and 2, and at present of interest for cancer prevention. However, its therapeutic use has been limited by its toxicity to the gastrointestinal tract and liver. We address the effects of sulindac, of the pharmacologically inactive metabolite, sulindac sulfone, and of the pharmacologically active metabolite, sudindac sulfide, on isolated rat liver mitochondria and HepG2 cells. Sulindac sulfide, but not sulindac sulfone or sulindac itself, caused mitochondrial uncoupling, released preaccumulated Ca2+ from the organelle, and decreased Hep-G2 cell viability in apparent association with cell ATP depletion resulting from mitochondrial uncoupling-associated membrane potential dissipation.
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Affiliation(s)
- Samara Leite
- Department of Clinical Analysis, Toxicology, Bromatology, Faculty of Pharmaceutical Sciences, Ribeirao Preto-USP, Sao Paulo, Brazil
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M'Bemba-Meka P, Lemieux N, Chakrabarti SK. Role of oxidative stress, mitochondrial membrane potential, and calcium homeostasis in human lymphocyte death induced by nickel carbonate hydroxide in vitro. Arch Toxicol 2006; 80:405-20. [PMID: 16758152 DOI: 10.1007/s00204-006-0060-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Accepted: 11/29/2005] [Indexed: 10/24/2022]
Abstract
When isolated human lymphocytes were treated in vitro with various concentrations of soluble form of nickel carbonate hydroxide (NiCH) (0-1 mM), at 37 degrees C for 4 h, both concentration- and time-dependent effects of NiCH on lymphocyte death were observed. Increased generation of hydrogen peroxide (H(2)O(2)), superoxide anion (O(2)(-) ), depletion of both no protein (NP-) and protein (P-) sulfhydryl (SH) contents and lipid peroxidation (LPO) were induced by NiCH. Pretreatment of lymphocytes with either catalase (H(2)O(2) scavenger), or deferoxamine (DFO) (iron chelator), or excess glutathione (GSH) (an antioxidant) not only significantly reduced the NiCH-induced generation of H(2)O(2) and LPO, but also increased the NP-SH and P-SH contents initially reduced by NiCH. NiCH-induced generation of excess O(2)(-) but not excess LPO was significantly reduced by pretreatment with superoxide dismutase (SOD). NiCH-induced lymphocyte death was significantly prevented by pre-treatment with either catalase, or dimethylthiourea/mannitol (hydroxyl radical scavengers), or DFO, or excess GSH/N-acetylcysteine. NiCH-induced lymphocyte death was also significantly prevented by pretreatment with excess SOD. Thus, various types of oxidative stresses play an important role in NiCH-induced lymphocyte death. Cotreatment with cyclosporin A (a specific inhibitor of alteration in mitochondrial membrane potential (DeltaPsi(m)) not only inhibited NiCH-induced alteration in DeltaPsi(m), but also significantly prevented Ni-compound-induced lymphocyte death. Furthermore, NiCH-induced destabilization of cellular calcium homeostasis. As such, NiCH-induced lymphocyte death was significantly prevented by modulating intracellular calcium fluxes such as Ca(2+) channel blockers and intracellular Ca(2+) antagonist. Thus, the mechanism of NiCH (soluble form)-induced activation of lymphocyte death signalling pathways involves not only the excess generation of different types of oxidative stress, but also the induction of alteration in DeltaPsi(m) and destabilization of cellular calcium homeostasis as well.
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Affiliation(s)
- Prosper M'Bemba-Meka
- Human Toxicology Research Group, TOXHUM, Department of Environmental and Occupational Health, Faculty of Medicine, Université de Montréal, Main Station , P.O. Box 6128, H3C 3J7, Montréal, QC, Canada.
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M'Bemba-Meka P, Lemieux N, Chakrabarti SK. Role of oxidative stress, mitochondrial membrane potential, and calcium homeostasis in nickel sulfate-induced human lymphocyte death in vitro. Chem Biol Interact 2005; 156:69-80. [PMID: 16125158 DOI: 10.1016/j.cbi.2005.07.004] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2005] [Revised: 07/13/2005] [Accepted: 07/22/2005] [Indexed: 11/18/2022]
Abstract
When isolated human lymphocytes were treated in vitro with various concentrations of nickel sulfate (NiSO4) (0-4 mM) at 37 degrees C for 4 h, both concentration- and time-dependent effects of NiSO4 on lymphocyte death were observed. Increased generation of hydrogen peroxide, depletion of both nonprotein and protein sulfhydryl contents, and lipid peroxidation were induced by NiSO4. NiSO4-induced lymphocyte death was significantly prevented by pre-treatment with either catalase, or dimethylthiourea/mannitol, or deferoxamine, or excess glutathione/N-acetylcysteine. Cotreatment with cyclosporin A (a specific inhibitor of mitochondrial membrane potential) not only inhibited NiSO4-induced mitochondrial membrane potential, but also significantly prevented Ni compound-induced lymphocyte death. NiSO4-induced lymphocyte death was also significantly prevented by modulating intracellular calcium fluxes using both Ca2+ channel blockers and intracellular Ca2+ antagonist. Thus, the mechanism of NiSO4-induced activation of lymphocyte death signalling pathways involves not only the excess generation of different types of oxidative stress but also NiSO4-induced loss of mitochondrial membrane potential and destabilization of cellular calcium homeostasis as well.
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Affiliation(s)
- Prosper M'Bemba-Meka
- Human Toxicology Research Group (TOXHUM), Department of Environmental and Occupational Health, Faculty of Medicine, Université de Montréal, P.O. Box 6128, Main Station, Montréal, Que., Canada H3C 3J7
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29
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Chen T, Pearce LL, Peterson J, Stoyanovsky D, Billiar TR. Glutathione depletion renders rat hepatocytes sensitive to nitric oxide donor-mediated toxicity. Hepatology 2005; 42:598-607. [PMID: 16116630 DOI: 10.1002/hep.20813] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Nitric oxide (NO) can be either cytoprotective or cytotoxic in hepatocytes, depending on conditions within the cell. We hypothesized that redox status is a determinant of NO effects on cell viability. To cause the disturbance of redox homeostasis in the hepatocytes, cells were treated with the following glutathione (GSH) depleting agents: (1) chronic depletion by 18 hours pretreatment with buthionine sulfoximine (BSO), which depletes GSH by blocking its biosynthesis; and (2) acute depletion by 1 hour pretreatment with diethyl maleate (DEM), which conjugates GSH by the GSH-S-transferase catalyzed reaction. S-nitroso-N-acetyl-D,L-penicillamine (SNAP), a NO donor, was added after removal of GSH-depleting agents. Individual treatment with either SNAP or GSH depletion did not appreciably affect viability. A significant increase of cytotoxicity in hepatocytes was observed with the combination of a concentration and time course regimen of SNAP and GSH depletion. SNAP treatment of GSH-depleted hepatocytes led to an increase in LDH release and oxidative stress, disruption of mitochondrial membrane potential, the presence of nitrotyrosine (an indicator of peroxynitrite (ONOO-) generation), and a decrease in adenosine triphosphate (ATP) content. The interference of mitochondrial respiratory enzymes, especially with the combination treatments, indicated different levels of disturbance of electron transfer, superoxide generation, and ATP production. Other commonly used NO donors were found to exhibit lower and slower toxicity in the setting of GSH depletion than that evident with SNAP. In conclusion, the disruption of cellular redox homeostasis by GSH depletion leads hepatocytes to be more susceptible to NO (especially S-nitrosothiols) and subsequent necrotic cell death.
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Affiliation(s)
- Tracy Chen
- Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
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Hussain SM, Hess KL, Gearhart JM, Geiss KT, Schlager JJ. In vitro toxicity of nanoparticles in BRL 3A rat liver cells. Toxicol In Vitro 2005; 19:975-83. [PMID: 16125895 DOI: 10.1016/j.tiv.2005.06.034] [Citation(s) in RCA: 1196] [Impact Index Per Article: 62.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Accepted: 06/17/2005] [Indexed: 11/19/2022]
Abstract
This study was undertaken to address the current deficient knowledge of cellular response to nanosized particle exposure. The study evaluated the acute toxic effects of metal/metal oxide nanoparticles proposed for future use in industrial production methods using the in vitro rat liver derived cell line (BRL 3A). Different sizes of nanoparticles such as silver (Ag; 15, 100 nm), molybdenum (MoO(3); 30, 150 nm), aluminum (Al; 30, 103 nm), iron oxide (Fe(3)O(4); 30, 47 nm), and titanium dioxide (TiO(2); 40 nm) were evaluated for their potential toxicity. We also assessed the toxicity of relatively larger particles of cadmium oxide (CdO; 1 microm), manganese oxide (MnO(2); 1-2 microm), and tungsten (W; 27 microm), to compare the cellular toxic responses with respect to the different sizes of nanoparticles with different core chemical compositions. For toxicity evaluations, cellular morphology, mitochondrial function (MTT assay), membrane leakage of lactate dehydrogenase (LDH assay), reduced glutathione (GSH) levels, reactive oxygen species (ROS), and mitochondrial membrane potential (MMP) were assessed under control and exposed conditions (24h of exposure). Results showed that mitochondrial function decreased significantly in cells exposed to Ag nanoparticles at 5-50 microg/ml. However, Fe(3)O(4), Al, MoO(3) and TiO(2) had no measurable effect at lower doses (10-50 microg/ml), while there was a significant effect at higher levels (100-250 microg/ml). LDH leakage significantly increased in cells exposed to Ag nanoparticles (10-50 microg/ml), while the other nanoparticles tested displayed LDH leakage only at higher doses (100-250 microg/ml). In summary the Ag was highly toxic whereas, MoO(3) moderately toxic and Fe(3)O(4), Al, MnO(2) and W displayed less or no toxicity at the doses tested. The microscopic studies demonstrated that nanoparticle-exposed cells at higher doses became abnormal in size, displaying cellular shrinkage, and an acquisition of an irregular shape. Due to toxicity of silver, further study conducted with reference to its oxidative stress. The results exhibited significant depletion of GSH level, reduced mitochondrial membrane potential and increase in ROS levels, which suggested that cytotoxicity of Ag (15, 100 nm) in liver cells is likely to be mediated through oxidative stress.
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Affiliation(s)
- S M Hussain
- Applied Biotechnology, Air Force Research Laboratory/HEPB, Wright-Patterson AFB, OH, USA.
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Gellerich FN, Trumbeckaite S, Müller T, Deschauer M, Chen Y, Gizatullina Z, Zierz S. Energetic depression caused by mitochondrial dysfunction. Mol Cell Biochem 2004; 256-257:391-405. [PMID: 14977198 DOI: 10.1023/b:mcbi.0000009885.34498.e6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Mitochondria, providing most of ATP needed for cell work, realizing numerous specific functions as biosyntheses or degradations, contributing to Ca2+ signalling also play a key role in the pathways to cell death. Impairment of mitochondrial functions caused by mutations of mt-genome and by acute processes are responsible for numerous diseases. The relations between changes on the level of molecules and the clinical state are rather complex, and the prediction of thresholds is difficult. Therefore investigations on different levels of an organismus (genome, metabolites, enzymes, mitochondrial function in vivo and in vitro) are necessary (multi level approach). Metabolic control theory is a valuable tool for understanding the different effects of mutations on the level of enzyme activities and mitochondrial function. Decreased concentrations of adenine nucleotides, leaky outer and inner mitochondrial membranes, decreased rates of mitochondrial linked pathways and decreased activities of respiratory chain enzymes contribute to depression of cellular energy metabolism characterized by decreased cytosolic phosphorylation potentials as one of the most important consequences of mitochondrial impairments. This review regards classical bioenergetic mechanisms of mitochondrial impairment which contribute to energetic depression.
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Affiliation(s)
- Frank Norbert Gellerich
- Muskellabor der Neurologischen Klinik, Martin-Luther-Universität Halle-Wittenberg, Halle/Saale, Germany.
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Drew B, Leeuwenburgh C. Method for measuring ATP production in isolated mitochondria: ATP production in brain and liver mitochondria of Fischer-344 rats with age and caloric restriction. Am J Physiol Regul Integr Comp Physiol 2003; 285:R1259-67. [PMID: 12855419 DOI: 10.1152/ajpregu.00264.2003] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The production of ATP is vital for muscle contraction, chemiosmotic homeostasis, and normal cellular function. Many studies have measured ATP content or qualitative changes in ATP production, but few have quantified ATP production in vivo in isolated mitochondria. Because of the importance of understanding the energy capacity of mitochondria in biology, physiology, cellular dysfunction, and ultimately, disease pathologies and normal aging, we modified a commercially available bioluminescent ATP determination assay for quantitatively measuring ATP content and rate of ATP production in isolated mitochondria. The bioluminescence assay is based on the reaction of ATP with recombinant firefly luciferase and its substrate luciferin. The stabilities of the reaction mixture as well as relevant ATP standards were quantified. The luminescent signals of the reaction mixture and a 0.5 microM ATP standard decreased linearly at rates of 2.16 and 1.39% decay/min, respectively. For a 25 microM ATP standard, the luminescent signal underwent a logarithmic decay, due to intrinsic deviations from the Beer-Lambert law. Moreover, to test the functionality of isolated mitochondria, they were incubated with 1 and 5 mM oligomycin, an inhibitor of oxidative phosphorylation. The rate of ATP production in the mitochondria declined by 34 and 83%, respectively. Due to the sensitivity and stability of the assay and methodology, we were able to quantitatively measure in vivo the effects of age and caloric restriction on the ATP content and production in isolated mitochondria from the brain and liver of young and old Fischer-344 rats. In both tissues, neither age nor caloric restriction had any significant effect on the ATP content or the rate of ATP production. This study introduces a highly sensitive, reproducible, and quick methodology for measuring ATP in isolated mitochondria.
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Affiliation(s)
- Barry Drew
- Univ. of Florida, Biochemistry of Aging Laboratory, P.O. Box 118206, Gainesville, FL 32611, USA
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Thompson RW, Valentine HL, Valentine WM. Cytotoxic mechanisms of hydrosulfide anion and cyanide anion in primary rat hepatocyte cultures. Toxicology 2003; 188:149-59. [PMID: 12767687 DOI: 10.1016/s0300-483x(03)00079-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Hydrogen sulfide and hydrogen cyanide are known to compromise mitochondrial respiration through inhibition of cytochrome c oxidase and this is generally considered to be their primary mechanism of toxicity. Experimental studies and the efficiency of current treatment protocols suggest that H(2)S may exert adverse physiological effects through additional mechanisms. To evaluate the role of alternative mechanisms in H(2)S toxicity, the relative contributions of electron transport inhibition, uncoupling of mitochondrial respiration, and opening of the mitochondrial permeability transition pore (MPTP) to hydrosulfide and cyanide anion cytotoxicity in primary hepatocyte cultures were examined. Supplementation of hepatocytes with the glycolytic substrate, fructose, rescued hepatocytes from cyanide anion induced toxicity, whereas fructose supplementation increased hydrosulfide anion toxicity suggesting that hydrosulfide anion may compromise glycolysis in hepatocytes. Although inhibitors of the MPTP opening were protective for hydrosulfide anion, they had no effect on cyanide anion toxicity, consistent with an involvement of the permeability transition pore in hydrosulfide anion toxicity but not cyanide anion toxicity. Exposure of isolated rat liver mitochondria to hydrosulfide did not result in large amplitude swelling suggesting that if H(2)S induces the permeability transition it does so indirectly through a mechanism requiring other cellular components. Hydrosulfide anion did not appear to be an uncoupler of mitochondrial respiration in hepatocytes based upon the inability of oligomycin and fructose to protect hepatocytes from hydrosulfide anion toxicity. These findings support mechanisms additional to inhibition of cytochrome c oxidase in hydrogen sulfide toxicity. Further investigations are required to assess the role of the permeability transition in H(2)S toxicity, determine whether similar affects occur in other cell types or in vivo and evaluate whether this may provide a basis for the design of more effective therapeutic measures for hydrogen sulfide intoxication.
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Affiliation(s)
- Rodney W Thompson
- Department of Pathology and Center in Molecular Toxicology, Vanderbilt University Medical Center, Rm 109 MCS Annex Bldg., 1401 21st Ave South, Nashville, TN 37232-2561, USA
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Hussain SM, Frazier JM. Involvement of apoptosis in hydrazine induced toxicity in rat primary hepatocytes. Toxicol In Vitro 2003; 17:343-55. [PMID: 12781213 DOI: 10.1016/s0887-2333(03)00022-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The current study was undertaken to investigate the role of apoptosis in hydrazine induced hepatotoxicity. Hepatocytes were exposed to hydrazinium nitrate (HzN) at two doses (50 and 75 mM) for 2 h then placed in fresh HzN-free media and cultured for an additional 24 h. Post-exposure, cell viability was evaluated at several time points by lactate dehydrogenase (LDH) leakage and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction. Markers of apoptosis (mitochondrial membrane potential, annexin binding, DNA fragmentation, caspase activation, and cytochrome c release) were measured 24 h post-exposure. The viability data showed time dependent increase in LDH leakage at 75 mM of HzN, with only a slight increase at 50 mM. MTT reduction showed a decrease in mitochondrial activity at both doses immediately after the 2 h continuous exposure. However, MTT reduction returned to normal at 50 mM while at 75 mM, MTT reduction initially recovered but then deteriorated to approximately 50% of controls at 24 h post-exposure. Based on viability data, exposure to 50 mM HzN for 2 h is a marginally toxic dose while 75 mM is a significantly toxic dose. The results for apoptosis biomarkers showed a reduction in mitochondrial membrane potential, an increase in annexin binding, an increase in total caspase activity, moderate activation of caspase-3, and release of cytochrome c. However, the appearance of DNA fragmentation in HzN exposed cells was very low compared to positive controls (cadmium and cyclosporine). The possibility that HzN induces apoptosis without the involvement of DNA fragmentation can not be ruled out. The present results, overall, suggest that apoptosis may be a contributing factor in acute HzN toxicity.
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Affiliation(s)
- Saber M Hussain
- ManTech Environmental Technology, Inc. 45437, Dayton, OH, USA.
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Nakai M, Mori A, Watanabe A, Mitsumoto Y. 1-methyl-4-phenylpyridinium (MPP+) decreases mitochondrial oxidation-reduction (REDOX) activity and membrane potential (Deltapsi(m)) in rat striatum. Exp Neurol 2003; 179:103-10. [PMID: 12504872 DOI: 10.1006/exnr.2002.8056] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mitochondrial dysfunction has long been implicated in the death of nigrostriatal dopaminergic neurons in Parkinson's disease (PD) and its experimental models. Here we further analyzed changes in the mitochondrial oxidation-reduction (REDOX) activity and membrane potential (Deltapsi(m)) of striatal synaptosomes after the infusion of 1-methyl-4-phenylpyridinium (MPP+) into rat striatum. MPP+ (40 nmol) treatment produced decreases in mitochondrial REDOX activity and Deltapsi(m) at 18 h, as measured by fluorometric analysis with both Alamar blue and JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyanine iodide) dyes. At this time point, tyrosine hydroxylase (TH) and dopamine transporter (DAT) protein levels were not altered, but both decreased at 7 days after MPP+ (40 nmol) infusion. Both measures of mitochondrial dysfunction induced by MPP+ (40 nmol) at 18 h were attenuated, at least in part, by pretreatment with a selective dopamine uptake inhibitor GBR-12909 (1-(2-(bis(4-fluorophenyl)methoxy)ethyl)-4-(3-phenylpropyl) piperazine). In addition, GBR-12909 partially attenuated MPP+ (40 nmol)-caused a loss of striatal nerve terminal as indicated by decreases in TH and DAT immunoreactivities as well as dopamine and its metabolites levels. The present study indicates that decreases in mitochondrial REDOX activity and Deltapsi(m) may play a role in MPP+ -induced dopaminergic neurotoxicity, and further provides that improvement of mitochondrial dysfunction may be a better way to slow progressive dopaminergic neurodegeneration commonly associated with PD.
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Affiliation(s)
- Masami Nakai
- Research Unit for Neurological Diseases, Second Institute of New Drug Discovery, Otsuka Pharmaceutical Co., Ltd. Tokushima 771-0192, Japan
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Ortiz GG, Zúñiga-González G, García JJ, Torres-Bugarín O, Zamora-Perez A, Bitzer-Quintero OK. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced lipid peroxidation and DNA damage in mouse bone marrow and blood. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2003; 41:64-68. [PMID: 12552593 DOI: 10.1002/em.10133] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a neurotoxin that induces Parkinsonism in humans, monkeys, and mice and oxidative stress in mammalian cells and tissues. In the present study, the relationship between the generation of lipid peroxidation products and DNA damage was studied in mice treated with MPTP. The frequency of micronucleated polychromatic erythrocytes (MN-PCE) and the concentrations of malonaldehyde and 4-hydroxyalkenals were determined in the bone marrow and peripheral blood of mice 0, 24, 48, 72, and 96 hr after treatment with MPTP, cyclophosphamide as a positive control, or diluent. Both MN-PCE and the lipid peroxidation products increased in MPTP-treated mice, with significant levels being detected in bone marrow starting at 24 hr after treatment and in blood starting at 48 hr after treatment. These results suggest that the generation of oxidative products is related to the DNA damage produced by MPTP in mice.
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Affiliation(s)
- Genaro G Ortiz
- División de Neurociencias, Centro de Investigación Biomédica de Occidente (CIBO), Instituto Mexicano del Seguro Social (IMSS), Sierra Mojada 800, CP 44340, Guadalajara, Jalisco, Mexico.
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Mingatto FE, Rodrigues T, Pigoso AA, Uyemura SA, Curti C, Santos AC. The critical role of mitochondrial energetic impairment in the toxicity of nimesulide to hepatocytes. J Pharmacol Exp Ther 2002; 303:601-7. [PMID: 12388641 DOI: 10.1124/jpet.102.038620] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We described the effects of nimesulide (N-[4-nitro-2-phenoxyphenyl]-methanesulfonamide) and its reduced metabolite in isolated rat hepatocytes. Nimesulide stimulated the succinate-supported state 4 respiration of mitochondria, indicating an uncoupling effect of the drug. Incubation of hepatocytes with nimesulide (0.1-1 mM) elicited a concentration- and time-dependent decrease in cell viability as assessed by lactate dehydrogenase leakage, a decrease of mitochondrial membrane potential as assessed by rhodamine 123 retention, and cell ATP depression. Nimesulide also decreased the levels of NAD(P)H and glutathione in hepatocytes, but the extent of the effects was less pronounced in relation to the energetic parameters; in addition, these effects did not imply the peroxidation of membrane lipids. The decrease in the viability of hepatocytes was prevented by fructose and, to a larger extent, by fructose plus oligomycin; it was stimulated by proadifen, a cytochrome P450 inhibitor. In contrast, the reduced metabolite of nimesulide did not present any of the effects observed for the parent drug. These results indicate that: 1) nimesulide causes injury to the isolated rat liver cells, 2) this effect is mainly mediated by impairment of ATP production by mitochondria due to uncoupling, and 3) on account of the activity of its nitro group, the parent drug by itself is the main factor responsible for its toxicity to the hepatocytes.
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Affiliation(s)
- Fábio E Mingatto
- Departamento de Física e Química, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas, Universidade de São Paulo, Av. Café s/n, 14040-903 Ribeirão Preto, São Paulo, Brazil
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Lemasters JJ, Qian T, He L, Kim JS, Elmore SP, Cascio WE, Brenner DA. Role of mitochondrial inner membrane permeabilization in necrotic cell death, apoptosis, and autophagy. Antioxid Redox Signal 2002; 4:769-81. [PMID: 12470504 DOI: 10.1089/152308602760598918] [Citation(s) in RCA: 271] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Inhibition of mitochondrial oxidative phosphorylation progresses to uncoupling when opening of cyclosporin A-sensitive permeability transition pores increases permeability of the mitochondrial inner membrane to small solutes. Involvement of the mitochondrial permeability transition (MPT) in necrotic and apoptotic cell death is implicated by demonstrations of protection by cyclosporin A against oxidative stress, ischemia/reperfusion, tumor necrosis factor-alpha exposure, Fas ligation, calcium overload, and a variety of toxic chemicals. Confocal microscopy directly visualizes the MPT in single mitochondria within living cells from the translocation of impermeant fluorophores, such as calcein, across the inner membrane. Simultaneously, mitochondria release potential-indicating fluorophores. Subsequently, mitochondria swell, causing outer membrane rupture and release of cytochrome c and other proapoptotic proteins from the intermembrane space. In situ a sequence of decreased NAD(P)H, increased free calcium, and increased reactive oxygen species formation within mitochondria promotes the MPT and subsequent cell death. Necrotic and apoptotic cell death after the MPT depends, in part, on ATP levels. If ATP levels fall profoundly, glycine-sensitive plasma membrane permeabilization and rupture ensue. If ATP levels are partially maintained, apoptosis follows the MPT. The MPT also signals mitochondrial autophagy, a process that may be important in removing damaged mitochondria. Cellular features of necrosis, apoptosis, and autophagy frequently occur together after death signals and toxic stresses. A new term, necrapoptosis, describes such death processes that begin with a common stress or death signal, progress by shared pathways, but culminate in either cell lysis (necrosis) or programmed cellular resorption (apoptosis), depending on modifying factors such as ATP.
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Affiliation(s)
- John J Lemasters
- Department of Cell and Developmental Biology, University of North Carolina, Chapel Hill, North Carolina 27599-7090, USA.
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Dryhurst G. Are dopamine, norepinephrine, and serotonin precursors of biologically reactive intermediates involved in the pathogenesis of neurodegenerative brain disorders? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2002; 500:373-96. [PMID: 11764972 DOI: 10.1007/978-1-4615-0667-6_61] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Affiliation(s)
- G Dryhurst
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman 73019, USA
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Masubuchi Y, Nakayama S, Horie T. Role of mitochondrial permeability transition in diclofenac-induced hepatocyte injury in rats. Hepatology 2002; 35:544-51. [PMID: 11870366 DOI: 10.1053/jhep.2002.31871] [Citation(s) in RCA: 125] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
Abstract
Hepatotoxicity of diclofenac has been known in experimental animals and humans but its mechanism has not been fully understood. The present study examined the role of mitochondrial permeability transition (MPT) in the pathogenesis of diclofenac-induced hepatocyte injury by using isolated mitochondria and primary culture hepatocytes from rats. Incubation of energized mitochondria with succinate in the presence of Ca(2+) and diclofenac resulted in mitochondrial swelling, leakage of accumulated Ca(2+), membrane depolarization, and oxidation of nicotinamide adenine dinucleotide phosphate and protein thiol. All of these phenomena were suppressed by coincubation of the mitochondria with cyclosporin A, a typical inhibitor of MPT, showing that diclofenac opened the MPT pore. It was also suggested that reactive oxygen species probably generated during mitochondrial respiration and/or voltage-dependent mechanism was involved in MPT, which are proposed as mechanisms of MPT by uncouplers of mitochondrial oxidative phosphorylation. Culture of hepatocytes for 24 hours with diclofenac caused a decrease in cellular ATP, leakage of lactate dehydrogenase and membrane depolarization. The hepatocyte toxicity thus observed was attenuated by coincubation of the hepatocytes with cyclosporin A and verapamil, a Ca(2+) channel blocker. In conclusion, these results showed the important role of MPT in pathogenesis of hepatocyte injury induced by diclofenac and its possible contribution to human idiosyncratic hepatotoxicity.
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Affiliation(s)
- Yasuhiro Masubuchi
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
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Lee AU, Farrell GC. Mechanism of azathioprine-induced injury to hepatocytes: roles of glutathione depletion and mitochondrial injury. J Hepatol 2001; 35:756-64. [PMID: 11738103 DOI: 10.1016/s0168-8278(01)00196-9] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND/AIMS We sought evidence that azathioprine causes cell death through reduced glutathione (GSH) depletion and mitochondrial injury. METHODS Studies were conducted in primary cultures of rat hepatocytes and cultured Hep G2 cells. RESULTS Azathioprine toxicity to rat hepatocytes was preceded by depletion of GSH. Prior GSH depletion (by treatment with buthionine sulfoximine) enhanced toxicity whilst supplemental GSH or N-acetylcysteine was protective. In hepatocytes, GSH is consumed during metabolism of azathioprine to 6-mercaptopurine. 6-Mercaptopurine was not toxic to hepatocytes, suggesting that the later steps in azathioprine metabolism were not related to the pathogenic mechanism. In Hep G2 cells, azathioprine did not alter levels of GSH and was not toxic. Ultrastructural studies showed hepatocyte mitochondrial lesions after exposure to azathioprine, but no features of apoptosis. Azathioprine produced rapid and profound depletion of adenosine 5'-triphosphate (ATP). Cyclosporin A and glycine afforded protection against azathioprine toxicity, and Trolox and high-dose allopurinol also attenuated injury. CONCLUSIONS The mechanism of azathioprine toxicity to hepatocytes involves depletion of GSH leading to mitochondrial injury with profound depletion of ATP and cell death by necrosis. Cell death was prevented by potent antioxidants, glycine and blocking the mitochondrial permeability transition pore.
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Affiliation(s)
- A U Lee
- Storr Liver Unit, Westmead Millennium Institute, University of Sydney at Westmead Hospital, 2145, Westmead, NSW, Australia
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Blum D, Torch S, Lambeng N, Nissou M, Benabid AL, Sadoul R, Verna JM. Molecular pathways involved in the neurotoxicity of 6-OHDA, dopamine and MPTP: contribution to the apoptotic theory in Parkinson's disease. Prog Neurobiol 2001; 65:135-72. [PMID: 11403877 DOI: 10.1016/s0301-0082(01)00003-x] [Citation(s) in RCA: 890] [Impact Index Per Article: 38.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by a preferential loss of the dopaminergic neurons of the substantia nigra pars compacta. Although the etiology of PD is unknown, major biochemical processes such as oxidative stress and mitochondrial inhibition are largely described. However, despite these findings, the actual therapeutics are essentially symptomatical and are not able to block the degenerative process. Recent histological studies performed on brains from PD patients suggest that nigral cell death could be apoptotic. However, since post-mortem studies do not allow precise determination of the sequence of events leading to this apoptotic cell death, the molecular pathways involved in this process have been essentially studied on experimental models reproducing the human disease. These latter are created by using neurotoxic compounds such as 6-hydroxydopamine (6-OHDA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) or dopamine (DA). Extensive study of these models have shown that they mimick, in vitro and in vivo, the histological and/or the biochemical characteristics of PD and thus help to define important cellular actors of cell death presumably critical for the nigral degeneration. This review reports recent data concerning the biochemical and molecular apoptotic mechanisms underlying the experimental models of PD and correlates them to the phenomena occurring in human disease.
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Affiliation(s)
- D Blum
- Unité Mixte INSERM/UJF E0108, Neurodégénérescence et plasticité, CHU Michallon, Pavillon de Neurologie, BP217, 38043 Cedex 9, Grenoble, France.
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Hu CC, Chen WK, Liao PH, Yu WC, Lee YJ. Synergistic effect of cadmium chloride and acetaldehyde on cytotoxicity and its prevention by quercetin and glycyrrhizin. Mutat Res 2001; 496:117-27. [PMID: 11551487 DOI: 10.1016/s1383-5718(01)00214-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cadmium chloride at concentrations of 10-50mM and acetaldehyde (AA) at 1-5mM showed synergistic toxic effects on V79 cells in vitro. Furthermore, synergistic effects of these chemicals were also observed in mutagenicities of the Hprt gene within certain dose ranges (cadmium chloride 5-10mM, and AA 1-2.5mM). Moreover, lipid peroxide formation, malondialdehyde (MDA) formation, detected by 2-thiobarbituric acid (TBA) reaction and the mitochondrial membrane potentials detected by rhodamine 123 uptake were significantly increased with the combined effect of cadmium and AA in V79. Thus, the cytotoxicity and genotoxicity displayed by combination of these chemicals can be considered to be associated with oxidative stress. Further, these effects were efficiently reduced by quercetin and less efficiently with glycyrrhizin.
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Affiliation(s)
- C C Hu
- Institute of Biochemistry, Chung Shan Medical and Dental College, Taichung, Taiwan, ROC
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Kindmark H, Köhler M, Brown G, Bränström R, Larsson O, Berggren PO. Glucose-induced oscillations in cytoplasmic free Ca2+ concentration precede oscillations in mitochondrial membrane potential in the pancreatic beta-cell. J Biol Chem 2001; 276:34530-6. [PMID: 11445566 DOI: 10.1074/jbc.m102492200] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Using dual excitation and fixed emission fluorescence microscopy, we were able to measure changes in cytoplasmic free Ca(2+) concentration ([Ca(2+)](i)) and mitochondrial membrane potential simultaneously in the pancreatic beta-cell. The beta-cells were exposed to a combination of the Ca(2+) indicator fura-2/AM and the indicator of mitochondrial membrane potential, rhodamine 123 (Rh123). Using simultaneous measurements of mitochondrial membrane potential and [Ca(2+)](i) during glucose stimulation, it was possible to measure the time lag between the onset of mitochondrial hyperpolarization and changes in [Ca(2+)](i). Glucose-induced oscillations in [Ca(2+)](i) were followed by transient depolarizations of mitochondrial membrane potential. These results are compatible with a model in which nadirs in [Ca(2+)](i) oscillations are generated by a transient, Ca(2+)-induced inhibition of mitochondrial metabolism resulting in a temporary fall in the cytoplasmic ATP/ADP ratio, opening of plasma membrane K(ATP) channels, repolarization of the plasma membrane, and thus transient closure of voltage-gated L-type Ca(2+) channels.
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Affiliation(s)
- H Kindmark
- Rolf Luft Center for Diabetes Research, Department of Molecular Medicine, Karolinska Institutet, Karolinska Hospital, S-171 76 Stockholm, Sweden.
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Palomba L, Sestili P, Cantoni O. tert-Butylhydroperoxide induces peroxynitrite-dependent mitochondrial permeability transition leading PC12 cells to necrosis. J Neurosci Res 2001; 65:387-95. [PMID: 11536321 DOI: 10.1002/jnr.1165] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A short-term exposure of PC12 cells to tert-butylhydroperoxide, followed by recovery in fresh culture medium, causes cell death and the extent of this response progressively increases during the 120 min of post-treatment incubation. Morphological and biochemical analyses of these cells revealed that the mode of cell death was necrosis. Cell killing induced by the hydroperoxide seems to be in part mediated by peroxynitrite because the lethal response was markedly and similarly reduced by the nitric oxide synthase inhibitor N omega-nitro-L-arginine methylester and by scavengers of nitric oxide or peroxynitrite. This peroxynitrite-dependent mechanism of cytotoxicity was blunted by antioxidants and inhibitors of mitochondrial permeability transition and the onset of cell death was preceded by mitochondrial depolarization and loss of cellular ATP. We conclude that tert-butylhydroperoxide promotes peroxynitrite-dependent PC12 cell necrosis causally linked to peroxidation of membrane lipids and mitochondrial permeability transition.
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Affiliation(s)
- L Palomba
- Institute of Pharmacology and Pharmacognosy, University of Urbino, Urbino, Italy
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Gómez C, Reiriz J, Piqué M, Gil J, Ferrer I, Ambrosio S. Low concentrations of 1-methyl-4-phenylpyridinium ion induce caspase-mediated apoptosis in human SH-SY5Y neuroblastoma cells. J Neurosci Res 2001; 63:421-8. [PMID: 11223917 DOI: 10.1002/1097-4547(20010301)63:5<421::aid-jnr1037>3.0.co;2-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
There is growing evidence that apoptotic mechanisms underlie the neurodegeneration leading to Parkinson's disease. 1-Methyl-4-phenylpyridinium ion (MPP(+)), the active metabolite of the parkinsonism-inducing drug MPTP, induced apoptosis in cultures of human SH-SY5Y neuroblastoma cells. Nuclear fragmentation, DNA laddering, and a 20% decrease in viability were seen after a 4-day incubation with 5 microM MPP(+). Cell viability decreased by 40% at 100 microM MPP(+), but the degree of apoptosis was not correlatively increased. The MPP(+)-induced apoptosis was completely prevented by the broad caspase inhibitor zVAD.fmk but not by the caspase-8 inhibitor IETD.fmk. Furthermore, MPP(+) had no effect on the levels of Fas or Fas-L, suggesting lack of activation of the Fas-L/Fas/caspase-8 pathway of apoptosis. There was no evidence of mitochondrial dysfunction at 5 microM MPP(+): No differences were seen in transmembrane potential or in cytochrome c release from controls. At 100 microM MPP(+), the mitochondrial potential decreased, and cytoplasmic cytochrome c and caspase-9 activation increased slightly. At both low and high concentrations of MPP(+), VDVADase and DEVDase activities increased. We conclude that MPP(+) can induce caspase-mediated apoptosis, which is prevented by caspase inhibition, at concentrations lower than those needed to trigger mitochondrial dysfunction and closer to those found in the brains of MPTP-treated animals.
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Affiliation(s)
- C Gómez
- Unitat de Bioquímica, Departament de Ciències Fisiològiques II, Universitat de Barcelona, Barcelona, Spain
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Kmonícková E, Drahota Z, Kameníková L, Cervinková Z, Masek K, Farghali H. Modulatory effect of cyclosporin A on tert-butyl hydroperoxide-induced oxidative damage in hepatocytes. Immunopharmacol Immunotoxicol 2001; 23:43-54. [PMID: 11322648 DOI: 10.1081/iph-100102566] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In the present work, we followed an in vitro protective action of cyclosporin A (CsA) against tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in hepatocytes. Various parameters (cell viability, cytosolic calcium level, rhodamine 123 accumulation as indicator of mitochondrial membrane potential and alanine-aminotransferase leakage from cells) were measured as an index of cytotoxicity. Tert-butyl hydroperoxide (1 mM) significantly increased cytosolic Ca2+ and affected mitochondrial membrane potential. Pretreatment with cyclosporin A (0.5 microM) reduced t-BHP-induced cytosolic Ca2+ increase and ALT (alanine-aminotransferase) leakage, but had no protective effect on t-BHP-induced changes of mitochondrial membrane potential. Our data thus suggest that the mechanism of cytoprotection of CsA on the cytosolic Ca2+ changes and ALT leakage induced by t-BHP, does not directly correlate with protection of t-BHP-induced changes of mitochondrial membrane potential.
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Affiliation(s)
- E Kmonícková
- Institute of Pharmacology, 1st Faculty of Medicine, Charles University, Prague, Czech Republic.
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Influence of glutathione on the oxidation chemistry of 5-S-cysteinyldopamine: potentially neuroprotective reactions of relevance to Parkinson's disease. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(00)00953-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Gu L, Miller KE, Dryhurst G. Nigrostriatal dopaminergic neurotoxicity of L-cysteine after stereotaxic administration into the substantia nigra of rats: Potential implications for MPTP-induced neurotoxicity and parkinson’s disease. Neurotox Res 2000. [DOI: 10.1007/bf03033344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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50
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Grub S, Persohn E, Trommer WE, Wolf A. Mechanisms of cyclosporine A-induced apoptosis in rat hepatocyte primary cultures. Toxicol Appl Pharmacol 2000; 163:209-20. [PMID: 10702360 DOI: 10.1006/taap.1999.8887] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In rat hepatocytes and isolated liver mitochondrial fractions, Cyclosporine A (CsA) is often used as a specific inhibitor of mitochondrial Ca(2+) release and as a specific blocker of mitochondrial membrane potential and permeability transition (MPT), which are all processes involved in the inhibition of apoptosis. However, neither inhibition nor induction of apoptosis by CsA has yet been described in the rat hepatocyte primary culture during incubation for 4 and 20 h. It was the purpose of the present study to examine by means of morphological and biochemical criteria the effects of CsA on apoptosis and to characterize the underlying mechanisms. Rat hepatocytes were cultured for 4 or 20 h with CsA at concentrations of 0, 10, 25, and 50 microM. Chromatin condensation and fragmentation, DNA fragmentation (TUNEL), membrane phosphatidylserine distribution (Annexin V), caspase-1, -3, and -6 activity, mitochondrial membrane potential (Rhodamine 123), and cytochrome c release into the cytosol were investigated. Four hours after CsA treatment, chromatin condensation and fragmentation and the number of TUNEL- and Annexin V-positive cells increased dose-dependently without any observable enzyme leakage, which indicated the integrity of the outer cell membrane. After 20 h of CsA incubation apoptosis parameters were further increased and were accompanied by the increased activity of the cysteine protease, caspase-3 (CPP 32), and slightly increased caspase-6 (Mch 2), but not caspase-1 (ICE). The caspase-3 inhibitor, Ac-DEVD-CHO, inhibited caspase-3 activation and attenuated CsA-induced apoptosis and LDH leakage. The caspase-6 inhibitor, Ac-VEID-CHO, only marginally inhibited CsA-induced apoptosis. Decreased mitochondrial membrane potential and cytochrome c release went in parallel with ultrastructural mitochondrial changes and might be regarded as early events that trigger the apoptosis cascade. Transmission electron microscopy confirmed an increase in the number of necrotic cells after 20 h, but not after 4 h, compared with controls.
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Affiliation(s)
- S Grub
- Experimental Toxicology, Novartis Pharma AG, Basel, CH-4002, Switzerland
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