1
|
Majumder A, Singh M, George AK, Tyagi SC. Restoration of skeletal muscle homeostasis by hydrogen sulfide during hyperhomocysteinemia-mediated oxidative/ER stress condition 1. Can J Physiol Pharmacol 2018; 97:441-456. [PMID: 30422673 DOI: 10.1139/cjpp-2018-0501] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Elevated homocysteine (Hcy), i.e., hyperhomocysteinemia (HHcy), causes skeletal muscle myopathy. Among many cellular and metabolic alterations caused by HHcy, oxidative and endoplasmic reticulum (ER) stress are considered the major ones; however, the precise molecular mechanism(s) in this process is unclear. Nevertheless, there is no treatment option available to treat HHcy-mediated muscle injury. Hydrogen sulfide (H2S) is increasingly recognized as a potent anti-oxidant, anti-apoptotic/necrotic/pyroptotic, and anti-inflammatory compound and also has been shown to improve angiogenesis during ischemic injury. Patients with CBS mutation produce less H2S, making them vulnerable to Hcy-mediated cellular damage. Many studies have reported bidirectional regulation of ER stress in apoptosis through JNK activation and concomitant attenuation of cell proliferation and protein synthesis via PI3K/AKT axis. Whether H2S mitigates these detrimental effects of HHcy on muscle remains unexplored. In this review, we discuss molecular mechanisms of HHcy-mediated oxidative/ER stress responses, apoptosis, angiogenesis, and atrophic changes in skeletal muscle and how H2S can restore skeletal muscle homeostasis during HHcy condition. This review also highlights the molecular mechanisms on how H2S could be developed as a clinically relevant therapeutic option for chronic conditions that are aggravated by HHcy.
Collapse
Affiliation(s)
- Avisek Majumder
- a Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA.,b Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Mahavir Singh
- a Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA.,c Eye and Vision Science Laboratory, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Akash K George
- a Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA.,c Eye and Vision Science Laboratory, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Suresh C Tyagi
- a Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
| |
Collapse
|
2
|
Carrasco-Pozo C, Alvarez-Lueje A, Olea-Azar C, López-Alarcón C, Speisky H. In Vitro Interaction Between Homocysteine and Copper Ions: Potential Redox Implications. Exp Biol Med (Maywood) 2016; 231:1569-75. [PMID: 17018882 DOI: 10.1177/153537020623100918] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Homocysteine (Hcys) has been implicated in various oxidative stress-related disorders. The presence of a thiol on its structure allows Hcys to exert a double-edge redox action. Depending on whether Cu2+ ions occur concomitantly, Hcys can either promote or prevent free radical generation and its consequences. We have addressed In vitro the interaction between Hcys and Cu2+ Ions, in terms of the consequences that such interaction may have on the free radical scavenging properties of Hcys and on the redox state and redox activity of the metal. To this end, we investigated the free radical-scavenging, O2--generating, and ascorbate-oxidizing properties of the interacting species by assessing the bleaching of ABTS'+ radicals, the reduction of O2--dependent cytochrome c, and the copper-dependent oxidation of ascorbate, respectively. In addition, electron paramagnetic resonance and Cu(I)-bathocuproine formation were applied to assess the formation of paramagnetic complexes and the metal redox state. Upon a brief incubation, the Hcys/Cu2+ Interaction led to a decrease in the free radical-scavenging properties of Hcys, and to a comparable loss of the thiol density. Both effects were partial and were not modified by increasing the Incubation time, despite the presence of Cu2+ excess. Depending on the molar Hcys : Cu2+ ratio, the interaction resulted in the formation of mixtures that appear to contain time-stable and ascorbate-reducible Cu(II) complexes (for ratios up to 2:1), and ascorbate- and oxygen-redox-inactive Cu(l) complexes (for ratios up to 4:1). Increasing the interaction ratio beyond 4:1 was associated with the sudden appearance of an O2--generating activity. The data indicate that depending on the molar ratio of interaction, Hcys and Cu2+ react to form copper complexes that can promote either antioxidant or pro-oxidant actions. We speculate that the redox activity arising from a large molar Hcys excess may partially underlie the association between hyper-homocysteinemia and a greater risk of developing oxidative-related cardiovascular diseases.
Collapse
Affiliation(s)
- Catalina Carrasco-Pozo
- Miconutrients Unit, Nutrition and Food Technology Institute (INTA), University of Chile, El Líbano 5524, Macul, PO Box 138-11, Santiago, Chile
| | | | | | | | | |
Collapse
|
3
|
Bao XM, Wu CF, Lu GP. Atorvastatin attenuates homocysteine-induced apoptosis in human umbilical vein endothelial cells via inhibiting NADPH oxidase-related oxidative stress-triggered p38MAPK signaling. Acta Pharmacol Sin 2009; 30:1392-8. [PMID: 19767766 DOI: 10.1038/aps.2009.135] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
AIM To examine the effect of atorvastatin on homocysteine (Hcy)-induced reactive oxygen species (ROS) production and apoptosis in human umbilical vein endothelial cells (HUVECs). METHODS HUVECs were cultured with Hcy (0.1-5 mmol/L) in the presence or absence of atorvastatin (1-100 micromol//L) or various stress signaling inhibitors, including the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor diphenylene iodonium (DPI, 10 micromol/L), the p38 mitogen-activated protein kinase (p38 MAPK) inhibitor SB203580 (10 micromol/L) and antioxidants N-acetyl cysteine (NAC, 1 mmol/L). Cell apoptosis was evaluated by Annexin V/propidium iodide staining and flow cytometry. ROS were detected by 2',7'-dichlorodihydrofluorescein diacetate (H(2)DCFH-DA). NADPH oxidases were evaluated with lucigenin-enhanced chemiluminescence. Hcy-induced expression of p38MAPK protein was measured by Western blotting analysis. RESULTS Atorvastatin inhibited endothelial cell apoptosis induced by 1 mmol/L Hcy in a dose-dependent manner and the maximal inhibitory effect was reached at 100 micromol/L. Atorvastatin (10 micromol/L) significantly suppressed Hcy (1 mmol/L for 30 min) induced ROS accumulation (3.17+/-0.33 vs 4.34+/-0.31, P<0.05). Atorvastatin (10 micromol/L) also antagonized Hcy (1 mmol/L for 30 min) induced activation of NADPH oxidase (2.57+/-0.49 vs 3.33+/-0.6, P<0.05). Furthermore, atorvastatin inhibited Hcy-induced phosphorylation of p38 MAPK (1.7+/-0.1 vs 2.22+/-0.25, P<0.05), similar effects occurred with DPI, NAC and SB203580. CONCLUSION Atorvastatin may inhibit Hcy-induced ROS accumulation and endothelium cell apoptosis through an NADPH oxidase and/or p38MAPK-dependent mechanisms, all of which may contribute to atorvastatin-induced beneficial effect on endothelial function.
Collapse
|
4
|
Nickel T, Deutschmann A, Hanssen H, Summo C, Wilbert-Lampen U. Modification of endothelial biology by acute and chronic stress hormones. Microvasc Res 2009; 78:364-9. [PMID: 19664643 DOI: 10.1016/j.mvr.2009.07.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 07/02/2009] [Accepted: 07/31/2009] [Indexed: 01/07/2023]
Abstract
OBJECTIVE An increasing number of studies have examined the role of emotional stress and coronary heart disease; the underlying pathophysiology is still poorly understood. The present study was designed to evaluate the relationship between acute (epi- and norepinephrine) and chronic stress hormones (dexamethasone, beta-endorphin, corticotropin releasing hormone) and endothelial dysfunction. METHODS Human microvascular endothelial cells were incubated with stress hormones for 6 and 24 h. ET-1 release and ADMA were quantified via ELISA, NO release by using cell permeable 4.5-diaminofluorescein diacetate (DAF2-DA), oxidative stress fluometrically by the ROS-sensitive carboxy-H2-DCFDA method, mitochondrial metabolic activity by using the colorimetric assay WST-1, ET-1 receptor type A (ET(A)R) protein expression by Western blot, and cell proliferation activity was assessed by the colorimetric assay BrdU. RESULTS With respect to analysed acute and chronic stress hormones, ET-1 release was significantly increased. Likewise, protein expression was enhanced after long term incubation (24 h) with norepinephrine and dexamethasone. In contrast, endothelial NO-levels were only influenced by short term stimulation of dexamethasone (upregulation of NO release) and norepinephrine (downregulation of NO release), whereas modified NO concentration mimics altered mitochondrial metabolic activity. Unexpectedly, both oxidative stress and cell proliferation were not modified by stress hormones. CONCLUSION Results suggest that acute and chronic stress hormones induce a significant ET-1 release whereas NO release remained mainly unchanged. The imbalance of pro- and antiatherosclerotic factors may play a pivotal role in the initiation of stress-related endothelial dysfunction up to myocardial infarction.
Collapse
Affiliation(s)
- T Nickel
- Medizinische Klinik und Poliklinik I, Campus Grosshadern, Ludwig-Maximilians-Universität, München, Germany.
| | | | | | | | | |
Collapse
|
5
|
Homocysteine is a potent modulator of plasma membrane electron transport systems. J Bioenerg Biomembr 2008; 40:45-51. [DOI: 10.1007/s10863-008-9127-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2007] [Accepted: 11/12/2007] [Indexed: 12/22/2022]
|
6
|
Martignoni E, Tassorelli C, Nappi G, Zangaglia R, Pacchetti C, Blandini F. Homocysteine and Parkinson's disease: a dangerous liaison? J Neurol Sci 2007; 257:31-7. [PMID: 17336337 DOI: 10.1016/j.jns.2007.01.028] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Homocysteine, a sulphur-containing amino acid formed by demethylation of methionine, is involved in numerous processes of methyl group transfer, all playing pivotal roles in the biochemistry of the human body. Increased levels of plasma homocysteine (hyperhomocysteinemia) - which may result from a deficiency of folate, vitamin B6 or B12 or mutations in enzymes regulating the catabolism of homocysteine - are associated with a wide range of clinical manifestations, mostly affecting the central nervous system (e.g., mental retardation, cerebral atrophy and epileptic seizures). Recent evidence suggests that changes in the metabolic fate of homocysteine, leading to hyperhomocysteinemia, may also play a role in the pathophysiology of neurodegenerative disorders, particularly Parkinson's disease (PD). The nervous system might be particularly sensitive to homocysteine, due to the excitotoxic-like properties of the amino acid. However, experimental findings have shown that homocysteine does not seem to posses direct, cytotoxic activity, while the amino acid has proven able to synergize with more specific neurotoxic insults. Hyperhomocysteinemia has been repeatedly reported in PD patients; the increase, however, seems mostly related to the methylated catabolism of l-Dopa, the main pharmacological treatment of PD. Therefore, hyperhomocysteinemia may not be specific to movement disorders or other neurological diseases, the condition being, in fact, rather the result of the combinations of different factors, mainly metabolic, but also genetic and pharmacological, intervening in the neurodegenerative process.
Collapse
Affiliation(s)
- E Martignoni
- IRCCS S. Maugeri Foundation, Scientific Institute of Veruno, Via per Revislate 13, 28010 Veruno (NO), Italy.
| | | | | | | | | | | |
Collapse
|
7
|
Kerkeni M, Tnani M, Chuniaud L, Miled A, Maaroufi K, Trivin F. Comparative study on in vitro effects of homocysteine thiolactone and homocysteine on HUVEC cells: evidence for a stronger proapoptotic and proinflammative homocysteine thiolactone. Mol Cell Biochem 2006; 291:119-26. [PMID: 16715183 DOI: 10.1007/s11010-006-9204-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2005] [Accepted: 03/28/2006] [Indexed: 11/28/2022]
Abstract
Hyperhomocysteinemia is an independent risk factor for the development of atherosclerosis. However the underlying mechanisms responsible for endothelial cell injury with increased plasma concentration of homocysteine or homocysteine derivatives remains still incompletely elucidated. In this study, we investigated the ability of homocysteine (Hcy) and homocysteine thiolactone (HcyT) to induce cell death and IL-8 secretion in primary human umbilical vein endothelial cells (HUVEC). Hcy and HcyT were both cytotoxic and capable of promoting cell death, as measured by caspase-3 activation and DNA fragmentation. ELISA assays clearly demonstrated that Hcy and HcyT strongly activated IL-8 release. Furthermore, our results showed that HcyT was much more efficient than Hcy in activating caspase-3 or in inducing IL-8 secretion. The use of antioxidants such as vitamin C and vitamin E strongly but not completely reduced programmed cell death and chemokine release suggesting that other pathways different than reactive oxygen species are also involved. This study suggests that Homocysteine derivatives like HcyT might possess stronger cytotoxicity and pro-inflammatory properties and that Hcy derivatives levels should therefore be more taken into account during diagnostics.
Collapse
Affiliation(s)
- Mohsen Kerkeni
- Research Unit 03/UR/08-14, Faculty of Pharmacy, Monastir, Tunisia.
| | | | | | | | | | | |
Collapse
|
8
|
González-Santiago L, Suárez Y, Zarich N, Muñoz-Alonso MJ, Cuadrado A, Martínez T, Goya L, Iradi A, Sáez-Tormo G, Maier JV, Moorthy A, Cato ACB, Rojas JM, Muñoz A. Aplidin® induces JNK-dependent apoptosis in human breast cancer cells via alteration of glutathione homeostasis, Rac1 GTPase activation, and MKP-1 phosphatase downregulation. Cell Death Differ 2006; 13:1968-81. [PMID: 16543941 DOI: 10.1038/sj.cdd.4401898] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Aplidin is an antitumor agent in phase II clinical trials that induces apoptosis through the sustained activation of Jun N-terminal kinase (JNK). We report that Aplidin alters glutathione homeostasis increasing the ratio of oxidized to reduced forms (GSSG/GSH). Aplidin generates reactive oxygen species and disrupts the mitochondrial membrane potential. Exogenous GSH inhibits these effects and also JNK activation and cell death. We found two mechanisms by which Aplidin activates JNK: rapid activation of Rac1 small GTPase and downregulation of MKP-1 phosphatase. Rac1 activation was diminished by GSH and enhanced by L-buthionine (SR)-sulfoximine, which inhibits GSH synthesis. Downregulation of Rac1 by transfection of small interfering RNA (siRNA) duplexes or the use of a specific Rac1 inhibitor decreased Aplidin-induced JNK activation and cytotoxicity. Our results show that Aplidin induces apoptosis by increasing the GSSG/GSH ratio, a necessary step for induction of oxidative stress and sustained JNK activation through Rac1 activation and MKP-1 downregulation.
Collapse
Affiliation(s)
- L González-Santiago
- Instituto de Investigaciones Biomédicas 'Alberto Sols', Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Arturo Duperier, 4, Madrid E-28029, Spain
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Sakuta H, Suzuki T, Yasuda H, Ito T. Gamma-glutamyl transferase and metabolic risk factors for cardiovascular disease. Intern Med 2005; 44:538-41. [PMID: 16020876 DOI: 10.2169/internalmedicine.44.538] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVE To elucidate the mechanism of the reported association between serum gamma-glutamyl transferase (GGT) activity and cardiovascular mortality. METHODS Cross-sectional analysis of the relationship between serum GGT activity and the risk factors for cardiovascular disease was performed. PATIENTS AND MATERIALS Middle-aged Japanese male personnel of the Self-Defense Forces who underwent retirement check-up. RESULTS Serum GGT activity was associated with total cholesterol, triglyceride, fasting plasma glucose, total homocysteine and systolic blood pressure. The association remained in the analysis adjusted for possible confounders including cigarette smoking, ethanol consumption and body mass index. CONCLUSION The observed association between serum GGT and cardiovascular risk factors may partly explain the reported relationship between serum GGT activity and cardiovascular disease. Serum GGT activity may be regarded as a marker of cardiovascular risk factors or oxidative stress rather than a mere indicator of excessive ethanol consumption or obesity.
Collapse
Affiliation(s)
- Hidenari Sakuta
- Department of Internal Medicine, Self-Defense Forces Central Hospital, Tokyo
| | | | | | | |
Collapse
|
10
|
Lee SJ, Kim KM, Namkoong S, Kim CK, Kang YC, Lee H, Ha KS, Han JA, Chung HT, Kwon YG, Kim YM. Nitric Oxide Inhibition of Homocysteine-induced Human Endothelial Cell Apoptosis by Down-regulation of p53-dependent Noxa Expression through the Formation of S-Nitrosohomocysteine. J Biol Chem 2005; 280:5781-8. [PMID: 15561702 DOI: 10.1074/jbc.m411224200] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Hyperhomocysteinemia is believed to induce endothelial dysfunction and promote atherosclerosis; however, the pathogenic mechanism has not been clearly elucidated. In this study, we examined the molecular mechanism by which homocysteine (HCy) causes endothelial cell apoptosis and by which nitric oxide (NO) affects HCy-induced apoptosis. Our data demonstrated that HCy caused caspase-dependent apoptosis in cultured human umbilical vein endothelial cells, as determined by cell viability, nuclear condensation, and caspase-3 activation and activity. These apoptotic characteristics were correlated with reactive oxygen species (ROS) production, lipid peroxidation, p53 and Noxa expression, and mitochondrial cytochrome c release following HCy treatment. HCy also induced p53 and Noxa expression and apoptosis in endothelial cells from wild type mice but not in the p53-deficient cells. The NO donor S-nitroso-N-acetylpenicillamine, adenoviral transfer of inducible NO synthase gene, and antioxidants (alpha-tocopherol and superoxide dismutase plus catalase) but not oxidized SNAP, 8-Br-cGMP, nitrite, and nitrate, suppressed ROS production, p53-dependent Noxa expression, and apoptosis induced by HCy. The cytotoxic effect of HCy was decreased by small interfering RNA-mediated suppression of Noxa expression, indicating that Noxa up-regulation plays an important role in HCy-induced endothelial cell apoptosis. Overexpression of inducible NO synthase increased the formation of S-nitroso-HCy, which was inhibited by the NO synthase inhibitor N-monomethyl-l-arginine. Moreover, S-nitroso-HCy did not increase ROS generation, p53-dependent Noxa expression, and apoptosis. These results suggest that up-regulation of p53-dependent Noxa expression may play an important role in the pathogenesis of atherosclerosis induced by HCy and that an increase in vascular NO production may prevent HCy-induced endothelial dysfunction by S-nitrosylation.
Collapse
Affiliation(s)
- Seon-Jin Lee
- Vascular System Research Center and Department of Molecular and Cellular Biochemistry, School of Medicine, Kangwon National University, Chunchon, Kangwon-do 200-701, Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Chan K, Chui SH, Wong DYL, Ha WY, Chan CL, Wong RNS. Protective effects of Danshensu from the aqueous extract of Salvia miltiorrhiza (Danshen) against homocysteine-induced endothelial dysfunction. Life Sci 2005; 75:3157-71. [PMID: 15488895 DOI: 10.1016/j.lfs.2004.06.010] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2003] [Accepted: 06/14/2004] [Indexed: 12/19/2022]
Abstract
Homocysteine (Hcy) is a by-product of methionine metabolism. An imbalance of Hcy in the body may lead to hyperhomocysteinemia, a condition with elevated Hcy concentration in blood that may be one of the risk factors responsible for the development of several vascular diseases (thromboembolism, atherosclerosis, stroke, vascular diseases and dementia). Radix Salvia miltiorrhiza (Danshen), a well-known Chinese medicinal herb that can activate and improve blood microcirculation, is noticeable for its beneficial effect in treating cardiovascular diseases. The present study is to demonstrate the protective effect of Danshen extract against the homocysteine-induced adverse effect on human umbilical vein endothelial cell (HUVEC). Homocysteine (5 mM) not only decreased the cell viability but also caused the disruption of capillary-like structure formation in vitro. The protective effect of Danshen aqueous extract and its active compounds on endothelial cell function were demonstrated through an in vitro tube formation assay, which mimics the new blood vessel formation. To identify the active components in the aqueous extract of Danshen, the content was characterized by instrumental analysis using high performance liquid chromatography with diode array detector (DAD) and electrospray tandem mass spectrometry (ESI-MS/MS). Interestingly, Danshen extract and its pure compounds showed different effectiveness in protecting HUVEC against Hcy-induced injury according to the following descending order: Danshen aqueous extract, 3-(3,4-dihydroxy-phenyl)-2-hydroxy-propionic acid (Danshensu), protocatechuic acid, catechin and protocatechualdehyde. We believed that such findings might provide evidence in understanding the beneficial effects of Danshen on the cardiovascular system.
Collapse
Affiliation(s)
- K Chan
- Research and Development Division, School of Chinese Medicine, Hong Kong Baptist University, Hong Kong
| | | | | | | | | | | |
Collapse
|
12
|
Bleich S, Degner D, Sperling W, Bönsch D, Thürauf N, Kornhuber J. Homocysteine as a neurotoxin in chronic alcoholism. Prog Neuropsychopharmacol Biol Psychiatry 2004; 28:453-64. [PMID: 15093951 DOI: 10.1016/j.pnpbp.2003.11.019] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/14/2003] [Indexed: 11/28/2022]
Abstract
There is evidence from in vitro and in vivo studies that homocysteine induces neuronal damage and cell loss by both excitotoxicity and different apoptotic processes. Clinical evidence suggest a strong relationship between higher plasma homocysteine levels and brain atrophy in healthy elderly subjects as well as in elderly at risk of and with Alzheimer's disease. Chronic alcoholism leads to elevated plasma homocysteine levels, as shown by clinical investigations and animal experiments. In addition, an association between brain atrophy and increased levels of homocysteine in chronic alcoholism was shown. This may have important implications for the pathogenesis of alcoholism-associated brain atrophy. Furthermore, taking into account that high plasma homocysteine levels are helpful in the prediction of alcohol withdrawal seizures, early anticonvulsive therapy could prevent this severe complication. Homocysteine plays a role in a shared biochemical cascade involving overstimulation of N-methyl-D-aspartate (NMDA) receptors, oxidative stress, activation of caspases, DNA damage, endoplasmic reticulum and mitochondrial dysfunction. These mechanisms are believed to be important in the pathogenesis of both excitotoxicity and apoptotic neurotoxicity. Prospective intervention studies may show whether the incidence of complications of alcohol withdrawal or alcoholism-associated disorders can be reduced by therapeutic measures with early lowering of elevated homocysteine levels (e.g. folate administration). The most important pathophysiological and pathobiochemical features of glutamatergic neurotransmission and of ethanol-induced hyperhomocysteinaemia are reviewed in relation to their excitotoxic and apoptotic potential.
Collapse
Affiliation(s)
- Stefan Bleich
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander University of Erlangen-Nuremberg, Schwabachanlage 6-10, Erlangen 91054, Germany.
| | | | | | | | | | | |
Collapse
|
13
|
Mangiagalli A, Samuele A, Armentero MT, Bazzini E, Nappi G, Blandini F. Effects of homocysteine on apoptosis-related proteins and anti-oxidant systems in isolated human lymphocytes. ACTA ACUST UNITED AC 2004; 271:1671-6. [PMID: 15096206 DOI: 10.1111/j.1432-1033.2004.04070.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Homocysteine (Hcy) is a nonprotein-forming sulphur amino acid that plays an important role in remethylation and trans-sulphuration processes. In recent years, it has been suggested that increased levels of plasma Hcy may play a role in the pathogenesis of various diseases, particularly at the cardiovascular level. The pathogenic mechanism of hyperhomocysteinemia, however, has not been clarified. Because oxygen radicals can be generated by the auto-oxidation of this amino acid, it has been suggested that Hcy may cause cellular damage through oxidative mechanisms, ultimately leading to apoptotic cell death. In this study, we sought to investigate the effects of Hcy on oxidative damage and antioxidant agent levels, as well as on apoptosis-related proteins and apoptosis occurrence in human cells. For this purpose, we measured levels of Bcl-2, caspase-3 and caspase-9 activity, Cu/Zn superoxide dismutase, reduced glutathione, lipid peroxidation [malondialdehyde and 4-hydroxy-2 (E)-nonenal concentrations], apoptotic single-stranded DNA and nuclear changes in human isolated lymphocytes exposed to increasing concentrations of Hcy. Incubation with Hcy did not induce significant changes in any of these biomarkers. Therefore, our results do not support the existence of a direct link between increased levels of Hcy and the occurrence of a pro-apoptotic state mediated by enhanced oxidative stress.
Collapse
Affiliation(s)
- Anna Mangiagalli
- Laboratory of Functional Neurochemistry, Neurological Institute C. Mondino, Pavia, Italy
| | | | | | | | | | | |
Collapse
|
14
|
Suhara T, Fukuo K, Yasuda O, Tsubakimoto M, Takemura Y, Kawamoto H, Yokoi T, Mogi M, Kaimoto T, Ogihara T. Homocysteine enhances endothelial apoptosis via upregulation of Fas-mediated pathways. Hypertension 2004; 43:1208-13. [PMID: 15117910 DOI: 10.1161/01.hyp.0000127914.94292.76] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hyperhomocysteinemia is an independent risk factor for the development of atherosclerosis. However, the underlying mechanism of endothelial cell injury in hyperhomocysteinemia has not been elucidated. In this study, we examined the effect of homocysteine (Hcy) on Fas-mediated apoptosis in endothelial cells. Hcy-induced upregulation of Fas in endothelial cells (ECs) in a dose-dependent manner. At the same time, Hcy increased intracellular peroxide in ECs. Hcy-induced Fas expression was inhibited by the treatment with catalase. Hcy increased NF-kappaB DNA binding activity, and adenovirus-mediated transfection of a Ikappa-B mutant (Ikappa-B mt) gene inhibited Hcy-induced Fas expression. ECs were sensitive to Fas-mediated apoptosis when exposed to Hcy. Under these condition, Ikappa-B mt protected ECs from Fas-mediated apoptosis. In addition, Hcy inhibited expression of the caspase-8 inhibitor FLICE-inhibitory protein (FLIP). Adenovirus-mediated transfection of constitutively active Akt gene abolished the Hcy-mediated downregulation of FLIP. These data suggest that upregulation of Fas expression and downregulation of FLIP is a mechanism through which Hcy induces EC apoptosis.
Collapse
Affiliation(s)
- Toshimitsu Suhara
- Department of Geriatric Medicine, Osaka University Medical School, Suita, Osaka, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Mechiche H, Candenas L, Pinto FM, Nazeyrollas P, Clément C, Devillier P. Characterization of cysteinyl leukotriene receptors on human saphenous veins: antagonist activity of montelukast and its metabolites. J Cardiovasc Pharmacol 2004; 43:113-20. [PMID: 14668576 DOI: 10.1097/00005344-200401000-00017] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The aims of this study were to determine the cysteinyl leukotriene (CysLT) receptors expressed in the human saphenous vein, to examine contractile response to LTC4 and LTD4, to evaluate antagonist activity of montelukast, a specific CysLT1 receptor antagonist used in asthma, and to characterize the CysLT receptors involved in the contractile response. The analysis by reverse-transcriptase polymerase chain reaction indicated that CysLT1 and CysLT2 receptors are expressed by saphenous veins. In varicose vein rings, the potencies (pD2) of LTC4 and LTD4 were similar: 7.4 +/- 0.2 and 7.4 +/- 0.1, respectively. Pretreatment with acivicin, a gamma-glutamyl transpeptidase (gamma-GT) inhibitor, to prevent potential metabolism of LTC4 to LTD4, did not alter the response to LTC4. In nondistended vein rings from patients undergoing arterial bypass, the LTC4 pD2 was 7.8 +/- 0.1, and pretreatment with S-hexyl-GSH, a potent gamma-GT inhibitor, caused a fourfold rightward shift of the LTC4 concentration-response curve. In varicose and nondistended saphenous vein rings, montelukast (10(-8) and 10(-7) M) exerted a potent activity against LTD4 and LTC4, in the presence or absence of gamma-GT inhibitors. In varicose vein rings, the two active metabolites of montelukast also exerted antagonist activities with potencies similar to montelukast. BAY u9773 (CysLT2 agonist/dual CysLT1/CysLT2 antagonist) did not cause contraction and inhibited the LTC4- and LTD4-induced contractions. In conclusion, human saphenous veins express CysLT1 and CysLT2 receptors, but only CysLT1 receptors are implicated in the contraction.
Collapse
Affiliation(s)
- Hakima Mechiche
- Laboratory of Pharmacology, Faculty of Medicine, University Hospital, Reims, France
| | | | | | | | | | | |
Collapse
|
16
|
Di Simone N, Maggiano N, Caliandro D, Riccardi P, Evangelista A, Carducci B, Caruso A. Homocysteine induces trophoblast cell death with apoptotic features. Biol Reprod 2003; 69:1129-34. [PMID: 12773435 DOI: 10.1095/biolreprod.103.015800] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Hyperhomocysteinemia has been suggested as a possible risk factor in women suffering from habitual abortions, placental abruption or infarcts, preeclampsia, and/or intrauterine growth retardation. However, little is known about the pathogenic mechanisms underlying the action of homocysteine. The present study investigated the in vitro ability of homocysteine to affect trophoblast gonadotropin secretion and to induce cell death. In primary human trophoblast cells, homocysteine treatment (20 micromol/L) resulted in cellular flattening and enlargement, extension of pseudopodia, and cellular vacuolization. Cellular detachment, apoptosis, and necrosis were favored. With in situ nick end labeling, we investigated DNA degradation, and we used M30 CytoDEATH to selectively stain the cytoplasm of apoptotic cells. Cytochrome c release from mitochondria to the cytosol and DNA cleavage in agarose gel have been investigated. Homocysteine, but not cysteine, induced trophoblast apoptosis and significantly reduced human chorionic gonadotropin secretion. These findings suggest that trophoblast cell death might represent a pathogenic mechanism by which homocysteine may cause pregnancy complications related to placental diseases.
Collapse
Affiliation(s)
- Nicoletta Di Simone
- Department of Obstetrics and Gynecology, Catholic University of Sacred Heart, 00168 Rome, Italy
| | | | | | | | | | | | | |
Collapse
|
17
|
Radyuk SN, Sohal RS, Orr WC. Thioredoxin peroxidases can foster cytoprotection or cell death in response to different stressors: over- and under-expression of thioredoxin peroxidase in Drosophila cells. Biochem J 2003; 371:743-52. [PMID: 12556226 PMCID: PMC1223337 DOI: 10.1042/bj20021522] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2002] [Revised: 01/28/2003] [Accepted: 01/30/2003] [Indexed: 12/20/2022]
Abstract
Recently, we identified a set of five genes constituting the peroxiredoxin gene family in Drosophila melanogaster [Radyuk, Klichko, Spinola, Sohal and Orr (2001) Free Radical Biol. Med. 31, 1090-1100]. This set includes two abundant thioredoxin peroxidase (TPx) species, namely Drosophila peroxiredoxin DPx-4783, a cytosolic TPx and DPx-5037, a mitochondrial TPx. Overexpression of either one of them in Drosophila S2 cells conferred increased resistance to toxicity induced by hydrogen peroxide, paraquat or cadmium. To understand further the functional roles of these enzymes in vivo, we report in the present study the effects of decreased expression, using RNA interference, on the response of S2 cells to different stressors. When either of the TPxs was blocked, cells became relatively more susceptible to oxidative stress caused by exposure to hydrogen peroxide or paraquat, but were unaffected when challenged with copper and heat stress. In contrast, TPx overexpressing cells were more susceptible to copper and heat stress when compared with control cells and exhibited DNA fragmentation. Furthermore, when cells were supplemented with N -acetyl-L-cysteine together with copper, there was a clear negative effect on cell survival, which was exacerbated by TPx overexpression. Manipulations in the levels of TPxs demonstrated that, under different stress conditions, these enzymes might have both beneficial and detrimental effects on Drosophila cell viability.
Collapse
Affiliation(s)
- Svetlana N Radyuk
- Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275, USA
| | | | | |
Collapse
|
18
|
Chavarría T, Rodríguez-Nieto S, Sánchez-Jiménez F, Quesada AR, Medina MA. Homocysteine is a potent inhibitor of human tumor cell gelatinases. Biochem Biophys Res Commun 2003; 303:572-5. [PMID: 12659857 DOI: 10.1016/s0006-291x(03)00382-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Extracellular matrix-degrading gelatinases are mainly involved in tumor invasion and metastasis. Previous experimental data from our group and others suggested that homocysteine could have a potential modulatory role on the proteolytic balance at the extracellular matrix. Therefore, we studied the effects of homocysteine on extracellular matrix-degrading proteases using model human tumor cell lines and a combination of in vitro fluorogenic assay and zymographic techniques. Homocysteine is shown to be the thiol compound with the most potent inhibitory activity on matrix metalloproteinase 9. Zymographies reveal that matrix metalloproteinase 2 is, at least, as sensitive to inhibition by homocysteine as matrix metalloproteinase 9 is. This study opens new ways to the potential pharmacological use of thiol compounds.
Collapse
Affiliation(s)
- Teresa Chavarría
- Department of Molecular Biology and Biochemistry, Faculty of Sciences, University of Málaga, E-29071 Málaga, Spain
| | | | | | | | | |
Collapse
|
19
|
Chavarría T, Sánchez-Jiménez F, Quesada AR, Medina MA. Homocysteine inhibits the proliferation and invasive potential of HT-1080 human fibrosarcoma cells. Biochem Biophys Res Commun 2003; 301:540-4. [PMID: 12565896 DOI: 10.1016/s0006-291x(02)03081-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The impairment of homocysteine metabolism has been related to several disorders and diseases. Recently, homocysteine has been shown to inhibit key steps of angiogenesis, including endothelial cell proliferation, invasion, and remodeling of the extracellular matrix. Since these are also key steps in tumor invasion and metastasis, it can be hypothesized that homocysteine can also interfere in these processes. Therefore, we studied the effects of homocysteine on tumor proliferation and invasion, as well as on urokinase, a key extracellular matrix-degrading protease, using a model human tumor cell line. This study demonstrates that, in fact, homocysteine inhibits HT-1080 proliferation and invasion, and is a potent inhibitor of tumor cell urokinase expression.
Collapse
Affiliation(s)
- T Chavarría
- Department of Molecular Biology and Biochemistry, Faculty of Sciences, University of Málaga, E-29071 Málaga, Spain
| | | | | | | |
Collapse
|
20
|
Knott L, Hartridge T, Brown NL, Mansell JP, Sandy JR. Homocysteine oxidation and apoptosis: a potential cause of cleft palate. In Vitro Cell Dev Biol Anim 2003; 39:98-105. [PMID: 12892533 DOI: 10.1290/1543-706x(2003)039<0098:hoaaap>2.0.co;2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cleft palate is the most common craniofacial anomaly. Affected individuals require extensive medical and psychosocial support. Although cleft palate has a complex and poorly understood etiology, low maternal folate is known to be a risk factor for craniofacial anomalies. Folate deficiency results in elevated homocysteine levels, which may disturb palatogenesis by several mechanisms, including oxidative stress and perturbation of matrix metabolism. We examined the effect of homocysteine-induced oxidative stress on human embryonic palatal mesenchyme (HEPM) cells and demonstrated that biologically relevant levels of homocysteine (20-100 microM) with copper (10 microM) resulted in dose-dependent apoptosis, which was prevented by addition of catalase but not superoxide dismutase. Incubation of murine palates in organ culture with homocysteine (100 micro) and CuSO(4) (10 microM) resulted in a decrease in palate fusion, which was not significant. Gelatin gel zymograms of HEPM cell-conditioned media and extracts of cultured murine palates, however, showed no change in the expression or activation of pro-matrix metalloproteinase-2 with homocysteine (20 microM-1 mM) with or without CuSO(4) (10 microM). We have demonstrated that biologically relevant levels of homocysteine in combination with copper can result in apoptosis as a result of oxidative stress; therefore, homocysteine has the potential to disrupt normal palate development.
Collapse
Affiliation(s)
- Lynda Knott
- Division of Child Dental Health, Dental School, University of Bristol, United Kingdom BS1 2LY.
| | | | | | | | | |
Collapse
|
21
|
Rodríguez-Nieto S, Chavarría T, Martínez-Poveda B, Sánchez-Jiménez F, Rodríguez Quesada A, Medina MA. Anti-angiogenic effects of homocysteine on cultured endothelial cells. Biochem Biophys Res Commun 2002; 293:497-500. [PMID: 12054628 DOI: 10.1016/s0006-291x(02)00232-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
High levels of homocysteine induce a sustained injury on arterial endothelial cells which accelerates the development of thrombosis and atherosclerosis. Some of the described effects of homocysteine on endothelial cells are features shared with an anti-angiogenic response. Therefore, we studied the effects of homocysteine on key steps of angiogenesis using bovine aorta endothelial cells as a model. Homocysteine decreased proliferation and induced differentiation. Furthermore, 5 mM homocysteine produced strong inhibitions of matrix metalloproteinase-2 and urokinase, two proteolytic activities that play a key role in extracellular matrix re-modeling, and decreased migration and invasion, other two key steps of angiogenesis. This study demonstrates that homocysteine can inhibit several steps of the angiogenic process.
Collapse
Affiliation(s)
- Salvador Rodríguez-Nieto
- Department of Molecular Biology and Biochemistry, Faculty of Sciences, University of Málaga, Málaga E-29071, Spain
| | | | | | | | | | | |
Collapse
|