Mitochondrial mechanism of oxidative stress and systemic hypertension in hyperhomocysteinemia

Tyagi, Neetu; Moshal, Karni S.; Ovechkin, Alexander V.; Rodríguez, Walter; Steed, Mesia; Henderson, Brooke C.; Roberts, Andrew M.; Joshua, Irving G.; Tyagi, Suresh C.

doi:10.1002/jcb.20578

Cited by 49 publications

(42 citation statements)

References 57 publications

(54 reference statements)

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“…Our study corelated the mitochondrial translocation of calpain-1 with the induction of intramitochondrial oxidative burst with Hcy. The mitochondrial oxidative burst is caused by imbalance between the enzymes that catalyze redox reaction such as mitochondrial membrane respiratory enzymes (NOX) and its antioxidant counterpart, which consists of TRX (32). In this study, we employed different approaches to determine the redox status of mitochondrial in response to Hcy and confirmed that Hcy-induced ROS production was of mitochondrial origin and is calpain mediated.…”

Section: Discussionmentioning

confidence: 85%

Homocysteine-mediated activation and mitochondrial translocation of calpain regulates MMP-9 in MVEC

Moshal¹,

Singh²,

Sen³

et al. 2006

American Journal of Physiology-Heart and Circulatory Physiology

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. Homocysteine-mediated activation and mitochondrial translocation of calpain regulates MMP-9 in MVEC. Am J Physiol Heart Circ Physiol 291: H2825-H2835, 2006. First published July 28, 2006 doi:10.1152/ajpheart.00377.2006 is associated with atherosclerosis, stroke, and dementia. Hcy causes extracellular matrix remodeling by the activation of matrix metalloproteinase-9 (MMP-9), in part, by inducing redox signaling and modulating the intracellular calcium dynamics. Calpains are the calcium-dependent cysteine proteases that are implicated in mitochondrial damage via oxidative burst. Mitochondrial abnormalities have been identified in HHcy. The mechanism of Hcy-induced extracellular matrix remodeling by MMP-9 activation via mitochondrial pathway is largely unknown. We report a novel role of calpains in mitochondrial-mediated MMP-9 activation by Hcy in cultured rat heart microvascular endothelial cells. Our observations suggested that calpain regulates Hcy-induced MMP-9 expression and activity. We showed that Hcy activates calpain-1, but not calpain-2, in a calcium-dependent manner. Interestingly, the enhanced calpain activity was not mirrored by the decreased levels of its endogenous inhibitor calpastatin. We presented evidence that Hcy induces the translocation of active calpain from cytosol to mitochondria, leading to MMP-9 activation, in part, by causing intramitochondrial oxidative burst. Furthermore, studies with pharmacological inhibitors of calpain (calpeptin and calpain-1 inhibitor), ERK (PD-98059) and the mitochondrial uncoupler FCCP suggested that calpain and ERK-1/2 are the major events within the Hcy/MMP-9 signal axis and that intramitochondrial oxidative stress regulates MMP-9 via ERK-1/2 signal cascade. Taken together, these findings determine the novel role of mitochondrial translocation of calpain-1 in MMP-9 activation during HHcy, in part, by increasing mitochondrial oxidative tress. cysteine proteases; thioredoxin; Nicotinamide adenine dinucleotide phosphate-oxidase-4; mitochondrial redox signaling; cardiovascular remodeling; calcium; extracellular regulated kinase 1/2; mitogenactivating protein kinase; calpastatin; antiproteolytic therapy; microvascular endothelial cells; matrix metalloproteinase-9 A GROWING BODY OF LITERATURE indicates that elevated levels of homocysteine [hyperhomocysteinemia (HHcy)] are an independent risk factor for coronary, cerebrovascular, and peripheral atherosclerotic diseases (5, 11, 12). Matrix metalloproteinases (MMPs) are the members of Zn-containing endopeptidases that share structural domains but differ in the substrate specificity, cellular sources, and induciblity that are responsible for matrix turnover. It is well known that Hcy-induced vascular dysfunction is caused by extracellular matrix remodeling. Hcy induces extracellular matrix remodeling by MMP-9 activation, in part, by inducing the redox signaling and modulating the intracellular calcium homeostasis (13,14,19,20).Calpains are the family of calcium-dependent cysteine proteases that have previously been i...

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Section: Discussionmentioning

confidence: 85%

Homocysteine-mediated activation and mitochondrial translocation of calpain regulates MMP-9 in MVEC

Moshal¹,

Singh²,

Sen³

et al. 2006

American Journal of Physiology-Heart and Circulatory Physiology

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“…reduction of vessel radius by thickening the arterial wall 5) . Previous observational studies reported a positive association between the plasma concentration of total homocysteine (tHcy) and vascular events [6][7][8] .…”

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confidence: 99%

Homocysteine and Internal Carotid Artery Occlusion in Ischemic Stroke

Jeong

Seo

Cho

2010

JAT

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“…The results show that arterial hypertension in HHcy mice is, in part, associated with arterial remodeling and E-M uncoupling in response to MMP activation. cardiovascular dysfunction; aorta; echocardiography; extracellular matrix remodeling; in situ matrix metalloproteinase activity; cystathionine ␤-synthase; connexin; DQ gelatin; telemetry EXPERIMENTAL AND CLINICAL studies have shown that chronic elevation of homocysteine (Hcy) levels, known as hyperhomocysteinemia (HHcy), is a significant independent risk factor for cardiovascular disease (31), particularly in the development of arterial hypertension and atherosclerosis (3,24,26). The mechanisms by which HHcy affects arterial wall and induces arterial hypertension have remained unclear.…”

mentioning

confidence: 99%

“…EXPERIMENTAL AND CLINICAL studies have shown that chronic elevation of homocysteine (Hcy) levels, known as hyperhomocysteinemia (HHcy), is a significant independent risk factor for cardiovascular disease (31), particularly in the development of arterial hypertension and atherosclerosis (3,24,26). The mechanisms by which HHcy affects arterial wall and induces arterial hypertension have remained unclear.…”

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confidence: 99%

3-Deazaadenosine mitigates arterial remodeling and hypertension in hyperhomocysteinemic mice

Ovechkin¹,

Tyagi²,

Sen³

et al. 2006

American Journal of Physiology-Lung Cellular and Molecular Phys

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Chronic hyperhomocysteinemia (HHcy) is an important factor in development of arterial hypertension. HHcy is associated with activation of matrix metalloproteinases (MMPs); however, it is unclear whether HHcy-dependent extracellular matrix (ECM) accumulation plays a role in arterial hypertrophy and hypertension. We tested the hypothesis that in HHcy the mechanism of arterial hypertension involves arterial dysfunction in response to ECM accumulation between endothelial and arterial smooth muscle cells and subsequent endothelium-myocyte (E-M) uncoupling. To decrease plasma Hcy, dietary supplementation with 3-deazaadenosine (DZA), the S-adenosylhomocysteine hydrolase inhibitor, was administered to cystathionine ␤-synthase (CBS) knockout (KO) mice. Mice were grouped as follows: wild type (WT; control), WTϩDZA, CBSKO, and CBSKOϩDZA (n ϭ 4/group). Mean aortic blood pressure and heart rate were monitored in real time with a telemetric system before, during, and after DZA treatment (6 wk total). In vivo aorta function and morphology were analyzed by M-mode and Doppler echocardiography in anesthetized mice. Aorta MMP activity in unfixed cryostat sections was measured with DQ gelatin. Aorta MMP-2, MMP-9, and connexin 43 expression were measured by RT-PCR and Western blot analyses, respectively. HHcy caused increased aortic blood pressure and resistance, tachycardia, and increased wall thickness and ECM accumulation in aortic wall vs. control groups. There was a linear correlation between aortic wall thickness and plasma Hcy levels. MMP-2, MMP-9, and connexin 43 expression were increased in HHcy. In the CBSKOϩDZA group, aortic blood pressure and levels of MMP and connexin 43 were close to those found in control groups. However, removal of DZA reversed the aortic lumen-to-wall thickness ratio in CBSKO mice, suggesting, in part, a role of vascular remodeling in the increase in blood pressure in HHcy. The results show that arterial hypertension in HHcy mice is, in part, associated with arterial remodeling and E-M uncoupling in response to MMP activation. cardiovascular dysfunction; aorta; echocardiography; extracellular matrix remodeling; in situ matrix metalloproteinase activity; cystathionine ␤-synthase; connexin; DQ gelatin; telemetry EXPERIMENTAL AND CLINICAL studies have shown that chronic elevation of homocysteine (Hcy) levels, known as hyperhomocysteinemia (HHcy), is a significant independent risk factor for cardiovascular disease (31), particularly in the development of arterial hypertension and atherosclerosis (3,24,26). The mechanisms by which HHcy affects arterial wall and induces arterial hypertension have remained unclear. It has been shown that HHcy leads to arterial damage (4) and increased arterial wall stiffness (2,22).Hcy is a product of methionine metabolism that under normal conditions is converted to cystathionine by cystathionine ␤-synthase (CBS). It has been established that mice carrying a disrupted CBS gene are adequate models for HHcy. Systemic vascular cells lacking CBS (7,8) are the prime target for...

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Mitochondrial mechanism of oxidative stress and systemic hypertension in hyperhomocysteinemia

Cited by 49 publications

References 57 publications

Homocysteine-mediated activation and mitochondrial translocation of calpain regulates MMP-9 in MVEC

Homocysteine-mediated activation and mitochondrial translocation of calpain regulates MMP-9 in MVEC

Homocysteine and Internal Carotid Artery Occlusion in Ischemic Stroke

3-Deazaadenosine mitigates arterial remodeling and hypertension in hyperhomocysteinemic mice

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