Homocysteine to hydrogen sulfide: in vitro, ex vivo and in vivo

37th Congress of IUPS (Birmingham, UK) (2013) Proc 37th IUPS, SA91

Research Symposium: Homocysteine to hydrogen sulfide: in vitro, ex vivo and in vivo

S. C. Tyagi1

1. University of Louisville, Louisville, Kentucky, United States.

View other abstracts by:


Hydrogen sulfide (H(2)S) is identified as a regulator of various physiological events, including the hypertension, H(2)S is produced as a metabolite of homocysteine (Hcy) by cystathionine β-synthase (CBS), cystathionine γ-lyase (CSE), and 3-mercaptopyruvate sulfurtransferase (3MST). Although Hcy is recognized as vascular risk factor at an elevated level [hyperhomocysteinemia (HHcy)] and contributes to vascular injury leading to hypertension, the exact mechanism was unclear. To determine whether conversion of Hcy to H(2)S mitigates hypertension. Ex vivo renal artery culture with CBS, CSE, and 3MST triple gene therapy generated more H(2)S in the presence of Hcy, and these arteries were more responsive to endothelial-dependent vasodilation compared with nontransfected arteries treated with high Hcy. Cross section of triple gene-delivered renal arteries immunostaining suggested increased expression of CD31 and VEGF and diminished expression of the antiangiogenic factor endostatin. In vitro endothelial cell culture demonstrated increased mitophagy during high levels of Hcy and was mitigated by triple gene delivery. Upregulated matrix metalloproteinases-13 and downregulated tissue inhibitor of metalloproteinase-1 in HHcy were normalized by overexpression of triple genes. Together, these results suggest that H(2)S plays a key role in hypertension during HHcy.



Where applicable, experiments conform with Society ethical requirements.

Site search

Filter

Content Type