Cystathionine-beta-synthase (CBS) catalyzes the rate-limiting step in the transsulfuration pathway for the metabolism of
homocysteine (Hcy) in the kidney. Our recent study demonstrates that
ischemia-reperfusion reduces the activity of CBS leading to Hcy accumulation in the kidney, which in turn contributes to renal injury. CBS is also capable of catalyzing the reaction of
cysteine with Hcy to produce
hydrogen sulfide (H(2)S), a gaseous molecule that plays an important role in many physiological and
pathological processes. The aim of the present study was to examine the effect of
ischemia-reperfusion on CBS-mediated H(2)S production in the kidney and to determine whether changes in the endogenous H(2)S generation had any impact on renal
ischemia-reperfusion injury. The left kidney of Sprague-Dawley rat was subjected to 45-min
ischemia followed by 6-h reperfusion. The
ischemia-reperfusion caused lipid peroxidation and cell death in the kidney. The CBS-mediated H(2)S production was decreased, leading to a significant reduction in the renal H(2)S level. The activity of
cystathionine-gamma-lyase, another
enzyme responsible for endogenous H(2)S generation, was not significantly altered in the kidney upon
ischemia-reperfusion. Partial restoration of CBS activity by
intraperitoneal injection of the
nitric oxide scavenger,
2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide not only increased renal H(2)S levels but also alleviated
ischemia-reperfusion-induced lipid peroxidation and reduced cell damage in the kidney tissue. Furthermore, administration of an exogenous H(2)S donor,
NaHS (100 microg/kg), improved renal function. Taken together, these results suggest that maintenance of tissue H(2)S level may offer a renal protective effect against
ischemia-reperfusion injury.