CBS and hyperhomocysteinemia: Remarkably, in a mouse model of hyperhomocysteinemia with a heterozygous depletion of the CBS gene (CBS (+/−) mice) it has been demonstrated that CBS (+/−) mice as expected show a lower expression of CBS but also of CSE and this was accompanied by reduced levels of H2S. Importantly, administration of the H2S donor NaSH with the drinking water in CBS (+/−) mice reduced hyperhomocysteinemia and glomerulosclerosis and normalized collagen deposition in renal cortical tissue [55,56].