The Effect of Dietary Modulation of Sulfur Amino Acids on Cystathionine Beta Synthase–Deficient Mice

The document discusses a series of long-term dietary studies conducted on a mouse model (Tg-I278T Cbs –/–) with cystathionine β synthase (CBS) deficiency to evaluate the effectiveness of nutritional treatment strategies for this condition. CBS deficiency in humans leads to elevated plasma total homocysteine (tHcy) and methionine levels, along with decreased plasma cysteine, and is treated with vitamin therapy and dietary manipulation. The Tg-I278T Cbs –/– mice used in the study have no detectable CBS activity, extremely high plasma tHcy, slightly elevated plasma methionine, low plasma cysteine, and exhibit symptoms such as osteoporosis, loss of fat mass, reduced lifespan, and facial alopecia. The diets tested varied in sulfur amino acids or their precursors. The findings from these studies are discussed in terms of their implications for CBS deficiency and the interaction between genes and diet.