Hyperhomocysteinemia Induced by Methionine Excess is Effectively Suppressed by Betaine in Geese

SIMPLE SUMMARY: Methionine is a proteogenic sulfur amino acid with a vital role in intermediary metabolism. However, excess Methionine (Met) intake is toxic, leading to hyperhomocysteinemia. Betaine supplementation effectively ameliorates biochemical abnormalities. However, a lack of genetic information hinders the understanding of the mechanisms underlying methionine excess-mediated effects and whether Bet can effectively suppress these effects in geese. This study was performed to evaluate the effects of excess methionine on growth performance, serum homocysteine levels, apoptotic rates, and Bax and Bcl-2 protein levels in geese and to study the role of betaine in relieving excess Met-induced hyperhomocysteinemia. It was found that excess methionine reduces body weight induced by myocardial apoptosis, and betaine can be used to effectively lower plasma homocysteine levels. ABSTRACT: The objective of our study was to investigate the effects of excess Methionine (Met) on the growth performance, serum homocysteine levels, apoptotic rates, and Bax and Bcl-2 protein levels in geese and to study the role of Bet (betaine) in relieving excess Met-induced hyperhomocysteinemia (HHcy). In this study, 150 healthy male 14-day-old Yangzhou geese of similar body weight were randomly distributed into three groups with five replicates per treatment and 10 geese per replicate: the control group (fed a control diet), the Met toxicity group (fed the control diet +1% Met), and the Bet detoxification group (fed the control diet +1% Met +0.2% Bet). At 28, 49, and 70 d of age, the geese in the Met toxicity group had significantly lower body weights than those in the control group (p < 0.05). The serum homocysteine levels in geese at 70 d of age in the detoxification group were significantly lower than those in the Met toxicity group (p < 0.05). Compared with the control, Met significantly increased cardiomyocyte apoptosis rates, while Bet reduced them. In conclusion, our results suggest that excess methionine reduces body weight induced by myocardial apoptosis, and Bet can be used to effectively lower plasma homocysteine levels.