Maternal Taurine Supplementation Enhances Thermogenesis of Newborn Lambs by Promoting Brown Adipogenesis

This study aimed to investigate the effect of maternal taurine (Tau) supplementation during gestation on the development of brown adipose tissue (BAT) and the thermogenesis of offspring lambs. Sixty ewes were randomly divided into three groups and daily supplemented with 0 g (control group), 2 g (low Tau), and 4 g (high Tau) during the gestation period after artificial insemination. The body surface temperature of newborn lambs was measured daily. At 15 days of age, lambs were slaughtered for sample collection. Compared to the control group, lambs in the high-Tau group exhibited higher body temperatures (p < 0.05). Maternal Tau-treated lambs had higher expression of UCP1 (p < 0.05), a greater number of multilocular brown adipocytes, and increased mitochondrial count in the BAT (p < 0.05). Additionally, there were higher copies of mitochondrial DNA and expression of mitochondrial proteins in the maternal Tau-treated lambs (p < 0.05). Enhanced AMPK and ULK1 activation (p < 0.05) were also observed in the BAT of 15-day-old lambs. Further analysis of the effects of Tau on BAT stromal vascular fraction (SVF) cells revealed that Tau treatment upregulated UCP1 during the brown adipogenic differentiation stages (p < 0.05). Consistently, Tau treatment upregulated mitochondrial biogenesis genes and increased the number of mitochondria (p < 0.05). Tau treatment significantly upregulated PGC1a and SIRT3, as well as activated AMPK and ULK1 (p < 0.05). Mitophagy is initiated, but the mitochondrial morphology remains stable. In conclusion, maternal Tau supplementation during gestation promotes brown adipogenesis and enhances the thermogenic activity of offspring lambs by activating the AMPK-PGC1a signaling pathway.