Taurine and betaine promote lactate clearance in canine hepatocytes by enhancing gluconeogenesis

While lactate accumulation in muscles contributes to fatigue, its efficient clearance-primarily via hepatic gluconeogenesis (Cori cycle)-is vital for recovery and sustained performance. This study investigates whether taurine and betaine can enhance this hepatic lactate clearance capacity by modulating gluconeogenesis in canine hepatocytes. The results showed that taurine and betaine significantly promoted lactate clearance in canine hepatocytes. In addition, taurine and betaine significantly increased the levels of phosphoenolpyruvate and glucose in hepatocytes. Meanwhile, taurine and betaine increased the mRNA and protein expression levels of gluconeogenesis-related gene, including pyruvate carboxylase (PC), phosphoenolpyruvate carboxykinase (PEPCK), fructose-1,6-bisphosphatase (FBP1) and glucose-6-phosphatase (G6PC). Consistently, the enhanced activities of PEPCK and G6PC provide functional evidence that taurine and betaine boost the gluconeogenic flux in hepatocytes. Taken together, this study reveals the potential regulatory effects of taurine and betaine on lactate metabolism and gluconeogenesis in canine hepatocytes, providing new insights for recovery strategies in canines after exercise.