Yehui Duan1, Lingyu Zhang, Fengna Li, Qiuping Guo, Cimin Long, Yulong Yin, Xiangfeng Kong, Mijun Peng, Wence Wang. 1. Hunan Provincial Key Laboratory of Animal Nutritional Physiology and Metabolic Process; Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences; Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production; Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China. lifengna@isa.ac.cn.
Abstract
BACKGROUND: The effects and roles of the leucine (Leu) metabolite β-hydroxy-β-methylbutyrate (HMB) in lipid metabolism in adipose tissues of pigs are still unknown. OBJECTIVES: This study was conducted to investigate the effects of excess Leu versus HMB on growth, carcass traits, and lipid metabolism in adipose tissues of growing pigs. METHODS AND RESULTS: Compared to control, the Leu/HMB group significantly increased/reduced weight of total fat mass, respectively, with a concurrent increase of serum adiponectin concentration (P < 0.05). Moreover, dietary HMB supplementation regulated the expression of genes involved in adipose tissue function, accompanied by increases/decreases in the phosphorylation of AMPKα/mTOR in perirenal adipose tissue, respectively (P < 0.05). Serum IL-15 concentration and the mRNA abundance of IL-15, PGC-1α, and NRF-1 were also increased in the HMB group (P < 0.05). CONCLUSIONS: HMB supplementation can regulate adipose tissue function including fatty acid oxidation, lipolysis, and adipokine secretion. These effects may be partly mediated by AMPKα-mTOR pathway and associated with mitochondrial biogenesis, the AMPK-PGC-1α axis, and myokines secreted by muscle tissues.
BACKGROUND: The effects and roles of the leucine (Leu) metabolite β-hydroxy-β-methylbutyrate (HMB) in lipid metabolism in adipose tissues of pigs are still unknown. OBJECTIVES: This study was conducted to investigate the effects of excess Leu versus HMB on growth, carcass traits, and lipid metabolism in adipose tissues of growing pigs. METHODS AND RESULTS: Compared to control, the Leu/HMB group significantly increased/reduced weight of total fat mass, respectively, with a concurrent increase of serum adiponectin concentration (P < 0.05). Moreover, dietary HMB supplementation regulated the expression of genes involved in adipose tissue function, accompanied by increases/decreases in the phosphorylation of AMPKα/mTOR in perirenal adipose tissue, respectively (P < 0.05). Serum IL-15 concentration and the mRNA abundance of IL-15, PGC-1α, and NRF-1 were also increased in the HMB group (P < 0.05). CONCLUSIONS:HMB supplementation can regulate adipose tissue function including fatty acid oxidation, lipolysis, and adipokine secretion. These effects may be partly mediated by AMPKα-mTOR pathway and associated with mitochondrial biogenesis, the AMPK-PGC-1α axis, and myokines secreted by muscle tissues.