Tryptophan regulates food intake in growing pigs by modulating hypothalamic AMPK–mTOR signalling pathway

• DOI: 10.1017/s0007114524003210
• Publication Date: 2024-12-13T13:21:53Z
• Authors: Juexin Fan; Yuezhou Yao; Leli Wang; Feiyue Chen; Zhenguo Hu; Kaihuan Xie; Shuzhong Jiang; Xiongzhuo Tang
• Keywords: Orexigenic; Anorectic; Peptide YY

Tryptophan (Trp) is an essential amino acid acting as a key nutrition factor regulating animal growth and development. But how Trp modulates food intake in pigs still not well known. Here, we investigated the effect of dietary supplementation with different levels on growing pigs. The data showed that standardized ileal digestibility (SID) to Lysine (Lys) ratio at both 0.18 0.20 significantly increased by activating expression orexigenic gene agouti-related peptide (AgRP) inhibiting anorexigenic pro-opiomelanocortin (POMC), cocaine- amphetamine-regulated transcript (CART) melanocortin receptor 4 (MC4R) hypothalamus. Meanwhile, level hormones appetite-regulating YY (PYY) duodenum serum, Leptin were also decreased. Importantly, kynurenine serotonin metabolic pathways activated upon downregulate MC4R Further mechanistic studies revealed reduced hypothalamic AMP-activated protein kinase (AMPK) pathway, which turn inhibited mTOR /S6K1 activity stimulate intake. Together, our study unravels expands its potential application developing intervention strategy pig production.