Neonatal vitamin A but not retinoic acid administration increases intramuscular adipocyte number in sheep by promoting vascularization  

作　　者：Zhongzuo Huang Xiaoxiao Yu Zongyou Jiang Gaojian Tang Shaoqi Gao Yifan Xiang Yicheng Luo Boping Ye Yating Li Pengkang Song Yu Xin Min Du Junxing Zhao Bo Wang 

机构地区：[1]State Key Laboratory of Animal Nutrition and Feeding,College of Animal Science and Technology,China Agricultural University,Beijing 100193,China [2]College of Animal Science,Shanxi Agricultural University,Taigu 030801,China [3]Laboratory of Nutrigenomics and Growth Biology,Department of Animal Sciences,Washington State University,Pullman,WA 99164,USA

出　　处：《Animal Nutrition》2024年第4期215-225,共11页动物营养(英文版)

基　　金：supported by grants from the National Natural Science Foundation of China (32272892,31972559);the Key Research and Development Program-Key Projects (2021YFD1200900 and 2023YFD1301302);the Young Talent Supporting Program Funding of the College of Animal Science and Technology,and China Agricultural University Education Foundation Grant(1041-2221002)

摘　　要：This study investigated whether vitamin A(VA)administration during the neonatal stage could increase the number of intramuscular adipocytes in Hu sheep by promoting vascularity.A total of 56 newborn male Hu sheep were divided into four groups and received intramuscular injections of either 0,7500 IU retinoic acid(RA),7500 IU VA,or a combination of 7500 IU VA and 5 mg SU5416(an angiogenic inhibitor),at 1,7,14,and 21 days of age.At 15 days of age,6 sheep from each group were randomly selected and sacrificed for intramuscular adipogenic capacity analysis.The remaining 8 sheep in each group were raised until they were 8 months old.VA-treated sheep exhibited an increase in preadipocytes,elevated expression of adipogenic genes(CCAAT enhancer binding protein alpha[CEBPA]and CCAAT enhancer binding protein beta[CEBPB])and angiogenic genes(vascular endothelial growth factor A[VEGFA]),and stromal vascular fraction cells in the longissimus dorsi(LD)muscle with enhanced adipogenic capacity(P<0.05).These effects were entirely negated by SU5416.Upon slaughter,VA increased final weight,carcass weight,and average daily gain(P<0.05)but did not affect feed intake at 21 to 32 weeks(P=0.824).VA increased the number of intramuscular adipocytes in the LD and semitendinosus(ST)muscle(P<0.05)without changing the adipocyte number of the omentum,perirenal and subcutaneous fats(P>0.05).VA injections also increased intramuscular triglyceride(TG)content(P=0.016)without changing the omentum fat weight or subcutaneous fat thickness(P>0.05),but it did increase the perirenal fat weight(P=0.011).Consistently,SU5416 mitigated the effects of VA on intramuscular TG content and adipocyte count,correlating with a decrease in vascularity.In contrast,RA injections didn't affect the intramuscular fat(P=0.744)but reduced the TG content of the omentum and perirenal fat(P<0.05).In conclusion,intramuscular injections of VA but not RA at the neonatal stage improved the growth performance of Hu sheep,increasing the number of intramuscular adipocytes and marblin

关 键 词：SHEEP Vitamin A Retinoic acid Intramuscular fat ADIPOGENESIS Angiogenesis 

分 类 号：R73[医药卫生—肿瘤]