Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.
Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, TIK 3M4, Canada.
Sci Rep. 2019 Apr 23;9(1):6448. doi: 10.1038/s41598-019-42686-w.
Well-fed prepuberal Holstein bulls had larger testes, earlier puberty, higher LH, testosterone and IGF-1, earlier and more proliferating and differentiating Sertoli cells, and greater sperm production potential. The objective was to determine effects of pre-pubertal nutrition on mRNA expression of testicular genes. Holstein bull calves were fed high or low diets (20 or 12% crude protein, respectively and 71.6 or 64.4% Total Digestible Nutrients) from 2 wk, castrated at 8, 16, 24 and 32 wk and testicular mRNA extracted and sequenced. Differential expression of genes mainly occurred at 16 and 24 wk. At 16 wk, functional analysis (DAVID) of DE mRNA revealed common biological processes including "cholesterol" and "fatty acid biosynthesis," with most genes (including HMGCR, HMGCS1, HSD17) upregulated in high-diet bulls (P < 0.05). Major pathways enriched at 16 wk were "cholesterol biosynthesis", "steroid metabolism" and "activation of gene expression by Sterol regulatory element binding protein (SREBP)" (P < 0.05). In high-diet bulls, mature Sertoli cell marker Connexin 43, was upregulated at 16 wk and immature Sertoli cell marker (AMH) downregulated at 24 wk. There was an indirect interaction between insulin family receptor and most upregulated cholesterol biosynthesis genes. Pre-pubertal nutrition enhanced testicular cholesterol/steroid biosynthesis and Sertoli cell maturation.
营养充足的青春期前荷斯坦公牛具有更大的睾丸、更早的青春期、更高的 LH、睾酮和 IGF-1、更早且更多增殖和分化的支持细胞，以及更大的精子产生潜力。目的是确定青春期前营养对睾丸基因 mRNA 表达的影响。荷斯坦公牛犊从 2 周龄开始分别饲喂高或低日粮（分别为 20%或 12%粗蛋白和 71.6%或 64.4%总可消化养分），8、16、24 和 32 周龄时去势，并提取和测序睾丸 mRNA。基因的差异表达主要发生在 16 和 24 周龄。在 16 周龄时，差异表达 mRNA 的功能分析（DAVID）揭示了共同的生物学过程，包括“胆固醇”和“脂肪酸生物合成”，大多数基因（包括 HMGCR、HMGCS1、HSD17）在高日粮公牛中上调（P<0.05）。在 16 周龄时，富集的主要途径是“胆固醇生物合成”、“类固醇代谢”和“固醇调节元件结合蛋白 (SREBP) 激活基因表达”（P<0.05）。在高日粮公牛中，成熟支持细胞标志物 Connexin 43 在 16 周龄上调，不成熟支持细胞标志物（AMH）在 24 周龄下调。胰岛素家族受体与大多数上调的胆固醇生物合成基因之间存在间接相互作用。青春期前营养增强了睾丸胆固醇/类固醇生物合成和支持细胞成熟。
