Rotavirus (RV) is a significant contributor to diarrhea in both young children and animals, especially in piglets, resulting in considerable economic impacts on the global pig industry. Isoleucine (Ile), a branched-chain amino acid, is crucial for regulating nutrient metabolism and has been found to help mitigate diarrhea. This study aimed to assess the impact of isoleucine supplementation in feed on colonic barrier function, colonic microbiota, and metabolism in RV-infected weanling piglets. A total of thirty-two weaned piglets, aged 21 days, were randomly assigned to two dietary groups (each further divided into two subgroups, with eight replicates in each subgroup), receiving diets with either 0% or 1% isoleucine for a duration of 14 days. One group from each treatment was then challenged with RV, and the experimental period lasted for 19 days. The results showed that dietary Ile significantly increased the secretion of IL-4, IL-10, and sIgA in the colon of RV-infected weanling piglets (p < 0.05). In addition, Ile supplementation notably increased the expression of tight junction proteins, including Claudin-3, Occludin, and ZO-1 (p < 0.01), as well as the mucin protein MUC-1 in the colon of RV-infected weanling piglets (p < 0.05). Gut microbiota analysis revealed that dietary Ile increased the relative abundance of Prevotella and decreased the relative abundance of Rikenellaceae in the colons of RV-infected weanling piglets. Compared with the RV+CON, metabolic pathways in the RV+ILE group were significantly enriched in vitamin digestion and absorption, steroid biosynthesis, purine metabolism, pantothenate and CoA biosynthesis, cutin, suberine, and wax biosynthesis, as well as fatty acid biosynthesis, and unsaturated fatty acid biosynthesis. In conclusion, dietary Ile supplementation can improve immunity, colonic barrier function, colonic microbiota, and colonic metabolism of RV-infected weaned piglets. These findings provide valuable insights into the role of isoleucine in the prevention and control of RV.

为探究不同日龄皖西白鹅血液指标、免疫器官组织形态和抗氧化指标的变化,本实验随机选择 30 日龄健康皖西白鹅饲养,分别在 60、90 日龄和 105 日龄翅下静脉采血,60、90 日龄时处死并取胸腺、脾脏、法氏囊和肝脏用于指标测定.结果显示:在血常规指标中,白细胞数、红细胞数随日龄增加而升高,其中 90日龄皖西白鹅的红细胞分布宽度标准差指标较 60、105 日龄显著升高.与 60 日龄相比,90、105 日龄皖西白鹅的血液生化指标水平显著升高.无机磷、间接胆红素、谷丙转氨酶、碱性磷酸酶、天门冬氨酸基转移酶、血清乳酸脱氢酶、总蛋白、甘油三酯水平随日龄增加而降低,钙和球蛋白水平则随日龄增加而显著升高.与60 日龄皖西白鹅相比,90 日龄皖西白鹅法氏囊小结平均个数、法氏囊小结平均面积显著下降,脾脏重量显著增加,脾小结平均面积显著降低.抗氧化指标中,60 日龄皖西白鹅法氏囊GSH显著高于 90 日龄.在 60～105日龄阶段,通过血液生理生化指标变化情况说明 90 日龄皖西白鹅生长发育已趋于成熟;90 日龄时中枢免疫器官胸腺仍继续发育,而法氏囊结构上呈现退化趋势,外周免疫器官脾脏从 60 日龄至 90 日龄持续发育,60日龄时肝脏在结构上成熟.综上,90 日龄时皖西白鹅免疫器官发育基本成熟,血液生理生化水平趋于稳定.

本实验旨在探究不同生长阶段皖西白鹅的盲肠组织形态及微生物菌群多样性.选取 180 只 30 日龄皖西白鹅,饲喂玉米-豆粕型基础日粮,实验期 60 d,分别在 60 日龄和 90 日龄采集鹅盲肠肠段和盲肠内容物,进行HE染色分析盲肠组织形态,利用 16S rDNA测序技术研究盲肠内容物微生物多样性差异.结果显示:随着年龄增长,90日龄盲肠肌层厚度高于60日龄(P<0.05),绒毛高度/隐窝深度比值低于60日龄(P<0.01);90日龄Shanoon指数显著高于60日龄;门水平核心菌群在60日龄和90日龄中均为拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)和变形菌门(Proteobacteria);属水平核心菌群在 60 d和 90 d中最高的 3 个属依次为拟杆菌属(Bacteroides)、未知明瘤胃菌属(Unspecified_Ruminococcaceae)和颤螺旋菌属(Oscillospira);60 日龄盲肠富集 3 个门的微生物菌群,为厚壁菌门(Firmicutes)、放线菌门(Actinomycetales)和变形菌门(Proteobacteria),90日龄盲肠富集4个门的微生物菌群,为厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)、梭杆菌门(Usobacteria)和疣微菌门(Verrucomicrobia);60 日龄和 90 日龄均显著富集缬氨酸、亮氨酸和异亮氨酸生物合成(Valine,Leucine And Isoleucine Biosynthesis)等 9 个代谢活动的信号通路.结果表明,随着日龄增长,皖西白鹅在养分利用能力和免疫屏障功能上逐渐增强,其盲肠优势菌群的物种丰度不断增加和多样性趋于稳定,在一定程度上刺激并促进盲肠组织结构在健康状态下的动态变化.

This study aimed to investigate the effect of boron on porcine mammary epithelial cells (PMECs) survival, cell cycle, and milk fat synthesis. PMECs from boron-treated groups were exposed to 0–80 mmol/L boric acid concentrations. Cell counting kit-8 and flow cytometry assays were performed to assess cell survival and the cell cycle, respectively. Triacylglycerol (TAG) levels in PMECs and culture medium were determined by a triacylglycerol kit while PMECs lipid droplet aggregation was investigated via oil red staining. Milk fat synthesis–associated mRNA levels were determined by quantitative real-time polymerase chain reaction (qPCR) while its protein expressions were determined by Western blot. Low (0.2, 0.3, 0.4 mmol/L) and high (> 10 mmol/L) boron concentrations significantly promoted and inhibited cell viabilities, respectively. Boron (0.3 mmol/L) markedly elevated the abundance of G2/M phase cells. Ten mmol/L boron significantly increased the abundances of G0/G1 and S phase cells, but markedly suppressed G2/M phase cell abundance. At 0.3 mmol/L, boron significantly enhanced ERK phosphorylation while at 0.4, 0.8, 1, and 10 mmol/L, it markedly decreased lipid droplet diameters. Boron (10 mmol/L) significantly suppressed ACACA and SREBP1 protein expressions. The FASN protein levels were markedly suppressed by 0.4, 0.8, 1, and 10 mmol/L boron. Both 1 and 10 mmol/L markedly decreased FASN and SREBP1 mRNA expressions. Ten mmol/L boron significantly decreased PPARα mRNA levels. Low concentrations of boron promoted cell viability, while high concentrations inhibited PMECS viabilities and reduced lipid droplet diameters, which shows the implications of boron in pregnancy and lactation.

Intramuscular fat (IMF) is a key index to measure the tenderness and flavor of pork. Wannanhua pig, a famous indigenous pig breed in Anhui Province, is renowned for its high lipid deposition and high genetic divergence, making it an ideal model for investigating the lipid position trait mechanisms in pigs. However, the regulatory mechanisms of lipid deposition and development in pigs remain unclear. Furthermore, the temporal differences in gene regulation are based on muscle growth and IMF deposition. The purpose of this study was to study the expression changes of longissimus dorsi (LD) at different growth stages of WH pigs at the molecular level, to screen the candidate genes and signaling pathways related to IMF during development by transcriptome sequencing technology, and to explore the transcriptional regulation mechanism of IMF deposition-related genes at different development stages. In total, 616, 485, and 1487 genes were differentially expressed between LD60 and LD120, LD120 and LD240, and LD60 and LD240, respectively. Numerous differentially expressed genes (DEGs) associated with lipid metabolism and muscle development were identified, and most of them were involved in IMF deposition and were significantly up-regulated in LD120 and LD240 compared to LD60. STEM (Short Time-series Expression Miner) analysis indicated significant variations in the mRNA expression across distinct muscle development stages. The differential expression of 12 selected DEGs was confirmed by RT-qPCR. The results of this study contribute to our understanding of the molecular mechanism of IMF deposition and provide a new way to accelerate the genetic improvement of pork quality.

本试验旨在研究苏氨酸和异亮氨酸对皖西白鹅生长性能、盲肠组织形态、细胞因子和微生物区系的影响.选取30日龄皖西白鹅180只,随机分为3组,每组3个重复,每个重复20只.对照组饲喂基础饲粮,苏氨酸组在基础饲粮中添加2.0 g/kg的苏氨酸,异亮氨酸组在基础饲粮中添加2.5 g/kg的异亮氨酸.试验期60 d.结果表明:1)苏氨酸组和异亮氨酸组61～90日龄料重比(F/G)极显著低于对照组(P<0.01).2)60日龄时,异亮氨酸组盲肠绒毛高度和隐窝深度显著或极显著高于对照组(P<0.05或P<0.01).90日龄时,苏氨酸组盲肠隐窝深度显著高于对照组(P>0.05),苏氨酸组和异亮氨酸组盲肠绒毛高度/隐窝深度显著低于对照组(P<0.05).3)90日龄时,苏氨酸组和异亮氨酸组盲肠肿瘤坏死因子-α(TNF-α)含量显著低于对照组(P<0.05),苏氨酸组盲肠干扰素-γ(IFN-γ)和白细胞介素-4(IL-4)含量显著高于对照组(P<0.05).4)90日龄时,异亮氨酸组盲肠软壁菌门(Tenericutes)相对丰度极显著高于对照组(P<0.01),苏氨酸组盲肠颤螺旋菌属(Oscillospira)、消化球菌属(Peptococcus)和S24_7科未分类菌属(unspecified_S24_7)相对丰度显著高于对照组(P<0.05).由此可见,饲粮中添加2.0 g/kg苏氨酸或2.5 g/kg异亮氨酸均可一定程度提高皖西白鹅生长性能,异亮氨酸对60日龄盲肠组织结构的影响较大,苏氨酸对90日龄盲肠组织结构的影响较大.饲粮中添加2.5 g/kg异亮氨酸增加了皖西白鹅盲肠软壁菌门相对丰度,饲粮中添加2.0 g/kg苏氨酸增加了皖西白鹅盲肠颤螺旋菌属、消化球菌属和S24_7科未分类菌属相对丰度.

The intestinal surface faces the challenging task of protecting a vast surface area while maintaining homeostasis with abundant commensal microorganisms and preventing pathogen invasion. The mucosal epithelial cells of the intestine and its cell tight junctions constitute the mechanical barrier. which significantly maintains the integrity and function of the intestine. For humans and animals. small intestinal digestion and absorption capacity for nutrients are often severely impaired, which confirms that maintaining the morphological integrity of the intestinal villi is very important. As an essential amino acid in animals, isoleucine can improve intestinal absorption and barrier function, as well as participates in protein synthesis and serves as an energy source for intestinal epithelial cells. In the current study, we attempted to determine further the function of isoleucine and explored the possible mechanism of isoleucine on the structure and function of intestinal mucosa through in vivo and in vitro experiments. For in vivo experiments, a total of 80 SD rats were selected and randomly divided into 4 groups. Different concentrations of isoleucine (0, 0.5, 2.5. and 5 mg/mL) were added to the drinking water of these groups of mice, and the experimental period was settled for 28 d. Further, the morphological structure and the expression level of tight junction protein in the rat intestine were measured. For in vitro study, rat jejunal epithelial cell line IEC-6 was treated with different concentrations of isoleucine (0, 0.1. 0.5, 2.5. 12.5, and 25.0 mmol/L). Cell viability was measured by MTT, while cell cycle and apoptosis were measured by flow cytometry, and tight junction protein expression in cells was analyzed by Western blot. The results revealed that 2.5 mg/kg isoleucine supplemented in rat drinking water significantly increased the ratio of villus height to villus crypt depth: for example, improved villus height and reduced crypt depth of duodenum, jejunum, and ileum (P<0.05) were observed. Moreover, 2.5 mg/kg isoleucine treatment also increased the expression of jejunal tight junction proteins (Claudin-1 and Occludin) in the rat small intestine (P<0.05). Further, the in vitro experiments results revealed that the lower concentration of isoleucine (0.5 mmol/L) improved the IEC-6 cell viability (P<0.05). whereas the higher concentration (25 mmol/L) decreased the cell viability (P<0.05). Overall, the cell flow cytometry results indicated that the appropriate concentration of isoleucine significantly promoted the IEC-6 cell proliferation, decreased cell apoptosis, and increased the expression of tight junction protein (Claudin-1 and Occludin), whereas the high concentration of isoleucine exhibited an inhibitory effect. In conclusion, isoleucine can improve the morphology structure of the small intestine, especially promote the villi height and increase the absorption surface area. The underlying mechanism of isoleucine regulation is that it can promote the proliferation and reduce the apoptosis of small intestinal epithelial cells, thereby increasing the villi height: in addition. isoleucine also improves the synthesis of tight junction proteins in epithelial cells. thereby promoting the mucosal barrier function of the rat jejunum. This current research elucidates new insights into the application of isoleucine in human and animal intestinal health and provides a direction for further research on the function of amino acids.