Identification of microRNA transcriptome reveals that miR-100 is involved in the renewal of porcine intestinal epithelial cells

MicroRNAs play important roles in various cellular processes, including differentiation, proliferation and survival. Using a pig model, this study sought to identify the miRNAs responsible for crypt-villus axis renewal of the small intestinal epithelium.Compared to the villus upper cells, there were 15 up-regulated and 41 down-regulated miRNAs in the crypt cells of the jejunum.Notably, we found that miR-100 was expressed more in the villus upper cells than in the crypt cells, suggesting an effect on intestinal epithelium differentiation. Overexpression of miR-100 increased the activity of alkaline phosphatase, confirming that miR-100 promoted IPEC-J2 cell differentiation. MiR-100 can inhibit cell proliferation as evidenced by CCK-8 and cell cycle assay results. We also showed that miR-100 significantly inhibited the migration of IPEC-J2 cells and promoted cell apoptosis through caspase-3-dependent cleavage of Bcl-2. Furthermore, FGFR3 was identified as a potential target of miR-100 by bioinformatics analysis. We confirmed that overexpression of miR-100 suppressed FGFR3 expression in IPEC-J2 cells by directly targeting the FGFR3 3′-UTR. This is the first report of miRNAs acting on the renewal of the intestinal crypt-villus axis.Our results also showed that miR-100 promotes the differentiation and apoptosis, and inhibits the proliferation and migration of enterocytes of pigs.

Early weaning leads to the remodeling of lipid profile in piglet jejunal crypt cells during post-weaning days

Reportedly,proteins involved in lipid metabolism change significantly in the jejunal crypt cells of earlyweaned piglets,but the exact lipid profile change remains uncertain.In the present study,32 piglets weaned at 21 d of age were randomly divided into 4 groups with 8 replicates.The jejunal crypt cells of a group of piglets on the post-weaning day(PWD)1,3,7,and 14 were isolated per time point.Crypt cell lipid profiles were analyzed using ultra-high-performance liquid chromatography coupled with hybrid quadrupole time-of-flight mass spectrometry.This study showed that piglets suffered the greatest weaning stress on PWD 3 in terms of the lowest relative weight of the small intestine,the highest relative weight of the spleen,and the highest levels of malondialdehyde,cholesterol,and low-density lipoprotein cholesterol.The lipid profile of jejunal crypt cells including carnitine,sulfatide,sphingomyelin,hexosylceramide,and ceramide greatly changed after weaning,especially between PWD3 and 14(P<0.05).The differential lipid species between these 2 d were mainly involved in the glycerophospholipid metabolism pathway.In addition,potential lipid biomarkers for weaning stress in crypt cells such as phosphatidylcholine(PC)(9:0/26:1),PC(17:0/18:2),carnitine(24:0),carnitine(22:0),sphingomyelin(d14:1/22:0),PC(P-18:0/18:4),phosphatidylethanolamine(P-16:0/20:4),phosphatidylinositol(15:1/24:4),and dihexosylceramide(d14:1/26:1)were identified.The changes in lipid profile might be related to the inflammation caused by early weaning.These findings might provide new therapeutical targets for intestinal dysfunctions caused by weaning stress.

A water-soluble β-glucan improves growth performance by altering gut microbiome and health in weaned pigs

Beta-glucan has been shown to have a beneficial effect on gastrointestinal health.This experiment was conducted to investigate the effects ofβ-glucan isolated from Agrobacterium sp.ZX09 on growth performance and intestinal health of weaning pigs.A total of 108 weaned pigs(21 d of age;6.05±0.36 kg)were randomly divided into 3 groups(6 pens/group;6 pigs/pen),and the groups were each treated with the following diets:1)basal diet,2)basal diet supplemented with 20 mg/kg olaquindox,3)basal diet supplemented with 200 mg/kgβ-glucan,for 21 d.Compared with the control group,pigs fed with200 mg/kgβ-glucan had greaterBW,average daily gain and duodenal villus height to crypt depth ratio(P<0.05).Olaquindox increased the duodenal or jejunal villus height of pigs compared withβ-glucan.Compared with the control group,β-glucan tended to increase the occludin mRNA expression in the jejunum(0.05<P<0.10).Beta-glucan enriched the beneficial microbiota in the ileum of pigs(P<0.05).In conclusion,β-glucan may promote growth performance by improving intestinal health and increasing beneficial microbiota of weaned pigs.The study results will provide valuable theoretical guidance for the utilization ofβ-glucan in weaned pigs.