Garlic essential oil supplementation modulates colonic microbiota compositions and regulates immune response in weaned piglets.

The objective of this study was to investigate the colonic microbiome compositions and immune response and reveal their correlations in weaned piglets fed with garlic essential oil (GEO). Twelve 21-day-old crossbred piglets with the same parity and similar weight (BW = 7.07 ± 0.37 Kg) were randomly divided into control and experimental groups based on BW and sex, which fed either a basal diet (CON group), or a basal diet supplemented with 1.5 g/kg GEO (GEO group). UHPLC-QE-MS showed the main component of GEO were belonged to carbohydrates, organic acid, flavonoids, phenylpropanoids and terpenoids. GEO decreased serum IL-1ß, IL-8 content and the down-regulated mRNA expression of IFN-γ, TLR2 in jejunal mucosa but increased serum IgG, IL-4 content and up-regulated the mRNA expression of IL-4, IL-1ß, TNF-α in ileal mucosa. What's more, the metagenomic analysis demonstrated that GEO increased the abundance of Bacteroidetes, Euryarchaeota and Spirochaetes, while decreased the abundance of Firmicutes and Actinobacteria at Phylum level and Selenomonas_boris, Selenomonadaceae_bacterium_DSM_108025, Clostridiales_bacterium and Phascolarctobacterium_succinatutens at species level. Notably, the main function pathway of virulence factor (VFDB) enriched in GEO group were Fibronection-binding protein, Zn++ metallophrotease and Capsular polysaccharide, while the main function pathway of VFDB enriched in CON group were heme biosynthesis, Lap and FeoAB. Spearman correlation analysis indicated the Spirochaetes had a positive association with IL-6 and IL-4. Acinobacteria was positively correlated with IL-1ß, while negative with the IL-6; In addition, Euryarchaeota had a positive correlation with IL-4, but a negative correlation with IL-1ß; Tenericutes was negative with IL-8; Phascolarcolarctobacterium_succinatutens and was negative with IL-6; Ruminococcaceae_bacterium was negative with TNF-α. While Selenomonadaceae_bacterium_DSM_108025 had a positive correlation with IL-8. In conclusion, our results uncovered that immune regulation effects of GEO may be associated with the microbiome compositions in response to GEO.

Delphinidin-induced autophagy protects pancreatic ß cells against apoptosis resulting from high-glucose stress via AMPK signaling pathway.

Hyperglycemia, a diagnostic characteristic of diabetes mellitus, is detrimental to pancreatic ß cells. Delphinidin, a member of the anthocyanin family, inhibits glucose absorption, increases glucagon-like peptide-1 (GLP-1) secretion, and improves insulin secretion in diabetes. However, whether delphinidin plays a protective role in pancreatic ß-cell mass and function is not clear. In this study, delphinidin was found to decrease the high-glucose-induced apoptosis of RIN-m5F pancreatic ß cells. In addition, delphinidin induced autophagy in RIN-m5F cells under the normal and high-glucose conditions, while 3-methyladenine (3-MA) inhibition of autophagy significantly diminished the protective role of delphinidin against high-glucose-induced apoptosis of pancreatic ß cells. Delphinidin also decreased the level of cleaved caspase 3 and increased the phosphorylation level of AMP-activated protein kinase α (AMPKα) Thr172. Compound C, an AMPK inhibitor, was found to decrease the ratio of LC3-II/LC3-I, and the apoptotic rate of high-glucose-injured cells was increased after treatment with delphinidin, indicating that delphinidin attenuated the negative effects of high-glucose stress to cells. In conclusion, our data demonstrate that delphinidin protects pancreatic ß cells against high-glucose-induced injury by autophagy regulation via the AMPK signaling pathway. These findings might shed light on the underlying mechanisms of diabetes and help improve the prevention and therapy of this common disease.