Effects of grape seed procyanidins on antioxidant function, barrier function, microbial community, and metabolites of cecum in geese.

The gut is the first line of defense for body health and is essential to the overall health of geese. Grape seed procyanidins (GSPs) are proverbial for their antioxidant, anti-inflammatory, and microflora-regulating capabilities. This study aimed to inquire into the influences of dietary GSPs on the intestinal antioxidant function, barrier function, microflora, and metabolites of geese based on 16S rRNA sequencing and metabolomics. In total, 240 twenty-one-day-old Sichuan white geese were randomly divided into 4 groups, each of which was supplied with 1 of 4 diets: basal diet or a basal diet supplemented with 50, 100, or 150 mg/kg GSPs. Diets supplemented with GSPs at different concentrations significantly increased the total antioxidant capacity and superoxide dismutase activity in cecal mucosa (P < 0.001). Dietary supplementation with 50 or 100 mg/kg GSPs significantly increased catalase activity (P < 0.001). The serum diamine oxidase, D-lactic acid, and endotoxin concentrations were decreased by GSP supplementation in the goose diet. Dietary GSP supplementation increased microbial richness and diversity, enhanced the relative abundance of Firmicutes, and decreased that of Bacteroidetes in the cecum. Diets supplemented with 50 or 100 mg/kg GSPs enriched Eubacterium coprostanoligenes and Faecalibacterium. Dietary GSPs substantially raised the acetic and propionic acid concentrations in the cecum. The butyric acid concentration increased when the GSP dosage was 50 or 100 mg/kg. Additionally, dietary GSPs increased the levels of metabolites that belong to lipids and lipid-like molecules or organic acids and derivatives. Dietary GSP supplementation at 100 or 150 mg/kg reduced the levels of spermine (a source of cytotoxic metabolites) and N-acetylputrescine, which promotes in-vivo inflammation. In conclusion, dietary supplementation with GSPs was beneficial to gut health in geese. Dietary GSPs improved antioxidant activity; protected intestinal barrier integrity; increased the abundance and diversity of cecal microflora; promoted the proliferation of some beneficial bacteria; increased the production of acetic, propionic, and butyric acids in the cecum; and downregulated metabolites associated with cytotoxicity and inflammation. These results offer a strategy for promoting intestinal health in farmed geese.

Glutathione metabolism is conserved in response to excessive copper exposure between mice liver and Aurelia coerulea polyps.

BACKGROUND: Copper (Cu) is a trace element that is engaged in various routine physiological processes. Excessive copper exposure can cause damage to organisms; however, it is unknown if the mechanisms underlying the response to Cu2+ among different species are conserved. METHODS: Aurelia coerulea polyps and mice models were exposed to Cu2+ to assess its effects on survival status and organ damage. Transcriptomic sequencing, BLAST, structural analysis, and real-time quantitative PCR were carried out to analyze the similarities and differences in the molecular composition and response mechanisms between two species when exposed to Cu2+. RESULTS: Excessive Cu2+ exposure led to toxic effects on both A. coerulea polyps and mice. The polyps were injured at a Cu2+ concentration of 3.0 mg L-1. In the mice, increasing Cu2+ concentrations were correlated with, the degree of liver damage, which manifested as hepatocyte apoptosis. In the 300 mg L-1 Cu2+ group of mice, livers cell death was primarily triggered by the phagosome and Toll-like signaling pathways. We found the glutathione metabolism was significantly altered in response to copper stress in both A. coerulea polyps and mice. Moreover, the similarity of gene sequences enriched at the two same sites in this pathway was as high as 41.05 %-49.82 % and 43.61 %-45.99 % respectively. Among them, there was a conservative region in the structure of A. coerulea polyps GSTK1 and mice Gsta2, but the overall difference is large. CONCLUSION: Glutathione metabolism is a conserved copper response mechanism in evolutionary distant organisms such as A. coerulea polyps and mice, although mammals have a more complex regulatory network when it comes to copper-induced cell death.

The preventive effect of Glycyrrhiza polysaccharide on lipopolysaccharide-induced acute colitis in mice by modulating gut microbial communities.

Acute colitis is characterised by an unpredictable onset and causes intestinal flora imbalance together with microbial migration, which leads to complex parenteral diseases. Dexamethasone, a classic drug, has side effects, so it is necessary to use natural products without side effects to prevent enteritis. Glycyrrhiza polysaccharide (GPS) is an α-d-pyranoid polysaccharide with anti-inflammatory effects; however, its anti-inflammatory mechanism in the colon remains unknown. This study investigated whether GPS reduces the lipopolysaccharide (LPS)-induced inflammatory response in acute colitis. The results revealed that GPS attenuated the upregulation of tumour necrosis factor-α, interleukin (IL)-1ß, and IL-6 in the serum and colon tissues and significantly reduced the malondialdehyde content in colon tissues. In addition, the 400 mg/kg GPS group showed higher relative expressions of occludin, claudin-1, and zona occludens-1 in colon tissues and lower concentrations of diamine oxidase, D-lactate, and endotoxin in the serum than the LPS group did, indicating that GPS improved the physical and chemical barrier functions of colon tissues. GPS increased the abundance of beneficial bacteria, such as Lactobacillus, Bacteroides, and Akkermansia, whereas pathogenic bacteria, such as Oscillospira and Ruminococcus were inhibited. Our findings indicate that GPS can effectively prevent LPS-induced acute colitis and exert beneficial effects on the intestinal health.