Effects of grape seed procyanidins on the lipid metabolism of growing-finishing pigs based on transcriptomics and metabolomics analyses.

This study investigated how lipid metabolism in the longissimus thoracis is influenced by the diet supplemented with grape seed procyanidins (GSPs) in growing-finishing pigs. Forty-eight crossbred pigs were randomly assigned to four groups, each receiving a basal diet, or basal diet added with 150, 200, and 250 mg/kg GSPs. Transcriptomics and metabolomics were employed to explore differential gene and metabolite regulation. The expression of key lipid metabolism-related genes was tested via qRT-PCR, and the lipid and fatty acid composition of the longissimus thoracis were determined. Dietary GSPs at different concentrations upregulated lipoprotein lipase (LPL), which is involved in lipolysis, and significantly increased the mRNA expression levels of carnitine palmitoyltransferase-1B (CPT1B) and cluster of differentiation 36 (CD36), implicated in transmembrane transport of fatty acids. Dietary supplementation of GSPs at 200 or 250 mg/kg markedly reduced total cholesterol and triglyceride content in longissimus thoracis. Dietary GSPs significantly decreased the contents of low-density lipoprotein cholesterol and saturated fatty acids, while increasing unsaturated fatty acids. In conclusion, GSPs may regulate lipid metabolism, reducing cholesterol level, and improving fatty acid composition in the longissimus thoracis of growing-finishing pigs. Our findings provide evidence for the beneficial effects of GSPs as pig feed additives for improving lipid composition.

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.

Effects of high fructose corn syrup on intestinal microbiota structure and obesity in mice.

High fructose corn syrup (HFCS)-associated health problems have raised concerns. We investigated the effects of HFCS-containing drinking water on body fat, intestinal microbiota structure of mice, and the relationships between them. HFCS drinking water significantly increased body fat content and altered the intestinal microbiome. The Christensenellaceae R-7 group negatively correlated with body weight, perirenal fat, epididymal fat, and liver fat percentage.

Combined analysis of microbial community and microbial metabolites based on untargeted metabolomics during pig manure composting.

Compost has been widely used in agriculture in recent years, but the nutrients it provides are far from enough for plant growth. Therefore, it is necessary to systematically explore the fermentation process of composting. In this study, the succession of microbial community and metabolite characteristics in compost were analyzed by using microbial sequencing and metabolomics techniques. The results showed that compared with mesophilic phase and cooling phase, the richness and diversity of bacterial community decreased in thermophilic phase. At the genus level, Pseudomonas (8.90%), Lactobacillus (3.99%), Bacteroidetes (3.39%), Flavobacterium (3.25%) and Prevotella (Prevotella_9, 2.33%, Prevotellaceae_NK3B31_group, 2.44%) were the dominant genera in the pig manure composting. The abundance of Pseudomonas and Flavobacterium increased significantly while Lactobacillus and Prevotella were significantly decreased after composting, and the abundance of Bacteroidetes increased first and then decreased. Fatty acyls, sterol lipids, glycerophospholipids, polyketides and prenol lipids were common microbial metabolites in compost. Moreover, the linoleic acid metabolic pathway was significantly enriched in the three stages of composting, and linoleic acid metabolism might be the primary function of the microbial community in composting. The network analysis showed that between the microbial communities or between the microbial community and metabolites were closely related to each other.

Follicular fluid meiosis-activating sterol (FF-MAS) promotes meiotic resumption via the MAPK pathway in porcine oocytes.

Follicular fluid meiosis-activating sterol (FF-MAS) exerts beneficial effects on the meiotic resumption of mammalian oocytes and their subsequent early embryonic development, but the signaling pathway underlying these effects has not been elucidated. Therefore, the objective of the present study was to investigate whether the mitogen-activated protein kinase (MAPK) pathway is involved in the FF-MAS-induced in vitro resumption of meiosis in porcine oocytes. Porcine cumulus oocyte complexes (COCs) were allocated in several groups cultured in TCM-199 medium with different concentration of AY 9944-A-7 (20, 30, 40 µmol/L) or ketoconazole (20 µmol/L) to increase or decrease endogenous accumulation of FF-MAS. Each experimental condition was repeated at least six times. After maturation for 44 h, the resumption of meiosis was assessed by the frequency of germinal vesicle breakdown (GVBD) and the first polar body (PBI) extrusion, The relative expressions of related genes in MAPK pathway [c-mos, mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase 1/2 (ERK1/2)] at both transcriptional and translational levels were detected to investigate the kinetic trend of expression throughout oocyte maturation in vitro in response to the addition of AY 9944-A-7 or ketoconazole to the maturation medium. Results indicated that AY 9944-A-7 promoted, while ketoconazole inhibited, the in vitro maturation (IVM) of porcine oocytes. Relative expression of meiosis related genes was upregulated by AY 9944-A-7 and downregulated by ketoconazole. With extended culturing time, c-mos mRNA expression levels reached their peak at 12 h of maturation and decreased gradually thereafter, while MEK, ERK1 and ERK2 expression increased after an initial decrease peaking at 44 h of culture in the AY 9944-A-7-group. And the trend of the protein expression of c-mos, MEK, ERK1/2 was basically consistent with the mRNA expression of these genes. These results imply that the endogenous accumulation of FF-MAS is beneficial to resumption of meiosis in porcine oocytes and that MAPK signaling is involved in FF-MAS-induced meiotic resumption.

Coordinated microRNA and messenger RNA expression profiles for understanding sexual dimorphism of gonads and the potential roles of microRNA in the steroidogenesis pathway in Nile tilapia (Oreochromis niloticus).

Sexual dimorphism is a widespread phenomenon in animals. However, the potential role of microRNAs (miRNAs) in regulating this dimorphism is not fully understood. In our study, we used an integrated approach to identify functional targets of miRNA by combining the paired expression profiles of miRNAs and messenger RNAs (mRNAs) in ovaries and testes of young Nile tilapia, Oreochromis niloticus. The results revealed that 67 upregulated and nine downregulated miRNAs and 2299 upregulated and 3260 downregulated genes were identified in the ovary compared with those in the testis (P < 0.01). The target genes of differentially expressed miRNAs were predicted and overlapped with the differentially expressed mRNAs. Furthermore, Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted in these coincident genes. By correlating miRNA-mRNA and predicting computational target, two types of negatively regulatory miRNA-mRNA correlations (upregulated or downregulated miRNA and downregulated or upregulated mRNA) were obtained. Seven functional miRNA-target gene pairs, miR-17-5p/DMRT1, miR-20a/DMRT1, miR-138/CYP17A2, miR-338/CYP17A2, miR-200a/CYP17A2, miR-456/AMH, and miR-138/AMH, were predicted at the sequence level and further detected by real-time polymerase chain reaction on the basis of the significantly negative relationships. Our results suggest that the integrated analysis of miRNA and mRNA expression profiling can provide novel insights into the molecular mechanism of sexual dimorphism.

Effects of AY9944 A-7 on gonadotropin-induced meiotic resumption of oocytes and development of parthenogenetic embryos in sheep.

Follicular fluid meiosis-activating sterol (FF-MAS), an intermediate in the cholesterol biosynthetic pathway, has been identified as a compound that induces the resumption of meiosis in mammalian oocyte. Follicular fluid meiosis-activating sterol is converted to testis meiosis-activating sterol by a sterol Δ14-reductase. An inhibitor of Δ14-reductase and Δ7-reductase, AY9944 A-7, causes accumulation of FF-MAS by inhibiting its metabolism. The objective of this research was to investigate the specific contribution of AY9944 A-7 on gonadotropin-induced meiotic resumption and its interactive effects with FSH or LH on meiotic maturation of oocytes and preimplantation development of parthenogenetic embryo in sheep by addition of AY9944 A-7 during IVM to cause accumulation of FF-MAS. First, ovine cumulus-oocyte complexes (COCs) were cultured in the presence of FSH (10 µg/mL), LH (10 µg/mL), AY9944 A-7 (20 µmol/L), FSH (10 µg/mL)+AY9944 A-7 (20 µmol/L), or LH (10 µg/ml) + AY9944 A-7 (20 µmol/L) with an inhibitor hypoxanthine (Hx) to prevent spontaneous meiosis of oocytes. The resumption of meiosis was assessed by the frequency of germinal vesicle breakdown and the first polar body (PBI) extrusion. The kinetics of gonadotropin and AY9944 A-7-induced meiotic resumption in vitro was also evaluated in the study. The numbers of oocytes resuming meiosis and undergoing germinal vesicle breakdown were counted after the COCs were cultured for 2, 4, 8, 12, 16, 20, and 24 hours. Matured oocytes extruding PBI were selected for parthenogenetic activation, and the percentages developing to the two-cell stage and blastocyst stage were recorded as indicators of parthenogenetic embryo developmental competence. It was observed that FSH could induce the resumption of meiosis of ovine COCs cultured in the presence of Hx, but LH could not. AY9944 A-7 had a synergistic effect with FSH on nuclear maturation and developmental competence of embryos produced by parthenogenetic activation, whereas it had no added advantage on LH action. However, the kinetics of meiotic resumption after AY9944 A-7 stimulation was remarkably delayed when compared with FSH-induced maturation. In conclusion, the current study suggested that AY9944 A-7 supplementation in IVM medium optimized the beneficial effects of FSH on meiotic maturation of ovine oocytes and subsequent developmental competence of embryos produced by parthenogenetic activation. This work had important potential for developing a novel technique in IVM of ovine oocytes.

AY9944 A-7 promotes meiotic resumption and preimplantation development of prepubertal sheep oocytes maturing in vitro.

Follicular fluid meiosis-activating sterol (FF-MAS), an intermediate in the cholesterol biosynthetic pathway, has been identified as a compound that induces the resumption of meiosis in mammalian oocyte. FF-MAS is converted to testis meiosis-activating sterol by a sterol Δ14-reductase. An inhibitor of Δ14-reductase and Δ7-reductase, AY9944 A-7, causes accumulation of FF-MAS by inhibiting its metabolism. The objective of this study was to determine the effects of AY9944 A-7 supplementation to oocyte maturation media on prepubertal sheep oocyte meiotic resumption and subsequent preimplantation development of embryos. Prepubertal sheep oocytes isolated at the germinal vesicle stage from their follicles were cultured with 0, 10, 20, 30, and 40 µM AY9944 A-7 for 24 hours in media with or without a meiotic inhibitor hypoxanthine (Hx, 4 mM). The resumption of meiosis was assessed by the frequency of germinal vesicle breakdown and the first polar body (PBI) extrusion. After maturation for 24 hours, oocytes with PBI were inseminated in vitro, and the percentages developing to the two-cell stage and blastocyst stage were measured as indicators of early embryonic developmental competence. AY9944 A-7 induced maturation of sheep cumulus-oocyte complexes with optimal concentrations of 10 and 20 µM both in Hx-inhibited meiotic maturation and spontaneous maturation, whereas AY9944 A-7 with any concentrations had no significant effect on that of denuded oocytes and split cumulus-oocyte complexes. Furthermore, maturing oocytes treated with either 10 or 20 µM AY9944 A-7 dramatically increased the percentages of ovine embryos developing to the two-cell stage and blastocyst stage. Higher concentrations of AY9944 A-7, 30 and 40 µM, were detrimental to oocytes and led to their degeneration. The present findings indicated for the first time that AY9944 A-7 was not only able to promote meiotic maturation, both Hx-inhibited and spontaneous, but also enhanced preimplantation developmental competence of prepubertal sheep oocytes maturing in vitro.