The intestinal barrier is vital for preventing inflammatory bowel disease (IBD). The objectives of this study were to assess whether the Lactobacillus rhamnosus CY12 could alleviate oxidative stress, inflammation, and the disruption of tight junction (TJ) barrier functions induced by lipopolysaccharide (LPS), and therefore to explore the potential underlying molecular mechanisms. Our results showed that LPS-induced Cancer coli-2 (Caco-2) cells significantly increased the levels of reactive oxygen species (ROS), lactate dehydrogenase, inflammatory cytokines interleukin-1β, interleukin-6, interleukin-8, and tumor necrosis factor-α (IL-1β, IL-6, IL-8, and TNF-α), and the cell apoptosis rate while decreasing the levels of TJ proteins occludin, zonula occludens-1 (ZO-1), and claudin and antioxidant enzymes, such as catalase, superoxide dismutase, and glutathione peroxidase(CAT, SOD, and GSH-Px) (p < 0.05). However, Lactobacillus rhamnosus CY12 could relieve cytotoxicity, apoptosis, oxidative stress, and pro-inflammatory cytokine expressions, and also inhibit the Toll-like receptor 4/nuclear factor kappa-B(TLR4/NF-κB) signaling pathway. Furthermore, the gene expression of antioxidant enzymes, as well as the mRNA and protein expressions of TJ proteins, was improved. Particularly, the concentration of 10⁸ cfu/mL significantly prevented the inflammatory injury induced by LPS in Caco-2 cells (p < 0.05). These findings support a potential application of Lactobacillus rhamnosus CY12 as a probiotic to prevent LPS-induced intestinal injury and treat intestinal barrier dysfunction.

Background: Rumen microbes play an important role in ruminant energy supply and animal performance. Previous studies showed that the rumen microbiome of Mongolian cattle has adapted to degrade the rough forage to provide sufficient energy to tolerate the harsh desert ecological conditions. However, little is known about the succession of rumen microbes in different developmental stages of post-weaning Mongolian cattle. Methods: Here, we examined the succession of the rumen microbial composition and structure of 15 post-weaning Mongolian cattle at three developmental stages i.e., 5 months (RM05), 18 months (RM18) and, 36 months (RM36) by using the 16S rRNA gene sequencing method. Results: We did not find any age-dependent variations in the ruminal concentrations of any volatile fatty acid (VFA) of Mongolian cattle. The diversity of the rumen bacterial community was significantly lower in RM05 group, which reached to stability with age. Bacteroidetes and Firmicutes were the two dominant phyla among all age groups. Phylum Actinobacteria was significantly higher in RM05 group, phyla Spirochaetes, and Tenericutes were highly abundant in RM18 group, and phyla Proteobacteria and Epsilonbacteraeota were enriched in RM36 group. Genera Prevotella_1, Bacteroides, and Bifidobacterium were abundant in RM05 group. The short chain fatty acid (SCFA) producing bacteria Rikenellaceae_RC9_gut_group showed high abundance in RM18 group and fiber degrading genus Alloprevotella was highly abundant in RM36 group. Random forest analysis identified Alloprevotella, Ileibacterium, and Helicobacter as important age discriminatory genera. In particular, the genera Ruminococcaceae_UCG-005, Bacteroides, Saccharofermentans, and Fibrobacter in RM05, genera [Eubacterium] coprostanoligenes_group, Erysipelotrichaceae_UCG-004, Helicobacter, Saccharofermentans, Papillibacter, and Turicibacter in RM18, and genera Rikenellaceae_RC9_gut_group, Lachnospiraceae_AC2044_group, and Papillibacter in RM36 showed the top interactions values in the intra-group interaction network. Conclusions: The results showed that rumen microbiota of Mongolian cattle reached to stability and maturity with age after weaning. This study provides some theoretical evidence about the importance of functional specific rumen bacteria in different age groups. Further studies are needed to determine their actual roles and interactions with the host.

With the implementation of modern scientific protocols, the average human lifespan has significantly improved, but age-related problems remain a challenge. With the advent of ageing, there are alterations in gut microbiota and gut barrier functions, weak immune responses, increased oxidative stress, and other age-related disorders. This review has highlighted and discussed the current understanding on the significance of gut microbiota dysbiosis and ageing and its inherent effects against age-related oxidative stress as well as on the gut health and gut-brain axis. Further, we have discussed the key mechanism of action of Lactobacillus strains in the longevity of life, alleviating gut dysbiosis, and improving oxidative stress and inflammation to provide an outline of the role of Lactobacillus strains in restoration of gut microbiota dysbiosis and alleviating certain conditions during ageing. Microbiota-targeted interventions of some characterized strains of probiotic Lactobacillus for the restoration of gut microbial community are considered as a potential approach to improve several neurological conditions. However, very limited human studies are available on this alarmed issue and recommend further studies to identify the unique Lactobacillus strains with potential anti-ageing properties and to discover its novel core microbiome-association, which will help to increase the therapeutic potential of probiotic Lactobacillus strains to ageing.

The objective of this study was to investigate the effects of different dietary energy levels on serum concentrations of growth hormone (GH) and insulin-like growth factor 1 (IGF-1), as well as gene expression of their associated binding proteins and receptors in yak. Fifteen adult male yaks with BW of 276.1 ± 3.5 kg were allotted in three dietary groups and were fed with low (LE), medium (ME), and high energy (HE) level diet having different NEg of 5.5 MJ/kg, 6.2 MJ/kg, 6.9 MJ/kg, respectively. The effects of these treatments on ADG, BW, ADFI, and feed conversion ratio were significant (p < 0.05) throughout the experimental period. Serum GH concentration decreased (p < 0.05) with an increase in dietary energy level on d 30 and d 60. While IGF-1 concentration was higher (p < 0.05) in ME group, as compared to LE and HE groups on d 60. The expression level of growth hormone receptor (GHR) was decreased (p < 0.001) and IGF-1 was increased with the increase in the dietary energy level. The relative expression of insulin-like growth factor binding protein 3 (IGFBP-3) was higher (p < 0.001) in ME and HE groups, except the LE group. In conclusion, our findings provide a first insight into the combined effect of GH and IGF-1 in controlling the metabolism and productivity of yak. It also showed that medium energy level diet contributed to promote growth performance of yak during the cold season.

Histological examination of testes is essential for understanding infertility, sex development, and growth. Therefore, to understand the histomorphology of testes at different developmental stages, we performed hematoxylin and eosin staining of Yak testis. Our results revealed that the diameters of spermatogenic cells and their nuclei were significantly larger (p < 0.05) in the testis at six years compared to at six and 18 months. No significant difference was noted between 30 months and six years. The study was designed to compare the expression profile of LHB in Datong yak. The expression pattern of LHB was explored using quantitative PCR, semi-quantitative PCR, molecular bioinformatic, and Western blot analysis. Our observations indicated that expression of LHB was significantly higher (p < 0.05) in the testis of Datong yak. Western blotting indicated that the molecular mass of LHB protein was 16 kDa in yak. The protein encoded by yak LHB included conserved cysteine-knot domain regions. The high expression of LHB in testis indicated that LHB may be vital for the development of male gonads and the fertility of Datong yak.

Background: The gut microbiota plays an important role in the health and production of animals. However, little information is available on the dynamic variations and comparison of intestinal microbiota in post-weaning yak calves living on the QTP. Methods: We explored the fecal bacterial microbiota succession of yak calves at different months after early weaning (60 d) compared with cattle calves by 16S rRNA gene amplicon sequencing and functional composition prediction. Results: We found no significant difference in blood biochemical parameters related to glucose and lipid metabolism between yaks and calves in different months after weaning. The core fecal bacterial microbiota from both species of calves was dominated by Ruminococcaceae, Rikenellaceae, and Bacteroidaceae. The fecal microbial community has a great alteration within the time after weaning in both cattle and yak calves, but cattle showed a larger change. After five months, the microbiota achieves a stable and concentrated state. This is also similar to the functional profile. Conclusions: Based on the exploration of dynamic changes in the fecal microbiota at an early stage of life, our results illustrated that there were no negative effects of intestinal microbiota succession on yak calves when early weaning was employed.