5-HT attenuates chronic stress-induced cognitive impairment in mice through intestinal flora disruption.

BACKGROUND: The microbiota-gut-brain axis plays an important role in the development of depression. The aim of this study was to investigate the effects of 5-HT on cognitive function, learning and memory induced by chronic unforeseeable mild stress stimulation (CUMS) in female mice. CUMS mice and TPH2 KO mice were used in the study. Lactococcus lactis E001-B-8 fungus powder was orally administered to mice with CUMS. METHODS: We used the open field test, Morris water maze, tail suspension test and sucrose preference test to examine learning-related behaviours. In addition, AB-PAS staining, immunofluorescence, ELISA, qPCR, Western blotting and microbial sequencing were employed to address our hypotheses. RESULTS: The effect of CUMS was more obvious in female mice than in male mice. Compared with female CUMS mice, extracellular serotonin levels in TPH2 KO CUMS mice were significantly reduced, and cognitive dysfunction was aggravated. Increased hippocampal autophagy levels, decreased neurotransmitter levels, reduced oxidative stress damage, increased neuroinflammatory responses and disrupted gut flora were observed. Moreover, L. lactis E001-B-8 significantly improved the cognitive behaviour of mice. CONCLUSIONS: These results strongly suggest that L. lactis E001-B-8 but not FLX can alleviate rodent depressive and anxiety-like behaviours in response to CUMS, which is associated with the improvement of 5-HT metabolism and modulation of the gut microbiome composition.

Effect of splenic transfer factor on the development of intestinal mucosal barrier in laying hens.

BACKGROUND: The aim of this study was to investigate the effects of different doses of chicken spleen transfer factor (TF) on the structure of intestinal epithelial cells in different age groups. One-day-old White Leghorns laying hens were randomly divided into four groups: three groups were administered TF at different dosages (0.10, 0.25 or 1.00 mL) and a fourth group was set as control (administered saline, 1.00 mL). Using hematoxylin and eosin staining, high-throughput sequencing, microbiota analysis, quantitative polymerase reaction and western blotting. RESULTS: We measured the effects of different doses of TF on the following: intestinal mucosal epithelial tissue morphology, intestinal mucosal epithelial barrier-related gene expression profiles, and intestinal epithelial tight junction gene protein levels. The collected data show that TF can improve the absorption of nutrients by increasing villus height and crypt depth, and regulate intestinal flora disorders. Furthermore, we verified that the expression of the claudin and occludin tight junctions between intestinal epithelial cells was increased with TF. this research is very important for focusing on the structure and gene expression of intestinal tissues. CONCLUSION: The results provide a scientific rationale for feeding and nutrition programs for green and healthy farming, as well as technical support to improve the production efficiency of the livestock and poultry breeding industry. © 2022 Society of Chemical Industry.

Effect of Sleeve Gastrectomy on Bone Metabolism and Serum 5-Hydroxytryptamine in Obese Rats.

BACKGROUND Studies have shown that bariatric surgery, such as sleeve gastrectomy (SG), has an adverse effect on bone, including decreased bone mineral density (BMD) and bone metabolism. Peripheral 5-hydroxytryptamine (5-HT) has an adverse regulatory effect on bone formation. Here, we assessed changes in bone metabolism and whether 5-HT is involved in the effect of SG on bone metabolism. MATERIAL AND METHODS A rat model of obesity was established using Wistar rats. After successful modeling, rats were randomly assigned to 2 groups - the SG group and the Sham group - with 10 rats in each group. We then performed sleeve gastrectomy or sham operation. Bone metabolic markers and BMD of rats were measured at 2 and 16 weeks after the operation and the level of 5-HT in serum was determined. Rats were killed at 16 weeks after the operation, and bones of the hind limbs were harvested to measure 5-HT by immunofluorescence. RESULTS BMD was decreased and bone metabolism demonstrated a trend of bone destruction in the rats after SG. A significantly increasing trend in the level of serum 5-HT was found, and bone immunofluorescence showed increased expression of 5-HT. CONCLUSIONS BMD was decrease and bone metabolism demonstrated a trend of bone destruction after SG. SG can affect the level of 5-HT in serum or bone tissue and the 5-HT may be involved in the process through which SG affects bone metabolism.

Regulation by Hsp27/P53 in testis development and sperm apoptosis of male cattle (cattle-yak and yak).

Heat shock protein 27 (Hsp27)/protein 53 (P53) plays an important role in testis development and spermatozoa regulation, but the relationship between Hsp27/P53 and infertility in cattle is unclear. Here, we focus on male cattle-yak and yak to investigate the expression and localization of Hsp27/P53 in testis tissues and to explore the influence of Hsp27/P53 on infertility. In our study, a total of 54 cattle (24 cattle-yak and 30 yak) were examined. The Hsp27 and P53 messenger RNA (mRNA) of cattle-yak were cloned, and amino acid variations in Hsp27 and P53 were found; the variations led to differences in the protein spatial structure compared with yak. We used real-time quantitative polymerase chain reaction and western blot to investigate whether the expression of Hsp27/P53 mRNA and protein was different in cattle-yak and yak. We found that the expression levels of Hsp27/P53 mRNA and protein were different in the testis developmental stages and the highest expression was observed in testicles during adulthood. Moreover, the Hsp27 expression was significantly higher in yak, whereas P53 expression was higher in cattle-yak (p < 0.01). On this basis, we detected the location of Hsp27/P53 in the testis by immunohistochemistry and immunofluorescence. The results demonstrated that Hsp27 was located in spermatogenic cells at different developmental stages and mesenchymal cells of the yak testicles. However, P53 was located in the primary spermatocyte and interstitial cells of the cattle-yak testicles. In summary, our study proved that the expression of Hsp27/P53 differed across the testis developmental stages and the expression of P53 was higher in the testis of cattle-yak, which suggested that the infertility of cattle-yak may be caused by the upregulation of P53.