Heat Stress Altered the Vaginal Microbiome and Metabolome in Rabbits

Study on Changes in Gut Microbiota and Microbiability in Rabbits at Different Developmental Stages

This study used feces from 0-day-old (36 rabbits), 10-day-old (119 rabbits), and 60-day-old (119 rabbits) offspring rabbits and their corresponding female rabbits (36 rabbits) as experimental materials. Using 16s rRNA sequencing, the study analyzed the types and changes of gut microbiota in rabbits at different growth and development stages, as well as the correlation between gut microbiota composition and the weight of 60-day-old rabbits. All experimental rabbits were placed in the same rabbit shed. Juvenile rabbits were fed solid feed at 18 days of age and weaned at 35 days of age. In addition to identifying the dominant bacterial phyla of gut microbiota in rabbits at different age stages, it was found that the abundance of Clostridium tertium and Clostridium paraputrificum in all suckling rabbits (10-day-old) was significantly higher than that in rabbits fed with whole feed (60-day-old) (p < 0.05), while the abundance of Gram-negative bacterium cTPY13 was significantly lower (p < 0.05). In addition, Fast Expected Maximum Microbial Source Tracing (FEAST) analysis showed that the contribution of female rabbits' gut microbiota to the colonization of offspring rabbits' gut microbiota was significantly higher than that of unrelated rabbits' gut microbiota (p < 0.05). The contribution of female rabbits' gut microbiota to the colonization of gut microbiota in 0-day-old rabbits was significantly higher than that to the colonization of gut microbiota in the 10- and 60-day-old rabbits (p < 0.05). Finally, the correlation between gut microbiota composition and body weight of 60-day-old rabbits was analyzed based on a mixed linear model, and six ASVs significantly affecting body weight were screened. The above results provide important theoretical and practical guidance for maintaining gut health, improving growth and development performance, and feeding formulation in rabbits.

The gut microbiota facilitate their host tolerance to extreme temperatures

BACKGROUND

Exposure to extreme cold or heat temperature is one leading cause of weather-associated mortality and morbidity in animals. Emerging studies demonstrate that the microbiota residing in guts act as an integral factor required to modulate host tolerance to cold or heat exposure, but common and unique patterns of animal-temperature associations between cold and heat have not been simultaneously examined. Therefore, we attempted to investigate the roles of gut microbiota in modulating tolerance to cold or heat exposure in mice.

RESULTS

The results showed that both cold and heat acutely change the body temperature of mice, but mice efficiently maintain their body temperature at conditions of chronic extreme temperatures. Mice adapt to extreme temperatures by adjusting body weight gain, food intake and energy harvest. Fascinatingly, 16 S rRNA sequencing shows that extreme temperatures result in a differential shift in the gut microbiota. Moreover, transplantation of the extreme-temperature microbiota is sufficient to enhance host tolerance to cold and heat, respectively. Metagenomic sequencing shows that the microbiota assists their hosts in resisting extreme temperatures through regulating the host insulin pathway.

CONCLUSIONS

Our findings highlight that the microbiota is a key factor orchestrating the overall energy homeostasis under extreme temperatures, providing an insight into the interaction and coevolution of hosts and gut microbiota.

Omics analysis of the effect of cold normal saline stress through gastric gavage on LPS induced mice

Cold stress is a significant environmental stimulus that negatively affects the health, production, and welfare of animals and birds. However, the specific effects of cold stimulation combined with lipopolysaccharide (LPS) on the mouse intestine remain poorly understood. Therefore, we designed this research to explore the effect of cold stimulation + LPS on mice intestine via microbiome and microbiota sequencing. Forty-eight mice were randomly divided into four experimental groups (n = 12): Control (CC), LPS-induced (CL), cold normal saline-induced (MC) and LPS + cold normal saline-induced (ML). Our results showed body weight was similar among different groups of mice. However, the body weight of mice in groups CC and CL were slightly higher compared to those in groups MC and ML. The results of gene expressions reflected that CL and ML exposure caused gut injury and barrier dysfunction, as evident by decreased ZO-1, OCCLUDIN (P < 0.01), and CASPASE-1 (P < 0.01) expression in the intestine of mice. Moreover, we found that cold stress induced oxidative stress in LPS-challenged mice by increasing malondialdehyde (MDA) accumulation and decreasing the antioxidant capacity [glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), total and antioxidant capacity (T-AOC)]. The cold stress promoted inflammatory response by increased IL-1β in mice treated with cold normal saline + LPS. Whereas, microbiome sequencing revealed differential abundance in four phyla and 24 genera among the mouse groups. Metabolism analysis demonstrated the presence of 4,320 metabolites in mice, with 43 up-regulated and 19 down-regulated in CC vs. MC animals, as well as 1,046 up-regulated and 428 down-regulated in ML vs. CL animals. It is Concluded that cold stress enhances intestinal damage by disrupting the balance of gut microbiota and metabolites, while our findings contribute in improving management practices of livestock in during cold seasons.

High-performance liquid chromatography-tandem mass spectrometry method for the analysis of N-oleoyl glycine and N-oleoyl alanine in brain and plasma

Interest has increased in the role of N-acyl amino acids in a variety of disease states and as potential pharmacotherapies. Recently, N-oleoyl glycine and N-oleoyl alanine have shown promise in reducing the rewarding effects of drugs of abuse and alleviating withdrawal signs in rodent models. Previously published methods for the quantitation of these analytes by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in tissue were part of extensive lipidomic panels which may result in limited sensitivity and selectivity and also reported low recovery. Presented is a method for the extraction and HPLC-MS/MS analysis of N-oleoyl glycine and N-oleoyl alanine. The bias and precision of the assay were determined to be within ± 20%. The method was shown to be reliable and robust, with over 90% recovery for the low-level analytes. Increasing concentrations of N-oleoyl glycine and N-oleoyl alanine were quantitated in mouse brain and plasma following exogenous administration. This method was developed to serve to support studies investigating the pharmacokinetics and involvement of N-oleoyl glycine and N-oleoyl alanine in drug dependence and other diseases.

Molecular association of Candida albicans and vulvovaginal candidiasis: focusing on a solution

Candida albicans-mediated vulvovaginal candidiasis (VVC) is a significant challenge in clinical settings, owing to the inefficacy of current antifungals in modulating virulence, development of resistance, and poor penetration into the biofilm matrix. Various predisposition factors are molecular drivers that lead to the dysbiosis of normal microflora of the vagina, upregulation of central metabolic pathways, morphogenesis, hyphal extension, adhesion, invasion, and biofilm formation leading to chronic infection and recurrence. Hence, it is crucial to understand the molecular mechanism behind the virulence pathways driven by those drivers to decode the drug targets. Finding innovative solutions targeting fungal virulence/biofilm may potentiate the antifungals at low concentrations without affecting the recurrence of resistance. With this background, the present review details the critical molecular drivers and associated network of virulence pathways, possible drug targets, target-specific inhibitors, and probable mode of drug delivery to cross the preclinical phase by appropriate in vivo models.

Effect of Slow-Release Urea Partial Replacement of Soybean Meal on Lactation Performance, Heat Shock Signal Molecules, and Rumen Fermentation in Heat-Stressed Mid-Lactation Dairy Cows

This study aimed to assess the effects of partially substituting soybean meal in the diet with slow-release urea (SRU) on the lactation performance, heat shock signal molecules, and environmental sustainability of heat-stressed lactating cows in the middle stage of lactation. In this study, 30 healthy Holstein lactating dairy cattle with a similar milk yield of 22.8 ± 3.3 kg, days in milk of 191.14 ± 27.24 days, and 2.2 ± 1.5 parity were selected and randomly allocated into two groups. The constituents of the two treatments were (1) basic diet plus 500 g soybean meal (SM) for the SM group and (2) basic diet plus 100 g slow-release urea and 400 g corn silage for the SRU group. The average temperature humidity index (THI) during the experiment was 84.47, with an average THI of >78 from day 1 to day 28, indicating the cow experienced moderate heat stress conditions. Compared with the SM group, the SRU group showed decreasing body temperature and respiratory rate trends at 20:00 (p < 0.1). The substitution of SM with SRU resulted in an increasing trend in milk yield, with a significant increase of 7.36% compared to the SM group (p < 0.1). Compared to the SM group, AST, ALT, and γ-GT content levels were significantly increased (p < 0.05). Notably, the levels of HSP-70 and HSP-90α were significantly reduced (p < 0.05). The SRU group showed significantly increased acetate and isovalerate concentrations compared with the SM group (p < 0.05). The prediction results indicate that the SRU group exhibits a significant decrease in methane (CH4) emissions when producing 1 L of milk compared to the SM group (p < 0.05). In summary, dietary supplementation with SRU tended to increase the milk yield and rumen fermentation and reduce plasma heat shock molecules in mid-lactation, heat-stressed dairy cows. In the hot summer, using SRU instead of some soybean meal in the diet alleviates the heat stress of dairy cows and reduces the production of CH4.

Comparative Analysis of the Pre-Parturition and Post-Parturition Genital Tract Microbiota in Plateau Bangor Sewa Sheep

(1) Background: Bangor Sewa sheep are an economically significant livestock species on the plateau. The roles of microbiota in reproduction are complex and critical for animal health. But little is known currently about the microbiome of plateau Bangor Sewa sheep. The purpose of this study was to discover the changes in the genital tract microbiota of pre- and post-partum Bangor Sewa sheep. (2) Methods: Samples from the birth canal were obtained for 16S rRNA sequencing, three days before and after delivery, respectively. (3) Results: The results showed that there was a noticeable difference in three phyla and 74 genera between the pre- and post-parturition groups in the microbiota of Bangor Sewa sheep. The changes included a decrease in the abundance of genera related to health (unclassified_Cellulomonadaceae, Cellulomonas, Fibrobacti, Flavobacterium, Eubacterium_ventriosum_group, Acetitomaculum, Aeromicrobium, Dietzia, Romboutsia, Ruminococcus, etc.) and an increased abundance of negatively related genera (Nocardioides, unclassified_Clostridia, Sphingobacteriaceae, unclassified_Ruminococcaceae, Prevotellaceae_UCG_004, Micromonospora, Streptococcus, Facklamia, Bosea, etc.) spp. (4) Conclusions: Microbes can serve as indicators of the physical state of Bangor Sewa sheep. These findings laid the foundation for deciphering the effects of microbial changes during birth on the reproductive health of plateau Bangor Sewa sheep.

Study on the mechanism of anti-hepatic fibrosis of Glycyrrhiza Uralensis-Salvia miltiorrhiza prescription based on serum and urine metabolomics and network pharmacology

Hepatic fibrosis (HF) is a kind of chronic epidemic liver disease. Glycyrrhiza Uralensis and Salvia Miltiorrhiza (GUSM), traditional Chinese medicine, has the obvious clinical treatment of liver fibrosis. This study aimed to investigate the mechanisms of GUSM against HF by an integrated strategy combining untargeted metabolomics with network pharmacology. The results showed that GUSM prescription can improve the morphology and structure of liver tissue, inhibit the proliferation of collagen fibers and reducing the inflammatory response of the liver and so on. Endogenous metabolites and HF-related potential biomarkers in serum and urine were detected by ultra-high-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS). The metabolic pathways were enriched by MetaboAnalyst. GUSM prescription showed an antifibrotic effect on rats by regulating metabolic pathways, mainly pentose and glucuronate interconversions and arachidonic acid metabolism. Network pharmacology was then applied to find 42 overlapping targets of GUSM-HF. Quercetin was found to be the main active component and STAT3 was the main active target in GUSM prescription. Molecular docking showed high affinities between quercetin and STAT3. Therefore, GUSM has protective effects on HF by regulating the metabolism and different signaling pathways. The work also shows that the metabolomic and network pharmacology methods are promising tools to gain insight into the efficacy and mechanism research of traditional Chinese medicines.