Coprophagy Prevention Decreases the Reproductive Performance and Granulosa Cell Apoptosis via Regulation of CTSB Gene in Rabbits

Unraveling the Role of Cathepsin B Variants in Polycystic Ovary Syndrome: Insights from a Case-Control Study and Computational Analyses

Polycystic ovary syndrome (PCOS) occurs in women of reproductive age, impairing reproductive and metabolic processes. Variations in the cathepsin B (CTSB) gene can influence the disease prognosis by changing the activity, stability, or expression. These single-nucleotide polymorphisms (SNPs) can affect critical cellular functions like the deposition of extracellular matrix, inflammation, and tissue repair, leading to the development of multifactorial diseases. Our study aims to investigate the association between PCOS risk and CTSB SNPs. In this case-control study, 150 PCOS cases and 150 healthy women were enrolled. Genotyping was conducted using the PCR-RFLP method. Different computational databases were used to predict the impact of variations on the splicing sites. Regarding rs12898, the codominant homozygous (GG vs. AA) and recessive (GG vs. AA + AG) inheritance models reduced PCOS risk by 72% and 71%, respectively. PCOS risk was increased by 2.81, 2.94, 1.62, and 2.20 folds in the codominant (TT vs. CC), recessive (TT vs. CC + CT), T vs. C (rs8898), and T vs. C (rs3779659) modes, respectively. Based on haplotype analysis, Ars12898Trs8898Crs3779659, and Ars12898Crs8898Trs3779659 haplotypes significantly enhance PCOS risk by 1.57 and 3.34 folds, respectively. Furthermore, the interaction analysis indicated that AGrs12898/TTrs8898/CCrs3779659 and AAs12898/TTrs8898/CCrs3779659 genotype combinations strongly correlated with high PCOS risks by 2.59 and 4.20 folds, respectively. The CTSB rs12898 G > A and rs8898 C > T can potentially create or disrupt binding sites for several splicing factors. CTSB rs12898, rs8898, and rs3779659 SNPs were associated with PCOS risk in our population. Larger sample sizes will be necessary to confirm these findings and investigate other potential causal factors involved in PCOS etiology.

Progestin and adipoQ receptor 7 (PAQR7) mediate the anti-apoptotic effect of P4 on human granulosa cells and its deficiency reduces ovarian function in female mice

PURPOSE

PAQR7 plays a key role in cell apoptosis as a progesterone membrane receptor. The physiological mechanism of PAQR7 in ovarian function and its anti-apoptotic action in mammals remain poorly understood.

METHODS

We first added 0.2 µM aminoglutethimide (AG), an inhibitor of endogenous progesterone (P4) secretion, and transfected siPAQR7 co-incubated with P4 in human KGN cells to identify granulosa cell apoptosis, respectively. Additionally, we used Paqr7 knockout (PAQR7 KO) mice to assess the role of PAQR7 in the ovary.

RESULTS

The PAQR7 deficiency significantly increased apoptosis of KGN cells, and this significant difference disappeared following P4 supplementation. The Paqr7-/- female mice showed a prolonged estrous cycle, reduced follicular growth, increased the number of atresia follicles, and decreased the concentrations of E2 and AMH. The litters, litter sizes, and spontaneous ovulation in the Paqr7-/- mice were significantly decreased compared with the Paqr7+/+ mice. In addition, we also found low expression of PAQR7 in GCs from human follicular fluids of patients diagnosed with decreased ovarian reserve (DOR) and ovaries of mice with a DOR-like phenotype, respectively.

CONCLUSIONS

The present study has identified that PAQR7 is involved in mouse ovarian function and fertilization potential. One possible mechanism is mediating the anti-apoptotic effect of P4 on GC apoptosis via the BCL-2/BAX/CASPASE-3 signaling pathway. The mechanism underlying the effect of PAQR7 on ovarian development and aging remains to be identified.

Impact of coprophagy prevention on the growth performance, serum biochemistry, and intestinal microbiome of rabbits

BACKGROUND

Coprophagy plays a vital role in maintaining growth and development in many small herbivores. Here, we constructed a coprophagy model by dividing rabbits into three groups, namely, control group (CON), sham-coprophagy prevention group (SCP), and coprophagy prevention group (CP), to explore the effects of coprophagy prevention on growth performance and cecal microecology in rabbits.

RESULTS

Results showed that CP treatment decreased the feed utilization and growth performance of rabbits. Serum total cholesterol and total triglyceride in the CP group were remarkably lower than those in the other two groups. Furthermore, CP treatment destroyed cecum villi and reduced the content of short-chain fatty acids (SCFAs) in cecum contents. Gut microbiota profiling showed significant differences in the phylum and genus composition of cecal microorganisms among the three groups. At the genus level, the abundance of Oscillospira and Ruminococcus decreased significantly in the CP group. Enrichment analysis of metabolic pathways showed a significantly up-regulated differential metabolic pathway (PWY-7315, dTDP-N-acetylthomosamine biosynthesis) in the CP group compared with that in the CON group. Correlation analysis showed that the serum biochemical parameters were positively correlated with the abundance of Oscillospira, Sutterella, and Butyricimonas but negatively correlated with the abundance of Oxalobacte and Desulfovibrio. Meanwhile, the abundance of Butyricimonas and Parabacteroidesde was positively correlated with the concentration of butyric acid in the cecum.

CONCLUSIONS

In summary, coprophagy prevention had negative effects on serum biochemistry and gut microbiota, ultimately decreasing the growth performance of rabbits. The findings provide evidence for further revealing the biological significance of coprophagy in small herbivorous mammals.

Coprophagy Prevention Affects the Reproductive Performance in New Zealand White Rabbits Is Mediated through Nox4-ROS-NFκB Pathway

Coprophagy is of great significance to the growth, development, and reproductive performance of rabbits. This study is aimed at exploring the effect of coprophagy on the reproductive performance of New Zealand white rabbits by coprophagy prevention (CP). The results showed that CP treatment significantly decreased the growth and development performance of female rabbits and the live birth rate of embryos. The results of blood biochemical indexes showed that CP treatment significantly increased the contents of serum ALB, ALP, and MDA, while serum SOD activity was significantly decreased. Transcriptome analysis showed that GO terms were mainly enriched in transport function and reproductive function after CP treatment. In addition, KEGG results showed that inflammation related signal pathways were activated and the expression level of genes related to tight junction proteins was downregulated by CP treatment. Concurrently, western blot further confirmed the results of KEGG. In short, fecal feeding is an important survival strategy for some small rodents, coprophagy prevention will affect the inflammatory level of the body, change the oxidative stress level of the body, and then activate NOX4-ROS-NF-κB pathway, increase the expression level of adhesion protein ICAM-1 and VCAM-1, lead to the damage of uterine epithelial barrier, and then affect the reproductive performance of rabbits.