The protective role of phlorizin against lipopolysaccharide-induced acute orchitis in mice associated with changes in gut microbiota composition.

Objective: Orchitis is a common reproductive disease of male animals, which has serious implications to human and animal reproduction. Additionally, phlorizin (PHN), a common polyphenol in apples and strawberries, has a variety of biological activities, including antioxidant, anti-inflammatory, anti-diabetic, and anti-aging activities. We aimed to determine the protective effects and potential mechanisms of PHN in lipopolysaccharide (LPS)-induced acute orchitis in mice. Method: After 21 days of PHN pretreatment, mice were injected with LPS to induce testicular inflammation, and then the changes of testicular tissue structure, expression of inflammatory factors, testosterone level, expression of testosterone-related genes, adhesion gene and protein expression were detected, and the structural changes in the intestinal flora after PHN treatment were further detected by 16SRNA. Result: Our results demonstrated that PHN treatment reduced LPS-induced testicular injury and body and testicular weight losses. The mRNA expression levels of pro-inflammatory cytokines-related genes and antioxidant enzyme activity were also decreased and elevated, respectively, by PHN administration; however, PHN treatment also reduced the LPS-induced decrease in testosterone levels in the testes. Additionally, further studies found that PHN increased the expression of marker proteins zonula occludens-1 (ZO-1) and occludin associated with the blood testosterone barrier compared with that in LPS treatment groups. To further examine the potential mechanisms of the protective effect of PHN on LPS-induced testicular injury, we compared the differences of gut microbiota compositions between the 100 mg/kg PHN treatment group and the control group using 16SRNA. Metagenomic analyses indicated that the abundances of Bacteroidetes, Muribaculaceae, Lactobacillaceae, uncultured bacterium f Muribaculaceae, and Lactobacillus in the PHN treatment group improved, while potential microbes that can induce intestinal diseases, including Verrucomicrobia, Epsilonbacteraeota, Akkermansiaceae, and Akkermansia decreased in the PHN treatment group. Conclusion: Our results indicate that PHN pretreatment might alleviate orchitis by altering the composition of gut microflora, which may provide a reference for reducing the occurrence of acute orchitis in male animals.

PI3K/AKT mediated De novo fatty acid synthesis regulates RIG-1/MDA-5-dependent type I IFN responses in BVDV-infected CD8+T cells.

Bovine viral diarrhea virus (BVDV) has caused massive economic losses in the cattle business worldwide. Fatty acid synthase (FASN), a key enzyme of the fatty acid synthesis (FAS) pathway, has been shown to support virus replication. To investigate the role of fatty acids (FAs) in BVDV infection, we infected CD8+T lymphocytes obtained from healthy cattle with BVDV in vitro. During early cytopathic (CP) and noncytopathic (NCP) BVDV infection in CD8+ T cells, there is an increase in de novo lipid biosynthesis, resulting in elevated levels of free fatty acids (FFAs) and triglycerides (TG). BVDV infection promotes de novo lipid biosynthesis in a dose-dependent manner. Treatment with the FASN inhibitor C75 significantly reduces the phosphorylation of PI3K and AKT in BVDV-infected CD8+ T cells, while inhibition of PI3K with LY294002 decreases FASN expression. Both CP and NCP BVDV strains promote de novo fatty acid synthesis by activating the PI3K/AKT pathway. Further investigation shows that pharmacological inhibitors targeting FASN and PI3K concurrently reduce FFAs, TG levels, and ATP production, effectively inhibiting BVDV replication. Conversely, the in vitro supplementation of oleic acid (OA) to replace fatty acids successfully restored BVDV replication, underscoring the impact of abnormal de novo fatty acid metabolism on BVDV replication. Intriguingly, during BVDV infection of CD8+T cells, the use of FASN inhibitors prompted the production of IFN-α and IFN-ß, as well as the expression of interferon-stimulated genes (ISGs). Moreover, FASN inhibitors induce TBK-1 phosphorylation through the activation of RIG-1 and MDA-5, subsequently activating IRF-3 and ultimately enhancing the IFN-1 response. In conclusion, our study demonstrates that BVDV infection activates the PI3K/AKT pathway to boost de novo fatty acid synthesis, and inhibition of FASN suppresses BVDV replication by activating the RIG-1/MDA-5-dependent IFN response.

Brazilin plays an anti-inflammatory role with regulating Toll-like receptor 2 and TLR 2 downstream pathways in Staphylococcus aureus-induced mastitis in mice.

Mastitis, which commonly occurs during the postpartum period, is caused by the infection of the mammary glands. The most common infectious bacterial pathogen of mastitis is Staphylococcus aureus (S. aureus) in both human and animals. Brazilin, a compound isolated from the traditional herbal medicine Caesalpinia sappan L., has been shown to exhibit multiple biological properties. The present study was performed to determine the effect of brazilin on the inflammatory response in the mouse model of S. aureus mastitis and to confirm the mechanism of action involved. Brazilin treatment was applied in both a mouse model and cells. After brazilin treatment of cells, Western blotting and qPCR were performed to detect the protein levels and mRNA levels, respectively. Brazilin treatment significantly attenuated inflammatory cell infiltration and inhibited the expressions of TNF-α, IL-1ß and IL-6 in a dose-dependent manner. Administration of brazilin in mice suppressed S. aureus-induced inflammatory injury and the production of proinflammatory mediators. This suppression was achieved by reducing the increased expression of TLR2 and regulating the NF-κB and MAPK signaling pathways in the mammary gland tissues and cells with S. aureus-induced mastitis. These results suggest that brazilin appears to be an effective drug for the treatment of mastitis and may be applied as a clinical therapy.

Bergenin Plays an Anti-Inflammatory Role via the Modulation of MAPK and NF-κB Signaling Pathways in a Mouse Model of LPS-Induced Mastitis.

Mastitis is a major disease in humans and other animals and is characterized by mammary gland inflammation. It is a major disease of the dairy industry. Bergenin is an active constituent of the plants of genus Bergenia. Research indicates that bergenin has multiple biological activities, including anti-inflammatory and immunomodulatory properties. The objective of this study was to evaluate the protective effects and mechanism of bergenin on the mammary glands during lipopolysaccharide (LPS)-induced mastitis. In this study, mice were treated with LPS to induce mammary gland mastitis as a model for the disease. Bergenin treatment was initiated after LPS stimulation for 24 h. The results indicated that bergenin attenuated inflammatory cell infiltration and decreased the concentration of NO, TNF-α, IL-1ß, and IL-6, which were increased in LPS-induced mouse mastitis. Furthermore, bergenin downregulated the phosphorylation of nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases (MAPK) signaling pathway proteins in mammary glands with mastitis. In conclusion, bergenin reduced the expression of NO, TNF-α, IL-1ß, and IL-6 proinflammatory cytokines by inhibiting the activation of the NF-κB and MAPKs signaling pathways, and it may represent a novel treatment strategy for mastitis.