Sinigrin reduces the virulence of Staphylococcus aureus by targeting coagulase.

Multi-resistant Staphylococcus aureus (S. aureus) infection is a significant global health concern owing to its high mortality and morbidity rates. Coagulase (Coa), a key enzyme that activates prothrombin to initiate host coagulation, has emerged as a promising target for anti-infective therapeutic approaches. This study identified sinigrin as a potent Coa inhibitor that significantly inhibited S. aureus-induced coagulation at concentration as low as 32 mg/L. Additionally, at a higher concentration of 128 mg/L, sinigrin disrupted the self-protection mechanism of S. aureus. Thermal shift and fluorescence-quenching assays confirmed the direct binding of sinigrin to the Coa protein. Molecular docking analysis predicted specific binding sites for sinigrin in the Coa molecule, and point mutation experiments highlighted the importance of Arg-187 and Asp-222 as critical binding sites for both Coa and sinigrin. In vivo studies demonstrated that the combination of sinigrin with oxacillin exhibited greater antibacterial efficacy than oxacillin alone in the treatment of S. aureus-induced pneumonia in mice. Furthermore, sinigrin was shown to reduce bacterial counts and inflammatory cytokine levels in the lung tissues of S. aureus-infected mice. In summary, sinigrin was shown to directly target Coa, resulting in the attenuation of S. aureus virulence, which suggests the potential of sinigrin as an adjuvant for future antimicrobial therapies.

Association between vitamin D receptor gene polymorphisms and susceptibility to tuberculosis: a systematic review and meta-analysis.

Objective: Tuberculosis (TB) is the leading cause of mortality worldwide. Previous studies have reported that TB susceptibility can be caused by vitamin D deficiency, which is affected by polymorphisms in the vitamin D receptor (VDR) gene. However, these results have been inconsistent. Therefore, we performed a meta-analysis to investigate the association between VDR polymorphisms and TB susceptibility. Methods: We systematically searched for relevant literature in PubMed, Embase, and Medline databases through December 31st, 2022. Inclusion and exclusion criteria were made to ensure that HIV-negative population is the targeted subjects. The pooled odds ratio (OR) and 95% confidence interval (CI) were then used to assess the strength of the association, and the quality of the included articles was evaluated using the Newcastle-Ottawa Scale. Potential sources of heterogeneity were evaluated based on subgroup and meta-regression analyses. Results: In our meta-analysis, we found that the FokI polymorphism in the VDR gene was associated with increased TB susceptibility in the allele and recessive genotype models (OR f vs. F = 1.235, 95%CI: 1.035-1.475; OR ff vs. Ff + FF = 1.317, 95%CI: 1.005-1.727. Further subgroup analysis based on ethnicity demonstrated the association with the risk of TB in all genotype models of the FokI polymorphism for Han population. Meta-regression analysis also indicated that ethnicity could be a potential source of heterogeneity in the FokI and BsmI polymorphisms in the VDR gene. However, publication year was another source of heterogeneity for the TaqI polymorphism. Conclusion: In summary, the FokI polymorphism in the VDR gene was found to increase the risk of TB in the HIV-negative population, both overall and in Asian populations. The findings presented in this paper could provide clues for preventing TB from the perspective of vitamin D supplementation, which is a controversial topic in the field of medicine and health.