Proteomic analysis of ITPR2 as a new therapeutic target for curcumin protection against AFB1-induced pyroptosis.

Aflatoxin B1 (AFB1) is extremely carcinogenic and can cause liver cancer in humans and animals with continued ingestion. As a natural compound, curcumin (Cur) exhibits excellent anti-inflammatory, and anti-cancer properties with few side effects. In this study, a total of 60 male mice (6-week-olds, 15 per group). After one week of acclimatization feeding, the mice were divided into control group (Con), AFB1 group, curcumin group (Cur), and AF+Cur group. The mice were gavaged with curcumin (Cur, 100 mg/kg) and/or AFB1 (0.75 mg/kg). To identify a new therapeutic target for AFB1-induced pyroptosis, we performed proteomic profiling for curcumin alleviating liver injury caused by AFB1 to further validate the targets through volcano plot analysis, Venn analysis, heatmap analysis, correlation, cluster analysis, GO and KEGG enrichment. AFB1 exposure resulted in the loss of hepatocyte membrane, swelling of the endoplasmic reticulum, and a significant increase in transaminase (ALT and AST) contents, while curcumin greatly improved these changes. We found that differentially expressed proteins are enriched in the endoplasmic reticulum membrane and identified ITPR2 as a target of curcumin that alleviates AFB1-induced liver injury by proteomics. Furthermore, ITPR2 expression was detected by immunofluorescence, and qRT-PCR for mRNA expression of genes downstream of ITPR2 (calpain1, calpain2, caspase-12, caspase-3). ITPR2-activated endoplasmic reticulum stress-related proteins (calpain1, calpaini2, bcl-2, BAX, cl-caspase-12, cl-caspase-3), apoptosis (PARP) and pyroptosis (DFNA5) related proteins were examined by western blotting. The analysis showed that it effectively prevents AFB1-induced pyroptosis by lowering endoplasmic reticulum stress via interfering with ITPR2 and its downstream proteins (calpain1, calpain2, bcl-2, Bax) and inhibiting caspase-12/caspase-3 pathway. Conclusively, this study applied proteomic profiling to elucidate ITPR2 as a new target, which might give a new perspective on the mechanism of curcumin alleviating AFB1-induced pyroptosis.

Effect of Curcumin as Feed Supplement on Immune Response and Pathological Changes of Broilers Exposed to Aflatoxin B1.

In this study, we examined the protective effects of curcumin against the AFB1-induced immune response of and pathological changes in broilers. Histopathology examinations showed that at day 28, AFB1 (5 mg/kg) exposure leads to severe histological changes in the spleen, thymus and bursa of Fabricius with a decrease in the number and karyoplasmic area ratio of plasma cells. Curcumin alleviated the AFB1-induced immune organs' damage as well as the changes in plasma cells in a dose-dependent manner. RT-PCR data showed that AFB1 significantly downregulated the IL-2 and IFN-γ mRNA expression levels in the thymus, spleen and bursa of Fabricius. However, curcumin supplementation improved the AFB1-induced immune organs' damage via upregulated cytokines' expression. Intriguingly, similar trends were noticed in abnormal morphological changes and the immune response at day 35 after the withdrawal of AFB1 and curcumin from the diet, suggesting the protective effects and immunomodulatory function against AFB1 in broilers. The current study provides a scientific experimental basis for the application of curcumin as a therapeutic drug or additive in animal husbandry productive practice.

Polydatin mediates Parkin-dependent mitophagy and protects against mitochondria-dependent apoptosis in acute respiratory distress syndrome.

Mitophagy removes dysfunctional mitochondria and is known to play an important role in the pathogenesis of several diseases; however, the role of mitophagy in acute respiratory distress syndrome (ARDS) remains poorly understood. While we have previously demonstrated that polydatin (PD) improves lipopolysaccharide (LPS)-induced ARDS, the specific mechanism remains unclear. In present study, we aimed to determine whether PD activates Parkin-dependent mitophagy to protect against LPS-induced mitochondria-dependent apoptosis and lung injury. To establish the ARDS model, C57BL/6 mice were intratracheally injected with LPS (5 mg/kg) in vivo and Beas-2B cells were exposured to 0.5 mM LPS in vitro. Our results indicate that PD facilitates Parkin translocation to mitochondria and promotes mitophagy in ARDS-challenged mice and LPS-treated Beas-2B cells. However, PD-induced mitophagy was suppressed in Parkin-/- mice and Parkin siRNA transfected cells, indicating that PD activates Parkin-dependent mitophagy. Furthermore, the protective effects of PD against LPS-induced mitochondria-dependent apoptosis and lung injury were suppressed when Parkin was depleted both in vivo and in vitro. The inhibition of mitophagy with mitophagy inhibitor mitochondrial division inhibitor-1 in vivo and silencing of autophagy-related gene 7 in vitro also blocked the protective effects mediated by PD. Our data suggest that Parkin-dependent mitophagy induced by PD provides protection against mitochondria-dependent apoptosis in ARDS.

Susceptibility breakpoint for Danofloxacin against swine Escherichia coli.

BACKGROUND: Improper use of antimicrobials results in poor treatment and severe bacterial resistance. Breakpoints are routinely used in the clinical laboratory setting to guide clinical decision making. Therefore, the objective of this study was to establish antimicrobial susceptibility breakpoints for danofloxacin against Escherichia coli (E.coli), which is an important pathogen of digestive tract infections. RESULTS: The minimum inhibitory concentrations (MICs) of 1233 E. coli isolates were determined by the microdilution broth method in accordance with the guidelines in Clinical and Laboratory Standards Institute (CLSI) document M07-A9. The wild type (WT) distribution or epidemiologic cutoff value (ECV) was set at 8 µg/mL with statistical analysis. Plasma drug concentration data were used to establish pharmacokinetic (PK) model in swine. The in vitro time kill test in our study demonstrated that danofloxacin have concentration dependent activity against E.coli. The PK data indicated that danofloxacin concentration in plasma was rapidly increased to peak levels at 0.97 h and remained detectable until 48 h after drug administration. The pharmacodynamic cutoff (COPD) was determined as 0.03 µg/mL using Monte Carlo simulation. To the best of our knowledge, this is the first study to establish the ECV and COPD of danofloxacin against E.coli with statistical method. CONCLUSIONS: Compared to the COPD of danofloxacin against E.coli (0.03 µg/mL), the ECV for E.coli seemed reasonable to be used as the final breakpoint of danofloxacin against E.coli in pigs. Therefore, the ECV (MIC ≤8 µg/mL) was finally selected as the optimum danofloxacin susceptibility breakpoint for swine E.coli. In summary, this study provides a criterion for susceptibility testing and improves prudent use of danofloxacin for protecting public health.