Hemolysin Co-Regulatory Protein 1 Enhances the Virulence of Clinically Isolated Escherichia coli in KM Mice by Increasing Inflammation and Inducing Pyroptosis

Hepatoprotective effect of diammonium glycyrrhizinate and neuroprotective effect of piperazine ferulate on AmB-induced liver and kidney injury by suppressing apoptosis in vitro and in vivo

Amphotericin B (AmB) induced liver and kidney injury is often responsible for hepatic and renal dysfunction. Therefore, the protection strategy on liver and renal functions in patients treated with AmB should be emphasized. In this paper, diammonium glycyrrhizinate (DG) and piperazine ferulate (PF) were taken as the research object to study its hepatoprotective and neuroprotective effect on AmB-induced liver and kidney damage in vitro and in vivo. The microplate method and ELISA kits were employed for the biochemical detection in the serum and urine of mice. Flow cytometric analysis and western blotting analysis were conducted to study the mechanism of DG and PF. Our results confirmed the prevention capacity of DG and PF on AmB-induced liver and kidney injury through the alleviation of pathological changes and enzyme reducing action. Furthermore, DG and PF suppressed ROS-mediated mitochondrial apoptosis in AmB-treated mice and cells through Caspase pathway and Caspase-independent AIF pathway. In summary, DG and PF could protect AmB-induced hepatotoxicity and nephrotoxicity by disrupting oxidative stress and apoptosis.

Pyroptosis: The Determinator of Cell Death and Fate in Acute Kidney Injury

Background

Acute kidney injury (AKI) is kidney damage that leads to a rapid decline in function. AKI primarily occurs when the tubular epithelium is damaged, causing swelling, loss of brush margin, and eventual apoptosis. Research has shown that tubular epithelial cell damage in AKI is linked to cell cycle arrest, autophagy, and regulation of cell death.

Summary

Pyroptosis, a type of programmed cell death triggered by inflammation, is believed to play a role in the pathophysiology of AKI. Cumulative evidence has shown that pyroptosis is the main cause of tubular cell death in AKI. Thus, targeted intervention of pyroptosis may be a promising therapeutic approach for AKI. This review delves deep into the cutting-edge research surrounding pyroptosis in the context of AKI, shedding light on its intricate mechanisms and potential implications for clinical practice. Additionally, we explore the exciting realm of potential preclinical treatment options for AKI, aiming to pave the way for future therapeutic advancements.

Key Messages

Pyroptosis, a highly regulated form of cell death, plays a crucial role in determining the fate of cells during the development of AKI. This intricate process involves the activation of inflammasomes, which are multi-protein complexes that initiate pyroptotic cell death. By understanding the mechanisms underlying pyroptosis, researchers aim to gain insights into the pathogenesis of AKI and potentially identify new therapeutic targets for this condition.

Anti-Hcp1 Monoclonal Antibody Is Protective against Burkholderia pseudomallei Infection via Recognizing Amino Acids at Asp95-Leu114

Melioidosis, a severe tropical illness caused by Burkholderia pseudomallei, poses significant treatment challenges due to limited therapeutic options and the absence of effective vaccines. The pathogen's intrinsic resistance to numerous antibiotics and propensity to induce sepsis during acute infections further complicate management strategies. Thus, exploring alternative methods for prevention and treatment is crucial. Monoclonal antibodies (mAbs) have emerged as a promising strategy for the prevention and treatment of infectious diseases. This study focused on generating three mAbs (13F1, 14G11, and 15D9) targeting hemolysin-coregulated protein 1 (Hcp1), a protein involved in the type VI secretion system cluster 1 (T6SS1) of B. pseudomallei. Notably, pretreatment with 13F1 mAb significantly reduced the intracellular survival of B. pseudomallei and inhibited the formation of macrophage-derived multinucleated giant cells (MNGCs). This protective effect was also observed in vivo. We identified a sequence of amino acids (Asp95-Leu114) within Hcp1 as the likely binding site for 13F1 mAb. In summary, our findings reveal that 13F1 mAb counteracts infection by targeting Hcp1, offering potential new targets and insights for melioidosis prevention.

Berberine: An inspiring resource for the treatment of colorectal diseases

Colorectal cancer is a prevalent malignant tumor with a complex and diverse pathogenesis. In recent years, natural products have shown promising application prospects as sources of anticancer drugs. BBR, a class of benzoquinoline alkaloids extracted from various plants, is widely used in disease treatments owing to its pharmacological activities, including antibacterial, anti-inflammatory, antioxidant, anticancer, and anti-angiogenesis properties. Research has demonstrated that BBR exerts an anti-Salmonella and -Escherichia coli infection effect, attenuating inflammatory reactions by inhibiting harmful bacteria. During the stage of colorectal precancerous lesions, BBR inhibits the activity of cell cyclin by regulating the PI3K/AKT, MAPK, and Wnt signaling pathways, thereby decelerating the cell cycle progression of polyp or adenoma cells. Moreover, the inhibitory effect of BBR on colorectal cancer primarily occurs through the regulation of the cancer cell cycle, anti-angiogenesis, gut microbiota, and antioxidant pathways. The specific involved pathways include the MPK/ERK, NF-kB, and EGFR signaling pathways, encompassing the regulation of Bcl-2 family proteins, vascular endothelial growth factor, and superoxide dismutase. This study reviews and summarizes, for the first time, the specific mechanisms of action of BBR in the carcinogenesis process of colorectal cancer, providing novel insights for its clinical application in intestinal diseases.

Yersiniabactin-Producing E. coli Induces the Pyroptosis of Intestinal Epithelial Cells via the NLRP3 Pathway and Promotes Gut Inflammation

The high-pathogenicity island (HPI) was initially identified in Yersinia and can be horizontally transferred to Escherichia coli to produce yersiniabactin (Ybt), which enhances the pathogenicity of E. coli by competing with the host for Fe3+. Pyroptosis is gasdermin-induced necrotic cell death. It involves the permeabilization of the cell membrane and is accompanied by an inflammatory response. It is still unclear whether Ybt HPI can cause intestinal epithelial cells to undergo pyroptosis and contribute to gut inflammation during E. coli infection. In this study, we infected intestinal epithelial cells of mice with E. coli ZB-1 and the Ybt-deficient strain ZB-1Δirp2. Our findings demonstrate that Ybt-producing E. coli is more toxic and exacerbates gut inflammation during systemic infection. Mechanistically, our results suggest the involvement of the NLRP3/caspase-1/GSDMD pathway in E. coli infection. Ybt promotes the assembly and activation of the NLRP3 inflammasome, leading to GSDMD cleavage into GSDMD-N and promoting the pyroptosis of intestinal epithelial cells, ultimately aggravating gut inflammation. Notably, NLRP3 knockdown alleviated these phenomena, and the binding of free Ybt to NLRP3 may be the trigger. Overall, our results show that Ybt HPI enhances the pathogenicity of E. coli and induces pyroptosis via the NLRP3 pathway, which is a new mechanism through which E. coli promotes gut inflammation. Furthermore, we screened drugs targeting NLRP3 from an existing drug library, providing a list of potential drug candidates for the treatment of gut injury caused by E. coli.