Puerarin alleviates diabetic nephropathy by inhibiting Caspase-1-mediated pyroptosis.

BACKGROUND AND PURPOSE: Diabetic nephropathy (DN) is an important cause of end-stage renal disease, with podocyte injury as the main feature. Pyroptosis plays a non-negligible role in the process of diabetic nephropathy. Puerarin (PR) treatment of diabetic nephropathy has great potential, but the mechanism is not very clear. This article aims to study the protective effect and mechanism of puerarin on DN. METHODS: Streptozotocin (STZ)-induced C57 BL/6J mouse model of DN was given PR, Necrosulfomide (NSA), Nigericin for 12 weeks; A 60 mM high glucose(HG) induced MPC5 cell injury model was administered to PR, NSA, and Nigericin interventions for 24 h. RESULTS: After 12 weeks of administration, PR reduced fasting blood glucose levels in DN mice, alleviated glomerular lesions, reduced podocyte damage, and protected renal function. Meanwhile, PR also inhibits the expression of pyroptosis-related proteins. In addition, PR alleviated the release of Interleukin 18 (IL-18), Interleukin 1beta (IL-1ß), and lactate dehydrogenase (LDH) in MPC5 cells under HG conditions, downregulated the expression of pyrozozois-related proteins, and improved Caspase-1-mediated pyroptosis in MPC5 cells. CONCLUSION: Our study suggests that the beneficial effects of PR in diabetic nephropathy may be associated with inhibition of Caspase-1-mediated pyroptosis.

Presence of sputum IgG against eosinophilic inflammatory proteins in asthma.

Background: Sputum immunoglobulin G (Sp-IgG) has been discovered to induce cytolytic extracellular trap cell death in eosinophils, suggesting a potential autoimmune mechanism contributing to asthma. This study aimed to explore the potential origin of Sp-IgG and identify clinically relevant subtypes of Sp-IgG that may indicate autoimmune events in asthma. Methods: This study included 165 asthmatic patients and 38 healthy volunteers. We measured Sp-IgG and its five subtypes against eosinophil inflammatory proteins (Sp-IgGEPs), including eosinophil peroxidase, eosinophil major basic protein, eosinophil-derived neurotoxin, eosinophil cationic protein, and Charcot-Leyden Crystal protein in varying asthma severity. Clinical and Mendelian randomization (MR) analyses were conducted. A positive Sp-IgGEPs signature (Sp-IgGEPs+) was defined when any of the five Sp-IgGEPs values exceeded the predefined cutoff thresholds, calculated as the mean values of healthy controls plus twice the standard deviation. Results: The levels of Sp-IgG and Sp-IgGEPs were significantly elevated in moderate/severe asthma than those in mild asthma/healthy groups (all p < 0.05). Sp-IgG levels were positively correlated with airway eosinophil and Sp-IgGEPs. MR analysis showed causality between eosinophil and IgG (OR = 1.02, 95%CI = 1.00-1.04, p = 0.020), and elevated IgG was a risk factor for asthma (OR = 2.05, 95%CI = 1.00-4.17, p = 0.049). Subjects with Sp-IgGEPs+ exhibited worse disease severity and served as an independent risk factor contributing to severe asthma (adjusted-OR = 5.818, adjusted-95% CI = 2.193-15.431, adjusted-p < 0.001). Receiver operating characteristic curve analysis demonstrated that the combination of Sp-IgGEPs+ with non-allergic status, an ACT score < 15, and age ≥ 45 years, effectively predicted severe asthma (AUC = 0.84, sensitivity = 86.20%, specificity = 67.80%). Conclusion: This study identifies a significant association between airway eosinophilic inflammation, Sp-IgG, and asthma severity. The Sp-IgGEPs panel potentially serves as the specific biomarker reflecting airway autoimmune events in asthma.