Significance: Dysregulation of the alternative complement pathway due to impaired binding of complement factor H (CFH) to self-ligands or altered self-ligands (e.g. malondialdehyde [MDA]-modified molecules) involved in homeostasis can promote the development of complement-related diseases, such as age-related macular degeneration (AMD). We identified, in an unbiased GWAS approach, that common genetic variants within the CFH gene family (rs1061170 and the deletion of the complement factor H-related protein 1 and 3 genes [CFHR3andCFHR1]) act as major modulators of CFH recruitment and its ability to regulate complement on MDA-epitopes. These findings demonstrate the importance of the genetic status within theCFH/CFHR3/CFHR1locus in tissue homeostasis and provide a mechanistic explanation as to why deletion ofCFHR3/CFHR1is protective in AMD development.

Renalase is a protein secreted in kidneys and considered as a blood pressure modulator. High rates of hypertension and its regulation in patients on hemodialysis demands search for potential cause and treatment. The aim of this study was to determine the genotype and allele frequencies of renalase gene rs2576178 polymorphism in population from Bosnia and Herzegovina. Also, the objective of present study was to find the possible association between renalase gene rs2576178 polymorphism and hypertension in patients on hemodialysis. The genotype of renalase gene rs2576178 polymorphism was determined in 137 participants (100 patients on hemodialysis and 37 controls), using polymerase chain reaction (PCR) and subsequent cleavage with MspI restriction endonuclease. Genotype and allele frequencies were assessed for Hardy-Weinberg equilibrium using a Chi-squared test. The value of P<0.05 was considered as statistically significant. Comparison of genotype distribution and allele frequency in participants on hemodialysis with and without hypertension, and healthy control showed no statistical difference. The results of the study suggest that renalase gene rs2576178 polymorphism is not a factor that influences blood pressure in patients on hemodialysis.

Diabetic nephropathy (DN) is a major microvascular complication of diabetes mellitus and the leading cause of end‐stage renal disease. Oxidative stress and inflammation are central drivers of DN progression, yet no effective therapies exist to prevent or delay renal injury. This study investigated the renoprotective effects of glycine (GLY), N‐acetylcysteine (NAC), and their combination administered at early versus late stages of streptozotocin induced diabetes. Forty‐eight male Wistar rats ( n = 48) were allocated into five groups: healthy controls (Group 1, n = 6), untreated diabetic rats (Group 2, n = 6), and three treatment groups (Groups 3–5, each n = 12). Diabetes was induced by a single intraperitoneal streptozotocin injection (55 mg/kg). Group 3 received NAC (100 mg/kg), Group 4 received GLY (250 mg/kg), and Group 5 received NAC + GLY. Each treatment group was subdivided into early (6 week, n = 6) and late (12 week, n = 6) intervention subgroups. Treatments were administered orally. Renal tissue was evaluated using classic histology, geometric morphometric analysis, and biochemical assays of superoxide dismutase (SOD) and myeloperoxidase (MPO). Statistical analyzes were performed using ANOVA with appropriate post hoc tests ( p < 0.05). Untreated diabetic rats (Group 2) showed significantly decreased SOD activity, increased MPO levels, marked mesangial matrix expansion, glomerular hypercellularity, tubular epithelial degeneration, and interstitial inflammation with fibrosis. NAC (Group 3) and GLY (Group 4) each improved oxidative stress markers and partially restored glomerular and tubular morphology, with early treatment subgroups exhibiting more substantial benefit than late subgroups. The combined NAC + GLY therapy (Group 5) demonstrated the strongest renoprotective effect, preserving renal structure and biochemical parameters closest to healthy controls. To conclude, early combined administration of glycine and N ‐acetylcysteine yields superior protection against diabetes‐induced renal injury compared with individual treatments. These findings support the therapeutic potential of antioxidant‐amino acid combinations in preventing or delaying diabetic nephropathy.

Background/Objectives: Diabetic cardiomyopathy (DCM) is a major cardiovascular complication of diabetes mellitus characterized by progressive myocardial remodeling driven by oxidative stress, inflammation, and fibrosis. The interleukin-33 (IL-33)/soluble suppression of tumorigenicity 2 (sST2) signaling axis has recently emerged as an important regulator of cardiac remodeling and a potential therapeutic target in DCM. N-acetylcysteine (NAC) and glycine exhibit complementary antioxidant and anti-inflammatory properties; however, their combined effects on circulating IL-33 and sST2 levels and myocardial structural remodeling in experimental diabetes remain insufficiently investigated. This study evaluated the effects of NAC and glycine, administered alone or in combination, on oxidative stress, inflammatory biomarkers, cardiac morphology, and serum sST2 levels in streptozotocin-induced diabetic rats. Methods: Thirty-four adult Wistar rats were randomly assigned to five groups: healthy controls, untreated diabetic animals, diabetic animals treated with NAC (100 mg/kg/day), glycine (250 mg/kg/day), or combined NAC and glycine for 12 weeks. Diabetes was induced by a single intraperitoneal injection of streptozotocin (55 mg/kg). Serum concentrations of sST2, IL-33, malondialdehyde (MDA), and superoxide dismutase (SOD) activity were determined. Cardiac remodeling was evaluated by stereological and histopathological analyses. Results: Experimental diabetes significantly increased serum sST2, IL-33, and MDA concentrations and induced marked myocardial remodeling characterized by expansion of the interstitial and perivascular compartments, increased connective tissue deposition, and reduced cardiomyocyte volume density. Both NAC and glycine significantly attenuated these biochemical and structural abnormalities compared with untreated diabetic animals. Treatment effects varied across outcomes. The combined NAC and glycine regimen was associated with particularly pronounced reductions in sST2 and IL-33 and with preservation of myocardial architecture, whereas the magnitude of improvement in oxidative stress markers differed between treatment groups. Conclusions: NAC and glycine, administered either alone or in combination, attenuated several biochemical and structural alterations associated with streptozotocin-induced diabetes. The magnitude of these effects varied across the assessed outcomes, with the combined regimen showing particularly favorable effects on circulating sST2 and IL-33 levels and myocardial structural remodeling, while some oxidative stress parameters showed greater improvement with NAC monotherapy. These outcome-dependent effects highlight the potential complementary actions of NAC and glycine without implying uniform superiority of the combined regimen. Overall, these findings provide an experimental basis for further investigation of NAC- and glycine-based therapeutic approaches for diabetes-associated myocardial remodeling.

Multicellular organisms rely on efficient removal of dying cells to maintain tissue homeostasis. However, during severe tissue damage, when clearance mechanisms are overwhelmed, uncleared dying cells expose various danger-associated molecular patterns (DAMPs), such as malondialdehyde (MDA)- epitopes, which further propagate disease-associated sterile inflammation. MDA-epitopes are present on the surface of dying cells and are specifically recognized by several complement proteins, but the precise nature of their membrane exposure nor whether, and how, this interaction contributes to the removal of dead cells is unknown. Here, we demonstrate that MDA-epitopes were detected on the surfaces of dying cells generated by extrinsic or intrinsic triggers of apoptosis, ferroptosis, and necroptosis, and their occurrence was associated with loss of membrane integrity. Moreover, we show that MDA adducts activate the classical complement pathway by directly binding natural IgM antibodies and C1q and regulate the extent of complement activation through MDA-dependent preferential recruitment of the acute-phase variant of C4b-binding protein (C4BP (α6β0)). This MDA-epitope-guided and C4BP-tuned opsonization of dying cells with IgM, C1q, C4b, and C3b modulates their clearance by phagocytes in human and murine in vitro assays. Our findings identify MDA-epitopes as key mediators in recognizing and clearing dying cells, linking oxidative stress to immune activation and tissue homeostasis.