Association of TGF-β1, IL-4, and IL-10 Polymorphisms With Chronic Kidney Disease Susceptibility: A Meta-Analysis

Naringenin suppresses aluminum-induced experimental hepato-nephrotoxicity in mice through modulation of oxidative stress and inflammation

Aluminum is a widely used metal substance in daily life activities that has been shown to cause severe hepato-nephrotoxicity with long-term exposure. Natural dietary flavonoids are being utilized as a newer pharmaceutical approach against various acute and chronic diseases. Naringenin (NAR) has shown efficient therapeutic properties, including effects against metal toxicities. However, the protective efficacy of NAR on aluminum chloride (AlCl3)-induced hepato-renal toxicity needs investigation as aluminum has shown serious environmental toxicity and bioaccumulation behavior. In this study, mice were treated with AlCl3 (10 mg/kg b.w./day) to assess toxicities, and a group of mice were co-treated with NAR (10 mg/kg b.w./day) to assess the protective effects of NAR against hepato-nephrotoxicity. The levels of blood serum enzymes, oxidative stress biomarkers, inflammatory cytokines, and the apoptosis marker caspase-3 were measured using histological examinations. NAR treatment in AlCl3-treated mice resulted in maintained levels of liver and kidney function enzymes and lipid profiles. NAR treatment attenuated oxidative stress by regulating the levels of nitric oxide, advance oxidation of protein products, protein carbonylation, and lipid peroxidation. NAR also replenished reduced antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and reduced the levels of glutathione and oxidized glutathione. NAR regulated the levels of pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) and elevated the levels of anti-inflammatory cytokines (IL-4, IL-10, and IFN-γ). The histological study further confirmed the protective effects of NAR against AlCl3-induced hepato-renal alterations. NAR decreased the expression of caspase-3 as a mechanism of protective effects against apoptotic damage in the liver and kidney of AlCl3-treated mice. In summary, this study demonstrated the antioxidant and anti-inflammatory properties of NAR, leading to the suppression of AlCl3-triggered hepato-renal apoptosis and histological alterations. The results suggest that aluminum toxicity needs to be monitored in daily life usage, and supplementation of the natural dietary flavonoid naringenin may help maintain liver and kidney health.

Investigation of the Relationship Between IL-18 (- 607 C/A), IL-18 (- 137 G/C), and MMP-2 (- 1306 C/T) Gene Variations and Serum Copper and Zinc Levels in Patients Diagnosed with Chronic Renal Failure

The aim of this study is to investigate the relationship between IL-18 (- 607 C/A), IL-18 (- 137 G/C), and MMP-2 (- 1306 C/T) gene variations and serum trace element levels in patients diagnosed with CRF. Genotype distributions of IL-18 (- 607 C/A, - 137 G/C) gene variations were determined by polymerase chain reaction (PCR) method. PCR-restriction fragment length polymorphism (RFLP) methods were used to determine the MMP-2 (- 1306 C/T) gene variation genotype distributions. Serum trace element levels were determined by atomic absorption spectrophotometer method. A significant difference was found between the CRF patient and healthy control groups in terms of genotype distributions of IL-18 (- 607 C/A) and MMP-2 (- 1306 C/T) gene variations (p < 0.05). The significant difference was found between the patient and control groups in terms of serum copper and zinc levels and copper/zinc ratio (p < 0.05). The significant difference was detected between patient and control groups in terms of copper and zinc levels and copper/zinc ratio according to IL-18 (- 607 C/A), IL-18 (- 137 G/C), and MMP-2 (- 1306 C/T) gene variations and genotype distributions (p < 0.05). In addition, significant difference was determined in terms of serum copper and zinc levels and copper/zinc ratio according to haplotypes of IL-18 (- 607 C/A), IL-18 (- 137 G/C), and MMP-2 (- 1306 C/T) gene variations between patient and control groups (p < 0.05). In conclusion, evaluation of IL-18 (- 607 C/A, - 137 G/C) and MMP-2 (- 1306 C/T) gene variations and serum trace element levels together is extremely important in terms of obtaining important biomarkers in CRF early diagnosis and progression.

Role of eNOS and TGFβ1 gene polymorphisms in the development of diabetic nephropathy in type 2 diabetic patients in South Indian population

Background

Diabetic nephropathy is known to be a leading complication of diabetes mellitus, characterized by diverse aspects such as high urinary albumin level, elevated blood pressure, and genetic susceptibility leading to end-stage renal disease. The current study was carried out to investigate the association of eNOS and TGFβ1 gene polymorphisms in the progression of diabetic nephropathy among type 2 diabetic patients in the South Indian population. The eNOS and TGFβ1 genetic variants were genotyped in 280 T2DM patients, 140 with DN, 140 without DN, and 140 controls. Genotyping was performed using ARMS PCR and the genomic variants were confirmed by the Sanger sequencing method.

Results

A significant (p < 0.05) association was observed in the genotypic frequencies of eNOS (G > T) polymorphism in the T2DM patients with diabetic nephropathy when compared to controls. The frequency of TT (heterozygous) genotype was observed to increase in patients with type 2 diabetes and DN when compared to the diabetic patients without DN and controls. This indicates that diabetic patients with TT genotype are at an increased risk to develop DN. However, TGFβ1 (G > C) polymorphism did not show any association in the allele and genotypic frequencies with DN when compared with T2DM and controls.

Conclusion

The results of the study propose a strong influence of TT genotype of eNOS gene be significantly linked with diabetic nephropathy in T2DM patients. Whereas no association was examined concerning TGFβ1 gene polymorphism and DN. Nevertheless, large sample size studies are required to confirm the part of these genetic variants in the development of DN.

Cytokines and chemokines systemic levels are related to dialysis adequacy and creatinine clearance in patients with end-stage renal disease undergoing hemodialysis

Although the clearance of low-molecular weight toxins is modulated by dialysis dose, the relationship between dialysis adequacy and middle systemic inflammatory mediators is often overlooked. Thus, the relationship between dialysis adequacy, pro- and anti-inflammatory cytokines and chemokines in hemodialysis (HD) patients was investigated. Forty-eight HD patients (19 women and 25 men) were investigated. Age, body mass index, time in HD, nutritional status, Kt/V and blood biochemical parameters was similar in patients of both sexes (P > 0.05). Thus, patients were stratified by dialysis adequacy measured by Kt/V method (adequate Kt/V ≥ 1.2). Post-HD urea, creatinine, cytokines (IFN-γ, IL-4 and IL-10) and chemokines (CCL-2, CCL-5, CXCL-8 and CXCL-10) were higher in patients with Kt/V < 1.2 (P < 0.05). Kt/V exhibited significant correlation with CXCL-10/IP-10 serum levels. Positive correlation between creatinine with IFN-γ, CCL-2/MCP-1, and CXCL-10/IP-10, and negative correlation with IL-10 was identified in patients with Kt/V < 1.2 (P < 0.05). In patients with Kt/V ≥ 1.2, only IL-10 was positively and CXCL-10/IP-10 negatively correlated with creatinine levels (P < 0.05). Kt/V and creatinine levels exhibited variable predictive value (Kt/V = 27% to 37%, creatinine = 29% to 47%) to explain cytokines and chemokines circulating levels in patients with adequate and inadequate dialysis dose. Taken together, our findings provide evidence that in addition to modulating uremic toxins levels, such as urea and creatinine, dialysis dose is associated with circulating levels of inflammatory mediators. Thus, low Kt/V results and creatinine accumulation are potential indicators of the systemic inflammatory stress determined by up-regulation of proinflammatory cytokines and chemokines, and downregulation of anti-inflammatory cytokines.

Long-term exposure to environmental level of phenanthrene causes adaptive immune response and fibrosis in mouse kidneys

As ubiquitous, persistent organic pollutants, polycyclic aromatic hydrocarbons (PAHs) have adverse impacts on human health. Phenanthrene (Phe) is one of the most abundant PAHs in the environment. However, the long-term effects of exposure to environmental level of Phe on the kidneys and the potential mechanisms are unclear. T helper (Th) cells, a subtype of CD4⁺ T cells that play a central role in the renal immune microenvironment. In this study, male mice were chronically exposed to 5, 50, and 500 ng/kg bw Phe every other day for total 210 days. Those results indicated that environmental Phe exposure caused kidney hypertrophy, injury and fibrosis in the mice. Chronic, long-term environmental level of Phe exposure did not significantly alter the innate immune response but induced adaptive immune response changes (Th1/Th2 related cytokines release), causing a type 1 immune response in the 5 ng/kg bw Phe group and a type 2 immune response in the high dose groups (50 and 500 ng/kg bw). This study provides novel insights into the roles of adaptive immune response in long-term PAH exposure-induced chronic kidney injury and fibrosis, which is beneficial for further understanding the potential health hazards of PAHs and providing new avenues for immune intervention strategies to alleviate PAHs toxicity.