Nanosystems for oxidative stress regulation in the anti-inflammatory therapy of acute kidney injury

Nephroprotective effect of diosmin against sodium arsenite-induced renal toxicity is mediated via attenuation of oxidative stress and inflammation in mice

Arsenic compounds, which are used in different industries like pesticide manufacturing, cause severe toxic effects in almost all organs, including the kidneys. Since the primary route of exposure to arsenic is through drinking water, and millions of people worldwide are exposed to unsafe levels of arsenic that can pose a threat to their health, this research was performed to investigate the nephroprotective effects of Diosmin (Dios), a flavonoid found in citrus fruits, against nephrotoxicity induced by sodium arsenite (SA). To induce nephrotoxicity, SA (10 mg/kg, oral gavage) was administered to mice for 30 days. Dios (25, 50, and 100 mg/kg, oral gavage) was given to mice for 30 days prior to SA administration. After the study was completed, animals were euthanized and blood and kidney samples were taken for biochemical and histopathological assessments. Results showed that SA-treated mice significantly increased the blood urea nitrogen and creatinine levels in the serum. This increase was associated with significant kidney tissue damage in SA-treated mice, which was confirmed by histopathological studies. Furthermore, SA enhanced the amounts of renal thiobarbituric acid reactive substances and decreased total thiol reserves, as well as the activity of antioxidant enzymes such as catalase, superoxide dismutase, and glutathione peroxidase. Also, in the SA-exposed group, an increase in the levels of kidney inflammatory biomarkers, including nitric oxide and tumor necrosis factor-alpha was observed. The western blot analysis indicated an elevation in the protein expression of kidney injury molecule-1 and nuclear factor-kappa B in SA-treated mice. However, pretreatment with Dios ameliorated the SA-related renal damage in mice. Our findings suggest that Dios can protect the kidneys against the nephrotoxic effects of SA by its antioxidant and anti-inflammatory characteristics.

Effects of melatonin against acute kidney injury: A systematic review and meta-analysis

INTRODUCTION

Melatonin is a hormone synthesized by the pineal gland, and has antioxidative effects in reducing acute kidney injury (AKI). In the past three years, an increasing number of studies have evaluated whether melatonin has a protective effect on AKI. The study systematically reviewed and assessed the efficacy and safety of melatonin in preventing AKI.

MATERIAL AND METHODS

A systematic literature search was conducted in the PubMed, Embase, and Web of Science databases on February 15, 2023. Eligible records were screened according to the inclusion and exclusion criteria. The odds ratio and Hedges' gwith the corresponding 95% confidence intervals were selected to evaluate the effects of melatonin on AKI. We pooled extracted data using a fixed- or random-effects model based on a heterogeneity test.

RESULTS

There were five studies (one cohort study and four randomized controlled trials) included in the meta-analysis. Although the glomerular filtration rate (GFR) may be significantly improved by melatonin, the incidence of AKI was not significantly decreased in the melatonin group compared with the control group in randomized controlled trials (RCTs).

CONCLUSIONS

In our study, the present results do not support a direct effect of melatonin use on the reduction of AKI. More well-designed clinical studies with larger sample size are required in the future.

Renal-Protective Roles of Lipoic Acid in Kidney Disease

The kidney is a crucial organ that eliminates metabolic waste and reabsorbs nutritious elements. It also participates in the regulation of blood pressure, maintenance of electrolyte balance and blood pH homeostasis, as well as erythropoiesis and vitamin D maturation. Due to such a heavy workload, the kidney is an energy-demanding organ and is constantly exposed to endogenous and exogenous insults, leading to the development of either acute kidney injury (AKI) or chronic kidney disease (CKD). Nevertheless, there are no therapeutic managements to treat AKI or CKD effectively. Therefore, novel therapeutic approaches for fighting kidney injury are urgently needed. This review article discusses the role of α-lipoic acid (ALA) in preventing and treating kidney diseases. We focus on various animal models of kidney injury by which the underlying renoprotective mechanisms of ALA have been unraveled. The animal models covered include diabetic nephropathy, sepsis-induced kidney injury, renal ischemic injury, unilateral ureteral obstruction, and kidney injuries induced by folic acid and metals such as cisplatin, cadmium, and iron. We highlight the common mechanisms of ALA’s renal protective actions that include decreasing oxidative damage, increasing antioxidant capacities, counteracting inflammation, mitigating renal fibrosis, and attenuating nephron cell death. It is by these mechanisms that ALA achieves its biological function of alleviating kidney injury and improving kidney function. Nevertheless, we also point out that more comprehensive, preclinical, and clinical studies will be needed to make ALA a better therapeutic agent for targeting kidney disorders.