Protective Effect of Melatonin for Renal Ischemia-Reperfusion Injury: A Systematic Review and Meta-Analysis

Background: Renal ischemia-reperfusion (I/R) injury is one of the major causes related to acute kidney damage. Melatonin has been shown as a powerful antioxidant, with many animal experiments have been designed to evaluate the therapeutic effect of it to renal I/R injury.Objectives: This systematic review aimed to assess the therapeutic effect of melatonin for renal I/R injury in animal models.Methods and Results: The PubMed, Web of Science, Embase, and Science Direct were searched for animal experiments applying melatonin to treat renal I/R injury to February 2021. Thirty-one studies were included. The pooled analysis showed a greater reduction of blood urea nitrogen (BUN) (21 studies, weighted mean difference (WMD) = −30.00 [−42.09 to −17.91], p < 0.00001), and serum creatinine (SCr) (20 studies, WMD = −0.91 [−1.17 to −0.66], p < 0.00001) treated with melatonin. Subgroup analysis suggested that multiple administration could reduce the BUN compared with control. Malondialdehyde and myeloperoxidase were significantly reduced, meanwhile, melatonin significantly improved the activity of glutathione, as well as superoxide dismutase. The possible mechanism for melatonin to treat renal I/R injury is inhibiting endoplasmic reticulum stress, apoptosis, inflammation, autophagy, and fibrillation in AKI to chronic kidney disease.Conclusions: From the available data of small animal studies, this systematic review demonstrated that melatonin could improve renal function and antioxidative effects to cure renal I/R injury through, then multiple administration of melatonin might be more appropriate. Nonetheless, extensive basic experiments are need to study the mechanism of melatonin, then well-designed randomized controlled trials to explore the protective effect of melatonin.

miR-3587 Inhibitor Attenuates Ferroptosis Following Renal Ischemia-Reperfusion Through HO-1

Renal ischemia-reperfusion (IR) is frequently observed in patients who are critically ill, yet there are no reliable or effective approaches for the treatment of this condition. Ferroptosis, a form of programmed cell death, is regulated by key genes such as glutathione peroxidase 4 (GPX4) and heme oxygenase-1 (HMOX1) and participates in the injury of renal tubular epithelial cells during IR. This study aimed to investigate the miRNA-mRNA regulatory networks involved in ferroptosis following renal IR. Using bioinformatics analysis, HMOX1 was found to be significantly upregulated during the early stages of renal IR injury, and microRNA-3587 (miR-3587) was identified as a putative regulator of HMOX1. When a miR-3587 inhibitor was applied in a hypoxia-reoxygenation (HR) model system using renal tubular epithelial cells, HO-1 protein (encoded by HMOX1) expression was significantly increased relative to that observed in the HR group, with concomitant increases in GPX4 protein levels, enhanced cell viability, a reduction in malondialdehyde content, decreased Fe2+ level, and the restoration of normal mitochondrial membrane potential. Transmission electron microscopy showed a reduced or absent mitochondrial crest and a damaged mitochondrial outer membrane. Targeting of HMOX1 by miR-3587 was confirmed by luciferase reporter gene assay. In conclusion, these preliminary results indicate that inhibition of miR-3587 promotes HO-1 upregulation, thereby protecting renal tissues from IR-induced ferroptosis.

IL-37 expression improves renal function after ischemia and reperfusion in mice model

Renal ischemia is a major problem in the world that lead to renal failure for which no effective treatment is available. Renal ischemia involves a robust inflammatory response, involving up-regulated chemokine expression and leukocyte accumulation, contributes to the mechanism of renal injury and renal failure. IL-37 is a new human cytokine and has an anti-inflammatory function. Currently, it is unknown whether IL-37 suppresses renal inflammatory response to ischemia. We tested the hypothesis that expression of human IL-37 in mouse protects the renal against ischemic injury through suppression of the renal inflammatory response. IL-37 Tg and WT mice were subjected to right renal nephrectomy to induce unilateral model of ischemia the microvascular clamp was positioned around the left renal pedicles. Serum sampling for measurements of TNF-α, IL-1β, Caspase3, MDA, HMGB1, urea and creatinine. Hematoxylin-eosin staining for histological analysis. The resulted data showed that IL-37 has anti-inflammatory effects in renal IRI as evidenced by significant reduction of the inflammatory markers levels TNF-α, IL-1β and HMGB1. IL-37 has potent antioxidant and anti-apoptotic effects with significant reduction in MDA and caspace-3 respectively

IL-37 expression improves renal function after ischemia and reperfusion in mice model

Renal ischemia is a major problem in the world that lead to renal failure for which no effective treatment is available. Renal ischemia involves a robust inflammatory response, involving up-regulated chemokine expression and leukocyte accumulation, contributes to the mechanism of renal injury and renal failure. IL-37 is a new human cytokine and has an anti-inflammatory function. Currently, it is unknown whether IL-37 suppresses renal inflammatory response to ischemia. We tested the hypothesis that expression of human IL-37 in mouse protects the renal against ischemic injury through suppression of the renal inflammatory response. IL-37 Tg and WT mice were subjected to right renal nephrectomy to induce unilateral model of ischemia the microvascular clamp was positioned around the left renal pedicles. Serum sampling for measurements of TNF-α, IL-1β, Caspase3, MDA, HMGB1, urea and creatinine. Hematoxylin-eosin staining for histological analysis. The resulted data showed that IL-37 has anti-inflammatory effects in renal IRI as evidenced by significant reduction of the inflammatory markers levels TNF-α, IL-1β and HMGB1. IL-37 has potent antioxidant and anti-apoptotic effects with significant reduction in MDA and caspace-3 respectively. Keywords: Renal ischemia, IL-37, TNF-α, IL-1β, Caspase-3

IL-37 expression improves renal function after ischemia and reperfusion in mice model

Renal ischemia is a major problem in the world that lead to renal failure for which no effective treatment is available. Renal ischemia involves a robust inflammatory response, involving up-regulated chemokine expression and leukocyte accumulation, contributes to the mechanism of renal injury and renal failure. IL-37 is a new human cytokine and has an anti-inflammatory function. Currently, it is unknown whether IL-37 suppresses renal inflammatory response to ischemia. We tested the hypothesis that expression of human IL-37 in mouse protects the renal against ischemic injury through suppression of the renal inflammatory response. IL-37 Tg and WT mice were subjected to right renal nephrectomy to induce unilateral model of ischemia the microvascular clamp was positioned around the left renal pedicles. Serum sampling for measurements of TNF-α, IL-1β, Caspase3, MDA, HMGB1, urea and creatinine. Hematoxylin-eosin staining for histological analysis. The resulted data showed that IL-37 has anti-inflammatory effects in renal IRI as evidenced by significant reduction of the inflammatory markers levels TNF-α, IL-1β and HMGB1. IL-37 has potent antioxidant and anti-apoptotic effects with significant reduction in MDA and caspace-3 respectively.