Accelerated lipid peroxidation in a rat model of gentamicin nephrotoxicity

Preconditioning by Moderate-Intensity Exercise Prevents Gentamicin-Induced Acute Kidney Injury

A strict correlation among proximal tubule epithelial cell dysfunction, proteinuria, and modulation of the Renin-Angiotensin System and Kalikrein-Kinin System are crucial factors in the pathogenesis of Acute Kidney Injury (AKI). In this study, we investigated the potential protective effect of preconditioning by moderate-intensity aerobic exercise on gentamicin-induced AKI. Male Wistar rats were submitted to a moderate-intensity treadmill exercise protocol for 8 weeks, and then injected with 80 mg/kg/day s.c. gentamicin for 5 consecutive days. Four groups were generated: 1) NT+SAL (control); 2) NT+AKI (non-trained with AKI); 3) T+SAL (trained); and 4) T+AKI (trained with AKI). The NT+AKI group presented: 1) impairment in glomerular function parameters; 2) increased fractional excretion of Na + , K + , and water; 4) proteinuria and increased urinary γ-glutamyl transferase activity (a marker of tubular injury) accompanied by acute tubular necrosis; 5) an increased renal angiotensin-converting enzyme and bradykinin B1 receptor mRNA expression. Interestingly, the preconditioning by moderate-intensity aerobic exercise attenuated all alterations observed in gentamicin-induced AKI (T+AKI group). Taken together, our results show that the preconditioning by moderate-intensity aerobic exercise ameliorates the development of gentamicin-induced AKI. Our findings help to expand the current knowledge regarding the effect of physical exercise on kidneys during physiological and pathological conditions.

Curcumin and Vitamin C Attenuate Gentamicin-Induced Nephrotoxicity by Modulating Distinctive Reactive Species

Gentamicin remains widely used in all age groups despite its well-documented nephrotoxicity; however, no adjuvant therapies have been established to counteract this side effect. Our study aimed to experimentally determine whether curcumin and vitamin C have nephroprotective effects and whether certain reactive species could be used as markers of early gentamicin nephrotoxicity. Wistar adult male rats were evenly distributed into four groups: control, gentamicin, curcumin and gentamicin, vitamin C and gentamicin (gentamicin: 60 mg/kg/day, intraperitoneally, 7 days). We determined renal function (urea, creatinine), oxidative stress (malondialdehyde, nitric oxide, 3-nitrotyrosine, total oxidative stress), and antioxidant and anti-inflammatory status (thiols, total antioxidant capacity, interleukin-10). Nephrotoxicity was successfully induced, as shown by the elevated creatinine levels in the gentamicin group. In contrast, supplementation with curcumin and vitamin C prevented an increase in urea levels while decreasing total oxidative stress levels compared to the gentamicin group. Moreover, vitamin C and curcumin distinctively modulate the levels of nitric oxide and malondialdehyde. Histological analysis showed more discrete lesions in rats that received vitamin C compared to the curcumin group.

The Programmed Cell Death of Macrophages, Endothelial Cells, and Tubular Epithelial Cells in Sepsis-AKI

Sepsis is a systemic inflammatory response syndrome caused by infection, following with acute injury to multiple organs. Sepsis-induced acute kidney injury (AKI) is currently recognized as one of the most severe complications related to sepsis. The pathophysiology of sepsis-AKI involves multiple cell types, including macrophages, vascular endothelial cells (ECs) and renal tubular epithelial cells (TECs), etc. More significantly, programmed cell death including apoptosis, necroptosis and pyroptosis could be triggered by sepsis in these types of cells, which enhances AKI progress. Moreover, the cross-talk and connections between these cells and cell death are critical for better understanding the pathophysiological basis of sepsis-AKI. Mitochondria dysfunction and oxidative stress are traditionally considered as the leading triggers of programmed cell death. Recent findings also highlight that autophagy, mitochondria quality control and epigenetic modification, which interact with programmed cell death, participate in the damage process in sepsis-AKI. The insightful understanding of the programmed cell death in sepsis-AKI could facilitate the development of effective treatment, as well as preventive methods.