Effects of tocilizumab on renal function and oxidative stress in an experimental model of acute ischemic kidney injury*

Abstract

Introduction: Acute kidney injury (AKI) results from renal damage that triggers oxidative stress, inducing apoptosis, structural abnormalities in cells and their organelles, and even mitochondrial DNA instability. Tocilizumab is a monoclonal antibody inhibitor of interleukin-6, initially used to treat rheumatoid arthritis and later tested for COVID-19 treatment, which may have a protective effect on AKI. Objective: To evaluate the effect of tocilizumab on renal function and oxidative profile in rats with ischemic AKI. Methods: This is an experimental study using a quantitative approach with animals. The animals were randomized into four groups: SHAM (control); TCZ (tocilizumab); I/R (ischemia/renal reperfusion, clamping of both renal pedicles for 30 minutes); and TCZ + I/R. Tests were performed to assess renal function (inulin clearance and plasma creatinine), renal oxidation (urinary peroxides, malondialdehyde-derived oxidative substances), and endogenous antioxidant agents (thiols). Results: Regarding renal function, the treated group showed improvement in inulin clearance (IR 0.24 ± 0.3 vs TCZ + IR 0.65 ± 0.05; p < 0.05) and plasma creatinine levels (IR 2.3 ± 0.6 vs TCZ + IR 0.8 ± 0.3; p < 0.05). Analysis of the oxidative profile revealed a reduction in peroxides, confirming an attenuation of the redox mechanism (IR 15.8 ± 2.8 vs. TCZ + IR 3.7 ± 1.3; p < 0.05). Conclusion: Tocilizumab demonstrated renoprotective effects, improving renal function and reducing oxidative stress.