Protective effects of Urtica dioica L. oil on oxidative stress and inflammation in the rat brain following gamma irradiation and hexavalent chromium exposure

Aim. To evaluate the neuroprotective effects of Urtica dioica L. oil on oxidative stress and inflammatory responses in the brains of rats exposed to ionizing radiation alone or in combination with hexavalent chromium.

Materials and methods. Sixty-five white adult male rats were randomly assigned to five groups (n=13/ group): control, irradiation, irradiation + Urtica dioica L. oil, irradiation + Cr(VI), and irradiation + Cr(VI) + Urtica dioica L. oil. Seven days after irradiation, brain tissue was collected for biochemical analysis. Levels of malondialdehyde (MDA), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were determined.

Results and discussion. Exposure to ionizing radiation, particularly in combination with Cr(VI), significantly impaired antioxidant defenses and increased lipid peroxidation and inflammatory cytokine levels in brain tissue. Pretreatment with Urtica dioica L. oil significantly increased SOD, CAT, and GSH levels while reducing MDA, TNF-α, and IL-6 compared with the corresponding untreated exposed groups (p<0.05).

Conclusions. Urtica dioica L. oil attenuated oxidative stress and neuroinflammation induced by ionizing radiation alone or combined with hexavalent chromium. These findings suggest that nettle oil has promising neuroprotective potential through enhancement of endogenous antioxidant defenses and suppression of inflammatory responses.

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