Protective effect of Thymus munbyanus aqueous extract against 2,4-dichlorophenoxyacetic acid-induced nephrotoxicity in Wistar rats

The aim of the present study was to examine the possible protective effects of the aqueous extract of Thymus munbyanus (TMAE) against 2,4-dichlorophenoxyacetic acid (2,4-D)-induced oxidative stress and renal injury in the kidney of male albino rats. Furthermore, TMAE was assessed to determine the phenolic content. In vitro, antioxidant activities were evaluated by DPPH radical scavenging, inhibition of β-carotene bleaching, and reducing power. The results showed that TMAE contained high amounts of phenolics, flavonoids, and tannins. Additionally, 24 rats were randomly divided into four groups: a control group, and three groups treated with TMAE (10 mL/kg body weight), 2,4-D (5 mg/kg body weight), and 2,4-D/combined with the TMAE for 4 weeks. Treatment with 2,4-D induced kidney dysfunctions demonstrated as an increase in the potential markers of renal filtration, namely urea and creatinine, associated with a decrease in uric acid. Moreover, 2,4-D increased malondialdehyde and carbonyl protein levels. Additionally, reduced glutathione (GSH) content, as well as superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione S-transferase (GST) activities were significantly decreased. Our results demonstrated that oral TMAE supplementation in 2,4-D-treated rats improved and restored some blood parameters and alleviated the adverse cytotoxic effects of 2,4-D by increasing certain antioxidants, consequently attenuating the intensity of oxidative stress induced by 2,4-D; this was confirmed by the histological improvements observed in the kidneys. In conclusion, TMAE demonstrated potential as a natural antioxidant, effectively alleviating 2,4-D induced kidney oxidative injury.

Keywords: Thymus munbyanus; 2,4-D; kidney; oxidative stress; rat.