Effects of essential oil of Satureja khuzestanica on the oxidative stress in experimental hyperthyroid male rat

This work analyzes the effects of Satureja khuzestanica essential oil (SKEO) on the thyroid and antioxidant system, assessed by measuring levels of tri-iodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), malondialdehyde (MDA), reduced glutathione (GSH), and glutathione peroxidase (GPx) activity. Forty adult male Sprague Dawley rats (225 ± 25 g) were divided into five equal groups: one control and four hyperthyroid groups that received placebo, 200 mg kg-1 body weight of vitamin (Vit.) E, 225 mg kg-1 body weight of SKEO, 200 and 225 mg kg-1 body weight of Vit. E and SKEO together, respectively. Hyperthyroidism was induced by administering of L-thyroxin in drinking water. After 30 days of L-thyroxin consumption, serum T3 and T4 levels, TSH, and oxidative stress indices were determined. Significant increase in serum T3, T4 and MDA concentrations with a simultaneous significant decrease in TSH, GSH level and GPx activity were observed in hyperthyroid group (p < 0.05). In the treatment groups, SKEO and/or Vit. E can compensate serum MDA elevation and GPx activity reduction. Only, SKEO + Vit. E could compensate the decline of GSH levels in response to hyperthyroidism. Supplementation of SKEO, plus Vit. E as antioxidants is useful in attenuating lipid peroxidation and may potentially benefit hyperthyroid patients.