The Effect of Dietary Wild Pistachio Oil (Pistacia atlantica) on Serum Thyroid Hormones and Leptin Concentration in Experimental Hyperthyroidism in the Female Rat

Unsaturated fatty acids such as turpentine oil can decrease serum leptin level with attention to this effect and the axial role of thyroid hormones and leptin in metabolism, the aim of the present study was to investigate the impact of dietary wild pistachio oil on serum leptin concentration and its relationship with thyroid hormones in experimental hyperthyroidism in Sprague Dawely female rat. 30 healthy adult female rats was selected and divided into five groups. Animals were fed with normal diet, levothyroxine plus normal diet, and 5, 10, 20 percent of turpentine oil plus normal diet respectively. Duration of the study was one month sampling obtained in each ten day intervals. Hyperthyroidism was created in animals with dosage of 12 mg/l of levothyroxine in drinking water for one month. Rats treated with 5%, 10% and 20% concentrations of wild pistachio oil for one month. Blood samples were collected from heart in each ten days interval. No difference was observed in thyroid hormones and leptin in control group (P>0.05). With an increasing in turpentine oil in diet a significant reduction was obtained for T4, T3 and fT4 respectively (P<0.05). A significant decrease also was observed with increase of 10 and 20 percent of turpentine oil in serum leptin level as compared to control group (P<0.05). There is a clear relationship between percent of turpentine oil feeding and thyroid and leptin hormone levels in experimental hyperthyroidism rats (P<0.05). Wild pistachio oil had been positive impression on reducing hyperthyroidism effects especially T4 concentration (P<0.05). Wild pistachio oil usage in the hyperthyroidismic rats caused to decrease significantly the serum concentration of leptin during the experimental period (P<0.05). There is a clear relationship between percent of turpentine oil feeding and thyroid and leptin hormone levels in experimental hyperthyroidism rats. Therefore, this study indicates that consumption of turpentine oil could induce the renovation of hyperthyroidism from regulation of leptin secretion and metabolism.