A comparative study on the effects of Linum usitatissimum and Rosa domascena hydro-alcoholic extracts on body weight, thyroid hormones, and lipids profiles in rats

 Thyroid gland has a major function in the metabolism. Overweight lead to cardiovascular diseases. Linum usitatissimum and Rosa domascena are used in traditional medicine for weight loss.This study was done for find the mechanism of these plants; also compare their effects on weight, thyroid hormones, and lipids profile in rats. 36 Wistar male rats were studied (control and 5 experimental groups) for 28 days. One day after the last intraperitoneally injection, rats were weighted, blood sampling was done and sera were separated. Lipids and thyroid hormones were assayed by biochemistry and Immunoassay methods, respectively. Data were analyzed at P<0.5 level, by ANOVA, one way and t test via SPSS Inc., Chicago, IL; version 18. Increases in T3 hormone in all groups (except the group receiving Rosa domascena at a dose of mg/kg500) and decreases in TSH in all groups compared to the control group were observed (P≤0.05). Weight loss was shown in all studied rats (group1 P=0.03, group2 P= 0.042, groups3, 4, 5 P=0.000). In all groups, the levels of triglyceride decreased (groups 1, 2, 3, 4, 5 P=0.034, 0.05, 0.03, 0.02, 0.03). There were increase in the HDL and decrease in the VLDL in groups receiving high dose of Linum usitatissimum and Rosa domascena, as well as the group receiving these two extracts simultaneously, in comparison with the control group (P≤0.05). LDL level, in group 5, was lower compared to the control group (P≤0.05). Rosa domascena and Linum usitatissimum increase T3 and decrease TSH, these lead to reduction in lipid index and ultimately a loss in weight.The effect of Rosa domascena is more significant than Linum usitatissimum.