Hypothyroidism and Obesity: Resistin May Inversely be Associated with Thyroid Function
School of Kinesiology, Shanghai University of Sport, Shanghai 200438, 1Institute of Physical Education, Baise University, Baise 533000, 2School of Sports and Health, Guangzhou Sport University, Guangzhou 510500, China
W. LIN, Institute of Physical Education, Baise University, Baise 533000, 2School of Sports and Health, Guangzhou Sport University, Guangzhou 510500, China, E-mail: email@example.com
Resistin plays an important role in the body’s metabolic system and its devastation is associated with obesity. Thyroid hormones also play a role in regulating the body’s overall metabolism. So in this experimental study, we tried to investigate the relationship between the resistin gene expression and thyroid hormones in Wistar rat. For experiments, 24 Wistar rats, were used to develop obesity (obese group, n=8) or hypothyroidism (hypothyroid group, n=8); also 8 rats were used as control. To cause obesity in obese rats, they were kept for 60 d and fed with a high fat diet. Propylthiouracil was used to induce hypothyroidism. Resistin messenger ribonucleic acid expression was evaluated by real time polymerase chain reaction in all rats. Data were compared between the groups of study by statistical package for the social sciences. The results showed that the obese group had a significantly higher weight than the two hypothyroid and control groups (p<0.05). However, the hypothyroid group, despite having a higher average weight than the control group, did not have a statistically significant difference in weight with the control group (p=0.067). Examination of triiodothyronine and thyroxine hormones also showed that the hypothyroid group had significantly lower triiodothyronine and thyroxine than both control and obese groups (p<0.05). However, the two groups of obesity and control did not differ in terms of the level of these hormones (p>0.05). The results of the study of the relative expression of resistin gene in the three study groups did not show a significant difference (p>0.05). However, the control group had less expression than the two obese and hypothyroid groups. Separating animals to 2 groups of high resistin and low resistin expression revealed higher triiodothyronine and thyroxine in a group of animals expressing low resistin (p<0.05). There were so many controversies between studies and this disagreement could be because of serum resistin. The short half-life of resistin cannot be considered for the study of resistin and as well as the human studies should also assess its expression.