RESUMO
Acceleration of natural ageing occurs due to multiple reasons such as stress, obesity and Type 2 diabetes working in a vicious cycle. In the present study, we tested if superimposing type 2 diabetes in a rat model of obesity accelerates ageing or not. We aggravated insulin resistance/ induced type 2 diabetes by feeding high sucrose diet (HSD) to 9-10 wk old, male, WNIN/Gr-Ob obese rats. We report here the changes in physiological, biochemical and histological parameters after 3 and 6 months of feeding. Rats fed HSD had the highest insulin resistance as evident from increased HOMA IR and AUC insulin during OGTT. Body weight gain and Food efficiency ratio (FER) were also significantly higher in HSD fed than the control rats after 6 months of feeding. Further, liver steatosis and kidney damage were the highest in the HSD fed rats as evident from ORO staining. Interestingly, HSD fed rats also had the highest intensity of ß-cell staining and functioning (as indicated by higher HOMA-ß). The findings indicate that parameters associated with ageing were accelerated in WNIN/Gr-Ob rats fed HSD, implying that aggravating insulin resistance in obese rats may be associated with accelerated ageing.
RESUMO
To determine the association between thyroid hormones, insulin resistance, and metabolic syndrome in euthyroid women. Forty-five women with no past medical history were studied in this cross-sectional study at the Department of Endocrinology, Medwin Hospitals, Hyderabad, India, from August 2008 to September 2008. The body fat was estimated using bio-impedance method, and fasting blood sample was analyzed for total triiodothyronine [T3], total thyroxine [T4], thyroid-stimulating hormone [TSH], free triiodothyronine [FT3], lipid profile, insulin, and glucose. The mean age of the participants was 32.6 +/- 9.6 years with a body mass index [BMI] of 29.9 +/- 3.8 kg/m[2]. Evidence of homeostasis model assessment index for insulin resistance [HOMA-IR] more than 3 was seen in 34 [75%] and metabolic syndrome in 29 [64%] participants. Total T3 showed a positive correlation with triglycerides, low density lipoproteincholesterol [LDL-C], total cholesterol, insulin, HOMA-IR and negatively with body fat. Thyroid-stimulating hormone correlated positively with BMI, insulin, HOMA-IR, LDL-C and negatively with HDL-cholesterol [p<0.05]. Free triiodothyronine correlated positively with waist circumference and T4 did not correlate with metabolic syndrome parameters. Our preliminary data show an association between thyroid hormones and some components specific of the metabolic syndrome in euthyroid women. Total triiodothyronine and TSH correlated more with variables of metabolic syndrome than FT3 and T4