Vaspin Gene Expression in Rat Adipose Tissue: Relation to Obesity and Exercise,SANDRA M. YOUNAN, MARY A. YOUSSEF and OLFAT SHAKER
Abstract
Visceral adipose fat has been claimed by many studies to be the link between obesity and insulin resistance through the released adipokines. The aim of this study was to assess the effect of obesity and exercise on expression of vaspin as one of the recent adipokines in abdominal subcutaneous and visceral fat of diet-induced obese (DIO) rats and DIO rats performing 3 weeks swimming exercise (DIO+EXE) compared to control and control+exercise (C+EXE) groups and to evaluate vaspin’s correlation with the visceral fat weight, insulin resistance and serum leptin level.
Vaspin mRNA expression was detected in the obese and not in the control group. Moreover it was frequently detected in the DIO abdominal visceral fat compared to the subcutane-ous one positively correlated with the body weight and insulin resistance, suggesting a role of vaspin in obesity induced insulin resistant states.
Vaspin expression was absent in C+EXE group. Also visceral vaspin mRNA was unchanged in DIO+EXE rats (26.7% versus 40% of cases in DIO), in spite the significant improvements of insulin resistance parameters and serum leptin compared to DIO group denoting that vaspin expression is not related to exercise but rather to the increase in body weight which was not significantly changed by exercise alone.
In Conclusion: Visceral vaspin expression increases in obesity associated with insulin resistance and is unchanged by exercise. Further investigations into the molecular links between vaspin and obesity may unravel innovative therapeutic strategies in people affected by obesity-linked insulin resis-tance, metabolic syndrome, and type 2 diabetes.