Short-Term Effects of Sleeve Gastrectomy and Caloric Restriction on Blood Pressure in Diet-Induced Obese Rats

Abstract

Sleeve gastrectomy constitutes an effective surgical procedure for the treatment of morbid obesity. The aim of the present study was to establish the effects of sleeve gastrectomy and caloric restriction on weight loss and cardiovascular parameters in diet-induced obese (DIO) rats. Male Wistar DIO rats were subjected to surgical interventions (n = 30) (sham operation, sleeve gastrectomy, or pair-fed to the amount of food eaten by sleeve-gastrectomized animals and compared to lean control rats) or dietary interventions (n = 40) (fed ad libitum a normal diet (ND) or a high-fat diet or an ND with a caloric restriction of 25 %). Systolic blood pressure (SBP), diastolic blood pressure, and mean blood pressure values and heart rate (HR) were recorded in conscious, resting animals by noninvasive tail-cuff plethysmography before and 3 weeks after surgical or dietary interventions. Both sleeve gastrectomy and caloric restriction induced a reduction in body weight, whole-body adiposity, and serum leptin together with an increased excess weight loss in DIO rats. Sleeve gastrectomy was further associated with an improvement in insulin resistance and the lipid profile, as well as with a reduction in serum ghrelin levels. A decrease in HR and heart weight was observed in caloric-restricted groups. Sleeve-gastrectomized rats not only exhibited a reduction in HR (∆HR = -45 ± 19 bpm) but also in SBP values (∆SBP = -22 ± 10 mmHg) compared to the DIO rats (∆SBP = 14 ± 8 mmHg). Our findings provide evidence that the beneficial effects of sleeve gastrectomy on blood pressure values are beyond weight loss in rats with diet-induced obesity.