Increasing Angiotensin (1-7) Levels in the Brain Attenuates Metabolic Syndrome related risks in Fructose-Fed Rats

Priscila S. Guimaraes, Mariana F. Oliveira, Janaína F. Braga, Ana Paula Nadu, Ann Schreihofer, Robson A.S. Santos and Maria Jose Campagnole-Santos Hypertension. published online February 10, 2014; In this study they investigated fructose fed diet and the role of angiotensin (1-7) in the brain. In this study they had a group that received intracerebroventricular infusion of Ang (1-7) FF+A7, and a fructose fed group that received an introcerebroventricular infusion of 0.9% saline (FF). Both groups received the infusions for 4 weeks. They looked at the baroreceptor reflex responses for arterial pressure, cardiac sympathethetic/ parasymthetic tone, and heart rate. They found that in the FF+A7 group that the arterial pressure and cardiac sympathetic tone are significantly reduced compared to the FF group. They also measured metabolic parameters and found that Glucose, insulin, and insulin resistance is significantly reduced in FF+A7 compared to FF. they also found that Leptin, HDL and triglycerides were significantly elevated compared to control group. They also measured glycogen in the liver and found that it was significantly higher in the FF+A7 compared to the FF. however the glycogen stores in the muscle was significantly lower in the FF+A7 compared to the FF. Blood glucose was lower in the FF+A7 compared to the FF. They also looked the expression of the Mas receptor, nNOS and NR1/NMDAr in the hypothalamus and dorsomedial medulla and they found that the mRNA expression of NR1 and nNOS was significantly reduced in the FF+A7 compared to FF in both the hypothalamus and the dorsomedial medulla. These findings suggest that Ang (1-7) may improve metabolic parameters along with blood pressure and cardiovascular responses to fructose diet induced changes in the body.-MD