Effect of adlay, buckwheat and barley on lipid metabolism and aorta histopathology in rats fed an obesogenic diet

Background/Aims: The present study was carried out to evaluate the nutritional quality of adlay (AD), buckwheat (BW) and waxy barley (WB), with particular respect to their fiber components. Plasma lipid parameters, gut transit time and thickness of the aortic wall in rats fed with different grains were evaluated and compared with rats fed on white rice (WR). Methods: The rats were then raised for 4 weeks on an obesogenic diet based on the American Institute of Nutrition-93 (AIN-93 G) diets containing 1% cholesterol and 20% dietary lipids. 40 male rats were divided into 4 groups and raised for 4 weeks with a diet containing one of the following grains: WR, AD, BW, or WB. Results: Gut transit time was shortened depending on the grain, with the WB group having the shortest time, followed by the BW group and the AD group, and then the WR group. Plasma lipid profiles differed significantly according to grain combination, and the levels of triglycerides in the AD, BW and WB groups were significantly lower than that in the WR group. The BW and WB groups showed lower levels of total cholesterol and LDL-C, and higher HDL-C than the WR group, although the group fed on AD did not show such results owing to the high content of lipids and calories. Accordingly, the reduction in gut transit time resulted in decreasing levels of triglycerides, total cholesterol and LDL-C. Rats fed on WB and BW showed significantly larger aortic lumen than those fed with AD and WR. Also the wall thickness of the WB group was significantly thinner than that of the WR group. Conclusion: Consumption of BW- and WB-containing diets significantly improved several cardiovascular risk factors induced by obesity in experimental rats. Copyright (C) 2008 S. Karger AG, Basel.