Retrograded Tapioca Starch Prevents Ovarian Hormone Deficiency-Induced Hypercholesterolemia

Abstract

SummaryThe purpose of this study was to examine whether retrograded tapioca starch (RS3-tapioca) prevents ovarian hormone deficiency-induced hypercholesterolemia. Sixmonth-old Wistar female rats were subjected to sham-operation or ovariectomy, and fed a cholesterol-free purified diet with or without RS3-tapioca (150 g/kg diet) instead of digestible cornstarch for 28 d. Body weight gain and food intake increased in ovariectomized rats (OVX-rats). Plasma total cholesterol concentration was lowered by RS3-tapioca in OVX rats, but not in sham-operated rats. Liver lipids increased in OVX-rats, but liver cholesterol concentration was not affected by ovariectomy and RS3-tapioca. CYP7A1 activity, small intestinal and cecal bile acid content, and fecal bile acid excretion were increased by RS3-tapioca. The ratio of cholic acid groups to chenodeoxycholic acid groups in the bile acid of the small intestine was increased by RS3-tapioca. Thus, the preventive effect of RS3-tapioca on the ovarian hormone deficiency-associated increase in plasma cholesterol concentration appears to be mediated by accelerated fecal excretion of bile acid and an increase in the intestinal pool of bile acid. Key Words retrograded tapioca starch (RS3-tapioca), ovariectomized rats, plasma cholesterol Resistant starch (RS) is, by definition, the sum of starch and the products of starch degradation not absorbed in the small intestine of healthy individuals ( 1 ). RS is now organized into four categories: physically inaccessible starch (RS1), resistant granules and high amylose starches (RS2), retrograded starches (RS3) and chemically modified starches (RS4) ( 2 ). RS appears to have various physiological effects, such as a decrease in postprandial glycemic and insulinemic responses, reduction of plasma cholesterol and triglyceride concentrations, an improvement in whole body insulin sensitivity, an increase in satiety, and a reduction in fat storage ( 3 ).Menopause, whether natural or surgically induced, is associated with elevated concentrations of circulating total cholesterol and low-density lipoprotein-cholesterol, Placing postmenopausal women at greater risk of coronary heart disease (CHD) ( 4 -7 ). Estrogen replacement therapy (ERT) in postmenopausal women reduces the risk of CHD, in part, by modulating plasma cholesterol; however ERT and cholesterol-lowering pharmacological agents may have side effects.Starch consists of a mixture of two polymers, amylose and amylopectin. Different starches have different relative ratios of amylose and amylopectin. The properties of a starch are highly influenced by the structure of its components. The different properties depend on the crystalline ultra-structure, which differs according to the origin of the starch. X-ray diffraction has been used to characterize the crystalline/amorphous nature of starches. The X-ray diffraction pattern of tapioca starch is C type, while that of corn, potato and rice starch is A, B and A type, respectively. The physical and chemical properties of RS3-tapioca may differ from t...

Hypocholesterolemic effect of capsaicinoids by increased bile acids excretion in ovariectomized rats

“…In the OVX rats, plasma triacylglycerol and cholesterol concentrations, particularly the LDL-C level, were significantly increased, and triacylglycerol and cholesterol accumulations in the liver were elevated. These results agree with those of previous studies [33][34][35]. However, supplementation of capsaicinoids in diet can favorably modify the plasma lipoprotein profile by decreasing plasma TC, LDL-C, and TG, and reducing the concentrations of hepatic cholesterol and triacylglycerol in OVX rats.…”

The mechanism of the cholesterol-lowering effect of water-insoluble fish protein in ovariectomised rats

“…5α-Cholestane (Nacalai Tesque Inc., Kyoto, Japan) was used as the initial standard for cholesterol analysis. The amount and composition of bile acid in bile were analysed by a capillary GLC (model HP5890A; Hewlett Packard, Palo Alto, CA, USA) equipped with a flame-ionisation detector and a capillary column (30 m × 0·25 mm inner diameter) coated with DB-210 (J&W Scientific, Folsom, CA, USA) ( 25 ) . The oven temperature was programmed to increase from 60 to 235°C at the rate of 10°C/min, and the flow rate of the He carrier gas was 1·5 ml/min.…”

Composition, structure, physicochemical properties, and modifications of cassava starch

“…Thus developing high-amylose starch may be 673 useful for the in vivo cholesterol lowering. Retrograded cassava starch (type III resistant 674 starch) was able to prevent ovarian hormone deficiency-induced hypercholesterolemia in 675 female rats(Liu et al, 2006). This effect appeared to be mediated by the increased intestinal676 pool of bile acid and its accelerated fecal excretion (Liu et al, 2006).…”