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Cholesterol Feeding (cholesterol + feeding)
Selected AbstractsCholesterol Feeding Reduces Vascular Endothelial Growth Factor Signaling in Rabbit Corporal TissuesTHE JOURNAL OF SEXUAL MEDICINE, Issue 5 2005Donghua Xie MD ABSTRACT Purpose., Hypercholesterolemia is a major risk factor for erectile dysfunction (ED), but the mechanisms are not completely understood. Vascular endothelial growth factor (VEGF) is reduced in rabbit corporal tissue with cholesterol feeding. VEGF signaling leads to the phosphorylation of Akt and endothelial nitric oxide synthase (p-Akt and p-eNOS). Material and Methods., New Zealand White rabbits (n = 50) were fed a 1% cholesterol (n = 8, 8, 8, 4) or normal (n = 6, 6, 6, 4) diet for 2, 4.5, 7.5, and 12 weeks. Akt, p-Akt, and p-Akt/Akt were measured by enzyme-linked immunosorbent assay. Levels of eNOS, p-eNOS, and neuronal and inducible nitric oxide synthase (nNOS and iNOS) mRNA and protein were assessed by polymerase chain reaction and Western analysis. Results., Cholesterol feeding was associated with a significant decrease in p-Akt/Akt 2.16-fold (P < 0.05), 3.28-fold (P < 0.02), and 3.42-fold (P < 0.02) at 4.5, 7.5, and 12 weeks., respectively. The reduction in p-Akt/Akt with the cholesterol diet at 2 weeks was not significantly different, but the correlation between the duration of cholesterol feeding and the reduction in p-Akt/Akt was high (r,2 = 0.858). eNOS protein or mRNA did not change with cholesterol feeding, but p-eNOS was significantly decreased at 4.5 weeks and all subsequent time points. nNOS mRNA and protein levels were decreased at 4.5 weeks and all subsequent time points, while iNOS was not different between groups. Conclusions., Hypercholesterolemia results in decreased VEGF signaling and decreased levels of the active form of eNOS in corporal tissue. Levels of nNOS were reduced by a different mechanism. VEGF signaling may provide a target to modulate ED. Xie D, Kontos CD, Donatucci CF, and Annex BH. Cholesterol feeding reduces vascular endothelial growth factor signaling in rabbit corporal tissues. J Sex Med 2005;2:634,640. [source] Effect of sodium phytate supplementation on fat digestion and cholesterol metabolism in female ratsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 11-12 2005C. Yuangklang Summary The effects of sodium phytate supplementation on fat digestion and cholesterol metabolism were investigated in female rats. On the basis of an in vitro experiment showing that phytate raised the solubility of bile acids, it was predicted that phytate feeding would depress faecal bile acid excretion, raise apparent fat digestibility and elevate serum cholesterol concentrations. The experimental diets with or without sodium phytate were either cholesterol-free or cholesterol-rich and had a normal calcium concentration. Rats fed on the cholesterol-rich diet with sodium phytate showed enhanced faecal bile acid excretion, but there was no effect on fat digestibility. In rats fed the cholesterol-free diets, phytate did neither affect fat digestion nor bile acid excretion. Sodium phytate inclusion in the cholesterol-rich diet raised serum cholesterol concentrations, but reduced liver cholesterol concentration. Thus, the in vivo data do not agree with the in vitro observations. Both phytate and cholesterol feeding influenced mineral and trace element metabolism. Liver zinc concentrations were raised by phytate feeding. Cholesterol consumption reduced hepatic concentrations of copper, iron and zinc. Both phytate and cholesterol feeding reduced the apparent absorption of calcium, magnesium and phosphorus. [source] LIPID-LOWERING EFFECTS OF ARONIA MELANOCARPA FRUIT JUICE IN RATS FED CHOLESTEROL-CONTAINING DIETSJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2007S. VALCHEVA-KUZMANOVA ABSTRACT Aronia melanocarpa fruit juice (AMFJ) is very rich in phenolic antioxidants, mainly flavonoids from the subclass anthocyanins. The aim of this study was to assess the influence of AMFJ on body and liver mass, plasma lipids and lipoprotein profiles, and the histopathology of liver and aorta in rats fed with cholesterol diets. AMFJ was applied orally for 30 days at doses of 5, 10 and 20 mL/kg. In rats fed the cholesterol-containing diets, AMFJ significantly hindered an increase in plasma lipids (total cholesterol, low-density lipoprotein cholesterol and triglycerides) because of cholesterol feeding. Body weight gains, liver weights, and liver and aorta histopathology were not influenced either by high-cholesterol diets or by AMFJ treatment. In conclusion, AMFJ showed lipid-lowering effects in rats with experimentally induced hyperlipidemia, and could be valuable in reducing lipidemia as a factor of cardiovascular risk. PRACTICAL APPLICATIONS Hyperlipidemia characterized by an increase in low-density lipoprotein (LDL) cholesterol and a decrease in high-density lipoprotein cholesterol is one of the major risk factors for atherosclerosis and cardiovascular disease. Plant foods with high contents of phenolic phytochemicals are reported to be inversely correlated with plasma total cholesterol (TC) and LDL cholesterol. Aronia melanocarpa fruits are remarkably rich in phenolic substances. They are used for human consumption as juice, syrup, jam and wine. Our research demonstrated that A. melanocarpa fruit juice hindered the dietary-induced elevation of plasma TC, LDL cholesterol and triglycerides in rats. In view of the results from our experiment, we can suppose that the juice may be further tested for reducing hyperlipidemia in humans and possibly approved a valuable dietary supplement. [source] Effect of hesperidin and naringin on the plasma lipid profile and plasma antioxidant activity in rats fed a cholesterol-containing dietJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2007Shela Gorinstein Abstract The objective of this study was to compare the influence of hesperidin and naringin, the main flavonones of orange and grapefruit, on plasma lipid profile and antioxidant activity in rats fed a cholesterol-containing diet. Sixty male Wistar rats were randomly divided into six groups of 10, named Control, Hesperidin, Naringin, Chol, Chol/Hesperidin and Chol/Naringin. The Control group was fed a basal diet (BD) and 1,2 mL of distilled water. To the BD of the other five groups were added 0.1,0.2 mg of hesperidin dissolved in 1,2 mL of distilled water (Hesperidin group), 0.46,0.92 mg of naringin in 1,2 mL of water (Naringin group), 1% of non-oxidised cholesterol (NOC) and 1,2 mL of water (Chol), 1% of NOC and 0.1,0.2 mg of hesperidin in 1,2 mL of water (Chol/Hesperidin), 1% of NOC and 0.46,0.92 mg of naringin in 1,2 mL of water (Chol/Naringin). After 30 days of the experiment it was found that the diets supplemented with hesperidin and naringin increased the plasma antioxidant activity. In conclusion, diets supplemented with hesperidin and naringin significantly hindered the increase in plasma lipid levels caused by cholesterol feeding. Hesperidin and naringin, bioactive compounds of citrus fruits, are powerful plasma lipid lowering and plasma antioxidant activity increasing flavonones. Copyright © 2007 Society of Chemical Industry [source] Cholesterol Feeding Reduces Vascular Endothelial Growth Factor Signaling in Rabbit Corporal TissuesTHE JOURNAL OF SEXUAL MEDICINE, Issue 5 2005Donghua Xie MD ABSTRACT Purpose., Hypercholesterolemia is a major risk factor for erectile dysfunction (ED), but the mechanisms are not completely understood. Vascular endothelial growth factor (VEGF) is reduced in rabbit corporal tissue with cholesterol feeding. VEGF signaling leads to the phosphorylation of Akt and endothelial nitric oxide synthase (p-Akt and p-eNOS). Material and Methods., New Zealand White rabbits (n = 50) were fed a 1% cholesterol (n = 8, 8, 8, 4) or normal (n = 6, 6, 6, 4) diet for 2, 4.5, 7.5, and 12 weeks. Akt, p-Akt, and p-Akt/Akt were measured by enzyme-linked immunosorbent assay. Levels of eNOS, p-eNOS, and neuronal and inducible nitric oxide synthase (nNOS and iNOS) mRNA and protein were assessed by polymerase chain reaction and Western analysis. Results., Cholesterol feeding was associated with a significant decrease in p-Akt/Akt 2.16-fold (P < 0.05), 3.28-fold (P < 0.02), and 3.42-fold (P < 0.02) at 4.5, 7.5, and 12 weeks., respectively. The reduction in p-Akt/Akt with the cholesterol diet at 2 weeks was not significantly different, but the correlation between the duration of cholesterol feeding and the reduction in p-Akt/Akt was high (r,2 = 0.858). eNOS protein or mRNA did not change with cholesterol feeding, but p-eNOS was significantly decreased at 4.5 weeks and all subsequent time points. nNOS mRNA and protein levels were decreased at 4.5 weeks and all subsequent time points, while iNOS was not different between groups. Conclusions., Hypercholesterolemia results in decreased VEGF signaling and decreased levels of the active form of eNOS in corporal tissue. Levels of nNOS were reduced by a different mechanism. VEGF signaling may provide a target to modulate ED. Xie D, Kontos CD, Donatucci CF, and Annex BH. Cholesterol feeding reduces vascular endothelial growth factor signaling in rabbit corporal tissues. J Sex Med 2005;2:634,640. [source] | ||||||||||