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Talati R, Baker WL, Pabilonia MS, White CM, Coleman CI. The effects of barley-derived soluble fiber on serum lipids. Ann Fam Med 2009; 7:157-63. [PMID: 19273871 PMCID: PMC2653960 DOI: 10.1370/afm.917] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 07/15/2008] [Accepted: 07/30/2008] [Indexed: 02/06/2023] Open
Abstract
PURPOSE We wanted to determine the association between consumption of barley and changes in plasma lipids in healthy and hypercholesterolemic men and women. METHODS A systematic literature search was conducted from the earliest possible date through January 2008. Trials were included in the analysis if they were randomized controlled trials of barley that reported efficacy data on at least 1 lipid endpoint. A DerSimonian and Laird random-effects model was used in calculating the weighted mean difference (WMD) and its 95% confidence interval (CI). Statistical heterogeneity was addressed using the I(2) statistic. Visual inspection of funnel plots, Egger's weighted regression statistics, and the trim and fill method were used to assess for publication bias. RESULTS We found 8 trials (n = 391 patients) of 4 to 12 weeks' duration evaluating the lipid-reducing effects of barley. The use of barley significantly lowered total cholesterol (weighted mean difference [WMD], -13.38 mg/dL; 95% CI, -18.46 to -8.31 mg/dL), low-density lipoprotein (LDL) cholesterol (WMD, -10.02 mg/dL; 95% CI, -14.03 to -6.00 mg/dL) and triglycerides (WMD, -11.83 mg/dL; 95% CI, -20.12 to -3.55 mg/dL) but did not appear to significantly alter high-density lipoprotein (HDL) cholesterol (P=.07). CONCLUSION Barley-derived beta-glucan appears to beneficially affect total cholesterol, LDL-cholesterol, and triglycerides, but not HDL-cholesterol.
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Affiliation(s)
- Ripple Talati
- University of Connecticut School of Pharmacy, Storrs, Connecticut, USA
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Wilson TA, Nicolosi RJ, Woolfrey B, Kritchevsky D. Rice bran oil and oryzanol reduce plasma lipid and lipoprotein cholesterol concentrations and aortic cholesterol ester accumulation to a greater extent than ferulic acid in hypercholesterolemic hamsters. J Nutr Biochem 2007; 18:105-12. [PMID: 16713234 DOI: 10.1016/j.jnutbio.2006.03.006] [Citation(s) in RCA: 181] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Revised: 03/17/2006] [Accepted: 03/21/2006] [Indexed: 10/24/2022]
Abstract
Our laboratory has reported that the hypolipidemic effect of rice bran oil (RBO) is not entirely explained by its fatty acid composition. Because RBO has a greater content of the unsaponifiables, which also lower cholesterol compared to most vegetable oils, we wanted to know whether oryzanol or ferulic acid, two major unsaponifiables in RBO, has a greater cholesterol-lowering activity. Forty-eight F(1)B Golden Syrian hamsters (Mesocricetus auratus) (BioBreeders, Watertown, MA) were group housed (three per cage) in cages with bedding in an air-conditioned facility maintained on a 12-h light/dark cycle. The hamsters were fed a chow-based hypercholesterolemic diet (HCD) containing 10% coconut oil and 0.1% cholesterol for 2 weeks, at which time they were bled after an overnight fast (16 h) and segregated into 4 groups of 12 with similar plasma cholesterol concentrations. Group 1 (control) continued on the HCD, group 2 was fed the HCD containing 10% RBO in place of coconut oil, group 3 was fed the HCD plus 0.5% ferulic acid and group 4 was fed the HCD plus 0.5% oryzanol for an additional 10 weeks. After 10 weeks on the diets, plasma total cholesterol (TC) and non-high-density lipoprotein cholesterol (HDL-C) (very low- and low-density lipoprotein) concentrations were significantly lower in the RBO (-64% and -70%, respectively), the ferulic acid (-22% and -24%, respectively) and the oryzanol (-70% and -77%, respectively) diets compared to control. Plasma TC and non-HDL-C concentrations were also significantly lower in the RBO (-53% and -61%, respectively) and oryzanol (-61% and -70%, respectively) diets compared to the ferulic acid. Compared to control and ferulic acid, plasma HDL-C concentrations were significantly higher in the RBO (10% and 20%, respectively) and oryzanol (13% and 24%, respectively) diets. The ferulic acid diet had significantly lower plasma HDL-C concentrations compared to the control (-9%). The RBO and oryzanol diets were significantly lower for plasma triglyceride concentrations compared to the control (-53% and -65%, respectively) and ferulic acid (-47% and -60%, respectively) diets. Hamsters fed the control and ferulic acid diets had significantly higher plasma vitamin E concentrations compared to the RBO (201% and 161%, respectively) and oryzanol (548% and 462%, respectively) diets; the ferulic acid and oryzanol diets had significantly lower plasma lipid hydroperoxide levels than the control (-57% and -46%, respectively) diet. The oryzanol-fed hamsters excreted significantly more coprostenol and cholesterol in their feces than the ferulic acid (127% and 120%, respectively) diet. The control diet had significantly greater aortic TC and FC accumulation compared to the RBO (115% and 89%, respectively), ferulic acid (48% and 58%, respectively) and the oryzanol (74% and 70%, respectively) diets. However, only the RBO and oryzanol diets had significantly lower aortic cholesterol ester accumulation compared to the control (-73% and -46%, respectively) diet. The present study suggests that at equal dietary levels, oryzanol has a greater effect on lowering plasma non-HDL-C levels and raising plasma HDL-C than ferulic acid, possibly through a greater extent to increase fecal excretion of cholesterol and its metabolites. However, ferulic acid may have a greater antioxidant capacity via its ability to maintain serum vitamin E levels compared to RBO and oryzanol. Thus, both oryzanol and ferulic acid may exert similar antiatherogenic properties, but through different mechanisms.
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Affiliation(s)
- Thomas A Wilson
- Department of Clinical Laboratory and Nutritional Sciences, Center for Health and Disease Research, University of Massachusetts Lowell, Lowell, MA 01854, USA.
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Muwalla MM, Abuirmeileh NM. Suppression of avian hepatic cholesterogenesis by dietary ginseng. J Nutr Biochem 2005; 1:518-21. [PMID: 15539168 DOI: 10.1016/0955-2863(90)90034-i] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/1989] [Accepted: 05/21/1990] [Indexed: 10/27/2022]
Abstract
The effect of the ginseng root powder on avian hepatic cholesterol biosynthesis and serum lipoprotein cholesterol levels were examined. Lohman strain broiler females were fed for 4 weeks a corn-based diet (control) or an experimental diet in which 0.25% Korean ginseng was incorporated (treatment). B.-hydroxy-B-methylglutaryl-CoA) HMG-CoA reductase activity was significantly lower (P < 0.01) in the treatment group (47% of control activity). Ginseng treatment affected a lowering of the serum total cholesterol level (83% of control, (P < 0.05) and of serum low density lipoprotein cholesterol level (77% of control, P < 0.05). The mechanism of the hypocholesterolemic action of ginseng involves the suppression of cholesterol biosynthesis.
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Affiliation(s)
- M M Muwalla
- Department of Veterinary Medicine and Agricultural Sciences, College of Agriculture and Veterinary Science, Jordan University of Science and Technology, Irbid, Jordan
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Noh SK, Koo SI, Jiang Y. (+)-Catechin is a Potent Inhibitor of Intestinal Absorption of Cholesterol in Rats. Prev Nutr Food Sci 2003. [DOI: 10.3746/jfn.2003.8.1.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Kim HK, Chang YJ, Heo HJ, Cho HY, Hong BS, Shin DH. Hypocholesterolemic Effect of Amaranth Squalene (Amaranth esculantus) in Rats Fed a High Cholesterol Diet. Prev Nutr Food Sci 2003. [DOI: 10.3746/jfn.2003.8.1.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Qureshi AA, Peterson DM, Hasler-Rapacz JO, Rapacz J. Novel tocotrienols of rice bran suppress cholesterogenesis in hereditary hypercholesterolemic swine. J Nutr 2001; 131:223-30. [PMID: 11160537 DOI: 10.1093/jn/131.2.223] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A tocotrienol-rich fraction (TRF(25)) and novel tocotrienols (d-P(21)-T3 and d-P(25)-T3) of rice bran significantly lowered serum and low density lipoprotein cholesterol levels in chickens. The present study evaluated the effects of novel tocotrienols on lipid metabolism in swine expressing hereditary hypercholesterolemia. Fifteen 4-mo-old genetically hypercholesterolemic swine were divided into five groups (n = 3). Four groups were fed a corn-soybean control diet, supplemented with 50 microg of either TRF(25), gamma-tocotrienol, d-P(21)-T3 or d-P(25)-T3 per g for 6 wk. Group 5 was fed the control diet for 6 wk and served as a control. After 6 wk, serum total cholesterol was reduced 32-38%, low density lipoprotein cholesterol was reduced 35-43%, apolipoprotein B was reduced 20-28%, platelet factor 4 was reduced 12-24%, thromboxane B(2) was reduced 11-18%, glucose was reduced 22-25% (P<0.01), triglycerides were reduced 15-19% and glucagon was reduced 11-17% (P<0.05) in the treatment groups relative to the control. Insulin was 100% greater (P<0.01) in the treatment groups than in the control group. Preliminary data (n = 1) indicated that hepatic activity of the 3-hydroxy-3-methylglutaryl-coenzyme A reductase was lower in the treatment groups, and cholesterol 7alpha-hydroxylase activity was unaffected. Cholesterol and fatty acid levels in various tissues were lower in the treatment groups than in control. After being fed the tocotrienol-supplemented diets, two swine in each group were transferred to the control diet for 10 wk. The lower concentrations of serum lipids in these four treatment groups persisted for 10 wk. This persistent effect may have resulted from the high tocotrienol levels in blood of the treatment groups, suggesting that the conversion of tocotrienols to tocopherols may not be as rapid as was reported in chickens and humans.
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Affiliation(s)
- A A Qureshi
- Advanced Medical Research, Madison, Wisconsin 53719, USA.
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Wilson TA, Ausman LM, Lawton CW, Hegsted DM, Nicolosi RJ. Comparative cholesterol lowering properties of vegetable oils: beyond fatty acids. J Am Coll Nutr 2000; 19:601-7. [PMID: 11022873 DOI: 10.1080/07315724.2000.10718957] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE Our laboratory has previously reported that the hypolipidemic effect of rice bran oil (RBO) is not entirely explained by its fatty acid composition. Although RBO has up to three times more serum cholesterol-raising saturated fatty acids (SATS) than some unsaturated vegetable oils, we hypothesized that its greater content of the unsaponifiables would compensate for its high SATS and yield comparable cholesterol-lowering properties to other vegetable oils with less SATS. METHODS To study the comparative effects of different unsaturated vegetable oils on serum lipoprotein levels, nine cynomologus monkeys (Macaca fascicularis) were fed diets, for four weeks, in a Latin square design, containing rice bran, canola or corn oils (as 20% of energy) in a basal mixture of other fats to yield a final dietary fat concentration of 30% of energy. All animals were fed a baseline diet containing 36% of energy as fat with 15% SATS, 15% monounsaturated fatty acids (MONOS) and 6% polyunsaturated fatty acids (POLYS). RESULTS Despite the lower SATS and higher MONOS content of canola oil and the higher POLYS content of corn oil, RBO produced similar reductions in serum total cholesterol (TC) (-25%) and low density lipoprotein cholesterol (LDL-C) (-30%). In addition, as compared to the baseline diet, the reduction in serum TC and LDL-C cholesterol with RBO was not accompanied by reductions in high density lipoprotein cholesterol (HDL-C) which occurred with the other two dietary oils. Using predictive equations developed from data gathered from several studies with non-human primates, we noted that the observed serum TC and LDL-C lowering capabilities of the RBO diet were in excess of those predicted based on the fatty acid composition of RBO. CONCLUSIONS These studies suggest that non-fatty acid components (unsaponifiables) of RBO can contribute significantly to its cholesterol-lowering capability.
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Affiliation(s)
- T A Wilson
- Department of Health and Clinical Science, Center for Chronic Disease Control and Prevention, University of Massachusetts, Lowell 01854-5125, USA
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Konjufca VH, Pesti GM, Bakalli RI. Modulation of cholesterol levels in broiler meat by dietary garlic and copper. Poult Sci 1997; 76:1264-71. [PMID: 9276889 DOI: 10.1093/ps/76.9.1264] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Male Ross x Ross 208 chickens were fed from hatching to 21 d of age either a control diet (based on corn and soybean meal) or the control diet supplemented with 0, 1.5, 3.0, and 4.5% of a commercial garlic powder in Experiments 1 and 2. Once the dose-response relationship was established, 3% garlic powder or 63 or 180 mg/kg copper as cupric citrate or cupric sulfate pentahydrate were supplemented to the diet (Experiments 3, 4, 5, and 6). In the first two experiments, reductions of plasma cholesterol (P = 0.006) and triacylglycerols (P = 0.013) and liver (P = 0.012) and breast muscle (P = 0.165) cholesterol were observed in garlic-supplemented birds. Feeding either garlic powder or copper (63 and 180 mg/kg) resulted in reduced levels of plasma cholesterol, liver cholesterol, blood reduced glutathione, and breast and thigh muscle cholesterol. Differences were significant at P < 0.05 in at least one experiment. 3-Hydroxy-3-methylglutaryl reductase activity was decreased due to dietary garlic (P = 0.0369), but not by pharmacological levels of dietary copper (P = 0.982). The activity of fatty acid synthetase was decreased in birds fed copper (P = 0.035). Both garlic and copper supplements decreased cholesterol 7 alpha-hydroxylase activity (P = 0.024 and P = 0.022, respectively). The results of these trials confirm the findings that garlic and copper alter lipid and cholesterol metabolism. However, they do not work by the same mechanism. Feeding dietary garlic or copper for 21 d reduced cholesterol levels of broiler meat without altering growth of the chickens or feed efficiency.
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Affiliation(s)
- V H Konjufca
- Department of Poultry Science, University of Georgia, Athens 30602-2772, USA
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Wang L, Behr SR, Newman RK, Newman C. COMPARATIVE CHOLESTEROL-LOWERING EFFECTS OF BARLEY β-GLUCAN AND BARLEY OIL IN GOLDEN SYRIAN HAMSTERS. Nutr Res 1997. [DOI: 10.1016/s0271-5317(96)00234-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lupton JR, Robinson MC, Morin JL. Cholesterol-lowering effect of barley bran flour and oil. JOURNAL OF THE AMERICAN DIETETIC ASSOCIATION 1994; 94:65-70. [PMID: 8270757 DOI: 10.1016/0002-8223(94)92044-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE To compare the effects of adding barley bran flour and a barley oil extract to a fat-modified diet on serum lipids in persons with hypercholesterolemia. DESIGN The basic design of the study was a randomized, 30-day intervention trial. It included a neutral-fiber control group and a 1-week preintervention period for the collection of baseline data. SUBJECTS The subjects were 79 men and women with hypercholesterolemia. Subjects had a mean age of 48.2 years, and all completed the study. INTERVENTION All participants were instructed to follow the National Cholesterol Education Program (NCEP) step 1 diet and were randomly assigned to one of three treatment groups: 20 g added cellulose, 3 g added barley oil extract, or 30 g added barley bran flour. MAIN OUTCOME MEASURES Total serum cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and very-low-density lipoprotein cholesterol were measured, along with serum triglycerides, before the intervention, at week 1, at week 3, and at the end of the intervention. STATISTICAL ANALYSES PERFORMED Student's paired t test was used to detect significant changes within each treatment group from baseline to the end of the 30-day intervention. In addition, Pearson's correlation coefficients were used to detect significant correlations between the variables measured. RESULTS Addition of barley bran flour significantly (P = .0001) decreased total serum cholesterol (-0.60 mmol/L) as did addition of barley oil (-0.50 mmol/L; P = .002) after 30 days of intervention. Similarly, LDL-C decreased 6.5% with addition of barley bran flour (P = .036) and 9.2% with addition of barley oil (P = .003). Total serum cholesterol or LDL-C of the cellulose control group did not decrease significantly over the same period. HDL-C decreased significantly in the cellulose control group and the barley bran flour group (-0.15 mmol/L, P = .012, and -0.15 mmol/L, P = .006, respectively), but not in the barley oil group. CONCLUSION We conclude that addition of barley bran flour or barley oil enhances the cholesterol-lowering effect of the NCEP step 1 diet in individuals with hypercholesterolemia.
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Affiliation(s)
- J R Lupton
- Nutrition Faculty, Texas A&M University, College Station 77843-2471
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Lupton JR, Morin JL, Robinson MC. Barley bran flour accelerates gastrointestinal transit time. JOURNAL OF THE AMERICAN DIETETIC ASSOCIATION 1993; 93:881-5. [PMID: 8393033 DOI: 10.1016/0002-8223(93)91526-v] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The effect of barley bran flour on colon physiology was studied in 44 volunteers. Twenty-two subjects followed the National Cholesterol Education Program (NCEP) step 1 diet supplemented with 20 g cellulose and the other 22 followed the NCEP diet supplemented with 30 g barley bran flour. To measure gastrointestinal transit time, subjects ingested 20 polyethylene pellets impregnated with barium sulfate in two gelatin capsules. Subjects collected fecal samples for 5 days during the baseline period and again during the period of fiber supplementation. Each stool sample was radiographed, and the number of recovered markers was used to calculate mean transit time. Daily fecal weights were recorded and dry weights were determined. The group that consumed barley bran flour significantly decreased transit time by 8.02 hours from baseline, whereas the group that consumed cellulose increased transit time by 2.95 hours from baseline. Similarly, cellulose supplementation did not result in increased fecal weight, whereas daily fecal weight increased significantly by 48.6 g with supplementation with barley bran flour. This study shows that barley bran flour accelerates gastrointestinal transit and increases fecal weight.
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Affiliation(s)
- J R Lupton
- Graduate Faculty of Nutrition, Texas A&M University, College Station 77843
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Kruger M, Smuts CM, Benadé AJ, Fincham JE, Lombard CJ, Albertse EA, van der Merwe KJ. Comparison of the effect of the amount and degree of unsaturation of dietary fat on plasma low density lipoproteins in vervet monkeys. Lipids 1992; 27:733-9. [PMID: 1435092 DOI: 10.1007/bf02535842] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The effects of the degree of unsaturation and of the amount of dietary fat on low density lipoprotein (LDL) concentration and composition were determined in vervet monkeys. Diets with fat contents of 41, 31 and 18% energy, each with a low and a high polyunsaturated to saturated fatty acid ratio (P/S; 0.27-0.38 and 1.13-1.47) were fed to six female vervet monkeys for two months. Another six females were given a low fat, high P/S diet for the same period of time, to serve as a reference. The cholesterol contents of the diets were low (21-33 mg per day) and relatively constant. LDL cholesterol concentrations decreased significantly (P < or = 0.01) when the dietary fat content decreased from 31 to 18% of energy. The dietary P/S ratio only affected LDL cholesterol concentrations during moderate (31% of energy) fat intake, where LDL cholesterol increased (P < or = 0.01) with a decrease in dietary P/S. Substantial individual variations were observed in LDL cholesterol concentration responses to dietary fat changes. The changes in LDL cholesterol concentrations were the result of changes in the concentration of LDL particles, as the molecular composition did not differ significantly between dietary periods. The high density lipoprotein cholesterol and the plasma triacylglycerol concentrations were not influenced by the dietary fat changes. During the high P/S diets, the percentage of 18:2 (linoleic acid) increased (P < or = 0.01) and that of 18:1 (oleic acid) decreased (P < or = 0.01) in LDL esterified cholesterol, as compared to the low P/S diets. In adipose tissue triacylglycerol the percentage of 18:2 was three times higher (P < or = 0.01) during the high P/S diets than during the low P/S diets.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M Kruger
- SA Medical Research Council, Tygerberg, South Africa
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Qureshi AA, Crenshaw TD, Abuirmeileh N, Peterson DM, Elson CE. Influence of minor plant constituents on porcine hepatic lipid metabolism. Impact on serum lipids. Atherosclerosis 1987; 64:109-15. [PMID: 3606707 DOI: 10.1016/0021-9150(87)90235-8] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The effects of plant constituents on lipid metabolism were examined in swine that had been fed for 4 weeks a standard diet containing, in addition, (per kg diet) 3.15 g of the methanol serial solvent fraction garlic bulbs or 3.5 g of the petroleum ether solubles high-protein barley flour or 5 mg of the plant growth regulator, AMO 1618. All treatments suppressed 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase and cholesterol 7 alpha-hydroxylase activities. Modest increases in serum triglycerides were associated with significantly increased hepatic lipogenic activities in response to all treatments except that of the barley extract. The methanol solubles of a second lot of garlic were fractionated by HPLC and tested in an avian hepatocyte system. One component, an isoprenoid metabolite, MW 358, suppressed HMG-CoA reductase.
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Qureshi AA, Burger WC, Peterson DM, Elson CE. The structure of an inhibitor of cholesterol biosynthesis isolated from barley. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(18)67419-8] [Citation(s) in RCA: 251] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Elegbede JA, Elson CE, Qureshi A, Dennis WH, Yatvin MB. Increasing the thermosensitivity of a mammary tumor (CA755) through dietary modification. EUROPEAN JOURNAL OF CANCER & CLINICAL ONCOLOGY 1986; 22:607-15. [PMID: 3770032 DOI: 10.1016/0277-5379(86)90051-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Disruption of the integrity of tumor cellular membranes has been proposed as an initiating event in hyperthermic cell death. Thermosensitivity measured by the shift in the harmonic mean of tumor regrowth delay of CA755 mammary adenocarcinomas grown in the hind legs of male BDF1, mice increased 22% when the hosts were fed a diet enriched in polyunsaturated fatty acids. Although the diet elicited the anticipated increase in tumor membrane phospholipid polyunsaturated fatty acids, the proportion of total unsaturated fatty acids decreased and the proportion of membrane-rigidifying saturated fatty acids increased. Concomitantly, the concentrations of cholesterol and phospholipid phosphorus increased and the ratio of phosphatidylethanolamine to phosphatidylcholine decreased, presumably to counter the effect of the change in the fatty acid pattern. In host liver membranes, the diet-mediated increase in proportion of polyunsaturated fatty acids was not accompanied by an increase in the proportion of rigidifying saturated fatty acids. Instead, the homeoviscous adaptation consisted of decreases in monounsaturated fatty acids and cholesterol concentration and an increase in the phosphatidylethanolamine-phosphatidylcholine ratio. Addition of a natural inhibitor of cholesterol biosynthesis to the polyunsaturated fatty acid enriched-diet reversed the diet-mediated increase in the phosphatidylethanolamine-phosphatidylcholine ratio of host liver membranes. Tumor membrane lipids from hosts fed the combined dietary factors were characterized by the formentioned rigidifying increase in saturated fatty acids and compensatory decrease in the phosphatidylethanolamine-phosphatidylcholine ratio. The inhibitor reversed the compensatory increases in cholesterol and phospholipid phosphorus concentrations. As a consequence the thermosensitivity of tumors bearing this perturbed membrane was increased.
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Qureshi AA, Burger WC, Peterson DM, Elson C. Suppression of cholesterogenesis by plant constituents: review of Wisconsin contributions to NC-167. Lipids 1985; 20:817-24. [PMID: 4068910 DOI: 10.1007/bf02534407] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In animals, non-sterol metabolites of the mevalonate pathway act independently from receptor-mediated cholesterol uptake in the multivalent feedback regulation of mevalonate biosynthesis. Studies leading to the isolation and characterization of plant-borne suppressors of mevalonate biosynthesis are reviewed. We propose that one cardio-protective component of the vegetarian diet consists of a variety of non-sterol, post-mevalonate metabolites. These products of plant branches of the mevalonate pathway, discarded as animals evolved, continue to influence animal sterol metabolism. It is through this action, we propose, that the cholesterol-suppressive action of plant materials is expressed.
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Qureshi AA, Prentice N, Din ZZ, Burger WC, Elson CE, Sunde ML. Influence of culture filtrate of Trichoderma viride and barley on lipid metabolism of laying hens. Lipids 1984; 19:250-7. [PMID: 6538924 DOI: 10.1007/bf02534452] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The suppression of hepatic 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase and cholesterol 7 alpha-hydroxylase, previously noted in studies of the influences of barley and the filtrate of Trichoderma viride culture (CF) on cholesterol metabolism in sexually immature birds, is shown in sexually mature birds. Barley, CF or both were fed in one study from the day of hatching, in another during the period of sexual maturation and, in a third study, CF was fed to mature layers. CF suppressed HMG CoA reductase by 30-50% and cholesterol 7 alpha-hydroxylase by 32-45% when added to the control diet. In birds fed barley rather than corn, the respective activities were 25-36% and 24-31% lower. These effects were expressed in the lowering of plasma cholesterol by 11-36%. Lipogenic activity based on the assays of 4 enzymes was increased 2-3 times by the treatments and plasma triglyceride elevated by 12-86%. The start of egg production by birds fed CF preceded the controls by 17 days. Birds fed barley trailed controls by 11-14 days. CF countered the barley-conditioned delay. Egg yolk cholesterol concentrations were lowered by both treatments. Eggs produced by hens fed barley were lower in weight; CF increased egg and yolk weights. Tissues from birds fed CF or barley for up to 30 weeks appeared to be normal.
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Qureshi AA, Abuirmeileh N, Din ZZ, Ahmad Y, Burger WC, Elson CE. Suppression of cholesterogenesis and reduction of LDL cholesterol by dietary ginseng and its fractions in chicken liver. Atherosclerosis 1983; 48:81-94. [PMID: 6882511 DOI: 10.1016/0021-9150(83)90019-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The effects of ginseng root powder and of serially extracted solvent fractions of ginseng on avian hepatic cholesterol metabolism and lipogenesis and on avian serum lipoprotein cholesterol levels were examined. In one study, White Leghorn females were fed for 4 weeks a corn-based diet (control) or an experimental diet in which was incorporated 0.25% Wisconsin ginseng or an equivalent quantity of a serial solvent fraction [petroleum ether (PESF), methyl alcohol (MESF), water (WASF)] or of the residue. beta-hydroxy-beta-methylglutaryl-CoA (HMG-CoA) reductase activity was significantly lower (P less than 0.01) in each of the treatment groups (31-37% of control activity) except that fed the extracted residue (90% of control, N.S.). Cholesterol 7 alpha-hydroxylase activity was lowered in parallel (45-64% of control, P less than 0.01) by all treatments except the residue (100% of control). Also with the exception of the residue treatment, each ginseng treatment effected a lowering of the serum total cholesterol level (67-83% of control, P less than 0.01) and of serum low density lipoprotein cholesterol level (53-81% of control, P less than 0.01). Lipogenic activities and serum triglycerides levels were lowered (P less than 0.01) by two of the ginseng treatments. The PESF treatment was the most effective suppressor of each parameter, 74% and 68% respectively, of the control values. The WASF also had significant impact. Not one of the experimental diets influenced the serum high density lipoprotein level. The PESF, the potent source of suppressors, effected a change in the ratio of low to high density lipoprotein cholesterol from 1.46 (control) to 0.88. The levels of cholesterol and triglycerides in liver under these conditions showed a similar pattern as that of serum. In companion studies, broiler females were fed 0.28% Chinese red ginseng root powder or its various fractions. The results confirmed those recorded above. The factor(s) responsible for lowering the serum total and low density lipoprotein cholesterol levels were generally more concentrated in the PESF and WASF of ginseng and each was significantly more effective than was ginseng root powder. Ginsenosides (saponins) are considered to be the active agents for the suppression of cholesterogenesis and lipogenesis.
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Qureshi AA, Abuirmeileh N, Din ZZ, Elson CE, Burger WC. Inhibition of cholesterol and fatty acid biosynthesis in liver enzymes and chicken hepatocytes by polar fractions of garlic. Lipids 1983; 18:343-8. [PMID: 6877039 DOI: 10.1007/bf02537229] [Citation(s) in RCA: 97] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Different concentrations of polar fractions, methanol-soluble (MESF), or water-soluble (WASF), of 1-8% equivalent to fresh garlic paste were added to yellow corn-soybean based diets and fed to 5-week-old male broiler chickens for 3 weeks to measure the inhibition of hepatic beta-hydroxy-beta-methylglutaryl coenzyme A (HMG-CoA) reductase, cholesterol 7 alpha-hydroxylase (7 alpha-hydroxy) and fatty acid synthetase (FAS). Dose-related decreases in the activities of these enzymes were obtained. Decreases in serum total cholesterol and in low density lipoprotein (LDL) levels were also observed. There was no effect on the level of cholesterol in high density lipoprotein (HDL). The most effective dose for these decreases was found 0.54% (MESF) and 1.2% (WASF) equivalent to 6% of the fresh garlic. The inhibition of HMG-CoA reductase and FAS by 25-300 micrograms of MESF or WASF for 15 min was tested in vitro, in male and female chicken hepatocytes. Inhibitions of activity were dose-dependent and the degree of inhibition increased with duration of incubation (150 micrograms of MESF or WASF 5 to 60 min). Dietary supplementation of odorless WASF of garlic was found to be very effective in lowering the total and LDL cholesterol levels compared to control chickens.
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Burger WC, Qureshi AA, Prentice N, Elson CE. Effects of different fractions of the barley kernel on the hepatic lipid metabolism of chickens. Lipids 1982; 17:956-63. [PMID: 7162370 DOI: 10.1007/bf02534592] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Various physical fractions of the barley kernel were fed to one-day-old female and male chickens to determine their effect on hepatic beta-hydroxy-beta-methylglutaryl coenzyme A (HMG-CoA) reductase, cholesterol 7 alpha-hydroxylase and the lipogenic enzymes, acetyl-CoA carboxylase (ACX), malic enzyme (ME), citrate-cleavage enzyme (CCE) and fatty acid synthetase (FAS) at the subcellular level. Significant inhibition (p less than 0.01) of cholesterol biosynthesis accompanied by significant decreases in plasma cholesterol concentrations and induction of fatty acid synthesis were found in diets based on pearled barley, barley pearlings and a high-protein barley flour (HPBF: aleurone and subaleurone layers of barley endosperm) separated from the pearlings when compared to corn. Lower weight gains in 1- to 4-week-old birds fed the high-protein barley flour were found to be the result of lower feed consumption; pair feeding of 12-week-old birds with diets based on corn and high-protein barley flour produced equal weight gains in both treatments and significant reductions in hepatic HMG-CoA reductase, plasma cholesterol and induction in several lipogenic enzymes in birds fed the high-protein barley flour. Substitutions of 5-20% high-protein barley flour for corn in a corn-based diet produced significant weight gains (p less than 0.01) of 10 to 20% in 2-week-old chickens, inhibited cholesterol biosynthesis by 45-65% and produced a 3-fold increase in a fatty acid synthetase. The results indicate that HPBF contains an inhibitor(s) of cholesterol biosynthesis and a growth factor(s) when compared to a corn-based diet.
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