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Journal of Evolutionary Biology Apr 2020Dietary fatty acids can accumulate in sperm and affect their function in vertebrates. As Drosophila melanogaster shares several pathways of lipid metabolism and shows...
Dietary fatty acids can accumulate in sperm and affect their function in vertebrates. As Drosophila melanogaster shares several pathways of lipid metabolism and shows similar lipid-dependent phenotypes but lacks some hormones that in vertebrates regulate lipid metabolism, there is currently no clear prediction as to how dietary fatty acids affect the sperm of D. melanogaster. We manipulated the amount and identity of dietary polyunsaturated fatty acids (PUFA) in the food of D. melanogaster males (a treatment known to affect membrane fluidity) and measured changes in sperm parameters. We found that (a) males reared on food containing PUFA-rich, plant-derived lipids showed a slower increase in sperm volume over male age compared to males reared on yeast-derived lipid food which is richer in saturated fatty acids. (b) The resistance of sperm membrane integrity to osmotic stress was not altered by dietary lipid treatment, but (c) food containing yeast-derived lipids induced a 46% higher in situ rate of production of reactive oxygen species in sperm cells. These findings show that dietary lipids have similar effects on sperm parameters in Drosophila as in vertebrates, affect some, but not all, sperm parameters and modulate male reproductive ageing. In concert with recent findings of sex-specific seasonal variation of diet choice in the wild, our results suggest a substantial dietary impact on the dynamics of male reproduction in the wild.
Topics: Animals; Diet; Drosophila melanogaster; Fatty Acids, Unsaturated; Lipid Metabolism; Male; Reactive Oxygen Species; Spermatozoa; Sterols
PubMed: 31961473
DOI: 10.1111/jeb.13591 -
Annals of Nutrition & Metabolism 2009We elucidated the molecular mechanism(s) underlying sterol trafficking by investigating alterations in gene expression in response to increased retention of dietary...
BACKGROUND/AIMS
We elucidated the molecular mechanism(s) underlying sterol trafficking by investigating alterations in gene expression in response to increased retention of dietary phytosterols and phytostanols in stroke-prone spontaneously hypertensive (SHRSP) and normotensive Wistar Kyoto (WKY) inbred rats.
METHODS
SHRSP and WKY inbred rats were fed a control diet or a diet supplemented with phytosterols or phytostanols (2 g/kg diet).
RESULTS
Intake of phytosterols and phytostanols increased their incorporation in plasma, red blood cells, liver, aorta and kidney, but decreased cholesterol levels in liver and aorta in both rat strains. Phytosterol intake up-regulated mRNA expression of intestinal Npc1l1 and Abcg8, and hepatic Abcg5, Abca1, Cyp27a1 and Hmgcr. Phytostanol intake up-regulated Npc1l1 and Srebp2, but down-regulated Abcg5 mRNA expression in small intestine. Phytostanols also up-regulated Abca1 expression in SHRSP rats, but down-regulated Abca1 expression in WKY inbred rats. Compared to phytosterols, dietary phytostanols reduced phytosterol levels in plasma, red blood cells, and kidney, as well as altered mRNA levels of hepatic Abca1,Cyp27a1, and Hmgcr and intestinal Abcg5/8, Hmgcr and Srebp2.
CONCLUSIONS
Altered expression of multiple sterol-regulatory genes may contribute to the incorporation and cholesterol-lowering actions of phytosterols and phytostanols. Phytosterols and phytostanols may act through different mechanism(s) on cholesterol and phytosterol/phytostanol trafficking.
Topics: Animals; Anticholesteremic Agents; Cholestadienols; Cholesterol; Gene Expression Regulation; Hypolipidemic Agents; Jejunum; Liver; Male; Organ Specificity; Phytosterols; RNA, Messenger; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Sitosterols; Sterols
PubMed: 19851062
DOI: 10.1159/000252350 -
Nutrients May 2019Cardiovascular disease is a leading cause of death around the world. Overall diet quality and dietary behaviors are core contributors to metabolic health. While... (Review)
Review
Cardiovascular disease is a leading cause of death around the world. Overall diet quality and dietary behaviors are core contributors to metabolic health. While therapeutic targets have traditionally focused on levels of lipoprotein cholesterol when evaluating cardiovascular risk, current perspectives on high-density lipoprotein (HDL) have shifted to evaluating the functionality of this lipoprotein particle. Effects of diet on cardiovascular health are mediated through multiple pathways, but the impact on HDL composition and function deserves greater attention. Potential areas of investigation involve changes in particle characteristics, distribution, microRNA cargo, and other functional changes such as improvements to cholesterol efflux capacity. Various dietary patterns like the Mediterranean diet and Dietary Approaches to Stop Hypertension (DASH) diet have beneficial effects on cardiovascular health and may prevent cardiovascular events. These healthful dietary patterns tend to be rich in plant-based foods, with cardiovascular benefits likely resulting from synergistic effects of the individual dietary components. The purpose of this review is to summarize current perspectives on selected functions of HDL particles and how various dietary patterns affect cardiovascular health biomarkers, with a focus on HDL functionality.
Topics: Cardiovascular Physiological Phenomena; Cholesterol, HDL; Diet, Mediterranean; Dietary Approaches To Stop Hypertension; Humans
PubMed: 31151202
DOI: 10.3390/nu11061231 -
The Journal of Clinical Investigation Dec 1998Feedback regulation of cholesterol biosynthesis is mediated by membrane-bound transcription factors designated sterol regulatory element-binding proteins (SREBP)-1 and...
Feedback regulation of cholesterol biosynthesis is mediated by membrane-bound transcription factors designated sterol regulatory element-binding proteins (SREBP)-1 and -2. In sterol-deprived cultured cells, SREBPs are released from membranes by a proteolytic process that is stimulated by SREBP cleavage-activating protein (SCAP), a membrane protein containing a sterol-sensing domain. Sterols suppress SREBP cleavage by blocking the action of SCAP, thereby decreasing cholesterol synthesis. A point mutation in SCAP(D443N) causes resistance to sterol suppression. In this article, we produced transgenic mice that express mutant SCAP(D443N) in liver. In these livers the nuclear content of SREBP-1 and -2 was increased, mRNAs encoding proteins involved in uptake and synthesis of cholesterol and fatty acids were elevated, and the livers were engorged with cholesteryl esters and triglycerides enriched in monounsaturated fatty acids. When the mice were challenged with a high cholesterol diet, cleavage of SREBP-1 and -2 was reduced in wild-type livers and less so in transgenic livers. We conclude that SCAP(D443N) stimulates proteolytic processing of native SREBPs in liver and decreases the normal sterol-mediated feedback regulation of SREBP cleavage, suggesting a central role for SCAP as a sterol sensor in liver.
Topics: Animals; CCAAT-Enhancer-Binding Proteins; Cholesterol; DNA-Binding Proteins; Diet; Fatty Acids; Feedback; Intracellular Signaling Peptides and Proteins; Lipid Metabolism; Liver; Membrane Proteins; Mice; Mice, Transgenic; Mutation; Nuclear Proteins; Phenotype; RNA, Messenger; Stearoyl-CoA Desaturase; Sterol Regulatory Element Binding Protein 1; Sterol Regulatory Element Binding Protein 2; Sterols; Transcription Factors
PubMed: 9854040
DOI: 10.1172/JCI5341 -
The American Journal of Cardiology Jul 2005Normal serum contains small amounts of noncholesterol sterols, including those reflecting cholesterol absorption and those that are markers of cholesterol synthesis.... (Review)
Review
Normal serum contains small amounts of noncholesterol sterols, including those reflecting cholesterol absorption and those that are markers of cholesterol synthesis. Absorption marker sterols include serum plant sterols, whereas cholesterol precursor sterols correlate with whole-body synthesis of cholesterol. Thus, serum noncholesterol sterols, and especially their ratios to cholesterol, can be used to evaluate the major features of cholesterol metabolism (ie, synthesis and absorption). Statin treatment reduces serum cholesterol precursors but increases serum plant sterols severalfold, especially in subjects with high-absorption marker sterol levels indicative of efficient cholesterol and sterol absorption in general. Statin therapy is most effective in subjects with high serum cholesterol precursor levels. In subjects with high-absorption sterol markers, dietary cholesterol absorption inhibition (eg, with plant stanol and sterol ester margarine) needs to be combined with a statin to achieve effective serum cholesterol reduction. However, whereas dietary plant stanol esters reduce statin-induced elevations of serum plant sterol levels, serum plant sterol levels remain elevated during dietary plant sterol ester consumption. The clinical implication of high serum plant sterol levels is under active investigation.
Topics: Cholesterol, LDL; Diet; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Hypercholesterolemia; Intestinal Absorption; Phytosterols; Sitosterols
PubMed: 15992515
DOI: 10.1016/j.amjcard.2005.03.019 -
Nutrition Journal Jul 2023The potential role of dietary branched-chain amino acids (BCAA) in metabolic health, including cardiovascular disease and diabetes, is evolving, and it is yet to be...
BACKGROUND
The potential role of dietary branched-chain amino acids (BCAA) in metabolic health, including cardiovascular disease and diabetes, is evolving, and it is yet to be understood if dietary BCAA intakes are associated with plasma lipid profiles or dyslipidaemia. This study tested the association of dietary BCAA intakes with plasma lipid profiles and dyslipidaemia among Filipino women in Korea.
METHODS
Energy-adjusted dietary BCAA intakes (isoleucine, leucine, valine, and total BCAA) and fasting blood profiles of triglycerides (TG), total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), and low-density lipoprotein-cholesterol (LDL-C) were determined in a sample of 423 women enrolled in the Filipino Women's Diet and Health Study (FiLWHEL). The generalized linear model was applied to estimate least-square (LS) means and 95% confidence intervals (CIs) and compare plasma TG, TC, HDL-C, and LDL-C across tertile distribution of energy-adjusted dietary BCAA intakes at P < 0.05.
RESULTS
Mean of energy-adjusted dietary total BCAA intake was 8.3 ± 3.9 g/d. Average plasma lipid profiles were 88.5 ± 47.4 mg/dl for TG, 179.7 ± 34.5 mg/dl for TC, 58.0 ± 13.7 mg/dl for HDL-C, and 104.0 ± 30.5 mg/dl for LDL-C. LS means, and 95% CIs across tertiles of energy-adjusted total BCAA intakes were 89.9 mg/dl, 88.8 mg/dl and 85.8 mg/dl (P-trend = 0.45) for TG, 179.1 mg/dl, 183.6 mg/dl and 176.5 mg/dl (P-trend = 0.48) for TC, 57.5 mg/dl, 59.6 mg/dl and 57.1 mg/dl (P-trend = 0.75) for HDL-C and 103.6 mg/dl, 106.2 mg/dl and 102.3 mg/dl (P-trend = 0.68) for LDL-C. Furthermore, the multivariable-adjusted prevalence ratios and 95% confidence intervals for dyslipidaemia across increasing tertile distribution of energy-adjusted total BCAA intake were; 1.00, 0.67 (0.40, 1.13) and 0.45 (0.16, 1.27; P-trend = 0.03) for the first, second and third tertile, respectively.
CONCLUSIONS
Higher dietary intakes of BCAA presented a statistically significant inverse trend with the prevalence of dyslipidaemia among Filipino women in this study and testing these associations in longitudinal studies may be necessary to confirm these findings.
Topics: Female; Humans; Amino Acids, Branched-Chain; Cholesterol, LDL; Diet; Cholesterol, HDL; Eating; Republic of Korea
PubMed: 37430285
DOI: 10.1186/s12937-023-00861-w -
Lipids Jul 2012This study investigated the effect of two partially hydrolyzed guar gums (PHGG) on fatty acid and sterol excretion. PHGG were obtained by chemical hydrolysis of guar gum...
This study investigated the effect of two partially hydrolyzed guar gums (PHGG) on fatty acid and sterol excretion. PHGG were obtained by chemical hydrolysis of guar gum (GG) with H(2)O:EtOH (1:1) at 100 °C for 1 h (PHGG1) or 2 h (PHGG2). The viscosity of the PHGG in a 1 % (w/v) aqueous solution corresponded to that of a pseudoplastic fluid and was higher for PHGG1 than PHGG2. Guinea pigs (n = 8 per group) were fed high fat diets (17/100 g) that contained 12/100 g of cellulose, PHGG1, or PHGG2 for 4 weeks. Despite the differences in viscosity, the two PHGG exerted similar physiological effects. Compared to the control cellulose group, the body weight gain was lower in animals fed PHGG, although no effect on food consumption was observed. PHGG increased the excretion of fatty acids and neutral sterols, but not bile acids. Consumption of PHGG did not alter the fecal fatty acid profile, while intestinal bioconversion of sterols tended to increase in response to PHGG2. A reduction in the viscosity within the range tested did not correlate with losses in the hypocholesterolemic capacity of PHGG as both were effective in reducing plasma cholesterol. Thus, we conclude that the chemical hydrolysis of guar gum renders the gum suitable for inclusion in food products without significantly altering its beneficial health effects.
Topics: Animals; Bile Acids and Salts; Diet, High-Fat; Dietary Fiber; Fatty Acids; Female; Galactans; Guinea Pigs; Lipid Metabolism; Mannans; Plant Gums; Sterols; Viscosity
PubMed: 22669591
DOI: 10.1007/s11745-012-3682-1 -
Life Sciences 1995Most animal and human studies show that phytosterols reduce serum/or plasma total cholesterol and low density lipoprotein (LDL) cholesterol levels. Phytosterols are... (Review)
Review
Most animal and human studies show that phytosterols reduce serum/or plasma total cholesterol and low density lipoprotein (LDL) cholesterol levels. Phytosterols are structurally very similar to cholesterol except that they always contain some substitutions at the C24 position on the sterol side chain. Plasma phytosterol levels in mammalian tissue are normally very low due primarily to poor absorption from the intestine and faster excretion from liver compared to cholesterol. Phytosterols are able to be metabolized in the liver into C21 bile acids via liver other than normal C24 bile acids in mammals. It is generally assumed that cholesterol reduction results directly from inhibition of cholesterol absorption through displacement of cholesterol from micelles. Structure-specific effects of individual phytosterol constituents have recently been shown where saturated phytosterols are more efficient compared to unsaturated compounds in reducing cholesterol levels. In addition, phytosterols produce a wide spectrum of therapeutic effects in animals including anti-tumour properties. Phytosterols have been shown experimentally to inhibit colon cancer development. With regard to toxicity, no obvious side effects of phytosterol have been observed in studies to date, except in individual with phytosterolemia, an inherited lipid disorder. Further characterization of the influence of various phytosterol subcomponents on lipoprotein profiles in humans is required to maximize the usefulness of this non-pharmacological approach to reduction of atherosclerosis in the population.
Topics: Animals; Antineoplastic Agents; Cholesterol; Diet; Humans; Intestinal Absorption; Lipoproteins; Phytosterols; Sterol O-Acyltransferase
PubMed: 7596226
DOI: 10.1016/0024-3205(95)00263-6 -
Nutrition in Clinical Practice :... Feb 1992The role of molecular biology in understanding structure/function relationships as well as the influence of metabolic processes on host nutrition is becoming... (Review)
Review
The role of molecular biology in understanding structure/function relationships as well as the influence of metabolic processes on host nutrition is becoming increasingly important. Not only is this field having a major effect in elucidating the detailed structure of nutritionally important enzymes but it is also allowing the nutrition scientist to study metabolic function and the significance of different pathways in whole animals. In this review, the use of gene transfer studies, in particular, the creation of transgenic animals to study mechanisms in which nutrients may regulate gene expression is discussed. Although these studies are presently quite specific, it is envisioned that these studies will ultimately lead to a better understanding of dietary host interactions, which may lead to the ability of the clinician to optimize dietary intake in order to more favorably modify metabolic disorders.
Topics: Cholesterol; Diet; Energy Intake; Gene Expression; Humans; Molecular Biology; Nutritional Physiological Phenomena; Transcription, Genetic
PubMed: 1293498
DOI: 10.1177/011542659200700116 -
Food & Function Nov 2021Cholesterol gallstone disease is a common global condition. This study investigated the role of plant sterols (PS) in the prevention of gallstone formation and the...
Cholesterol gallstone disease is a common global condition. This study investigated the role of plant sterols (PS) in the prevention of gallstone formation and the underlying mechanisms. Adult male mice were fed a lithogenic diet (LD) alone or supplemented with PS (LD-ps), phospholipids (LD-pl) or both PS and phospholipids (LD-ps/pl) for 8 weeks. Incidences of gallstone formation were compared among the groups. Lipids in the bile, liver and serum were analyzed. The expression of genes involved in cholesterol absorption, transport and metabolism in the liver and small intestine was determined. The incidences of gallstone formation were 100% (10/10), 20% (2/10), 100% (10/10) and 40% (4/10) in the LD, LD-ps, LD-pl and LD-ps/pl groups, respectively. Serum cholesterol and intestinal cholesterol absorption were decreased in PS-supplemented mice. The expression of genes related to cholesterol transport and metabolism in the liver was down-regulated by dietary PS. PS supplementation decreased Niemann-Pick C1-like 1 expression in the small intestine and reduced intestinal cholesterol absorption. Our results demonstrated that PS could inhibit intestinal cholesterol absorption and thus prevent cholesterol gallstone formation.
Topics: Animals; Cholesterol; Diet; Dietary Supplements; Gallstones; Intestinal Absorption; Male; Mice; Mice, Inbred C57BL; Phytosterols
PubMed: 34787152
DOI: 10.1039/d1fo02695j