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Lewis GF, Mulvihill EE. The Complexities of Intestinal Lipoprotein Production in Insulin Resistance and Diabetes: Revisiting a 2010 Diabetes Classic by Pavlic et al. Diabetes 2024; 73:335-337. [PMID: 38377446 DOI: 10.2337/dbi23-0036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 12/19/2023] [Indexed: 02/22/2024]
Affiliation(s)
- Gary F Lewis
- Department of Medicine and Department of Physiology, University of Toronto, Toronto, Ontario, Canada
- Division of Endocrinology and Metabolism, University of Toronto, Toronto, Ontario, Canada
| | - Erin E Mulvihill
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
- University of Ottawa Heart Institute, Ottawa, Ontario, Canada
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2
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Fourati S, Hamon A, Daclat R, Salem JE, Peoc’h K, Le Beyec J, Joly F, Lacorte JM. Circulating Apolipoprotein B-48 as a Biomarker of Parenteral Nutrition Dependence in Adult Patients with Short Bowel Syndrome. Nutrients 2023; 15:3982. [PMID: 37764766 PMCID: PMC10536633 DOI: 10.3390/nu15183982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 09/05/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Short bowel syndrome (SBS) is a rare but serious condition that may lead to chronic intestinal failure. Citrulline concentrations are currently used to reflect the residual intestinal mass in patients with SBS, although this method has several limitations. In a cohort of patients with SBS, we quantified apolipoprotein B-48 (ApoB-48), which is exclusively synthesized by enterocytes and secreted associated with dietary lipids and investigated the relationship between ApoB-48 and clinical and biological data as well as PN dependence. A total of 51 adult patients were included, 36 of whom were PN-dependent. We found a robust positive correlation between circulating ApoB-48 and residual small bowel length, which was also found in the subgroup of patients with jejunocolic anastomosis. Fasting ApoB-48 levels were significantly lower in PN-dependent patients than in PN-weaned patients and negatively correlated with parenteral nutrition dependence. Our results suggest that ApoB-48 could be proposed as a marker of intestinal absorptive function and could be an interesting follow-up marker in patients with SBS.
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Affiliation(s)
- Salma Fourati
- Service de Biochimie Endocrinienne et Oncologique, Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, UMR-S 1149 Centre de Recherche sur l’Inflammation Inserm, Paris Cité University, 75013 Paris, France
| | - Annick Hamon
- Department of Gastroenterology, IBD and Nutrition Support, CRMR MarDi, Beaujon Hospital, Assistance Publique-Hôpitaux de Paris, 92110 Clichy, France
| | - Rita Daclat
- UMR_S1166, Research Institute of Cardiovascular Disease, Metabolism and Nutrition Inserm, Pitié-Salpêtrière Hospital, Sorbonne University, 75013 Paris, France
| | - Joe-Elie Salem
- Department of Pharmacology and Clinical Investigation Centre (CIC-1901), Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, Sorbonne University, INSERM, 75013 Paris, France
| | - Katell Peoc’h
- Department of Biochemistry, CRI INSERM UMR1149, HUPNVS, Assistance Publique-Hôpitaux de Paris, Paris Cité University, 75018 Paris, France
| | - Johanne Le Beyec
- Service de Biochimie Endocrinienne et Oncologique, Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, UMR-S 1149 Centre de Recherche sur l’Inflammation Inserm, Sorbonne University, 75013 Paris, France;
| | - Francisca Joly
- Department of Gastroenterology, IBD and Nutrition Support, CRMR MarDi, Beaujon Hospital, Assistance Publique-Hôpitaux de Paris, 92110 Clichy, UMR-S 1149 Centre de Recherche sur l’Inflammation Inserm, Université Paris Cité, 75018 Paris, France;
| | - Jean-Marc Lacorte
- Service de Biochimie Endocrinienne et Oncologique, Pitié-Salpêtrière Hospital, Assistance Publique-Hôpitaux de Paris, Research Unit on Cardiovascular and Metabolic Disease, UMR ICAN, Sorbonne University, Inserm, 75013 Paris, France;
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Zhang W, Zhao Y, He Q, Lang R. Therapeutically targeting essential metabolites to improve immunometabolism manipulation after liver transplantation for hepatocellular carcinoma. Front Immunol 2023; 14:1211126. [PMID: 37492564 PMCID: PMC10363744 DOI: 10.3389/fimmu.2023.1211126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 06/26/2023] [Indexed: 07/27/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is the most prevalent primary liver malignancy worldwide and is associated with a poor prognosis. Sophisticated molecular mechanisms and biological characteristics need to be explored to gain a better understanding of HCC. The role of metabolites in cancer immunometabolism has been widely recognized as a hallmark of cancer in the tumor microenvironment (TME). Recent studies have focused on metabolites that are derived from carbohydrate, lipid, and protein metabolism, because alterations in these may contribute to HCC progression, ischemia-reperfusion (IR) injury during liver transplantation (LT), and post-LT rejection. Immune cells play a central role in the HCC microenvironment and the duration of IR or rejection. They shape immune responses through metabolite modifications and by engaging in complex crosstalk with tumor cells. A growing number of publications suggest that immune cell functions in the TME are closely linked to metabolic changes. In this review, we summarize recent findings on the primary metabolites in the TME and post-LT metabolism and relate these studies to HCC development, IR injury, and post-LT rejection. Our understanding of aberrant metabolism and metabolite targeting based on regulatory metabolic pathways may provide a novel strategy to enhance immunometabolism manipulation by reprogramming cell metabolism.
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Affiliation(s)
- Wenhui Zhang
- Department of Hepatobiliary Surgery, Beijing Chao-Yang Hospital Affiliated to Capital Medical University, Beijing, China
| | - Yu Zhao
- Department of Urology Surgery, Beijing Chao-Yang Hospital Affiliated to Capital Medical University, Beijing, China
| | - Qiang He
- Department of Hepatobiliary Surgery, Beijing Chao-Yang Hospital Affiliated to Capital Medical University, Beijing, China
| | - Ren Lang
- Department of Hepatobiliary Surgery, Beijing Chao-Yang Hospital Affiliated to Capital Medical University, Beijing, China
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A mixed blessing for liver transplantation patients - Rapamycin. Hepatobiliary Pancreat Dis Int 2023; 22:14-21. [PMID: 36328894 DOI: 10.1016/j.hbpd.2022.10.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 10/14/2022] [Indexed: 11/04/2022]
Abstract
BACKGROUND Liver transplantation (LT) is an effective treatment option for end-stage liver disease. Mammalian target of rapamycin (mTOR) inhibitors, such as rapamycin, are widely used post LT. DATA SOURCES In this review, we focused on the anti-cancer activities and metabolic side effects of rapamycin after LT. The literature available on PubMed for the period of January 1999-September 2022 was reviewed. The key words were rapamycin, sirolimus, liver transplantation, hepatocellular carcinoma, diabetes, and lipid metabolism disorder. RESULTS Rapamycin has shown excellent effects and is safer than other immunosuppressive regimens. It has exhibited excellent anti-cancer activity and has the potential in preventing hepatocellular carcinoma (HCC) recurrence post LT. Rapamycin is closely related to two long-term complications after LT, diabetes and lipid metabolism disorders. CONCLUSIONS Rapamycin prevents HCC recurrence post LT in some patients, but it also induces metabolic disorders. Reasonable use of rapamycin benefits the liver recipients.
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Cook JR, Kohan AB, Haeusler RA. An Updated Perspective on the Dual-Track Model of Enterocyte Fat Metabolism. J Lipid Res 2022; 63:100278. [PMID: 36100090 PMCID: PMC9593242 DOI: 10.1016/j.jlr.2022.100278] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 08/08/2022] [Accepted: 08/31/2022] [Indexed: 02/04/2023] Open
Abstract
The small intestinal epithelium has classically been envisioned as a conduit for nutrient absorption, but appreciation is growing for a larger and more dynamic role for enterocytes in lipid metabolism. Considerable gaps remain in our knowledge of this physiology, but it appears that the enterocyte's structural polarization dictates its behavior in fat partitioning, treating fat differently based on its absorption across the apical versus the basolateral membrane. In this review, we synthesize existing data and thought on this dual-track model of enterocyte fat metabolism through the lens of human integrative physiology. The apical track includes the canonical pathway of dietary lipid absorption across the apical brush-border membrane, leading to packaging and secretion of those lipids as chylomicrons. However, this track also reserves a portion of dietary lipid within cytoplasmic lipid droplets for later uses, including the "second-meal effect," which remains poorly understood. At the same time, the enterocyte takes up circulating fats across the basolateral membrane by mechanisms that may include receptor-mediated import of triglyceride-rich lipoproteins or their remnants, local hydrolysis and internalization of free fatty acids, or enterocyte de novo lipogenesis using basolaterally absorbed substrates. The ultimate destinations of basolateral-track fat may include fatty acid oxidation, structural lipid synthesis, storage in cytoplasmic lipid droplets, or ultimate resecretion, although the regulation and purposes of this basolateral track remain mysterious. We propose that the enterocyte integrates lipid flux along both of these tracks in order to calibrate its overall program of lipid metabolism.
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Affiliation(s)
- Joshua R. Cook
- Naomi Berrie Diabetes Center, Columbia University College of Physicians and Surgeons, New York, NY, USA,Division of Endocrinology, Diabetes & Metabolism, Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA
| | - Alison B. Kohan
- Division of Endocrinology and Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Rebecca A. Haeusler
- Naomi Berrie Diabetes Center, Columbia University College of Physicians and Surgeons, New York, NY, USA,Department of Pathology and Cell Biology; Columbia University College of Physicians and Surgeons, New York, NY, USA,For correspondence: Rebecca A. Haeusler
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6
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Stahel P, Xiao C, Nahmias A, Tian L, Lewis GF. Multi-organ Coordination of Lipoprotein Secretion by Hormones, Nutrients and Neural Networks. Endocr Rev 2021; 42:815-838. [PMID: 33743013 PMCID: PMC8599201 DOI: 10.1210/endrev/bnab008] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Indexed: 12/15/2022]
Abstract
Plasma triglyceride-rich lipoproteins (TRL), particularly atherogenic remnant lipoproteins, contribute to atherosclerotic cardiovascular disease. Hypertriglyceridemia may arise in part from hypersecretion of TRLs by the liver and intestine. Here we focus on the complex network of hormonal, nutritional, and neuronal interorgan communication that regulates secretion of TRLs and provide our perspective on the relative importance of these factors. Hormones and peptides originating from the pancreas (insulin, glucagon), gut [glucagon-like peptide 1 (GLP-1) and 2 (GLP-2), ghrelin, cholecystokinin (CCK), peptide YY], adipose tissue (leptin, adiponectin) and brain (GLP-1) modulate TRL secretion by receptor-mediated responses and indirectly via neural networks. In addition, the gut microbiome and bile acids influence lipoprotein secretion in humans and animal models. Several nutritional factors modulate hepatic lipoprotein secretion through effects on the central nervous system. Vagal afferent signaling from the gut to the brain and efferent signals from the brain to the liver and gut are modulated by hormonal and nutritional factors to influence TRL secretion. Some of these factors have been extensively studied and shown to have robust regulatory effects whereas others are "emerging" regulators, whose significance remains to be determined. The quantitative importance of these factors relative to one another and relative to the key regulatory role of lipid availability remains largely unknown. Our understanding of the complex interorgan regulation of TRL secretion is rapidly evolving to appreciate the extensive hormonal, nutritional, and neural signals emanating not only from gut and liver but also from the brain, pancreas, and adipose tissue.
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Affiliation(s)
- Priska Stahel
- Division of Endocrinology and Metabolism, Departments of Medicine and Physiology, Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Changting Xiao
- Department of Anatomy, Physiology and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Avital Nahmias
- Division of Endocrinology and Metabolism, Departments of Medicine and Physiology, Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Lili Tian
- Division of Endocrinology and Metabolism, Departments of Medicine and Physiology, Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Gary Franklin Lewis
- Division of Endocrinology and Metabolism, Departments of Medicine and Physiology, Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
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Maraninchi M, Calabrese A, Nogueira JP, Castinetti F, Mancini J, Mourre F, Piétri L, Bénamo E, Albarel F, Morange I, Dupont-Roussel J, Nicolay A, Brue T, Béliard S, Valéro R. Role of growth hormone in hepatic and intestinal triglyceride-rich lipoprotein metabolism. J Clin Lipidol 2021; 15:712-723. [PMID: 34462238 DOI: 10.1016/j.jacl.2021.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 07/23/2021] [Accepted: 08/09/2021] [Indexed: 11/16/2022]
Abstract
BACKGROUND Elevated plasma concentrations of hepatic- and intestinally-derived triglyceride-rich lipoproteins (TRL) are implicated in the pathogenesis of atherosclerotic cardiovascular disease and all-cause mortality. Excess of TRL is the driving cause of atherogenic dyslipidemia commonly occurring in insulin-resistant individuals such as patients with obesity, type 2 diabetes and metabolic syndrome. Interestingly, growth hormone (GH)-deficient individuals display similar atherogenic dyslipidemia, suggesting an important role of GH and GH deficiency in the regulation of TRL metabolism. OBJECTIVE We aimed to examine the direct and/or indirect role of GH on TRL metabolism. METHODS We investigated the effect on fasting and postprandial hepatic-TRL and intestinal-TRL metabolism of short-term (one month) withdrawal of GH in 10 GH-deficient adults. RESULTS After GH withdrawal, we found a reduction in fasting plasma TRL concentration (significant decrease in TRL-TG, TRL-cholesterol, TRL-apoB-100, TRL-apoC-III and TRL-apoC-II) but not in postprandial TRL response. This reduction was due to fewer fasting TRL particles without a change in TG per particle and was not accompanied by a change in postprandial TRL-apoB-48 response. Individual reductions in TRL correlated strongly with increases in insulin sensitivity and decreases in TRL-apoC-III. CONCLUSION In this relatively short term 'loss of function' human experimental model, we have shown an unanticipated reduction of hepatic-TRL particles despite increase in total body fat mass and reduction in lean mass. These findings contrast with the atherogenic dyslipidemia previously described in chronic GH deficient states, providing a new perspective for the role of GH in lipoprotein metabolism.
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Affiliation(s)
- Marie Maraninchi
- Aix Marseille Univ, APHM, INSERM, INRAE, C2VN, University Hospital La Conception, Department of Nutrition, Metabolic Diseases and Endocrinology, 147 boulevard Baille, Marseille 13005, France
| | - Anastasia Calabrese
- Aix Marseille Univ, APHM, INSERM, INRAE, C2VN, University Hospital La Conception, Department of Nutrition, Metabolic Diseases and Endocrinology, 147 boulevard Baille, Marseille 13005, France
| | - Juan-Patricio Nogueira
- Docencia e Investigacion, Hospital Central de Formosa, Salta 555, Formosa CP 3600, Argentina; Facultad de Ciencias de la Salud, Universidad Nacional de Formosa, Gutnisky 3200, Formosa CP 3600, Argentina
| | - Frédéric Castinetti
- INSERM, U1251, Marseille Medical Genetics (MMG), Faculté des Sciences médicales et paramédicales, France and AP-HM, Department of Endocrinology, Hôpital de la Conception, Centre de Référence des Maladies Rares de l'hypophyse HYPO, Institut Marseille Maladies Rares (MarMaRa), Aix-Marseille Univ, Marseille 13005, France
| | - Julien Mancini
- INSERM, IRD, UMR1252, SESSTIM, Aix-Marseille Univ, Marseille F-13273, France; APHM, Timone Hospital, Public Health Department (BIOSTIC), Marseille, F-13385, France
| | - Florian Mourre
- Aix Marseille Univ, APHM, INSERM, INRAE, C2VN, University Hospital La Conception, Department of Nutrition, Metabolic Diseases and Endocrinology, 147 boulevard Baille, Marseille 13005, France
| | - Léa Piétri
- Aix Marseille Univ, APHM, INSERM, INRAE, C2VN, University Hospital La Conception, Department of Nutrition, Metabolic Diseases and Endocrinology, 147 boulevard Baille, Marseille 13005, France
| | - Eric Bénamo
- Department of Endocrinology and Metabolic Diseases, Hospital d'Avignon Henri Duffaut, 205 rue Raoul Follereau, Avignon 84000, France
| | - Frédérique Albarel
- INSERM, U1251, Marseille Medical Genetics (MMG), Faculté des Sciences médicales et paramédicales, France and AP-HM, Department of Endocrinology, Hôpital de la Conception, Centre de Référence des Maladies Rares de l'hypophyse HYPO, Institut Marseille Maladies Rares (MarMaRa), Aix-Marseille Univ, Marseille 13005, France
| | - Isabelle Morange
- INSERM, U1251, Marseille Medical Genetics (MMG), Faculté des Sciences médicales et paramédicales, France and AP-HM, Department of Endocrinology, Hôpital de la Conception, Centre de Référence des Maladies Rares de l'hypophyse HYPO, Institut Marseille Maladies Rares (MarMaRa), Aix-Marseille Univ, Marseille 13005, France
| | - Jeanine Dupont-Roussel
- Aix Marseille Univ, APHM, INSERM, INRAE, C2VN, University Hospital La Conception, Department of Nutrition, Metabolic Diseases and Endocrinology, 147 boulevard Baille, Marseille 13005, France
| | - Alain Nicolay
- APHM, Laboratory of Endocrine Biochemistry, La Conception Hospital, Marseille, France
| | - Thierry Brue
- INSERM, U1251, Marseille Medical Genetics (MMG), Faculté des Sciences médicales et paramédicales, France and AP-HM, Department of Endocrinology, Hôpital de la Conception, Centre de Référence des Maladies Rares de l'hypophyse HYPO, Institut Marseille Maladies Rares (MarMaRa), Aix-Marseille Univ, Marseille 13005, France
| | - Sophie Béliard
- Aix Marseille Univ, APHM, INSERM, INRAE, C2VN, University Hospital La Conception, Department of Nutrition, Metabolic Diseases and Endocrinology, 147 boulevard Baille, Marseille 13005, France
| | - René Valéro
- Aix Marseille Univ, APHM, INSERM, INRAE, C2VN, University Hospital La Conception, Department of Nutrition, Metabolic Diseases and Endocrinology, 147 boulevard Baille, Marseille 13005, France.
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Jacome-Sosa M, Hu Q, Manrique-Acevedo CM, Phair RD, Parks EJ. Human intestinal lipid storage through sequential meals reveals faster dinner appearance is associated with hyperlipidemia. JCI Insight 2021; 6:e148378. [PMID: 34369385 PMCID: PMC8489663 DOI: 10.1172/jci.insight.148378] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 06/30/2021] [Indexed: 12/14/2022] Open
Abstract
Background It is increasingly recognized that intestinal cells can store lipids after a meal, yet the effect of this phenomenon on lipid absorption patterns in insulin resistance remains unknown. Methods The kinetics of meal fat appearance were measured in insulin-sensitive (IS, n = 8) and insulin-resistant (IR, n = 8) subjects after sequential, isotopically labeled lunch and dinner meals. Plasma dynamics on triacylglycerol-rich (TAG-rich) lipoproteins and plasma hormones were analyzed using a nonlinear, non–steady state kinetic model. Results At the onset of dinner, IS subjects showed an abrupt plasma appearance of lunch lipid consistent with the “second-meal effect,” followed by slower appearance of dinner fat in plasma, resulting in reduced accumulation of dinner TAG of 48% compared with lunch. By contrast, IR subjects exhibited faster meal TAG appearance rates after both lunch and dinner. This effect of lower enterocyte storage between meals was associated with greater nocturnal and next-morning hyperlipidemia. The biochemical data and the kinetic analysis of second-meal effect dynamics are consistent with rapid secretion of stored TAG bypassing lipolysis and resynthesis. In addition, the data are consistent with a role for the diurnal pattern of plasma leptin in regulating the processing of dietary lipid. Conclusion These data support the concept that intestinal lipid storage may be physiologically beneficial in IS subjects. Trial registration ClinicalTrials.gov NCT02020343. Funding This study was supported by a grant from the American Diabetes Association (grant 1-13-TS-12).
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Affiliation(s)
| | - Qiong Hu
- Department of Nutrition and Exercise Physiology and
| | | | - Robert D Phair
- Integrative Bioinformatics, Inc., Mountain View, California, USA
| | - Elizabeth J Parks
- Department of Nutrition and Exercise Physiology and.,Division of Gastroenterology and Hepatology, School of Medicine, University of Missouri, Columbia, Missouri, USA
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Dilworth L, Facey A, Omoruyi F. Diabetes Mellitus and Its Metabolic Complications: The Role of Adipose Tissues. Int J Mol Sci 2021; 22:ijms22147644. [PMID: 34299261 PMCID: PMC8305176 DOI: 10.3390/ijms22147644] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/08/2021] [Accepted: 07/12/2021] [Indexed: 12/14/2022] Open
Abstract
Many approaches have been used in the effective management of type 2 diabetes mellitus. A recent paradigm shift has focused on the role of adipose tissues in the development and treatment of the disease. Brown adipose tissues (BAT) and white adipose tissues (WAT) are the two main types of adipose tissues with beige subsets more recently identified. They play key roles in communication and insulin sensitivity. However, WAT has been shown to contribute significantly to endocrine function. WAT produces hormones and cytokines, collectively called adipocytokines, such as leptin and adiponectin. These adipocytokines have been proven to vary in conditions, such as metabolic dysfunction, type 2 diabetes, or inflammation. The regulation of fat storage, energy metabolism, satiety, and insulin release are all features of adipose tissues. As such, they are indicators that may provide insights on the development of metabolic dysfunction or type 2 diabetes and can be considered routes for therapeutic considerations. The essential roles of adipocytokines vis-a-vis satiety, appetite, regulation of fat storage and energy, glucose tolerance, and insulin release, solidifies adipose tissue role in the development and pathogenesis of diabetes mellitus and the complications associated with the disease.
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Affiliation(s)
- Lowell Dilworth
- Department of Pathology, Mona Campus, University of the West Indies, Kingston 7, Jamaica;
| | - Aldeam Facey
- Mona Academy of Sport, Mona Campus, University of the West Indies, Kingston 7, Jamaica;
| | - Felix Omoruyi
- Department of Life Sciences, Texas A&M University, Corpus Christi, TX 78412, USA
- Correspondence:
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Higgins V, Adeli K. Postprandial dyslipidemia in insulin resistant states in adolescent populations. J Biomed Res 2020; 34:328-342. [PMID: 32934193 PMCID: PMC7540238 DOI: 10.7555/jbr.34.20190094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 11/13/2019] [Indexed: 02/06/2023] Open
Abstract
Obesity and the metabolic syndrome are becoming increasingly prevalent not only in adults, but also in adolescents. The metabolic syndrome, a complex cluster of metabolic abnormalities, increases one's risk of developing type 2 diabetes and cardiovascular disease (CVD). Dyslipidemia, a key component of the metabolic syndrome, is highly associated with insulin resistance and contributes to increased CVD risk. Dyslipidemia has traditionally been assessed using a fasting lipid profile [i.e. fasting triglycerides, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C)]. However, the postprandial state predominates over the course of a day and non-fasting triglycerides independently predict CVD risk. In insulin resistant states, the intestine overproduces triglyceride-rich lipoprotein (TRL) particles, termed chylomicrons (CMs), following ingestion of a fat-containing meal, as well as in the fasting state. Along with elevated hepatic TRLs (i.e. very-low density lipoproteins), CMs contribute to remnant lipoprotein accumulation, small dense LDL particles, and reduced HDL-C, which collectively increase CVD risk. Given the early genesis of atherosclerosis and physiological metabolic changes during adolescence, studying postprandial dyslipidemia in the adolescent population is an important area of study. Postprandial dyslipidemia in the pediatric population poses a significant public health concern, warranting a better understanding of its pathogenesis and association with insulin resistance and CVD. This review discusses the metabolic syndrome, focusing on the link between insulin resistance, postprandial dyslipidemia, and CVD risk. Furthermore, the clinical significance and functional assessment of postprandial dyslipidemia, specifically in the adolescent population, is discussed in more detail.
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Affiliation(s)
- Victoria Higgins
- Molecular Medicine and Pediatric Laboratory Medicine, Research Institute, The Hospital for Sick Children
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5G 1X8, Canada
| | - Khosrow Adeli
- Molecular Medicine and Pediatric Laboratory Medicine, Research Institute, The Hospital for Sick Children
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5G 1X8, Canada
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11
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Stahel P, Xiao C, Nahmias A, Lewis GF. Role of the Gut in Diabetic Dyslipidemia. Front Endocrinol (Lausanne) 2020; 11:116. [PMID: 32231641 PMCID: PMC7083132 DOI: 10.3389/fendo.2020.00116] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 02/21/2020] [Indexed: 12/13/2022] Open
Abstract
Type 2 diabetes (T2D) is associated with increased risk of cardiovascular disease (CVD). In insulin resistant states such as the metabolic syndrome, overproduction and impaired clearance of liver-derived very-low-density lipoproteins and gut-derived chylomicrons (CMs) contribute to hypertriglyceridemia and elevated atherogenic remnant lipoproteins. Although ingested fat is the major stimulus of CM secretion, intestinal lipid handling and ultimately CM secretory rate is determined by numerous additional regulatory inputs including nutrients, hormones and neural signals that fine tune CM secretion during fasted and fed states. Insulin resistance and T2D represent perturbed metabolic states in which intestinal sensitivity to key regulatory hormones such as insulin, leptin and glucagon-like peptide-1 (GLP-1) may be altered, contributing to increased CM secretion. In this review, we describe the evidence from human and animal models demonstrating increased CM secretion in insulin resistance and T2D and discuss the molecular mechanisms underlying these effects. Several novel compounds are in various stages of preclinical and clinical investigation to modulate intestinal CM synthesis and secretion. Their efficacy, safety and therapeutic utility are discussed. Similarly, the effects of currently approved lipid modulating therapies such as statins, ezetimibe, fibrates, and PCSK9 inhibitors on intestinal CM production are discussed. The intricacies of intestinal CM production are an active area of research that may yield novel therapies to prevent atherosclerotic CVD in insulin resistance and T2D.
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12
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Esfandiar Z, Hosseini-Esfahani F, Mirmiran P, Habibi-Moeini AS, Azizi F. Red meat and dietary iron intakes are associated with some components of metabolic syndrome: Tehran Lipid and Glucose Study. J Transl Med 2019; 17:313. [PMID: 31533731 PMCID: PMC6751740 DOI: 10.1186/s12967-019-2059-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 09/06/2019] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND This study was conducted to investigate whether the daily consumption of haem, non-haem, total iron and red meat can affect the occurrence of metabolic syndrome (MetS) and its components. METHODS Eligible adults (n = 4654) were selected from among participants of the Tehran Lipid and Glucose Study with an average follow-up of 3.8 years. Dietary intakes were assessed using a valid and reliable semi-quantitative food frequency questionnaire. Anthropometrics and biochemical variables were evaluated at baseline and follow-up examinations. The occurrence of MetS and its components were assessed in relation to haem, non-haem, total iron and red meat intakes. RESULTS There was no relationship between different types of dietary iron and red meat intakes and the incidence of MetS in the Tehranian population. Risk of hypertension decreased from quartiles 1 to 4 for haem iron (HR: 1.00, 0.92, 0.81, 0.80, Ptrend < 0.01) and red meat intake (HR: 1.00, 0.89, 0.84, 0.77, Ptrend < 0.01). The association between hyperglycemia and the fourth quartile of total iron intake was significant (HR = 1.98, 95% CI 1.08-3.63); and the risk of high triglyceride appeared to increase in higher quartiles of total iron intake (HR: 1.00, 1.17, 1.49, 1.75, Ptrend = 0.01) compared to lower quartiles. CONCLUSION Our study suggests a potentially protective relationship of haem and moderate red meat intake against development of high blood pressure; and higher intake of total iron is related to hyperglycemia and high triglyceride.
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Affiliation(s)
- Zohre Esfandiar
- Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Firoozeh Hosseini-Esfahani
- Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Parvin Mirmiran
- Nutrition and Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Ali-Siamak Habibi-Moeini
- Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fereidoun Azizi
- Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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13
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Whyte MB, Shojaee-Moradie F, Sharaf SE, Jackson NC, Fielding B, Hovorka R, Mendis J, Russell-Jones D, Umpleby AM. Lixisenatide Reduces Chylomicron Triacylglycerol by Increased Clearance. J Clin Endocrinol Metab 2019; 104:359-368. [PMID: 30215735 PMCID: PMC6300412 DOI: 10.1210/jc.2018-01176] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 09/06/2018] [Indexed: 12/17/2022]
Abstract
CONTEXT Glucagon-like peptide-1 (GLP-1) agonists control postprandial glucose and lipid excursion in type 2 diabetes; however, the mechanisms are unclear. OBJECTIVE To determine the mechanisms of postprandial lipid and glucose control with lixisenatide (GLP-1 analog) in type 2 diabetes. DESIGN Randomized, double-blind, cross-over study. SETTING Centre for Diabetes, Endocrinology, and Research, Royal Surrey County Hospital, Guildford, United Kingdom. PATIENTS Eight obese men with type 2 diabetes [age, 57.3 ± 1.9 years; body mass index, 30.3 ± 1.0 kg/m2; glycosylated hemoglobin, 66.5 ± 2.6 mmol/mol (8.2% ± 0.3%)]. INTERVENTIONS Two metabolic studies, 4 weeks after lixisenatide or placebo, with cross-over and repetition of studies. MAIN OUTCOME MEASURES Study one: very-low-density lipoprotein (VLDL) and chylomicron (CM) triacylglycerol (TAG) kinetics were measured with an IV bolus of [2H5]glycerol in a 12-hour study, with hourly feeding. Oral [13C]triolein, in a single meal, labeled enterally derived TAG. Study two: glucose kinetics were measured with [U-13C]glucose in a mixed-meal (plus acetaminophen to measure gastric emptying) and variable IV [6,6-2H2]glucose infusion. RESULTS Study one: CM-TAG (but not VLDL-TAG) pool-size was lower with lixisenatide (P = 0.046). Lixisenatide reduced CM [13C]oleate area under the curve (AUC)60-480min concentration (P = 0.048) and increased CM-TAG clearance, with no effect on CM-TAG production rate. Study two: postprandial glucose and insulin AUC0-240min were reduced with lixisenatide (P = 0.0051; P < 0.05). Total glucose production (P = 0.015), rate of glucose appearance from the meal (P = 0.0098), and acetaminophen AUC0-360min (P = 0.006) were lower with lixisenatide than with placebo. CONCLUSIONS Lixisenatide reduced [13C]oleate concentrations, derived from a single meal in CM-TAG and glucose rate of appearance from the meal through delayed gastric emptying. However, day-long CM production, measured with repeated meal feeding, was not reduced by lixisenatide and decreased CM-TAG concentration resulted from increased CM-TAG clearance.
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Affiliation(s)
- Martin B Whyte
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
- Correspondence and Reprint Requests: Martin B. Whyte, PhD, FRCP, Faculty of Health and Medical Sciences, University of Surrey, Leggett Building, Daphne Jackson Road, Guildford GU2 7WG, United Kingdom. E-mail:
| | | | - Sharaf E Sharaf
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Nicola C Jackson
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Barbara Fielding
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Roman Hovorka
- Diabetes Modelling Group, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - Jeewaka Mendis
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - David Russell-Jones
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - A Margot Umpleby
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
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14
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Drouin-Chartier JP, Tremblay AJ, Lemelin V, Lamarche B, Couture P. Differential associations between plasma concentrations of insulin and glucose and intestinal expression of key genes involved in chylomicron metabolism. Am J Physiol Gastrointest Liver Physiol 2018; 315:G177-G184. [PMID: 29698057 DOI: 10.1152/ajpgi.00108.2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The mechanisms underlying the oversecretion of apolipoprotein (apo)B-48-containing triglyceride-rich lipoproteins (TRL) in insulin-resistance (IR) states in humans remain to be fully understood. The objective of this study was to evaluate the association between the plasma levels of insulin and glucose and the intestinal expression of key genes involved in chylomicron metabolism in a large sample of nondiabetic men displaying various degrees of IR. Duodenal biopsies were obtained by gastroduodenoscopy in 127 men free of intestinal disease. Gene expression was measured using quantitative PCR in duodenal samples. Plasma insulin and glucose concentrations were measured in the fasting state. Postprandial TRL apoB-48 kinetics were measured using a primed-constant infusion of l-[5,5,5-D3]leucine for 12 h in a subgroup of 75 subjects maintained in a constant fed state. Plasma insulin levels were negatively associated with intestinal expression of ACS1 (standard β = -0.20, P = 0.007), DGAT1 (β = -0.18, P = 0.001), DGAT2 (β = -0.20, P = 0.02), and MTP (β = -0.27, P = 0.0005), whereas glucose levels were positively associated with MTP expression (β = 0.15, P = 0.04) independent of age, BMI, waist circumference, dietary intake, and duodenal expression of SREBP1c. Insulin levels, but not glucose concentrations, were positively correlated with postprandial TRL apoB-48 production rate ( r = 0.24, P = 0.04) and pool size ( r = 0.27, P = 0.03). In conclusion, plasma insulin and glucose levels are differentially associated with the expression of key genes involved in chylomicron metabolism. These results suggest that alterations in intestinal lipoprotein metabolism associated with IR may be regulated by plasma levels of both insulin and glucose concurrently and are therefore likely modified by the onset of insulin insufficiency. NEW & NOTEWORTHY We demonstrate that plasma insulin and glucose levels are differentially associated with the expression of key genes involved in chylomicron metabolism in men. For instance, intestinal expression of MTP is negatively associated with plasma insulin concentrations and positively associated with plasma glucose concentrations. Alterations in intestinal lipoprotein metabolism associated with insulin resistance may be regulated by plasma levels of both insulin and glucose concurrently and are therefore likely modified by the onset of insulin insufficiency.
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Affiliation(s)
| | - André J Tremblay
- Institute of Nutrition and Functional Foods, Laval University , Quebec City, Quebec , Canada
| | - Valéry Lemelin
- Department of Gastroenterology, Centre hospitalier universitaire de Québec-Laval University , Quebec City, Quebec , Canada
| | - Benoît Lamarche
- Institute of Nutrition and Functional Foods, Laval University , Quebec City, Quebec , Canada
| | - Patrick Couture
- Institute of Nutrition and Functional Foods, Laval University , Quebec City, Quebec , Canada.,Lipid Research Centre, Centre hospitalier universitaire de Québec-Laval University , Quebec City, Quebec , Canada
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15
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Abstract
Accumulating clinical evidence has suggested serum triglyceride (TG) is a leading predictor of atherosclerotic cardiovascular disease, comparable to low-density lipoprotein (LDL)-cholesterol (C) in populations with type 2 diabetes, which exceeds the predictive power of hemoglobinA1c. Atherogenic dyslipidemia in diabetes consists of elevated serum concentrations of TG-rich lipoproteins (TRLs), a high prevalence of small dense low-density lipoprotein (LDL), and low concentrations of cholesterol-rich high-density lipoprotein (HDL)2-C. A central lipoprotein abnormality is an increase in large TG-rich very-low-density lipoprotein (VLDL)1, and other lipoprotein abnormalities are metabolically linked to increased TRLs. Insulin critically regulates serum VLDL concentrations by suppressing hepatic VLDL production and stimulating VLDL removal by activation of lipoprotein lipase. It is still debated whether hyperinsulinemia compensatory for insulin resistance is causally associated with the overproduction of VLDL. This review introduces experimental and clinical observations revealing that insulin resistance, but not hyperinsulinemia stimulates hepatic VLDL production. LDL and HDL consist of heterogeneous particles with different size and density. Cholesterol-depleted small dense LDL and cholesterol-rich HDL2 subspecies are particularly affected by insulin resistance and can be named “Metabolic LDL and HDL,” respectively. We established the direct assays for quantifying small dense LDL-C and small dense HDL(HDL3)-C, respectively. Subtracting HDL3-C from HDL-C gives HDL2-C. I will explain clinical relevance of measurements of LDL and HDL subspecies determined by our assays. Diabetic kidney disease (DKD) substantially worsens plasma lipid profile thereby potentiated atherogenic risk. Finally, I briefly overview pathophysiology of dyslipidemia associated with DKD, which has not been so much taken up by other review articles.
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Affiliation(s)
- Tsutomu Hirano
- Department of Medicine, Division of Diabetes, Metabolism, and Endocrinology, Showa University School of Medicine
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16
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Dos Santos Vieira DA, Hermes Sales C, Galvão Cesar CL, Marchioni DM, Fisberg RM. Influence of Haem, Non-Haem, and Total Iron Intake on Metabolic Syndrome and Its Components: A Population-Based Study. Nutrients 2018. [PMID: 29518910 PMCID: PMC5872732 DOI: 10.3390/nu10030314] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Studies suggest that haem, non-haem iron and total iron intake may be related to non-communicable diseases, especially metabolic syndrome. This study was undertaken to investigate the association of haem, non-haem iron and total iron intake with metabolic syndrome and its components. A cross-sectional population-based survey was performed in 2008, enrolling 591 adults and elderly adults living in São Paulo, Brazil. Dietary intake was measured by two 24 h dietary recalls. Metabolic syndrome was defined as the presence of at least three of the following: hypertension, hyperglycaemia, dyslipidaemia and central obesity. The association between different types of dietary iron and metabolic syndrome was evaluated using multiple logistic regression. After adjustment for potential confounders, a higher haem iron intake was positively associated with metabolic syndrome and with elevated triglyceride levels. A higher total iron intake was positively associated with hyperglycaemia. Non-haem iron intake was positively associated with hyperglycaemia in the fourth quintile. In conclusion, this study suggests that the different types of dietary iron are associated with metabolic syndrome, elevated triglyceride levels and hyperglycaemia. In addition, it emphasises the importance of investigating the roles of dietary iron in health outcomes, since its consumption may have different impacts on health.
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Affiliation(s)
- Diva Aliete Dos Santos Vieira
- Department of Nutrition, School of Public Health, University of Sao Paulo, Av. Dr. Arnaldo, 715, Cerqueira César, São Paulo, SP 01246-904, Brazil.
| | - Cristiane Hermes Sales
- Department of Nutrition, School of Public Health, University of Sao Paulo, Av. Dr. Arnaldo, 715, Cerqueira César, São Paulo, SP 01246-904, Brazil.
| | - Chester Luiz Galvão Cesar
- Department of Epidemiology, School of Public Health, University of Sao Paulo, Av. Dr. Arnaldo, 715, Cerqueira César, São Paulo, SP 01246-904, Brazil.
| | - Dirce Maria Marchioni
- Department of Nutrition, School of Public Health, University of Sao Paulo, Av. Dr. Arnaldo, 715, Cerqueira César, São Paulo, SP 01246-904, Brazil.
| | - Regina Mara Fisberg
- Department of Nutrition, School of Public Health, University of Sao Paulo, Av. Dr. Arnaldo, 715, Cerqueira César, São Paulo, SP 01246-904, Brazil.
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17
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Xiao C, Stahel P, Carreiro AL, Buhman KK, Lewis GF. Recent Advances in Triacylglycerol Mobilization by the Gut. Trends Endocrinol Metab 2018; 29:151-163. [PMID: 29306629 DOI: 10.1016/j.tem.2017.12.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 11/30/2017] [Accepted: 12/04/2017] [Indexed: 11/26/2022]
Abstract
Dietary lipid absorption and lipoprotein secretion by the gut are important in maintaining whole-body energy homeostasis and have significant implications for health and disease. The processing of dietary lipids, including storage within and subsequent mobilization and transport from enterocyte cytoplasmic lipid droplets or other intestinal lipid storage pools (including the secretary pathway, lamina propria and lymphatics) and secretion of chylomicrons, involves coordinated steps that are subject to various controls. This review summarizes recent advances in our understanding of the mechanisms that underlie lipid storage and mobilization by small intestinal enterocytes and the intestinal lymphatic vasculature. Therapeutic targeting of lipid processing by the gut may provide opportunities for the treatment and prevention of dyslipidemia, and for improving health status.
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Affiliation(s)
- Changting Xiao
- Departments of Medicine and Physiology, Division of Endocrinology and Metabolism, Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada
| | - Priska Stahel
- Departments of Medicine and Physiology, Division of Endocrinology and Metabolism, Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada
| | - Alicia L Carreiro
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA
| | - Kimberly K Buhman
- Department of Nutrition Science, Purdue University, West Lafayette, IN 47907, USA
| | - Gary F Lewis
- Departments of Medicine and Physiology, Division of Endocrinology and Metabolism, Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada.
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18
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Drouin-Chartier JP, Tremblay AJ, Lépine MC, Lemelin V, Lamarche B, Couture P. Substitution of dietary ω-6 polyunsaturated fatty acids for saturated fatty acids decreases LDL apolipoprotein B-100 production rate in men with dyslipidemia associated with insulin resistance: a randomized controlled trial. Am J Clin Nutr 2018; 107:26-34. [PMID: 29381796 PMCID: PMC5972657 DOI: 10.1093/ajcn/nqx013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Accepted: 10/24/2017] [Indexed: 12/11/2022] Open
Abstract
Background The substitution of omega (ω)-6 (n-6) polyunsaturated fatty acids (PUFAs) for saturated fatty acids (SFAs) is advocated in cardiovascular disease prevention. The impact of this substitution on lipoprotein metabolism in subjects with dyslipidemia associated with insulin resistance (IR) remains unknown. Objective In men with dyslipidemia and IR, we evaluated the impact of substituting ω-6 PUFAs for SFAs on the in vivo kinetics of apolipoprotein (apo) B-containing lipoproteins and on the intestinal expression of key genes involved in lipoprotein metabolism. Design Dyslipidemic and IR men (n = 36) were recruited for this double-blind, randomized, crossover, controlled trial. Subjects consumed, in a random order, a fully controlled diet rich in SFAs (SFAs: 13.4% of energy; ω-6 PUFAs: 4.0%) and a fully controlled diet rich in ω-6 PUFAs (SFAs: 6.0%; ω-6 PUFAs: 11.3%) for periods of 4 wk, separated by a 4-wk washout period. At the end of each diet, the in vivo kinetics of apoB-containing lipoproteins were measured and the intestinal expression of key genes involved in lipoprotein metabolism was quantified in duodenal biopsies taken from each participant. Results The substitution of ω-6 PUFAs for SFAs had no impact on TRL apoB-48 fractional catabolic rate (Δ = -3.8%, P = 0.7) and production rate (Δ = +1.2%, P = 0.9), although it downregulated the intestinal expression of the microsomal triglyceride transfer protein (Δ = -18.4%, P = 0.006) and apoB (Δ = -16.6%, P = 0.005). The substitution of ω-6 PUFAs for SFAs decreased the LDL apoB-100 pool size (Δ = -7.8%; P = 0.005). This difference was attributed to a reduction in the LDL apoB-100 production rate after the substitution of ω-6 PUFAs for SFAs (Δ = -10.0%; P = 0.003). Conclusions This study demonstrates that the substitution of dietary ω-6 PUFAs for SFAs decreases the production and number of LDL particles in men with dyslipidemia and IR. This trial was registered at clinicaltrials.gov as NCT01934543.
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Affiliation(s)
| | - André J Tremblay
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Quebec, Canada
| | - Marie-Claude Lépine
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Quebec, Canada
| | - Valéry Lemelin
- Department of Gastroenterology and Lipid Research Center, CHU de Québec-Université Laval, Quebec City, Quebec, Canada
| | - Benoît Lamarche
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Quebec, Canada
| | - Patrick Couture
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Quebec, Canada,Lipid Research Center, CHU de Québec-Université Laval, Quebec City, Quebec, Canada,Address correspondence to PC (e-mail: )
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19
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Xiao C, Dash S, Stahel P, Lewis GF. Effects of Intranasal Insulin on Triglyceride-Rich Lipoprotein Particle Production in Healthy Men. Arterioscler Thromb Vasc Biol 2017; 37:1776-1781. [DOI: 10.1161/atvbaha.117.309705] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 07/17/2017] [Indexed: 02/07/2023]
Affiliation(s)
- Changting Xiao
- From the Division of Endocrinology and Metabolism, Department of Medicine and Department of Physiology, Banting and Best Diabetes Centre, University of Toronto, Ontario, Canada
| | - Satya Dash
- From the Division of Endocrinology and Metabolism, Department of Medicine and Department of Physiology, Banting and Best Diabetes Centre, University of Toronto, Ontario, Canada
| | - Priska Stahel
- From the Division of Endocrinology and Metabolism, Department of Medicine and Department of Physiology, Banting and Best Diabetes Centre, University of Toronto, Ontario, Canada
| | - Gary F. Lewis
- From the Division of Endocrinology and Metabolism, Department of Medicine and Department of Physiology, Banting and Best Diabetes Centre, University of Toronto, Ontario, Canada
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20
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Rydén M, Arner P. Subcutaneous Adipocyte Lipolysis Contributes to Circulating Lipid Levels. Arterioscler Thromb Vasc Biol 2017; 37:1782-1787. [PMID: 28663255 PMCID: PMC5567402 DOI: 10.1161/atvbaha.117.309759] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 06/21/2017] [Indexed: 11/16/2022]
Abstract
Supplemental Digital Content is available in the text. Objective— Fatty acids released via fat cell lipolysis can affect circulating lipid levels. However, the contribution of different lipolysis measures in adipose tissue is unknown and was presently examined in isolated subcutaneous adipocytes. Approach and Results— One thousand and sixty-six men and women were examined for lipolysis regulation in subcutaneous abdominal fat cells. Results were compared with fasting plasma levels of total cholesterol, high-density lipoprotein (HDL) cholesterol (HDL-C) and triglycerides. Spontaneous (basal) lipolysis and the effects of the major hormones stimulating (catecholamines and natriuretic peptides) and inhibiting lipolysis (insulin) were examined. Several statistically significant (P<0.0001) correlations between the different lipolysis parameters and plasma lipids were observed. However, physiologically relevant correlations (adjusted r2≥0.05) were only evident between basal or insulin-inhibited lipolysis and plasma triglycerides or HDL-C. Together, these lipolysis measures explained 14% of the variation in triglycerides or HDL-C, respectively. In comparison, a combination of established factors associated with variations in plasma lipids, that is, age; body mass index; waist circumference; waist-to-hip ratio; sex; nicotine use; fat cell volume; and pharmacotherapy against diabetes mellitus; hypertension; or hyperlipidemia explained 17% and 28%, respectively, of the variations in plasma triglycerides and HDL-C. Conclusions— Subcutaneous fat cell lipolysis is an important independent contributor to interindividual variations in plasma lipids. High spontaneous lipolysis activity and resistance to the antilipolytic effect of insulin associate with elevated triglyceride and low HDL-C concentrations. Thus, although several other factors also play a role, subcutaneous adipose tissue may have a causal influence on dyslipidemia.
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Affiliation(s)
- Mikael Rydén
- From the Department of Medicine, Karolinska Institutet at Karolinska University Hospital, Huddinge, Stockholm, Sweden.
| | - Peter Arner
- From the Department of Medicine, Karolinska Institutet at Karolinska University Hospital, Huddinge, Stockholm, Sweden.
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21
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Influence on Adiposity and Atherogenic Lipaemia of Fatty Meals and Snacks in Daily Life. J Lipids 2017; 2017:1375342. [PMID: 28706738 PMCID: PMC5494570 DOI: 10.1155/2017/1375342] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/02/2017] [Accepted: 05/09/2017] [Indexed: 11/18/2022] Open
Abstract
The present work reviewed the connections of changes in consumption of high-fat food with changes in adiposity and lipaemia in adults with overweight or obesity. Hyperlipaemia from higher fat meals and excessive adiposity contributes to atherogenic process. Low-fat diet interventions decrease body fat, lipaemia, and atherosclerosis markers. Inaccuracy of physical estimates of dietary fat intake remains, however, a limit to establishing causal connections. To fill this gap, tracking fat-rich eating episodes at short intervals quantifies the behavioural frequency suggested to measure (by regression of changes in real time) direct effects of this eating pattern on adiposity and atherogenic lipaemia. Such evidence will provide the basis for an approach focused on a sustained decrease in frequency of fatty meals or snacks to reduce obesity, hyperlipaemia, and atherosclerosis.
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22
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Drouin-Chartier JP, Tremblay AJ, Hogue JC, Leclerc M, Labonté MÈ, Marin J, Lamarche B, Couture P. C-reactive protein levels are inversely correlated with the apolipoprotein B-48-containing triglyceride-rich lipoprotein production rate in insulin resistant men. Metabolism 2017; 68:163-172. [PMID: 28183448 DOI: 10.1016/j.metabol.2016.11.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Revised: 11/18/2016] [Accepted: 11/30/2016] [Indexed: 01/16/2023]
Abstract
UNLABELLED The pro-inflammatory state and elevated plasma levels of post-prandial triglycerides (TG) are associated with increased cardiovascular disease risk. Recent studies suggested that the increase in the production rate of post-prandial lipoproteins observed in patients with insulin resistance (IR) may be caused, at least in part, by the dysregulation of intestinal insulin sensitivity triggered by inflammation. OBJECTIVE The objective of the present study was to evaluate the association between IR, plasma C-reactive protein (CRP) levels and the kinetics of TG-rich lipoprotein (TRL) containing apolipoprotein (apo) B-48 in a large sample of insulin sensitive (IS) and IR men. METHODS The in vivo kinetics of TRL apoB-48 were measured in 151 men following a primed-constant infusion of l-[5,5,5-D3]leucine. IR subjects (n=91) were characterized by fasting TG levels ≥1.5mmol/L and an index of homeostasis model assessment of IR (HOMA-IR)≥2.5 or type 2 diabetes, while IS subjects (n=24) were characterized by an HOMA-IR index <2.5 and TG levels <1.5mmol/L. RESULTS IR subjects had higher TRL apoB-48 production rate (+202%; P<0.0001) and CRP levels (+51%; P=0.01) than IS subjects. TRL apoB-48 production rate and CRP levels were inversely correlated in IR subjects (r=-0.32; P=0.002). IR subjects with CRP levels above the median (2.20mg/L) had lower TRL apoB-48 production rate than IR subjects with CRP levels below the median (Δ=-24%; P<0.05). CONCLUSION Our results confirm that IR is associated with increased TRL apoB-48 secretion and suggest that a higher inflammatory status is associated with decreased TRL apoB-48 secretion among IR subjects.
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Affiliation(s)
| | - André J Tremblay
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada
| | | | - Myriam Leclerc
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada
| | - Marie-Ève Labonté
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada
| | - Johanne Marin
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada
| | - Benoît Lamarche
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada
| | - Patrick Couture
- Institute of Nutrition and Functional Foods, Laval University, Quebec City, Canada; CHUQ Research Center, Laval University, Quebec City, Canada.
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Abstract
PURPOSE OF REVIEW Experimental evidences are strong for a role of long-chain saturated fatty acids in the development of insulin resistance and type 2 diabetes. Ectopic accretion of triglycerides in lean organs is a characteristic of prediabetes and type 2 diabetes and has been linked to end-organ complications. The contribution of disordered dietary fatty acid (DFA) metabolism to lean organ overexposure and lipotoxicity is still unclear, however. DFA metabolism is very complex and very difficult to study in vivo in humans. RECENT FINDINGS We have recently developed a novel imaging method using PET with oral administration of 14-R,S-F-fluoro-6-thia-heptadecanoic acid (FTHA) to quantify organ-specific DFA partitioning. Our studies thus far confirmed impaired storage of DFA per volume of fat mass in abdominal adipose tissues of individuals with prediabetes. They also highlighted the increased channeling of DFA toward the heart, associated with subclinical reduction in cardiac systolic and diastolic function in individuals with prediabetes. SUMMARY In the present review, we summarize previous work on DFA metabolism in healthy and prediabetic states and discuss these in the light of our novel findings using PET imaging of DFA metabolism. We herein provide an integrated view of abnormal organ-specific DFA partitioning in prediabetes in humans.
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Affiliation(s)
- Christophe Noll
- Division of Endocrinology, Department of Medicine, Centre de recherche du CHUS, Université de Sherbrooke, Sherbrooke, Quebec, Canada
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Ginsberg H, Cariou B, Orchard T, Chen L, Luo J, Bastyr EJ, Bue-Valleskey J, Chang AM, Ivanyi T, Jacober SJ, Hoogwerf BJ. Lipid changes during basal insulin peglispro, insulin glargine, or NPH treatment in six IMAGINE trials. Diabetes Obes Metab 2016; 18:1089-1092. [PMID: 27486125 DOI: 10.1111/dom.12754] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 07/25/2016] [Accepted: 07/27/2016] [Indexed: 01/05/2023]
Abstract
Basal insulin peglispro (BIL) is a novel basal insulin with hepato-preferential action resulting from reduced peripheral effects. This report provides an integrated summary of lipid changes at 26 weeks with BIL and comparator insulins (glargine, NPH) from phase III studies in type 1 diabetes (T1D), insulin-naïve patients with type 2 diabetes (T2D), patients with T2D on basal insulin only and patients with T2D on basal-bolus therapy. BIL treatment had little effect on HDL cholesterol and LDL cholesterol in all patients. The effect of both BIL and glargine treatment on triglycerides (TG) depended on whether patients had been previously treated with insulin. When BIL replaced conventional insulin glargine or NPH treatments, increases in TG levels were observed. When BIL or comparator insulins were given for 26 weeks to insulin-naïve patients with T2D, TG levels were unchanged from baseline with BIL but decreased with either glargine or NPH. The decreased peripheral action of BIL may reduce suppression of lipolysis in peripheral adipose tissue resulting in increased free fatty acid delivery to the liver and, hence, increased hepatic TG synthesis and secretion.
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Affiliation(s)
- Henry Ginsberg
- Irving Institute for Clinical and Translational Research, Columbia University, New York, New York, USA
| | - Bertrand Cariou
- Department of Endocrinology, L'Institut du Thorax, CHU Nantes, Nantes, France
| | - Trevor Orchard
- Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Lei Chen
- Eli Lilly and Company, Indianapolis, Indiana, USA
| | - Junxiang Luo
- Eli Lilly and Company, Indianapolis, Indiana, USA
| | - Edward J Bastyr
- Eli Lilly and Company, Indianapolis, Indiana, USA
- Division of Endocrinology & Metabolism, Indiana University School of Medicine, Indianapolis, Indiana, USA
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Diane A, Pierce WD, Kelly SE, Sokolik S, Borthwick F, Jacome-Sosa M, Mangat R, Pradillo JM, Allan SM, Ruth MR, Field CJ, Hutcheson R, Rocic P, Russell JC, Vine DF, Proctor SD. Mechanisms of Comorbidities Associated With the Metabolic Syndrome: Insights from the JCR:LA-cp Corpulent Rat Strain. Front Nutr 2016; 3:44. [PMID: 27777929 PMCID: PMC5056323 DOI: 10.3389/fnut.2016.00044] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 09/23/2016] [Indexed: 01/08/2023] Open
Abstract
Obesity and its metabolic complications have emerged as the epidemic of the new millennia. The use of obese rodent models continues to be a productive component of efforts to understand the concomitant metabolic complications of this disease. In 1978, the JCR:LA-cp rat model was developed with an autosomal recessive corpulent (cp) trait resulting from a premature stop codon in the extracellular domain of the leptin receptor. Rats that are heterozygous for the cp trait are lean-prone, while those that are homozygous (cp/cp) spontaneously display the pathophysiology of obesity as well as a metabolic syndrome (MetS)-like phenotype. Over the years, there have been formidable scientific contributions that have originated from this rat model, much of which has been reviewed extensively up to 2008. The premise of these earlier studies focused on characterizing the pathophysiology of MetS-like phenotype that was spontaneously apparent in this model. The purpose of this review is to highlight areas of recent advancement made possible by this model including; emerging appreciation of the "thrifty gene" hypothesis in the context of obesity, the concept of how chronic inflammation may drive obesogenesis, the impact of acute forms of inflammation to the brain and periphery during chronic obesity, the role of dysfunctional insulin metabolism on lipid metabolism and vascular damage, and the mechanistic basis for altered vascular function as well as novel parallels between the human condition and the female JCR:LA-cp rat as a model for polycystic ovary disease (PCOS).
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Affiliation(s)
- Abdoulaye Diane
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
| | - W. David Pierce
- Department of Sociology, University of Alberta, Edmonton, AB, Canada
| | - Sandra E. Kelly
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
| | - Sharon Sokolik
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
| | - Faye Borthwick
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
| | - Miriam Jacome-Sosa
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
| | - Rabban Mangat
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
| | | | - Stuart McRae Allan
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Megan R. Ruth
- Department of Agricultural Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | - Catherine J. Field
- Department of Agricultural Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | | | | | - James C. Russell
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
| | - Donna F. Vine
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
| | - Spencer D. Proctor
- Metabolic and Cardiovascular Diseases Laboratory, Division of Human Nutrition, Alberta Diabetes and Mazakowski Heart Institutes, University of Alberta, Edmonton, AB, Canada
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Xiao C, Dash S, Morgantini C, Lewis GF. Intravenous Glucose Acutely Stimulates Intestinal Lipoprotein Secretion in Healthy Humans. Arterioscler Thromb Vasc Biol 2016; 36:1457-63. [PMID: 27150393 DOI: 10.1161/atvbaha.115.307044] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 04/20/2016] [Indexed: 12/28/2022]
Abstract
OBJECTIVE Increased production of intestinal triglyceride-rich lipoproteins (TRLs) contributes to dyslipidemia and increased risk of atherosclerotic cardiovascular disease in insulin resistance and type 2 diabetes. We have previously demonstrated that enteral glucose enhances lipid-stimulated intestinal lipoprotein particle secretion. Here, we assessed whether glucose delivered systemically by intravenous infusion also enhances intestinal lipoprotein particle secretion in humans. APPROACH AND RESULTS On 2 occasions, 4 to 6 weeks apart and in random order, 10 healthy men received a constant 15-hour intravenous infusion of either 20% glucose to induce hyperglycemia or normal saline as control. Production of TRL-apolipoprotein B48 (apoB48, primary outcomes) and apoB100 (secondary outcomes) was assessed during hourly liquid-mixed macronutrient formula ingestion with stable isotope enrichment and multicompartmental modeling, under pancreatic clamp conditions to limit perturbations in pancreatic hormones (insulin and glucagon) and growth hormone. Compared with saline infusion, glucose infusion induced both hyperglycemia and hyperinsulinemia, increased plasma triglyceride levels, and increased TRL-apoB48 concentration and production rate (P<0.05), without affecting TRL-apoB48 fractional catabolic rate. No significant effect of hyperglycemia on TRL-apoB100 concentration and kinetic parameters was observed. CONCLUSIONS Short-term intravenous infusion of glucose stimulates intestinal lipoprotein production. Hyperglycemia may contribute to intestinal lipoprotein overproduction in type 2 diabetes. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT02607839.
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Affiliation(s)
- Changting Xiao
- From the Division of Endocrinology and Metabolism, Department of Medicine and Physiology, Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada
| | - Satya Dash
- From the Division of Endocrinology and Metabolism, Department of Medicine and Physiology, Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada
| | - Cecilia Morgantini
- From the Division of Endocrinology and Metabolism, Department of Medicine and Physiology, Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada
| | - Gary F Lewis
- From the Division of Endocrinology and Metabolism, Department of Medicine and Physiology, Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada.
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Update on the molecular biology of dyslipidemias. Clin Chim Acta 2016; 454:143-85. [DOI: 10.1016/j.cca.2015.10.033] [Citation(s) in RCA: 82] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/24/2015] [Accepted: 10/30/2015] [Indexed: 12/20/2022]
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The expression of genes involved in jejunal lipogenesis and lipoprotein synthesis is altered in morbidly obese subjects with insulin resistance. J Transl Med 2015; 95:1409-17. [PMID: 26367490 DOI: 10.1038/labinvest.2015.115] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 07/03/2015] [Accepted: 07/28/2015] [Indexed: 12/28/2022] Open
Abstract
The dyslipidemia associated with type 2 diabetes mellitus (T2DM) is an important risk factor for atherosclerotic cardiovascular disease. However, until now little attention has been paid to the role that the intestine might have. The aim of this research was to determine the relation between insulin resistance and intestinal de novo lipogenesis/lipoprotein synthesis in morbidly obese subjects and to study the effect of insulin on these processes. Jejunal mRNA expression of the different genes involved in the intestinal de novo lipogenesis/lipoprotein synthesis was analyzed in three groups of morbidly obese subjects: Group 1 with low insulin resistance (MO-low-IR), group 2 with high insulin resistance (MO-high-IR), and group 3 with T2DM and treatment with metformin (MO-metf-T2DM). In addition, intestinal epithelial cells (IECs) from MO-low-IR were incubated with different doses of insulin/glucose. In Group 2 (MO-high-IR), the jejunal mRNA expression levels of apo A-IV, ATP-citrate lyase (ACLY), pyruvate dehydrogenase (lipoamide) beta (PDHB), and sterol regulatory element-binding protein-1c (SREBP-1c) were significantly higher and acetyl-CoA carboxylase alpha (ACC1) and fatty-acid synthase lower than in Group 1 (MO-low-IR). In Group 3 (MO-metf-T2DM), only the ACLY and PDHB mRNA expressions were significantly higher than in Group 1 (MO-low-IR). The mRNA expression of most of the genes studied was significantly linked to insulin and glucose levels. The incubation of IEC with different doses of insulin and glucose produced a higher expression of diacylglycerol acyltransferase 2, microsomal triglyceride transfer protein, apo A-IV, SREBP-1c, and ACC1 when both, glucose and insulin, were at a high concentration. However, with only high insulin levels, there were higher apo A-IV, PDHB and SREBP-1c expressions, and a lower ACLY expression. In conclusion, the jejunum of MO-high-IR has a decreased mRNA expression of genes involved in de novo fatty-acid synthesis and an increase of genes involved in acetyl-CoA and lipoprotein synthesis. This effect is attenuated by metformin. In addition, the expression of most of the genes studied was found to be regulated by insulin.
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Shah KN, Patel SS. Phosphatidylinositide 3-kinase inhibition: A new potential target for the treatment of polycystic ovarian syndrome. PHARMACEUTICAL BIOLOGY 2015; 54:975-83. [PMID: 26459667 PMCID: PMC11133948 DOI: 10.3109/13880209.2015.1091482] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 08/27/2015] [Accepted: 09/02/2015] [Indexed: 06/05/2023]
Abstract
CONTEXT Quercetin, a flavonoid, has been tried in traditional medicine for treating many disorders and reported to have inhibitory action on PI3 kinase. OBJECTIVE This study investigates the effect of quercetin on testosterone propionate induced polycystic ovary syndrome (PCOS) model, which shows both metabolic and endocrine features of PCOS. MATERIALS AND METHODS Female pre-pubertal Sprague-Dawley rats were randomly divided into four groups: normal control, PCOS control, quercetin, and metformin treated. PCOS was induced by testosterone propionate (10 mg/kg, s.c.) and treatments were carried out orally at the dose of 150 mg/kg from the 6th week. At the 6th and 10th week, blood was collected to investigate metabolic indices, and reproductive biochemical parameters including morphology of ovary, uterus, and estrous cyclicity were assessed. The ovaries were processed to determine CYP17A1 gene expression. RESULTS The treatment with quercetin did not modify body weight gain but uterine (296.7 ± 5.11 versus 263.0 ± 8.60 mg) and ovary weights (49.5 ± 1.93 versus 37.8 ± 3.43 mg) were found to be decreased significantly (p <0.05) as compared with the PCOS control group. The PCOS control group showed hyperinsulinemia, hyperandrogenemia, and dyslipidemia. Treatment with quercetin showed statistically significant (p <0.01) improvement in insulin (12.46 ± 0.3 versus 10.0 ± 0.28 μU/ml), testosterone (0.65 ± 0.02 versus 0.29 ± 0.02 μU/ml), luteinising hormone (20.6 ± 0.28 versus 15.1 ± 0.36 U/ml), and lipid profile. Histological examination of ovary and uterus confirmed the disease occurrence and remission state in the diseased and treated groups, respectively. Quercetin also demonstrated PI3 kinase inhibition in a docking study and decreased CYP17A1 gene expression. DISCUSSION AND CONCLUSION Thus, we can conclude that quercetin may have beneficial effect in PCOS by virtue of inhibition of PI3K which attributes to a decrease in the expression of CYP17A1 gene, having a key role in steroidogenesis.
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Affiliation(s)
| | - Snehal S. Patel
- Institute of Pharmacy, Nirma University, Ahmedabad, Gujarat, India
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Hashimoto S, Mizutani E, Suzuki M, Yoshida A, Naito M. Effects of Aerobic Exercise on Postprandial Carbohydrate and Lipoprotein Metabolism Following Cookie Ingestion in Healthy Young Women. J Nutr Sci Vitaminol (Tokyo) 2015; 61:299-305. [PMID: 26440636 DOI: 10.3177/jnsv.61.299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We examined the acute effects of postprandial aerobic exercise on glucose and lipid metabolism following cookie ingestion. Fifteen healthy young women with a sedentary lifestyle, normal weight and apolipoprotein E3/3 participated. After a 12-h overnight fast, each subject ingested a cookie (1.53 g/kg, Meal Test C) and then performed two trials, one with postprandial exercise (E trial) and one without exercise (C trial), in a randomized crossover design. A single 30-min bout of walking exercise was performed 20 min after the cookie intake. Venous blood samples were drawn before (0 h) and 20 min and 1, 2, 4, and 6 h after cookie ingestion. The Δglucose concentration was not significantly different between the two trials, but the Δinsulin concentration at 1 h and the incremental area under the curve (IAUC) (0-2 h)-insulin in the E trial were significantly lower than in the C trial. The ratio of glucose/insulin at 1 h was significantly higher in the E trial than in the C trial. The ΔTG, ΔRLP-TG, ΔapoB48 and ΔRemL-C concentrations at 1 h in the E trial were significantly higher than in the C trial. The IAUC (0-2 h)-apoB48 in the E trial was significantly larger than in the C trial. Postprandial exercise showed an insulin-sparing effect following the cookie ingestion by increasing insulin sensitivity. However, postprandial exercise transiently stimulated the secretion of exogenous apoB48-containing lipoprotein during the early period, and no further effects were observed. These results suggest that postprandial aerobic exercise is effective for the promotion of postprandial carbohydrate metabolism, but not lipidemia.
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Affiliation(s)
- Sayuki Hashimoto
- Division of Nutrition & Health, School & Graduate School of Life Studies, Sugiyama Jogakuen University
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Hsieh J, Trajcevski KE, Farr SL, Baker CL, Lake EJ, Taher J, Iqbal J, Hussain MM, Adeli K. Glucagon-Like Peptide 2 (GLP-2) Stimulates Postprandial Chylomicron Production and Postabsorptive Release of Intestinal Triglyceride Storage Pools via Induction of Nitric Oxide Signaling in Male Hamsters and Mice. Endocrinology 2015; 156:3538-47. [PMID: 26132919 DOI: 10.1210/en.2015-1110] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The intestinal overproduction of apolipoprotein B48 (apoB48)-containing chylomicron particles is a common feature of diabetic dyslipidemia and contributes to cardiovascular risk in insulin resistant states. We previously reported that glucagon-like peptide-2 (GLP-2) is a key endocrine stimulator of enterocyte fat absorption and chylomicron output in the postprandial state. GLP-2's stimulatory effect on chylomicron production in the postabsorptive state has been confirmed in human studies. The mechanism by which GLP-2 regulates chylomicron production is unclear, because its receptor is not expressed on enterocytes. We provide evidence for a key role of nitric oxide (NO) in mediating the stimulatory effects of GLP-2 during the postprandial and postabsorptive periods. Intestinal chylomicron production was assessed in GLP-2-treated hamsters administered the pan-specific NO synthase (NOS) inhibitor L-N(G)-nitroarginine methyl ester (L-NAME), and in GLP-2-treated endothelial NOS knockout mice. L-NAME blocked GLP-2-stimulated apoB48 secretion and reduced triglycerides (TGs) in the TG-rich lipoprotein (TRL) fraction of the plasma in the postprandial state. Endothelial NOS-deficient mice were resistant to GLP-2 stimulation and secreted fewer large apoB48-particles. When TG storage pools were allowed to accumulate, L-NAME mitigated the GLP-2-mediated increase in TRL-TG, suggesting that NO is required for early mobilization and secretion of stored TG and preformed chylomicrons. Importantly, the NO donor S-nitroso-L-glutathione was able to elicit an increase in TRL-TG in vivo and stimulate chylomicron release in vitro in primary enterocytes. We describe a novel role for GLP-2-mediated NO-signaling as a critical regulator of intestinal lipid handling and a potential contributor to postprandial dyslipidemia.
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Affiliation(s)
- Joanne Hsieh
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
| | - Karin E Trajcevski
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
| | - Sarah L Farr
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
| | - Christopher L Baker
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
| | - Elizabeth J Lake
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
| | - Jennifer Taher
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
| | - Jahangir Iqbal
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
| | - Mahmood M Hussain
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
| | - Khosrow Adeli
- Molecular Structure and Function (J.H., K.E.T., S.L.F., C.L.B., E.J.L., J.T., K.A.), Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada, M5G 1X8; Departments of Biochemistry (J.H., K.E.T., K.A.) and Laboratory Medicine and Pathobiology (S.L.F., J.T., K.A.), University of Toronto, Toronto, Ontario, Canada, M5S 1A8; and State University of New York Downstate Medical Center (J.I., M.H.H.), Brooklyn, New York 11203
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Veilleux A, Mayeur S, Bérubé JC, Beaulieu JF, Tremblay E, Hould FS, Bossé Y, Richard D, Levy E. Altered intestinal functions and increased local inflammation in insulin-resistant obese subjects: a gene-expression profile analysis. BMC Gastroenterol 2015; 15:119. [PMID: 26376914 PMCID: PMC4574092 DOI: 10.1186/s12876-015-0342-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 08/25/2015] [Indexed: 03/15/2023] Open
Abstract
BACKGROUND Metabolic alterations relevant to postprandial dyslipidemia were previously identified in the intestine of obese insulin-resistant subjects. The aim of the study was to identify the genes deregulated by systemic insulin resistance in the intestine of severely obese subjects. METHODS Transcripts from duodenal samples of insulin-sensitive (HOMA-IR < 3, n = 9) and insulin-resistant (HOMA-IR > 7, n = 9) obese subjects were assayed by microarray (Illumina HumanHT-12). RESULTS A total of 195 annotated genes were identified as differentially expressed between these two groups (Fold change > 1.2). Of these genes, 36 were found to be directly involved in known intestinal functions, including digestion, extracellular matrix, endocrine system, immunity and cholesterol metabolism. Interestingly, all differentially expressed genes (n = 8) implicated in inflammation and oxidative stress were found to be upregulated in the intestine of insulin-resistant compared to insulin-sensitive subjects. Metabolic pathway analysis revealed that several signaling pathways involved in immunity and inflammation were significantly enriched in differently expressed genes and were predicted to be activated in the intestine of insulin-resistant subjects. Using stringent criteria (Fold change > 1.5; FDR < 0.05), three genes were found to be significantly and differently expressed in the intestine of insulin-resistant compared to insulin-sensitive subjects: the transcripts of the insulinotropic glucose-dependant peptide (GIP) and of the β-microseminoprotein (MSMB) were significantly reduced, but that of the humanin like-1 (MTRNR2L1) was significantly increased. CONCLUSION These results underline that systemic insulin resistance is associated with remodeling of key intestinal functions. Moreover, these data indicate that small intestine metabolic dysfunction is accompanied with a local amplification of low-grade inflammatory process implicating several pathways. Genes identified in this study are potentially triggered throughout the development of intestinal metabolic abnormalities, which could contribute to dyslipidemia, a component of metabolic syndrome and diabetes.
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Affiliation(s)
- Alain Veilleux
- Department of Nutrition, Université de Montréal and Research center of CHU Sainte-Justine, 3175 Côte Ste-Catherine, Montréal, Qc, Canada.
| | - Sylvain Mayeur
- Department of Nutrition, Université de Montréal and Research center of CHU Sainte-Justine, 3175 Côte Ste-Catherine, Montréal, Qc, Canada.
| | - Jean-Christophe Bérubé
- Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Qc, Canada.
| | - Jean-François Beaulieu
- Departement of Anatomy and cellular biology, Université de Sherbrooke, Sherbrooke, Qc, Canada. .,Canada Research Chair in Intestinal Physiopathology, Sherbrooke, Québec, Canada.
| | - Eric Tremblay
- Departement of Anatomy and cellular biology, Université de Sherbrooke, Sherbrooke, Qc, Canada.
| | - Frédéric-Simon Hould
- Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Qc, Canada. .,Departement of surgery, Université Laval, Québec, Qc, Canada.
| | - Yohan Bossé
- Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Qc, Canada. .,Department of Molecular Medicine, Université Laval, Quebec, Qc, Canada.
| | - Denis Richard
- Institut universitaire de cardiologie et de pneumologie de Québec (CRIUCPQ), Université Laval, Québec, Qc, Canada. .,Department of Molecular Medicine, Université Laval, Quebec, Qc, Canada. .,Chaire de Recherche Merck Frosst/IRSC Research Chair on Obesity, Québec, Qc, Canada.
| | - Emile Levy
- Department of Nutrition, Université de Montréal and Research center of CHU Sainte-Justine, 3175 Côte Ste-Catherine, Montréal, Qc, Canada. .,JA. deSève Research Chair in nutrition, Montréal, Qc, Canada.
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Xiao C, Dash S, Morgantini C, Adeli K, Lewis GF. Gut Peptides Are Novel Regulators of Intestinal Lipoprotein Secretion: Experimental and Pharmacological Manipulation of Lipoprotein Metabolism. Diabetes 2015; 64:2310-8. [PMID: 26106188 DOI: 10.2337/db14-1706] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Individuals with metabolic syndrome and frank type 2 diabetes are at increased risk of atherosclerotic cardiovascular disease, partially due to the presence of lipid and lipoprotein abnormalities. In these conditions, the liver and intestine overproduce lipoprotein particles, exacerbating the hyperlipidemia of fasting and postprandial states. Incretin-based, antidiabetes therapies (i.e., glucagon-like peptide [GLP]-1 receptor agonists and dipeptidyl peptidase-4 inhibitors) have proven efficacy for the treatment of hyperglycemia. Evidence is accumulating that these agents also improve fasting and postprandial lipemia, the latter more significantly than the former. In contrast, the gut-derived peptide GLP-2, cosecreted from intestinal L cells with GLP-1, has recently been demonstrated to enhance intestinal lipoprotein release. Understanding the roles of these emerging regulators of intestinal lipoprotein secretion may offer new insights into the regulation of intestinal lipoprotein assembly and secretion and provide new opportunities for devising novel strategies to attenuate hyperlipidemia, with the potential for cardiovascular disease reduction.
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Affiliation(s)
- Changting Xiao
- Departments of Medicine and Physiology and Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Satya Dash
- Departments of Medicine and Physiology and Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Cecilia Morgantini
- Departments of Medicine and Physiology and Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Khosrow Adeli
- Program in Molecular Structure & Function, Research Institute, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Gary F Lewis
- Departments of Medicine and Physiology and Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
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Abstract
Dietary lipids are efficiently absorbed by the small intestine, incorporated into triglyceride-rich lipoproteins (chylomicrons), and transported in the circulation to various tissues. Intestinal lipid absorption and mobilization and chylomicron synthesis and secretion are highly regulated processes. Elevated chylomicron production rate contributes to the dyslipidemia seen in common metabolic disorders such as insulin-resistant states and type 2 diabetes and likely increases the risk for atherosclerosis seen in these conditions. An in-depth understanding of the regulation of chylomicron production may provide leads for the development of drugs that could be of therapeutic utility in the prevention of dyslipidemia and atherosclerosis. Chylomicron secretion is subject to regulation by various factors, including diet, body weight, genetic variants, hormones, nutraceuticals, medications, and emerging interventions such as bariatric surgical procedures. In this review we discuss the regulation of chylomicron production, mechanisms that underlie chylomicron dysregulation, and potential avenues for future research.
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Affiliation(s)
- Satya Dash
- Departments of Medicine and Physiology and the Banting & Best Diabetes Centre, University of Toronto, Toronto, Ontario, M5G 2C4 Canada;
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Laguna-Camacho A, Alonso-Barreto AS, Mendieta-Zerón H. Direct effects of fatty meals and adiposity on oxidised low-density lipoprotein. Obes Res Clin Pract 2015; 9:298-300. [DOI: 10.1016/j.orcp.2015.03.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 03/19/2015] [Indexed: 02/08/2023]
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Abstract
Cardiovascular disease is a major cause of morbidity and mortality in patients with type 2 diabetes mellitus, with a two- to fourfold increase in cardiovascular disease risk compared with non-diabetic individuals. Abnormalities in lipid metabolism that are observed in the context of type 2 diabetes are among the major factors contributing to an increased cardiovascular risk. Diabetic dyslipidaemia includes not only quantitative lipoprotein abnormalities, but also qualitative and kinetic abnormalities that, together, result in a shift towards a more atherogenic lipid profile. The primary quantitative lipoprotein abnormalities are increased triacylglycerol (triglyceride) levels and decreased HDL-cholesterol levels. Qualitative lipoprotein abnormalities include an increase in large, very low-density lipoprotein subfraction 1 (VLDL1) and small, dense LDLs, as well as increased triacylglycerol content of LDL and HDL, glycation of apolipoproteins and increased susceptibility of LDL to oxidation. The main kinetic abnormalities are increased VLDL1 production, decreased VLDL catabolism and increased HDL catabolism. In addition, even though LDL-cholesterol levels are typically normal in patients with type 2 diabetes, LDL particles show reduced turnover, which is potentially atherogenic. Although the pathophysiology of diabetic dyslipidaemia is not fully understood, the insulin resistance and relative insulin deficiency observed in patients with type 2 diabetes are likely to contribute to these lipid changes, as insulin plays an important role in regulating lipid metabolism. In addition, some adipocytokines, such as adiponectin or retinol-binding protein 4, may also contribute to the development of dyslipidaemia in patients with type 2 diabetes.
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Affiliation(s)
- Bruno Vergès
- Service Endocrinologie, Diabétologie et Maladies Métaboliques, Hôpital du Bocage, 2 bd Maréchal de Lattre de Tassigny, 21000, Dijon, France,
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Abstract
Hypertriglyceridemia (HTG) is a highly prevalent condition that is associated with increased cardiovascular disease risk. HTG may arise as a result of defective metabolism of triglyceride-rich lipoproteins and their remnants, ie, impaired clearance, or increased production, or both. Current categorization of HTG segregates primary and secondary cases, implying genetic and nongenetic causes for each category. Many common and rare variants of the genes encoding factors involved in these pathways have been identified. Although monogenic forms of HTG do occur, most cases are polygenic and often coexist with nongenetic conditions. Cumulative, multiple genetic variants can increase the risks for HTG, whereas environmental and lifestyle factors can force expression of a dyslipidemic phenotype in a genetically susceptible person. HTG states are therefore best viewed as a complex phenotype resulting from the interaction of cumulated multiple susceptibility genes and environmental stressors. In view of the heterogeneity of the HTG states, the absence of a unifying metabolic or genetic abnormality, overlap with the metabolic syndrome and other features of insulin resistance, and evidence in some patients that accumulation of numerous small-effect genetic variants determines whether an individual is susceptible to HTG only or to HTG plus elevated low-density lipoprotein cholesterol, we propose that the diagnosis of primary HTG and further delineation of familial combined hyperlipidemia from familial HTG is neither feasible nor clinically relevant at the present time. The hope is that with greater understanding of genetic and environmental causes and their interaction, therapy can be intelligently targeted in the future.
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Affiliation(s)
- Gary F Lewis
- Departments of Medicine and Physiology and the Banting and Best Diabetes Centre (G.F.L., C.X.), University of Toronto, Toronto, Ontario, Canada M5G 2C4; and Robarts Research Institute (R.A.H.), Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada N6A 5B7
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Yue JTY, Abraham MA, LaPierre MP, Mighiu PI, Light PE, Filippi BM, Lam TKT. A fatty acid-dependent hypothalamic–DVC neurocircuitry that regulates hepatic secretion of triglyceride-rich lipoproteins. Nat Commun 2015; 6:5970. [DOI: 10.1038/ncomms6970] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 11/26/2014] [Indexed: 12/31/2022] Open
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Tremblay AJ, Lamarche B, Kelly I, Charest A, Lépine MC, Droit A, Couture P. Effect of sitagliptin therapy on triglyceride-rich lipoprotein kinetics in patients with type 2 diabetes. Diabetes Obes Metab 2014; 16:1223-9. [PMID: 25059982 DOI: 10.1111/dom.12359] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 07/17/2014] [Accepted: 07/21/2014] [Indexed: 02/06/2023]
Abstract
AIM To investigate the effects of sitagliptin therapy on the kinetics of triglyceride-rich lipoprotein (TRL) apolipoprotein (apo)B-48, VLDL apoB-100, apoE and apoC-III in patients with type 2 diabetes. METHODS Twenty-two subjects with type 2 diabetes were recruited in this double-blind crossover study, during which the subjects received sitagliptin (100 mg/day) or placebo for a 6-week period each. At the end of each phase of treatment, the in vivo kinetics of the different apolipoproteins were assessed using a primed-constant infusion of l-[5,5,5-D3]leucine for 12 h, with the participants in a constantly fed state. RESULTS Sitagliptin therapy significantly reduced fasting plasma triglyceride (-15.4%, p = 0.03), apoB-48 (-16.3%, p = 0.03) and free fatty acid concentrations (-9.5%, p = 0.04), as well as plasma HbA1c (placebo: 7.0% ± 0.8 vs. sitagliptin: 6.6% ± 0.7, p < 0.0001) and plasma glucose levels (-13.5%, p = 0.001), without any significant effect on insulin levels. Kinetic results showed that treatment with sitagliptin significantly reduced the pool size of TRL apoB-48 by -20.8% (p = 0.03), paralleled by a reduction in the production rate of these particles (-16.0%, p = 0.03). The VLDL apoB-100 pool size was also significantly decreased by sitagliptin therapy (-9.3%, p = 0.03), mainly because of a reduction in the hepatic secretion of these lipoproteins, although this difference did not reach statistical significance (-9.2%, p = 0.06). CONCLUSIONS Treatment with sitagliptin for 6 weeks reduced triglyceride-rich apoB-containing lipoprotein levels by reducing the synthesis of these particles.
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Affiliation(s)
- A J Tremblay
- Lipid Research Centre, Centre Hospitalier de l'Université Laval (CHUL) Research Centre, Quebec City, QC, Canada; Institute of Nutrition and Functional Foods, Laval University, Quebec City, QC, Canada
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Dash S, Xiao C, Morgantini C, Connelly PW, Patterson BW, Lewis GF. Glucagon-like peptide-2 regulates release of chylomicrons from the intestine. Gastroenterology 2014; 147:1275-1284.e4. [PMID: 25173752 PMCID: PMC4316201 DOI: 10.1053/j.gastro.2014.08.037] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 08/19/2014] [Accepted: 08/22/2014] [Indexed: 01/08/2023]
Abstract
BACKGROUND & AIMS The intestine efficiently incorporates and rapidly secretes dietary fat as chylomicrons (lipoprotein particles comprising triglycerides, phospholipids, cholesterol, and proteins) that contain the apolipoprotein isoform apoB-48. The gut can store lipids for many hours after their ingestion, and release them in chylomicrons in response to oral glucose, sham feeding, or unidentified stimuli. The gut hormone glucagon-like peptide-2 (GLP-2) facilitates intestinal absorption of lipids, but its role in chylomicron secretion in human beings is unknown. METHODS We performed a randomized, single-blind, cross-over study, with 2 study visits 4 weeks apart, to assess the effects of GLP-2 administration on triglyceride-rich lipoprotein (TRL) apoB-48 in 6 healthy men compared with placebo. Subjects underwent constant intraduodenal feeding, with a pancreatic clamp and primed constant infusion of deuterated leucine. In a separate randomized, single-blind, cross-over validation study, 6 additional healthy men ingested a high-fat meal containing retinyl palmitate and were given either GLP-2 or placebo 7 hours later with measurement of TRL triglyceride, TRL retinyl palmitate, and TRL apoB-48 levels. RESULTS GLP-2 administration resulted in a rapid (within 30 minutes) and transient increase in the concentration of TRL apoB-48, compared with placebo (P = .03). Mathematic modeling of stable isotope enrichment and the mass of the TRL apoB-48 suggested that the increase resulted from the release of stored, presynthesized apoB-48 from the gut. In the validation study, administration of GLP-2 at 7 hours after the meal, in the absence of additional food intake, robustly increased levels of TRL triglycerides (P = .007), TRL retinyl palmitate (P = .002), and TRL apoB-48 (P = .04) compared with placebo. CONCLUSIONS Administration of GLP-2 to men causes the release of chylomicrons that comprise previously synthesized and stored apoB-48 and lipids. This transiently increases TRL apoB-48 levels compared with placebo. Clinical trials number at www.clinicaltrials.gov: NCT 01958775.
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Affiliation(s)
- Satya Dash
- Department of Medicine, Department of Physiology, Banting and Best Diabetes Centre, Canada
,Division of Endocrinology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Changting Xiao
- Department of Medicine, Department of Physiology, Banting and Best Diabetes Centre, Canada
,Division of Endocrinology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Cecilia Morgantini
- Department of Medicine, Department of Physiology, Banting and Best Diabetes Centre, Canada
,Division of Endocrinology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Philip W. Connelly
- Division of Endocrinology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
,Keenan Research Centre for Biomedical Science of St. Michael’s Hospital, Toronto, Ontario, Canada
| | - Bruce W. Patterson
- Center for Human Nutrition, Department of Internal Medicine, Division of Geriatrics and Nutritional Science, Washington University School of Medicine, St. Louis, Missouri
| | - Gary F. Lewis
- Department of Medicine, Department of Physiology, Banting and Best Diabetes Centre, Canada
,Division of Endocrinology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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Xiao C, Dash S, Morgantini C, Patterson BW, Lewis GF. Sitagliptin, a DPP-4 inhibitor, acutely inhibits intestinal lipoprotein particle secretion in healthy humans. Diabetes 2014; 63:2394-401. [PMID: 24584549 PMCID: PMC4066342 DOI: 10.2337/db13-1654] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The dipeptidyl peptidase-4 inhibitor sitagliptin, an antidiabetic agent, which lowers blood glucose levels, also reduces postprandial lipid excursion after a mixed meal. The underlying mechanism of this effect, however, is not clear. This study examined the production and clearance of triglyceride-rich lipoprotein particles from the liver and intestine in healthy volunteers in response to a single oral dose of sitagliptin. Using stable isotope tracer techniques and with control of pancreatic hormone levels, the kinetics of lipoprotein particles of intestinal and hepatic origin were measured. Compared with placebo, sitagliptin decreased intestinal lipoprotein concentration by inhibiting particle production, independent of changes in pancreatic hormones, and circulating levels of glucose and free fatty acids. Fractional clearance of particles of both intestinal and hepatic origin, and production of particles of hepatic origin, were not affected. This pleiotropic effect of sitagliptin may explain the reduction in postprandial lipemia seen in clinical trials of this agent and may provide metabolic benefits beyond lowering of glucose levels.
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Affiliation(s)
- Changting Xiao
- Departments of Medicine and Physiology, Division of Endocrinology and Metabolism, Banting and Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Satya Dash
- Departments of Medicine and Physiology, Division of Endocrinology and Metabolism, Banting and Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Cecilia Morgantini
- Departments of Medicine and Physiology, Division of Endocrinology and Metabolism, Banting and Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
| | - Bruce W Patterson
- Center for Human Nutrition, Department of Internal Medicine, Division of Geriatrics and Nutritional Science, Washington University School of Medicine, St. Louis, MO
| | - Gary F Lewis
- Departments of Medicine and Physiology, Division of Endocrinology and Metabolism, Banting and Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
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Jacome-Sosa MM, Parks EJ. Fatty acid sources and their fluxes as they contribute to plasma triglyceride concentrations and fatty liver in humans. Curr Opin Lipidol 2014; 25:213-20. [PMID: 24785962 DOI: 10.1097/mol.0000000000000080] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE OF REVIEW Different sources of fatty acids (FA) used for VLDL-triglyceride synthesis include dietary FA that clear to the liver via chylomicron uptake, FA synthesized de novo in the liver from carbohydrates, nonesterified fatty acids derived from adipose tissue, nonesterified fatty acids derived from the spillover of chylomicron-triglyceride in the fasted and fed states, and FA stored in liver lipid droplets. RECENT FINDINGS Data have amassed on the contributions of each of these sources to liver-triglyceride accrual, VLDL-triglyceride synthesis, and hypertriglyceridemia. Discussed here is the timing of use of FA from each of these sources for synthesis of VLDL-triglyceride. Secondly, as all of these FA sources have been shown to contribute significantly to nonalcoholic fatty liver disease (NAFLD), data are presented demonstrating how poor handling of FA and glucose in the periphery can contribute to NAFLD. Lastly, we highlight how the stress of excess FA availability on the liver can be corrected by reduction of dietary intake of sugars and fats, weight loss, and increased physical activity. SUMMARY A better understanding of how lifestyle factors improve FA flux will aid in the development of improved treatments for the devastating condition of NAFLD.
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Affiliation(s)
- M Miriam Jacome-Sosa
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri, USA
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Tucker RM, Mattes RD, Running CA. Mechanisms and effects of "fat taste" in humans. Biofactors 2014; 40:313-26. [PMID: 24591077 DOI: 10.1002/biof.1162] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 02/18/2014] [Indexed: 12/11/2022]
Abstract
Evidence supporting a "taste" cue from fat in the oral cavity continues to accrue. The proposed stimuli for fat taste, non-esterified fatty acids (NEFA), are released from food through hydrolytic rancidity and lipase activity derived from foods or saliva. NEFA must then be released from the food matrix, negotiate the aqueous environment to reach taste cell surfaces, and interact with receptors such as CD36 and GPR120 or diffuse across cell membranes to initiate a taste signal. Knowledge of these processes in non-gustatory tissues should inform understanding of taste responses to NEFA. Additionally, downstream effects of oral triglyceride exposure have been observed in numerous studies. Data specific to effects of NEFA versus triglyceride are scarce, but modified sham feeding trials with triglyceride document cephalic phase responses including elevations in serum lipids and insulin as well as potential, but debated, effects on gut peptides, appetite, and thermogenesis. In this review, we highlight the mechanisms by which NEFA migrate to and interact with taste cells, and then we examine physiological responses to oral fat exposure.
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Affiliation(s)
- Robin M Tucker
- Department of Nutrition Science, Purdue University, West Lafayette, IN, USA
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Klop B, Verseyden C, Ribalta J, Salazar J, Masana L, Cabezas MC. MTP gene polymorphisms and postprandial lipemia in familial combined hyperlipidemia: Effects of treatment with atorvastatin. CLINICA E INVESTIGACION EN ARTERIOSCLEROSIS 2014; 26:49-57. [DOI: 10.1016/j.arteri.2013.11.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 11/14/2013] [Accepted: 11/18/2013] [Indexed: 10/25/2022]
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Xiao C, Dash S, Morgantini C, Lewis GF. New and emerging regulators of intestinal lipoprotein secretion. Atherosclerosis 2014; 233:608-615. [PMID: 24534456 DOI: 10.1016/j.atherosclerosis.2013.12.047] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Revised: 12/12/2013] [Accepted: 12/31/2013] [Indexed: 12/25/2022]
Abstract
Overproduction of hepatic apoB100-containing VLDL particles has been well documented in animal models and in humans with insulin resistance such as the metabolic syndrome and type 2 diabetes, and contributes to the typical dyslipidemia of these conditions. In addition, postprandial hyperlipidemia and elevated plasma concentrations of intestinal apoB48-containing chylomicron and chylomicron remnant particles have been demonstrated in insulin resistant states. Intestinal lipoprotein production is primarily determined by the amount of fat ingested and absorbed. Until approximately 10 years ago, however, relatively little attention was paid to the role of the intestine itself in regulating the production of triglyceride-rich lipoproteins (TRL) and its dysregulation in pathological states such as insulin resistance. We and others have shown that insulin resistant animal models and humans are characterized by overproduction of intestinal apoB48-containing lipoproteins. Whereas various factors are known to regulate hepatic lipoprotein particle production, less is known about factors that regulate the production of intestinal lipoprotein particles. Monosacharides, plasma free fatty acids (FFA), resveratrol, intestinal peptides (e.g. GLP-1 and GLP-2), and pancreatic hormones (e.g. insulin) have recently been shown to be important regulators of intestinal lipoprotein secretion. Available evidence in humans and animal models strongly supports the concept that the small intestine is not merely an absorptive organ but rather plays an active role in regulating the rate of production of chylomicrons in fed and fasting states. Metabolic signals in insulin resistance and type 2 diabetes and in some cases an aberrant intestinal response to these factors contribute to the enhanced formation and secretion of TRL. Understanding the regulation of intestinal lipoprotein production is imperative for the development of new therapeutic strategies for the prevention and treatment of dyslipidemia. Here we review recent developments in this field and present evidence that intestinal lipoprotein production is a process with metabolic plasticity and that modulation of intestinal lipoprotein secretion may be a feasible therapeutic strategy in the treatment of dyslipidemia and possibly prevention of atherosclerosis.
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Affiliation(s)
- Changting Xiao
- Department of Medicine, University of Toronto, Canada; Department of Physiology, University of Toronto, Canada; Banting and Best Diabetes Centre, Toronto General Hospital, 200 Elizabeth Street, EN12-218, Toronto, Ontario M5G 2C4, Canada
| | - Satya Dash
- Department of Medicine, University of Toronto, Canada; Department of Physiology, University of Toronto, Canada; Banting and Best Diabetes Centre, Toronto General Hospital, 200 Elizabeth Street, EN12-218, Toronto, Ontario M5G 2C4, Canada
| | - Cecilia Morgantini
- Department of Medicine, University of Toronto, Canada; Department of Physiology, University of Toronto, Canada; Banting and Best Diabetes Centre, Toronto General Hospital, 200 Elizabeth Street, EN12-218, Toronto, Ontario M5G 2C4, Canada
| | - Gary F Lewis
- Department of Medicine, University of Toronto, Canada; Department of Physiology, University of Toronto, Canada; Banting and Best Diabetes Centre, Toronto General Hospital, 200 Elizabeth Street, EN12-218, Toronto, Ontario M5G 2C4, Canada.
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Shojaee-Moradie F, Ma Y, Lou S, Hovorka R, Umpleby AM. Prandial hypertriglyceridemia in metabolic syndrome is due to an overproduction of both chylomicron and VLDL triacylglycerol. Diabetes 2013; 62:4063-9. [PMID: 23990358 PMCID: PMC3837057 DOI: 10.2337/db13-0935] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The aim was to determine whether fed VLDL and chylomicron (CM) triacylglycerol (TAG) production rates are elevated in metabolic syndrome (MetS). Eight men with MetS (BMI 29.7 ± 1.1) and eight lean age-matched healthy men (BMI 23.1 ± 0.4) were studied using a frequent feeding protocol. After 4 h of feeding, an intravenous bolus of (2)H5-glycerol was administered to label VLDL1, VLDL2, and TAG. (13)C-glycerol tripalmitin was administered orally as an independent measure of CM TAG metabolism. Hepatic and intestinal lipoproteins were separated by an immunoaffinity method. In MetS, fed TAG and the increment in TAG from fasting to feeding were higher (P = 0.03 and P = 0.04, respectively) than in lean men. Fed CM, VLDL1, and VLDL2 TAG pool sizes were higher (P = 0.006, P = 0.03, and P < 0.02, respectively), and CM, VLDL1, and VLDL2 TAG production rates were higher (P < 0.002, P < 0.05, and P = 0.06, respectively) than in lean men. VLDL1, VLDL2, and CM TAG clearance rates were not different between groups. In conclusion, prandial hypertriglyceridemia in men with MetS was due to an increased production rate of both VLDL and CM TAG. Since both groups received identical meals, this suggests that in MetS the intestine is synthesizing more TAG de novo for export in CMs.
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Affiliation(s)
- Fariba Shojaee-Moradie
- Diabetes and Metabolic Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - Yuying Ma
- Diabetes and Metabolic Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - Shaoying Lou
- Diabetes and Metabolic Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
| | - Roman Hovorka
- Diabetes Modelling Group, Institute of Metabolic Science, University of Cambridge, Cambridge, U.K
| | - A. Margot Umpleby
- Diabetes and Metabolic Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, U.K
- Corresponding author: A. Margot Umpleby,
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Couture P, Tremblay AJ, Kelly I, Lemelin V, Droit A, Lamarche B. Key intestinal genes involved in lipoprotein metabolism are downregulated in dyslipidemic men with insulin resistance. J Lipid Res 2013; 55:128-37. [PMID: 24142110 DOI: 10.1194/jlr.m040071] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Insulin resistance (IR) is associated with elevated plasma levels of triglyceride-rich lipoproteins (TRLs) of intestinal origin. However, the mechanisms underlying the overaccumulation of apolipoprotein (apo)B-48-containing TRLs in individuals with IR are not yet fully understood. This study examined the relationships between apoB-48-containing TRL kinetics and the expression of key intestinal genes and proteins involved in lipid/lipoprotein metabolism in 14 obese nondiabetic men with IR compared with 10 insulin-sensitive (IS) men matched for waist circumference. The in vivo kinetics of TRL apoB-48 were assessed using a primed-constant infusion of L-[5,5,5-D₃]leucine for 12 h with the participants in a constantly fed state. The expression of key intestinal genes and proteins involved in lipid/lipoprotein metabolism was assessed by performing real-time PCR quantification and LC-MS/MS on duodenal biopsy specimens. The TRL apoB-48 pool size and production rate were 102% (P < 0.0001) and 87% (P = 0.01) greater, respectively, in the men with IR versus the IS men. On the other hand, intestinal mRNA levels of sterol regulatory element binding factor-2, hepatocyte nuclear factor-4α, and microsomal triglyceride transfer protein were significantly lower in the men with IR than in the IS men. These data indicate that IR is associated with intestinal overproduction of lipoproteins and significant downregulation of key intestinal genes involved in lipid/lipoprotein metabolism.
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Affiliation(s)
- Patrick Couture
- Institute of Nutrition and Functional Foods Centre Hospitalier de l'Université Laval (CHUL) Research Centre
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48
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Sun F, Stolinski M, Shojaee-Moradie F, Lou S, Ma Y, Hovorka R, Umpleby AM. A novel method for measuring intestinal and hepatic triacylglycerol kinetics. Am J Physiol Endocrinol Metab 2013; 305:E1041-7. [PMID: 23592484 DOI: 10.1152/ajpendo.00105.2013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This study aimed to 1) develop a method that completely separated hepatic (VLDL1, VLDL2) and intestinal [chylomicron (CM)] lipoproteins and 2) use the method to measure triacylglycerol (TAG) kinetics in these lipoproteins in the fed and fasting state in healthy subjects, using intravenous [²H₅]glycerol as the tracer. An immunoaffinity method that completely separated hepatic and intestinal particles using sequential binding to three antibodies to apolipoprotein B-100 (apoB-100) was established and validated. Six healthy volunteers were studied in a fasted and continuous feeding study (study 1). Five additional healthy volunteers were studied in a continuous feeding study that included an oral [¹³C₃]glycerol tripalmitin tracer (study 2). In both studies, an intravenous bolus of [²H₅]glycerol was administered to label TAG in hepatic and intestinal lipoproteins. In both feeding studies there was sufficient incorporation of the [²H₅]glycerol tracer into the exogenous lipoproteins to enable isotopic enrichment to be measured. In study 2, the oral tracer enrichment in VLDL1 was <5% of CM enrichment 150 min after tracer administration, demonstrating negligible contamination of VLDL1 with apoB-48. Western blotting showed no detectable apoB-100 in CMs. VLDL1 and VLDL2 TAG fractional catabolic rate (FCR) did not differ between feeding and fasting (study 1). There was no difference between CM and VLDL1 TAG FCR in both fed studies. In fed study 2, 47% of the total TAG production rate (CM + VLDL1) was from CM. This methodology may be a useful tool for understanding the abnormalities in postprandial TAG kinetics in metabolic syndrome and type 2 diabetes.
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Affiliation(s)
- Feifei Sun
- Diabetes and Metabolic Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom; and
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Dash S, Xiao C, Morgantini C, Szeto L, Lewis GF. High-dose resveratrol treatment for 2 weeks inhibits intestinal and hepatic lipoprotein production in overweight/obese men. Arterioscler Thromb Vasc Biol 2013; 33:2895-901. [PMID: 24072699 DOI: 10.1161/atvbaha.113.302342] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE Overproduction of hepatic apolipoprotein B (apoB)-100 containing very low-density lipoprotein particles and intestinal apoB-48 containing chylomicrons contributes to hypertriglyceridemia seen in conditions such as obesity and insulin resistance. Some, but not all, preclinical and clinical studies have demonstrated that the polyphenol resveratrol ameliorates insulin resistance and hypertriglyceridemia. Here, we assessed intestinal and hepatic lipoprotein turnover, in humans, after 2 weeks of treatment with resveratrol (1000 mg daily for week 1 followed by 2000 mg daily for week 2) or placebo. APPROACH AND RESULTS Eight overweight or obese individuals with mild hypertriglyceridemia were studied on 2 occasions, 4 to 6 weeks apart, after treatment with resveratrol or placebo in a randomized, double-blinded, crossover study. Steady-state lipoprotein kinetics was assessed in a constant fed state with a primed, constant infusion of deuterated leucine. Resveratrol treatment did not significantly affect insulin sensitivity (homeostasis model of assessment of insulin resistance), fasting or fed plasma triglyceride concentration. Resveratrol reduced apoB-48 production rate by 22% (P=0.007) with no significant effect on fractional catabolic rate. Resveratrol reduced apoB-100 production rate by 27% (P=0.02) and fractional catabolic rate by 26% (P=0.04). CONCLUSIONS These results indicate that 2 weeks of high-dose resveratrol reduces intestinal and hepatic lipoprotein particle production. Long-term studies are needed to evaluate the potential clinical benefits of resveratrol in patients with hypertriglyceridemia, who have increased concentrations of triglyceride-rich lipoprotein apoB-100 and apoB-48. CLINICAL TRIAL REGISTRATION URL www.clinicaltrials.gov. Unique identifier: NCT01451918.
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Affiliation(s)
- Satya Dash
- From the Department of Medicine, Physiology, and the Banting and Best Diabetes Centre, University of Toronto, Ontario, Canada (S.D., C.X., C.M., L.S., G.F.L.); and Scuola Superiore Sant'Anna, Pisa, Italy (C.M.)
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Rol del enterocito en la dislipemia de la resistencia insulínica. ACTA ACUST UNITED AC 2013; 60:179-89. [DOI: 10.1016/j.endonu.2012.06.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Revised: 05/31/2012] [Accepted: 06/04/2012] [Indexed: 01/06/2023]
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