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Vučinić N, Stokić E, Djan I, Obreht D, Veličković N, Stankov K, Djan M. The LRP1 Gene Polymorphism is associated with Increased Risk of Metabolic Syndrome Prevalence in the Serbian Population. Balkan J Med Genet 2017; 20:51-58. [PMID: 28924541 PMCID: PMC5596822 DOI: 10.1515/bjmg-2017-0004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The determination of genetic background in metabolic syndrome (MetS) represents one of the necessary steps to prevent the disorder, thus reducing the cost of medical treatments and helping to design targeted therapy. The study explores the association between individual alleles of the LRP1 gene and the diagnosis of MetS to find correlation between the low-density lipoprotein receptor-related (LRP1) gene polymorphism and each individual anthropometric and biochemical parameter. The study included 93 males and females, aged from 19 to 65, divided into two groups. The genotype of each person was determined from the restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) profile. Results indicated the association of the T allele form of exon 3 LRP1 gene with development and progression of MetS that further pointed out its negative impact on tested anthropometric and biochemical parameters. The presence of the T allele in patients multiplies the chance of occurrence of deviations from the reference values of body mass index (BMI), (4.24-fold) and low-density lipoprotein (LDL) (20.26-fold) compared to C allele carriers. The results showed that T allele presence multiplies the chance (4.76 fold) for the occurrence of MetS in comparison to C allele carriers. Correlation found that the T allele of the LRP1 gene with MetS determinants is not negligible, therefore, the T allele may be considered as a risk factor for MetS development.
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Affiliation(s)
- N Vučinić
- University of Novi Sad, Faculty of Medicine, Department of Pharmacy, Novi Sad, Serbia
| | - E Stokić
- University of Novi Sad, Faculty of Medicine, Department of Pharmacy, Novi Sad, Serbia.,Clinical Center of Vojvodina, Department of Endocrinology, and Metabolic Disorders, Novi Sad, Serbia
| | - I Djan
- University of Novi Sad, Faculty of Medicine, Novi Sad, Serbia.,Institute of Oncology, Department of Radiotherapy, Sremska Kamenica, Serbia
| | - D Obreht
- University of Novi Sad, Faculty of Sciences, Department of Biolgy and Ecology, Novi Sad, Serbia
| | - N Veličković
- University of Novi Sad, Faculty of Sciences, Department of Biolgy and Ecology, Novi Sad, Serbia
| | - K Stankov
- University of Novi Sad, Faculty of Medicine, Department of Biochemistry, Novi Sad, Serbia
| | - M Djan
- University of Novi Sad, Faculty of Sciences, Department of Biolgy and Ecology, Novi Sad, Serbia
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Konaniah ES, Kuhel DG, Basford JE, Weintraub NL, Hui DY. Deficiency of LRP1 in Mature Adipocytes Promotes Diet-Induced Inflammation and Atherosclerosis-Brief Report. Arterioscler Thromb Vasc Biol 2017; 37:1046-1049. [PMID: 28473440 DOI: 10.1161/atvbaha.117.309414] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 04/14/2017] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Mice with adipocyte-specific inactivation of low-density lipoprotein receptor-related protein-1 (LRP1) are resistant to diet-induced obesity and hyperglycemia because of compensatory thermogenic response by muscle. However, the physiological function of LRP1 in mature adipocytes and its role in cardiovascular disease modulation are unknown. This study compared perivascular adipose tissues (PVAT) from wild-type (adLrp1+/+) and adipocyte-specific LRP1 knockout (adLrp1-/-) mice in modulation of atherosclerosis progression. APPROACH AND RESULTS Analysis of adipose tissues from adLrp1+/+ and adLrp1-/- mice after Western diet feeding for 16 weeks revealed that, in comparison to adLrp1+/+ mice, the adipocytes in adLrp1-/- mice were smaller, but their adipose tissues were more inflamed with increased monocyte-macrophage infiltration and inflammatory gene expression. The transplantation of PVAT from chow-fed adLrp1+/+ and adLrp1-/- mice into the area surrounding the carotid arteries of Ldlr-/- mice before feeding the Western diet revealed a contributory role of PVAT toward hypercholesterolemia-induced atherosclerosis. Importantly, recipients of adLrp1-/- PVAT displayed a 3-fold increase in atherosclerosis compared with adLrp1+/+ PVAT recipients. The increased atherosclerosis invoked by LRP1-deficient PVAT was associated with elevated monocyte-macrophage infiltration and inflammatory cytokine expression in the transplanted fat. CONCLUSIONS PVAT provide outside-in signals through the adventitia to modulate atherosclerotic lesion progression in response to hypercholesterolemia. Moreover, adipocytes with LRP1 deficiency are dysfunctional and more inflamed. This latter observation adds the adipose tissue to the list of anatomic sites where LRP1 expression is important to protect against diet-induced atherosclerosis.
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Affiliation(s)
- Eddy S Konaniah
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.)
| | - David G Kuhel
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.)
| | - Joshua E Basford
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.)
| | - Neal L Weintraub
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.)
| | - David Y Hui
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.).
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53
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Roichman A, Kanfi Y, Glazz R, Naiman S, Amit U, Landa N, Tinman S, Stein I, Pikarsky E, Leor J, Cohen HY. SIRT6 Overexpression Improves Various Aspects of Mouse Healthspan. J Gerontol A Biol Sci Med Sci 2017; 72:603-615. [PMID: 27519885 DOI: 10.1093/gerona/glw152] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 07/18/2016] [Indexed: 01/08/2023] Open
Abstract
The extension in human lifespan in the last century results in a significant increase in incidence of age related diseases. It is therefore crucial to identify key factors that control elderly healthspan. Similar to dietary restriction, mice overexpressing the NAD+ dependent protein deacylase SIRT6 (MOSES) live longer and have reduced IGF-1 levels. However, it is as yet unknown whether SIRT6 also affects various healthspan parameters. Here, a range of age related phenotypes was evaluated in MOSES mice. In comparison to their wild-type (WT) littermates, old MOSES mice showed amelioration of a variety of age-related disorders, including: improved glucose tolerance, younger hormonal profile, reduced age-related adipose inflammation and increased physical activity. The increased activity was accompanied with increased muscle AMP-activated protein kinase (AMPK) activity. Altogether, these results indicate that overexpression of SIRT6 in mice retards important aspects of the aging process and suggest SIRT6 to be a potential therapeutic target for the treatment of a set of age-related disorders.
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Affiliation(s)
- Asael Roichman
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Yariv Kanfi
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Renana Glazz
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Shoshana Naiman
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Uri Amit
- Tamman and Neufeld Cardiovascular Research Institute, Sheba Center of Regenerative Medicine, Sheba Medical Center, Tel Aviv University, Israel
| | - Natalie Landa
- Tamman and Neufeld Cardiovascular Research Institute, Sheba Center of Regenerative Medicine, Sheba Medical Center, Tel Aviv University, Israel
| | - Simon Tinman
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Ilan Stein
- The Lautenberg Center for Immunology and Cancer Research, IMRIC, Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Eli Pikarsky
- The Lautenberg Center for Immunology and Cancer Research, IMRIC, Hebrew University Hadassah Medical School, Jerusalem, Israel
| | - Jonathan Leor
- Tamman and Neufeld Cardiovascular Research Institute, Sheba Center of Regenerative Medicine, Sheba Medical Center, Tel Aviv University, Israel
| | - Haim Y Cohen
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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54
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Endothelial LRP1 regulates metabolic responses by acting as a co-activator of PPARγ. Nat Commun 2017; 8:14960. [PMID: 28393867 PMCID: PMC5394236 DOI: 10.1038/ncomms14960] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 02/16/2017] [Indexed: 01/04/2023] Open
Abstract
Low-density lipoprotein receptor-related protein 1 (LRP1) regulates lipid and glucose metabolism in liver and adipose tissue. It is also involved in central nervous system regulation of food intake and leptin signalling. Here we demonstrate that endothelial Lrp1 regulates systemic energy homeostasis. Mice with endothelial-specific Lrp1 deletion display improved glucose sensitivity and lipid profiles combined with increased oxygen consumption during high-fat-diet-induced obesity. We show that the intracellular domain of Lrp1 interacts with the nuclear receptor Pparγ, a central regulator of lipid and glucose metabolism, acting as its transcriptional co-activator in endothelial cells. Therefore, Lrp1 not only acts as an endocytic receptor but also directly participates in gene transcription. Our findings indicate an underappreciated functional role of endothelium in maintaining systemic energy homeostasis.
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Garlapow ME, Everett LJ, Zhou S, Gearhart AW, Fay KA, Huang W, Morozova TV, Arya GH, Turlapati L, St Armour G, Hussain YN, McAdams SE, Fochler S, Mackay TFC. Genetic and Genomic Response to Selection for Food Consumption in Drosophila melanogaster. Behav Genet 2017; 47:227-243. [PMID: 27704301 PMCID: PMC5305434 DOI: 10.1007/s10519-016-9819-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 09/16/2016] [Indexed: 12/21/2022]
Abstract
Food consumption is an essential component of animal fitness; however, excessive food intake in humans increases risk for many diseases. The roles of neuroendocrine feedback loops, food sensing modalities, and physiological state in regulating food intake are well understood, but not the genetic basis underlying variation in food consumption. Here, we applied ten generations of artificial selection for high and low food consumption in replicate populations of Drosophila melanogaster. The phenotypic response to selection was highly asymmetric, with significant responses only for increased food consumption and minimal correlated responses in body mass and composition. We assessed the molecular correlates of selection responses by DNA and RNA sequencing of the selection lines. The high and low selection lines had variants with significantly divergent allele frequencies within or near 2081 genes and 3526 differentially expressed genes in one or both sexes. A total of 519 genes were both genetically divergent and differentially expressed between the divergent selection lines. We performed functional analyses of the effects of RNAi suppression of gene expression and induced mutations for 27 of these candidate genes that have human orthologs and the strongest statistical support, and confirmed that 25 (93 %) affected the mean and/or variance of food consumption.
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Affiliation(s)
- Megan E Garlapow
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695-7614, USA
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Logan J Everett
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695-7614, USA
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
- Initiative for Biological Complexity, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Shanshan Zhou
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695-7614, USA
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
- Initiative for Biological Complexity, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Alexander W Gearhart
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Kairsten A Fay
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Wen Huang
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695-7614, USA
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
- Initiative for Biological Complexity, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Tatiana V Morozova
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Gunjan H Arya
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Lavanya Turlapati
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Genevieve St Armour
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Yasmeen N Hussain
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Sarah E McAdams
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
| | - Sophia Fochler
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA
- School of Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, UK
| | - Trudy F C Mackay
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695-7614, USA.
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695-7614, USA.
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695-7614, USA.
- Initiative for Biological Complexity, North Carolina State University, Raleigh, NC, 27695-7614, USA.
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56
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Au DT, Strickland DK, Muratoglu SC. The LDL Receptor-Related Protein 1: At the Crossroads of Lipoprotein Metabolism and Insulin Signaling. J Diabetes Res 2017; 2017:8356537. [PMID: 28584820 PMCID: PMC5444004 DOI: 10.1155/2017/8356537] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 04/11/2017] [Indexed: 12/30/2022] Open
Abstract
The metabolic syndrome is an escalating worldwide public health concern. Defined by a combination of physiological, metabolic, and biochemical factors, the metabolic syndrome is used as a clinical guideline to identify individuals with a higher risk for type 2 diabetes and cardiovascular disease. Although risk factors for type 2 diabetes and cardiovascular disease have been known for decades, the molecular mechanisms involved in the pathophysiology of these diseases and their interrelationship remain unclear. The LDL receptor-related protein 1 (LRP1) is a large endocytic and signaling receptor that is widely expressed in several tissues. As a member of the LDL receptor family, LRP1 is involved in the clearance of chylomicron remnants from the circulation and has been demonstrated to be atheroprotective. Recently, studies have shown that LRP1 is involved in insulin receptor trafficking and regulation and glucose metabolism. This review summarizes the role of tissue-specific LRP1 in insulin signaling and its potential role as a link between lipoprotein and glucose metabolism in diabetes.
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Affiliation(s)
- Dianaly T. Au
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Dudley K. Strickland
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Selen C. Muratoglu
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD, USA
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- *Selen C. Muratoglu:
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57
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Hernández-Ochoa EO, Llanos P, Lanner JT. The Underlying Mechanisms of Diabetic Myopathy. J Diabetes Res 2017; 2017:7485738. [PMID: 29238729 PMCID: PMC5697129 DOI: 10.1155/2017/7485738] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Accepted: 07/04/2017] [Indexed: 12/25/2022] Open
Affiliation(s)
- Erick O. Hernández-Ochoa
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, USA
| | - Paola Llanos
- Institute for Research in Dental Sciences, Facultad de Odontología, Universidad de Chile, Santiago, Chile
| | - Johanna T. Lanner
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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58
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Xu X, Dou D. The ginseng's fireness is associated with the lowering activity of liver Na(+)-K(+)-ATPase. JOURNAL OF ETHNOPHARMACOLOGY 2016; 190:241-250. [PMID: 27288755 DOI: 10.1016/j.jep.2016.06.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 05/20/2016] [Accepted: 06/07/2016] [Indexed: 06/06/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Ginseng is an herbal medicine used worldwide that possesses a wide range of pharmacological activities. However, its side effects are rarely discussed. The experience of Chinese medicine has revealed that taking ginseng at a high dose chronically can cause fireness, i.e., the ginseng-abuse syndrome. Here, we explored the mechanism of ginseng's fireness by comparing the energy metabolism of mice affected by red ginseng (RG), ginseng (GS), ginseng leaves (GL) and American ginseng (AG), which exhibit different drug properties according to the theory of TCM. MATERIALS AND METHODS KM mice were randomly divided into five groups (n≥30 per group) and administered distilled water or drugs, respectively. Mice receiving RG, GS, or GL received 4.5g/(kgday), while the mice receiving AG received 3g/(kgday). Control mice received distilled water. The duration of exposure for all groups was 31 days. The mice's physical characteristics, such as eye condition, rectal temperature, saliva secretion, urine, stool weight, blood coagulation time and swimming time, were measured at different times after administration. Energy metabolism indexes were measured via TSE phenoMaster/LabMaster animal monitoring system, including the mice' 24h oxygen consumption (VO2), carbon dioxide production (VCO2), heat production (H) and energy expenditure (EE). Biochemical indices were measured by ultraviolet spectrophotometer and microplate reader, including pyruvic acid content in serum and succinate dehydrogenase (SDH) activity, lactate dehydrogenase (LDH) activity, the Na(+)-K(+)-ATPase activity and the content of glycogen in the liver tissue. RESULTS After 31 days of drug administration, mice in the RG and GS groups exhibited obviously more eye secretions, less saliva secretion and less urine. Compared with the control group, the swimming times of mice in the GS, AG and GL groups were significantly prolonged; the clotting time of mice in the GL was extended significantly; VCO2, H and EE of mice in the GS group were obviously increased; Pyruvate content of mice in the RG group showed an initial decrease followed by an increase; SDH activity of mice in the AG and GL groups was significantly inhibited; LDH activity of the mice showed no significant difference among different groups; Na(+)-K(+)-ATP enzyme activity of the RG and GS groups showed up-regulation initially and then down-regulation; the content of hepatic glycogen of mice in the GS and GL groups increased significantly. CONCLUSION The results demonstrated that RG and GS with their warm drug nature could enhance the body's energy metabolism to produce their dryness to the body. The liver Na(+)-K(+)-ATP enzyme activity may be the primary index for indicating the fireness of ginseng. In addition, our results demonstrated that ginseng, especially red ginseng, is not suitable for long time application with a higher dose.
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Affiliation(s)
- Xu Xu
- College of Pharmacy, Liaoning University of Traditional Chinese Medicine, 77 Life one Road, DD Port, Dalian 116600, PR China.
| | - Deqiang Dou
- College of Pharmacy, Liaoning University of Traditional Chinese Medicine, 77 Life one Road, DD Port, Dalian 116600, PR China.
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Hamlin AN, Basford JE, Jaeschke A, Hui DY. LRP1 Protein Deficiency Exacerbates Palmitate-induced Steatosis and Toxicity in Hepatocytes. J Biol Chem 2016; 291:16610-9. [PMID: 27317662 DOI: 10.1074/jbc.m116.717744] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Indexed: 01/21/2023] Open
Abstract
LRP1 (LDL receptor-related protein-1) is a ubiquitous receptor with both cell signaling and ligand endocytosis properties. In the liver, LRP1 serves as a chylomicron remnant receptor and also participates in the transport of extracellular cathepsin D to the lysosome for prosaposin activation. The current study showed that in comparison with wild type mice, hepatocyte-specific LRP1 knock-out (hLrp1(-/-)) mice were more susceptible to fasting-induced lipid accumulation in the liver. Primary hepatocytes isolated from hLrp1(-/-) mice also accumulated more intracellular lipids and experienced higher levels of endoplasmic reticulum (ER) stress after palmitate treatment compared with similarly treated hLrp1(+/+) hepatocytes. Palmitate-treated hLrp1(-/-) hepatocytes displayed similar LC3-II levels, but the levels of p62 were elevated in comparison with palmitate-treated hLrp1(+/+) hepatocytes, suggesting that the elevated lipid accumulation in LRP1-defective hepatocytes was not due to defects in autophagosome formation but was due to impairment of lipophagic lipid hydrolysis in the lysosome. Additional studies showed increased palmitate-induced oxidative stress, mitochondrial and lysosomal permeability, and cell death in hLrp1(-/-) hepatocytes. Importantly, the elevated cell death and ER stress observed in hLrp1(-/-) hepatocytes were abrogated by E64D treatment, whereas inhibiting ER stress diminished cell death but not lysosomal permeabilization. Taken together, these results documented that LRP1 deficiency in hepatocytes promotes lipid accumulation and lipotoxicity through lysosomal-mitochondrial permeabilization and ER stress that ultimately result in cell death. Hence, LRP1 dysfunction may be a major risk factor in fatty liver disease progression.
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Affiliation(s)
| | - Joshua E Basford
- Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| | - Anja Jaeschke
- Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| | - David Y Hui
- Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
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Ding Y, Xian X, Holland WL, Tsai S, Herz J. Low-Density Lipoprotein Receptor-Related Protein-1 Protects Against Hepatic Insulin Resistance and Hepatic Steatosis. EBioMedicine 2016; 7:135-45. [PMID: 27322467 PMCID: PMC4913705 DOI: 10.1016/j.ebiom.2016.04.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 03/31/2016] [Accepted: 04/01/2016] [Indexed: 11/15/2022] Open
Abstract
Low-density lipoprotein receptor-related protein-1 (LRP1) is a multifunctional uptake receptor for chylomicron remnants in the liver. In vascular smooth muscle cells LRP1 controls reverse cholesterol transport through platelet-derived growth factor receptor β (PDGFR-β) trafficking and tyrosine kinase activity. Here we show that LRP1 regulates hepatic energy homeostasis by integrating insulin signaling with lipid uptake and secretion. Somatic inactivation of LRP1 in the liver (hLRP1KO) predisposes to diet-induced insulin resistance with dyslipidemia and non-alcoholic hepatic steatosis. On a high-fat diet, hLRP1KO mice develop a severe Metabolic Syndrome secondary to hepatic insulin resistance, reduced expression of insulin receptors on the hepatocyte surface and decreased glucose transporter 2 (GLUT2) translocation. While LRP1 is also required for efficient cell surface insulin receptor expression in the absence of exogenous lipids, this latent state of insulin resistance is unmasked by exposure to fatty acids. This further impairs insulin receptor trafficking and results in increased hepatic lipogenesis, impaired fatty acid oxidation and reduced very low density lipoprotein (VLDL) triglyceride secretion. Hepatic LRP1 deficiency in a mouse model (hLRP1KO) predisposes to diet-induced insulin resistance, dyslipidemia, and obesity. Insulin resistance in the hLRP1KO mouse results from reduced cell surface expression of insulin receptor (IR) and impaired translocation of glucose transporter 2 (GLUT2). Excess fatty acids in hLRP1KO mice shift hepatic fatty acid metabolism from an oxidative to a synthetic state, resulting in hepatic steatosis.
LRP1 is a multifunctional transmembrane receptor with essential functions in lipoprotein metabolism and subcellular receptor tyrosine kinase trafficking. A mouse model of hepatic LRP1 deficiency integrates the hallmark findings in Metabolic Syndrome - insulin resistance, dyslipidemia, and hepatic steatosis - with impaired glucose metabolism and altered hepatic fatty acid metabolism as a consequence of reduced insulin receptor trafficking and signaling. These findings underscore the central role of LRP1 in overall energy homeostasis, and specifically liver glucose and fatty acid metabolism.
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Affiliation(s)
- Yinyuan Ding
- Department of Molecular Genetics, UT Southwestern Medical Center, Dallas, TX 75390, USA; Center for Translational Neurodegeneration Research, UT Southwestern Medical Center, Dallas, TX 75390, USA; Key Laboratory of Medical Electrophysiology, Ministry of Education of China, China; Institute of Cardiovascular Research, Sichuan Medical University, Luzhou 646000, China
| | - Xunde Xian
- Department of Molecular Genetics, UT Southwestern Medical Center, Dallas, TX 75390, USA; Center for Translational Neurodegeneration Research, UT Southwestern Medical Center, Dallas, TX 75390, USA.
| | - William L Holland
- Department of Internal Medicine, Touchstone Diabetes Center, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shirling Tsai
- Department of Surgery, UT Southwestern Medical Center, Dallas, TX 75390, USA; Dallas VA Medical Center, Dallas, TX 75216, USA
| | - Joachim Herz
- Department of Molecular Genetics, UT Southwestern Medical Center, Dallas, TX 75390, USA; Center for Translational Neurodegeneration Research, UT Southwestern Medical Center, Dallas, TX 75390, USA; Department of Neuroscience, UT Southwestern Medical Center, Dallas, TX 75390, USA; Department of Neurology and Neurotherapeutics, UT Southwestern Medical Center, Dallas, TX 75390, USA.
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Circulating soluble low-density lipoprotein receptor-related protein 1 (sLRP1) concentration is associated with hypercholesterolemia: A new potential biomarker for atherosclerosis. Int J Cardiol 2015; 201:20-9. [DOI: 10.1016/j.ijcard.2015.07.085] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Revised: 06/22/2015] [Accepted: 07/29/2015] [Indexed: 11/22/2022]
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62
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Ke B, Zhao Z, Ye X, Gao Z, Manganiello V, Wu B, Ye J. Inactivation of NF-κB p65 (RelA) in Liver Improves Insulin Sensitivity and Inhibits cAMP/PKA Pathway. Diabetes 2015; 64:3355-62. [PMID: 26038580 PMCID: PMC4587638 DOI: 10.2337/db15-0242] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Accepted: 05/20/2015] [Indexed: 01/07/2023]
Abstract
The transcription factor nuclear factor-κB (NF-κB) mediates inflammation and stress signals in cells. To test NF-κB in the control of hepatic insulin sensitivity, we inactivated NF-κB in the livers of C57BL/6 mice through deletion of the p65 gene, which was achieved by crossing floxed-p65 and Alb-cre mice to generate L-p65-knockout (KO) mice. KO mice did not exhibit any alterations in growth, reproduction, and body weight while on a chow diet. However, the mice on a high-fat diet (HFD) exhibited an improvement in systemic insulin sensitivity. Hepatic insulin sensitivity was enhanced as indicated by increased pyruvate tolerance, Akt phosphorylation, and decreased gene expression in hepatic gluconeogenesis. In the liver, a decrease in intracellular cAMP was observed with decreased CREB phosphorylation. Cyclic nucleotide phosphodiesterase-3B (PDE3B), a cAMP-degrading enzyme, was increased in mRNA and protein as a result of the absence of NF-κB activity. NF-κB was found to inhibit PDE3B transcription through three DNA-binding sites in the gene promoter in response to tumor necrosis factor-α. Body composition, food intake, energy expenditure, and systemic and hepatic inflammation were not significantly altered in KO mice on HFD. These data suggest that NF-κB inhibits hepatic insulin sensitivity by upregulating cAMP through suppression of PDE3B gene transcription.
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Affiliation(s)
- Bilun Ke
- Department of Gastroenterology, Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
| | - Zhiyun Zhao
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
| | - Xin Ye
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
| | - Zhanguo Gao
- Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine in Henan Province, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, China
| | - Vincent Manganiello
- Pulmonary Cardiovascular Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD
| | - Bin Wu
- Department of Gastroenterology, Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jianping Ye
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA
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63
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Garlapow ME, Huang W, Yarboro MT, Peterson KR, Mackay TFC. Quantitative Genetics of Food Intake in Drosophila melanogaster. PLoS One 2015; 10:e0138129. [PMID: 26375667 PMCID: PMC4574202 DOI: 10.1371/journal.pone.0138129] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 08/25/2015] [Indexed: 12/16/2022] Open
Abstract
Food intake is an essential animal activity, regulated by neural circuits that motivate food localization, evaluate nutritional content and acceptance or rejection responses through the gustatory system, and regulate neuroendocrine feedback loops that maintain energy homeostasis. Excess food consumption in people is associated with obesity and metabolic and cardiovascular disorders. However, little is known about the genetic basis of natural variation in food consumption. To gain insights in evolutionarily conserved genetic principles that regulate food intake, we took advantage of a model system, Drosophila melanogaster, in which food intake, environmental conditions and genetic background can be controlled precisely. We quantified variation in food intake among 182 inbred, sequenced lines of the Drosophila melanogaster Genetic Reference Panel (DGRP). We found significant genetic variation in the mean and within-line environmental variance of food consumption and observed sexual dimorphism and genetic variation in sexual dimorphism for both food intake traits (mean and variance). We performed genome wide association (GWA) analyses for mean food intake and environmental variance of food intake (using the coefficient of environmental variation, CVE, as the metric for environmental variance) and identified molecular polymorphisms associated with both traits. Validation experiments using RNAi-knockdown confirmed 24 of 31 (77%) candidate genes affecting food intake and/or variance of food intake, and a test cross between selected DGRP lines confirmed a SNP affecting mean food intake identified in the GWA analysis. The majority of the validated candidate genes were novel with respect to feeding behavior, and many had mammalian orthologs implicated in metabolic diseases.
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Affiliation(s)
- Megan E. Garlapow
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695–7614, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Wen Huang
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695–7614, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Michael T. Yarboro
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Kara R. Peterson
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
| | - Trudy F. C. Mackay
- Program in Genetics, North Carolina State University, Raleigh, NC, 27695–7614, United States of America
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, 27695, United States of America
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, 27695, United States of America
- * E-mail:
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64
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Lasrich D, Bartelt A, Grewal T, Heeren J. Apolipoprotein E promotes lipid accumulation and differentiation in human adipocytes. Exp Cell Res 2015. [DOI: 10.1016/j.yexcr.2015.07.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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65
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Klar J, Schuster J, Khan TN, Jameel M, Mäbert K, Forsberg L, Baig SA, Baig SM, Dahl N. Whole exome sequencing identifies LRP1 as a pathogenic gene in autosomal recessive keratosis pilaris atrophicans. J Med Genet 2015; 52:599-606. [PMID: 26142438 DOI: 10.1136/jmedgenet-2014-102931] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 06/14/2015] [Indexed: 12/28/2022]
Abstract
BACKGROUND Keratosis pilaris atrophicans (KPA) is a group of rare genodermatoses characterised by perifollicular keratosis and inflammation that progresses to atrophy and scars of the facial skin. Keratosis pilaris of extensor areas of limbs is a common associated finding. Most cases with KPA are sporadic and no consistent inheritance pattern has been documented. METHODS A large consanguineous Pakistani pedigree segregating autosomal recessive KPA of a mixed type was subject to autozygosity mapping and whole exome sequencing. Quantification of mRNA and protein levels was performed on fibroblasts from affected individuals. Cellular uptake of the low-density lipoprotein (LDL) receptor-related protein 1 (LRP1) ligand α2-macroglobulin (α(2)M) was quantified using fluorescence confocal microscopy. RESULTS Genetic analyses identified a unique homozygous missense variant (K1245R) in the LRP1 in all affected family members. LRP1 encodes the LRP1, a multifunctional cell surface receptor with endocytic functions that belongs to the LDL receptor family. The LRP1 mRNA and LRP1 protein levels in fibroblasts of affected individuals were markedly reduced when compared with controls. Similarly, the LRP1-mediated cellular uptake of α(2)M was reduced in patient fibroblasts. CONCLUSIONS This is the first report on LRP1 as a pathogenic gene for autosomal recessive KPA and keratosis pilaris. The inflammatory characteristics of the KPA entity in our family suggest a link to the immune-regulatory functions of LRP1.
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Affiliation(s)
- Joakim Klar
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Biomedical Centre, Uppsala, Sweden
| | - Jens Schuster
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Biomedical Centre, Uppsala, Sweden
| | - Tahir Naeem Khan
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Faisalabad, Pakistan
| | - Muhammad Jameel
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Faisalabad, Pakistan
| | - Katrin Mäbert
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Biomedical Centre, Uppsala, Sweden
| | - Lars Forsberg
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Biomedical Centre, Uppsala, Sweden
| | - Shehla Anjum Baig
- Department of Pathology, Children's Hospital, Pakistan Institute of Medical Sciences, (PIMS), Islamabad, Pakistan
| | - Shahid Mahmood Baig
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Pakistan Institute of Engineering and Applied Sciences (PIEAS), Faisalabad, Pakistan
| | - Niklas Dahl
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Biomedical Centre, Uppsala, Sweden
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Habtemichael EN, Alcázar-Román A, Rubin BR, Grossi LR, Belman JP, Julca O, Löffler MG, Li H, Chi NW, Samuel VT, Bogan JS. Coordinated Regulation of Vasopressin Inactivation and Glucose Uptake by Action of TUG Protein in Muscle. J Biol Chem 2015; 290:14454-61. [PMID: 25944897 DOI: 10.1074/jbc.c115.639203] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Indexed: 01/16/2023] Open
Abstract
In adipose and muscle cells, insulin stimulates the exocytic translocation of vesicles containing GLUT4, a glucose transporter, and insulin-regulated aminopeptidase (IRAP), a transmembrane aminopeptidase. A substrate of IRAP is vasopressin, which controls water homeostasis. The physiological importance of IRAP translocation to inactivate vasopressin remains uncertain. We previously showed that in skeletal muscle, insulin stimulates proteolytic processing of the GLUT4 retention protein, TUG, to promote GLUT4 translocation and glucose uptake. Here we show that TUG proteolysis also controls IRAP targeting and regulates vasopressin action in vivo. Transgenic mice with constitutive TUG proteolysis in muscle consumed much more water than wild-type control mice. The transgenic mice lost more body weight during water restriction, and the abundance of renal AQP2 water channels was reduced, implying that vasopressin activity is decreased. To compensate for accelerated vasopressin degradation, vasopressin secretion was increased, as assessed by the cosecreted protein copeptin. IRAP abundance was increased in T-tubule fractions of fasting transgenic mice, when compared with controls. Recombinant IRAP bound to TUG, and this interaction was mapped to a short peptide in IRAP that was previously shown to be critical for GLUT4 intracellular retention. In cultured 3T3-L1 adipocytes, IRAP was present in TUG-bound membranes and was released by insulin stimulation. Together with previous results, these data support a model in which TUG controls vesicle translocation by interacting with IRAP as well as GLUT4. Furthermore, the effect of IRAP to reduce vasopressin activity is a physiologically important consequence of vesicle translocation, which is coordinated with the stimulation of glucose uptake.
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Affiliation(s)
| | - Abel Alcázar-Román
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and
| | - Bradley R Rubin
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06520-8020
| | - Laura R Grossi
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06520-8020
| | - Jonathan P Belman
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06520-8020
| | - Omar Julca
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06520-8020
| | - Michael G Löffler
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and
| | - Hongjie Li
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and
| | - Nai-Wen Chi
- the Veterans Affairs San Diego Healthcare System and Department of Medicine, University of California, San Diego, California 92093, and
| | - Varman T Samuel
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and the Veterans Affairs Medical Center, West Haven, Connecticut 06516
| | - Jonathan S Bogan
- From the Section of Endocrinology and Metabolism, Department of Internal Medicine, and Department of Cell Biology, Yale University School of Medicine, New Haven, Connecticut 06520-8020,
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Gao Z, Zhang J, Henagan TM, Lee JH, Ye X, Wang H, Ye J. P65 inactivation in adipocytes and macrophages attenuates adipose inflammatory response in lean but not in obese mice. Am J Physiol Endocrinol Metab 2015; 308:E496-505. [PMID: 25564477 PMCID: PMC4360014 DOI: 10.1152/ajpendo.00532.2014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
NF-κB induces transcriptional expression of proinflammatory genes and antiapoptotic genes. The two activities of NF-κB remain to be characterized in the mechanism of chronic inflammation in obesity. To address this issue, we inactivated NF-κB in adipose tissue by knocking out p65 (RelA) in mice (F-p65-KO) and examined the inflammation in lean and obese conditions. In the lean condition, KO mice exhibited a reduced inflammation in adipose tissue with a decrease in macrophage infiltration, M1 polarization, and proinflammatory cytokine expression. In the obese condition, KO mice had elevated inflammation with more macrophage infiltration, M1 polarization, and cytokine expression. In the mechanism of enhanced inflammation, adipocytes and macrophages exhibited an increase in cellular apoptosis, which was observed with more formation of crown-like structures (CLS) in fat tissue of KO mice. Body weight, glucose metabolism, and insulin sensitivity were not significantly altered in KO mice under the lean and obese conditions. A modest but significant reduction in body fat mass was observed in KO mice on HFD with an elevation in energy expenditure. The data suggest that in the control of adipose inflammation, NF-κB exhibits different activities in the lean vs. obese condition. NF-κB is required for expression of proinflammatory genes in the lean but not in the obese condition. NF-κB is required for inhibition of apoptosis in the obese condition, in which proinflammation is enhanced by NF-κB inactivation.
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Affiliation(s)
- Zhanguo Gao
- School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, Henan Province, China; Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana
| | - Jin Zhang
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana
| | - Tara M Henagan
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana; Department of Nutrition Science, Purdue University, West Lafayette, Indiana; and
| | - Jong Han Lee
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana
| | - Xin Ye
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana
| | - Hui Wang
- School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, Henan Province, China; Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine in Henan Province, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, China
| | - Jianping Ye
- Antioxidant and Gene Regulation Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, Louisiana;
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68
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Aguilar D, deOgburn RC, Volek JS, Fernandez ML. Cholesterol-induced inflammation and macrophage accumulation in adipose tissue is reduced by a low carbohydrate diet in guinea pigs. Nutr Res Pract 2014; 8:625-31. [PMID: 25489401 PMCID: PMC4252521 DOI: 10.4162/nrp.2014.8.6.625] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 07/21/2014] [Accepted: 07/25/2014] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND/OBJECTIVES The main objective of this study was to evaluate the effects of a high cholesterol (HC) dietary challenge on cholesterol tissue accumulation, inflammation, adipocyte differentiation, and macrophage infiltration in guinea pigs. A second objective was to assess whether macronutrient manipulation would reverse these metabolic alterations. MATERIALS/METHODS Male Hartley guinea pigs (10/group) were assigned to either low cholesterol (LC) (0.04g/100g) or high cholesterol (HC) (0.25g/100g) diets for six weeks. For the second experiment, 20 guinea pigs were fed the HC diet for six weeks and then assigned to either a low carbohydrate (CHO) diet (L-CHO) (10% energy from CHO) or a high CHO diet (H-CHO) (54% CHO) for an additional six weeks. RESULTS Higher concentrations of total (P < 0.005) and free (P < 0.05) cholesterol were observed in both adipose tissue and aortas of guinea pigs fed the HC compared to those in the LC group. In addition, higher concentrations of pro-inflammatory cytokines in the adipose tissue (P < 0.005) and lower concentrations of anti-inflammatory interleukin (IL)-10 were observed in the HC group (P < 0.05) compared to the LC group. Of particular interest, adipocytes in the HC group were smaller in size (P < 0.05) and showed increased macrophage infiltration compared to the LC group. When compared to the H-CHO group, lower concentrations of cholesterol in both adipose and aortas as well as lower concentrations of inflammatory cytokines in adipose tissue were observed in the L-CHO group (P < 0.05). In addition, guinea pigs fed the L-CHO exhibited larger adipose cells and lower macrophage infiltration compared to the H-CHO group. CONCLUSIONS The results of this study strongly suggest that HC induces metabolic dysregulation associated with inflammation in adipose tissue and that L-CHO is more effective than H-CHO in attenuating these detrimental effects.
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Affiliation(s)
- David Aguilar
- Department of Nutritional Sciences, University of Connecticut, 3624 Horsebarn Road Ext, U 4017, Storrs, CT 6269, USA
| | - Ryan C deOgburn
- Department of Nutritional Sciences, University of Connecticut, 3624 Horsebarn Road Ext, U 4017, Storrs, CT 6269, USA
| | - Jeff S Volek
- Department of Nutritional Sciences, University of Connecticut, 3624 Horsebarn Road Ext, U 4017, Storrs, CT 6269, USA. ; Department of Kinesiology, University of Connecticut, USA
| | - Maria Luz Fernandez
- Department of Nutritional Sciences, University of Connecticut, 3624 Horsebarn Road Ext, U 4017, Storrs, CT 6269, USA
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Aguilar D, Fernandez ML. Hypercholesterolemia induces adipose dysfunction in conditions of obesity and nonobesity. Adv Nutr 2014; 5:497-502. [PMID: 25469381 PMCID: PMC4188221 DOI: 10.3945/an.114.005934] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
It is well known that hypercholesterolemia can lead to atherosclerosis and coronary heart disease. Adipose tissue represents an active endocrine and metabolic site, which might be involved in the development of chronic disease. Because adipose tissue is a key site for cholesterol metabolism and the presence of hypercholesterolemia has been shown to induce adipocyte cholesterol overload, it is critical to investigate the role of hypercholesterolemia on normal adipose function. Studies in preadipocytes revealed that cholesterol accumulation can impair adipocyte differentiation and maturation by affecting multiple transcription factors. Hypercholesterolemia has been observed to cause adipocyte hypertrophy, adipose tissue inflammation, and disruption of endocrine function in animal studies. Moreover, these effects can also be observed in obesity-independent conditions as confirmed by clinical trials. In humans, hypercholesterolemia disrupts adipose hormone secretion of visfatin, leptin, and adiponectin, adipokines that play a central role in numerous metabolic pathways and regulate basic physiologic responses such as appetite and satiety. Remarkably, treatment with cholesterol-lowering drugs has been shown to restore adipose tissue endocrine function. In this review the role of hypercholesterolemia on adipose tissue differentiation and maturation, as well as on hormone secretion and physiologic outcomes, in obesity and non–obesity conditions is presented.
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70
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Li YH, Liu L. Apolipoprotein E synthesized by adipocyte and apolipoprotein E carried on lipoproteins modulate adipocyte triglyceride content. Lipids Health Dis 2014; 13:136. [PMID: 25148848 PMCID: PMC4156606 DOI: 10.1186/1476-511x-13-136] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 08/18/2014] [Indexed: 01/02/2023] Open
Abstract
Excessive energy storage of adipose tissue makes contribution to the occurrence and progression of obesity, which accompanies with multiple adverse complications, such as metabolic syndrome, cardiovascular diseases. It is well known that apolipoprotein E, as a component of lipoproteins, performs a key role in maintaining plasma lipoproteins homeostasis. Interestingly, apolipoprotein E is highly expressed in adipocyte and has positive relation with body fat mass. Apolipoprotein E knock-out mice show small fat mass compared to wild type mice. Moreover, adipocyte deficiency in apolipoprotein E shows impaired lipoproeteins internalization and triglyceride accumulation. Apolipopreotein E-deficient lipoproteins can not induce preadipocyte to form round full-lipid adipocyte, whereas apolipoprotein E-containing lipoproteins can. This article mainly reviews the modulation of apolipoprotein E synthesized by adipocyte and apolipoprotein E carried on lipoproteins in adipocyte triglyceride content.
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Affiliation(s)
| | - Ling Liu
- Department of Cardiology, the Second Xiangya Hospital, Central South University, #139 Middle Renmin Road, Changsha, Hunan 410011, PR China.
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Tumour-associated mutant p53 drives the Warburg effect. Nat Commun 2014; 4:2935. [PMID: 24343302 PMCID: PMC3969270 DOI: 10.1038/ncomms3935] [Citation(s) in RCA: 317] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 11/14/2013] [Indexed: 12/11/2022] Open
Abstract
Tumour cells primarily utilize aerobic glycolysis for energy production, a phenomenon known as the Warburg effect. Its mechanism is not well understood. The tumour suppressor gene p53 is frequently mutated in tumours. Many tumour-associated mutant p53 (mutp53) proteins not only lose tumour suppressive function but also gain new oncogenic functions that are independent of wild-type p53, defined as mutp53 gain of function (GOF). Here we show that tumour-associated mutp53 stimulates the Warburg effect in cultured cells and mutp53 knockin mice as a new mutp53 GOF. Mutp53 stimulates the Warburg effect through promoting GLUT1 translocation to the plasma membrane, which is mediated by activated RhoA and its downstream effector ROCK. Inhibition of RhoA/ROCK/GLUT1 signalling largely abolishes mutp53 GOF in stimulating the Warburg effect. Furthermore, inhibition of glycolysis in tumour cells greatly compromises mutp53 GOF in promoting tumorigenesis. Thus, our results reveal a new mutp53 GOF and a mechanism for controlling the Warburg effect.
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72
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Norata GD, Tibolla G, Catapano AL. PCSK9 inhibition for the treatment of hypercholesterolemia: promises and emerging challenges. Vascul Pharmacol 2014; 62:103-11. [PMID: 24924410 DOI: 10.1016/j.vph.2014.05.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 05/31/2014] [Indexed: 10/25/2022]
Abstract
Hypercholesterolemia, is a prominent risk factor for cardiovascular disease (CVD). Undestanding of the biochemical mechanisms that regulate the expression of the low density lipoproteins receptor (LDLR) and the hepatic clearance of LDL cholesterol (LDL-C) paved the way to the statin therapy as the gold standard for CVD prevention. The discovery of proteins that regulate - at a post-translational level - the activity of the LDLR has been a major breakthrough in developing new cholesterol-lowering drugs. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a key modulator of the LDLR degradation in the liver. Genetic studies confirmed that in humans PCSK9 mutations associate with hypercholesterolemia and hypocholesterolemia (gain-of-function or loss-of-function variants respectively). Moreover, PCSK9 is up-regulated by statin treatment and limits the efficacy of these agents. These findings led to the development of PCSK9 inhibitors. Anti-PCSK9 monoclonal antibodies showed encouraging results and are currently being evaluated in phase III clinical trials. The aim of this short review is to describe the new frontier of PCSK9 inhibition in the treatment of hypercholesterolemia. Emphasis here is given to critical emerging issues linked to PCSK9 physiology and pharmacology, which will require future investigation to definitely address the potential of anti-PCSK9 drugs in clinical practice.
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Affiliation(s)
- Giuseppe Danilo Norata
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Italy; Center for the Study of Atherosclerosis, Società Italiana Studio Aterosclerosi, Bassini Hospital, Cinisello Balsamo, Italy
| | - Gianpaolo Tibolla
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Italy; I.R.C.C.S. Multimedica, Milan, Italy
| | - Alberico Luigi Catapano
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Italy; I.R.C.C.S. Multimedica, Milan, Italy.
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Potent Lipolytic Activity of Lactoferrin in Mature Adipocytes. Biosci Biotechnol Biochem 2014; 77:566-71. [DOI: 10.1271/bbb.120817] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Constantinou C, Mpatsoulis D, Natsos A, Petropoulou PI, Zvintzou E, Traish AM, Voshol PJ, Karagiannides I, Kypreos KE. The low density lipoprotein receptor modulates the effects of hypogonadism on diet-induced obesity and related metabolic perturbations. J Lipid Res 2014; 55:1434-47. [PMID: 24837748 DOI: 10.1194/jlr.m050047] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Indexed: 12/21/2022] Open
Abstract
Here, we investigated how LDL receptor deficiency (Ldlr(-/-)) modulates the effects of testosterone on obesity and related metabolic dysfunctions. Though sham-operated Ldlr(-/-) mice fed Western-type diet for 12 weeks became obese and showed disturbed plasma glucose metabolism and plasma cholesterol and TG profiles, castrated mice were resistant to diet-induced obesity and had improved glucose metabolism and reduced plasma TG levels, despite a further deterioration in their plasma cholesterol profile. The effect of hypogonadism on diet-induced weight gain of Ldlr(-/-) mice was independent of ApoE and Lrp1. Indirect calorimetry analysis indicated that hypogonadism in Ldlr(-/-) mice was associated with increased metabolic rate. Indeed, mitochondrial cytochrome c and uncoupling protein 1 expression were elevated, primarily in white adipose tissue, confirming increased mitochondrial metabolic activity due to thermogenesis. Testosterone replacement in castrated Ldlr(-/-) mice for a period of 8 weeks promoted diet-induced obesity, indicating a direct role of testosterone in the observed phenotype. Treatment of sham-operated Ldlr(-/-) mice with the aromatase inhibitor exemestane for 8 weeks showed that the obesity of castrated Ldlr(-/-) mice is independent of estrogens. Overall, our data reveal a novel role of Ldlr as functional modulator of metabolic alterations associated with hypogonadism.
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Affiliation(s)
- Caterina Constantinou
- Department of Medicine, Pharmacology Unit, University of Patras Medical School, Rio Achaias, Greece
| | - Diogenis Mpatsoulis
- Department of Medicine, Pharmacology Unit, University of Patras Medical School, Rio Achaias, Greece
| | - Anastasios Natsos
- Department of Medicine, Pharmacology Unit, University of Patras Medical School, Rio Achaias, Greece
| | | | - Evangelia Zvintzou
- Department of Medicine, Pharmacology Unit, University of Patras Medical School, Rio Achaias, Greece
| | - Abdulmaged M Traish
- Departments of Urology and Biochemistry, Boston University School of Medicine, Boston, MA
| | - Peter J Voshol
- Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - Iordanes Karagiannides
- Department of Medicine, Pharmacology Unit, University of Patras Medical School, Rio Achaias, Greece
| | - Kyriakos E Kypreos
- Department of Medicine, Pharmacology Unit, University of Patras Medical School, Rio Achaias, Greece
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Li Y, Wong K, Giles A, Jiang J, Lee JW, Adams AC, Kharitonenkov A, Yang Q, Gao B, Guarente L, Zang M. Hepatic SIRT1 attenuates hepatic steatosis and controls energy balance in mice by inducing fibroblast growth factor 21. Gastroenterology 2014; 146:539-49.e7. [PMID: 24184811 PMCID: PMC4228483 DOI: 10.1053/j.gastro.2013.10.059] [Citation(s) in RCA: 219] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 09/22/2013] [Accepted: 10/24/2013] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS The hepatocyte-derived hormone fibroblast growth factor 21 (FGF21) is a hormone-like regulator of metabolism. The nicotinamide adenine dinucleotide-dependent deacetylase SIRT1 regulates fatty acid metabolism through multiple nutrient sensors. Hepatic overexpression of SIRT1 reduces steatosis and glucose intolerance in obese mice. We investigated mechanisms by which SIRT1 controls hepatic steatosis in mice. METHODS Liver-specific SIRT1 knockout (SIRT1 LKO) mice and their wild-type littermates (controls) were divided into groups that were placed on a normal chow diet, fasted for 24 hours, or fasted for 24 hours and then fed for 6 hours. Liver tissues were collected and analyzed by histologic examination, gene expression profiling, and real-time polymerase chain reaction assays. Human HepG2 cells were incubated with pharmacologic activators of SIRT1 (resveratrol or SRT1720) and mitochondrion oxidation consumption rate and immunoblot analyses were performed. FGF21 was overexpressed in SIRT1 LKO mice using an adenoviral vector. Energy expenditure was assessed by indirect calorimetry. RESULTS Prolonged fasting induced lipid deposition in livers of control mice, but severe hepatic steatosis in SIRT1 LKO mice. Gene expression analysis showed that fasting up-regulated FGF21 in livers of control mice but not in SIRT1 LKO mice. Decreased hepatic and circulating levels of FGF21 in fasted SIRT1 LKO mice were associated with reduced hepatic expression of genes involved in fatty acid oxidation and ketogenesis, and increased expression of genes that control lipogenesis, compared with fasted control mice. Resveratrol or SRT1720 each increased the transcriptional activity of the FGF21 promoter (-2070/+117) and levels of FGF21 messenger RNA and protein in HepG2 cells. Surprisingly, SIRT1 LKO mice developed late-onset obesity with impaired whole-body energy expenditure. Hepatic overexpression of FGF21 in SIRT1 LKO mice increased the expression of genes that regulate fatty acid oxidation, decreased fasting-induced steatosis, reduced obesity, increased energy expenditure, and promoted browning of white adipose tissue. CONCLUSIONS SIRT1-mediated activation of FGF21 prevents liver steatosis caused by fasting. This hepatocyte-derived endocrine signaling appears to regulate expression of genes that control a brown fat-like program in white adipose tissue, energy expenditure, and adiposity. Strategies to activate SIRT1 or FGF21 could be used to treat fatty liver disease and obesity.
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Affiliation(s)
- Yu Li
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts.
| | - Kimberly Wong
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Amber Giles
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Jianwei Jiang
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Jong Woo Lee
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Andrew C Adams
- Lilly Research Laboratories, Lilly Corporate Center, Indianapolis, Indiana
| | | | - Qin Yang
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts
| | - Bin Gao
- Laboratory of Liver Diseases, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland
| | - Leonard Guarente
- Department of Biology, Paul F. Glenn Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Mengwei Zang
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts.
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Nasarre L, Juan-Babot O, Gastelurrutia P, Llucia-Valldeperas A, Badimon L, Bayes-Genis A, Llorente-Cortés V. Low density lipoprotein receptor-related protein 1 is upregulated in epicardial fat from type 2 diabetes mellitus patients and correlates with glucose and triglyceride plasma levels. Acta Diabetol 2014; 51:23-30. [PMID: 23096408 DOI: 10.1007/s00592-012-0436-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 10/08/2012] [Indexed: 11/27/2022]
Abstract
Lipoprotein receptor expression plays a crucial role in the pathophysiology of adipose tissue in in vivo models of diabetes. However, there are no studies in diabetic patients. The aims of this study were to analyze (a) low-density lipoprotein receptor-related protein 1 (LRP1) and very low-density lipoprotein receptor (VLDLR) expression in epicardial and subcutaneous fat from type 2 diabetes mellitus compared with nondiabetic patients and (b) the possible correlation between the expression of these receptors and plasmatic parameters. Adipose tissue biopsy samples were obtained from diabetic (n = 54) and nondiabetic patients (n = 22) undergoing cardiac surgery before the initiation of cardiopulmonary bypass. Adipose LRP1 and VLDLR expression was analyzed at mRNA level by real-time PCR and at protein level by Western blot analysis. Adipose samples were also subjected to lipid extraction, and fat cholesterol ester, triglyceride, and free cholesterol contents were analyzed by thin-layer chromatography. LRP1 expression was higher in epicardial fat from diabetic compared with nondiabetic patients (mRNA 17.63 ± 11.37 versus 7.01 ± 4.86; P = 0.02; protein 11.23 ± 7.23 versus 6.75 ± 5.02, P = 0.04). VLDLR expression was also higher in epicardial fat from diabetic patients but only at mRNA level (231.25 ± 207.57 versus 56.64 ± 45.64, P = 0.02). No differences were found in the expression of LRP1 or VLDLR in the subcutaneous fat from diabetic compared with nondiabetic patients. Epicardial LRP1 and VLDLR mRNA overexpression positively correlated with plasma triglyceride levels (R(2) = 0.50, P = 0.01 and R(2) = 0.44, P = 0.03, respectively) and epicardial LRP1 also correlated with plasma glucose levels (R(2) = 0.33, P = 0.03). These results suggest that epicardial overexpression of certain lipoprotein receptors such as LRP1 and VLDLR expression may play a key role in the alterations of lipid metabolism associated with type 2 diabetes mellitus.
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Affiliation(s)
- L Nasarre
- Cardiovascular Research Center, CSIC-ICCC, IIB-Sant Pau, Hospital de la Santa Creu i Sant Pau, UAB, Sant Antoni Mª Claret, 167, 08025, Barcelona, Spain
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77
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Chatterjee TK, Basford JE, Knoll E, Tong WS, Blanco V, Blomkalns AL, Rudich S, Lentsch AB, Hui DY, Weintraub NL. HDAC9 knockout mice are protected from adipose tissue dysfunction and systemic metabolic disease during high-fat feeding. Diabetes 2014; 63:176-87. [PMID: 24101673 PMCID: PMC3868044 DOI: 10.2337/db13-1148] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 09/30/2013] [Indexed: 01/08/2023]
Abstract
During chronic caloric excess, adipose tissue expands primarily by enlargement of individual adipocytes, which become stressed with lipid overloading, thereby contributing to obesity-related disease. Although adipose tissue contains numerous preadipocytes, differentiation into functionally competent adipocytes is insufficient to accommodate the chronic caloric excess and prevent adipocyte overloading. We report for the first time that a chronic high-fat diet (HFD) impairs adipogenic differentiation, leading to accumulation of inefficiently differentiated adipocytes with blunted expression of adipogenic differentiation-specific genes. Preadipocytes from these mice likewise exhibit impaired adipogenic differentiation, and this phenotype persists during in vitro cell culture. HFD-induced impaired adipogenic differentiation is associated with elevated expression of histone deacetylase 9 (HDAC9), an endogenous negative regulator of adipogenic differentiation. Genetic ablation of HDAC9 improves adipogenic differentiation and systemic metabolic state during an HFD, resulting in diminished weight gain, improved glucose tolerance and insulin sensitivity, and reduced hepatosteatosis. Moreover, compared with wild-type mice, HDAC9 knockout mice exhibit upregulated expression of beige adipocyte marker genes, particularly during an HFD, in association with increased energy expenditure and adaptive thermogenesis. These results suggest that targeting HDAC9 may be an effective strategy for combating obesity-related metabolic disease.
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Affiliation(s)
- Tapan K. Chatterjee
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, OH
| | - Joshua E. Basford
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH
| | - Ellen Knoll
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, OH
| | - Wilson S. Tong
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, OH
| | - Victor Blanco
- Department of Emergency Medicine, University of Cincinnati, Cincinnati, OH
| | - Andra L. Blomkalns
- Department of Emergency Medicine, University of Cincinnati, Cincinnati, OH
| | - Steven Rudich
- Department of Surgery, University of Cincinnati, Cincinnati, OH
| | - Alex B. Lentsch
- Department of Surgery, University of Cincinnati, Cincinnati, OH
| | - David Y. Hui
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati, Cincinnati, OH
| | - Neal L. Weintraub
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati, Cincinnati, OH
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Frazier-Wood AC, Kabagambe EK, Wojczynski MK, Borecki IB, Tiwari HK, Smith CE, Ordovas JM, Arnett DK. The association between LRP-1 variants and chylomicron uptake after a high fat meal. Nutr Metab Cardiovasc Dis 2013; 23:1154-1158. [PMID: 23484911 PMCID: PMC3686991 DOI: 10.1016/j.numecd.2012.12.007] [Citation(s) in RCA: 7] [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: 08/01/2012] [Revised: 12/19/2012] [Accepted: 12/27/2012] [Indexed: 11/22/2022]
Abstract
BACKGROUND AND AIMS In vitro studies suggest that low density lipoprotein receptor-related protein 1 (LRP1) plays a role in the secondary uptake of chylomicrons. In addition, in vivo studies using LRP-1 knockout mice show these animals exhibit delayed chylomicron clearance. Whether this is true in humans is unknown. We aimed to determine whether genetic variants in LRP-1 are associated with postprandial chylomicron uptake in humans given an oral fat challenge. METHODS AND RESULTS As many as 817 men and women (mean age +/- standard deviation = 48.4 +/- 16.4 years) forming the study population for the Genetics of Lipid Lowering Drugs Network (GOLDN) study ingested an oral fat load of 700 kilocalories per m² of body surface area at 83% fat, after an 8-h fast. Chylomicrons were measured by nuclear resonance spectroscopy (NMR) at fasting, and 3.5 and 6 h after the meal. 26 Single nucleotide polymorphisms (SNPs) in the LRP-1 gene were genotyped on the Affymetrix 6.0 array. Chylomicrons were, as expected, zero at fasting. Mixed linear models adjusted for age, sex, study site and pedigree tested for associations between LRP-1 SNPs and changes in chylomicron concentrations 3.5-6 h. A gene-based test across all 26 SNPs was conducted which corrected for the linkage disequilibrium (LD) between SNPs. 11 LRP-1 SNPs were significantly associated with the change in chylomicron concentration correction for multiple testing (Q < 0.05). The subsequent gene-based test, was also significant (P = 0.01). CONCLUSION These results require replication but strongly indicate the role of LRP1 in postprandial lipoprotein uptake and/or clearance.
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Affiliation(s)
- A C Frazier-Wood
- Department of Epidemiology, University of Alabama at Birmingham, School of Public Health, Birmingham, AL 35294, United States; Division of Epidemiology, Human Genetics and Environmental Sciences, The University of Texas School of Public Health, Houston, TX 77030, United States.
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Inappropriate heat dissipation ignites brown fat thermogenesis in mice with a mutant thyroid hormone receptor α1. Proc Natl Acad Sci U S A 2013; 110:16241-6. [PMID: 24046370 DOI: 10.1073/pnas.1310300110] [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: 01/20/2023] Open
Abstract
Thyroid hormone is a major regulator of thermogenesis, acting both in peripheral organs and on central autonomic pathways. Mice heterozygous for a point mutation in thyroid hormone receptor α1 display increased thermogenesis as a consequence of high sympathetic brown fat stimulation. Surprisingly, despite the hypermetabolism, their body temperature is not elevated. Here we show, using isolated tail arteries, that defective thyroid hormone receptor α1 signaling impairs acetylcholine-mediated vascular relaxation as well as phenylephrine-induced vasoconstriction. Using infrared thermography on conscious animals, we demonstrate that these defects severely interfere with appropriate peripheral heat conservation and dissipation, which in turn leads to compensatory alterations in brown fat activity. Consequently, when the vasoconstrictive defect in mice heterozygous for a point mutation in thyroid hormone receptor α1 was reversed with the selective α1-adrenergic agonist midodrine, the inappropriate heat loss over their tail surface was reduced, normalizing brown fat activity and energy expenditure. Our analyses demonstrate that thyroid hormone plays a key role in vascular heat conservation and dissipation processes, adding a unique aspect to its well-documented functions in thermoregulation. The data thus facilitate understanding of temperature hypersensitivity in patients with thyroid disorders. Moreover, the previously unrecognized connection between cardiovascular regulation and metabolic activity revealed in this study challenges the interpretation of several experimental paradigms and questions some of the currently derived hypotheses on the role of thyroid hormone in thermogenesis.
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80
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Smith CE, Ngwa J, Tanaka T, Qi Q, Wojczynski MK, Lemaitre RN, Anderson JS, Manichaikul A, Mikkilä V, van Rooij FJA, Ye Z, Bandinelli S, Frazier-Wood AC, Houston DK, Hu F, Langenberg C, McKeown NM, Mozaffarian D, North KE, Viikari J, Zillikens MC, Djoussé L, Hofman A, Kähönen M, Kabagambe EK, Loos RJF, Saylor GB, Forouhi NG, Liu Y, Mukamal KJ, Chen YDI, Tsai MY, Uitterlinden AG, Raitakari O, van Duijn CM, Arnett DK, Borecki IB, Cupples LA, Ferrucci L, Kritchevsky SB, Lehtimäki T, Qi L, Rotter JI, Siscovick DS, Wareham NJ, Witteman JCM, Ordovás JM, Nettleton JA. Lipoprotein receptor-related protein 1 variants and dietary fatty acids: meta-analysis of European origin and African American studies. Int J Obes (Lond) 2013; 37:1211-20. [PMID: 23357958 PMCID: PMC3770755 DOI: 10.1038/ijo.2012.215] [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] [Received: 10/08/2012] [Revised: 11/15/2012] [Accepted: 11/28/2012] [Indexed: 01/23/2023]
Abstract
OBJECTIVE Low-density lipoprotein-related receptor protein 1 (LRP1) is a multi-functional endocytic receptor and signaling molecule that is expressed in adipose and the hypothalamus. Evidence for a role of LRP1 in adiposity is accumulating from animal and in vitro models, but data from human studies are limited. The study objectives were to evaluate (i) relationships between LRP1 genotype and anthropometric traits, and (ii) whether these relationships were modified by dietary fatty acids. DESIGN AND METHODS We conducted race/ethnic-specific meta-analyses using data from 14 studies of US and European whites and 4 of African Americans to evaluate associations of dietary fatty acids and LRP1 genotypes with body mass index (BMI), waist circumference and hip circumference, as well as interactions between dietary fatty acids and LRP1 genotypes. Seven single-nucleotide polymorphisms (SNPs) of LRP1 were evaluated in whites (N up to 42 000) and twelve SNPs in African Americans (N up to 5800). RESULTS After adjustment for age, sex and population substructure if relevant, for each one unit greater intake of percentage of energy from saturated fat (SFA), BMI was 0.104 kg m(-2) greater, waist was 0.305 cm larger and hip was 0.168 cm larger (all P<0.0001). Other fatty acids were not associated with outcomes. The association of SFA with outcomes varied by genotype at rs2306692 (genotyped in four studies of whites), where the magnitude of the association of SFA intake with each outcome was greater per additional copy of the T allele: 0.107 kg m(-2) greater for BMI (interaction P=0.0001), 0.267 cm for waist (interaction P=0.001) and 0.21 cm for hip (interaction P=0.001). No other significant interactions were observed. CONCLUSION Dietary SFA and LRP1 genotype may interactively influence anthropometric traits. Further exploration of this, and other diet x genotype interactions, may improve understanding of interindividual variability in the relationships of dietary factors with anthropometric traits.
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Affiliation(s)
- CE Smith
- Nutrition and Genomics Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
| | - J Ngwa
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
| | - T Tanaka
- Clinical Research Branch, National Institute on Aging, Baltimore, MD, USA
| | - Q Qi
- Department of Nutrition, Harvard School of Public Health, Boston, MA, USA
| | - MK Wojczynski
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - RN Lemaitre
- Department of Medicine, University of Washington, Seattle, WA, USA
| | - JS Anderson
- Department of Internal Medicine, Section on Cardiology, Wake Forest School of Medicine, Winston Salem, NC, USA
| | - A Manichaikul
- Center for Public Health Genomics and Division of Biostatistics and Epidemiology, University of Virginia, Charlottesville, VA, USA
| | - V Mikkilä
- Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - FJA van Rooij
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- The Netherlands Genomics Initiative–sponsored Netherlands Consortium for Healthy Aging (NGI-NCHA), Leiden, The Netherlands
| | - Z Ye
- MRC Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - S Bandinelli
- Geriatric Rehabilitation Unit, Azienda Sanitaria Firenze, Florence, Italy
| | - AC Frazier-Wood
- Department of Epidemiology, Section on Statistical Genetics, and The Office of Energetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - DK Houston
- Sticht Center on Aging, Wake Forest University School of Medicine, Winston Salem, NC, USA
| | - F Hu
- Department of Nutrition, Harvard School of Public Health, Boston, MA, USA
- Department of Medicine, Channing Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - C Langenberg
- MRC Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - NM McKeown
- Nutrition and Genomics Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
| | - D Mozaffarian
- Departments of Epidemiology and Nutrition, Harvard School of Public Health, Boston, MA, USA
- Division of Cardiovascular Medicine and Channing Laboratory, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - KE North
- Department of Epidemiology and Carolina Center for Genome Sciences; University of North Carolina; Chapel Hill, NC, USA
| | - J Viikari
- Department of Medicine, University of Turku and Turku University Hospital, Turku, Finland
| | - MC Zillikens
- The Netherlands Genomics Initiative–sponsored Netherlands Consortium for Healthy Aging (NGI-NCHA), Leiden, The Netherlands
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - L Djoussé
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, and Boston VA Healthcare System, Boston, MA, USA
| | - A Hofman
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- The Netherlands Genomics Initiative–sponsored Netherlands Consortium for Healthy Aging (NGI-NCHA), Leiden, The Netherlands
| | - M Kähönen
- Department of Clinical Physiology, University of Tampere and Tampere University Hospital, Tampere, Finland
| | - EK Kabagambe
- Department of Epidemiology, Section on Statistical Genetics, and The Office of Energetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - RJF Loos
- MRC Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - GB Saylor
- Department of Internal Medicine, Section on Cardiology, Wake Forest School of Medicine, Winston Salem, NC, USA
| | - NG Forouhi
- MRC Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - Y Liu
- Department of Epidemiology and Prevention, Division of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - KJ Mukamal
- Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Y-DI Chen
- Medical Genetics Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - MY Tsai
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USA
| | - AG Uitterlinden
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- The Netherlands Genomics Initiative–sponsored Netherlands Consortium for Healthy Aging (NGI-NCHA), Leiden, The Netherlands
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - O Raitakari
- Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku and the Department of Clinical Physiology and Nuclear Medicine, Turku University Hospital, Turku, Finland
| | - CM van Duijn
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- The Netherlands Genomics Initiative–sponsored Netherlands Consortium for Healthy Aging (NGI-NCHA), Leiden, The Netherlands
| | - DK Arnett
- Department of Epidemiology, Section on Statistical Genetics, and The Office of Energetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - IB Borecki
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - LA Cupples
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
- Framingham Heart Study, Framingham, MA, USA
| | - L Ferrucci
- Clinical Research Branch, National Institute on Aging, Baltimore, MD, USA
| | - SB Kritchevsky
- Sticht Center on Aging, Wake Forest University School of Medicine, Winston Salem, NC, USA
| | - T Lehtimäki
- Department of Clinical Chemistry, Fimlab Laboratories, University of Tampere and Tampere University Hospital, Tampere, Finland
| | - Lu Qi
- Department of Nutrition, Harvard School of Public Health, Boston, MA, USA
- Department of Medicine, Channing Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - JI Rotter
- Medical Genetics Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - DS Siscovick
- Departments of Medicine and Epidemiology, University of Washington, Seattle, WA, USA
| | - NJ Wareham
- MRC Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK
| | - JCM Witteman
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- The Netherlands Genomics Initiative–sponsored Netherlands Consortium for Healthy Aging (NGI-NCHA), Leiden, The Netherlands
| | - JM Ordovás
- Nutrition and Genomics Laboratory, Jean Mayer USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA
- Department of Epidemiology and Population Genetics, Centro Nacional Investigación Cardiovasculares (CNIC), Madrid, Spain
- Instituto Madrileños de Estudios Avanzados Alimentación, Madrid, Spain
| | - JA Nettleton
- Division of Epidemiology, Human Genetics and Environmental Sciences, University of Texas Health Science Center at Houston, Houston, TX, USA
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Smith CE, Tucker KL, Lee YC, Lai CQ, Parnell LD, Ordovás JM. Low-density lipoprotein receptor-related protein 1 variant interacts with saturated fatty acids in Puerto Ricans. Obesity (Silver Spring) 2013; 21:602-8. [PMID: 23404896 PMCID: PMC3630241 DOI: 10.1002/oby.20001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 05/31/2012] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Low-density lipoprotein receptor-related protein 1 (LRP1) is a multifunctional endocytic receptor that is highly expressed in adipocytes and the hypothalamus. Animal models and in vitro studies support a role for LRP1 in adipocyte metabolism and leptin signaling, but genetic polymorphisms have not been evaluated for obesity in people. DESIGN AND METHODS We examined whether dietary fats (eg., saturated, polyunsaturated) modulated the association of LRP1 rs1799986 with anthropometric traits. We studied a population-based sample of Puerto Ricans (n = 920, aged 45-74 y) living in the Boston area.We examined whether dietary fats (eg., saturated, polyunsaturated) modulated the association of LRP1 rs1799986 with anthropometric traits. We studied a population-based sample of Puerto Ricans (n = 920, aged 45-74 y) living in the Boston area. RESULTS In multivariable linear regression models, we dichotomized saturated fat intake and found significant interaction terms between total saturated fatty acids and LRP1 rs1799986 genotype for BMI (P=0.006) and hip (P = 0.002). High intake of saturated fat was associated with higher BMI (P = 0.001), waist (P = 0.008) and hip (P=0.003) in minor allele carriers (CT+TT) compared to CC participants. Further analysis of dichotomized individual saturated fatty acids revealed that interactions were strongest for two individual longer chain fatty acids. High intake of palmitic acid (C16:0; P = 0.0007) and high stearic acid intake (C18:0; P = 0.005) were associated with higher BMI in T carriers. Interactions were not detected for polyunsaturated fatty acids. CONCLUSIONS Gene-diet interactions at the LRP1 locus support the hypothesis that susceptibility to weight gain based on saturated fatty acids is modified by genotype and possibly by chain length. These results may facilitate the development of a panel of genetic candidates for use in optimizing dietary recommendations for obesity management.
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Affiliation(s)
- Caren E. Smith
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | | | - Yu-Chi Lee
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
- Tufts University School of Nutrition, Boston, MA, USA
| | - Chao-Qiang Lai
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | - Laurence D. Parnell
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | - José M. Ordovás
- Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
- Tufts University School of Nutrition, Boston, MA, USA
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Li Y, Wong K, Walsh K, Gao B, Zang M. Retinoic acid receptor β stimulates hepatic induction of fibroblast growth factor 21 to promote fatty acid oxidation and control whole-body energy homeostasis in mice. J Biol Chem 2013; 288:10490-504. [PMID: 23430257 DOI: 10.1074/jbc.m112.429852] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Activation of retinoic acid receptor (RAR) with all-trans-retinoic acid (RA) ameliorates glucose intolerance and insulin resistance in obese mice. The recently discovered fibroblast growth factor 21 (FGF21) is a hepatocyte-derived hormone that restores glucose and lipid homeostasis in obesity-induced diabetes. However, whether hepatic RAR is linked to FGF21 in the control of lipid metabolism and energy homeostasis remains elusive. Here we identify FGF21 as a direct target gene of RARβ. The gene transcription of Fgf21 is increased by the RAR agonist RA and by overexpression of RARα and RARβ, but it is unaffected by RARγ in HepG2 cells. Promoter deletion analysis characterizes a putative RA-responsive element (RARE) primarily located in the 5'-flanking region of the Fgf21 gene. Disruption of the RARE sequence abolishes RA responsiveness. In vivo adenoviral overexpression of RARβ in the liver enhances production and secretion of FGF21, which in turn promotes hepatic fatty acid oxidation and ketogenesis and ultimately leads to increased energy expenditure in mice. The metabolic effects of RA or RARβ are mimicked by FGF21 overexpression and largely abolished by FGF21 knockdown. Moreover, hepatic RARβ is bound to the putative RAREs of the Fgf21 promoter in a fasting-inducible manner in vivo, which contributes to FGF21 induction and the metabolic adaptation to prolonged fasting. In addition to other nuclear receptors, such as peroxisome proliferator-activated receptor α and retinoic acid receptor-related receptor α, RAR may act as a novel component to induce hepatic FGF21 in the regulation of lipid metabolism. The hepatic RAR-FGF21 pathway may represent a potential drug target for treating metabolic disorders.
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Affiliation(s)
- Yu Li
- Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
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Kuhel DG, Konaniah ES, Basford JE, McVey C, Goodin CT, Chatterjee TK, Weintraub NL, Hui DY. Apolipoprotein E2 accentuates postprandial inflammation and diet-induced obesity to promote hyperinsulinemia in mice. Diabetes 2013; 62:382-91. [PMID: 22961083 PMCID: PMC3554349 DOI: 10.2337/db12-0390] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Genetic studies have revealed the association between the ε2 allele of the apolipoprotein E (apoE) gene and greater risk of metabolic diseases. This study compared C57BL/6 mice in which the endogenous mouse gene has been replaced by the human APOE2 or APOE3 gene (APOE2 and APOE3 mice) to identify the mechanism underlying the relationship between ε2 and obesity and diabetes. In comparison with APOE3 mice, the APOE2 mice had elevated fasting plasma lipid and insulin levels and displayed prolonged postprandial hyperlipidemia accompanied by increased granulocyte number and inflammation 2 h after being fed a lipid-rich meal. In comparison with APOE3 mice, the APOE2 mice also showed increased adiposity when maintained on a Western-type, high-fat, high-cholesterol diet. Adipose tissue dysfunction with increased macrophage infiltration, abundant crown-like structures, and inflammation were also observed in adipose tissues of APOE2 mice. The severe adipocyte dysfunction and tissue inflammation corresponded with the robust hyperinsulinemia observed in APOE2 mice after being fed the Western-type diet. Taken together, these data showed that impaired plasma clearance of apoE2-containing, triglyceride-rich lipoproteins promotes lipid redistribution to neutrophils and adipocytes to accentuate inflammation and adiposity, thereby accelerating the development of hyperinsulinemia that will ultimately lead to advanced metabolic diseases.
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Affiliation(s)
- David G. Kuhel
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Eddy S. Konaniah
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Joshua E. Basford
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Courtney McVey
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Colleen T. Goodin
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Tapan K. Chatterjee
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - Neal L. Weintraub
- Department of Internal Medicine, Division of Cardiovascular Diseases, University of Cincinnati College of Medicine, Cincinnati, Ohio
| | - David Y. Hui
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio
- Corresponding author: David Y. Hui,
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84
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Novel function of bovine lactoferrin in lipid metabolism: Visceral fat reduction by enteric-coated lactoferrin. PHARMANUTRITION 2013. [DOI: 10.1016/j.phanu.2012.11.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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85
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Mullican SE, Tomaru T, Gaddis CA, Peed LC, Sundaram A, Lazar MA. A novel adipose-specific gene deletion model demonstrates potential pitfalls of existing methods. Mol Endocrinol 2012. [PMID: 23192980 DOI: 10.1210/me.2012-1267] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Adipose-specific gene deletion in mice is crucial in determining gene function in adipocyte homeostasis and the development of obesity. We noted 100% mortality when the Hdac3 gene was conditionally deleted using Fabp4-Cre mice, the most commonly used model of adipose-targeted Cre recombinase. However, this surprising result was not reproduced using other models of adipose targeting of Cre, including a novel Retn-Cre mouse. These findings underscore the need for caution when interpreting data obtained using Fabp4-Cre mice and should encourage the use of additional or alternative adipose-targeting Cre mouse models before drawing conclusions about in vivo adipocyte-specific functions.
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Affiliation(s)
- Shannon E Mullican
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, and The Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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Knock Down of Low Density Lipoprotein Receptor-related Protein 1(Lrp1) by RNAi Inhibits The Commitment of C3H10T1/2 Pluripotent Stem Cells to Preadipocyte*. PROG BIOCHEM BIOPHYS 2012. [DOI: 10.3724/sp.j.1206.2011.00594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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White HM, Acton AJ, Considine RV. The angiogenic inhibitor TNP-470 decreases caloric intake and weight gain in high-fat fed mice. Obesity (Silver Spring) 2012; 20:2003-9. [PMID: 22510957 PMCID: PMC3401363 DOI: 10.1038/oby.2012.87] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The angiogenic inhibitor TNP-470 attenuates high-fat diet-induced obesity; however, it is not clear how the compound alters energy balance to prevent weight gain. Five-week-old C57BL/6J mice were fed high-fat diet (45% energy from fat) for 6.5 weeks and treated with TNP-470 (20 mg/kg body weight; n = 7) or vehicle (saline; n = 7). Control mice (n = 8) received standard chow and sham injection. TNP-470 mice initially gained weight, but by day 5 body weight was significantly less than high-fat fed (HFF) mice and not different from that of chow-fed mice, an effect maintained to the end of the study (28.6 ± 0.6 vs. 22.4 ± 0.6 and 22.2 ± 0.5 g). Percent body fat was reduced in TNP-470 compared to HFF mice, but was greater than that of chow mice (34.0 ± 1.5, 23.9 ± 1.5, and 17.0 ± 1.4%, P < 0.05). Food intake in TNP-470-treated mice was less (P < 0.05) than that in HFF mice by day 5 of treatment (2.5 ± 0.1 vs. 2.8 ± 0.1 g/mouse/day) and remained so to the end of the study. Twenty-four hours energy expenditure was greater (P < 0.05) in TNP-470 than HFF or chow mice (7.05 ± 0.07 vs. 6.69 ± 0.08 vs. 6.79 ± 0.09 kcal/kg/h), an effect not explained by a difference in energy expended in locomotion. Despite normalization of body weight, TNP-470 mice exhibited impaired glucose tolerance (area under the curve 30,556 ± 1,918 and 29,290 ± 1,584 vs. 24,421 ± 903 for TNP, HFF, and chow fed, P < 0.05). In summary, the angiogenic inhibitor TNP-470 attenuates weight gain in HFF mice via a reduction in caloric intake and an increase in energy expenditure.
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Affiliation(s)
- Heather M White
- Division of Endocrinology, Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, USA
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88
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Wild J, Stather P, Sylvius N, Choke E, Sayers R, Bown M. Low Density Lipoprotein Receptor Related Protein 1 and Abdominal Aortic Aneurysms. Eur J Vasc Endovasc Surg 2012; 44:127-32. [DOI: 10.1016/j.ejvs.2012.05.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 05/08/2012] [Indexed: 12/15/2022]
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Cash JG, Kuhel DG, Basford JE, Jaeschke A, Chatterjee TK, Weintraub NL, Hui DY. Apolipoprotein E4 impairs macrophage efferocytosis and potentiates apoptosis by accelerating endoplasmic reticulum stress. J Biol Chem 2012; 287:27876-84. [PMID: 22730380 DOI: 10.1074/jbc.m112.377549] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Apolipoprotein (apo) E4 is a major genetic risk factor for a wide spectrum of inflammatory metabolic diseases, including atherosclerosis, diabetes, and Alzheimer disease. This study compared diet-induced adipose tissue inflammation as well as functional properties of macrophages isolated from human APOE3 and APOE4 mice to identify the mechanism responsible for the association between apoE4 and inflammatory metabolic diseases. The initial study confirmed previous reports that APOE4 gene replacement mice were less sensitive than APOE3 mice to diet-induced body weight gain but exhibited hyperinsulinemia, and their adipose tissues were similarly inflamed as those in APOE3 mice. Peritoneal macrophages isolated from APOE4 mice were defective in efferocytosis compared with APOE3 macrophages. Increased cell death was also observed in APOE4 macrophages when stimulated with LPS or oxidized LDL. Western blot analysis of cell lysates revealed that APOE4 macrophages displayed elevated JNK phosphorylation indicative of cell stress even under basal culturing conditions. Significantly higher cell stress due mainly to potentiation of endoplasmic reticulum (ER) stress signaling was also observed in APOE4 macrophages after LPS and oxidized LDL activation. The defect in efferocytosis and elevated apoptosis sensitivity of APOE4 macrophages was ameliorated by treatment with the ER chaperone tauroursodeoxycholic acid. Taken together, these results showed that apoE4 expression causes macrophage dysfunction and promotes apoptosis via ER stress induction. The reduction of ER stress in macrophages may be a viable option to reduce inflammation and inflammation-related metabolic disorders associated with the apoE4 polymorphism.
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Affiliation(s)
- James G Cash
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Institute, University of Cincinnati, Cincinnati, Ohio 45237, USA
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Yi CX, Al-Massadi O, Donelan E, Lehti M, Weber J, Ress C, Trivedi C, Müller TD, Woods SC, Hofmann SM. Exercise protects against high-fat diet-induced hypothalamic inflammation. Physiol Behav 2012; 106:485-90. [DOI: 10.1016/j.physbeh.2012.03.021] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Revised: 03/02/2012] [Accepted: 03/21/2012] [Indexed: 12/16/2022]
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Bielohuby M, Stemmer K, Berger J, Ramisch J, Smith K, Holland J, Parks K, Pfluger PT, Habegger KM, Tschöp MH, Seeley RJ, Bidlingmaier M. Carbohydrate content of post-operative diet influences the effect of vertical sleeve gastrectomy on body weight reduction in obese rats. Obes Surg 2012; 22:140-51. [PMID: 21971629 DOI: 10.1007/s11695-011-0528-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Vertical sleeve gastrectomy (VSG) effectively reduces body weight (BW) in obese rats and humans. However, post-surgical weight regain is frequently observed in subjects after VSG, but the underlying reasons remain poorly understood. We therefore investigated if post-surgical consumption of different diets can affect the outcome of VSG. METHODS VSG or sham operation was performed in Long-Evans rats with diet-induced obesity (n = 37). After post-surgical recovery, rats were fed ad libitum either with standard chow (CH), high-fat (HF) or low-carbohydrate, high-fat (LCHF) diets. BW and food intake were measured every second day; serum leptin, cholesterol, HDL cholesterol, and triglycerides were analyzed 4 weeks after surgery. Energy expenditure and locomotor activity were determined by a combined indirect calorimetry system, lean and fat mass by nuclear magnetic resonance. RESULTS After 4 weeks, BW gain, fat mass, and leptin were lower in VSG rats when compared to sham controls (p < 0.05). Energy expenditure and locomotor activity were not affected by VSG indicating that weight reduction derives from the significantly lower cumulative 4-week energy intake in VSG compared to sham. Sham rats fed LCHF consumed the most energy, followed by rats fed HF. In contrast, after VSG cumulative energy intake was highest in rats fed HF, but not different between CH and LCHF. Consistently, post-surgical BW and fat mass regain were highest in the HF-VSG group. Lipid profiles were improved by VSG but not differentially affected by diets. CONCLUSION In conclusion, consumption of a HF diet but not the more energy-dense LCHF diet reduced the effectiveness of VSG in rats.
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Affiliation(s)
- Maximilian Bielohuby
- Endocrine Research Unit, Medizinische Klinik Innenstadt, LMU, Ziemssenstr 1, 80336 Munich, Germany
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Abstract
To enhance glucose uptake into muscle and fat cells, insulin stimulates the translocation of GLUT4 glucose transporters from intracellular membranes to the cell surface. This response requires the intersection of insulin signaling and vesicle trafficking pathways, and it is compromised in the setting of overnutrition to cause insulin resistance. Insulin signals through AS160/Tbc1D4 and Tbc1D1 to modulate Rab GTPases and through the Rho GTPase TC10α to act on other targets. In unstimulated cells, GLUT4 is incorporated into specialized storage vesicles containing IRAP, LRP1, sortilin, and VAMP2, which are sequestered by TUG, Ubc9, and other proteins. Insulin mobilizes these vesicles directly to the plasma membrane, and it modulates the trafficking itinerary so that cargo recycles from endosomes during ongoing insulin exposure. Knowledge of how signaling and trafficking pathways are coordinated will be essential to understanding the pathogenesis of diabetes and the metabolic syndrome and may also inform a wide range of other physiologies.
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Affiliation(s)
- Jonathan S Bogan
- Section of Endocrinology and Metabolism, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520-8020, USA.
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93
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Novel aspects of the apolipoprotein-E receptor family: regulation and functional role of their proteolytic processing. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s11515-011-1186-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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94
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Molecular targets for 17α-ethynyl-5-androstene-3β,7β,17β-triol, an anti-inflammatory agent derived from the human metabolome. PLoS One 2012; 7:e32147. [PMID: 22384159 PMCID: PMC3286445 DOI: 10.1371/journal.pone.0032147] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 01/24/2012] [Indexed: 01/28/2023] Open
Abstract
HE3286, 17α-ethynyl-5-androstene-3β, 7β, 17β-triol, is a novel synthetic compound related to the endogenous sterol 5-androstene-3β, 7β, 17β-triol (β-AET), a metabolite of the abundant adrenal steroid dehydroepiandrosterone (DHEA). HE3286 has shown efficacy in clinical studies in impaired glucose tolerance and type 2 diabetes, and in vivo models of types 1 and 2 diabetes, autoimmunity, and inflammation. Proteomic analysis of solid-phase HE3286-bound bead affinity experiments, using extracts from RAW 264.7 mouse macrophage cells, identified 26 binding partners. Network analysis revealed associations of these HE3286 target proteins with nodes in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways for type 2 diabetes, insulin, adipokine, and adipocyte signaling. Binding partners included low density lipoprotein receptor-related protein (Lrp1), an endocytic receptor; mitogen activated protein kinases 1 and 3 (Mapk1, Mapk3), protein kinases involved in inflammation signaling pathways; ribosomal protein S6 kinase alpha-3 (Rsp6ka3), an intracellular regulatory protein; sirtuin-2 (Sirt2); and 17β-hydroxysteroid dehydrogenase 1 (Hsd17β4), a sterol metabolizing enzyme.
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95
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Preliminary evidence for an association between LRP-1 genotype and body mass index in humans. PLoS One 2012; 7:e30732. [PMID: 22347399 PMCID: PMC3275600 DOI: 10.1371/journal.pone.0030732] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Accepted: 12/26/2011] [Indexed: 12/02/2022] Open
Abstract
Background/Aims The LDL receptor-related protein-1 gene (LRP-1) has been associated with obesity in animal models, but no such association has yet been reported in humans. As data suggest this increase in fat mass may be mediated through a mechanism involving the clearance of plasma triglyceride-rich lipoproteins (TGRL), where the LRP interacts with apolipoprotein E (ApoE) on chylomicron remnants, we aimed to examine (1) whether there was an association between 3 single nucleotide polymorphisms (SNPs) on LRP-1 with body mass index (BMI) and (2) whether any association between LRP-1 SNPs and BMI could be modified by polymorphisms on the ApoE gene when comparing the wild type ε3/ε3 genotype against mutant ApoE allele (ε2/ε4) carriers. Methods/Results We used data from 1,036 men and women (mean age±SD = 49±16 y) participating in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) Study. Mixed linear models, which controlled for age, sex, alcohol intake and smoking, as well as family pedigree and center of data collection were calculated. Models that used LRP-1 genotype as a predictor of BMI revealed that individuals who were homozygous for the minor allele at the LRP-1 I10701 locus had BMIs, on average, 1.03 kg/m2 higher than major allele carriers (P = 0.03). In subsequent mixed linear models that included main effects of LRP-1 I10701 SNP and ApoE alleles, and an interaction term the two genotypes, there was no interaction detected between the LRP-1 I70701 genotype with either the ApoE ε2 or ε4 allele carriers (P>0.05). Conclusions This has implications for starting to understand pathways from genotype to human BMI, which may operate through TGRL uptake at the LRP-1 receptor. This may pave the way for future research into individualized dietary interventions.
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96
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Cam A, de Mejia EG. Role of dietary proteins and peptides in cardiovascular disease. Mol Nutr Food Res 2011; 56:53-66. [PMID: 22121103 DOI: 10.1002/mnfr.201100535] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 09/28/2011] [Accepted: 10/11/2011] [Indexed: 01/08/2023]
Abstract
Cardiovascular disease (CVD) is the leading cause of death for both men and women in the United States and most other countries. Therefore, a disease of such wide-ranging impact calls for the development of multiple viable strategies for prevention. Diet plays an important role in the development of the major risk factors of CVD such as low-grade systemic inflammation, hypertension, obesity, diabetes and atherosclerosis, the most significant. Thus, diet-based methods of prevention would not only be more feasible, but ultimately more cost-effective than relying on drugs to combat this condition. In recent years, peptides derived from either animal or plant sources have been found to have various bioactive properties. Nevertheless, their potential impact on inflammation and prevention of atherosclerosis has not been fully explored, particularly at the molecular level. In this review, the most current scientific information from in vitro, in vivo and clinical studies on the role of dietary proteins and peptides on CVD has been summarized and discussed.
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Affiliation(s)
- Anthony Cam
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, IL 61801, USA
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97
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Catasus L, Gallardo A, Llorente-Cortes V, Escuin D, Muñoz J, Tibau A, Peiro G, Barnadas A, Lerma E. Low-density lipoprotein receptor–related protein 1 is associated with proliferation and invasiveness in Her-2/neu and triple-negative breast carcinomas. Hum Pathol 2011; 42:1581-8. [DOI: 10.1016/j.humpath.2011.01.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Revised: 01/19/2011] [Accepted: 01/22/2011] [Indexed: 12/18/2022]
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Dominiczak MH, Caslake MJ. Apolipoproteins: metabolic role and clinical biochemistry applications. Ann Clin Biochem 2011; 48:498-515. [PMID: 22028427 DOI: 10.1258/acb.2011.011111] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Lipoprotein metabolism is dependent on apolipoproteins, multifunctional proteins that serve as templates for the assembly of lipoprotein particles, maintain their structure and direct their metabolism through binding to membrane receptors and regulation of enzyme activity. The three principal functions of lipoproteins are contribution to interorgan fuel (triglyceride) distribution (by means of the fuel transport pathway), to the maintenance of the extracellular cholesterol pool (by means of the overflow pathway) and reverse cholesterol transport. The most important clinical application of apolipoprotein measurements in the plasma is in the assessment of cardiovascular risk. Concentrations of apolipoprotein B and apolipoprotein AI (and their ratio) seem to be better markers of cardiovascular risk than conventional markers such as total cholesterol and LDL-cholesterol. Apolipoprotein measurements are also better standardized than the conventional tests. We suggest that measurements of apolipoprotein AI and apolipoprotein B are included as a part of the specialist lipid profile. We also suggest that lipoprotein (a) should be measured as part of the initial assessment of dyslipidaemias because of its consistent association with cardiovascular risk. Genotyping of apolipoprotein E isoforms remains useful in the investigation of mixed dyslipidaemias. Lastly, the role of postprandial metabolism is increasingly recognized in the context of atherogenesis, obesity and diabetes. This requires better markers of chylomicrons, very-low-density lipoproteins and remnant particles. Measurements of apolipoprotein B48 and remnant lipoprotein cholesterol are currently the key tests in this emerging field.
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Affiliation(s)
- Marek H Dominiczak
- NHS Greater Glasgow and Clyde Clinical Biochemistry Service and College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 0YN, UK.
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Llorente-Cortes V, Casani L, Cal R, Llenas A, Juan-Babot O, Camino-López S, Sendra J, Badimon L. Cholesterol-lowering strategies reduce vascular LRP1 overexpression induced by hypercholesterolaemia. Eur J Clin Invest 2011; 41:1087-97. [PMID: 21434892 DOI: 10.1111/j.1365-2362.2011.02513.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Low density lipoprotein receptor-related protein (LRP1) plays a key role on vascular functionality and is upregulated by hypercholesterolemia and hypertension. To investigate the effect of cholesterol-lowering interventions on vascular LRP1 over expression and whether simvastatin influences LRP1 expression. MATERIAL AND METHODS Male New Zealand rabbits were recruited into various groups, one group was fed a normal chow diet for 28 days (control group, n = 6), other group (n = 24) was fed a hypercholesterolemic diet (HC), six rabbits were euthanized at day 28 to test the capacity of HC diet to induce early atherosclerosis and the rest at day 60 (n = 18) after receiving either HC diet (HC group, n = 6), HC diet with simvastatin (2·5 mg/kg.day) (HC+simv group, n = 6), or a normal chow diet (NC group, n = 6) for the last 32 days. RESULTS High-cholesterol diet raised vascular LRP1 concomitantly with increased lipid, VSMC and macrophage content in the arterial intima. Simvastatin and return to normocholesterolemic diet significantly reduced systemic cholesterol levels and vascular lipid content. Interestingly, these interventions also downregulate LRP1 overexpression in the vascular wall although to a different extent (HC+simv: 75 ± 3·6%vs NC: 50 ± 3·5% versus, P = 0·002). Immunohistochemistry studies showed that LRP1 diminushion was associated to a reduction in the number of intimal VSMC in HC+simv.group. Simvastatin per se did not exert any significant effect on LRP1 expression in rabbit aortic smooth muscle cells (rSMC). CONCLUSIONS Our results demonstrate that cholesterol-lowering interventions exerted down regulatory effects on vascular LRP1 over expression induced by hypercholesterolemia and that simvastatin did not influence LRP1 expression beyond its cholesterol-lowering effects.
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Affiliation(s)
- Vicenta Llorente-Cortes
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau-UAB, Barcelona, Spain
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100
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Clemente-Postigo M, Queipo-Ortuño MI, Fernandez-Garcia D, Gomez-Huelgas R, Tinahones FJ, Cardona F. Adipose tissue gene expression of factors related to lipid processing in obesity. PLoS One 2011; 6:e24783. [PMID: 21966368 PMCID: PMC3178563 DOI: 10.1371/journal.pone.0024783] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 08/17/2011] [Indexed: 12/03/2022] Open
Abstract
Background Adipose tissue lipid storage and processing capacity can be a key factor for obesity-related metabolic disorders such as insulin resistance and diabetes. Lipid uptake is the first step to adipose tissue lipid storage. The aim of this study was to analyze the gene expression of factors involved in lipid uptake and processing in subcutaneous (SAT) and visceral (VAT) adipose tissue according to body mass index (BMI) and the degree of insulin resistance (IR). Methods and Principal Findings VLDL receptor (VLDLR), lipoprotein lipase (LPL), acylation stimulating protein (ASP), LDL receptor-related protein 1 (LRP1) and fatty acid binding protein 4 (FABP4) gene expression was measured in VAT and SAT from 28 morbidly obese patients with Type 2 Diabetes Mellitus (T2DM) or high IR, 10 morbidly obese patients with low IR, 10 obese patients with low IR and 12 lean healthy controls. LPL, FABP4, LRP1 and ASP expression in VAT was higher in lean controls. In SAT, LPL and FABP4 expression were also higher in lean controls. BMI, plasma insulin levels and HOMA-IR correlated negatively with LPL expression in both VAT and SAT as well as with FABP4 expression in VAT. FABP4 gene expression in SAT correlated inversely with BMI and HOMA-IR. However, multiple regression analysis showed that BMI was the main variable contributing to LPL and FABP4 gene expression in both VAT and SAT. Conclusions Morbidly obese patients have a lower gene expression of factors related with lipid uptake and processing in comparison with healthy lean persons.
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Affiliation(s)
- Mercedes Clemente-Postigo
- Laboratorio de Investigaciones Biomédicas del Hospital Virgen de la Victoria, Málaga (Fundación IMABIS), Spain
| | - Maria Isabel Queipo-Ortuño
- Laboratorio de Investigaciones Biomédicas del Hospital Virgen de la Victoria, Málaga (Fundación IMABIS), Spain
- CIBER Fisiopatología de la Obesidad y la Nutrición, Spain
| | - Diego Fernandez-Garcia
- CIBER Fisiopatología de la Obesidad y la Nutrición, Spain
- Servicio Endocrinología y Nutrición del Hospital Universitario Virgen de la Victoria, Málaga, Spain
| | - Ricardo Gomez-Huelgas
- CIBER Fisiopatología de la Obesidad y la Nutrición, Spain
- Servicio de Medicina Interna del Hospital Regional Carlos Haya, Spain
| | - Francisco J. Tinahones
- CIBER Fisiopatología de la Obesidad y la Nutrición, Spain
- Servicio Endocrinología y Nutrición del Hospital Universitario Virgen de la Victoria, Málaga, Spain
| | - Fernando Cardona
- Laboratorio de Investigaciones Biomédicas del Hospital Virgen de la Victoria, Málaga (Fundación IMABIS), Spain
- CIBER Fisiopatología de la Obesidad y la Nutrición, Spain
- * E-mail:
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