1 ADIPOCYTE ATP-BINDING CASSETTE G1 PROMOTES TRIGLYCERIDE STORAGE, FAT MASS GROWTH AND HUMAN OBESITY Eric FRISDAL 1,2,3 , Soazig LE LAY 4 , Henri HOOTON 2,6 , Lucie POUPEL 3 , Maryline OLIVIER 1,2 , Rohia ALILI 2,3,6 , Wanee PLENGPANICH 1,8 , Elise F. VILLARD 1,2,3 , Sophie GILIBERT 1,2,3 , Marie LHOMME 3 , Alexandre SUPERVILLE 1,2,3 , Lobna MIFTAH-ALKHAIR 1 , M. John CHAPMAN 1,2 , Geesje M. DALLINGA- THIE 5 , Nicolas VENTECLEF 2,3,6 , Christine POITOU 2,3,6,7 , Joan TORDJMAN 2,3,6 , Philippe LESNIK 1,2,3 , Anatol KONTUSH 1,2,3 , Thierry HUBY 1,2,3 , Isabelle DUGAIL 2,3,6 , Karine CLEMENT 2,3,6,7 , Maryse GUERIN 1,2,3 and Wilfried LE GOFF 1,2,3 1- INSERM, UMR_S1166, Team 4, F-75013 Paris, France; 2- Université Pierre et Marie Curie-Paris6, F-75005 Paris, France; 3- Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière hospital, F-75013 Paris, France; 4- INSERM, U1063, F-49933 Angers, France; 5- AMC Amsterdam, Laboratory of Vascular Medicine, Amsterdam, The Netherlands; 6- INSERM, U872, Nutriomique team 7, Cordeliers Research Center, F-75006, Paris, France; 7- Assistance-Publique Hôpitaux de Paris, Heart and Metabolism, Pitié-Salpêtrière hospital, F-75013, Paris, France; 8- King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Patumwan, Bangkok 10330, Thailand. Word count: 6610 Key Words: ABCG1, LPL, PPARγ, RNAi, adipocyte, obesity *Address correspondence to: Wilfried LE GOFF, PhD. INSERM UMR_S1166 Team 4 : Integrative Biology of Atherosclerosis Hôpital de la Pitié Pavillon Benjamin Delessert 83, boulevard de l’Hôpital 75651 Paris Cedex 13 France Tel: +33 1 42 17 79 77 Fax: +33 1 45 82 81 98 email: [email protected]Page 1 of 46 Diabetes , * Diabetes Publish Ahead of Print, published online September 23, 2014
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ADIPOCYTE ATP-BINDING CASSETTE G1 PROMOTES TRIGLYCERIDE STORAGE, FAT MASS
GROWTH AND HUMAN OBESITY
Eric FRISDAL1,2,3
, Soazig LE LAY4, Henri HOOTON
2,6, Lucie POUPEL
3, Maryline OLIVIER
1,2, Rohia
ALILI2,3,6
, Wanee PLENGPANICH1,8
, Elise F. VILLARD1,2,3
, Sophie GILIBERT1,2,3
, Marie LHOMME3,
Alexandre SUPERVILLE1,2,3
, Lobna MIFTAH-ALKHAIR1, M. John CHAPMAN
1,2, Geesje M. DALLINGA-
THIE5, Nicolas VENTECLEF
2,3,6, Christine POITOU
2,3,6,7, Joan TORDJMAN
2,3,6, Philippe LESNIK
1,2,3, Anatol
KONTUSH1,2,3
, Thierry HUBY1,2,3
, Isabelle DUGAIL2,3,6
, Karine CLEMENT 2,3,6,7
, Maryse GUERIN1,2,3
and
Wilfried LE GOFF1,2,3
1- INSERM, UMR_S1166, Team 4, F-75013 Paris, France;
2- Université Pierre et Marie Curie-Paris6, F-75005 Paris, France;
3- Institute of Cardiometabolism and Nutrition (ICAN), Pitié-Salpêtrière hospital, F-75013 Paris, France;
4- INSERM, U1063, F-49933 Angers, France;
5- AMC Amsterdam, Laboratory of Vascular Medicine, Amsterdam, The Netherlands;
6- INSERM, U872, Nutriomique team 7, Cordeliers Research Center, F-75006, Paris, France;
7- Assistance-Publique Hôpitaux de Paris, Heart and Metabolism, Pitié-Salpêtrière hospital, F-75013, Paris,
France;
8- King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Patumwan, Bangkok 10330, Thailand.
*Address correspondence to: Wilfried LE GOFF, PhD. INSERM UMR_S1166 Team 4 : Integrative Biology of Atherosclerosis Hôpital de la Pitié Pavillon Benjamin Delessert 83, boulevard de l’Hôpital 75651 Paris Cedex 13 France Tel: +33 1 42 17 79 77 Fax: +33 1 45 82 81 98 email: [email protected]
Page 1 of 46 Diabetes
,*
Diabetes Publish Ahead of Print, published online September 23, 2014
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Abstract.
The role of ATP-binding Cassette G1 (ABCG1) transporter in human pathophysiology is still
largely unknown. Indeed, beyond its role in mediating free cholesterol efflux to HDL, ABCG1
transporter equally promotes lipid accumulation in a triglyceride (TG)-rich environment through
regulation of the bioavailability of Lipoprotein Lipase (LPL).
As both ABCG1 and LPL are expressed in adipose tissue, we hypothesize that ABCG1 is
implicated in adipocyte TG storage and could be then a major actor in adipose tissue fat accumulation.
Silencing of Abcg1 expression by RNAi in 3T3-L1 preadipocytes compromised LPL-dependent
TG accumulation during initial phase of differentiation. Generation of stable Abcg1 Knockdown 3T3-L1
adipocytes revealed that Abcg1 deficiency reduces TG storage and diminishes lipid droplet size
through inhibition of Pparγ expression. Strikingly, local inhibition of adipocyte Abcg1 in adipose tissue
from mice fed a high fat diet led to a rapid decrease of adiposity and weight gain. Analysis of two
frequent ABCG1 SNPs (rs1893590 (A/C) and rs1378577 (T/G)) in morbidly obese individuals indicated
that elevated ABCG1 expression in adipose tissue was associated with an increased PPARγ
expression and adiposity concomitant to an increased fat mass and BMI (haplotype AT>GC). The
critical role of ABCG1 regarding obesity was further confirmed in independent populations of severe
obese and diabetic obese individuals.
For the first time, this study identifies a major role of adipocyte ABCG1 in adiposity and fat
mass growth and suggests that adipose ABCG1 might represent a potential therapeutic target in
obesity.
Page 2 of 46Diabetes
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Introduction.
The ATP-binding cassette G1 (ABCG1) transporter has been proposed to promote cellular
cholesterol efflux to HDL (1) and targeted disruption of Abcg1 was shown to induce massive tissue
neutral lipid accumulation in mice fed a high-fat/high-cholesterol diet (2). However the precise role of
ABCG1 is still matter of debate, especially in human pathophysiology (3).
We recently reported that two frequent ABCG1 SNPs (rs1893590 and rs1378577) were
significantly associated to plasma lipoprotein lipase (LPL) activity in the Regression Growth Evaluation
Statin Study (REGRESS) population (4). Analysis of the relationship between ABCG1 genotype and
LPL led us to propose a mechanism by which ABCG1 controls macrophage LPL activity through
modulation of membrane lipid rafts to promote intracellular lipid accumulation and foam cell formation
in a triglyceride (TG)-rich context (4). Thus, beyond a role in sterol export to HDL, ABCG1 may equally
contribute to intracellular fatty acid accumulation and lipid storage in metabolic situations associated
with elevated levels of circulating TG-rich lipoproteins. Consistent with a role of Abcg1 in lipid storage,
random insertion of modified transposable elements of the P-family in Drosophila melanogaster
identified the CG17646 locus, the Drosophila ortholog of Abcg1, as a candidate gene for TG storage
(5). Moreover, total ablation of Abcg1 in mice fed a high fat diet devoid of cholesterol (5) reduced TG
accumulation in the adipose and liver tissues. However the cellular mechanisms underlying this
phenotype, and more specifically the tissue-specific contribution of Abcg1, were not elucidated.
Considered together, these data prompted us to evaluate the function of ABCG1in adipocytes which
are professional cells for TG storage.
ATP-Binding Cassette G1 is expressed in adipocytes and in adipose tissue of mice, which
develop diet-induced obesity (5; 6). Moreover, adipose tissue is a major source of LPL (7) which
critically controls TG accumulation by generating free fatty acids from circulating lipoproteins (8).
Our data demonstrate that silencing of Abcg1 expression in adipocyte reduced LPL activity
and alters lipid homeostasis. Moreover, Abcg1 deficiency resulted in inhibition of Pparγ expression
and alteration of adipocyte maturation. In vivo, local lentiviral-mediated adipose tissue targeting of
Abcg1 rapidly reduced adiposity and high-fat diet-induced weight gain in mice. More strikingly, we
observed that ABCG1 genotype in humans was associated to fat mass formation and obesity in
independent populations of obese individuals, thereby highlighting the critical role of ABCG1 in the
Page 3 of 46 Diabetes
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context of human obesity. Taken together, the present study suggests that adipose tissue ABCG1
might represent a future therapeutic target in metabolic disorders associated to obesity.
J.T., I.D., P.L., A.K., T.H., M.G. and W.L.G. contributed to the experimental work and/or data analysis.
E.F., S.L.L., I.D., T.H., K.C., M.G. and W.L.G. contributed to the development of the study. KC and CP
contributed to patients’ recruitment and phenotyping and biobank constitution. All authors contributed
to the development of the manuscript. W.L.G. wrote the manuscript, conceived, designed and
supervised the study.
Acknowledgements
INSERM and UPMC (Parinov program) provided generous support of these studies. M.O., E.F.V. and
A.S. were recipient of a Research Fellowship from the French Ministry of Research and Technology.
W.L.G. was the recipient of a PNRC award from INSERM. W.P. was the recipient of a junior research
fellowship from the French Embassy in Thailand. The INSERM U872 team thanks Assistance
publique/hôpitaux de Paris, Programme Hospitalier de recherche clinique (PHRC 1996 and 2002) for
supporting the genetic DNA bank on obesity. The ethic committee (Comité Protection des personnes
N° 1 Hôtel-Dieu) provided the ethic agreements. This work was supported by the Fondation de France
(W.L.G., P.L. and T.H.) and by the French National Agency through the national program
“Investissements d’avenir” with the reference ANR-10-IAHU-05. The authors are indebted to the
patients for their cooperation. Dr. Wilfried Le Goff is the guarantor of this work and, as such, had full
access to all the data in the study and takes responsibility for the integrity of the data and the accuracy
of the data analysis.
Disclosures
None
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produces a novel transcript encoding an alternative form of the protein. The Journal of biological chemistry 2001;276:39438-39447 31. Out R, Hoekstra M, Meurs I, de Vos P, Kuiper J, Van Eck M, Van Berkel TJ: Total body ABCG1 expression protects against early atherosclerotic lesion development in mice. Arterioscler Thromb Vasc Biol 2007;27:594-599 32. Baldan A, Tarr P, Vales CS, Frank J, Shimotake TK, Hawgood S, Edwards PA: Deletion of the transmembrane transporter ABCG1 results in progressive pulmonary lipidosis. The Journal of biological chemistry 2006;281:29401-29410 33. Burgess B, Naus K, Chan J, Hirsch-Reinshagen V, Tansley G, Matzke L, Chan B, Wilkinson A, Fan J, Donkin J, Balik D, Tanaka T, Ou G, Dyer R, Innis S, McManus B, Lutjohann D, Wellington C: Overexpression of human ABCG1 does not affect atherosclerosis in fat-fed ApoE-deficient mice. Arterioscler Thromb Vasc Biol 2008;28:1731-1737 34. Ntambi JM, Young-Cheul K: Adipocyte differentiation and gene expression. The Journal of nutrition 2000;130:3122S-3126S 35. Babaev VR, Fazio S, Gleaves LA, Carter KJ, Semenkovich CF, Linton MF: Macrophage lipoprotein lipase promotes foam cell formation and atherosclerosis in vivo. J Clin Invest 1999;103:1697-1705 36. Wang H, Eckel RH: Lipoprotein lipase: from gene to obesity. Am J Physiol Endocrinol Metab 2009;297:E271-288 37. Radha V, Vimaleswaran KS, Ayyappa KA, Mohan V: Association of lipoprotein lipase gene polymorphisms with obesity and type 2 diabetes in an Asian Indian population. Int J Obes (Lond) 2007;31:913-918 38. Jemaa R, Tuzet S, Portos C, Betoulle D, Apfelbaum M, Fumeron F: Lipoprotein lipase gene polymorphisms: associations with hypertriglyceridemia and body mass index in obese people. Int J Obes Relat Metab Disord 1995;19:270-274 39. Weinstock PH, Levak-Frank S, Hudgins LC, Radner H, Friedman JM, Zechner R, Breslow JL: Lipoprotein lipase controls fatty acid entry into adipose tissue, but fat mass is preserved by endogenous synthesis in mice deficient in adipose tissue lipoprotein lipase. Proc Natl Acad Sci U S A 1997;94:10261-10266 40. Lehmann JM, Moore LB, Smith-Oliver TA, Wilkison WO, Willson TM, Kliewer SA: An antidiabetic thiazolidinedione is a high affinity ligand for peroxisome proliferator-activated receptor gamma (PPAR gamma). The Journal of biological chemistry 1995;270:12953-12956 41. Schoonjans K, Peinado-Onsurbe J, Lefebvre AM, Heyman RA, Briggs M, Deeb S, Staels B, Auwerx J: PPARalpha and PPARgamma activators direct a distinct tissue-specific transcriptional response via a PPRE in the lipoprotein lipase gene. The EMBO journal 1996;15:5336-5348 42. Bouaboula M, Hilairet S, Marchand J, Fajas L, Le Fur G, Casellas P: Anandamide induced PPARgamma transcriptional activation and 3T3-L1 preadipocyte differentiation. European journal of pharmacology 2005;517:174-181 43. Seo JB, Moon HM, Kim WS, Lee YS, Jeong HW, Yoo EJ, Ham J, Kang H, Park MG, Steffensen KR, Stulnig TM, Gustafsson JA, Park SD, Kim JB: Activated liver X receptors stimulate adipocyte differentiation through induction of peroxisome proliferator-activated receptor gamma expression. Molecular and cellular biology 2004;24:3430-3444 44. Tamori Y, Masugi J, Nishino N, Kasuga M: Role of peroxisome proliferator-activated receptor-gamma in maintenance of the characteristics of mature 3T3-L1 adipocytes. Diabetes 2002;51:2045-2055
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45. Jones JR, Barrick C, Kim KA, Lindner J, Blondeau B, Fujimoto Y, Shiota M, Kesterson RA, Kahn BB, Magnuson MA: Deletion of PPARgamma in adipose tissues of mice protects against high fat diet-induced obesity and insulin resistance. Proc Natl Acad Sci U S A 2005;102:6207-6212 46. He W, Barak Y, Hevener A, Olson P, Liao D, Le J, Nelson M, Ong E, Olefsky JM, Evans RM: Adipose-specific peroxisome proliferator-activated receptor gamma knockout causes insulin resistance in fat and liver but not in muscle. Proc Natl Acad Sci U S A 2003;100:15712-15717 47. Takahashi M, Yagyu H, Tazoe F, Nagashima S, Ohshiro T, Okada K, Osuga J, Goldberg IJ, Ishibashi S: Macrophage lipoprotein lipase modulates the development of atherosclerosis but not adiposity. J Lipid Res 2013;54:1124-1134
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Figure Legends.
Figure 1. Abcg1-silencing in preadipocytes affects TG storage in a LPL-dependent manner. A.
Levels of Abcg1 mRNA and (B) correlation between Abcg1 mRNA and cellular TG storage during
adipocyte differentiation (from D0 to D13). The efficiency of the Abcg1 knockdown in 3T3-L1
adipocytes was assessed by quantification of mRNA (C) and protein (D) levels. E. Evaluation of Lpl
mRNA levels (F), secreted LPL activity and (G) membrane lipid raft formation in Ctrl and Abcg1
Knockdown (KD) 3T3-L1 adipocyte. Representative photographs of lipid rafts visualized by
fluorescence microscopy (x63). Cellular triglyceride content was quantified (H) during maturation (from
D0 to D4) of Ctrl and Abcg1 KD 3T3-L1 preadipocytes into adipocytes. I. Impact of a 24h-treatment
with either tetrahydrolipstatin (THL) or increasing doses of bovine LPL (bLPL) on cellular triglycerides
mass and secreted LPL activity during control adipocyte differentiation (D6). Data are shown as mean
± SEM. Experiments were performed in triplicate. *p<0.05 and **p<0.005 versus control cells.
Figure 2. Gene expression profile in stable Abcg1 Kd 3T3-L1 mature adipocyte. Quantification of
protein (A) and mRNA levels (B-J) levels in different stable 3T3-L1 adipocytes generated following the
infection with lentiviral (L) or retroviral (R) particles expressing control shRNA (L-Ctrl and R-Ctrl,
respectively) or shRNAs targeting the cDNA sequence of mouse Abcg1 gene (L1, L2, L3 and R1, R2,
respectively) following 10 days of differentiation. A similar gene expression pattern was observed in all
the Abcg1 KD adipocytes generated. Decreased expression of Pparγ and Pparγ-target genes in stable
Abcg1 KD adipocytes clones compared to stable control adipocytes. Data are shown as mean ± SEM.
Experiments were performed in triplicate. *p<0.05, **p<0.005 and ***p<0.005 versus respective control
cells.
Figure 3. Stable Abcg1 Knockdown compromises 3T3-L1 adipocyte lipid storage. A. Total
protein levels were assessed by Western blots analysis. Quantification of Abcg1, Pparγ, Perilipin and
Fabp4 protein levels in stable control (Ctrl) and Abcg1 SKD 3T3-L1 adipocytes following 10 days of
differentiation. F. Phase-contrast photographs representative of lipid droplets in control (Ctrl) and
Abcg1 SKD 3T3-L1 adipocytes visualized by microscopy (x20). G. Measurement of lipid droplets size
and quantification of cellular (H) triglycerides and (K) free cholesterol masses in stable control (Ctrl)
and Abcg1 SKD 3T3-L1 adipocytes following 10 days of differentiation. I. Rescue of impaired TG
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storage in Abcg1 SKD adipocytes upon incubation with exogenous bovine LPL (bLPL) for the last 24h
(Days: 1) or all along the 10 days of the maturation period (Days: 10). J. Cellular [3H]Cholesterol efflux
to apoAI or HDL from mature control (Ctrl) and Abcg1 SKD adipocytes (D10). Data are shown as
mean ± SEM. Experiments were performed in triplicate. *p<0.05 and **p<0.005 versus control cells.
Figure 4. Increased sphyingomyelin content in Abcg1 knockdown adipocytes is associated
with an altered LPL-dependent TG storage. Sphingomyelin (SM) efflux to BSA (A) and intracellular
SM mass (B) in mature control (Ctrl) and Abcg1 SKD adipocytes (D10). Secreted LPL activity (C) and
intracellular TG mass (D) in adipocytes (D10) enriched or depleted with either SM or
sphingomyelinase (SMase) for 16 hours, respectively.
Figure 5. Knockdown of adipose tissue Abcg1 following shRNA lentiviral local delivery. A.
Scheme of the experimental procedure. B. Abcg1 expression in epididymal adipose tissue from a
C57BL/6 mouse was visualized by fluorescence microscopy (x63). Arrows indicate Abcg1 expression
(green) in adipocytes (red, perilipin). Nuclei were counterstained with DAPI (blue). Recovery of GFP
fluorescence in adipose tissue from an individual C57BL/6 mouse fed a high fat diet (60% fat) 4 weeks
following the local injection in the epididymal adipose tissue of lentiviral particles encoding either a
shRNA control (C, left fat pad) or the full length copGFP gene (D, right fat pad). Fluorescence was
visualized by microscopy (x400). E. Visualization of Abcg1 (red) by fluorescence microscopy (x63) in
epididymal fat pads following the local injection in the epididymal adipose tissue of lentiviral particles
encoding either a shRNA control or a shRNA inhibiting mouse Abcg1 expression. Nuclei were
counterstained with DAPI (blue). Quantification of Abcg1 mRNA levels in (F) adipose tissue (mean Ct :
25,18 in L-Ctrl), (H) intestine (mean Ct : 31.78 in L-Ctrl) and (I) liver (mean Ct : 29.95 in L-Ctrl) from
C57BL/6 mice fed a high fat diet (60% fat) after 4 weeks following the local injection in the epididymal
adipose tissue of lentiviral particles encoding either a shRNA inhibiting mouse Abcg1 expression (L-
Abcg1) or a shRNA control (L-Ctrl). G. Quantification of Abcg1 mRNA levels in adipocytes (mean Ct :
27.95 in L-Ctrl), adipose tissue macrophages (ATM, mean Ct : 31.01 in L-Ctrl) and endothelial cells
(mean Ct : 30.15 in L-Ctrl) isolated in adipose tissue from L-Abcg1 and L-Ctrl mice. n=11 mice per
group. Data are shown as mean ± SEM. *p<0.05 and ***p<0.0005 versus L-Ctrl.
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Figure 6. Abcg1 deficiency in adipose tissues affects high-fat feeding response of mice.
C57BL/6 mice fed a high fat diet (40% fat) were injected with lentiviral particles encoding either a
shRNA inhibiting mouse Abcg1 expression (L-Abcg1) or a shRNA control (L-Ctrl) locally in the
epididymal adipose tissue. (A) Weight gain, (B) epididymal fat mass, (C) adipocyte diameter and (D,
H-O) mRNA levels in epididymal adipose tissue was measured after 4 weeks following the day of the
injection (n=10 mice per group). (E) Food intake were measured in C57BL/6 mice fed a high fat diet
(60% fat) after 4 weeks following the local injection in the epididymal adipose tissue of lentiviral
particles encoding either a shRNA inhibiting mouse Abcg1 expression (L-Abcg1, n=6) or a shRNA
control (L-Ctrl, n=6). (F-G) Locomotor activity in L-Ctrl (n=8) and L-Abcg1 (n=8) mice was monitored
throughout the 4 weeks following the injection. Data are shown as mean ± SEM. *p<0.05 and
**p<0.005 versus L-Ctrl.
Figure 7. Elevated adipose tissue ABCG1 expression and increased fat mass and obesity in
obese individuals carrying the AT haplotype. A. Human ABCG1 promoter activity according to the
CG and AT haplotypes. HepG2 cells were transiently transfected with a construct containing the
proximal 1056 bp of the human promoter with either the -204A / -134T (AT) haplotype or the -204C / -
134G (CG) haplotype. Luciferase activity is expressed in RLU after normalization for β-galactosidase
activity. Values are means±SEM of 5 independent experiments performed in triplicate. *p<0.0005. B-F.
Quantification of mRNA levels isolated in adipose tissue biopsies from 10 morbid obese women
carrying either the AT or the CG haplotype. (G) Correlation between adipocyte diameter and ABCG1
mRNA levels in adipose tissue from morbid obese women. n=20. Fat mass (H) and fat-free mass (I) in
obese individuals carrying either the AT (n=102) or the CG haplotype (n=22). Data are shown as mean
± SEM. *p<0.05 versus CG haplotype, adjusted for age and sex. Association of the rs1378577 (-
134T/G) and rs1893590 (-204A/C) ABCG1 SNP with (J) BMI (L) and fat mass index (FMI) in a
population of 1320 middle-aged severely morbid obese patients (BMI = 45.47 ± 0.002 Kg/m2). (K)
Amount of -204A / -134T (AT) haplotypes relative to BMI in obese individuals. AT/AT = 2. The effect of
each SNP on BMI was analyzed by linear regression in an additive, dominant and recessive manner.
The best model fitting the data is shown (dominant). All models were adjusted for age and sex. Data
are shown as mean ± SEM. *p<0.05.
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Supplementary Table 1. Metabolic consequences of epididymal adipose tissue Abcg1 knockdown in C57BL/6 mice fed a high fat diet.
Data represent Mean ± S.E.M. of L-Ctrl (n=16) and L-Abcg1 (n=21) mice at 4 weeks following the injection of lentiviral particle. p value versus L-Ctrl.
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Supplementary Table 2. Association of rs1378577 and rs1893590 ABCG1 SNPs with BMI in a population of 1320 middle-aged morbid obese patients.
ABCG1 SNP BMI (kg/m²) BMI (kg/m²) /
diabetes BMI (kg/m²) /
HOMA2B BMI (kg/m²) /
HOMA2S BMI.kg.m.² / HOMA2IR
rs1378577 G/G vs G/T P value 0,40474 0,284993 0,32257 0,35605 0,63625 G/G vs G/T β -0,92 -1,02 -0,91 -0,83 -0,33 G/G vs T/T P value 0,55378 0,43940 0,40062 0,35993 0,22551 G/G vs T/T β 0,65 1,31 1,38 1,46 1,80 G/T vs T/T P value 0,00232** 0,00017*** 0,00019*** 0,00018*** 0,00029*** G/T vs T/T β -1,57 -2,33 -2,30 -2,29 -2,13
rs1893590 A/A vs A/C P value 0,04237* 0,02776* 0,03007* 0,03363* 0,04308* A/A vs A/C β -1,08 -1,43 -1,41 -1,37 -1,25 A/A vs C/C P value 0,01958* 0,01022* 0,00883* 0,00989* 0,00758* A/A vs C/C β -2,15 -2,72 -2,75 -2,70 -2,80 A/C vs C/C P value 0,27832 0,28020 0,25157 0,25539 0,17610 A/C vs C/C β 1,074 1,28 1,34 1,32 1,56
rs1378577
G/G vs G/T & T/T P value 0,95916 0,54119 0,916 0,8569 0,8 G/G vs G/T & T/T β 0,06 1,05 0,48 0,57 0,65 G/G & G/T vs T/T P value 0,00339** 0,00026*** 0,00031*** 0,00031*** 0,00027*** G/G & G/T vs T/T β 1,45 2,09 2,17 2,16 2,17
rs1893590
A/A & A/C vs C/C P value 0,06083 0,02497* 0,0379* 0,03258* 0,0349* A/A & A/C vs C/C β -1,69 -2,32 -2,16 -2,21 -2,17 A/A vs A/C & C/C P value 0,01102* 0,00693* 0,00471** 0,00477** 0,00561* A/A vs A/C & C/C β -1,29 -1,59 -1,74 -1,73 -1,69
All analysis were adjusted for age and sex. β, regression coefficient. *p<0.05, **p<0.005 and ***p<0.0005. Association of ABCG1 SNPs with BMI was adjusted for diabetes or HOMA index (HOMA2B, HOM2S and HOMAIR).
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Supplementary Table 3. Association of rs1378577 and rs1893590 ABCG1 SNPs with plasma lipid and apolipoprotein levels in a population of 1320 middle-aged morbid obese patients.