Peroxisome Proliferator-activated Receptor γ Activation Promotes Infiltration of Alternatively Activated Macrophages into Adipose Tissue

Obesity is associated with infiltration of macrophages into adipose tissue. Adipose macrophages may contribute to an elevated inflammatory status by secreting a variety of proinflammatory mediators, including tumor necrosis factor α and interleukin-6 (IL-6). Recent data suggest that during diet-induced obesity the phenotype of adipose-resident macrophages changes from alternatively activated macrophages toward a more classical and pro-inflammatory phenotype. Here, we explore the effect of peroxisome proliferator-activated receptor γ activation on obesity-induced inflammation in 129SV mice fed a high fat diet for 20 weeks. High fat feeding increased bodyweight gain, adipose tissue mass, and liver triglycerides. Rosiglitazone treatment further increased adipose mass, reduced liver triglycerides, and changed adipose tissue morphology toward smaller adipocytes. Surprisingly, rosiglitazone markedly increased the number of macrophages in adipose tissue, as shown by immunohistochemical analysis and quantification of macrophage marker genes CD68 and F4/80+. In adipose tissue, markers for classically activated macrophages including IL-18 were down-regulated, whereas markers characteristic for alternatively activated macrophages (arginase 1, IL-10) were up-regulated by rosiglitazone. Importantly, conditioned media from rosiglitazone-treated alternatively activated macrophages neutralized the inhibitory effect of macrophages on 3T3-L1 adipocyte differentiation, suggesting that alternatively activated macrophages may be involved in mediating the effects of rosiglitazone on adipose tissue morphology and mass. Our results suggest that short term rosiglitazone treatment increases infiltration of alternatively activated macrophages in adipose tissue. The alternatively activated macrophages might play a role in peroxisome proliferator-activated receptorγ-dependent expansion and remodeling of adipose tissue. Obesity is associated with infiltration of macrophages into adipose tissue. Adipose macrophages may contribute to an elevated inflammatory status by secreting a variety of proinflammatory mediators, including tumor necrosis factor α and interleukin-6 (IL-6). Recent data suggest that during diet-induced obesity the phenotype of adipose-resident macrophages changes from alternatively activated macrophages toward a more classical and pro-inflammatory phenotype. Here, we explore the effect of peroxisome proliferator-activated receptor γ activation on obesity-induced inflammation in 129SV mice fed a high fat diet for 20 weeks. High fat feeding increased bodyweight gain, adipose tissue mass, and liver triglycerides. Rosiglitazone treatment further increased adipose mass, reduced liver triglycerides, and changed adipose tissue morphology toward smaller adipocytes. Surprisingly, rosiglitazone markedly increased the number of macrophages in adipose tissue, as shown by immunohistochemical analysis and quantification of macrophage marker genes CD68 and F4/80+. In adipose tissue, markers for classically activated macrophages including IL-18 were down-regulated, whereas markers characteristic for alternatively activated macrophages (arginase 1, IL-10) were up-regulated by rosiglitazone. Importantly, conditioned media from rosiglitazone-treated alternatively activated macrophages neutralized the inhibitory effect of macrophages on 3T3-L1 adipocyte differentiation, suggesting that alternatively activated macrophages may be involved in mediating the effects of rosiglitazone on adipose tissue morphology and mass. Our results suggest that short term rosiglitazone treatment increases infiltration of alternatively activated macrophages in adipose tissue. The alternatively activated macrophages might play a role in peroxisome proliferator-activated receptorγ-dependent expansion and remodeling of adipose tissue. The global prevalence rate of obesity is rising steadily (1Hill J.O. Endocr. Rev. 2006; 27: 750-761Crossref PubMed Scopus (426) Google Scholar). Obesity is linked to several metabolic disturbances that greatly increase morbidity risk, which are collected in the metabolic syndrome and include hypertension, dyslipidemia, and insulin resistance (2Reaven G.M. Am. J. Clin. Nutr. 2006; 83: 1237-1247Crossref PubMed Scopus (370) Google Scholar). Each serves as an independent risk factor for atherosclerosis and associated coronary heart disease. Although the overall negative impact of obesity and metabolic syndrome on morbidity is evident, it has been very difficult to get a handle on why some individuals are obese seemingly without any damaging consequences for health, whereas others are afflicted by a range of metabolic abnormalities. Clearly, our understanding of the chain of events that leads to metabolic syndrome, although growing, is still remarkably scarce. Recent studies suggest an important role for inflammatory processes. Indeed, it has been found that obesity is associated with a state of chronic low grade inflammation which is likely caused by adipocyte hypertrophy together with infiltration of macrophages into adipose tissue (3Hotamisligil G.S. Nature. 2006; 444: 860-867Crossref PubMed Scopus (6390) Google Scholar). As a result, the secretion of pro-inflammatory mediators such as tumor necrosis factor α and IL-6 3The abbreviations used are:ILinterleukinPPARperoxisome proliferator-activated receptorqPCRquantitative PCRLFDlow fat dietHFDlow fat dietFCSfetal calf serum. from adipose tissue is increased, leading to disruption of normal homeostatic control of metabolism either locally or systemically (4Weisberg S.P. McCann D. Desai M. Rosenbaum M. Leibel R.L. Ferrante Jr., A.W. J. Clin. Investig. 2003; 112: 1796-1808Crossref PubMed Scopus (7562) Google Scholar, 5Xu H. Barnes G.T. Yang Q. Tan G. Yang D. Chou C.J. Sole J. Nichols A. Ross J.S. Tartaglia L.A. Chen H. J. Clin. Investig. 2003; 112: 1821-1830Crossref PubMed Scopus (5240) Google Scholar, 6Kanda H. Tateya S. Tamori Y. Kotani K. Hiasa K. Kitazawa R. Kitazawa S. Miyachi H. Maeda S. Egashira K. Kasuga M. J. Clin. Investig. 2006; 116: 1494-1505Crossref PubMed Scopus (1999) Google Scholar). Why macrophages infiltrate adipose tissue during obesity is currently unclear, although it has been suggested that macrophage localization and infiltration is strongly linked to adipose cell death (7Cinti S. Mitchell G. Barbatelli G. Murano I. Ceresi E. Faloia E. Wang S. Fortier M. Greenberg A.S. Obin M.S. J. Lipid Res. 2005; 46: 2347-2355Abstract Full Text Full Text PDF PubMed Scopus (1792) Google Scholar). More recently, it has been proposed that adipose tissue resident macrophages itself undergo phenotypic changes during obesity. In adipose tissue of mice rendered obese by high fat feeding, macrophages appear to be mainly activated according to “classical activation,” whereas macrophages present in adipose tissue of lean mice are “alternatively activated” (8Lumeng C.N. Bodzin J.L. Saltiel A.R. J. Clin. Investig. 2007; 117: 175-184Crossref PubMed Scopus (3401) Google Scholar). Classically activated macrophages express high levels of pro-inflammatory mediators including tumor necrosis factor α, which may contribute to insulin resistance. In contrast, alternatively activated macrophages are considered anti-inflammatory by expressing genes such as IL-10, IL-1 receptor antagonist, and arginase I (9Gordon S. Nat. Rev. Immunol. 2003; 3: 23-35Crossref PubMed Scopus (4782) Google Scholar). interleukin peroxisome proliferator-activated receptor quantitative PCR low fat diet low fat diet fetal calf serum. The peroxisome proliferator-activated receptor γ is a ligand-activated transcription factor and member of the superfamily of nuclear receptors. It regulates gene transcription by binding to specific DNA sequences in target genes, leading to chromatin remodeling and activation of gene transcription. PPARγ serves as the molecular target for an important class of anti-diabetic drugs, the thiazolidinediones. In addition, PPARγ binds and is activated by polyunsaturated fatty acids and fatty acid-derived molecules. The expression of PPARγ is highest in adipose tissues, where it plays a pivotal role in the adipocyte differentiation and lipid storage (10Rosen E.D. Sarraf P. Troy A.E. Bradwin G. Moore K. Milstone D.S. Spiegelman B.M. Mortensen R.M. Mol. Cell. 1999; 4: 611-617Abstract Full Text Full Text PDF PubMed Scopus (1669) Google Scholar, 11Koutnikova H. Cock T.A. Watanabe M. Houten S.M. Champy M.F. Dierich A. Auwerx J. Proc. Natl. Acad. Sci. U. S. A. 2003; 100: 14457-14462Crossref PubMed Scopus (161) Google Scholar). PPARγ is also relatively well expressed in macrophages. Target genes of PPARγ identified so far include fatty acid-binding protein 4, GLUT4, glycogen synthase 2, glycerol-3-phosphate dehydrogenase, lipoprotein lipase, glycerol kinase, and aquaporin 7 (12Lehrke M. Lazar M.A. Cell. 2005; 123: 993-999Abstract Full Text Full Text PDF PubMed Scopus (1180) Google Scholar, 13Mandard S. Stienstra R. Escher P. Tan N.S. Kim I. Gonzalez F.J. Wahli W. Desvergne B. Muller M. Kersten S. Cell. Mol. Life Sci. 2007; 64: 1145-1157Crossref PubMed Scopus (60) Google Scholar). As mentioned above, PPARγ is the molecular target for the insulin-sensitizing thiazolidinediones, which effectively lower plasma glucose and insulin levels by promoting insulin sensitivity and, thus, stimulating glucose uptake. Thiazolidinediones also reduce plasma free fatty acid concentrations, although this effect is mainly evident in rodents (14Oakes N.D. Thalen P.G. Jacinto S.M. Ljung B. Diabetes. 2001; 50: 1158-1165Crossref PubMed Scopus (159) Google Scholar, 15Tan G.D. Fielding B.A. Currie J.M. Humphreys S.M. Desage M. Frayn K.N. Laville M. Vidal H. Karpe F. Diabetologia. 2005; 48: 83-95Crossref PubMed Scopus (95) Google Scholar). In addition to its role in adipocyte differentiation and glucose metabolism, PPARγ also has potent anti-inflammatory activity. Treatment of mice with rosiglitazone causes a significant decrease in expression of numerous inflammatory mediators, including tumor necrosis factor α and IL-6 (16Hammarstedt A. Andersson C.X. Rotter S.V. Smith U. Prostaglandins Leukot. Essent. Fatty Acids. 2005; 73: 65-75Abstract Full Text Full Text PDF PubMed Scopus (103) Google Scholar). In adipose tissue, induction of adipocyte differentiation by PPARγ is paralleled by the appearance of smaller adipocytes (17Okuno A. Tamemoto H. Tobe K. Ueki K. Mori Y. Iwamoto K. Umesono K. Akanuma Y. Fujiwara T. Horikoshi H. Yazaki Y. Kadowaki T. J. Clin. Investig. 1998; 101: 1354-1361Crossref PubMed Scopus (927) Google Scholar), which may partially account for the inhibitory effect of PPARγ on inflammatory gene expression (18Jernas M. Palming J. Sjoholm K. Jennische E. Svensson P.A. Gabrielsson B.G. Levin M. Sjogren A. Rudemo M. Lystig T.C. Carlsson B. Carlsson L.M. Lonn M. FASEB J. 2006; 20: 1540-1542Crossref PubMed Scopus (357) Google Scholar). Furthermore, it has been suggested that PPARγ may suppress inflammation associated with diet-induced obesity by lowering the number of macrophages present in adipose tissue (5Xu H. Barnes G.T. Yang Q. Tan G. Yang D. Chou C.J. Sole J. Nichols A. Ross J.S. Tartaglia L.A. Chen H. J. Clin. Investig. 2003; 112: 1821-1830Crossref PubMed Scopus (5240) Google Scholar, 19Bodles A.M. Varma V. Yao-Borengasser A. Phanavanh B. Peterson C.A. McGehee Jr., R.E. Rasouli N. Wabitsch M. Kern P.A. J. Lipid Res. 2006; 47: 2080-2088Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar). The aim of the present study was to examine the effect of rosiglitazone on macrophage infiltration in Sv129 mice rendered obese by chronic feeding of a high fat diet. Our data indicate that short term rosiglitazone treatment increases infiltration of alternatively activated macrophages in adipose tissue. Animal Study—Sv129 male mice were purchased at The Jackson Laboratory (Bar Harbor, ME). Male mice received a low fat diet (LFD) or low fat diet (HFD) for 21 weeks, providing 10 or 45% energy percent in the form of triglycerides (D12450B or D12451, Research Diets, New Brunswick, NJ). The lard component in these diets was replaced by palm oil. In the last week of diet intervention, half of the mice receiving the HFD were switched to HFD supplemented with rosiglitazone (0.01% w/w). At the end of the feeding experiment, blood was collected in EDTA-coated tubes and centrifuged at 10,000 × g to collect plasma. Liver and epididymal white adipose tissue were dissected, weighed, and immediately frozen in liquid nitrogen. The animal experiments were approved by the animal experimentation committee of Wageningen University. Microarray Analysis, RNA Isolation, and Quality Control—Total RNA was isolated from adipose tissue or 3T3-L1 adipocytes using TRIzol reagent (Invitrogen) according to the manufacturer’s instructions. Concentrations and purity of RNA samples were determined on a NanoDrop ND-1000 spectrophotometer (Isogen, Maarssen, The Netherlands). RNA integrity was checked on an Agilent 2100 bioanalyzer (Agilent Technologies, Amsterdam, the Netherlands) with 6000 Nano Chips. Pooled RNA samples from five mice per experimental group were used for microarray were on levels were the for M. N.D. M. 2005; PubMed Scopus Google and a M. Wang P. G. B. R.M. H. F. Res. 2005; PubMed Scopus Google Scholar). of the are on Microarray data were to the gene expression and data The number is was used to the changed using of a or and a to or of RNA was used for transcription using the PCR was with (Invitrogen) and using an PCR analysis was to a PCR was The used are in The expression of genes was to gene sequences used for in a of an was were with normal by at with the in with the a to was used as a of the was using for were used by the and of was using The of for was as the of the number of of by the number of present in a per were and a of or mice per group were of fat was using were in × of fat was by a on results of were the the and were The is fat are fat in of were fat were per were using analysis of significant was for were using DNA of adipose tissue, were with for at were using a Liver triglycerides were determined in liver in and 10 at using a from The Netherlands). and levels of insulin were using a from Research levels of were using a from of Adipose isolated epididymal adipose tissue was used for the of adipocytes and adipose tissue was using at a of in with were for at and a the were collected as and the were collected as cell were with and RNA was isolated using reagent were from the of and in and were with rosiglitazone or for was and were using and with without the addition of was from and at further 3T3-L1 were in calf and for differentiation in the was changed to and the were and insulin the was changed to and insulin the was changed to which was changed of adipocytes was using a significant were using The for was at a of or Rosiglitazone Treatment of Adipose with of PPARγ Target mice were fed a or HFD for 20 weeks. Although energy was mice on HFD a bodyweight with mice on Adipose tissue at the end of the study was also in the HFD week of rosiglitazone treatment of mice fed the HFD further increased adipose tissue and plasma HFD also increased plasma insulin suggesting of insulin resistance as well as liver triglycerides which were by rosiglitazone. The increase in adipose tissue and decrease in liver strongly of liver fat toward white adipose tissue rosiglitazone Rosiglitazone also caused a increase in the expression of several PPARγ target genes in adipose tissue including and In with an overall in adipocyte was rosiglitazone treatment in the appearance of smaller adipocytes and Rosiglitazone Treatment an increase in adipose mass, rosiglitazone treatment of of as by nuclear suggesting the of cell The of strongly that are by macrophages in adipose tissue of obese mice (7Cinti S. Mitchell G. Barbatelli G. Murano I. Ceresi E. Faloia E. Wang S. Fortier M. Greenberg A.S. Obin M.S. J. Lipid Res. 2005; 46: 2347-2355Abstract Full Text Full Text PDF PubMed Scopus (1792) Google Scholar). more macrophages were present in adipose tissue rosiglitazone immunohistochemical using the specific macrophage marker was As shown in rosiglitazone increased suggesting more macrophages were results were by quantitative analysis of the number of macrophages present in adipose tissue and gene expression analysis of and macrophage specific gene In with an increased macrophage expression of was up-regulated by rosiglitazone in adipose tissue data suggest that short term rosiglitazone treatment macrophage infiltration in adipose tissue of obese plasma of were elevated rosiglitazone treatment and a toward a decrease suggesting that expression is increased examine the effect of rosiglitazone and the increased of macrophages on global adipose gene microarray analysis was in fed HFD with or without rosiglitazone. As rosiglitazone changed genes involved in lipid metabolism and energy More cell tissue and tissue were rosiglitazone suggesting changes in adipose tissue and Rosiglitazone Adipose of either be activated by γ and by activation The which is by and a macrophage phenotype with tissue and remodeling and of inflammation (9Gordon S. Nat. Rev. Immunol. 2003; 3: 23-35Crossref PubMed Scopus (4782) Google Scholar). the effects of rosiglitazone on adipose tissue macrophage the expression of several macrophage markers was determined in adipose tissue adipose expression of arginase 1, and IL-10, which are markers characteristic of alternatively activated macrophages (9Gordon S. Nat. Rev. Immunol. 2003; 3: 23-35Crossref PubMed Scopus (4782) Google Scholar, K. J.M. A.M. J. Immunol. PubMed Scopus Google Scholar, S. M. A. J. Immunol. 2006; PubMed Scopus Google Scholar), were increased by rosiglitazone In contrast, expression of a linked to the classical activation of macrophages J. 2001; Scopus Google Scholar), was by rosiglitazone. levels of and IL-6 were also by although the to Rosiglitazone adipose expression levels of suggesting in the number of pro-inflammatory classically macrophages (8Lumeng C.N. Bodzin J.L. Saltiel A.R. J. Clin. Investig. 2007; 117: 175-184Crossref PubMed Scopus (3401) Google Scholar). the changes in adipose tissue gene expression were specific for the adipose tissue adipose tissue from was into and adipocytes. As was expressed in the adipocyte In the rosiglitazone up-regulated expression of arginase I and In contrast, rosiglitazone expression of changes in expression of markers genes in in white adipose tissue. these data suggest that rosiglitazone increases the of alternatively activated macrophages in adipose tissue. It has been that alternatively activated macrophages cell (9Gordon S. Nat. Rev. Immunol. 2003; 3: 23-35Crossref PubMed Scopus (4782) Google Scholar). As mentioned above, global analysis of gene expression by microarray that rosiglitazone expression of genes to cell and tissue morphology we expression levels of and in white adipose tissue. expression of genes was increased by suggesting increased cell in adipose tissue of obese mice PPARγ activation from and the of on week of rosiglitazone treatment was associated with a significant increase in adipose tissue adipocyte the effect of rosiglitazone on adipose tissue morphology and may be partially changes in the macrophage the effect of alternatively activated macrophages on was The alternatively activated phenotype was in by with which arginase and PPARγ expression In addition, were with rosiglitazone. conditioned from macrophages with either rosiglitazone was to 3T3-L1 adipocytes. from macrophages strongly 3T3-L1 adipocyte differentiation and expression of marker genes with normal with conditioned from from or rosiglitazone-treated macrophages markedly 3T3-L1 adipocyte differentiation more induction was using conditioned from macrophages with and rosiglitazone. The effect was by a significant increase in expression of marker genes data suggest that rosiglitazone may the inhibitory effect of macrophages on adipocyte differentiation a alternatively activated macrophages. Obesity is associated with the infiltration of macrophages into adipose tissue, which may contribute to an elevated inflammatory status by secreting a variety of pro-inflammatory mediators, including tumor necrosis factor α and has been identified as an important for the of macrophages into adipose tissue H. Tateya S. Tamori Y. Kotani K. Hiasa K. Kitazawa R. Kitazawa S. Miyachi H. Maeda S. Egashira K. Kasuga M. J. Clin. Investig. 2006; 116: 1494-1505Crossref PubMed Scopus (1999) Google Scholar, S.P. D. R. J. S. K. I. Leibel R.L. Ferrante Jr., A.W. J. Clin. Investig. 2006; 116: PubMed Scopus Google Scholar). studies suggest that PPARγ may obesity-induced inflammation in adipose tissue several R. M. Kersten S. Res. 2007; PubMed Scopus Google including of and proinflammatory genes (5Xu H. Barnes G.T. Yang Q. Tan G. Yang D. Chou C.J. Sole J. Nichols A. Ross J.S. Tartaglia L.A. Chen H. J. Clin. Investig. 2003; 112: 1821-1830Crossref PubMed Scopus (5240) Google Scholar), of adipose-resident macrophages A.M. Varma V. Yao-Borengasser A. Phanavanh B. Peterson C.A. McGehee Jr., R.E. Rasouli N. Wabitsch M. Kern P.A. J. Lipid Res. 2006; 47: 2080-2088Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar), and the morphology of adipose tissue toward smaller adipocytes M. H. J. Y. A. D. Y. Am. J. PubMed Scopus Google Scholar). In to in our study treatment with rosiglitazone was associated with a increase in the number of macrophages present in adipose tissue, as by and of expression of macrophages markers In of these we found that rosiglitazone increased expression of in adipose tissue leading to an of and macrophages. is in to data a of expression in adipocytes PPARγ activation J.M. A.S. B. J. Clin. 2005; PubMed Scopus Google Scholar). results in this study were using isolated adipose tissue. In addition, activation of PPARγ might effects in obese lean treatment of lean mice with rosiglitazone might reduce short term PPARγ activation in obese might to increased expression and an of macrophages. macrophages are involved in remodeling of adipose tissue to the of triglycerides from it was that obesity leads to of adipose-resident macrophages toward a phenotype. macrophages levels of pro-inflammatory genes and likely contribute to obesity-induced inflammation (8Lumeng C.N. Bodzin J.L. Saltiel A.R. J. Clin. Investig. 2007; 117: 175-184Crossref PubMed Scopus (3401) Google Scholar). The increased expression of arginase I and and expression of IL-18 in rosiglitazone-treated is of of adipose macrophages toward an phenotype. In to our has been to mainly macrophages 2007; Full Text Full Text PDF PubMed Scopus Google Scholar). it has been suggested that and macrophages from phenotype to (9Gordon S. Nat. Rev. Immunol. 2003; 3: 23-35Crossref PubMed Scopus (4782) Google Scholar). The increased adipose expression of rosiglitazone treatment might to a of macrophages. the by the activation of PPARγ might a from toward macrophages infiltration of the adipose tissue. In as as or alternatively activated macrophages mainly anti-inflammatory the in macrophage phenotype may be partially for the of inflammatory gene expression by rosiglitazone. It be that changes in macrophage may contribute to remodeling and expansion of adipose tissue. activated macrophages been linked to tissue and cell Indeed, experiments shown that alternatively activated macrophages of E. N. M. B. Wang M. M.S. Immunol. PubMed Scopus Google Scholar). to our rosiglitazone expression of genes to cell and tissue including and B. The increase in cell genes is the of increased of alternatively activated macrophages in adipose tissue of gene expression by we that conditioned from alternatively activated macrophages with rosiglitazone neutralized the inhibitory effect of conditioned from macrophages on 3T3-L1 it that the from classical to alternatively activated macrophages may the effects of rosiglitazone on adipose tissue remodeling and PPARγ is well expressed in adipocytes and macrophages. our study it is to any the role of macrophages adipocyte PPARγ in mediating the effect of rosiglitazone on macrophage as well as on macrophage this was in were the role of macrophage PPARγ in the of obesity-induced inflammation and insulin resistance using PPARγ mice V. A.R. D. F. Ferrante A.W. A. Nature. 2007; PubMed Scopus Google Scholar, J.M. D. G. M.A. B. S. Gonzalez F.J. M. J. Clin. Investig. 2007; 117: PubMed Scopus Google Scholar). HFD feeding the PPARγ mice more macrophages were present in adipose tissue V. A.R. D. F. Ferrante A.W. A. Nature. 2007; PubMed Scopus Google Scholar). our expression of markers of alternatively activated macrophages in adipose tissue was strongly in PPARγ in which likely for the increase in inflammatory gene including IL-6 and Importantly, the of PPARγ in macrophages insulin data suggest that macrophage PPARγ plays a role in macrophage in adipose tissue, of inflammatory mediators as well as in mediating the effect of on insulin In with data a decrease in adipose tissue macrophage term rosiglitazone treatment to A.M. Varma V. Yao-Borengasser A. Phanavanh B. Peterson C.A. McGehee Jr., R.E. Rasouli N. Wabitsch M. Kern P.A. J. Lipid Res. 2006; 47: 2080-2088Abstract Full Text Full Text PDF PubMed Scopus (64) Google Scholar), our data suggest that short term treatment increases the adipose of alternatively activated macrophages. studies the effects of short term rosiglitazone short term to rosiglitazone macrophage treatment might to of macrophages adipose tissue remodeling and In we that short term PPARγ activation in the of obesity macrophage infiltration into adipose tissue inflammatory gene The of the macrophages is alternatively activated and may play an important role in adipose tissue remodeling and for with the animal