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Smith JD, Cianflone K, Dewailly E, Château-Degat ML, Vohl MC, Julien P. Acylation stimulating protein is higher in Inuit from Nunavik compared to a southern Quebec population. Int J Circumpolar Health 2010; 68:421-32. [PMID: 20044961 DOI: 10.3402/ijch.v68i5.17385] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES The Inuit of Nunavik in northern Quebec have a lower risk for ischemic heart disease (IHD) compared to Caucasian populations. Acylation stimulating protein (ASP), which is involved in the storage of dietary fat, may play a role. The objective of the study was to determine plasma concentration of ASP in an Inuit and a southern Quebec Caucasian population. STUDY DESIGN This is a cross-sectional study evaluating the relationship between ASP and dietary factors, such as retinol, whose intake is higher in the Inuit. As well, concentrations of ASP were evaluated in relationship to components of the metabolic syndrome. METHODS Medical history was collected via a questionnaire and anthropometric measurements and blood samples were collected. RESULTS ASP was significantly higher in both the Inuit men and women compared to Caucasian men (66.1 +/- 4.1 nM vs 27.5 +/- 2.5 nM, p < 0.0001) and women (71.8 +/- 3.8 nM vs 29.4 +/- 1.3 nM, p < 0.0001). In addition, ASP significantly correlated with total retinol (r = 0.17, p = 0.02) and free retinol (r = 0.15, p = 0.04) in Inuit men but not with other distinctive dietary markers such as omega-3 fatty acids. CONCLUSIONS Inuit men and women have higher ASP which was unrelated to the number of risk factors for IHD that were present.
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Affiliation(s)
- Jessica D Smith
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Y2186, 2725 Chemin Ste-foy, Ste-Foy G1V 4G5, Canada
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Choi S, Kim J, Yea K, Suh PG, Kim J, Ryu SH. Targeted label-free quantitative analysis of secretory proteins from adipocytes in response to oxidative stress. Anal Biochem 2010; 401:196-202. [PMID: 20226157 DOI: 10.1016/j.ab.2010.03.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Accepted: 03/05/2010] [Indexed: 10/19/2022]
Abstract
Adipocytes are well known to release regulation factors associated with metabolic disorders. In particular, increased oxidative stress in adipocytes contributes to dysregulation of adipokine production. In this study, we applied relative quantitative proteomic analysis based on label-free multiple reaction monitoring (MRM) to discover biological changes of adipokines under oxidative stress. Among a total of 194 identified proteins, 8 proteins were selected and quantified between control and hydrogen peroxide (H(2)O(2))-treated groups by label-free MRM quantification. The secretion levels of matrix metalloproteinase-2 (MMP-2), stromal cell-derived factor-1 (SDF-1, CXCL12), resistin, and complement factor D (CFD, adipsin) decreased, whereas the secretion levels of tissue inhibitor of metalloproteinase-2 (TIMP-2) and aldolase A increased. Here we suggest that our study with label-free quantitative analysis will contribute to the efficient quantitative analysis of targeted proteins in complex mixtures and specifically to a better understanding of changes of adipokines under oxidative stress.
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Affiliation(s)
- Sunkyu Choi
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
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153
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MacLaren RE, Cui W, Lu H, Simard S, Cianflone K. Association of adipocyte genes with ASP expression: a microarray analysis of subcutaneous and omental adipose tissue in morbidly obese subjects. BMC Med Genomics 2010; 3:3. [PMID: 20105310 PMCID: PMC2843642 DOI: 10.1186/1755-8794-3-3] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Accepted: 01/27/2010] [Indexed: 12/22/2022] Open
Abstract
Background Prevalence of obesity is increasing to pandemic proportions. However, obese subjects differ in insulin resistance, adipokine production and co-morbidities. Based on fasting plasma analysis, obese subjects were grouped as Low Acylation Stimulating protein (ASP) and Triglyceride (TG) (LAT) vs High ASP and TG (HAT). Subcutaneous (SC) and omental (OM) adipose tissues (n = 21) were analysed by microarray, and biologic pathways in lipid metabolism and inflammation were specifically examined. Methods LAT and HAT groups were matched in age, obesity, insulin, and glucose, and had similar expression of insulin-related genes (InsR, IRS-1). ASP related genes tended to be increased in the HAT group and were correlated (factor B, adipsin, complement C3, p < 0.01 each). Differences between LAT and HAT group were almost exclusively in SC tissue, with little difference in OM tissue. Increased C5L2 (p < 0.01), an ASP receptor, in HAT suggests a compensatory ASP pathway, associated with increased TG storage. Results HAT adipose tissue demonstrated increased lipid related genes for storage (CD36, DGAT1, DGAT2, SCD1, FASN, and LPL), lipolysis (HSL, CES1, perilipin), fatty acid binding proteins (FABP1, FABP3) and adipocyte differentiation markers (CEBPα, CEBPβ, PPARγ). By contrast, oxidation related genes were decreased (AMPK, UCP1, CPT1, FABP7). HAT subjects had increased anti-inflammatory genes TGFB1, TIMP1, TIMP3, and TIMP4 while proinflammatory PIG7 and MMP2 were also significantly increased; all genes, p < 0.025. Conclusion Taken together, the profile of C5L2 receptor, ASP gene expression and metabolic factors in adipose tissue from morbidly obese HAT subjects suggests a compensatory response associated with the increased plasma ASP and TG.
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Affiliation(s)
- Robin E MacLaren
- Centre de Recherche Institut Universitaire de Cardiologie et de Pneumologie de Quebec, Laval University, Quebec, Canada
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154
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Moreno-Navarrete JM, Martínez-Barricarte R, Catalán V, Sabater M, Gómez-Ambrosi J, Ortega FJ, Ricart W, Blüher M, Frühbeck G, Rodríguez de Cordoba S, Fernández-Real JM. Complement factor H is expressed in adipose tissue in association with insulin resistance. Diabetes 2010; 59:200-9. [PMID: 19833879 PMCID: PMC2797922 DOI: 10.2337/db09-0700] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Activation of the alternative pathway of the complement system, in which factor H (fH; complement fH [CFH]) is a key regulatory component, has been suggested as a link between obesity and metabolic disorders. Our objective was to study the associations between circulating and adipose tissue gene expressions of CFH and complement factor B (fB; CFB) with obesity and insulin resistance. RESEARCH DESIGN AND METHODS Circulating fH and fB were determined by enzyme-linked immunosorbent assay in 398 subjects. CFH and CFB gene expressions were evaluated in 76 adipose tissue samples, in isolated adipocytes, and in stromovascular cells (SVC) (n = 13). The effects of weight loss and rosiglitazone were investigated in independent cohorts. RESULTS Both circulating fH and fB were associated positively with BMI, waist circumference, triglycerides, and inflammatory parameters and negatively with insulin sensitivity and HDL cholesterol. For the first time, CFH gene expression was detected in human adipose tissue (significantly increased in subcutaneous compared with omental fat). CFH gene expression in omental fat was significantly associated with insulin resistance. In contrast, CFB gene expression was significantly increased in omental fat but also in association with fasting glucose and triglycerides. The SVC fraction was responsible for these differences, although isolated adipocytes also expressed fB and fH at low levels. Both weight loss and rosiglitazone led to significantly decreased circulating fB and fH levels. CONCLUSIONS Increased circulating fH and fB concentrations in subjects with altered glucose tolerance could reflect increased SVC-induced activation of the alternative pathway of complement in omental adipose tissue linked to insulin resistance and metabolic disturbances.
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Affiliation(s)
- José María Moreno-Navarrete
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomédica de Girona, and CIBER Fisiopatologia Obesidad y Nutricion, Instituto de Salud Carlos III, Girona, Spain
| | | | - Victoria Catalán
- Department of Endocrinology and Metabolic Research Laboratory, Clínica Universitaria, University of Navarra, Pamplona, Spain, and CIBER Fisiopatologia Obesidad y Nutricion, Instituto de Salud Carlos III, Pamplona, Spain
| | - Mònica Sabater
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomédica de Girona, and CIBER Fisiopatologia Obesidad y Nutricion, Instituto de Salud Carlos III, Girona, Spain
| | - Javier Gómez-Ambrosi
- Department of Endocrinology and Metabolic Research Laboratory, Clínica Universitaria, University of Navarra, Pamplona, Spain, and CIBER Fisiopatologia Obesidad y Nutricion, Instituto de Salud Carlos III, Pamplona, Spain
| | - Francisco José Ortega
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomédica de Girona, and CIBER Fisiopatologia Obesidad y Nutricion, Instituto de Salud Carlos III, Girona, Spain
| | - Wifredo Ricart
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomédica de Girona, and CIBER Fisiopatologia Obesidad y Nutricion, Instituto de Salud Carlos III, Girona, Spain
| | - Mathias Blüher
- Department of Medicine, University of Leipzig, Leipzig, Germany
| | - Gema Frühbeck
- Department of Endocrinology and Metabolic Research Laboratory, Clínica Universitaria, University of Navarra, Pamplona, Spain, and CIBER Fisiopatologia Obesidad y Nutricion, Instituto de Salud Carlos III, Pamplona, Spain
| | | | - José Manuel Fernández-Real
- Department of Diabetes, Endocrinology and Nutrition, Institut d'Investigació Biomédica de Girona, and CIBER Fisiopatologia Obesidad y Nutricion, Instituto de Salud Carlos III, Girona, Spain
- Corresponding author: José Manuel Fernández-Real,
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Abstract
White adipose tissue is a mesenchymal tissue that begins developing in the fetus. Classically known for storing the body's fuel reserves, adipose tissue is now recognized as an endocrine organ. As such, the secretions from adipose tissue are known to affect several systems such as the vascular and immune systems and play major roles in metabolism. Numerous studies have shown nutrient or hormonal manipulations can greatly influence adipose tissue development. In addition, the associations between various disease states, such as insulin resistance and cardiovascular disease, and disregulation of adipose tissue seen in epidemiological and intervention studies are great. Evaluation of known adipokines suggests these factors secreted from adipose tissue play roles in several pathologies. As the identification of more adipokines and determination of their role in biological systems, and the interactions between adipocytes and other cells types continues, there is little doubt that we will gain a greater appreciation for a tissue once thought to simply store excess energy.
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156
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Metabolic syndrome: A review of emerging markers and management. Diabetes & Metabolic Syndrome: Clinical Research & Reviews 2009. [DOI: 10.1016/j.dsx.2009.04.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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157
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Rensen SS, Slaats Y, Driessen A, Peutz-Kootstra CJ, Nijhuis J, Steffensen R, Greve JW, Buurman WA. Activation of the complement system in human nonalcoholic fatty liver disease. Hepatology 2009; 50:1809-17. [PMID: 19821522 DOI: 10.1002/hep.23228] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
UNLABELLED Activation of the innate immune system plays a major role in nonalcoholic fatty liver disease (NAFLD). The complement system is an important component of innate immunity that recognizes danger signals such as tissue injury. We aimed to determine whether activation of the complement system occurs in NAFLD, to identify initiating pathways, and to assess the relation between complement activation, NAFLD severity, apoptosis, and inflammatory parameters. Liver biopsies of 43 obese subjects with various degrees of NAFLD and of 10 healthy controls were analyzed for deposition of complement factors C1q, mannose-binding lectin (MBL), C4d, activated C3, and membrane attack complex (MAC)-associated C9. Furthermore, hepatic neutrophil infiltration, apoptosis, and pro-inflammatory cytokine expression were quantified. Whereas complement activation was undetectable in the liver of healthy subjects, 74% of the NAFLD patients showed hepatic deposition of activated C3 and C4d. C1q as well as MBL accumulation was found in most activated C3-positive patients. Strikingly, 50% of activated C3-positive patients also displayed MAC-associated C9 deposition. Deposition of complement factors was predominantly seen around hepatocytes with macrovesicular steatosis. Subjects showing accumulation of activated C3 displayed increased numbers of apoptotic cells. Importantly, hepatic neutrophil infiltration as well as interleukin (IL)-8 and IL-6 expression was significantly higher in patients showing activated C3 deposition, whereas patients with C9 deposition additionally had increased IL-1beta expression. Moreover, nonalcoholic steatohepatitis (NASH) was more prevalent in patients showing hepatic C9 or activated C3 deposition. CONCLUSION There is widespread activation of the complement system in NAFLD, which is associated with disease severity. This may have important implications for the pathogenesis and progression of NAFLD given the function of complement factors in clearance of apoptotic cells, hepatic fibrosis, and liver regeneration.
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Affiliation(s)
- Sander S Rensen
- Department of Surgery, NUTRIM School for Nutrition, Toxicolgy, and Metabolism, Maastricht University Medical Centre, Maastricht, the Netherlands.
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158
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Trayhurn P. Obesity in the Inuit - Adipose tissue and ischaemic heart desease. Int J Circumpolar Health 2009; 68:419-420. [PMID: 28256171 DOI: 10.3402/ijch.v68i5.17601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Obesity is a major, and growing, health problemin many regions of the world. It is not, however, obesity per se that matters from a health perspective, but rather the diseases which are associatedwith it. These include type 2 diabetes, heartdisease and certain cancers. Obesity is a concernin the Inuit, as in many other groups, and datafrom the International Obesity Task Force haveindicated that Inuit men are in the top half ofnearly 80 countries and territories in the extentof overweight and obesity (1). The position isworse for Inuit women in that they rank on thesemeasures in the top quintile of over 100 countries/territories (1) .
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159
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Puchau B, Zulet MA, de Echávarri AG, Hermsdorff HHM, Martínez JA. Dietary total antioxidant capacity is negatively associated with some metabolic syndrome features in healthy young adults. Nutrition 2009; 26:534-41. [PMID: 19783122 DOI: 10.1016/j.nut.2009.06.017] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2009] [Revised: 06/03/2009] [Accepted: 06/14/2009] [Indexed: 01/04/2023]
Abstract
OBJECTIVE Oxidative stress has been related to the development of obesity and other features accompanying chronic diseases. Furthermore, dietary antioxidant intake has been suggested to protect against oxidative damage and related clinical complications. Therefore, the aim of this study was to assess the potential associations among dietary total antioxidant capacity (TAC) and several early metabolic syndrome manifestations in healthy young adults. METHODS Anthropometric variables and blood pressure from 153 healthy subjects (20.8+/-2.7 y old) were measured. Dietary intake was assessed by a validated food-frequency questionnaire and a 3-d record, which were also used to calculate TAC and to adjust by daily energy intake. Fasting blood samples were collected for measuring biochemical markers. RESULTS Dietary TAC showed positive and significant associations with fiber, folic acid, vitamin A and C, magnesium, selenium, and zinc intakes, after adjusting by sex and daily energy intake. Interestingly, systolic blood pressure, serum glucose, and free fatty acids were also found to be negatively associated with dietary TAC independently of sex and daily energy intake. Also, a relevant relation was found between body mass index and TAC values. Interestingly, after adjusting by sex and daily energy intake, complement factor-3 circulating levels appeared to be negatively and significantly associated with dietary TAC, whereas blood plasminogen activator inhibitor-1 and homocysteine concentrations showed an inverse marginally statistical trend. CONCLUSIONS These data suggest that dietary TAC may be also a potential early estimate of the risk to develop metabolic syndrome features and that dietary TAC could be a useful research tool in assessing antioxidant intake.
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Affiliation(s)
- Blanca Puchau
- Department of Nutrition, Food Science, Physiology and Toxicology, University of Navarra, Pamplona, Spain
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160
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Recombinant C3adesArg/acylation stimulating protein (ASP) is highly bioactive: a critical evaluation of C5L2 binding and 3T3-L1 adipocyte activation. Mol Immunol 2009; 46:3207-17. [PMID: 19767107 DOI: 10.1016/j.molimm.2009.08.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 08/09/2009] [Accepted: 08/12/2009] [Indexed: 11/22/2022]
Abstract
C5L2 is a recently identified receptor for C5a/C5adesArg, C3a and C3adesArg (ASP). C5a/C5adesArg bind with high affinity, with no identified activation. By contrast, some studies demonstrate C3a/ASP binding/activation to C5L2; others do not. Our aim is to critically evaluate ASP/C3adesArg-C5L2 binding and bioactivity. Cell-associated fluorescent-ASP (Fl-ASP) binding to C5L2 increased from transiently transfected<stably transfected<Fl-ASP-sorted C5L2-HEK for both human C5L2 and mouse C5L2. Transfected C5L2-CHO cells had similar results. Endogenous C5L2 expression increased from 3T3-L1 preadipocytes<3T3-L1 adipocytes<primary mouse adipocytes. Non-transfected cells+/-Fl-ASP demonstrated background fluorescence only. In adherent C5L2-HEK (Fl-ASP sorted) and 3T3-L1 cells, blocking with 10% fetal calf serum, protamine sulfate or ovalbumin prevented (125)I-ASP non-specific binding (NSB, no cells), while albumin increased NSB. Binding to non-transfected HEK was comparable to NSB. Optimal specific binding was obtained at 20 degrees C (vs. 4 degrees C) in PBS or serum-free medium with K(d) 83.7+/-23.7 nM (C5L2-HEK), 66+/-15 nM (C5L2-CHO) and 76+/-14.3 nM (3T3-L1 preadipocytes); (125)I-C5a binding had greater affinity. Fl-ASP-C5L2 binding was comparable and concentration dependent (K(d) 31 nM (direct binding) and IC(50) 35 nM (competition binding) regardless of conditions). Recombinant ASP (rASP) produced in modified Escherichia coli Origami (DE3) (allowing folding and disulphide bridge formation), purified under non-denaturing conditions demonstrated 10x greater bioactivity vs. proteolytically derived plasma ASP for triglyceride synthesis and fatty acid uptake in 3T3-L1 adipocytes and preadipocytes while adipose tissue from C5L2 KO mice was non-responsive. rASP stimulation of adipocyte BODIPY-fatty acid uptake demonstrated EC(50) 115+/-93 nM and maximal stimulation of 413+/-33%, p<0.001. ASP binding has distinct characteristics that lead to C5L2 activation and increased bioactivity.
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161
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Lago F, Gómez R, Gómez-Reino JJ, Dieguez C, Gualillo O. Adipokines as novel modulators of lipid metabolism. Trends Biochem Sci 2009; 34:500-10. [PMID: 19729309 DOI: 10.1016/j.tibs.2009.06.008] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Revised: 05/22/2009] [Accepted: 06/04/2009] [Indexed: 01/20/2023]
Abstract
In the mid-1990s, interest in adipose tissue - until then generally regarded as a mere energy reserve - was revived by the discovery of leptin. Since then numerous other cytokine-like hormones have been isolated from white adipose tissue. These adipokines have been investigated in relation to obesity, metabolic syndrome, insulin resistance and other pathological conditions and processes. In addition, it is now established that adipokines play a role in the maintenance of an inflammatory state in adipose tissue and in the development of obesity and comorbidities. The contributions of individual adipokines in the pathophysiological features of obesity have yet to be determined in full, but recent data highlight important roles for adipokines in lipid metabolism.
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Affiliation(s)
- Francisca Lago
- Research Laboratory 7 (Molecular and Cellular Cardiology), Institute of Medical Research (IDIS), University Clinical Hospital, Santiago de Compostela 15706, Spain.
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162
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C5a- and ASP-mediated C5L2 activation, endocytosis and recycling are lost in S323I-C5L2 mutation. Mol Immunol 2009; 46:3086-98. [PMID: 19615750 DOI: 10.1016/j.molimm.2009.06.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Revised: 05/26/2009] [Accepted: 06/04/2009] [Indexed: 01/10/2023]
Abstract
UNLABELLED C5L2, a G-protein-coupled receptor (GPCR), has been identified as an ASP (C3adesArg) and C5a receptor. Controversy exists regarding both ligand binding and functionality. ASP activation of C5L2 is proposed to regulate fat storage. C5L2 is also proposed as a decoy receptor for C5a, an inflammatory mediator, based on absence of Ca(2+) or chemotaxis changes. AIMS (i) to evaluate C5L2 receptor activation and recycling using recombinant ASP (rASP) and rC5a and (ii) assess receptor trafficking of S323I-C5L2 mutation previously identified in a family and demonstrated to have altered functionality. RESULTS stably transfected C5L2-HEK cells were sorted using fluorescent-ASP (Fluos-ASP) binding. Following 2-h serum-free pretreatment, C5L2 was typically localized to the cell-surface. beta-Arrestin-2-GFP transiently transfected C5L2-HEK cells demonstrated rASP and rC5a-dependent beta-arrestin-2-GFP translocation, which showed time-dependent intracellular colocalization with C5L2. Without ligand or C5L2 transfection, no translocation was identified at any time point. Ligand-dependent (rASP and rC5a) C5L2 endocytosis was time-dependent with a 1-h nadir, and was clathrin- and cholesterol-dependent. Transiently transfected Rab-GFP proteins (Rabs 5, 7 and 11) demonstrated time-dependent colocalization of Rab5, Rab7, and Rab11 with C5L2. In contrast to C5L2, a large proportion of stably transfected S323I-C5L2 did not localize to the cell-surface. While S323I-C5L2 was competent for Fluos-ASP and (125)I-ASP binding, although at a reduced level, there was no ligand-mediated receptor phosphorylation. Further, there was no ligand-mediated activation of beta-arrestin-2-GFP translocation, and no downstream functional activation of glucose transport or triglyceride synthesis. CONCLUSION C5L2 is a functional metabolic receptor, and serine 323 is important for ASP induced functionality.
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163
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Klos A, Tenner AJ, Johswich KO, Ager RR, Reis ES, Köhl J. The role of the anaphylatoxins in health and disease. Mol Immunol 2009; 46:2753-66. [PMID: 19477527 DOI: 10.1016/j.molimm.2009.04.027] [Citation(s) in RCA: 501] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2009] [Accepted: 04/28/2009] [Indexed: 12/16/2022]
Abstract
The anaphylatoxin (AT) C3a, C5a and C5a-desArg are generally considered pro-inflammatory polypeptides generated after proteolytic cleavage of C3 and C5 in response to complement activation. Their well-appreciated effector functions include chemotaxis and activation of granulocytes, mast cells and macrophages. Recent evidence suggests that ATs are also generated locally within tissues by pathogen-, cell-, or contact system-derived proteases. This local generation of ATs is important for their pleiotropic biologic effects beyond inflammation. The ATs exert most of the biologic activities through ligation of three cognate receptors, i.e. the C3a receptor, the C5a receptor and the C5a receptor-like, C5L2. Here, we will discuss recent findings suggesting that ATs regulate cell apoptosis, lipid metabolism as well as innate and adaptive immune responses through their impact on antigen-presenting cells and T cells. As we will outline, such regulatory functions of ATs and their receptors play important roles in the pathogenesis of allergy, autoimmunity, neurodegenerative diseases, cancer and infections with intracellular pathogens.
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Affiliation(s)
- Andreas Klos
- Institute of Medical Microbiology and Hospital Epidemiology, Medical School Hannover, MHH, Germany
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164
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The immunopathogenesis of alcoholic and nonalcoholic steatohepatitis: two triggers for one disease? Semin Immunopathol 2009; 31:359-69. [DOI: 10.1007/s00281-009-0152-9] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Accepted: 04/28/2009] [Indexed: 02/08/2023]
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165
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Scantlebury-Manning T, Bower J, Cianflone K, Barakat H. Racial difference in Acylation Stimulating Protein (ASP) correlates to triglyceride in non-obese and obese African American and Caucasian women. Nutr Metab (Lond) 2009; 6:18. [PMID: 19374759 PMCID: PMC2679015 DOI: 10.1186/1743-7075-6-18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Accepted: 04/17/2009] [Indexed: 12/15/2022] Open
Abstract
Background Acylation Stimulating Protein (ASP) has been shown to influence adipose tissue triglyceride (TG) storage. The aim was to examine ethnic differences in ASP and leptin levels in relation to lipid profiles and postprandial changes amongst African American (AA) and Caucasian American (CA) women matched for BMI. Methods 129 women were recruited in total (age 21 – 73 y): 24 non-obese (BMI < 30 kg/m2) CA, 27 obese (BMI ≥ 30 kg/m2) CA, 13 obese diabetic CA, 25 non-obese AA, 25 obese AA, and 15 obese diabetic AA. Cholesterol, HDL-C, LDL-C, apoB, glucose and insulin were measured at baseline. TG, non-esterified fatty acids, leptin, and ASP were measured at baseline and postprandially following a fat meal. Results ASP, leptin, insulin and TG were significantly increased in obese subjects within each race. However, AA women had significantly lower ASP and TG than CA women at all BMI. Obese and diabetic AA women had significantly lower apoB levels than CA women when compared to their respective counterparts. For AA women, fasting ASP was positively correlated with BMI, cholesterol, apoB, LDL-C and glucose. For CA women, fasting ASP was positively correlated with BMI, leptin, glucose and insulin. However, for any given BMI, ASP was significantly reduced in AA vs CA (p = 0.0004). Similarly, for any given leptin level or TG levels, ASP was significantly lower in AA women (p = 0.041 and p = 0.003, respectively). Conclusion CA women have higher baseline TG levels and an earlier TG peak that is accompanied with higher ASP levels suggesting increased ASP resistance, while AA women have lower baseline TG levels and a later TG peak at lower ASP levels suggesting increased ASP sensitivity. This may explain why AA women may have fewer metabolic complications, such as diabetes and CVD, when compared to their Caucasian counterparts at the same level of obesity.
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Affiliation(s)
- Thea Scantlebury-Manning
- Department of Biological and Chemical Sciences, Faculty of Pure and Applied Sciences, University of The West Indies, Cave Hill Campus, Bridgetown, St Michael, Barbados.
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166
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St-Pierre DH, Cianflone K, Smith J, Coderre L, Karelis AD, Imbeault P, Lavoie JM, Rabasa-Lhoret R. Change in plasma acylation stimulating protein during euglycaemic-hyperinsulinaemic clamp in overweight and obese postmenopausal women: a MONET study. Clin Endocrinol (Oxf) 2009; 70:539-46. [PMID: 18702682 DOI: 10.1111/j.1365-2265.2008.03353.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Acylation-stimulating protein (ASP) has been shown to positively stimulate fatty acid esterification and glucose uptake in adipocytes. In vitro studies demonstrate that insulin stimulates ASP secretion from adipocytes. Individuals with obesity and/or metabolic disturbances (insulin resistance and type 2 diabetes) have increased plasma ASP. DESIGN The present study was designed to evaluate whether ASP levels are influenced by the metabolic profiles of overweight and obese postmenopausal women during a euglycaemic/hyperinsulinaemic clamp (EHC). Patients The study population consisted of 76 overweight and obese sedentary postmenopausal women. MEASUREMENTS We evaluated insulin sensitivity, plasma ASP levels, body composition including visceral adipose tissue area, blood lipid profiles, liver enzymes, peak aerobic capacity, resting metabolic rate (RMR) and total energy expenditure (TEE). RESULTS We observed wide interindividual variations of ASP levels during the EHC. Therefore, subjects were divided into three groups based on ASP changes. Negative ASP Responders (NAR; n = 24) showed a -20% or greater decrease in ASP levels while Positive ASP Responders (PAR; n = 42) displayed ASP fluctuations superior to +20%. Ten subjects had little or no ASP change and were considered as Zero ASP responders (ZAR). PAR women displayed a worse metabolic profile than NAR women, including higher BMI, visceral adipose tissue, fasting insulin levels, lean body mass, and alanine aminotransferase (ALT), a marker of impaired liver function. After adjustment for BMI, only ALT remained significantly different, while lean body mass (P = 0.08) and visceral adipose tissue (P = 0.07) remained marginally higher. Correlation analysis of all subjects demonstrated that fasting ASP levels correlated positively with albumin and VO(2 peak) and this association remained significant after adjustments for the effect of BMI. In addition, the percentage maximal change in ASP levels during the EHC was positively associated with BMI, lean body mass, visceral adipose tissue, fasting insulin, HOMA, TEE, RMR, ALT and AST. CONCLUSION Overall these results suggest that an elevated ASP response during the EHC is associated with metabolic disturbances in overweight and obese postmenopausal women.
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Affiliation(s)
- David H St-Pierre
- Département de Nutrition, Université de Montréal, Montréal, Québec, Canada
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167
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Alipour A, van Oostrom AJHHM, Van Wijk JPH, Verseyden C, Plokker HWM, Jukema JW, Rabelink AJ, Castro Cabezas M. Mannose binding lectin deficiency and triglyceride-rich lipoprotein metabolism in normolipidemic subjects. Atherosclerosis 2009; 206:444-50. [PMID: 19380135 DOI: 10.1016/j.atherosclerosis.2009.03.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2008] [Revised: 02/22/2009] [Accepted: 03/05/2009] [Indexed: 11/28/2022]
Abstract
Mannose binding lectin (MBL) is one of the three initiators of complement activation and is therefore closely linked to inflammation. MBL deficiency has been associated with the generation of atherosclerosis. Since atherosclerosis, the complement system and postprandial lipemia are linked to inflammation, we studied postprandial lipoprotein metabolism in MBL deficiency. An observational study was carried out in 107 volunteers (21% MBL deficient). Classical cardiovascular risk factors were not different between subjects with and without MBL deficiency. Oral fat loading tests in 8 MBL deficient and 14 MBL sufficient subjects showed similar postprandial triglyceride, free fatty acid, hydroxybutyric acid and complement component 3 concentrations. MBL deficient subjects had 2.4 times lower postprandial Sf>400 (chylomicron)-apoB48 concentrations, but in contrast a 2-3.5 times increased Sf 60-400 (VLDL1-TG) and Sf 60-400-apoB100 response. MBL activity was inversely related to the postprandial Sf 60-400-TG increase. Despite lower postprandial Sf>400-apoB48 concentrations, MBL deficient subjects show an accumulation of Sf 60-400 lipoproteins.
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Affiliation(s)
- A Alipour
- Department of Internal Medicine, Sint Franciscus Gasthuis, Rotterdam, The Netherlands
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168
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Paglialunga S, Julien P, Tahiri Y, Cadelis F, Bergeron J, Gaudet D, Cianflone K. Lipoprotein lipase deficiency is associated with elevated acylation stimulating protein plasma levels. J Lipid Res 2009; 50:1109-19. [PMID: 19237736 DOI: 10.1194/jlr.m800430-jlr200] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Acylation stimulating protein (ASP, C3adesArg) is an adipose tissue derived hormone that stimulates triglyceride (TG) synthesis. ASP stimulates lipoprotein lipase (LPL) activity by relieving feedback inhibition caused by fatty acids (FA). The present study examines plasma ASP and lipids in male and female LPL-deficient subjects primarily with the P207L mutation, common in the population of Quebec, Canada. We evaluated the fasting and postprandial states of LPL heterozygotes and fasting levels in LPL homozygotes. Homozygotes displayed increased ASP (58-175% increase, P < 0.05-0.01), reduced HDL-cholesterol (64-75% decrease, P < 0.0001), and elevated levels of TG (19-38-fold, P < 0.0001) versus control (CTL) subjects. LPL heterozygotes with normal fasting TG (1.3-1.9 mmol/l) displayed increased ASP (101-137% increase, P < 0.05-0.01) and delayed TG clearance after a fatload; glucose levels remained similar to controls. Hypertriglyceridemics with no known LPL mutation also had increased ASP levels (63-192% increase, P < 0.001). High-TG LPL heterozygotes were administered a fatload before and after fibrate treatment. The treatment reduced fasting and postprandial plasma ASP, TG, and FA levels without changing insulin or glucose levels. ASP enhances adipose tissue fatty-acid trapping following a meal; however in LPL deficiency, high ASP levels are coupled with delayed lipid clearance.
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Affiliation(s)
- Sabina Paglialunga
- Biochemistry Department and Faculty of Medicine, McGill University, Montreal, QC, Canada
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169
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Wu G, Hu W, Shahsafaei A, Song W, Dobarro M, Sukhova GK, Bronson RR, Shi GP, Rother RP, Halperin JA, Qin X. Complement regulator CD59 protects against atherosclerosis by restricting the formation of complement membrane attack complex. Circ Res 2009; 104:550-8. [PMID: 19131645 DOI: 10.1161/circresaha.108.191361] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Complement is a central effector system within the immune system and is implicated in a range of inflammatory disorders. CD59 is a key regulator of complement membrane attack complex (MAC) assembly. The atherogenic role of terminal complement has long been suspected but is still unclear. Here, we demonstrate that among mice deficient in apolipoprotein (Apo)E, the additional loss of murine CD59 (mCd59ab(-/-)/ApoE(-/-)) accelerated advanced atherosclerosis featuring occlusive coronary atherosclerosis, vulnerable plaque, and premature death and that these effect could be attenuated by overexpression of human CD59 in the endothelium. Complement inhibition using a neutralizing anti-mouse C5 antibody attenuated atherosclerosis in mCd59ab(-/-)/ApoE(-/-) mice. Furthermore, MAC mediated endothelial damage and promoted foam cell formation. These combined results highlight the atherogenic role of MAC and the atheroprotective role of CD59 and suggest that inhibition of MAC formation may provide a therapeutic approach for the treatment of atherosclerosis.
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Affiliation(s)
- Gongxiong Wu
- Department of Medicine, Brigham and Women's Hospital, Laboratory forTranslational Research, Harvard Medical School, Cambridge, MA 02139, USA
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170
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Wu Y, Zhang J, Wen Y, Wang H, Zhang M, Cianflone K. Increased acylation-stimulating protein, C-reactive protein, and lipid levels in young women with polycystic ovary syndrome. Fertil Steril 2009; 91:213-9. [DOI: 10.1016/j.fertnstert.2007.11.031] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Revised: 11/14/2007] [Accepted: 11/14/2007] [Indexed: 11/17/2022]
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171
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Savage DB, Semple RK, Clatworthy MR, Lyons PA, Morgan BP, Cochran EK, Gorden P, Raymond-Barker P, Murgatroyd PR, Adams C, Scobie I, Mufti GJ, Alexander GJM, Thiru S, Murano I, Cinti S, Chaudhry AN, Smith KGC, O'Rahilly S. Complement abnormalities in acquired lipodystrophy revisited. J Clin Endocrinol Metab 2009; 94:10-6. [PMID: 18854390 DOI: 10.1210/jc.2008-1703] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
CONTEXT Lipodystrophy is a heterogeneous condition characterized by an inherited or acquired deficiency in the number of adipocytes required for the storage of energy as triglycerides. Acquired lipodystrophy is frequently associated with other autoimmune disorders. One well-studied form is characterized by the selective loss of upper body fat in association with activation of the alternative complement pathway by C3 nephritic factor, low complement factor C3, and mesangiocapillary glomerulonephritis. OBJECTIVE We now describe an immunologically distinct form of acquired generalized lipodystrophy, with evidence of activation of the classical complement pathway (low C4) and autoimmune hepatitis. Patients and Research Design: Three unrelated patients with acquired lipodystrophy and low complement C4 levels are described. In vitro analysis of the complement pathway was undertaken to determine the reason for the low C4 complement levels. Biopsies were obtained from liver, bone marrow, and adipose tissue for histological analysis. RESULTS All three patients manifested near-total lipodystrophy, chronic hepatitis with autoimmune features, and low C4 complement levels. Additional autoimmune diseases, including severe hemolytic anemia, autoimmune thyroid disease, and polyneuropathy, were variably present. Detailed studies of complement pathways suggested constitutive classical pathway activation. CONCLUSIONS Although the previously described syndrome, which typically results in a cephalad pattern of partial lipodystrophy, results from activation of the alternative complement pathway, this form, in which lipodystrophy is generalized, is associated with activation of the classical pathway. Future therapeutic approaches to these disorders may benefit from being tailored to their distinct immunopathogenesis.
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Affiliation(s)
- David B Savage
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, United Kingdom.
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172
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173
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Puchau B, Zulet MA, González de Echávarri A, Navarro-Blasco I, Martínez JA. Selenium intake reduces serum C3, an early marker of metabolic syndrome manifestations, in healthy young adults. Eur J Clin Nutr 2008; 63:858-64. [PMID: 18985060 DOI: 10.1038/ejcn.2008.48] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVES To evaluate the associations between serum complement factor 3 (C3) and several anthropometrical, biochemical and lifestyle features in healthy young adults, emphasizing on the putative effect of selenium intake on C3 concentrations. METHODS This study enrolled 100 healthy young adults aged 18-34 years. Anthropometric and blood pressure measurements and lifestyle features were analyzed. Fasting blood samples were collected for the measurement of glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol, triacylglycerols and C3 concentrations. Nail samples were collected for the analysis of selenium concentrations. RESULTS Values of BMI (P=0.034), sum of skinfold thicknesses (STs) (P=0.021), body fat mass (BFM) (P=0.023), percentage of overweight subjects (P=0.007), serum triacylglycerols (P=0.012) and nail selenium (P=0.001) were significantly different between subjects above and below the median of serum C3 concentrations. The following correlations with serum C3 were identified tricipital ST (P=0.033), sum of STs (P=0.012), BMI (P=0.008), BFM (P=0.018), waist-to-height ratio (P=0.016), serum glucose (P=0.045), serum triacylglycerols (P=0.001) and nail selenium (P=0.006). Circulating C3 showed a positive association with several adiposity markers such as BMI (P=0.001), waist circumference (P=0.006), waist-to-height ratio (P=0.002), BFM (P=0.025), as well as serum glucose (P=0.027) and triacylglycerols (P<0.001), whereas nail selenium was a statistically significant negative predictor of C3 concentrations (P=0.018). CONCLUSIONS C3 seems to be related with selenium status and several anthropometrical and biochemical measurements linked to metabolic syndrome in apparently healthy young adults. These findings suggest a possible role for selenium intake in the modulation of C3, whose assessment may be an early marker of metabolic syndrome manifestations.
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Affiliation(s)
- B Puchau
- Department of Nutrition and Food Sciences, Physiology and Toxicology, University of Navarra, Pamplona 31008, Spain
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174
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Jiamsripong P, Mookadam M, Honda T, Khandheria BK, Mookadam F. The Metabolic Syndrome and Cardiovascular Disease: Part I. ACTA ACUST UNITED AC 2008; 11:155-61. [DOI: 10.1111/j.1751-7141.2008.07809.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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175
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Wen Y, Wang H, MacLaren R, Lu H, Hu XF, Cianflone K. Sex steroid hormones induce acylation stimulating protein resistance in 3T3-L1 adipocytes. J Cell Biochem 2008; 105:404-13. [DOI: 10.1002/jcb.21838] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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176
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Intestinally derived lipids: Metabolic regulation and consequences—An overview. ATHEROSCLEROSIS SUPP 2008; 9:63-8. [DOI: 10.1016/j.atherosclerosissup.2008.05.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Revised: 04/03/2008] [Accepted: 05/13/2008] [Indexed: 01/17/2023]
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177
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Faraj M, Beauregard G, Tardif A, Loizon E, Godbout A, Cianflone K, Vidal H, Rabasa-Lhoret R. Regulation of leptin, adiponectin and acylation-stimulating protein by hyperinsulinaemia and hyperglycaemia in vivo in healthy lean young men. DIABETES & METABOLISM 2008; 34:334-42. [DOI: 10.1016/j.diabet.2008.01.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2007] [Revised: 01/18/2008] [Accepted: 01/25/2008] [Indexed: 10/21/2022]
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178
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Novel aspects of postprandial lipemia in relation to atherosclerosis. ATHEROSCLEROSIS SUPP 2008; 9:39-44. [PMID: 18595782 DOI: 10.1016/j.atherosclerosissup.2008.05.007] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Revised: 02/22/2008] [Accepted: 05/13/2008] [Indexed: 12/15/2022]
Abstract
Postprandial hyperlipidemia is considered to be a substantial risk factor for atherosclerosis. Interestingly, this concept has never been supported by randomized clinical trials. The difficulty lies in the fact that most interventions aimed to reduce postprandial lipemia, will also affect LDL-C levels. The atherogenic mechanisms of postprandial lipids and lipoproteins can be divided into direct lipoprotein-mediated and indirect effects; the latter, in part, by inducing an inflammatory state. Elevations in postprandial triglycerides (TG) have been related to the increased expression of postprandial leukocyte activation markers, up-regulation of pro-inflammatory genes in endothelial cells and involvement of the complement system. This set of events is part of the postprandial inflammatory response, which is one of the recently identified potential pro-atherogenic mechanisms of postprandial lipemia. Especially, complement component 3 levels show a close correlation with postprandial lipemia and are also important determinants of the metabolic syndrome. In clinical practice, fasting TG are frequently used as reflections of postprandial lipemia due to the close correlation between the two. The use of serial capillary measurements in an out-of-hospital situation is an alternative for oral fat loading tests. Daylong TG profiles reflect postprandial lipemia and are increased in conditions like the metabolic syndrome, type 2 diabetes and atherosclerosis. Studies are needed to elucidate the role of postprandial inflammation in atherogenesis and to find new methods in order to reduce selectively the postprandial inflammatory response. Future studies are needed to find new methods in order to reduce selectively the postprandial inflammatory response.
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179
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Wang P, Mariman E, Renes J, Keijer J. The secretory function of adipocytes in the physiology of white adipose tissue. J Cell Physiol 2008; 216:3-13. [PMID: 18264975 DOI: 10.1002/jcp.21386] [Citation(s) in RCA: 202] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
White adipose tissue, previously regarded as a passive lipid storage site, is now viewed as a dynamic tissue. It has the capacity to actively communicate by sending and receiving different types of signals. An overview of these signals, the external modulators that affect adipose tissue and the secreted signaling molecules, the adipokines, is presented. The secretory function is highlighted in relation to energy metabolism, inflammation and the extracellular matrix and placed in the context of adipose tissue biology. We observe that the endocrine function of adipocytes receives much attention, while its paracrine and autocrine functions are underestimated. Also, we provide examples that species specificity should not be neglected. We conclude that adipose tissue primarily is an energy storage organ, well supported by its secretory function.
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Affiliation(s)
- Ping Wang
- Functional Genomics Group, Department of Human Biology, The Nutrition and Toxicology Research Institute Maastricht (NUTRIM), Maastricht University, Maastricht, The Netherlands
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180
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Increased plasma acylation-stimulating protein in pediatric proteinuric renal disease. Pediatr Nephrol 2008; 23:959-64. [PMID: 18253759 DOI: 10.1007/s00467-007-0738-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Revised: 12/06/2007] [Accepted: 12/07/2007] [Indexed: 10/22/2022]
Abstract
Hyperlipidemia has been well recognized as a striking feature of nephrotic syndrome and other renal diseases. However, the underlying pathophysiological mechanisms still have not yet been elucidated. In this study, we evaluated acylation-stimulating protein (ASP) and complement component 3 (C3) in children (n=48) with various forms of proteinuric renal disease [nephrotic syndrome, acute poststreptococcal infection glomerulonephritis (APSGN), and lupus nephritis (LN)] in comparison with age- and gender-matched controls (n=279). In children with proteinuric renal disease, various aberrations in plasma lipids were noted, including increased triglyceride, cholesterol, and low-density lipoprotein cholesterol (LDL-C) (all p<0.0001). Whereas C3 was not altered in children with nephrotic syndrome (1.05+/-0.05 g/L vs. 1.29+/-0.04 controls), the decrease was pronounced in children with LN and APSGN (0.42+/-0.11, p<0.05 and 0.30+/-0.06, p<0.001, respectively). Plasma C3 correlated positively with lipid parameters [triglyceride, cholesterol, LDL-C, apolipoprotein B (apoB), high-density lipoprotein cholesterol (HDL-C) and apoA1] and inversely with total protein, blood urea nitrogen, and creatinine. By contrast, plasma ASP was significantly elevated in all proteinuric renal diseases (101.4+/-7.1 nmol/L nephrotic syndrome, 90.9+/-14.1 LN, and 81.8+/-7.2 APSGN vs. 44.3+/-1.5 controls, p<0.05 to p<0.001), and this increase was correlated with changes in lipid parameters (triglycerides and apoA1). In summary, these results demonstrate alterations in C3 and ASP that may contribute to or compensate for dyslipidemia.
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181
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Roy C, Paglialunga S, Fisette A, Schrauwen P, Moonen-Kornips E, St-Onge J, Hesselink MK, Richard D, Joanisse DR, Cianflone K. Shift in metabolic fuel in acylation-stimulating protein-deficient mice following a high-fat diet. Am J Physiol Endocrinol Metab 2008; 294:E1051-9. [PMID: 18398012 DOI: 10.1152/ajpendo.00689.2007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
ASP-deficient mice (C3 KO) have delayed postprandial TG clearance, are hyperphagic, and display increased energy expenditure. Markers of carbohydrate and fatty acid metabolism in the skeletal muscle and heart were examined to evaluate the mechanism. On a high-fat diet, compared with wild-type mice, C3 KO mice have increased energy expenditure, decreased RQ, lower ex vivo glucose oxidation (-39%, P = 0.018), and higher ex vivo fatty acid oxidation (+68%, P = 0.019). They have lower muscle glycogen content (-25%, P < 0.05) and lower activities for the glycolytic enzymes glycogen phosphorylase (-31%, P = 0.005), hexokinase (-43%, P = 0.007), phosphofructokinase (-51%, P < 0.0001), and GAPDH (-15%, P = 0.04). Analysis of mitochondrial enzyme activities revealed that hydroxyacyl-coenzyme A dehydrogenase was higher (+25%, P = 0.004) in C3 KO mice. Furthermore, Western blot analysis of muscle revealed significantly higher fatty acid transporter CD36 (+40%, P = 0.006) and cytochrome c (a marker of mitochondrial content; +69%, P = 0.034) levels in C3 KO mice, whereas the activity of AMP kinase was lower (-48%, P = 0.003). Overall, these results demonstrate a shift in the metabolic potential of skeletal muscle toward increased fatty acid utilization. Whether this is 1) a consequence of decreased adipose tissue storage with repartitioning toward muscle or 2) a direct result of the absence of ASP interaction with the receptor C5L2 in muscle remains to be determined. However, these in vivo data suggest that ASP inhibition could be a potentially viable approach in correcting muscle metabolic dysfunction in obesity.
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Affiliation(s)
- Christian Roy
- Centre de Recherche Hôpital Laval, Y-2186, Chemin Ste-Foy, QC, Canada
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182
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Maresh JG, Shohet RV. In vivo endothelial gene regulation in diabetes. Cardiovasc Diabetol 2008; 7:8. [PMID: 18423039 PMCID: PMC2365940 DOI: 10.1186/1475-2840-7-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Accepted: 04/19/2008] [Indexed: 02/07/2023] Open
Abstract
Background An authentic survey of the transcript-level response of the diabetic endothelium in vivo is key to understanding diabetic cardiovascular complications such as accelerated atherosclerosis and endothelial dysfunction. Methods We used streptozotocin to induce a model of type I diabetes in transgenic mice that express green fluorescent protein under the control of an endothelial-specific promoter (Tie2-GFP) allowing rapid isolation of aortic endothelium. Three weeks after treatment, endothelial cells were isolated from animals with blood glucose > 350 mg/dl. Aortae from the root to the renal bifurcation were rapidly processed by mincing and proteolytic digestion followed by fluorescent activated cell sorting to yield endothelial cell populations of >95% purity. RNA was isolated from >50,000 endothelial cells and subjected to oligo dT amplification prior to transcriptional analysis on microarrays displaying long oligonucleotides representing 32,000 murine transcripts. Five regulated transcripts were selected for analysis by real-time PCR. Results Within replicate microarray experiments, 19 transcripts were apparently dysregulated by at least 70% within diabetic mice. Up-regulation of glycam1, slc36a2, ces3, adipsin and adiponectin was confirmed by real-time PCR. Conclusion By comprehensively examining cellular gene responses in vivo in a whole animal model of type I diabetes, we have identified novel regulation of key endothelial transcripts that likely contribute to the metabolic and pro-inflammatory responses that accompany diabetes.
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Affiliation(s)
- J Gregory Maresh
- Department of Medicine, University of Hawaii John A, Burns School of Medicine, Honolulu, USA.
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183
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Genome-wide linkage analysis for circulating levels of adipokines and C-reactive protein in the Quebec family study (QFS). J Hum Genet 2008; 53:629. [PMID: 18414778 DOI: 10.1007/s10038-008-0291-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Accepted: 03/24/2008] [Indexed: 01/04/2023]
Abstract
Adipose tissue synthesizes and secretes a wide range of biologically active molecules considered as inflammatory markers whose dysregulation in obesity plays a role in the development of insulin resistance and vascular disorders. Thus, finding genes that influence circulating levels of inflammatory biomarkers may provide insights into the genetic determinants of obesity-related metabolic diseases. We performed linkage analyses for fasting plasma levels of adiponectin, C-reactive protein (CRP), interleukin-6 (IL-6) and tumor-necrosis factor-alpha (TNF-alpha) in 764 subjects enrolled in the Quebec family study (QFS). A maximum of 393 pairs of siblings from 211 nuclear families were available for analyses. A total of 443 markers spanning the 22 autosomal chromosomes with an average inter-marker distance of 6.24 Mb were genotyped. Linkage was tested using both allele-sharing (SIBPAL) and variance component linkage methods (MERLIN). We showed suggestive evidence of linkage for plasma adiponectin levels on chromosome 15q21.1 [D15S659; logarithm of the odds (LOD) score = 2.23], 3q13.33 (D3S3023; LOD = 2.09), 20q13.2 (D20S197; LOD = 1.96) and 14q32.2 (D14S1426; LOD = 1.79). Evidence of linkage (SIBPAL) was also found for CRP on 12p11.23 (P = 0.001) and 12q15 (P = 0.0005) and for IL-6 on 14q12 (P = 0.002). None of these linkages remained significant after adjustment for body mass index. No evidence of linkage was found for TNF-alpha plasma levels. These results suggest that several QTLs can influence plasma levels of adiponectin and CRP, partly via their effects on adiposity.
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Abstract
BACKGROUND A variety of substances, including free fatty acids, leptin, tumor necrosis factor-alpha, acylation-stimulating protein, adiponectin, and resistin, are secreted by adipocytes. They modulate insulin sensitivity and are new therapeutic targets in metabolic syndrome. OBJECTIVE To identify novel adipokines derived from visceral adipose tissues. METHOD We used the PCR-based cDNA subtraction method to screen the genes predominantly expressed in visceral white adipose tissues (WATs) in Otsuka Long-Evans Tokushima fatty (OLETF) rats, an animal model of abdominal obesity and type 2 diabetes. RESULTS/CONCLUSIONS We identified the vaspin gene (Serpina12) which is upregulated in visceral WATs of OLETF rats. Vaspin mRNA was barely detectable at 6 weeks of age and it was abundantly and exclusively expressed in visceral WATs at 30 weeks of age, when OLETF rats reach their peak body weight. However, vaspin mRNA decreased with worsening of diabetes and body weight loss. Vaspin mRNA increased with treatment of thiazolidinediones (pioglitazone). Administration of recombinant vaspin into high-fat high-sucrose chow-induced obese ICR mice improved glucose tolerance and insulin sensitivity. Vaspin may be the compensatory molecule in the pathogenesis of metabolic syndrome and vaspin recombinant protein or vaspin-mimicking agents such as vaspin analogs, antibodies or small molecule agents may be the link to drug discovery and development.
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Affiliation(s)
- Jun Wada
- Okayama University Graduate School of Medicine, Department of Medicine and Clinical Science, 2-5-1 Shikata-cho, Okayama 700-8558, Japan.
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185
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Chiba T, Yamaza H, Komatsu T, Nakayama M, Fujita S, Hayashi H, Higami Y, Shimokawa I. Pituitary growth hormone suppression reduces resistin expression and enhances insulin effectiveness: relationship with caloric restriction. Exp Gerontol 2008; 43:595-600. [PMID: 18430535 DOI: 10.1016/j.exger.2008.03.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2008] [Revised: 02/28/2008] [Accepted: 03/11/2008] [Indexed: 11/16/2022]
Abstract
Caloric restriction (CR) retards various age-dependent disorders, increases lifespan, and improves insulin activity in laboratory animals. Recently, adipocytes were found to act together as an active endocrine organ that produces various hormones called adipocytokines. The peripheral and central activities of these adipocytokines have been suggested to mediate the anti-aging effects of CR. Here, we tested this notion by analyzing the effect of CR and suppression of growth hormone/insulin-like growth factor-I (GH/IGF-I) axis on the expression of resistin, adiponectin, and adipsin genes by rat white adipose tissue (WAT). We found that CR and GH/IGF-I suppression markedly downregulated resistin gene expression. We also found plasma resistin levels correlated positively with pituitary GH mRNA expression levels. Our observations suggest that CR reduces resistin expression and increases insulin effectiveness in a GH/IGF-I-dependent manner. The beneficial effects of CR and GH/IGF-I suppression appear to be mediated, at least in part, by changes in glucose metabolism that result from reductions in plasma resistin levels.
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Affiliation(s)
- Takuya Chiba
- Department of Investigative Pathology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Nagasaki 852-8523, Japan.
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186
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Paglialunga S, Fisette A, Yan Y, Deshaies Y, Brouillette JF, Pekna M, Cianflone K. Acylation-stimulating protein deficiency and altered adipose tissue in alternative complement pathway knockout mice. Am J Physiol Endocrinol Metab 2008; 294:E521-9. [PMID: 18160458 DOI: 10.1152/ajpendo.00590.2007] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Acylation-stimulating protein (C3adesArg/ASP) is an adipokine that acts on its receptor C5L2 to stimulate triglyceride (TG) synthesis in adipose tissue. The present study investigated ASP levels in mouse models of obesity and leanness and the effect of ASP deficiency in C3 knockout (C3KO) mice on adipose tissue morphology. Plasma ASP levels in wild-type (WT) mice correlated positively with plasma nonesterified fatty acids (NEFA) (R = 0.664, P < 0.001) and total cholesterol (R = 0.515, P < 0.001). Plasma ASP was increased by 85% in obese ob/ob leptin-deficient mice and decreased in lean diacylglycerol acyltransferase 1 (DGAT1) KO mice (-54%) and C/EBPalpha(beta/beta) transgenic mice (-70%) compared with WT. Mice lacking alternative complement factor B or adipsin (FBKO or ADKO), required for ASP production, were also ASP deficient. Both FBKO and C3KO mice had delayed postprandial TG and NEFA clearance on low-fat (LF) and high-fat (HF) diets, suggesting that lack of ASP, not C3, drives the metabolic phenotype. Adipocyte size distribution in C3KO mice was polarized (increased number of both small and large cells), with decreased adipsin expression (-33% gonadal HF), DGAT1 expression (-31% to -50%) and DGAT activity (-41%). Overall, a reduction/deficiency in ASP is associated with an antiadipogenic state and ASP may provide a target for controlling fat storage.
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187
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Wen Y, Wang H, MacLaren R, Wu J, Lu H, Cianflone K. Palmitate and oleate induction of acylation stimulating protein resistance in 3T3-L1 adipocytes and preadipocytes. J Cell Biochem 2008; 104:391-401. [DOI: 10.1002/jcb.21631] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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188
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Food Intake Regulation by Central Complement System. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008. [DOI: 10.1007/978-0-387-78952-1_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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189
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C1-Esterase Inhibitor Protects Against Neointima Formation After Arterial Injury in Atherosclerosis-Prone Mice. Circulation 2008; 117:70-8. [DOI: 10.1161/circulationaha.107.715649] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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190
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Pritchard MT, McMullen MR, Edward Medof M, Stavitsky A, Nagy LE. Role of Complement in Ethanol-Induced Liver Injury. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008. [DOI: 10.1007/978-0-387-78952-1_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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191
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MacLaren R, Cui W, Cianflone K. Adipokines and the immune system: an adipocentric view. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 632:1-21. [PMID: 19025110 DOI: 10.1007/978-0-387-78952-1_1] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
There is increasing evidence of close interactions between the adipose and the immune systems. Adipocytes secrete multiple factors, including adipokines such as leptin and adiponectin that have both pro- and anti-inflammatory effects, and influence diseases involving the immune system. Further, adipose tissue also secretes various chemokines and cytokines, derived from either the adipocytes themselves, or the neighbouring cells including both resident and infiltrating macrophages. This close physical and paracrine interaction results in reciprocal actions of adipocytes, preadipocytes and macrophages within the microenvironment of the adipose tissue. Adipose tissue is a source of Acylation Stimulating Protein (ASP)/C3adesArg which interacts with the receptor C5L2 to stimulate triglyceride synthesis and glucose transport. C5L2, present on adipocytes, preadipocytes, macrophages, and numerous other myeloid and non-myeloid cells is also postulated to be a decoy receptor for C5a in immune cells. Several reviews within the past year have recently examined the role of C5L2 in C5a-mediated physiology. The present mini-review is an adipocentric view with emphasis on the role of ASP and C5L2 in lipid metabolism. C5L2 may play a role in mediating, on one hand, ASP stimulation of triglyceride synthesis in adipose, and, on the other hand, a role as mediator of C5a immune function. Both roles remain controversial, and will only be resolved with further studies.
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Affiliation(s)
- Robin MacLaren
- Department of Experimental Medicine, McGill University, Montreal, Canada
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192
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Oktenli C, Ozgurtas T, Dede M, Sanisoglu YS, Yenen MC, Yesilova Z, Kenar L, Kurt YG, Baser I, Smith J, Cianflone K. Metformin decreases circulating acylation-stimulating protein levels in polycystic ovary syndrome. Gynecol Endocrinol 2007; 23:710-5. [PMID: 18075846 DOI: 10.1080/09513590701666571] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
AIM There are no studies that examine the circulating acylation-stimulating protein (ASP) levels in patients with polycystic ovary syndrome (PCOS). The present study was designed to determine the ASP levels in PCOS and to evaluate the effect of metformin on plasma fasting ASP concentrations. METHODS Twenty women with PCOS and 20 healthy controls matched for age and body mass index (BMI) were included in the study. We determined ASP and other biochemical parameters before and after treatment. RESULTS Baseline levels of plasma ASP, complement 3 (C3), waist-to-hip ratio (WHR), homeostasis model assessment-insulin resistance index (HOMA-IR), fasting insulin, triglycerides (TG) and very-low-density lipoprotein cholesterol (VLDL-C) were significantly higher in patients than in controls. After 3 months of metformin treatment, BMI, WHR, ASP, C3, fasting glucose, fasting insulin, HOMA-IR, total cholesterol, TG, VLDL-C and free testosterone decreased significantly, whereas apolipoprotein A-I and high-density lipoprotein cholesterol increased significantly. CONCLUSIONS The major novel information of the present study is that ASP and C3 values are markedly increased in non-obese patients with PCOS, with a decrease evidenced with metformin treatment.
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Affiliation(s)
- Cagatay Oktenli
- Division of Internal Medicine, Gata Haydarpasa Training Hospital, Kadikoy Istanbul, Turkey.
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193
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Cui W, Paglialunga S, Kalant D, Lu H, Roy C, Laplante M, Deshaies Y, Cianflone K. Acylation-stimulating protein/C5L2-neutralizing antibodies alter triglyceride metabolism in vitro and in vivo. Am J Physiol Endocrinol Metab 2007; 293:E1482-91. [PMID: 17711993 DOI: 10.1152/ajpendo.00565.2006] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acylation-stimulating protein (ASP), a lipogenic hormone, stimulates triglyceride (TG) synthesis and glucose transport upon activation of C5L2, a G protein-coupled receptor. ASP-deficient mice have reduced adipose tissue mass due to increased energy expenditure despite increased food intake. The objective of this study was to evaluate the blocking of ASP-C5L2 interaction via neutralizing antibodies (anti-ASP and anti-C5L2-L1 against C5L2 extracellular loop 1). In vitro, anti-ASP and anti-C5L2-L1 blocked ASP binding to C5L2 and efficiently inhibited ASP stimulation of TG synthesis and glucose transport. In vivo, neither anti-ASP nor anti-C5L2-L1 altered body weight, adipose tissue mass, food intake, or hormone levels (insulin, leptin, and adiponectin), but they did induce a significant delay in TG clearance [P < 0.0001, 2-way repeated-measures (RM) ANOVA] and NEFA clearance (P < 0.0001, 2-way RM ANOVA) after a fat load. After treatment with either anti-ASP or anti-C5L2-L1 antibody there was no change in adipose tissue AMPK activity, but neutralizing antibodies decreased perirenal TG mass (-38.4% anti-ASP, -18.8% anti-C5L2, P < 0.01-0.001) and perirenal LPL activity (-75.6% anti-ASP, -72.5% anti-C5L2, P < 0.05). In liver, anti-C5L2-L1 decreased TG mass (-42.8%, P < 0.05), whereas anti-ASP increased AMPK activity (+34.6%, P < 0.001). In the muscle, anti-C5L2-L1 significantly increased TG mass (+128.0%, P < 0.05), LPL activity (+226.1%, P < 0.001), and AMPK activity (+71.1%, P < 0.01). In addition, anti-ASP increased LPL activity (+164.4, P < 0.05) and AMPK activity (+53.9%, P < 0.05) in muscle. ASP/C5L2-neutralizing antibodies effectively block ASP-C5L2 interaction, altering lipid distribution and energy utilization.
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Affiliation(s)
- Wei Cui
- Department of Experimental Medicine, McGill University, Montreal, Canada
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194
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Haas PJ, van Strijp J. Anaphylatoxins: their role in bacterial infection and inflammation. Immunol Res 2007; 37:161-75. [PMID: 17873401 DOI: 10.1007/bf02697367] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 12/16/2022]
Abstract
Activation of the complement system plays a crucial role in the pathogenesis of infection and inflammation. Especially the complement activation products C3a and C5a, known as the anaphylatoxins, are potent proinflammatory mediators. In addition to their evident role in innate immunity, it is clear that the anaphylatoxins also play a role in regulation of adaptive immune responses. The anaphylatoxins play a role in a variety of infectious and inflammatory diseases like sepsis, ischemia-reperfusion injury, immune complex diseases, and hypersensitivity diseases like asthma. In this review we discuss the role of anaphylatoxins in infection and inflammation. Furthermore, we focus on bacterial complement evasion strategies that can provide tools for further research on pathogenesis of infectious diseases and a better understanding of the role of complement and anaphylatoxins in infection and inflammation.
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Affiliation(s)
- Pieter-Jan Haas
- Eijkman-Winkler Center for Experimental Microbiology, University Medical Center Utrecht, HP:G04-614, Utrecht, 3584 CX, The Netherlands.
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195
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Abstract
A identificação da leptina, hormônio secretado pelos adipócitos, cujo efeito sobre o sistema nervoso simpático e a função endócrina confere participação ativa no controle do dispêndio energético, bem como do apetite, acrescentou às funções do tecido adiposo no organismo humano o papel de órgão multifuncional, produtor e secretor de inúmeros peptídeos e proteínas bioativas, denominadas adipocitocinas. Alterações na quantidade de tecido adiposo, como ocorrem na obesidade, afetam a produção da maioria desses fatores secretados pelos adipócitos. Ainda que essas alterações estejam freqüentemente associadas às inúmeras disfunções metabólicas e ao aumento do risco de doenças cardiovasculares, permanece sob investigação o envolvimento do tecido adiposo no desenvolvimento dessas complicações, considerada a sua função endócrina. As concentrações de várias adipocitocinas elevam-se na obesidade e têm sido relacionadas à hipertensão (angiotensinogênio), ao prejuízo da fibrinólise (inibidor do ativador de plasminogênio-1) e à resistência à insulina (proteína estimuladora de acilação, fator de necrose tumoral-alfa, interleucina-6 e resistina). De outro modo, leptina e adiponectina têm efeitos sobre a sensibilidade à insulina. Na obesidade, a resistência insulínica também está relacionada à resistência à leptina e aos teores plasmáticos reduzidos de adiponectina. Leptina e adiponectina ainda exercem efeitos orgânicos adicionais distintos: frente à participação da leptina no controle da ingestão alimentar, a adiponectina apresenta potente ação anti-aterogênica. Algumas drogas utilizadas no controle do diabetes elevam a produção endógena de adiponectina, em roedores e humanos, indicando que o desenvolvimento de novos medicamentos com alvo nas adipocitocinas pode representar uma alternativa terapêutica de prevenção da resistência insulínica e da aterosclerose em indivíduos obesos.
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196
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Johswich K, Klos A. C5L2--an anti-inflammatory molecule or a receptor for acylation stimulating protein (C3a-desArg)? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 598:159-80. [PMID: 17892211 DOI: 10.1007/978-0-387-71767-8_12] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Kay Johswich
- Medical School Hannover, Department of Medical Microbiology, 30625 Hannover, Germany.
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197
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Alipour A, Elte JWF, van Zaanen HCT, Rietveld AP, Cabezas MC. Postprandial inflammation and endothelial dysfuction. Biochem Soc Trans 2007; 35:466-9. [PMID: 17511629 DOI: 10.1042/bst0350466] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Postprandial hyperlipidaemia is a common metabolic disturbance in atherosclerosis. During the postprandial phase, chylomicrons and their remnants can penetrate the intact endothelium and cause foam cell formation. These particles are highly atherogenic after modification. People in the Western world are non-fasting for most of the day, which consequently leads to a continuous challenge of the endothelium by atherogenic lipoproteins and their remnants. Furthermore, atherosclerosis is considered a low-grade chronic inflammatory disease. Many studies have shown that the process of atherogenesis in part starts with the interaction between the activated leucocytes and activated endothelium. Postprandial lipoproteins can activate leucocytes in the blood and up-regulate the expression of leucocyte adhesion molecules on the endothelium, facilitating adhesion and migration of inflammatory cells into the subendothelial space. Another inflammatory process associated with postprandial lipaemia is the activation of the complement system. Its central component C3 has been associated with obesity, coronary sclerosis, the metabolic syndrome and fasting and postprandial TAGs (triacylglycerols). Moreover, chylomicrons are the strongest stimulators of adipocyte C3 production via activation of the alternative complement cascade. A postprandial C3 increment has been shown in healthy subjects and in patients with CAD (coronary artery disease) and with FCHL (familial combined hyperlipidaemia). Postprandial lipaemia has been related to TAG and free fatty acid metabolism. All of these mechanisms provide an alternative explanation for the atherogenicity of the postprandial period.
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Affiliation(s)
- A Alipour
- Department of Internal Medicine, St Franciscus Gasthuis, Center for Diabetes and Vascular Medicine, PO Box 10900, 3004 BA Rotterdam, The Netherlands
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198
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Goralski KB, McCarthy TC, Hanniman EA, Zabel BA, Butcher EC, Parlee SD, Muruganandan S, Sinal CJ. Chemerin, a novel adipokine that regulates adipogenesis and adipocyte metabolism. J Biol Chem 2007; 282:28175-88. [PMID: 17635925 DOI: 10.1074/jbc.m700793200] [Citation(s) in RCA: 599] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Obesity is an alarming primary health problem and is an independent risk factor for type II diabetes, cardiovascular diseases, and hypertension. Although the pathologic mechanisms linking obesity with these co-morbidities are most likely multifactorial, increasing evidence indicates that altered secretion of adipose-derived signaling molecules (adipokines; e.g. adiponectin, leptin, and tumor necrosis factor alpha) and local inflammatory responses are contributing factors. Chemerin (RARRES2 or TIG2) is a recently discovered chemoattractant protein that serves as a ligand for the G protein-coupled receptor CMKLR1 (ChemR23 or DEZ) and has a role in adaptive and innate immunity. Here we show an unexpected, high level expression of chemerin and its cognate receptor CMKLR1 in mouse and human adipocytes. Cultured 3T3-L1 adipocytes secrete chemerin protein, which triggers CMKLR1 signaling in adipocytes and other cell types and stimulates chemotaxis of CMKLR1-expressing cells. Adenoviral small hairpin RNA targeted knockdown of chemerin or CMKLR1 expression impairs differentiation of 3T3-L1 cells into adipocytes, reduces the expression of adipocyte genes involved in glucose and lipid homeostasis, and alters metabolic functions in mature adipocytes. We conclude that chemerin is a novel adipose-derived signaling molecule that regulates adipogenesis and adipocyte metabolism.
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Affiliation(s)
- Kerry B Goralski
- Department of Pharmacology and College of Pharmacy, Dalhousie University, Halifax, Nova Scotia B3H 1X5, Canada
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199
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Qureshi K, Abrams GA. Metabolic liver disease of obesity and role of adipose tissue in the pathogenesis of nonalcoholic fatty liver disease. World J Gastroenterol 2007; 13:3540-53. [PMID: 17659704 PMCID: PMC4146793 DOI: 10.3748/wjg.v13.i26.3540] [Citation(s) in RCA: 186] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is an increasingly recognized cause of liver-related morbidity and mortality. It can develop secondary to numerous causes but a great majority of NAFLD cases occur in patients who are obese or present with other components of metabolic syndrome (hypertension, dyslipidemia, diabetes). This is called primary NAFLD and insulin resistance plays a key role in its pathogenesis. Obesity is characterized by expanded adipose tissue, which is under a state of chronic inflammation. This disturbs the normal storage and endocrine functions of adipose tissue. In obesity, the secretome (adipokines, cytokines, free fatty acids and other lipid moieties) of fatty tissue is amplified, which through its autocrine, paracrine actions in fat tissue and systemic effects especially in the liver leads to an altered metabolic state with insulin resistance (IR). IR leads to hyperglycemia and reactive hyperinsulinemia, which stimulates lipid-accumulating processes and impairs hepatic lipid metabolism. IR enhances free fatty acid delivery to liver from the adipose tissue storage due to uninhibited lipolysis. These changes result in hepatic abnormal fat accumulation, which may initiate the hepatic IR and further aggravate the altered metabolic state of whole body. Hepatic steatosis can also be explained by the fact that there is enhanced dietary fat delivery and physical inactivity. IR and NAFLD are also seen in various lipodystrophic states in contrary to popular belief that these problems only occur due to excessive adiposity in obesity. Hence, altered physiology of adipose tissue is central to development of IR, metabolic syndrome and NAFLD.
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Affiliation(s)
- Kamran Qureshi
- Department of Medicine, University of Alabama at Birmingham, 1918 University Blvd 286 MCLM Birmingham, AL 35294, USA
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200
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MacLaren R, Cui W, Cianflone K. Visfatin expression is hormonally regulated by metabolic and sex hormones in 3T3-L1 pre-adipocytes and adipocytes. Diabetes Obes Metab 2007; 9:490-7. [PMID: 17587391 DOI: 10.1111/j.1463-1326.2006.00625.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
AIM The novel adipokine visfatin has 'insulin-mimicking' effects and is increased in models of diet-induced obesity, but factors that regulate visfatin have not been fully elucidated. METHODS In order to determine visfatin regulation in adipocyte development and metabolism, as well as in pathophysiological conditions related to metabolic syndrome, endogenous visfatin expression was measured in 3T3-L1 pre-adipocytes and adipocytes using real-time reverse transcriptase polymerase chain reaction (real-time RT-PCR). RESULTS A marked increase in visfatin expression was observed during differentiation, with a 2.2-fold increase between preconfluent and 2-day confluent cells even before differentiation was initiated. A further 4.1-fold increase was induced from day 0 to day 9 of differentiation (overall ninefold). Overnight incubation with dexamethasone (10(-8) to 10(-2) M) increased visfatin expression in both pre-adipocytes (1.5- to 3.3-fold, p < 0.05) and adipocytes (1.9-fold, p < 0.01). All other treatments decreased visfatin expression. In pre-adipocytes, visfatin expression decreased by 23% at a concentration of 1 microM insulin, 15% at 1-15 nM T3, 15% at 10 nM-1 microM progesterone, 33-44% at 10 nM-1 microM testosterone, 50% with palmitate and 30% with oleate (p < 0.05 for all). In adipocytes, insulin had a much greater effect, decreasing visfatin by 77% at 100 nM (p < 0.01), whereas oleate and sex hormones did not affect visfatin expression. However, tumor necrosis factor alpha, which had no effect on pre-adipocytes, significantly decreased visfatin in adipocytes by 26% at 10 ng/ml (p < 0.05). Interestingly, the thiazolidinedione (TZD) rosiglitizone also decreased visfatin by 28% at a concentration of 1 microM (p < 0.01). CONCLUSION In summary, while the mechanism of visfatin action remains to be elucidated, the clear effects of multiple hormones on visfatin expression support a physiological role.
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Affiliation(s)
- R MacLaren
- Mike Rosenbloom Laboratory for Cardiovascular Research, McGill University Health Centre, Montreal, Canada
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