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Liu G, Li M, Saeed M, Xu Y, Ren Q, Sun C. αMSH inhibits adipose inflammation via reducing FoxOs transcription and blocking Akt/JNK pathway in mice. Oncotarget 2018; 8:47642-47654. [PMID: 28514752 PMCID: PMC5564594 DOI: 10.18632/oncotarget.17465] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 04/07/2017] [Indexed: 12/21/2022] Open
Abstract
Alpha melanocyte stimulating hormone (αMSH) abates inflammation in multiple tissues, while Forkhead box proteins O (FoxOs) stimulate inflammatory cascade. However, the relationship between αMSH and FoxOs in adipose inflammation remains unclear. In this study, we used LPS-induced inflammation model, attempted to interpret the function of αMSH in inflammation and the interactions with FoxOs. Results indicated that upon inflammatory situation, the secretion of αMSH and the expression of its receptor MC5R were greatly decreased, but FoxOs expressions were elevated. After the treatment with αMSH, LPS-induced adipose inflammation together with FoxOs expressions was significantly reduced. Conversely, when Foxo1, Foxo3a or Foxo4 overexpressed in αMSH treated inflammatory mouse model, all the anti-inflammatory impacts of αMSH were found disappeared. We further studied the mechanisms by which αMSH exerts its anti-inflammatory impacts and how FoxOs reverse αMSH's function. Foxo4 was found as a negative regulator for MC5R transcription in αMSH inhibited inflammation. Moreover, a negative role was found of αMSH in regulating both Akt and JNK signal pathways by observing the enhanced the anti-inflammatory impacts of pathway-specific inhibitors with αMSH treatment. Our findings demonstrate αMSH plays a key role in the prevention of adipose inflammation and inflammatory diseases by down-regulating Akt/JNK signal pathway and negatively interacting with FoxOs, which brings up αMSH as a novel candidate factor in the adipose anti-inflammation process in obesity.
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Affiliation(s)
- Guannv Liu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Meihang Li
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Muhammad Saeed
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Yatao Xu
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Qian Ren
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Chao Sun
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China
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52
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Ahmad R, Al-Roub A, Kochumon S, Akther N, Thomas R, Kumari M, Koshy MS, Tiss A, Hannun YA, Tuomilehto J, Sindhu S, Rosen ED. The Synergy between Palmitate and TNF-α for CCL2 Production Is Dependent on the TRIF/IRF3 Pathway: Implications for Metabolic Inflammation. THE JOURNAL OF IMMUNOLOGY 2018; 200:3599-3611. [PMID: 29632147 DOI: 10.4049/jimmunol.1701552] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 03/16/2018] [Indexed: 12/24/2022]
Abstract
The chemokine CCL2 (also known as MCP-1) is a key regulator of monocyte infiltration into adipose tissue, which plays a central role in the pathophysiology of obesity-associated inflammation and insulin resistance. It remains unclear how CCL2 production is upregulated in obese humans and rodents. Because elevated levels of the free fatty acid (FFA) palmitate and TNF-α have been reported in obesity, we studied whether these agents interact to trigger CCL2 production. Our data show that treatment of THP-1 and primary human monocytic cells with palmitate and TNF-α led to a marked increase in CCL2 production compared with either treatment alone. Mechanistically, we found that cooperative production of CCL2 by palmitate and TNF-α did not require MyD88, but it was attenuated by blocking TLR4 or TRIF. IRF3-deficient cells did not show synergistic CCL2 production in response to palmitate/TNF-α. Moreover, IRF3 activation by polyinosinic-polycytidylic acid augmented TNF-α-induced CCL2 secretion. Interestingly, elevated NF-κB/AP-1 activity resulting from palmitate/TNF-α costimulation was attenuated by TRIF/IRF3 inhibition. Diet-induced C57BL/6 obese mice with high FFAs levels showed a strong correlation between TNF-α and CCL2 in plasma and adipose tissue and, as expected, also showed increased adipose tissue macrophage accumulation compared with lean mice. Similar results were observed in the adipose tissue samples from obese humans. Overall, our findings support a model in which elevated FFAs in obesity create a milieu for TNF-α to trigger CCL2 production via the TLR4/TRIF/IRF3 signaling cascade, representing a potential contribution of FFAs to metabolic inflammation.
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Affiliation(s)
- Rasheed Ahmad
- Immunology Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait;
| | - Areej Al-Roub
- Immunology Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait
| | - Shihab Kochumon
- Immunology Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait
| | - Nadeem Akther
- Immunology Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait
| | - Reeby Thomas
- Immunology Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait
| | - Manju Kumari
- Division of Endocrinology, Beth Israel Deaconess Medical Center, Harvard School of Medicine, Boston, MA 02215
| | - Merin S Koshy
- Immunology Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait
| | - Ali Tiss
- Proteomics Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait; and
| | - Yusuf A Hannun
- Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794
| | - Jaakko Tuomilehto
- Immunology Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait
| | - Sardar Sindhu
- Immunology Unit, Dasman Diabetes Institute, Kuwait City 15462, Kuwait
| | - Evan D Rosen
- Division of Endocrinology, Beth Israel Deaconess Medical Center, Harvard School of Medicine, Boston, MA 02215
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53
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Hall CJ, Sanderson LE, Lawrence LM, Pool B, van der Kroef M, Ashimbayeva E, Britto D, Harper JL, Lieschke GJ, Astin JW, Crosier KE, Dalbeth N, Crosier PS. Blocking fatty acid-fueled mROS production within macrophages alleviates acute gouty inflammation. J Clin Invest 2018; 128:1752-1771. [PMID: 29584621 DOI: 10.1172/jci94584] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 02/07/2018] [Indexed: 12/17/2022] Open
Abstract
Gout is the most common inflammatory arthritis affecting men. Acute gouty inflammation is triggered by monosodium urate (MSU) crystal deposition in and around joints that activates macrophages into a proinflammatory state, resulting in neutrophil recruitment. A complete understanding of how MSU crystals activate macrophages in vivo has been difficult because of limitations of live imaging this process in traditional animal models. By live imaging the macrophage and neutrophil response to MSU crystals within an intact host (larval zebrafish), we reveal that macrophage activation requires mitochondrial ROS (mROS) generated through fatty acid oxidation. This mitochondrial source of ROS contributes to NF-κB-driven production of IL-1β and TNF-α, which promote neutrophil recruitment. We demonstrate the therapeutic utility of this discovery by showing that this mechanism is conserved in human macrophages and, via pharmacologic blockade, that it contributes to neutrophil recruitment in a mouse model of acute gouty inflammation. To our knowledge, this study is the first to uncover an immunometabolic mechanism of macrophage activation that operates during acute gouty inflammation. Targeting this pathway holds promise in the management of gout and, potentially, other macrophage-driven diseases.
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Affiliation(s)
| | | | | | - Bregina Pool
- Department of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | | | | | | | - Jacquie L Harper
- Malaghan Institute for Medical Research, Wellington, New Zealand
| | - Graham J Lieschke
- Australian Regenerative Medicine Institute, Monash University, Victoria, Australia
| | | | | | - Nicola Dalbeth
- Department of Medicine, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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54
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Integrated Immunomodulatory Mechanisms through which Long-Chain n-3 Polyunsaturated Fatty Acids Attenuate Obese Adipose Tissue Dysfunction. Nutrients 2017; 9:nu9121289. [PMID: 29186929 PMCID: PMC5748740 DOI: 10.3390/nu9121289] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 11/14/2017] [Accepted: 11/16/2017] [Indexed: 12/13/2022] Open
Abstract
Obesity is a global health concern with rising prevalence that increases the risk of developing other chronic diseases. A causal link connecting overnutrition, the development of obesity and obesity-associated co-morbidities is visceral adipose tissue (AT) dysfunction, characterized by changes in the cellularity of various immune cell populations, altered production of inflammatory adipokines that sustain a chronic state of low-grade inflammation and, ultimately, dysregulated AT metabolic function. Therefore, dietary intervention strategies aimed to halt the progression of obese AT dysfunction through any of the aforementioned processes represent an important active area of research. In this connection, fish oil-derived dietary long-chain n-3 polyunsaturated fatty acids (PUFA) in the form of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have been demonstrated to attenuate obese AT dysfunction through multiple mechanisms, ultimately affecting AT immune cellularity and function, adipokine production, and metabolic signaling pathways, all of which will be discussed herein.
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55
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Stabler TV, Montell E, Vergés J, Huebner JL, Kraus VB. Chondroitin Sulfate Inhibits Monocyte Chemoattractant Protein-1 Release From 3T3-L1 Adipocytes: A New Treatment Opportunity for Obesity-Related Inflammation? Biomark Insights 2017; 12:1177271917726964. [PMID: 28890654 PMCID: PMC5574472 DOI: 10.1177/1177271917726964] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 07/27/2017] [Indexed: 12/12/2022] Open
Abstract
Monocyte chemoattractant protein-1 (MCP-1) overproduction from inflamed adipose tissue is a major contributor to obesity-related metabolic syndromes. 3T3-L1 embryonic fibroblasts were cultured and differentiated into adipocytes using an established protocol. Adipocytes were treated with lipopolysaccharide (LPS) to induce inflammation and thus MCP-1 release. At the same time, varying concentrations of chondroitin sulfate (CS) were added in a physiologically relevant range (10-200 µg/mL) to determine its impact on MCP-1 release. Chondroitin sulfate, a natural glycosaminoglycan of connective tissue including the cartilage extracellular matrix, was chosen on the basis of our previous studies demonstrating its anti-inflammatory effect on macrophages. Because the main action of MCP-1 is to induce monocyte migration, cultured THP-1 monocytes were used to test whether CS at the highest physiologically relevant concentration could inhibit cell migration induced by human recombinant MCP-1. Chondroitin sulfate (100-200 µg/mL) inhibited MCP-1 release from inflamed adipocytes in a dose-dependent manner (P < .01, 95% confidence interval [CI]: −5.89 to −3.858 at 100 µg/mL and P < .001, 95% CI: −6.028 to −3.996 at 200 µg/mL) but had no effect on MCP-1–driven chemotaxis of THP-1 monocytes. In summary, CS could be expected to reduce macrophage infiltration into adipose tissue by reduction in adipocyte expression and release of MCP-1 and as such might reduce adipose tissue inflammation in response to pro-inflammatory stimuli such as LPS, now increasingly recognized to be relevant in vivo.
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Affiliation(s)
- Thomas V Stabler
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC, USA
| | - Eulàlia Montell
- Pre-Clinical R&D Department, Bioibérica, S.A.U., Barcelona, Spain
| | - Josep Vergés
- Pre-Clinical R&D Department, Bioibérica, S.A.U., Barcelona, Spain
| | - Janet L Huebner
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC, USA
| | - Virginia Byers Kraus
- Duke Molecular Physiology Institute, Duke University School of Medicine, Durham, NC, USA.,Division of Rheumatology and Immunology, Duke University School of Medicine, Durham, NC, USA
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56
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Inflammation Downregulates UCP1 Expression in Brown Adipocytes Potentially via SIRT1 and DBC1 Interaction. Int J Mol Sci 2017; 18:ijms18051006. [PMID: 28481291 PMCID: PMC5454919 DOI: 10.3390/ijms18051006] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 04/26/2017] [Accepted: 05/02/2017] [Indexed: 12/17/2022] Open
Abstract
Brown adipose tissue thermogenesis at the cost of energy is not only important for the development of obesity, but also possesses great promise in anti-obesity treatment. Uncoupling protein 1 (UCP1) expression has been reported to be under control of the intracellular deacetylase SIRT1. Here, we investigated the effect and mechanism of inflammation and sirtuin-1 (SIRT1) activation on the induction of thermogenic genes in immortalized brown adipocytes incubated with LPS or IL1β and mice with elevated inflammatory tone. In vitro stimulation of brown adipocytes with dibutyryl cyclic adenosine monophosthate (dbcAMP) reduced the expression of deleted in breast cancer-1 (Dbc1) (SIRT1 inhibitor) and increased the Ucp1 expression. Silencing of SIRT1 attenuated dbcAMP induction of Ucp1. In contrast, IL1β increased the expression of Dbc1 and greatly reduced the induction of Ucp1. Similarly, in vivo studies revealed decreased expression of Ucp1 in brown adipose tissue (BAT) in mice chronically infused with LPS. Resveratrol, a known SIRT1 activator, partly rescued the Ucp1 downregulation by inflammation in both the cell cultures and mice. Here, we describe how the expression of Ucp1 in BAT is controlled via SIRT1 and is reduced under inflammation and can be rescued by SIRT1 activation by resveratrol. We suggest the reduced UCP1 expression under inflammation is mediated by the increased expression of DBC1, which inhibits SIRT1 activity.
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57
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Nicholas DA, Zhang K, Hung C, Glasgow S, Aruni AW, Unternaehrer J, Payne KJ, Langridge WHR, De Leon M. Palmitic acid is a toll-like receptor 4 ligand that induces human dendritic cell secretion of IL-1β. PLoS One 2017; 12:e0176793. [PMID: 28463985 PMCID: PMC5413048 DOI: 10.1371/journal.pone.0176793] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 04/17/2017] [Indexed: 01/22/2023] Open
Abstract
Palmitic acid (PA) and other saturated fatty acids are known to stimulate pro-inflammatory responses in human immune cells via Toll-like receptor 4 (TLR4). However, the molecular mechanism responsible for fatty acid stimulation of TLR4 remains unknown. Here, we demonstrate that PA functions as a ligand for TLR4 on human monocyte derived dendritic cells (MoDCs). Hydrophobicity protein modeling indicated PA can associate with the hydrophobic binding pocket of TLR4 adaptor protein MD-2. Isothermal titration calorimetry quantified heat absorption that occurred during PA titration into TLR4/MD2, indicating that PA binds to TLR4/MD2. Treatment of human MoDCs with PA resulted in endocytosis of TLR4, further supporting the function of PA as a TLR4 agonist. In addition, PA stimulated DC maturation and activation based on the upregulation of DC costimulatory factors CD86 and CD83. Further experiments showed that PA induced TLR4 dependent secretion of the pro-inflammatory cytokine IL-1β. Lastly, our experimental data show that PA stimulation of NF-κB canonical pathway activation is regulated by TLR4 signaling and that reactive oxygen species may be important in upregulating this pro-inflammatory response. Our experiments demonstrate for the first time that PA activation of TLR4 occurs in response to direct molecular interactions between PA and MD-2. In summary, our findings suggest a likely molecular mechanism for PA induction of pro-inflammatory immune responses in human dendritic cells expressing TLR4.
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Affiliation(s)
- Dequina A. Nicholas
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Kangling Zhang
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Christopher Hung
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Shane Glasgow
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Aruni Wilson Aruni
- Department of Basic Sciences, Division of Microbiology and Molecular Genetics, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Juli Unternaehrer
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Kimberly J. Payne
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Department of Anatomy and Physiology, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - William H. R. Langridge
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Division of Biochemistry, Department of Basic Sciences, Loma Linda University School Medicine, Loma Linda, California, United States of America
| | - Marino De Leon
- Center for Health Disparities and Molecular Medicine, Loma Linda University School of Medicine, Loma Linda, California, United States of America
- Department of Basic Sciences, Division of Physiology, Loma Linda University School Medicine, Loma Linda, California, United States of America
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58
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Wang C, Ha X, Li W, Xu P, Gu Y, Wang T, Wang Y, Xie J, Zhang J. Correlation of TLR4 and KLF7 in Inflammation Induced by Obesity. Inflammation 2017; 40:42-51. [PMID: 27714571 DOI: 10.1007/s10753-016-0450-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Objective Recent studies have revealed a link between toll-like receptors (TLRs), Kruppel-like factors (KLFs), and the adipose tissue inflammation associated with obesity. TLR4 is associated with chronic inflammation in obesity. KLF7 is known to play an important role in the differentiation of adipocytes, but its role in visceral adipose tissue inflammation has not yet been investigated. Thus, the objective of this study was to determine the correlation of TLR4 and KLF7 in inflammation induced by obesity. Methods A total of 32 Wistar male rat subjects were fed in the center for experimental animals of Shihezi University. The rats were divided into normal control (NC) and high-fat diet (HFD) group. Surgical instruments were used to collect rats' visceral adipose tissue samples in the 10th week after HFD feeding. Ninety-five Uygur subjects between 20 and 90 years old were enrolled in the present study. The subjects were divided into two groups: the normal control group (NC, 18.0 kg/m2 ≤ BMI ≤ 23.9 kg/m2, n = 50) and the obesity group (OB, BMI ≥ 28 kg/m2, n = 45), and visceral adipose tissue was collected from the subjects. Anthropometric and clinical parameters were measured using standard procedures; biochemical indices were detected using the glucose oxidase-peroxidase method and a standardized automatic biochemistry analyzer; the plasma levels of inflammatory factors and adipocytokines were measured by enzyme-linked immunosorbent assay (ELISA); the mRNA and protein expression levels of key genes involved in the inflammatory signaling pathway were measured by real-time PCR and Western blot. Results In rats, compared with the NC group, the weight, Lee's index, waist circumference, visceral fat mass, and the plasma level of Glu, TG, FFA, and TNF-α were higher in the HFD group, while the plasma levels of LPT and APN were significantly lower in the HFD group in the 10th week. Furthermore, compared with the NC group, visceral adipose tissue's mRNA expression levels of TLR4, KLF7, and SRC were higher in the HFD group, and KLF7 was significantly positively correlated with LDL, TLR4, SRC, and IL-6 (P < 0.05). Meanwhile, in the Uygur population, the plasma levels of TG, LDL, and TNF-α in the OB group were significantly higher than those in the NC group (P < 0.05). Moreover, compared with the NC group, visceral adipose tissue's mRNA expression levels of TLR4, KLF7, and SRC were significantly higher in the OB group (P < 0.05), and KLF7 was significantly positively correlated with TC, TLR4, MYD88, SRC, and IL-6 (P < 0.05); the protein expression levels of TLR4 and KLF7 were significantly higher than those in the NC group (P < 0.05). Conclusion Higher expression of TLR4 and KLF7 may play a vital role in the process of inflammation induced by obesity in visceral adipose tissue.
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Affiliation(s)
- Cuizhe Wang
- Shihezi University School of Medicine, Shihezi, Xinjiang, 832000, China
| | - Xiaodan Ha
- Shihezi University School of Medicine, Shihezi, Xinjiang, 832000, China
| | - Wei Li
- Shihezi University School of Medicine, Shihezi, Xinjiang, 832000, China.,Shihezi University School of Medicine in the First Affiliated Hospital Clinical Laboratory, Shihezi, Xinjiang, 832000, China
| | - Peng Xu
- Shihezi University School of Medicine, Shihezi, Xinjiang, 832000, China
| | - Yajuan Gu
- Shihezi University School of Medicine, Shihezi, Xinjiang, 832000, China
| | - Tingting Wang
- Shihezi University School of Medicine, Shihezi, Xinjiang, 832000, China
| | - Yan Wang
- Endocrinology Department of Xinjiang Uygur Autonomous Region People's Hospital, Urumqi, Xinjiang, 830001, China
| | - Jianxin Xie
- Shihezi University School of Medicine, Shihezi, Xinjiang, 832000, China.
| | - Jun Zhang
- Shihezi University School of Medicine, Shihezi, Xinjiang, 832000, China.
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59
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Rahman MS, Murphy AJ, Woollard KJ. Effects of dyslipidaemia on monocyte production and function in cardiovascular disease. Nat Rev Cardiol 2017; 14:387-400. [PMID: 28300081 DOI: 10.1038/nrcardio.2017.34] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Monocytes are heterogeneous effector cells involved in the maintenance and restoration of tissue integrity. Monocytes and macrophages are involved in cardiovascular disease progression, and are associated with the development of unstable atherosclerotic plaques. Hyperlipidaemia can accelerate cardiovascular disease progression. However, monocyte responses to hyperlipidaemia are poorly understood. In the past decade, accumulating data describe the relationship between the dynamic blood lipid environment and the heterogeneous circulating monocyte pool, which might have profound consequences for cardiovascular disease. In this Review, we explore the updated view of monocytes in cardiovascular disease and their relationship with macrophages in promoting the homeostatic and inflammatory responses related to atherosclerosis. We describe the different definitions of dyslipidaemia, highlight current theories on the ontogeny of monocyte heterogeneity, discuss how dyslipidaemia might alter monocyte production, and explore the mechanistic interface linking dyslipidaemia with monocyte effector functions, such as migration and the inflammatory response. Finally, we discuss the role of dietary and endogenous lipid species in mediating dyslipidaemic responses, and the role of these lipids in promoting the risk of cardiovascular disease through modulation of monocyte behaviour.
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Affiliation(s)
- Mohammed Shamim Rahman
- Renal &Vascular Inflammation Section, Division of Immunology and Inflammation, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Andrew J Murphy
- Haematopoiesis and Leukocyte Biology Lab, Baker IDI Heart &Diabetes Research Institute, 75 Commercial Road, Melbourne, Victoria 3004, Australia.,Department of Immunology, Monash University, 89 Commercial Road, Melbourne, Victoria 3004, Australia
| | - Kevin J Woollard
- Renal &Vascular Inflammation Section, Division of Immunology and Inflammation, Imperial College London, Du Cane Road, London W12 0NN, UK
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60
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Mahesh M, Bharathi M, Raja Gopal Reddy M, Pappu P, Putcha UK, Vajreswari A, Jeyakumar SM. Carrot juice ingestion attenuates high fructose-induced circulatory pro-inflammatory mediators in weanling Wistar rats. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2017; 97:1582-1591. [PMID: 27417700 DOI: 10.1002/jsfa.7906] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 04/30/2016] [Accepted: 07/11/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Adipose tissue, an endocrine organ, plays a vital role not only in energy homeostasis, but also in the development and/or progression of various metabolic diseases, such as insulin resistance, type 2 diabetes and non-alcoholic fatty liver disease (NAFLD), via several factors and mechanisms, including inflammation. This study tested, whether carrot juice administration affected the adipose tissue development and its inflammatory status in a high fructose diet-induced rat model. For this purpose, male weanling Wistar rats were divided into four groups and fed either control or high fructose diet of AIN-93G composition with or without carrot juice ingestion for an 8 week period. RESULTS Administration of carrot juice did not affect the adiposity and cell size of visceral fat depot; retroperitoneal white adipose tissue (RPWAT), which was corroborated with unaltered expression of genes involved in adipogenic and lipogenic pathways. However, it significantly reduced the high fructose diet-induced elevation of plasma free fatty acid (FFA) (P ≤ 0.05), macrophage chemoattractant protein 1 (MCP1) (P ≤ 0.01) and high sensitive C-reactive protein (hsCRP) (P ≤ 0.05) levels. CONCLUSION Carrot juice administration attenuated the high fructose diet-induced elevation of levels of circulatory FFA and pro-inflammatory mediators; MCP1 and hsCRP without affecting the adiposity and cell size of visceral fat depot; RPWAT. © 2016 Society of Chemical Industry.
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Affiliation(s)
- Malleswarapu Mahesh
- Lipid Biochemistry Division, National Institute of Nutrition, Jamai Osmania, Hyderabad, 500007, India
| | - Munugala Bharathi
- Lipid Biochemistry Division, National Institute of Nutrition, Jamai Osmania, Hyderabad, 500007, India
| | - Mooli Raja Gopal Reddy
- Lipid Biochemistry Division, National Institute of Nutrition, Jamai Osmania, Hyderabad, 500007, India
| | - Pranati Pappu
- Lipid Biochemistry Division, National Institute of Nutrition, Jamai Osmania, Hyderabad, 500007, India
| | - Uday Kumar Putcha
- Pathology Division, National Institute of Nutrition, Jamai Osmania, Hyderabad, 500007, India
| | | | - Shanmugam M Jeyakumar
- Lipid Biochemistry Division, National Institute of Nutrition, Jamai Osmania, Hyderabad, 500007, India
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61
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Reichardt F, Chassaing B, Nezami BG, Li G, Tabatabavakili S, Mwangi S, Uppal K, Liang B, Vijay-Kumar M, Jones D, Gewirtz AT, Srinivasan S. Western diet induces colonic nitrergic myenteric neuropathy and dysmotility in mice via saturated fatty acid- and lipopolysaccharide-induced TLR4 signalling. J Physiol 2017; 595:1831-1846. [PMID: 28000223 PMCID: PMC5330876 DOI: 10.1113/jp273269] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 12/01/2016] [Indexed: 01/01/2023] Open
Abstract
KEY POINTS A high-fat diet (60% kcal from fat) is associated with motility disorders inducing constipation and loss of nitrergic myenteric neurons in the proximal colon. Gut microbiota dysbiosis, which occurs in response to HFD, contributes to endotoxaemia. High levels of lipopolysaccharide lead to apoptosis in cultured myenteric neurons that express Toll-like receptor 4 (TLR4). Consumption of a Western diet (WD) (35% kcal from fat) for 6 weeks leads to gut microbiota dysbiosis associated with altered bacterial metabolites and increased levels of plasma free fatty acids. These disorders precede the nitrergic myenteric cell loss observed in the proximal colon. Mice lacking TLR4 did not exhibit WD-induced myenteric cell loss and dysmotility. Lipopolysaccharide-induced in vitro enteric neurodegeneration requires the presence of palmitate and may be a result of enhanced NO production. The present study highlights the critical role of plasma saturated free fatty acids that are abundant in the WD with respect to driving enteric neuropathy and colonic dysmotility. ABSTRACT The consumption of a high-fat diet (HFD) is associated with myenteric neurodegeneration, which in turn is associated with delayed colonic transit and constipation. We examined the hypothesis that an inherent increase in plasma free fatty acids (FFA) in the HFD together with an HFD-induced alteration in gut microbiota contributes to the pathophysiology of these disorders. C57BL/6 mice were fed a Western diet (WD) (35% kcal from fat enriched in palmitate) or a purified regular diet (16.9% kcal from fat) for 3, 6, 9 and 12 weeks. Gut microbiota dysbiosis was investigated by fecal lipopolysaccharide (LPS) measurement and metabolomics (linear trap quadrupole-Fourier transform mass spectrometer) analysis. Plasma FFA and LPS levels were assessed, in addition to colonic and ileal nitrergic myenteric neuron quantifications and motility. Compared to regular diet-fed control mice, WD-fed mice gained significantly more weight without blood glucose alteration. Dysbiosis was exhibited after 6 weeks of feeding, as reflected by increased fecal LPS and bacterial metabolites and concomitant higher plasma FFA. The numbers of nitrergic myenteric neurons were reduced in the proximal colon after 9 and 12 weeks of WD and this was also associated with delayed colonic transit. WD-fed Toll-like receptor 4 (TLR4)-/- mice did not exhibit myenteric cell loss or dysmotility. Finally, LPS (0.5-2 ng·ml-1 ) and palmitate (20 and 30 μm) acted synergistically to induce neuronal cell death in vitro, which was prevented by the nitric oxide synthase inhibitor NG-nitro-l-arginine methyl ester. In conclusion, WD-feeding results in increased levels of FFA and microbiota that, even in absence of hyperglycaemia or overt endotoxaemia, synergistically induce TLR4-mediated neurodegeneration and dysmotility.
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Affiliation(s)
- François Reichardt
- Department of Digestive Diseases, Emory University School of Medicine, Atlanta & Atlanta VA Medical Center, Decatur, GA, USA
| | - Benoit Chassaing
- Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences, Georgia State University, GA, USA
| | - Behtash Ghazi Nezami
- Department of Digestive Diseases, Emory University School of Medicine, Atlanta & Atlanta VA Medical Center, Decatur, GA, USA
| | - Ge Li
- Department of Digestive Diseases, Emory University School of Medicine, Atlanta & Atlanta VA Medical Center, Decatur, GA, USA
| | - Sahar Tabatabavakili
- Department of Digestive Diseases, Emory University School of Medicine, Atlanta & Atlanta VA Medical Center, Decatur, GA, USA
| | - Simon Mwangi
- Department of Digestive Diseases, Emory University School of Medicine, Atlanta & Atlanta VA Medical Center, Decatur, GA, USA
| | - Karan Uppal
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University, GA, USA
| | - Bill Liang
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University, GA, USA
| | - Matam Vijay-Kumar
- Department of Nutritional Sciences & Medicine, Pennsylvania State University, University Park, PA, USA
| | - Dean Jones
- Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Emory University, GA, USA
| | - Andrew T Gewirtz
- Center for Inflammation, Immunity & Infection, Institute for Biomedical Sciences, Georgia State University, GA, USA
| | - Shanthi Srinivasan
- Department of Digestive Diseases, Emory University School of Medicine, Atlanta & Atlanta VA Medical Center, Decatur, GA, USA
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The effects of fat-induced obesity on bone metabolism in rats. Obes Res Clin Pract 2017; 11:454-463. [PMID: 28065384 DOI: 10.1016/j.orcp.2016.12.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 10/17/2016] [Accepted: 12/02/2016] [Indexed: 01/09/2023]
Abstract
OBJECTIVE The aim of the current study was to investigate the effects of obesity, induced via a high-fat diet, on bone metabolism in rats. METHODS Two hundred healthy Wistar male rats aged 4 weeks were fed a standard diet and a high-fat diet. At specific time points (week 0, 4, 6, 8, and 10), plasma was collected to determine the levels of glucose and lipid metabolism. Additionally, enzyme-linked immunoassays were performed to determine the plasma levels of adipocyte and bone metabolism factors. Micro-CT imaging was used to determine the parameters of bone metabolism. At 10th week, immunohistochemistry evaluation of femoral bone samples was performed to determine the expression of adipocyte factors. RESULT Receptor activator of nuclear factor kB ligand (RANKL) was positively correlated with levels of triglyceride (TG), free fatty acids (FFA), and tumor necrosis factor alpha (TNF-α) (P<0.05), while receptor activator of the NF-κB (RANK) showed a positive correlation with TG, FFA, TNF-α and leptin (LPT) (P<0.05). CT imaging demonstrated that bone mineral density and trabecular thickness were elevated compared to controls before 6 weeks, but these values were found to be lower in rats fed a high fat diet in the following weeks (P<0.05). Immunohistochemistry showed that the expression of TNF-α, Interleukin- 6 (IL-6) and peroxisome proliferator activated receptor-γ (PPAR-γ) were increased and the expression of adiponectin (APN) were diminished in rats fed a high-fat diet compared to controls at 10 weeks (P<0.05). CONCLUSION With obesity intensifies, the release of FFA cause inflammation factor increase, resulting in bone parameters decreased.
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Correlation of A2bAR and KLF4/KLF15 with Obesity-Dyslipidemia Induced Inflammation in Uygur Population. Mediators Inflamm 2016; 2016:7015620. [PMID: 27199507 PMCID: PMC4856914 DOI: 10.1155/2016/7015620] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 03/03/2016] [Accepted: 03/31/2016] [Indexed: 12/23/2022] Open
Abstract
In this paper, the researchers collected visceral adipose tissue from the Uygur population, which were divided into two groups: the normal control group (NC, n = 50, 18.0 kg/m(2) ≤ BMI ≤ 23.9 kg/m(2)) and the obese group (OB, n = 45, BMI ≥ 28 kg/m(2)), and then use real-time PCR to detect the mRNA expression level of key genes involved in inflammation signaling pathway. The findings suggest that, in obese status, the lower expression level of A2bAR, KLF4, and KLF15 of visceral adipose tissue may correlate with obese-dyslipidemia induced inflammation in Uygur population.
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Zacherl JR, Tourkova I, St Croix CM, Robinson LJ, Peck Palmer OM, Mihalik SJ, Blair HC. Elaidate, an 18-carbon trans-monoenoic fatty acid, but not physiological fatty acids increases intracellular Zn(2+) in human macrophages. J Cell Biochem 2016; 116:524-32. [PMID: 25358453 DOI: 10.1002/jcb.25002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 10/24/2014] [Indexed: 11/07/2022]
Abstract
Artificial trans fatty acids promote atherosclerosis by blocking macrophage clearance of cell debris. Classical fatty-acid response mechanisms include TLR4-NF-κB activation, and Erk1/2 phosphorylation, but these may not indicate long-term mechanisms. Indeed, nuclear NF-κB was increased by 60 min treatment by 30 μM of the 18 carbon trans unsaturated fatty acid elaidic acid (elaidate), the physiological cis-unsaturated fatty acid oleic acid (oleate), and the 18 or 16 carbon saturated fatty acids stearic and palmitic acid (stearate or palmitate). However, except for stearate, effects on related pathways were minimal at 44 h. To determine longer term effects of trans fatty acids, we compared mRNA expression profiles of (trans) elaidate to (cis) oleate, 30 μM, at 44 h in human macrophages. We found that elaidate changed Zn(2+) -homeostasis gene mRNAs markedly. This might be important because Zn(2+) is a major regulator of macrophage activity. Messenger RNAs of seven Zn(2+) -binding metallothioneins decreased 2-4-fold; the zinc importer SLC39A10 increased twofold, in elaidate relative to oleate-treated cells. Results were followed by quantitative PCR comparing cis, trans, and saturated fatty acid effects on Zn(2+) -homeostasis gene mRNAs. This confirmed that elaidate uniquely decreased metallothionein expression and increased SLC39A10 at 44 h. Further, intracellular Zn(2+) was measured using N-(carboxymethyl)-N-[2-[2-[2(carboxymethyl) amino]-5-(2,7,-difluoro-6-hydroxy-3-oxo-3H-xanthen-9-yl)-phenoxy]-ethoxy]-4-methoxyphenyl]glycine, acetoxymethyl ester (FluoZin-3-AM). This showed that, at 44 h, only cells treated with elaidate had increased Zn(2+) . The durable effect of elaidate on Zn(2+) activation is a novel and specific effect of trans fatty acids on peripheral macrophage metabolism.
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Affiliation(s)
- Janelle R Zacherl
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, 15261
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Sultana A, Cochran BJ, Tabet F, Patel M, Torres LC, Barter PJ, Rye KA. Inhibition of inflammatory signaling pathways in 3T3-L1 adipocytes by apolipoprotein A-I. FASEB J 2016; 30:2324-35. [PMID: 26965683 DOI: 10.1096/fj.201500026r] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 02/22/2016] [Indexed: 01/04/2023]
Abstract
Activation of inflammatory signaling pathways links obesity with metabolic disorders. TLR4-mediated activation of MAPKs and NF-κB are 2 such pathways implicated in obesity-induced inflammation. Apolipoprotein A-I (apoA-I) exerts anti-inflammatory effects on adipocytes by effluxing cholesterol from the cells via the ATP binding cassette transporter A1 (ABCA1). It is not known if these effects involve inhibition of inflammatory signaling pathways by apoA-I. This study asks if apoA-I inhibits activation of MAPKs and NF-κB in mouse 3T3-L1 adipocytes and whether this inhibition is ABCA1 dependent. Incubation of differentiated 3T3-L1 adipocytes with apoA-I decreased cell surface expression of TLR4 by 16 ± 2% and synthesis of the TLR4 adaptor protein, myeloid differentiation primary response 88, by 24 ± 4% in an ABCA1-dependent manner. ApoA-I also inhibited downstream activation of MAPKs, such as ERK, p38MAPK, and JNK, as well as expression of proinflammatory adipokines in bacterial LPS-stimulated 3T3-L1 adipocytes in an ABCA1-dependent manner. ApoA-I, by contrast, suppressed nuclear localization of the p65 subunit of NF-κB by 30 ± 3% in LPS-stimulated 3T3-L1 adipocytes in an ABCA1-independent manner. In conclusion, apoA-I inhibits TLR4-mediated inflammatory signaling pathways in adipocytes by preventing MAPK and NF-κB activation.-Sultana, A., Cochran, B. J., Tabet, F., Patel, M., Cuesta Torres, L., Barter, P. J., Rye, K.-A. Inhibition of inflammatory signaling pathways in 3T3-L1 adipocytes by apolipoprotein A-I.
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Affiliation(s)
- Afroza Sultana
- Lipid Research Group, School of Medical Sciences, Faculty of Medicine, University of New South Wales Australia, Sydney, New South Wales, Australia; and
| | - Blake J Cochran
- Lipid Research Group, School of Medical Sciences, Faculty of Medicine, University of New South Wales Australia, Sydney, New South Wales, Australia; and
| | - Fatiha Tabet
- Lipid Research Group, School of Medical Sciences, Faculty of Medicine, University of New South Wales Australia, Sydney, New South Wales, Australia; and
| | - Mili Patel
- Lipid Research Group, School of Medical Sciences, Faculty of Medicine, University of New South Wales Australia, Sydney, New South Wales, Australia; and
| | - Luisa Cuesta Torres
- Lipid Research Group, School of Medical Sciences, Faculty of Medicine, University of New South Wales Australia, Sydney, New South Wales, Australia; and
| | - Philip J Barter
- Lipid Research Group, School of Medical Sciences, Faculty of Medicine, University of New South Wales Australia, Sydney, New South Wales, Australia; and Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Kerry-Anne Rye
- Lipid Research Group, School of Medical Sciences, Faculty of Medicine, University of New South Wales Australia, Sydney, New South Wales, Australia; and Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
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Nature and nurture in atherosclerosis: The roles of acylcarnitine and cell membrane-fatty acid intermediates. Vascul Pharmacol 2015; 78:17-23. [PMID: 26133667 DOI: 10.1016/j.vph.2015.06.012] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 06/26/2015] [Accepted: 06/27/2015] [Indexed: 12/22/2022]
Abstract
Macrophages recycle components of dead cells, including cell membranes. When quantities of lipids from cell membranes of dead cells exceed processing capacity, phospholipid and cholesterol debris accumulate as atheromas. Plasma lipid profiles, particularly HDL and LDL cholesterol, are important tools to monitor atherosclerosis risk. Membrane lipids are exported, as triglycerides or phospholipids, or as cholesterol or cholesterol esters, via lipoproteins for disposal, for re-use in cell membranes, or for fat storage. Alternative assays evaluate other aspects of lipid pathology. A key process underlying atherosclerosis is backup of macrophage fatty acid catabolism. This can be quantified by accumulation of acylcarnitine intermediates in extracellular fluid, a direct assay of adequacy of β-oxidation to deal with membrane fatty acid recycling. Further, membranes of somatic cells, such as red blood cells (RBC), incorporate fatty acids that reflect dietary intake. Changes in RBC lipid composition occur within days of ingesting modified fats. Since diets with high saturated fat content or artificial trans-fatty acids promote atherosclerosis, RBC lipid content shifts occur with atherosclerosis, and can show cellular adaptation to pathologically stiff membranes by increased long-chain doubly unsaturated fatty acid production. Additional metabolic changes with atherosclerosis of potential utility include inflammatory cytokine production, modified macrophage signaling pathways, and altered lipid-handling enzymes. Even after atherosclerotic lesions appear, approaches to minimize macrophage overload by reducing rate of fat metabolism are promising. These include preventive measures, and drugs including statins and the newer PCSK9 inhibitors. New cell-based biochemical and cytokine assays provide data to prevent or monitor atherosclerosis progression.
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Alaskan seaweeds lower inflammation in RAW 264.7 macrophages and decrease lipid accumulation in 3T3-L1 adipocytes. J Funct Foods 2015. [DOI: 10.1016/j.jff.2015.03.049] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Bao S, Cao Y, Zhou H, Sun X, Shan Z, Teng W. Epigallocatechin gallate (EGCG) suppresses lipopolysaccharide-induced Toll-like receptor 4 (TLR4) activity via 67 kDa laminin receptor (67LR) in 3T3-L1 adipocytes. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:2811-2819. [PMID: 25732404 DOI: 10.1021/jf505531w] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Obesity-related insulin resistance is associated with chronic systemic low-grade inflammation, and toll-like receptor 4 (TLR4) regulates inflammation. We investigated the pathways involved in epigallocatechin gallate (EGCG) modulation of insulin and TLR4 signaling in adipocytes. Inflammation was induced in adipocytes by lipopolysaccharide (LPS). An antibody against the 67 kDa laminin receptor (67LR, to which EGCG exclusively binds) was used to examine the effect of EGCG on TLR4 signaling, and a TLR4/MD-2 antibody was used to inhibit TLR4 activity and to determine the insulin sensitivity of differentiated 3T3-L1 adipocytes. We found that EGCG dose-dependently inhibited LPS stimulation of adipocyte inflammation by reducing inflammatory mediator and cytokine levels (IKKβ, p-NF-κB, TNF-α, and IL-6). Pretreatment with the 67LR antibody prevented EGCG inhibition of inflammatory cytokines, decreased glucose transporter isoform 4 (GLUT4) expression, and inhibited insulin-stimulated glucose uptake. TLR4 inhibition attenuated inflammatory cytokine levels and increased glucose uptake by reversing GLUT4 levels. These data suggest that EGCG suppresses TLR4 signaling in LPS-stimulated adipocytes via 67LR and attenuates insulin-stimulated glucose uptake associated with decreased GLUT4 expression.
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Affiliation(s)
- Suqing Bao
- Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning 110001, People's Republic of China
| | - Yanli Cao
- Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning 110001, People's Republic of China
| | - Haicheng Zhou
- Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning 110001, People's Republic of China
| | - Xin Sun
- Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning 110001, People's Republic of China
| | - Zhongyan Shan
- Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning 110001, People's Republic of China
| | - Weiping Teng
- Department of Endocrinology and Metabolism, Institute of Endocrinology, Liaoning Provincial Key Laboratory of Endocrine Diseases, The First Affiliated Hospital of China Medical University, No. 155, North Nanjing Street, Heping District, Shenyang, Liaoning 110001, People's Republic of China
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Da Silva MS, Rudkowska I. Dairy nutrients and their effect on inflammatory profile in molecular studies. Mol Nutr Food Res 2015; 59:1249-63. [DOI: 10.1002/mnfr.201400569] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 12/23/2014] [Accepted: 12/29/2014] [Indexed: 12/17/2022]
Affiliation(s)
- Marine S. Da Silva
- Department of Endocrinology and Nephrology; CHU de Québec Research Center; Quebec QC Canada
| | - Iwona Rudkowska
- Department of Endocrinology and Nephrology; CHU de Québec Research Center; Quebec QC Canada
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Ma W, Lu S, Sun T, Wang X, Ma Y, Zhang X, Zhao R, Wang Y. Twist 1 regulates the expression of PPARγ during hormone-induced 3T3-L1 preadipocyte differentiation: a possible role in obesity and associated diseases. Lipids Health Dis 2014; 13:132. [PMID: 25128964 PMCID: PMC4150960 DOI: 10.1186/1476-511x-13-132] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 08/12/2014] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Twist 1 is highly expressed in adipose tissue and has been associated with obesity and related disorders. However, the molecular function of Twist 1 in adipose tissue is unclear. Twist 1 has been implicated in cell lineage determination and differentiation. Therefore, we investigated both the role of Twist 1 in adipocyte precursor mobilization and the relationship of Twist 1 with other molecular determinants of adipocyte differentiation. METHODS We examined Twist 1 mRNA and protein expression in subcutaneous adipose tissues from diet-induced obese C57/BL6 mice and Wistar rats and in obese patients undergoing liposuction or adipose transplant surgeries. Twist 1 expression was measured on days 0, 2, 4, 8, and 12 of 3T3-L1 differentiation in vitro. The role of Twist 1 in adipogenesis was explored using retroviral interference of Twist 1 expression. Adipokine secretion was evaluated using a RayBio® Biotin Label-based Adipokine Array. RESULTS Twist 1 mRNA and protein levels were reduced in diet-induced obese mice and rats and in obese humans. Twist 1 was upregulated during 3T3-L1 preadipocyte differentiation in vitro, beginning from the fourth day of differentiation induction. Retroviral interference of Twist 1 expression did not significantly impair lipid formation; however, retroviral interference induced PPARγ mRNA and protein expression on day 4 of differentiation induction. Adipokine array analyses revealed increased secretion of CXCR4 (19.55-fold), VEGFR1 (92.13-fold), L-21 R (63.55-fold), and IL-12 R beta 1 (59.66-fold) and decreased secretion of VEGFR3 (0.01-fold), TSLP R (0.071-fold), MIP-1 gamma (0.069-fold), TNF RI/TNFRSF1A (0.09-fold), and MFG-E8 (0.06-fold). CONCLUSIONS Twist 1 is a regulator of adipocyte gene expression although it is not likely to regulate differentiation. We identified PPARγ as a potential target of Twist 1 and found variation in the secretion of multiple adipokines, which might indicate a prospective mechanism linking Twist 1 expression with obesity or associated diseases.
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Affiliation(s)
| | | | | | | | | | | | | | - Yunshan Wang
- Medical Research & Laboratory Diagnostic Center, Jinan Center Hospital Affiliated to Shandong University, Jinan, Shandong 250013, P,R, China.
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