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Trans-10, cis-12 conjugated linoleic acid- and caloric restriction-mediated upregulation of CNDP2 expression in white adipose tissue in rodents, with implications in feeding and obesity. J Nutr Biochem 2023; 114:109269. [PMID: 36641073 DOI: 10.1016/j.jnutbio.2023.109269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 10/27/2022] [Accepted: 01/05/2023] [Indexed: 01/13/2023]
Abstract
Certain dietary supplements such as trans-10, cis-12 conjugated linoleic acid (t10-c12 CLA), and diets including caloric-restricted diets can promote weight loss in certain animal models and humans. A very recent study showed that exercise induces the biosynthesis of N-lactoyl-phenylalanine (Lac-Phe), a circulating signaling metabolite that suppresses feeding and obesity selectively in mice fed with a high-fat diet, and that cytosolic nonspecific dipeptidase 2 (CNDP2) catalyzes the synthesis of Lac-Phe from lactate (Lac) and phenylalanine (Phe). In this in silico study, we found that two anti-obesity strategies, namely treatment with t10-c12 CLA and caloric restriction, increase CNDP2 expression in adipose tissue in mice and rats, respectively. We showed that the effect of t10-c12 CLA on CNDP2 expression might be isomer-specific. We hypothesized that these t10-c12 CLA treatment- or caloric-restricted diet-mediated increases in CNDP2 expression might contribute to their anti-obesity effects, possibly due to increased Lac-Phe levels and ultimately due to Lac-Phe-mediated decreases in daily food consumption, reduced body weight and fat mass. A better understanding of the regulation of CNDP2 expression in diverse tissues in mammals might be of high importance in the treatment of obesity, considering its role in the synthesis of Lac-Phe, a metabolite that decreases body weight and fat mass selectively in mice fed with a high-fat diet. Further research is needed to find out how these two strategies lead to the upregulation of CNDP2 expression and whether this increased expression of CNDP2 might translate to reduced body weight and fat mass through higher Lac-Phe levels.
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Zhao Z, Wang C, Jia J, Wang Z, Li L, Deng X, Cai Z, Yang L, Wang D, Ma S, Zhao L, Tu Z, Yuan G. Regulatory network of metformin on adipogenesis determined by combining high-throughput sequencing and GEO database. Adipocyte 2022; 11:56-68. [PMID: 34974794 PMCID: PMC8741290 DOI: 10.1080/21623945.2021.2013417] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Adipose differentiation and excessive lipid accumulation are the important characteristics of obesity. Metformin, as a classic hypoglycaemic drug, has been proved to reduce body weight in type 2 diabetes, the specific mechanism has not been completely clear. A few studies have explored its effect on adipogenesis in vitro, but the existing experimental results are ambiguous. 3T3-L1 preadipocytes were used to explore the effects of metformin on the morphological and physiological changes of lipid droplets during adipogenesis. A high throughput sequencing was used to examine the effects of metformin on the transcriptome of adipogenesis. Considering the inevitable errors among independent experiments, we performed integrated bioinformatics analysis to identify important genes involved in adipogenesis and reveal potential molecular mechanisms. During the process of adipogenesis, metformin visibly relieved the morphological and functional changes. In addition, metformin reverses the expression pattern of genes related to adipogenesis at the transcriptome level. Combining with integrated bioinformatics analyses to further identify the potential targeted genes regulated by metformin during adipogenesis. The present study identified novel changes in the transcriptome of metformin in the process of adipogenesis that might shed light on the underlying mechanism by which metformin impedes the progression of obesity.
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Affiliation(s)
- Zhicong Zhao
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Chenxi Wang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Jue Jia
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Zhaoxiang Wang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Lian Li
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Xia Deng
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Zhensheng Cai
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Ling Yang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Dong Wang
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Suxian Ma
- Department of Endocrinology, Suzhou Municipal Hospital, Suzhou, Jiangsu, China
| | - Li Zhao
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
| | - Zhigang Tu
- School of Life Sciences, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Guoyue Yuan
- Department of Endocrinology, Affiliated Hospital of Jiangsu University, Zhenjiang, Jiangsu, China
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Quantitative Profiling of Oxylipin Reveals the Mechanism of Pien-Tze-Huang on Alcoholic Liver Disease. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2021; 2021:9931542. [PMID: 34158817 PMCID: PMC8187045 DOI: 10.1155/2021/9931542] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/30/2021] [Accepted: 05/06/2021] [Indexed: 12/13/2022]
Abstract
Alcoholic liver disease (ALD) is a liver disease caused by long-term alcohol consumption. ROS-mediated oxidative stress is the leading cause of ALD. Pien-Tze-Huang (PZH), a traditional formula, is famous in China. This study was designed to evaluate the effects and explore the potential mechanisms of PZH in ALD. Forty mice were randomly divided into five groups: control group (normal diet + vehicle), model group (ethanol diet + vehicle), PZH-L group (ethanol diet + PZH (0.125 g/kg)), PZH-M group (ethanol diet + PZH (0.25 g/kg)), and PZH-H group (ethanol diet + PZH (0.5 g/kg)). The mice were sacrificed, and their liver and blood samples were preserved. Liver steatosis, triglyceride (TG), total cholesterol, serum alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels were assayed. Malondialdehyde (MDA), glutathione peroxidase (GSH-PX), and total superoxide dismutase were identified using commercial kits. Oxylipins were profiled, and the data were analyzed. The AMPK/ACC/CPT1A pathway was identified using real-time polymerase chain reaction and western blotting. The PZH-H intervention significantly alleviated hepatic steatosis and injury and reduced the levels of liver TG and serum ALT and AST. In addition, MDA levels were markedly reduced, and GSH-PX activity significantly increased after PZH-H intervention. Finally, PZH-H increased the levels of 17-HETE, 15-HEPE, 9-HOTrE, 13-HOTrE, and 5,6-dihydroxy-8Z,11Z,14Z,17Z-eicosatetraenoic acid, and reduced PGE2 levels. PZH-H intervention also promoted the phosphorylation of AMPK and ACC, and the expression of CPT1A. In conclusion, PZH reduced oxidative stress and alleviated hepatic steatosis and injury. The mechanism was correlated with the oxylipin metabolites/AMPK/ACC/CPT1A axis.
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4
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Ahmed M, Min DS, Kim DR. Curated gene expression dataset of differentiating 3T3-L1 adipocytes under pharmacological and genetic perturbations. Adipocyte 2020; 9:600-608. [PMID: 33016192 PMCID: PMC7553567 DOI: 10.1080/21623945.2020.1829852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The 3T3-L1 cell line is used as an adipocyte differentiation model for the analysis of genes specifically expressed during the differentiation course. This cell model has several applications in obesity and insulin resistance research. We built a data resource to model gene expression of differentiating and mature adipocytes in response to several drugs and gene manipulations. We surveyed the literature survey for microarray datasets of differentiating 3T3-L1 cell line sampled at one or more time points under genetic or pharmacological perturbations. Data and metadata were obtained from the gene expression omnibus. The metadata were manually curated using unified language across the studies. Probe intensities were mapped and collapsed to genes using a reproducible pipeline. Samples were classified into none, genetically or pharmacologically modified. In addition to the clean datasets, two aggregated sets were further homogenized for illustration purposes. The curated datasets are available as an R/Bioconductor experimental data package curatedAdipoArray. The package documents the source code of the data collection, curation and processing. Finally, we used a subset of the data to effectively remove batch effects and reproduce biological observations. Database URL https://bioconductor.org/packages/curatedAdipoArray
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Affiliation(s)
- Mahmoud Ahmed
- Department of Biochemistry and Convergence Medical Sciences and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
| | - Do Sik Min
- College of Pharmacy, Yonsei University, Incheon, Republic of Korea
| | - Deok Ryong Kim
- Department of Biochemistry and Convergence Medical Sciences and Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Republic of Korea
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Trinchese G, Cavaliere G, Cimmino F, Catapano A, Carta G, Pirozzi C, Murru E, Lama A, Meli R, Bergamo P, Banni S, Mollica MP. Decreased Metabolic Flexibility in Skeletal Muscle of Rat Fed with a High-Fat Diet Is Recovered by Individual CLA Isomer Supplementation via Converging Protective Mechanisms. Cells 2020; 9:E823. [PMID: 32235294 PMCID: PMC7226748 DOI: 10.3390/cells9040823] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/26/2020] [Accepted: 03/28/2020] [Indexed: 12/15/2022] Open
Abstract
Energy balance, mitochondrial dysfunction, obesity, and insulin resistance are disrupted by metabolic inflexibility while therapeutic interventions are associated with improved glucose/lipid metabolism in skeletal muscle. Conjugated linoleic acid mixture (CLA) exhibited anti-obesity and anti-diabetic effects; however, the modulatory ability of its isomers (cis9, trans11, C9; trans10, cis12, C10) on the metabolic flexibility in skeletal muscle remains to be demonstrated. Metabolic inflexibility was induced in rat by four weeks of feeding with a high-fat diet (HFD). At the end of this period, the beneficial effects of C9 or C10 on body lipid content, energy expenditure, pro-inflammatory cytokines, glucose metabolism, and mitochondrial efficiency were examined. Moreover, oxidative stress markers, fatty acids, palmitoyletanolamide (PEA), and oleyletanolamide (OEA) contents along with peroxisome proliferator-activated receptors-alpha (PPARα), AKT, and adenosine monophosphate-activated protein kinase (AMPK) expression were evaluated in skeletal muscle to investigate the underlying biochemical mechanisms. The presented results indicate that C9 intake reduced mitochondrial efficiency and oxidative stress and increased PEA and OEA levels more efficiently than C10 while the anti-inflammatory activity of C10, and its regulatory efficacy on glucose homeostasis are associated with modulation of the PPARα/AMPK/pAKT signaling pathway. Our results support the idea that the dissimilar efficacy of C9 and C10 against the HFD-induced metabolic inflexibility may be consequential to their ability to activate different molecular pathways.
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Affiliation(s)
- Giovanna Trinchese
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (G.T.); (G.C.); (F.C.); (A.C.)
| | - Gina Cavaliere
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (G.T.); (G.C.); (F.C.); (A.C.)
| | - Fabiano Cimmino
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (G.T.); (G.C.); (F.C.); (A.C.)
| | - Angela Catapano
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (G.T.); (G.C.); (F.C.); (A.C.)
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy; (C.P.); (A.L.); (R.M.)
| | - Gianfranca Carta
- Department of Biomedical Sciences, University of Cagliari, Monserrato, CA 09042, Italy; (G.C.); (E.M.); (S.B.)
| | - Claudio Pirozzi
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy; (C.P.); (A.L.); (R.M.)
| | - Elisabetta Murru
- Department of Biomedical Sciences, University of Cagliari, Monserrato, CA 09042, Italy; (G.C.); (E.M.); (S.B.)
| | - Adriano Lama
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy; (C.P.); (A.L.); (R.M.)
| | - Rosaria Meli
- Department of Pharmacy, University of Naples Federico II, 80131 Naples, Italy; (C.P.); (A.L.); (R.M.)
| | - Paolo Bergamo
- Institute of Food Sciences, National Research Council, 83100 Avellino, Italy;
| | - Sebastiano Banni
- Department of Biomedical Sciences, University of Cagliari, Monserrato, CA 09042, Italy; (G.C.); (E.M.); (S.B.)
| | - Maria Pina Mollica
- Department of Biology, University of Naples Federico II, 80126 Naples, Italy; (G.T.); (G.C.); (F.C.); (A.C.)
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6
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Fu C, Zhang Y, Yao Q, Wei X, Shi T, Yan P, Liu X. Maternal conjugated linoleic acid alters hepatic lipid metabolism via the AMPK signaling pathway in chick embryos. Poult Sci 2020; 99:224-234. [PMID: 32416806 PMCID: PMC7587807 DOI: 10.3382/ps/pez462] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/31/2019] [Indexed: 01/13/2023] Open
Abstract
The effects of maternal conjugated linoleic acid (CLA) on embryonic development and hepatic lipid metabolism were investigated in chick embryos. A total of 180 Arbor Acres female broiler breeders (36 wk old) were randomly divided into the following 3 dietary treatment groups: a basic diet (control), a basic diet containing 0.5% CLA (CLA1), and a basic diet containing 1.0% CLA (CLA2). The females were fed for 8 wk, and the eggs from each group were collected and hatched during the last 2 wk. The results showed that the addition of dietary CLA increased the broken egg rate and reduced the fertilization rate and the egg hatchability (P < 0.05). CLA enrichment decreased the polyunsaturated and monounsaturated fatty acids and increased the saturated fatty acids in the yolk sac (P < 0.05). The yolk sac weight, body weight, and body length had a linear decrease with CLA supplementation (P < 0.05). In the developing chick embryo (at E14) and newly hatched chick (D0), the serum triglyceride concentration decreased with maternal CLA supplementation and was accompanied by a reduction in subcutaneous adipose tissue deposition. In addition, maternal CLA supplementation mediated the hepatic lipid metabolism by decreasing the mRNA expression of sterol regulatory element-binding proteins-1c (SREBP-1c), fatty acid synthase and acetyl-CoA carboxylase, and increasing the mRNA expression of adenosine 5'-monophosphate-activated protein kinase α (AMPKα), peroxisome proliferator-activated receptors α (PPARα), liver fatty acid-binding protein, adipose triglyceride lipase and carnitine palmitoyltransferase in embryonic chick livers (P < 0.05). A drop in SREBP-1c protein expression and an increase in the protein expression of p-AMPKα and PPARα were also observed in the liver of chick embryo (P < 0.05). In conclusion, maternal CLA supplementation regulated the fatty acid composition in the yolk sac, and mediated embryonic chick development and hepatic lipometabolism, and these effects may be related to the AMPK pathway. These findings suggest the potential ability of maternal CLA supplementation to reduce fat deposition in chick embryos.
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Affiliation(s)
- Chunyan Fu
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250023, China; Shandong Provincial Key Laboratory of Poultry Diseases Diagnosis and Immunology, Jinan 250023, China; Poultry Breeding Engineering Technology Center of Shandong Province, Jinan 250023, China
| | - Yan Zhang
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250023, China; Shandong Provincial Key Laboratory of Poultry Diseases Diagnosis and Immunology, Jinan 250023, China; Poultry Breeding Engineering Technology Center of Shandong Province, Jinan 250023, China
| | - Qimeng Yao
- Haiyang Animal Husbandry & Veterinary Station, Yantai 265100, China
| | - Xiangfa Wei
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250023, China; Shandong Provincial Key Laboratory of Poultry Diseases Diagnosis and Immunology, Jinan 250023, China; Poultry Breeding Engineering Technology Center of Shandong Province, Jinan 250023, China
| | - Tianhong Shi
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250023, China; Shandong Provincial Key Laboratory of Poultry Diseases Diagnosis and Immunology, Jinan 250023, China; Poultry Breeding Engineering Technology Center of Shandong Province, Jinan 250023, China
| | - Peipei Yan
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250023, China; Shandong Provincial Key Laboratory of Poultry Diseases Diagnosis and Immunology, Jinan 250023, China; Poultry Breeding Engineering Technology Center of Shandong Province, Jinan 250023, China
| | - Xuelan Liu
- Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250023, China; Shandong Provincial Key Laboratory of Poultry Diseases Diagnosis and Immunology, Jinan 250023, China; Poultry Breeding Engineering Technology Center of Shandong Province, Jinan 250023, China.
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7
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The soluble epoxide hydrolase determines cholesterol homeostasis by regulating AMPK and SREBP activity. Prostaglandins Other Lipid Mediat 2016; 125:30-9. [DOI: 10.1016/j.prostaglandins.2016.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 05/02/2016] [Accepted: 05/09/2016] [Indexed: 12/28/2022]
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8
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Wang W, Fromm M. Sphingolipids are required for efficient triacylglycerol loss in conjugated linoleic Acid treated adipocytes. PLoS One 2015; 10:e0119005. [PMID: 25906159 PMCID: PMC4407960 DOI: 10.1371/journal.pone.0119005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 01/13/2015] [Indexed: 11/19/2022] Open
Abstract
Conjugated linoleic acid (CLA) reduces adiposity in human and mouse adipocytes. This outcome is achieved through a variety of biological responses including increased energy expenditure and fatty acid oxidation, increased inflammation, repression of fatty acid biosynthesis, attenuated glucose transport, and apoptosis. In the current study, profiling of 261 metabolites was conducted to gain new insights into the biological pathways responding to CLA in 3T3-L1 adipocytes. Sphinganine and sphingosine levels were observed to be highly elevated in CLA treated adipocytes. Exogenous chemicals that increased endogenous ceramide levels decreased lipid levels in adipocytes, and activated AMP-activated protein kinase (AMPK) as well as NF-κB, both of which are typically activated in CLA treated adipocytes. Concurrent inhibition of ceramide de novo biosynthesis and recycling from existing sphingolipid pools attenuated the lipid lowering effect normally associated with responses to CLA, implicating ceramides as an important component of the lipid lowering response in CLA treated adipocytes.
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Affiliation(s)
- Wei Wang
- Department of Animal Science, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Michael Fromm
- Center for Biotechnology, University of Nebraska, Lincoln, Nebraska, United States of America
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9
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den Hartigh LJ, Han CY, Wang S, Omer M, Chait A. 10E,12Z-conjugated linoleic acid impairs adipocyte triglyceride storage by enhancing fatty acid oxidation, lipolysis, and mitochondrial reactive oxygen species. J Lipid Res 2013; 54:2964-78. [PMID: 23956445 DOI: 10.1194/jlr.m035188] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Conjugated linoleic acid (CLA) is a naturally occurring dietary trans fatty acid found in food from ruminant sources. One specific CLA isomer, 10E,12Z-CLA, has been associated with health benefits, such as reduced adiposity, while simultaneously promoting deleterious effects, such as systemic inflammation, insulin resistance, and dyslipidemia. The precise mechanisms by which 10E,12Z-CLA exerts these effects remain unknown. Despite potential health consequences, CLA continues to be advertised as a natural weight loss supplement, warranting further studies on its effects on lipid metabolism. We hypothesized that 10E,12Z-CLA impairs lipid storage in adipose tissue by altering the lipid metabolism of white adipocytes. We demonstrate that 10E,12Z-CLA reduced triglyceride storage due to enhanced fatty acid oxidation and lipolysis, coupled with diminished glucose uptake and utilization in cultured adipocytes. This switch to lipid utilization was accompanied by a potent proinflammatory response, including the generation of cytokines, monocyte chemotactic factors, and mitochondrial superoxide. Disrupting fatty acid oxidation restored glucose utilization and attenuated the inflammatory response to 10E,12Z-CLA, suggesting that fatty acid oxidation is critical in promoting this phenotype. With further investigation into the biochemical pathways involved in adipocyte responses to 10E,12Z-CLA, we can discern more information about its safety and efficacy in promoting weight loss.
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Affiliation(s)
- Laura J den Hartigh
- Diabetes Obesity Center for Excellence and the Department of Medicine, Division of Metabolism, Endocrinology and Nutrition, University of Washington, Seattle, WA 98109
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11
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Pimentel GD, Ropelle ER, Rocha GZ, Carvalheira JBC. The role of neuronal AMPK as a mediator of nutritional regulation of food intake and energy homeostasis. Metabolism 2013; 62:171-8. [PMID: 22898253 DOI: 10.1016/j.metabol.2012.07.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Revised: 07/01/2012] [Accepted: 07/06/2012] [Indexed: 02/07/2023]
Abstract
Hypothalamic 5'-adenosine monophosphate-activated protein kinase (AMPK) senses intracellular metabolic stress, i.e., an increase in the cellular AMP:ATP ratio, and integrates diverse hormonal and nutritional signals to restore energy balance. Recent evidence suggests that different nutrients can modulate AMPK activity in the hypothalamus, thereby controlling weight gain through a leptin-independent mechanism. Understanding the mechanisms by which nutrients control hypothalamic AMPK activity is crucial to the development of effective nutritional interventions for the treatment of food intake-related disorders, such as anorexia and obesity. This article highlights the current evidence for the intricate relationship between nutrients and hypothalamic AMPK activity.
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Affiliation(s)
- Gustavo D Pimentel
- Department of Internal Medicine, State University of Campinas, Campinas/São Paulo, Brazil
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12
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Jiang S, Wang W, Miner J, Fromm M. Cross regulation of sirtuin 1, AMPK, and PPARγ in conjugated linoleic acid treated adipocytes. PLoS One 2012; 7:e48874. [PMID: 23155420 PMCID: PMC3498327 DOI: 10.1371/journal.pone.0048874] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 10/02/2012] [Indexed: 02/04/2023] Open
Abstract
Trans-10, cis-12 conjugated linoleic acid (t10c12 CLA) reduces triglyceride (TG) levels in adipocytes through multiple pathways, with AMP-activated protein kinase (AMPK) generally facilitating, and peroxisome proliferator-activated receptor γ (PPARγ) generally opposing these reductions. Sirtuin 1 (SIRT1), a histone/protein deacetylase that affects energy homeostasis, often functions coordinately with AMPK, and is capable of binding to PPARγ, thereby inhibiting its activity. This study investigated the role of SIRT1 in the response of 3T3-L1 adipocytes to t10c12 CLA by testing the following hypotheses: 1) SIRT1 is functionally required for robust TG reduction; and 2) SIRT1, AMPK, and PPARγ cross regulate each other. These experiments were performed by using activators, inhibitors, or siRNA knockdowns that affected these pathways in t10c12 CLA-treated 3T3-L1 adipocytes. Inhibition of SIRT1 amounts or activity using siRNA, sirtinol, nicotinamide, or etomoxir attenuated the amount of TG loss, while SIRT1 activator SRT1720 increased the TG loss. SRT1720 increased AMPK activity while sirtuin-specific inhibitors decreased AMPK activity. Reciprocally, an AMPK inhibitor reduced SIRT1 activity. Treatment with t10c12 CLA increased PPARγ phosphorylation in an AMPK-dependent manner and increased the amount of PPARγ bound to SIRT1. Reciprocally, a PPARγ agonist attenuated AMPK and SIRT1 activity levels. These results indicated SIRT1 increased TG loss and that cross regulation between SIRT1, AMPK, and PPARγ occurred in 3T3-L1 adipocytes treated with t10c12 CLA.
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Affiliation(s)
- Shan Jiang
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Wei Wang
- Department of Animal Science, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Jess Miner
- Department of Animal Science, University of Nebraska, Lincoln, Nebraska, United States of America
| | - Michael Fromm
- Center for Biotechnology, University of Nebraska, Lincoln, Nebraska, United States of America
- * E-mail:
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13
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10E12Z CLA alters adipocyte differentiation and adipocyte cytokine expression and induces macrophage proliferation. J Nutr Biochem 2012; 23:510-8. [DOI: 10.1016/j.jnutbio.2011.02.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 02/16/2011] [Accepted: 02/17/2011] [Indexed: 12/26/2022]
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Abstract
Although many food components are reportedly beneficial to body-weight management, lack of understanding of molecular mechanisms and their function in overall adiposity under physiological conditions hinders successful and safe development of antiobesity functional foods. A positive energy balance resulting from an increase in food intake, a reduced energy expenditure, and/or dysfunction of adipose biology is associated with the development of obesity. This article provides an overview of the components involved in energy balance and adipose development and function. There is evidence that numerous ingredients found in foods can modulate energy balance and adipose biology, thereby potentially lowering adiposity.
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Affiliation(s)
- Kee-Hong Kim
- Department of Food Science, Purdue University, West Lafayette, Indiana 47907, USA.
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15
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Salgado JM, Ferreira TRB, Donado-Pestana CM, de Almeida OC, das Neves AMR, Mansi DN, Dias CTDS. Conjugated linoleic acid combined with physical activity reduces body fat accumulation but does not modify lean body mass in male and female Wistar rats. J Med Food 2011; 15:406-12. [PMID: 22191570 DOI: 10.1089/jmf.2011.0144] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Several biological and clinical studies have suggested that conjugated linoleic acid (CLA) prevents body fat accumulation and increases lean body mass. CLA is available as a concentrated dietary supplement and is purported to provide the aforementioned benefits for people who perform physical activity. This study was conducted to evaluate the effect of a CLA-supplemented diet combined with physical activity on the body composition of Wistar rats. Two groups of Wistar rats of both sexes, between 45 and 60 days old, were fed a diet containing 5.5% soybean oil (control group) or a CLA-supplemented diet (0.5% CLA and 5.0% soybean oil) (test group). Half the rats in both groups were assigned to exercise by running on a treadmill. The biochemical and anatomical body compositions were analyzed. In both groups, CLA had no effect on the dietary consumption or the weight of the liver, heart, and lungs. However, it did influence the overall weight gain of exercised male rats and the chemical and anatomical body composition in exercised and sedentary rats of both sexes. The results confirm that a CLA-supplemented diet with and without physical activity reduced body fat accumulation in rats of both sexes. However, there is no evidence of an increase in the lean body mass of the exercised rats.
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Affiliation(s)
- Jocelem Mastrodi Salgado
- Department of Agroindustry, Food and Nutrition, University of São Paulo, Piracicaba, São Paulo, Brazil.
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Jiang S, Chen H, Wang Z, Riethoven JJ, Xia Y, Miner J, Fromm M. Activated AMPK and prostaglandins are involved in the response to conjugated linoleic acid and are sufficient to cause lipid reductions in adipocytes. J Nutr Biochem 2010; 22:656-64. [PMID: 20965713 DOI: 10.1016/j.jnutbio.2010.05.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 12/18/2009] [Accepted: 05/20/2010] [Indexed: 11/20/2022]
Abstract
trans-10, cis-12 Conjugated linoleic acid (t10c12 CLA) reduces triglyceride levels in adipocytes. AMP-activated protein kinase (AMPK) and inflammation were recently demonstrated to be involved in the emerging pathways regulating this response. This study further investigated the role of AMPK and inflammation by testing the following hypotheses: (1) a moderate activation of AMPK and an inflammatory response are sufficient to reduce triglycerides, and (2) strong activation of AMPK is also sufficient. Experiments were performed by adding compounds that affect these pathways and by measuring their effects in 3T3-L1 adipocytes. A comparison of four AMPK activators (metformin, phenformin, TNF-α and t10c12 CLA) found a correlation between AMPK activity and triglyceride reduction. This correlation appeared to be modulated by the level of cyclo-oxygenase (COX)-2 mRNA produced. Inhibitors of the prostaglandin (PG) biosynthetic pathway interfered with t10c12 CLA's ability to reduce triglycerides. A combination of metformin and PGH2, or phenformin alone, efficiently reduced triglyceride levels in adipocytes. Microarray analysis indicated that the transcriptional responses to phenformin or t10c12 CLA were very similar, suggesting similar pathways were activated. 3T3-L1 fibroblasts were found to weakly induce the integrated stress response (ISR) in response to phenformin or t10c12 CLA and to respond robustly as they differentiated into adipocytes. This indicated that both chemicals required adipocytes at the same stage of differentiation to be competent for this response. These results support the above hypotheses and suggest compounds that moderately activate AMPK and increase PG levels or robustly activate AMPK in adipocytes may be beneficial for reducing adiposity.
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Affiliation(s)
- Shan Jiang
- Department of Animal Science, University of Nebraska, Lincoln, NE 68588-0665, USA
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Hsu YC, Meng X, Ou L, Ip MM. Activation of the AMP-activated protein kinase-p38 MAP kinase pathway mediates apoptosis induced by conjugated linoleic acid in p53-mutant mouse mammary tumor cells. Cell Signal 2010; 22:590-9. [PMID: 19932174 PMCID: PMC2838459 DOI: 10.1016/j.cellsig.2009.11.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Accepted: 11/13/2009] [Indexed: 12/20/2022]
Abstract
Conjugated linoleic acid (CLA) inhibits tumorigenesis and tumor growth in most model systems, an effect mediated in part by its pro-apoptotic activity. We previously showed that trans-10,cis-12 CLA induced apoptosis of p53-mutant TM4t mouse mammary tumor cells through both mitochondrial and endoplasmic reticulum stress pathways. In the current study, we investigated the role of AMP-activated protein kinase (AMPK), a key player in fatty acid metabolism, in CLA-induced apoptosis in TM4t cells. We found that t10,c12-CLA increased phosphorylation of AMPK, and that CLA-induced apoptosis was enhanced by the AMPK agonist 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) and inhibited by the AMPK inhibitor compound C. The increased AMPK activity was not due to nutrient/energy depletion since ATP levels did not change in CLA-treated cells, and knockdown of the upstream kinase LKB1 did not affect its activity. Furthermore, our data do not demonstrate a role for the AMPK-modulated mTOR pathway in CLA-induced apoptosis. Although CLA decreased mTOR levels, activity was only modestly decreased. Moreover, rapamycin, which completely blocked the activity of mTORC1 and mTORC2, did not induce apoptosis, and attenuated rather than enhanced CLA-induced apoptosis. Instead, the data suggest that CLA-induced apoptosis is mediated by the AMPK-p38 MAPK-Bim pathway: CLA-induced phosphorylation of AMPK and p38 MAPK, and increased expression of Bim, occurred with a similar time course as apoptosis; phosphorylation of p38 MAPK was blocked by compound C; the increased Bim expression was blocked by p38 MAPK siRNA; CLA-induced apoptosis was attenuated by the p38 inhibitor SB-203580 and by siRNAs directed against p38 MAPK or Bim.
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Affiliation(s)
- Yung-Chung Hsu
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
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