1
|
Leo S, Gattuso A, Mazza R, Filice M, Cerra MC, Imbrogno S. Cardiac influence of the β3-adrenoceptor in the goldfish ( Carassius auratus): a protective role under hypoxia? ACTA ACUST UNITED AC 2019; 222:jeb.211334. [PMID: 31527180 DOI: 10.1242/jeb.211334] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 09/11/2019] [Indexed: 12/18/2022]
Abstract
The goldfish (Carassius auratus) exhibits a remarkable capacity to survive and remain active under prolonged and severe hypoxia, making it a good model for studying cardiac function when oxygen availability is a limiting factor. Under hypoxia, the goldfish heart increases its performance, representing a putative component of hypoxia tolerance; however, the underlying mechanisms have not yet been elucidated. Here, we aimed to investigate the role of β3-adrenoreceptors (ARs) in the mechanisms that modulate goldfish heart performance along with the impact of oxygen levels. By western blotting analysis, we found that the goldfish heart expresses β3-ARs, and this expression increases under hypoxia. The effects of β3-AR stimulation were analysed by using an ex vivo working heart preparation. Under normoxia, the β3-AR-selective agonist BRL37344 (10-12 to 10-7 mol l-1) elicited a concentration-dependent increase of contractility that was abolished by a specific β3-AR antagonist (SR59230A; 10-8 mol l-1), but not by α/β1/β2-AR inhibitors (phentolamine, nadolol and ICI118,551; 10-7 mol l-1). Under acute hypoxia, BRL37344 did not affect goldfish heart performance. However, SR59230A, but not phentolamine, nadolol or ICI118,551, abolished the time-dependent enhancement of contractility that characterizes the hypoxic goldfish heart. Under both normoxia and hypoxia, adenylate cyclase and cAMP were found to be involved in the β3-AR-dependent downstream transduction pathway. In summary, we show the presence of functional β3-ARs in the goldfish heart, whose activation modulates basal performance and contributes to a hypoxia-dependent increase of contractility.
Collapse
Affiliation(s)
- Serena Leo
- Dept of Biology, Ecology and Earth Sciences (BEST), University of Calabria, Arcavacata di Rende (CS), Italy
| | - Alfonsina Gattuso
- Dept of Biology, Ecology and Earth Sciences (BEST), University of Calabria, Arcavacata di Rende (CS), Italy
| | - Rosa Mazza
- Dept of Biology, Ecology and Earth Sciences (BEST), University of Calabria, Arcavacata di Rende (CS), Italy
| | - Mariacristina Filice
- Dept of Biology, Ecology and Earth Sciences (BEST), University of Calabria, Arcavacata di Rende (CS), Italy
| | - Maria Carmela Cerra
- Dept of Biology, Ecology and Earth Sciences (BEST), University of Calabria, Arcavacata di Rende (CS), Italy
| | - Sandra Imbrogno
- Dept of Biology, Ecology and Earth Sciences (BEST), University of Calabria, Arcavacata di Rende (CS), Italy
| |
Collapse
|
2
|
Funcke JB, Scherer PE. Beyond adiponectin and leptin: adipose tissue-derived mediators of inter-organ communication. J Lipid Res 2019; 60:1648-1684. [PMID: 31209153 PMCID: PMC6795086 DOI: 10.1194/jlr.r094060] [Citation(s) in RCA: 176] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/17/2019] [Indexed: 01/10/2023] Open
Abstract
The breakthrough discoveries of leptin and adiponectin more than two decades ago led to a widespread recognition of adipose tissue as an endocrine organ. Many more adipose tissue-secreted signaling mediators (adipokines) have been identified since then, and much has been learned about how adipose tissue communicates with other organs of the body to maintain systemic homeostasis. Beyond proteins, additional factors, such as lipids, metabolites, noncoding RNAs, and extracellular vesicles (EVs), released by adipose tissue participate in this process. Here, we review the diverse signaling mediators and mechanisms adipose tissue utilizes to relay information to other organs. We discuss recently identified adipokines (proteins, lipids, and metabolites) and briefly outline the contributions of noncoding RNAs and EVs to the ever-increasing complexities of adipose tissue inter-organ communication. We conclude by reflecting on central aspects of adipokine biology, namely, the contribution of distinct adipose tissue depots and cell types to adipokine secretion, the phenomenon of adipokine resistance, and the capacity of adipose tissue to act both as a source and sink of signaling mediators.
Collapse
Affiliation(s)
- Jan-Bernd Funcke
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX
| | - Philipp E Scherer
- Touchstone Diabetes Center, University of Texas Southwestern Medical Center, Dallas, TX
| |
Collapse
|
3
|
Chinnakkannu P, Reese C, Gaspar JA, Panneerselvam S, Pleasant-Jenkins D, Mukherjee R, Baicu C, Tourkina E, Hoffman S, Kuppuswamy D. Suppression of angiotensin II-induced pathological changes in heart and kidney by the caveolin-1 scaffolding domain peptide. PLoS One 2018; 13:e0207844. [PMID: 30576317 PMCID: PMC6303044 DOI: 10.1371/journal.pone.0207844] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 11/07/2018] [Indexed: 01/15/2023] Open
Abstract
Dysregulation of the renin-angiotensin system leads to systemic hypertension and maladaptive fibrosis in various organs. We showed recently that myocardial fibrosis and the loss of cardiac function in mice with transverse aortic constriction (TAC) could be averted by treatment with the caveolin-1 scaffolding domain (CSD) peptide. Here, we used angiotensin II (AngII) infusion (2.1 mg/kg/day for 2 wk) in mice as a second model to confirm and extend our observations on the beneficial effects of CSD on heart and kidney disease. AngII caused cardiac hypertrophy (increased heart weight to body weight ratio (HW/BW) and cardiomyocyte cross-sectional area); fibrosis in heart and kidney (increased levels of collagen I and heat shock protein-47 (HSP47)); and vascular leakage (increased levels of IgG in heart and kidney). Echocardiograms of AngII-infused mice showed increased left ventricular posterior wall thickness (pWTh) and isovolumic relaxation time (IVRT), and decreased ejection fraction (EF), stroke volume (SV), and cardiac output (CO). CSD treatment (i.p. injections, 50 μg/mouse/day) of AngII-infused mice significantly suppressed all of these pathological changes in fibrosis, hypertrophy, vascular leakage, and ventricular function. AngII infusion increased β1 and β3 integrin levels and activated Pyk2 in both heart and kidney. These changes were also suppressed by CSD. Finally, bone marrow cell (BMC) isolated from AngII-infused mice showed hyper-migration toward SDF1. When AngII-infused mice were treated with CSD, BMC migration was reduced to the basal level observed in cells from control mice. Importantly, CSD did not affect the AngII-induced increase in blood pressure (BP), indicating that the beneficial effects of CSD were not mediated via normalization of BP. These results strongly indicate that CSD suppresses AngII-induced pathological changes in mice, suggesting that CSD can be developed as a treatment for patients with hypertension and pressure overload-induced heart failure.
Collapse
Affiliation(s)
- Panneerselvam Chinnakkannu
- Division of Cardiology, Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Charles Reese
- Division of Rheumatology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | | | - Saraswathi Panneerselvam
- Division of Cardiology, Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Dorea Pleasant-Jenkins
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Rupak Mukherjee
- Division of Cardiothoracic Surgery, Department of Surgery, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Catalin Baicu
- Division of Cardiology, Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Elena Tourkina
- Division of Rheumatology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Stanley Hoffman
- Division of Rheumatology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Dhandapani Kuppuswamy
- Division of Cardiology, Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston, South Carolina, United States of America
| |
Collapse
|
4
|
Yang F, Chen GX. Production of extracellular lysophosphatidic acid in the regulation of adipocyte functions and liver fibrosis. World J Gastroenterol 2018; 24:4132-4151. [PMID: 30271079 PMCID: PMC6158478 DOI: 10.3748/wjg.v24.i36.4132] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Revised: 04/24/2018] [Accepted: 05/05/2018] [Indexed: 02/06/2023] Open
Abstract
Lysophosphatidic acid (LPA), a glycerophospholipid, consists of a glycerol backbone connected to a phosphate head group and an acyl chain linked to sn-1 or sn-2 position. In the circulation, LPA is in sub-millimolar range and mainly derived from hydrolysis of lysophosphatidylcholine, a process mediated by lysophospholipase D activity in proteins such as autotaxin (ATX). Intracellular and extracellular LPAs act as bioactive lipid mediators with diverse functions in almost every mammalian cell type. The binding of LPA to its receptors LPA1-6 activates multiple cellular processes such as migration, proliferation and survival. The production of LPA and activation of LPA receptor signaling pathways in the events of physiology and pathophysiology have attracted the interest of researchers. Results from studies using transgenic and gene knockout animals with alterations of ATX and LPA receptors genes, have revealed the roles of LPA signaling pathways in metabolic active tissues and organs. The present review was aimed to summarize recent progresses in the studies of extracellular and intracellular LPA production pathways. This includes the functional, structural and biochemical properties of ATX and LPA receptors. The potential roles of LPA production and LPA receptor signaling pathways in obesity, insulin resistance and liver fibrosis are also discussed.
Collapse
Affiliation(s)
- Fang Yang
- School of Laboratory Medicine, Hubei University of Chinese Medicine, Wuhan 430065, Hubei Province, China
| | - Guo-Xun Chen
- Department of Nutrition, University of Tennessee at Knoxville, Knoxville, TN 37996, United States
| |
Collapse
|
5
|
Yang K, Zhao M, Huang J, Zhang C, Zheng Q, Chen Y, Jiang H, Lu W, Wang J. Pharmacological activation of PPARγ inhibits hypoxia-induced proliferation through a caveolin-1-targeted and -dependent mechanism in PASMCs. Am J Physiol Cell Physiol 2018; 314:C428-C438. [PMID: 29351409 DOI: 10.1152/ajpcell.00143.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Previously, we and others have demonstrated that activation of peroxisome proliferator-activated receptor γ (PPARγ) by specific pharmacological agonists inhibits the pathogenesis of chronic hypoxia-induced pulmonary hypertension (CHPH) by suppressing the proliferation and migration in distal pulmonary arterial smooth muscle cells (PASMCs). Moreover, these beneficial effects of PPARγ are mediated by targeting the intracellular calcium homeostasis and store-operated calcium channel (SOCC) proteins, including the main caveolae component caveolin-1. However, other than the caveolin-1 targeted mechanism, in this study, we further uncovered a caveolin-1 dependent mechanism within the activation of PPARγ by the specific agonist GW1929. First, effective knockdown of caveolin-1 by small-interfering RNA (siRNA) markedly abolished the upregulation of GW1929 on PPARγ expression at both mRNA and protein levels; Then, in HEK293T, which has previously been reported with low endogenous caveolin-1 expression, exogenous expression of caveolin-1 significantly enhanced the upregulation of GW1929 on PPARγ expression compared with nontransfection control. In addition, inhibition of PPARγ by either siRNA or pharmacological inhibitor T0070907 led to increased phosphorylation of cellular mitogen-activated protein kinases ERK1/2 and p38. In parallel, GW1929 dramatically decreased the expression of the proliferative regulators (cyclin D1 and PCNA), whereas it increased the apoptotic factors (p21, p53, and mdm2) in hypoxic PASMCs. Furthermore, these effects of GW1929 could be partially reversed by recovery of the drug treatment. In combination, PPARγ activation by GW1929 reversibly drove the cell toward an antiproliferative and proapoptotic phenotype in a caveolin-1-dependent and -targeted mechanism.
Collapse
Affiliation(s)
- Kai Yang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Mingming Zhao
- Laboratory of Molecular Biology and Immunology, National Institute on Aging, National Institutes of Health , Baltimore, Maryland
| | - Junyi Huang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Chenting Zhang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Qiuyu Zheng
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Yuqin Chen
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Haiyang Jiang
- Division of Pulmonary and Critical Care Medicine, The Johns Hopkins University School of Medicine , Baltimore, Maryland
| | - Wenju Lu
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China
| | - Jian Wang
- State Key Laboratory of Respiratory Diseases, Guangzhou Institute of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University , Guangzhou, Guangdong , China.,Division of Translational and Regenerative Medicine, Department of Medicine, University of Arizona College of Medicine , Tucson, Arizona
| |
Collapse
|
6
|
Imbrogno S, Gattuso A, Mazza R, Angelone T, Cerra MC. β3 -AR and the vertebrate heart: a comparative view. Acta Physiol (Oxf) 2015; 214:158-75. [PMID: 25809182 DOI: 10.1111/apha.12493] [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: 09/25/2014] [Revised: 11/04/2014] [Accepted: 03/16/2015] [Indexed: 01/13/2023]
Abstract
Recent cardiovascular research showed that, together with β1- and β2-adrenergic receptors (ARs), β3-ARs contribute to the catecholamine (CA)-dependent control of the heart. β3-ARs structure, function and ligands were investigated in mammals because of their applicative potential in human cardiovascular diseases. Only recently, the concept of a β3-AR-dependent cardiac modulation was extended to non-mammalian vertebrates, although information is still scarce and fragmentary. β3-ARs were structurally described in fish, showing a closer relationship to mammalian β1-AR than β2-AR. Functional β3-ARs are present in the cardiac tissue of teleosts and amphibians. As in mammals, activation of these receptors elicits a negative modulation of the inotropic performance through the involvement of the endothelium endocardium (EE), Gi/0 proteins and the nitric oxide (NO) signalling. This review aims to comparatively analyse data from literature on β3-ARs in mammals, with those on teleosts and amphibians. The purpose is to highlight aspects of uniformity and diversity of β3-ARs structure, ligands activity, function and signalling cascades throughout vertebrates. This may provide new perspectives aimed to clarify the biological relevance of β3-ARs in the context of the nervous and humoral control of the heart and its functional plasticity.
Collapse
Affiliation(s)
- S. Imbrogno
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
| | - A. Gattuso
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
| | - R. Mazza
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
| | - T. Angelone
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
- National Institute of Cardiovascular Research; Bologna Italy
| | - M. C. Cerra
- Department of Biology, Ecology and Earth Sciences; University of Calabria; Arcavacata di Rende Italy
- National Institute of Cardiovascular Research; Bologna Italy
| |
Collapse
|
7
|
Yu Q, Chen X, Fang X, Chen Q, Hu C. Caveolin-1 aggravates cigarette smoke extract-induced MUC5AC secretion in human airway epithelial cells. Int J Mol Med 2015; 35:1435-42. [PMID: 25776934 DOI: 10.3892/ijmm.2015.2133] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 03/04/2015] [Indexed: 11/06/2022] Open
Abstract
Airway mucus hypersecretion is a major pathological characteristic of chronic obstructive pulmonary disease (COPD), and cigarette smoke is highly implicated in mucus secretion and the development of COPD. Cigarette smoke reportedly induces mucin overproduction through the epidermal growth factor receptor (EGFR) in the airway epithelium; however, the underlying mechanisms responsible for the activation of EGFR remain unknown. Caveolin-1, a component protein in the cytomembrane, reportedly regulates airway inflammation and lung injury. In this study, we aimed to determine whether caveolin-1 modulates mucin hyperproduction induced by cigarette smoke. Our results revealed that cigarette smoke extract (CSE) significantly increased MUC5AC production, as well as the levels of phosphorylated EGFR (p-EGFR) and phosphorylated Akt (p-Akt) in human bronchial epithelial cells (16HBE cells), as shown by ELISA, RT-PCR and western blot analysis. These effects were prevented by treatment with EGFR inhibitor (AG1478) and phosphatidylinostol-3-kinase (PI3K) inhibitor (LY294002). We also found that the overexpression of caveolin-1 enhanced the expression of MUC5AC, p-EGFR and p-Akt induced by CSE. Conversely, the downregulation of caveolin-1 by siRNA against caveolin-1 inhibited the expression of MUC5AC, p-EGFR and p-Akt. Taken together, our data suggest that caveolin-1 enhances CSE-induced MUC5AC hypersecretion through the EGFR/PI3K/Akt signaling pathway.
Collapse
Affiliation(s)
- Qiao Yu
- Department of Gerontology and Respirology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Xi Chen
- Department of Gerontology and Respirology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Xia Fang
- Department of Gerontology and Respirology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Qiong Chen
- Department of Gerontology and Respirology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Chengping Hu
- Department of Gerontology and Respirology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| |
Collapse
|
8
|
Protein kinase a-mediated cell proliferation in brown preadipocytes is independent of Erk1/2, PI3K and mTOR. Exp Cell Res 2014; 328:143-155. [PMID: 25102377 DOI: 10.1016/j.yexcr.2014.07.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Revised: 07/18/2014] [Accepted: 07/22/2014] [Indexed: 02/03/2023]
Abstract
The physiological agonist norepinephrine promotes cell proliferation of brown preadipocytes during the process of tissue recruitment. In a primary culture system, cAMP mediates these adrenergic effects. In the present study, we demonstrated that, in contrast to other systems where the mitogenic effect of cAMP requires the synergistic action of (serum) growth factors, especially insulin/IGF, the cAMP effect in brown preadipocytes was independent of serum and insulin. Protein kinase A, rather than Epac, mediated the cAMP mitogenic effect. The Erk 1/2 family of MAPK, the PI3K system and the mTOR complexes were all activated by cAMP, but these activations were not necessary for cAMP-induced cell proliferation; a protein kinase C isoform may be involved in mediating cAMP-activated cell proliferation. We conclude that the generally acknowledged cellular mediators for induction of cell proliferation are not involved in this process in the brown preadipocyte system; this conclusion may be of relevance both for examination of mechanisms for induction of brown adipose tissue recruitment but also for understanding the mechanism behind e.g. certain endocrine neoplasias.
Collapse
|
9
|
Mukherjee R, Kim SW, Choi MS, Yun JW. Sex-dependent expression of caveolin 1 in response to sex steroid hormones is closely associated with development of obesity in rats. PLoS One 2014; 9:e90918. [PMID: 24608114 PMCID: PMC3948350 DOI: 10.1371/journal.pone.0090918] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 02/06/2014] [Indexed: 11/18/2022] Open
Abstract
Caveolin-1 (CAV1) is a conserved group of structural membrane proteins that form special cholesterol and sphingolipid-rich compartments, especially in adipocytes. Recently, it has been reported that CAV1 is an important target protein in sex hormone-dependent regulation of various metabolic pathways, particularly in cancer and diabetes. To clarify distinct roles of CAV1 in sex-dependent obesity development, we investigated the effects of high fat diet (HFD) and sex steroid hormones on CAV1 expression in adipose tissues of male and female rats. Results of animal experiments revealed that estrogen (17-β-estradiol, E2) and androgen (dihydrotestosterone, DHT) had opposite effects on body weight gain as well as on the regulation of CAV1, hormone sensitive lipase (HSL) and uncoupling protein 1 (UCP1) in adipose tissues. Furthermore, sex hormone receptors and aromatase were differentially expressed in a sex-dependent manner in response to E2 and DHT treatments. In vivo data were confirmed using 3T3-L1 and HIB1B cell lines, where Cav1 knock down stimulated lipogenesis but suppressed sex hormone receptor signaling proteins. Most importantly, co-immunoprecipitation enabled the identification of previously unrecognized CAV1-interacting mitochondrial or lipid oxidative pathway proteins in adipose tissues. Taken together, current data showed that CAV1 may play important preventive role in the development of obesity, with more prominent effects in females, and proved to be an important target protein for the hormonal regulation of adipose tissue metabolism by manipulating sex hormone receptors and mitochondrial oxidative pathways. Therefore, we can report, for the first time, the molecular mechanism underlying the effects of sex steroid hormones in the sex-dimorphic regulation of CAV1.
Collapse
Affiliation(s)
- Rajib Mukherjee
- Department of Biotechnology, Daegu University, Kyungsan, Republic of Korea
| | - Sang Woo Kim
- Department of Biotechnology, Daegu University, Kyungsan, Republic of Korea
| | - Myung Sook Choi
- Center for Food and Nutritional Genomics Research & Department of Food Science and Nutrition, Kyungpook National University, Daegu, Republic of Korea
| | - Jong Won Yun
- Department of Biotechnology, Daegu University, Kyungsan, Republic of Korea
- * E-mail:
| |
Collapse
|
10
|
In brown adipocytes, adrenergically induced β1-/β3-(Gs)-, α2-(Gi)- and α1-(Gq)-signalling to Erk1/2 activation is not mediated via EGF receptor transactivation. Exp Cell Res 2013; 319:2718-27. [DOI: 10.1016/j.yexcr.2013.08.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 08/02/2013] [Accepted: 08/05/2013] [Indexed: 11/15/2022]
|
11
|
Rancoule C, Dusaulcy R, Tréguer K, Grès S, Attané C, Saulnier-Blache JS. Involvement of autotaxin/lysophosphatidic acid signaling in obesity and impaired glucose homeostasis. Biochimie 2013; 96:140-3. [PMID: 23639740 DOI: 10.1016/j.biochi.2013.04.010] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 04/11/2013] [Indexed: 12/11/2022]
Abstract
Autotaxin (ATX) is a secreted lysophospholipase D involved in synthesis of lysophosphatidic acid (LPA), a phospholipid growth factor acting via specific receptors (LPA1R to LPA6R) and involved in several pathologies including obesity. ATX is secreted by adipocytes and contributes to circulating LPA. ATX expression is up-regulated in obese patients and mice in relationship with insulin resistance and impaired glucose tolerance. LPA1R is the most abundant subtype in adipose tissue. Its expression is higher in non-adipocyte cells than in adipocytes and is not altered in obesity. ATX increases and LPA1R decreases while preadipocytes differentiate into adipocytes (adipogenesis). LPA inhibits adipogenesis through down-regulation of the pro-adipogenic transcription factor PPARγ2. Adipocyte-specific knockout (FATX-KO) mice or mice treated with the LPAR antagonist Ki16425 gain more weight and accumulate more adipose tissue than wild type or control mice fed a high fat diet (HFD). These observations suggest that LPA (via LPA1R) exerts a tonic inhibitory effect on adipose tissue expansion that could, at least in part, result from the anti-adipogenic activity of LPA. A possible negative impact of LPA on insulin-sensitivity might also be considered. Despite being more sensitive to nutritional obesity, FATX-KO and Ki16425-treated mice fed a HFD show improved glucose tolerance when compared to wild type mice. Moreover, exogenously injected LPA acutely impairs glucose tolerance and insulin secretion. These observations show that LPA exerts a tonic deleterious impact on glucose homeostasis. In conclusion, ATX and LPA1R represent potential interesting pharmacological targets for the treatment of obesity-associated metabolic diseases.
Collapse
Affiliation(s)
- Chloé Rancoule
- Institut des maladies métaboliques et cardiovasculaires (I2MC), Inserm U1048. Université Paul Sabatier, Toulouse, France
| | | | | | | | | | | |
Collapse
|
12
|
Hadi T, Barrichon M, Mourtialon P, Wendremaire M, Garrido C, Sagot P, Bardou M, Lirussi F. Biphasic Erk1/2 activation sequentially involving Gs and Gi signaling is required in beta3-adrenergic receptor-induced primary smooth muscle cell proliferation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:1041-51. [PMID: 23388888 DOI: 10.1016/j.bbamcr.2013.01.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 01/02/2013] [Accepted: 01/18/2013] [Indexed: 01/13/2023]
Abstract
The beta3 adrenergic receptor (B3-AR) reportedly induces cell proliferation, but the signaling pathways that were proposed, involving either Gs or Gi coupling, remain controversial. To further investigate the role of G protein coupling in B3-AR induced proliferation, we stimulated primary human myometrial smooth muscle cells with SAR150640 (B3-AR agonist) in the absence or presence of variable G-protein inhibitors. Specific B3-AR stimulation led to an Erk1/2 induced proliferation. We observed that the proliferative effects of B3-AR require two Erk1/2 activation peaks (the first after 3min, the second at 8h). Erk1/2 activation at 3min was mimicked by forskolin (adenylyl-cyclase activator), and was resistant to pertussis toxin (Gi inhibitor), suggesting a Gs protein signaling. This first signaling also required the downstream Gs signaling effectors PKA and Src. However, Erk1/2 activation at 8h turned out to be pertussis toxin-dependent, and PKA-independent, indicating a Gi signaling pathway in which Src and PI3K were required. The pharmacological inhibition of both the Gs and Gi pathway abolished B3-AR-induced proliferation. Altogether, these data indicate that B3-AR-induced proliferation depends on the biphasic activation of Erk1/2 sequentially induced by the Gs/PKA/Src and Gi/Src/PI3K signaling pathways.
Collapse
|
13
|
Caveolin-1 deficiency leads to increased susceptibility to cell death and fibrosis in white adipose tissue: characterization of a lipodystrophic model. PLoS One 2012. [PMID: 23049990 DOI: 10.1371/journal.pone0046242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Caveolin-1 (CAV1) is an important regulator of adipose tissue homeostasis. In the present study we examined the impact of CAV1 deficiency on the properties of mouse adipose tissue both in vivo and in explant cultures during conditions of metabolic stress. In CAV1(-/-) mice fasting caused loss of adipose tissue mass despite a lack of hormone-sensitive lipase (HSL) phosphorylation. In addition, fasting resulted in increased macrophage infiltration, enhanced deposition of collagen, and a reduction in the level of the lipid droplet protein perilipin A (PLIN1a). Explant cultures of CAV1(-/-) adipose tissue also showed a loss of PLIN1a during culture, enhanced secretion of IL-6, increased release of lactate dehydrogenase, and demonstrated increased susceptibility to cell death upon collagenase treatment. Attenuated PKA-mediated signaling to HSL, loss of PLIN1a and increased secretion of IL-6 were also observed in adipose tissue explants of CAV1(+/+) mice with diet-induced obesity. Together these results suggest that while alterations in adipocyte lipid droplet biology support adipose tissue metabolism in the absence of PKA-mediated pro-lipolytic signaling in CAV1(-/-) mice, the tissue is intrinsically unstable resulting in increased susceptibility to cell death, which we suggest underlies the development of fibrosis and inflammation during periods of metabolic stress.
Collapse
|
14
|
Caveolin-1 deficiency leads to increased susceptibility to cell death and fibrosis in white adipose tissue: characterization of a lipodystrophic model. PLoS One 2012; 7:e46242. [PMID: 23049990 PMCID: PMC3458842 DOI: 10.1371/journal.pone.0046242] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 08/28/2012] [Indexed: 12/31/2022] Open
Abstract
Caveolin-1 (CAV1) is an important regulator of adipose tissue homeostasis. In the present study we examined the impact of CAV1 deficiency on the properties of mouse adipose tissue both in vivo and in explant cultures during conditions of metabolic stress. In CAV1−/− mice fasting caused loss of adipose tissue mass despite a lack of hormone-sensitive lipase (HSL) phosphorylation. In addition, fasting resulted in increased macrophage infiltration, enhanced deposition of collagen, and a reduction in the level of the lipid droplet protein perilipin A (PLIN1a). Explant cultures of CAV1−/− adipose tissue also showed a loss of PLIN1a during culture, enhanced secretion of IL-6, increased release of lactate dehydrogenase, and demonstrated increased susceptibility to cell death upon collagenase treatment. Attenuated PKA-mediated signaling to HSL, loss of PLIN1a and increased secretion of IL-6 were also observed in adipose tissue explants of CAV1+/+ mice with diet-induced obesity. Together these results suggest that while alterations in adipocyte lipid droplet biology support adipose tissue metabolism in the absence of PKA-mediated pro-lipolytic signaling in CAV1−/− mice, the tissue is intrinsically unstable resulting in increased susceptibility to cell death, which we suggest underlies the development of fibrosis and inflammation during periods of metabolic stress.
Collapse
|
15
|
Abstract
PURPOSE OF REVIEW The finding that brown adipose tissue (BAT) is present in adults brought BAT physiology into the focus of many researchers interested in energy metabolism. Here, we review recent insight into how BAT develops, functions and might help to treat metabolic disorders in humans. RECENT FINDINGS BAT is under control of the nervous system, and several pathways have been identified that allow direct manipulation of BAT biology. In addition, some brown adipocytes arise from a distinct subset of white adipocyte precursors and studies were performed that characterize the development of these 'brite' adipocytes. Importantly, progress has been made in understanding how BAT takes up and dissipates nutrients that in metabolic disorders are present in excess. Finally, as it seems that BAT activity declines with age and obesity, we review findings that might shed light on how humans could sustain or increase BAT activity, thus preventing or treating obesity, hyperlipidemia and type 2 diabetes. SUMMARY BAT is a powerful organ that controls the development of metabolic disease. These powers are boosted by mechanisms that turn white into brown fat and enhance lipid flux into BAT. However, in humans, it remains unclear what was the first: metabolic disease or decreased BAT activity.
Collapse
Affiliation(s)
- Alexander Bartelt
- Department of Biochemistry and Molecular Cell Biology Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | |
Collapse
|
16
|
Andersson ER. The role of endocytosis in activating and regulating signal transduction. Cell Mol Life Sci 2012; 69:1755-71. [PMID: 22113372 PMCID: PMC11114983 DOI: 10.1007/s00018-011-0877-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 10/23/2011] [Accepted: 10/24/2011] [Indexed: 02/07/2023]
Abstract
Endocytosis is increasingly understood to play crucial roles in most signaling pathways, from determining which signaling components are activated, to how the signal is subsequently transduced and/or terminated. Whether a receptor-ligand complex is internalized via a clathrin-dependent or clathrin-independent endocytic route, and the complexes' subsequent trafficking through specific endocytic compartments, to then be recycled or degraded, has profound effects on signaling output. This review discusses the roles of endocytosis in three markedly different signaling pathways: the Wnt, Notch, and Eph/Ephrin pathways. These offer fundamentally different signaling systems: (1) diffusible ligands inducing signaling in one cell, (2) membrane-tethered ligands inducing signaling in a contacting receptor cell, and (3) bi-directional receptor-ligand signaling in two contacting cells. In each of these systems, endocytosis controls signaling in fascinating ways, and comparison of their similarities and dissimilarities will help to expand our understanding of endocytic control of signal transduction across multiple signaling pathways.
Collapse
Affiliation(s)
- Emma R Andersson
- Department of Cell and Molecular Biology, Karolinska Institute, 171 77, Stockholm, Sweden.
| |
Collapse
|
17
|
Abstract
Caveolins (Cavs) are integrated plasma membrane proteins that are complex signaling regulators with numerous partners and whose activity is highly dependent on cellular context. Cavs are both positive and negative regulators of cell signaling in and/or out of caveolae, invaginated lipid raft domains whose formation is caveolin expression dependent. Caveolins and rafts have been implicated in membrane compartmentalization; proteins and lipids accumulate in these membrane microdomains where they transmit fast, amplified and specific signaling cascades. The concept of plasma membrane organization within functional rafts is still in exploration and sometimes questioned. In this chapter, we discuss the opposing functions of caveolin in cell signaling regulation focusing on the role of caveolin both as a promoter and inhibitor of different signaling pathways and on the impact of membrane domain localization on caveolin functionality in cell proliferation, survival, apoptosis and migration.
Collapse
|
18
|
Sato M, Hutchinson DS, Halls ML, Furness SGB, Bengtsson T, Evans BA, Summers RJ. Interaction with caveolin-1 modulates G protein coupling of mouse β3-adrenoceptor. J Biol Chem 2012; 287:20674-88. [PMID: 22535965 DOI: 10.1074/jbc.m111.280651] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Caveolins act as scaffold proteins in multiprotein complexes and have been implicated in signaling by G protein-coupled receptors. Studies using knock-out mice suggest that β(3)-adrenoceptor (β(3)-AR) signaling is dependent on caveolin-1; however, it is not known whether caveolin-1 is associated with the β(3)-AR or solely with downstream signaling proteins. We have addressed this question by examining the impact of membrane rafts and caveolin-1 on the differential signaling of mouse β(3a)- and β(3b)-AR isoforms that diverge at the distal C terminus. Only the β(3b)-AR promotes pertussis toxin (PTX)-sensitive cAMP accumulation. When cells expressing the β(3a)-AR were treated with filipin III to disrupt membrane rafts or transfected with caveolin-1 siRNA, the cyclic AMP response to the β(3)-AR agonist CL316243 became PTX-sensitive, suggesting Gα(i/o) coupling. The β(3a)-AR C terminus, SP(384)PLNRF(389)DGY(392)EGARPF(398)PT, resembles a caveolin interaction motif. Mutant β(3a)-ARs (F389A/Y392A/F398A or P384S/F389A) promoted PTX-sensitive cAMP responses, and in situ proximity assays demonstrated an association between caveolin-1 and the wild type β(3a)-AR but not the mutant receptors. In membrane preparations, the β(3b)-AR activated Gα(o) and mediated PTX-sensitive cAMP responses, whereas the β(3a)-AR did not activate Gα(i/o) proteins. The endogenous β(3a)-AR displayed Gα(i/o) coupling in brown adipocytes from caveolin-1 knock-out mice or in wild type adipocytes treated with filipin III. Our studies indicate that interaction of the β(3a)-AR with caveolin inhibits coupling to Gα(i/o) proteins and suggest that signaling is modulated by a raft-enriched complex containing the β(3a)-AR, caveolin-1, Gα(s), and adenylyl cyclase.
Collapse
Affiliation(s)
- Masaaki Sato
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and the Department of Pharmacology, Monash University, Parkville, Victoria 3052, Australia
| | | | | | | | | | | | | |
Collapse
|
19
|
Federico L, Ren H, Mueller PA, Wu T, Liu S, Popovic J, Blalock EM, Sunkara M, Ovaa H, Albers HM, Mills GB, Morris AJ, Smyth SS. Autotaxin and its product lysophosphatidic acid suppress brown adipose differentiation and promote diet-induced obesity in mice. Mol Endocrinol 2012; 26:786-97. [PMID: 22474126 DOI: 10.1210/me.2011-1229] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Brown adipose tissue is a thermogenic organ that dissipates stored energy as heat to maintain body temperature. This process may also provide protection from development of diet-induced obesity. We report that the bioactive lipid mediator lysophosphatidic acid (LPA) markedly decreases differentiation of cultured primary brown adipocyte precursors, whereas potent selective inhibitors of the LPA-generating enzyme autotaxin (ATX) promote differentiation. Transgenic mice overexpressing ATX exhibit reduced expression of brown adipose tissue-related genes in peripheral white adipose tissue and accumulate significantly more fat than wild-type controls when fed a high-fat diet. Our results indicate that ATX and its product LPA are physiologically relevant negative regulators of brown fat adipogenesis and are consistent with a model in which a decrease in mature peripheral brown adipose tissue results in increased susceptibility to diet-induced obesity in mice.
Collapse
Affiliation(s)
- Lorenzo Federico
- Division of Cardiovascular Medicine, University of Kentucky, Lexington, Kentucky 40536, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Kitao N, Hashimoto M. Increased thermogenic capacity of brown adipose tissue under low temperature and its contribution to arousal from hibernation in Syrian hamsters. Am J Physiol Regul Integr Comp Physiol 2011; 302:R118-25. [PMID: 21993529 DOI: 10.1152/ajpregu.00053.2011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Brown adipose tissue (BAT) is thought to play a significant physiological role during arousal when body temperature rises from the extremely low body temperature that occurs during hibernation. The dominant pathway of BAT thermogenesis occurs through the β(3)-adrenergic receptor. In this study, we investigated the role of the β(3)-adrenergic system in BAT thermogenesis during arousal from hibernation both in vitro and in vivo. Syrian hamsters in the hibernation group contained BAT that was significantly greater in overall mass, total protein, and thermogenic uncoupling protein-1 than BAT from the warm-acclimated group. Although the ability of the β(3)-agonist CL316,243 to induce BAT thermogenesis at 36°C was no different between the hibernation and warm-acclimated groups, its maximum ratio over the basal value at 12°C in the hibernation group was significantly larger than that in the warm-acclimated group. Forskolin stimulation at 12°C produced equivalent BAT responses in these two groups. In vivo thermogenesis was assessed with the arousal time determined by the time course of BAT temperature or heart rate. Stimulation of BAT by CL316,243 significantly shortened the time of arousal from hibernation compared with that induced by vehicle alone, and it also induced arousal in deep hibernating animals. The β(3)-antagonist SR59230A inhibited arousal from hibernation either in part or completely. These results suggest that BAT in hibernating animals has potent thermogenic activity with a highly effective β(3)-receptor mechanism at lower temperatures.
Collapse
Affiliation(s)
- Naoya Kitao
- Department of Physiology, Asahikawa Medical University, Japan
| | | |
Collapse
|
21
|
Jasmin JF, Rengo G, Lymperopoulos A, Gupta R, Eaton GJ, Quann K, Gonzales DM, Mercier I, Koch WJ, Lisanti MP. Caveolin-1 deficiency exacerbates cardiac dysfunction and reduces survival in mice with myocardial infarction. Am J Physiol Heart Circ Physiol 2011; 300:H1274-81. [PMID: 21297026 DOI: 10.1152/ajpheart.01173.2010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Caveolin (Cav)-1 has been involved in the pathogenesis of ischemic injuries. For instance, modulations of Cav-1 expression have been reported in animal models of myocardial infarction and cerebral ischemia-reperfusion. Furthermore, ablation of the Cav-1 gene in mice has been shown to increase the extent of ischemic injury in models of cerebral and hindlimb ischemia. Cav-1 has also been suggested to play a role in myocardial ischemic preconditioning. However, the role of Cav-1 in myocardial ischemia (MI)-induced cardiac dysfunction still remains to be determined. We determined the outcome of a permanent left anterior descending coronary artery (LAD) ligation in Cav-1 knockout (KO) mice. Wild-type (WT) and Cav-1 KO mice were subjected to permanent LAD ligation for 24 h. The progression of ischemic injury was monitored by echocardiography, hemodynamic measurements, 2,3,5-triphenyltetrazolium chloride staining, β-binding analysis, cAMP level measurements, and Western blot analyses. Cav-1 KO mice subjected to LAD ligation display reduced survival compared with WT mice. Despite similar infarct sizes, Cav-1 KO mice subjected to MI showed reduced left ventricular (LV) ejection fraction and fractional shortening as well as increased LV end-diastolic pressures compared with their WT counterparts. Mechanistically, Cav-1 KO mice subjected to MI exhibit reduced β-adrenergic receptor density at the plasma membrane as well as decreased cAMP levels and PKA phosphorylation. In conclusion, ablation of the Cav-1 gene exacerbates cardiac dysfunction and reduces survival in mice subjected to MI. Mechanistically, Cav-1 KO mice subjected to LAD ligation display abnormalities in β-adrenergic signaling.
Collapse
Affiliation(s)
- Jean-François Jasmin
- Department of Stem Cell Biology and Regenerative Medicine, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Mattsson CL, Csikasz RI, Shabalina IG, Nedergaard J, Cannon B. Caveolin-1-ablated mice survive in cold by nonshivering thermogenesis despite desensitized adrenergic responsiveness. Am J Physiol Endocrinol Metab 2010; 299:E374-83. [PMID: 20530737 DOI: 10.1152/ajpendo.00071.2010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Caveolin-1 (Cav1)-ablated mice display impaired lipolysis in white adipose tissue. They also seem to have an impairment in brown adipose tissue function, implying that Cav1-ablated mice could encounter problems in surviving longer periods in cold temperatures. To investigate this, Cav1-ablated mice and wild-type mice were transferred to cold temperatures for extended periods of time, and parameters related to metabolism and thermogenesis were investigated. Unexpectedly, the Cav1-ablated mice survived in the cold. There were no differences between Cav1-ablated and wild-type mice with regard to food intake, in behavior related to shivering, or in body temperature. The Cav1-ablated mice had a halved total fat content independently of acclimation temperature. There was no difference in brown adipose tissue uncoupling protein-1 (UCP1) protein amount, and isolated brown fat mitochondria were thermogenically competent but displayed 30% higher thermogenic capacity. However, the beta(3)-adrenergic receptor amount was reduced by about one-third in the Cav1-ablated mice at all acclimation temperatures. Principally in accordance with this, a higher than standard dose of norepinephrine was needed to obtain full norepinephrine-induced thermogenesis in the Cav1-ablated mice; the higher dose was also needed for the Cav1-ablated mice to be able to utilize fat as a substrate for thermogenesis. In conclusion, the ablation of Cav1 impairs brown adipose tissue function by a desensitization of the adrenergic response; however, the desensitization is not evident in the animal as it is overcome physiologically, and Cav1-ablated mice can therefore survive in prolonged cold by nonshivering thermogenesis.
Collapse
|