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Tang Y, Yu Y, Li R, Tao Z, Zhang L, Wang X, Qi X, Li Y, Meng T, Qu H, Zhou M, Xu J, Liu J. Phenylalanine promotes alveolar macrophage pyroptosis via the activation of CaSR in ARDS. Front Immunol 2023; 14:1114129. [PMID: 37377971 PMCID: PMC10291621 DOI: 10.3389/fimmu.2023.1114129] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 05/17/2023] [Indexed: 06/29/2023] Open
Abstract
Acute respiratory distress syndrome (ARDS) is associated with high mortality rates in patients admitted to the intensive care unit (ICU) patients with overwhelming inflammation considered to be an internal cause. The authors' previous study indicated a potential correlation between phenylalanine levels and lung injury. Phenylalanine induces inflammation by enhancing the innate immune response and the release of pro-inflammatory cytokines. Alveolar macrophages (AMs) can respond to stimuli via synthesis and release of inflammatory mediators through pyroptosis, one form of programmed cell death acting through the nucleotide-binging oligomerization domain-like receptors protein 3 (NLRP3) signaling pathway, resulting in the cleavage of caspase-1 and gasdermin D (GSDMD) and the release of interleukin (IL) -1β and IL-18, aggravating lung inflammation and injury in ARDS. In this study, phenylalanine promoted pyroptosis of AMs, which exacerbated lung inflammation and ARDS lethality in mice. Furthermore, phenylalanine initiated the NLRP3 pathway by activating the calcium-sensing receptor (CaSR). These findings uncovered a critical mechanism of action of phenylalanine in the context of ARDS and may be a new treatment target for ARDS.
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Affiliation(s)
- Yiding Tang
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yue Yu
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Ranran Li
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zheying Tao
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Li Zhang
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaoli Wang
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiaoling Qi
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yinjiaozhi Li
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Tianjiao Meng
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hongping Qu
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Mi Zhou
- Department of Cardiac Surgery, Ruijin Hospital affiliated to School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jing Xu
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jialin Liu
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Werner LE, Wagner U. Calcium-sensing receptor-mediated NLRP3 inflammasome activation in rheumatoid arthritis and autoinflammation. Front Physiol 2023; 13:1078569. [PMID: 36685206 PMCID: PMC9854345 DOI: 10.3389/fphys.2022.1078569] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 11/17/2022] [Indexed: 01/09/2023] Open
Abstract
The calcium-sensing receptor (CaSR) is expressed in many cell types - including immune cells and in particular circulating monocytes. Here, the receptor plays an important physiological role as a regulator of constitutive macropinocytosis. This review article provides an overview of the literature on the role of the calcium sensing receptor in the context of inflammatory processes. Special emphasis is laid upon the importance for monocytes in the context of rheumatoid arthritis. We have shown previously, that stimulation of the receptor by increased extracellular Ca2+ ([Ca2+]ex) triggers a pro-inflammatory response due to NLRP3 inflammasome assembly and interleukin (IL)-1β release. The underlying mechanism includes macropinocytosis of calciprotein particles (CPPs), which are taken up in a [Ca2+]ex-induced, CaSR dependent manner, and leads to strong IL-1β release. In rheumatoid arthritis (RA), this uptake and the resulting IL-1β release is significantly increased due to increased expression of the receptor. Moreover, increased [Ca2+]ex-induced CPP uptake and IL-1β release is associated with more active disease, while CaSR overexpression has been reported to be associated with cardiovascular complications of RA. Most importantly, however, in animal experiments with arthritic mice, increased local calcium concentrations are present, which in combination with release of fetuin-A from eroded bone could contribute to formation of CPPs. We propose, that increased [Ca2+]ex, CPPs and pro-inflammatory cytokines drive a vicious cycle of inflammation and bone destruction which in turn offers new potential therapeutic approaches.
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Iamartino L, Brandi ML. The calcium-sensing receptor in inflammation: Recent updates. Front Physiol 2022; 13:1059369. [PMID: 36467702 PMCID: PMC9716066 DOI: 10.3389/fphys.2022.1059369] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 11/07/2022] [Indexed: 07/30/2023] Open
Abstract
The Calcium-Sensing Receptor (CaSR) is a member of the class C of G-proteins coupled receptors (GPCRs), it plays a pivotal role in calcium homeostasis by directly controlling calcium excretion in the kidneys and indirectly by regulating parathyroid hormone (PTH) release from the parathyroid glands. The CaSR is found to be ubiquitously expressed in the body, playing a plethora of additional functions spanning from fluid secretion, insulin release, neuronal development, vessel tone to cell proliferation and apoptosis, to name but a few. The present review aims to elucidate and clarify the emerging regulatory effects that the CaSR plays in inflammation in several tissues, where it mostly promotes pro-inflammatory responses, with the exception of the large intestine, where contradictory roles have been recently reported. The CaSR has been found to be expressed even in immune cells, where it stimulates immune response and chemokinesis. On the other hand, CaSR expression seems to be boosted under inflammatory stimulus, in particular, by pro-inflammatory cytokines. Because of this, the CaSR has been addressed as a key factor responsible for hypocalcemia and low levels of PTH that are commonly found in critically ill patients under sepsis or after burn injury. Moreover, the CaSR has been found to be implicated in autoimmune-hypoparathyroidism, recently found also in patients treated with immune-checkpoint inhibitors. Given the tight bound between the CaSR, calcium and vitamin D metabolism, we also speculate about their roles in the pathogenesis of severe acute respiratory syndrome coronavirus-19 (SARS-COVID-19) infection and their impact on patients' prognosis. We will further explore the therapeutic potential of pharmacological targeting of the CaSR for the treatment and management of aberrant inflammatory responses.
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Affiliation(s)
- Luca Iamartino
- Department of Experimental Clinical and Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
| | - Maria Luisa Brandi
- F.I.R.M.O. (Italian Foundation for the Research on Bone Diseases), Florence, Italy
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Apigenin and apigenin-7, 4'-O-dioctanoate protect against acrolein-aggravated inflammation via inhibiting the activation of NLRP3 inflammasome and HMGB1/MYD88/NF-κB signaling pathway in Human umbilical vein endothelial cells (HUVEC). Food Chem Toxicol 2022; 168:113400. [PMID: 36055550 DOI: 10.1016/j.fct.2022.113400] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 08/05/2022] [Accepted: 08/26/2022] [Indexed: 12/29/2022]
Abstract
Exposure to acrolein, one environmental and dietary pollutant, has been shown to cause inflammation. Here, we reported for the first time that acrolein aggravated lipopolysaccharide (LPS)-induced inflammation in Human umbilical vein endothelial cells (HUVEC) as evidenced by the further increased mRNA expression of three pro-inflammatory cytokines, including interleukin 1β (IL-1β), interleukin 6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Acrolein also further increased the generation of reactive oxygen species (ROS) and decreased the activity of glutathione peroxidase (GSH-Px) in LPS-pretreated HUVEC. Moreover, acrolein treatment further increased the nucleotide oligomerization domain-like receptor protein 3 (NLRP3) and apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) expression, caspase-1 cleavage, and downstream matures interleukin 18 (IL-18) and IL-1β level in LPS-pretreated HUVEC. Acrolein treatment also further increased the expressions of high-mobility group box 1 (HMGB1), toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and phospho-NF-κB P65 (P-P65) in the LPS pre-treated HUVEC. Thus, acrolein aggravated LPS-induced HUVEC inflammation through induction of oxidative stress, and activation of NLRP3 inflammasome and HMGB1/MYD88/NF-κB signaling pathway. In addition, apigenin and apigenin-7, 4'-O-dioctanoate attenuated acrolein-aggravated inflammation by targeting the above signaling pathways. Our findings could help to develop potential therapeutic strategies against acrolein-enhanced inflammation.
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Thrum S, Sommer M, Raulien N, Gericke M, Massier L, Kovacs P, Krasselt M, Landgraf K, Körner A, Dietrich A, Blüher M, Rossol M, Wagner U. Macrophages in obesity are characterised by increased IL-1β response to calcium-sensing receptor signals. Int J Obes (Lond) 2022; 46:1883-1891. [PMID: 35931812 PMCID: PMC9492543 DOI: 10.1038/s41366-022-01135-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 03/10/2022] [Accepted: 04/28/2022] [Indexed: 11/29/2022]
Abstract
Objective Obesity is complicated by inflammatory activation of the innate immune system. Stimulation of the calcium-sensing receptor (CaSR) by extra-cellular calcium ions ([Ca2+]ex) can trigger NLRP3 inflammasome activation and inflammation. We hypothesised, that this mechanism might contribute to the activation of adipose tissue (AT) in obesity, and investigated [Ca2+]ex-induced, CaSR mediated IL-1β release by macrophages in obesity. Methods [Ca2+]ex-induced IL-1β release was investigated in monocyte-derived macrophages (MDM) generated from peripheral blood of patients with obesity and from normal-weight controls. Visceral and subcutaneous AT biosamples were stimulated with [Ca2+]ex, and IL-1β release, as well as expression of NLRP3 inflammasome and cytokine genes, was determined. Results Both MDM and AT readily responded with concentration-dependent IL-1β release already at low, near physiological concentrations to addition of [Ca2+]ex, which was more than 80 fold higher than the LPS-induced effect. IL-1β levels induced by [Ca2+]ex were significantly higher not only in MDM from patients with obesity compared to controls, but also in visceral versus subcutaneous AT. This fat-depot difference was also reflected by mRNA expression levels of inflammasome and cytokine genes. Conclusions Obesity renders macrophages more susceptible to [Ca2+]ex-induced IL-1β release and pyroptosis. Increased susceptibility was independent of the response to LPS and circulating CRP arguing against mere pro-inflammatory pre-activation of monocytes. Instead, we propose that CaSR mediated signalling is relevant for the deleterious innate immune activation in obesity.
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Affiliation(s)
- Stephan Thrum
- Medical Department III, Leipzig University, Leipzig, Germany.,Integrated Research and Treatment Center (IFB) Adiposity Diseases, University of Leipzig, Leipzig, Germany
| | - Miriam Sommer
- Medical Department III, Leipzig University, Leipzig, Germany.,Integrated Research and Treatment Center (IFB) Adiposity Diseases, University of Leipzig, Leipzig, Germany
| | - Nora Raulien
- Institute of Anatomy and Cell Biology, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Martin Gericke
- Institute of Anatomy and Cell Biology, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Lucas Massier
- Medical Department III, Leipzig University, Leipzig, Germany
| | - Peter Kovacs
- Medical Department III, Leipzig University, Leipzig, Germany.,Integrated Research and Treatment Center (IFB) Adiposity Diseases, University of Leipzig, Leipzig, Germany
| | - Marco Krasselt
- Medical Department III, Leipzig University, Leipzig, Germany
| | - Kathrin Landgraf
- Center for Pediatric Research Leipzig, University Hospital for Children & Adolescents, Department of Women's and Child Health, University of Leipzig, Leipzig, Germany
| | - Antje Körner
- Center for Pediatric Research Leipzig, University Hospital for Children & Adolescents, Department of Women's and Child Health, University of Leipzig, Leipzig, Germany
| | - Arne Dietrich
- Clinic for Visceral, Transplantation and Thorax and Vascular Surgery, Leipzig University, Leipzig, Germany
| | - Matthias Blüher
- Medical Department III, Leipzig University, Leipzig, Germany
| | - Manuela Rossol
- Medical Department III, Leipzig University, Leipzig, Germany
| | - Ulf Wagner
- Medical Department III, Leipzig University, Leipzig, Germany.
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Liu W, Guo Y, Liu Y, Sun J, Yin X. Calcium-Sensing Receptor of Immune Cells and Diseases. CARDIOVASCULAR INNOVATIONS AND APPLICATIONS 2021. [DOI: 10.15212/cvia.2021.0009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Calcium-sensing receptor (CaSR), which was initially found in the parathyroid gland, is ubiquitously expressed and exerts specific functions in multiple cells, including immune cells. CaSR is functionally expressed on neutrophils, monocytes/macrophages, and T lymphocytes, but not B
lymphocytes, and regulates cell functions, such as cytokine secretion, chemotaxis, phenotype switching, and ligand delivery. In these immune cells, CaSR is involved in the development of many diseases, such as sepsis, cryopyrin-associated periodic syndromes, rheumatism, myocardial infarction,
diabetes, and peripheral artery disease. Since its discovery, it has been controversial whether CaSR is expressed and plays a role in immune cells. This article reviews current knowledge of the role of CaSR in immune cells.
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Affiliation(s)
- Wenxiu Liu
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001 Heilongjiang, China
| | - Yutong Guo
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001 Heilongjiang, China
| | - Yue Liu
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001 Heilongjiang, China
| | - Jiaxing Sun
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001 Heilongjiang, China
| | - Xinhua Yin
- Department of Cardiology, The First Affiliated Hospital of Harbin Medical University, Harbin, 150001 Heilongjiang, China
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Yan Z, Qi Z, Yang X, Ji N, Wang Y, Shi Q, Li M, Zhang J, Zhu Y. The NLRP3 inflammasome: Multiple activation pathways and its role in primary cells during ventricular remodeling. J Cell Physiol 2021; 236:5547-5563. [PMID: 33469931 DOI: 10.1002/jcp.30285] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/04/2021] [Accepted: 01/06/2021] [Indexed: 12/18/2022]
Abstract
Inflammasomes are a group of multiprotein signaling complexes located in the cytoplasm. Several inflammasomes have been identified, including NLRP1, NLRP2, NLRP3, AIM2, and NLRC4. Among them, NLRP3 was investigated in most detail, and it was reported that it can be activated by many different stimuli. Increased NLRP3 protein expression and inflammasome assembly lead to caspase-1 mediated maturation and release of IL-1β, which triggers inflammation and pyroptosis. The activation of the NLRP3 inflammasome has been widely reported in studies of tumors and neurological diseases, but relatively few studies on the cardiovascular system. Ventricular remodeling (VR) is an important factor contributing to heart failure (HF) after myocardial infarction (MI). Consequently, delaying VR is of great significance for improving heart function. Studies have shown that the NLRP3 inflammasome plays an essential role in the process of VR. Here, we reviewed the latest studies on the activation pathway of the NLRP3 inflammasome, focusing on the effects of the NLRP3 inflammasome in primary cells during VR, and finally discuss future research directions in this field.
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Affiliation(s)
- Zhipeng Yan
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China.,National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, China
| | - Zhongwen Qi
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Xiaoya Yang
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Nan Ji
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yueyao Wang
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Qi Shi
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Meng Li
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Junping Zhang
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
| | - Yaping Zhu
- Department of Cardiology, First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, China
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Su Y, Zhang Y, Hu Z, He L, Wang W, Xu J, Fan Z, Liu C, Zhang H, Zhao K. Prokineticin 2 via Calcium-Sensing Receptor Activated NLRP3 Inflammasome Pathway in the Testicular Macrophages of Uropathogenic Escherichia coli-Induced Orchitis. Front Immunol 2020; 11:570872. [PMID: 33193351 PMCID: PMC7644440 DOI: 10.3389/fimmu.2020.570872] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 09/02/2020] [Indexed: 12/27/2022] Open
Abstract
Reproductive tract infections contribute to the development of testicular inflammatory lesions, leading to male infertility. Previous research shows that the activation of the NLRP3 inflammasome in orchitis promotes the secretion and maturation of IL-1β and, thus, decreases male fertility. The calcium-sensing receptor (CaSR) is closely related to the secretion of proinflammatory cytokines. An increase in the CaSR level promotes the assembly and activation of the NLRP3 inflammasome. However, the role of CaSRs in orchitis is unknown. We first constructed a uropathogenic Escherichia Coli (UPEC) rat orchitis model and then detected the expression of CaSR and NLRP3 inflammatory pathway proteins in testicular macrophages (TM) through RT-PCR and WB, calcium levels in TM through flow cytometry, and proinflammatory factor IL-1β through ELISA. In addition, testosterone levels in the serum samples were detected using liquid chromatography–mass spectrometry (LC-MS). Here, we show that CaSR upregulation after infection in TM in a rat model of UPEC induces the activation of the NLRP3 inflammasome pathway and thereby enhances IL-1β secretion and reduces the testosterone level in the blood. Moreover, CaSR inhibitors can alleviate inflammatory impairment. After UPEC challenge in vitro, CaSR promoted NLRP3 expression and released IL-1β cleaved from TM into the supernatant. Overall, elevated CaSR levels in TM in testes with UPEC-induced orchitis may impair testosterone synthesis through the activation of the NLRP3 pathway and PK2 is an upstream regulatory protein of CaSR. Our research further shows the underlying mechanisms of inflammation-related male infertility and provides anti-inflammatory therapeutic targets for male infertility.
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Affiliation(s)
- Yufang Su
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yuan Zhang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhiyong Hu
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Liting He
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wei Wang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jia Xu
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zunpan Fan
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chunyan Liu
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Huiping Zhang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Kai Zhao
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Mattar P, Sanhueza S, Yuri G, Briones L, Perez-Leighton C, Rudich A, Lavandero S, Cifuentes M. Calcium-Sensing Receptor in Adipose Tissue: Possible Association with Obesity-Related Elevated Autophagy. Int J Mol Sci 2020; 21:E7617. [PMID: 33076271 PMCID: PMC7590196 DOI: 10.3390/ijms21207617] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/01/2020] [Accepted: 10/06/2020] [Indexed: 12/12/2022] Open
Abstract
Autophagy is upregulated in adipose tissue (AT) from people with obesity. We showed that activation of the calcium-sensing receptor (CaSR) elevates proinflammatory cytokines through autophagy in preadipocytes. Our aim is to understand the role of CaSR on autophagy in AT from humans with obesity. We determined mRNA and protein levels of CaSR and markers of autophagy by qPCR and western blot in human visceral AT explants or isolated primary preadipocytes (60 donors: 72% female, 23-56% body fat). We also investigated their association with donors' anthropometric variables. Donors' % body fat and CaSR mRNA expression in AT were correlated (r = 0.44, p < 0.01). CaSR expression was associated with mRNA levels of the autophagy markers atg5 (r = 0.37, p < 0.01), atg7 (r = 0.29, p < 0.05) and lc3b (r = 0.40, p < 0.01). CaSR activation increased becn and atg7 mRNA expression in AT. CaSR activation also upregulated LC3II by ~50%, an effect abolished by the CaSR inhibitor. Spermine (CaSR agonist) regulates LC3II through the ERK1/2 pathway. Structural equation model analysis suggests a link between donors' AT CaSR expression, AT autophagy and expression of Tumor Necrosis Factor alpha TNF-α. CaSR expression in visceral AT is directly associated with % body fat, and CaSR activation may contribute to obesity-related disruption in AT autophagy.
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Affiliation(s)
- Pamela Mattar
- Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago 7830490, Chile; (P.M.); (S.S.); (G.Y.); (L.B.)
| | - Sofía Sanhueza
- Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago 7830490, Chile; (P.M.); (S.S.); (G.Y.); (L.B.)
| | - Gabriela Yuri
- Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago 7830490, Chile; (P.M.); (S.S.); (G.Y.); (L.B.)
| | - Lautaro Briones
- Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago 7830490, Chile; (P.M.); (S.S.); (G.Y.); (L.B.)
- Department of Nutrition and Public Health, Faculty of Health Sciences, University of Bío-Bío, Andrés Bello 720, Chillán 3800708, Chile
| | - Claudio Perez-Leighton
- Department of Physiology, Faculty of Biological Sciences, Pontifical Catholic University of Chile, Santiago 3580000, Chile;
| | - Assaf Rudich
- Department of Clinical Biochemistry and Pharmacology, Ben-Gurion University of the Negev, Beer-Sheva 84103, Israel;
- The National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84103, Israel
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago 8380492, Chile;
- Center for Exercise, Metabolism and Cancer (CEMC), Faculty of Medicine, University of Chile, Santiago 8380492, Chile
- Department of Internal Medicine, Cardiology Division, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Mariana Cifuentes
- Institute of Nutrition and Food Technology (INTA), University of Chile, Santiago 7830490, Chile; (P.M.); (S.S.); (G.Y.); (L.B.)
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences & Faculty of Medicine, University of Chile, Santiago 8380492, Chile;
- Center for Exercise, Metabolism and Cancer (CEMC), Faculty of Medicine, University of Chile, Santiago 8380492, Chile
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