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Pergolizzi S, Fumia A, D'Angelo R, Mangano A, Lombardo GP, Giliberti A, Messina E, Alesci A, Lauriano ER. Expression and function of toll-like receptor 2 in vertebrate. Acta Histochem 2023; 125:152028. [PMID: 37075649 DOI: 10.1016/j.acthis.2023.152028] [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: 03/08/2023] [Revised: 04/13/2023] [Accepted: 04/13/2023] [Indexed: 04/21/2023]
Abstract
Toll-like receptors (TLRs) are essential for identifying and detecting pathogen-associated molecular patterns (PAMPs) produced by a variety of pathogens, including viruses and bacteria. Since TLR2 is the only TLR capable of creating functional heterodimers with more than two other TLR types, it is very important for vertebrate immunity. TLR2 not only broadens the variety of PAMPs that it can recognize but has also the potential to diversify the subsequent signaling cascades. TLR2 is ubiquitous, which is consistent with the wide variety of tasks and functions it serves. Immune cells, endothelial cells, and epithelial cells have all been found to express TLR2. This review aims to gather currently available information about the preservation of this intriguing immunological molecule in the phylum of vertebrates.
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Affiliation(s)
- Simona Pergolizzi
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Angelo Fumia
- Department of Clinical and Experimental Medicine, University of Messina, Padiglione C, A. O. U. Policlinico "G. Martino", 98124 Messina, Italy
| | - Roberta D'Angelo
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Angelica Mangano
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Giorgia Pia Lombardo
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Angelo Giliberti
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Emmanuele Messina
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Alessio Alesci
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy.
| | - Eugenia Rita Lauriano
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
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High Levels of Leptin and Adipsin Are Associated with Clinical Activity in Early Rheumatoid Arthritis Patients with Overweight and Periodontal Infection. Diagnostics (Basel) 2023; 13:diagnostics13061126. [PMID: 36980434 PMCID: PMC10047025 DOI: 10.3390/diagnostics13061126] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/14/2022] [Accepted: 12/19/2022] [Indexed: 03/18/2023] Open
Abstract
Adipokines are associated with the pathogenesis of rheumatoid arthritis (RA) and are potential biomarkers of disease activity, periodontitis, and obesity. The aim of this was to establish the association between adipokine profile, RA disease activity, body mass index, and periodontal infection. This study evaluated 51 patients with early-RA and 51 controls including serum rheumatological markers, adipokine levels, detection of Porphyromonas gingivalis and serum anti-Porphyromonas gingivalis antibodies, clinical and periodontal measurements. Statistical analyses were run with SPSS® V26, with a logistic regression model to confirm associations. The results show high levels of leptin were more frequent in patients (p = 0.001) who simultaneously showed a higher frequency of Porphyromonas gingivalis (p = 0.004). Patients with concomitant presence of Porphyromonas gingivalis, high clinical activity score, and overweight were correlated with high levels of leptin (OR, 7.20; 95% CI, 2.68–19.33; p = 0.0001) and adipsin (OR, 2.69; 95% CI, 1.00–7.28; p = 0.005). The conclusion is that high levels of leptin and adipsin are associated with greater clinical activity in early-RA patients with overweight and periodontal infection, whereby overweight and Porphyromonas gingivalis may enhance RA activity. This may represent a pathological mechanism between these conditions, where adipokines seem to have a key role.
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Abend Bardagi A, Dos Santos Paschoal C, Favero GG, Riccetto L, Alexandrino Dias ML, Guerra Junior G, Degasperi G. Leptin's Immune Action: A Review Beyond Satiety. Immunol Invest 2023; 52:117-133. [PMID: 36278927 DOI: 10.1080/08820139.2022.2129381] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The adipose tissue is an endocrine organ that secretes adipokines such as leptin, which is one of the most important hormones for controlling satiety, metabolism, and energy homeostasis. This hormone acts in the regulation of innate and adaptive immune responses since immune cells have leptin receptors from which this hormone initiates its biological action. These receptors have been identified in hematopoietic stem cells in the bone marrow and mature immune cells, inducing signaling pathways mediated by JAK/STAT, PI3K, and ERK 1/2. It is known that the bone marrow also contains leptin-producing adipocytes, which are crucial for regulating hematopoiesis through largely unknown mechanisms. Therefore, we have reviewed the roles of leptin inside and outside the bone marrow, going beyond its action in the control of satiety.
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Affiliation(s)
- Alice Abend Bardagi
- Center for Health Sciences, School of Medical Sciences, Pontifícia Universidade Católica de Campinas (PUC-Campinas), Campinas, Brazil
| | - Clarissa Dos Santos Paschoal
- Center for Health Sciences, School of Medical Sciences, Pontifícia Universidade Católica de Campinas (PUC-Campinas), Campinas, Brazil
| | - Giovanna Ganem Favero
- Center for Health Sciences, School of Medical Sciences, Pontifícia Universidade Católica de Campinas (PUC-Campinas), Campinas, Brazil
| | - Luisa Riccetto
- Center for Health Sciences, School of Medical Sciences, Pontifícia Universidade Católica de Campinas (PUC-Campinas), Campinas, Brazil
| | - Maria Luisa Alexandrino Dias
- Center for Health Sciences, School of Medical Sciences, Pontifícia Universidade Católica de Campinas (PUC-Campinas), Campinas, Brazil
| | - Gil Guerra Junior
- Center for Investigation in Pediatrics (CIPED), School of Medical Sciences, Universidade Estadual de Campinas (Unicamp), Campinas, Brazil
| | - Giovanna Degasperi
- Center for Health Sciences, School of Medical Sciences, Pontifícia Universidade Católica de Campinas (PUC-Campinas), Campinas, Brazil
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Abstract
Aging is associated with systemic inflammation and decreased production of protective antibodies while the production of autoimmune antibodies is increased. Our results have shown that the human obese adipose tissue (AT), which increases in size with aging, contributes to systemic and B cell intrinsic inflammation, reduced protective and increased pathogenic B cell responses leading to increased secretion of autoimmune antibodies. With this R56 funding, we have been able to investigate the cellular and molecular mechanisms by which the human obese AT induces intrinsic B cell inflammation and dysfunctional B cell responses, stimulates the secretion of autoimmune antibodies, whose specificity has been characterized, and engages different AT cell types in antigen presentation pathways to allow secretion of these autoimmune antibodies. Briefly, immune cells are recruited to the AT by chemokines released by both non-immune (adipocytes) and by resident and infiltrating immune cells. We have identified several mechanisms responsible for the release of “self” antigens, and we have shown that reduced oxygen availability and hypoxia, cell cytotoxicity and DNA damage induce cell death and lead to further release of pro-inflammatory cytokines, “self” protein antigens, cell-free DNA and lipids. We have also identified different antigen presenting cells in the AT, responsible for the activation of pathogenic B cells, class switch and secretion of autoimmune IgG antibodies. The experiments performed have allowed the discovery of novel mechanisms for pathogenic responses and the identification of pathways to target in order to promote better humoral immunity during aging.
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Fuseini H, Smith R, Nochowicz CH, Simmons JD, Hannah L, Wanjalla CN, Gabriel CL, Mashayekhi M, Bailin SS, Castilho JL, Hasty AH, Koethe JR, Kalams SA. Leptin Promotes Greater Ki67 Expression in CD4 + T Cells From Obese Compared to Lean Persons Living With HIV. Front Immunol 2022; 12:796898. [PMID: 35111163 PMCID: PMC8801429 DOI: 10.3389/fimmu.2021.796898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 12/16/2021] [Indexed: 11/13/2022] Open
Abstract
While antiretroviral therapy (ART) has proven effective in suppressing viremia and disease progression among people living with human immunodeficiency virus (HIV; PLWH), suboptimal CD4+ T cell reconstitution remains a major obstacle in nearly 30% of ART-treated individuals. Epidemiological studies demonstrate that obesity, or a body mass index (BMI) ≥ 30 kg/m2, is positively correlated with greater CD4+ T cell recovery in PLWH on ART. Leptin is a known immunomodulator that is produced in proportion to fat mass and is increased in obese individuals, including PLWH. We hypothesized that CD4+ T cells from obese PLWH have increased cell proliferation and cytokine production compared to cells from lean PLWH, potentially modulated by differential effects of leptin signaling. To test this hypothesis, peripheral blood mononuclear cells from obese and lean PLWH with long-term virologic suppression on the same ART regimen were pretreated with recombinant leptin and then stimulated with anti-CD3/CD28 or PMA/ionomycin to measure Ki67 expression, leptin receptor (LepR) surface expression and cytokine production. In the absence of leptin, Ki67 expression and IL-17A production were significantly higher in CD4+ T cells from obese compared to lean PLWH. However, LepR expression was significantly lower on CD4+ T cells from obese compared to lean PLWH. After leptin treatment, Ki67 expression was significantly increased in CD4+ T cells from obese PLWH compared to the lean participants. Leptin also increased IL-17A production in CD4+ T cells from obese healthy controls. In contrast, leptin decreased IL-17A production in CD4+ T cells from both obese and lean PLWH. Combined, these results demonstrate that obesity is associated with greater CD4+ T cell proliferation among PLWH, and that higher circulating leptin levels in obesity may contribute to improved CD4+ T reconstitution in PLWH initiating ART.
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Affiliation(s)
- Hubaida Fuseini
- Divison of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Rita Smith
- Tennessee Center for AIDS Research, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Cindy H. Nochowicz
- Tennessee Center for AIDS Research, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Joshua D. Simmons
- Tennessee Center for AIDS Research, Vanderbilt University Medical Center, Nashville, TN, United States
| | - LaToya Hannah
- Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Celestine N. Wanjalla
- Divison of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
- Tennessee Center for AIDS Research, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Curtis L. Gabriel
- Tennessee Center for AIDS Research, Vanderbilt University Medical Center, Nashville, TN, United States
- Division of Gastroenterology, Hepatology and Nutrition, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Mona Mashayekhi
- Division of Diabetes, Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Samuel S. Bailin
- Divison of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Jessica L. Castilho
- Divison of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Alyssa H. Hasty
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, United States
- The Veterans Affairs Tennessee Healthcare System, Nashville, TN, United States
| | - John R. Koethe
- Divison of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
- Tennessee Center for AIDS Research, Vanderbilt University Medical Center, Nashville, TN, United States
- The Veterans Affairs Tennessee Healthcare System, Nashville, TN, United States
| | - Spyros A. Kalams
- Divison of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, United States
- Tennessee Center for AIDS Research, Vanderbilt University Medical Center, Nashville, TN, United States
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6
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Wang PH, Wu MF, Hsu CY, Pan SW, Shu CC, Cheng SL. The Trend of TIM3 Expression on T Cells in Patients With Nontuberculous Mycobacterial Lung Disease: From Immune Cell Dysfunction to Clinical Severity. Front Immunol 2021; 12:738056. [PMID: 34867961 PMCID: PMC8636047 DOI: 10.3389/fimmu.2021.738056] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/19/2021] [Indexed: 12/26/2022] Open
Abstract
Background The incidence of nontuberculous mycobacterial lung disease (NTM-LD) is increasing worldwide. Immune exhaustion has been reported in NTM-LD, but T-cell immunoglobulin and mucin domain-containing protein 3 (TIM3), a co-inhibitory receptor on T cells, has been scarcely studied. Methods Patients with NTM-LD and healthy controls were prospectively recruited from July 2014 to August 2019 at three tertiary referral centers in Taiwan. We examined TIM3 expression on the T cells from the participants using flow cytometry. TIM3 expression was analyzed for different disease statuses and after treatment. The apoptosis and cytokine profiles were analyzed according to the TIM3 expression. Results Among enrolled subjects (47 patients and 46 controls), TIM3 on CD4+ cells (6.44% vs. 4.12%, p = 0.028) and CD8+ cells (18.47% vs. 9.13%, p = 0.003) were higher in NTM-LD patients than in the controls. The TIM3 level on CD4+ and CD8+ T cells was positively associated with T-cell apoptosis in the NTM-LD patients. In stimulating peripheral blood mononuclear cells using PMA plus ionomycin, a high TIM3 level on T cells correlated with low interleukin-2 and tumor necrosis factor-alpha (TNF-α) on CD4+ cells and interferon-gamma and TNF-α on CD8+ T cells. For clinical manifestation, low body mass index (BMI), positive sputum acid-fast smear, and high radiographic score correlated with high TIM3 expression on T cells. After NTM treatment, TIM3+ decreased significantly on CD4+ and CD8+ T cells. Conclusions In patients with NTM-LD, TIM3+ expression increased over CD4+ and CD8+ T cells and correlated with cell apoptosis and specific cytokine attenuation. Clinically, TIM3+ T cells increased in patients with low BMI, high disease extent, and high bacilli burden but decreased after treatment.
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Affiliation(s)
- Ping-Huai Wang
- Division of Pulmonology, Department of Internal Medicine, Far Eastern Memorial Hospital, New Taipei City, Taiwan
| | - Ming-Fang Wu
- Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan.,Institute of Statistical Sciences, Academia Sinica, Taipei, Taiwan
| | - Chi-Yu Hsu
- College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Sheng-Wei Pan
- Department of Chest Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chin-Chung Shu
- College of Medicine, National Taiwan University, Taipei, Taiwan.,Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Shih-Lung Cheng
- Division of Pulmonology, Department of Internal Medicine, Far Eastern Memorial Hospital, New Taipei City, Taiwan.,Department of Chemical Engineering and Materials Science, Yuan Ze University, Taoyuan City, Taiwan
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7
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Santos E Silva JC, Vasconcelos AP, Noma IHY, Noronha NY, Aquino R, Giddaluru J, Durão L, Costa-Martins AG, Schuch V, Moraes-Vieira PM, Nakaya HI. Gene signatures of autopsy lungs from obese patients with COVID-19. Clin Nutr ESPEN 2021; 44:475-478. [PMID: 34330510 PMCID: PMC8149170 DOI: 10.1016/j.clnesp.2021.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 05/05/2021] [Indexed: 01/27/2023]
Abstract
Background & aims Obesity is associated with low grade systemic inflammation and insulin resistance. Although metabolic and immunological changes may contribute to the increased risk for COVID-19 mortality in obese, little is known about the impact of obesity in the lungs of patients with COVID-19. Methods We analyzed gene expression profiles of autopsy lungs of a cohort of 14 COVID-19 patients and 4 control individuals. Patients were divided into 3 groups according to their comorbidities: hypertension, type 2 diabetes (T2D) and obesity. We then identified the molecular alterations associated with these comorbidities in COVID-19 patients. Results Patients with only hypertension showed higher levels of inflammatory genes and B-cell related genes when compared to those with T2D and obesity. However, the levels of IFN-gamma, IL22, and CD274 (a ligand that binds to receptor PD1) were higher in COVID-19 patients with T2D and obesity. Several metabolic- and immune-associated genes such as G6PD, LCK and IL10 were significantly induced in the lungs of the obese group. Conclusion Our findings suggest that SARS-CoV-2 infection in the lungs may exacerbate the immune response and chronic condition in obese COVID-19 patients.
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Affiliation(s)
- Juan Carlo Santos E Silva
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Amanda Pereira Vasconcelos
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Isabella Harumi Yonehara Noma
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Natália Yumi Noronha
- Department of Internal Medicine, Ribeirão Preto Medical School, University of São Paulo, Brazil
| | - Rodrigo Aquino
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Jeevan Giddaluru
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil; Scientific Platform Pasteur-University of São Paulo, São Paulo, Brazil
| | - Luiz Durão
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - André Guilherme Costa-Martins
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil; Scientific Platform Pasteur-University of São Paulo, São Paulo, Brazil
| | - Viviane Schuch
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Pedro M Moraes-Vieira
- Laboratory of Immunometabolism, Department of Genetics, Evolution, Microbiology and Immunology, Institute of Biology, University of Campinas, Brazil; Obesity and Comorbidities Research Center (OCRC), University of Campinas, Campinas, São Paulo, Brazil
| | - Helder I Nakaya
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil; Scientific Platform Pasteur-University of São Paulo, São Paulo, Brazil.
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Fuseini H, Gyan BA, Kyei GB, Heimburger DC, Koethe JR. Undernutrition and HIV Infection in Sub-Saharan Africa: Health Outcomes and Therapeutic Interventions. Curr HIV/AIDS Rep 2021; 18:87-97. [PMID: 33606196 PMCID: PMC8404370 DOI: 10.1007/s11904-021-00541-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2021] [Indexed: 12/14/2022]
Abstract
PURPOSE OF REVIEW Sub-Saharan Africa (SSA) is disproportionately burdened by the twin epidemics of food insecurity and HIV infection, and protein-calorie undernutrition is common among persons with HIV (PWH) initiating antiretroviral therapy (ART) in the region. In this review, we discuss the intersection of HIV infection and undernutrition, health outcomes among undernourished PWH starting ART, and the demonstrated and potential benefits of therapeutic interventions such as micro/macronutrient supplementation and pharmacological agents. RECENT FINDINGS A low body mass index (BMI), used as a general indicator of poor nutrition in most studies, is associated with impaired immune recovery and increased mortality in the early ART period. The increased risk of mortality is multifactorial, and contributors include undernutrition-related immune system dysfunction, increased susceptibility to opportunistic infections, and metabolic and cardiovascular dysregulation. Clinical trials of micro/macronutrient supplementary feeding, appetite stimulants (hormones and anabolic agents), and recombinant adipokines have shown a benefit for weight gain and metabolic health, but there are few data on mortality or immune recovery. A substantial proportion of PWH in SSA are undernourished, and undernutrition contributes to an increased risk of mortality and other adverse health outcomes. To date, there have been few prospective trials of nutritional supplementation and/or pharmacologic therapy among undernourished PWH in SSA, though findings from other settings suggest a potential benefit in this population.
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Affiliation(s)
- Hubaida Fuseini
- Department of Immunology, Noguchi Memorial Institute for Medical Research, Legon, Ghana.
- Department of Virology, Noguchi Memorial Institute for Medical Research, Legon, Ghana.
- Divison of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, 37232-2582, USA.
| | - Ben A Gyan
- Department of Immunology, Noguchi Memorial Institute for Medical Research, Legon, Ghana
- Department of Virology, Noguchi Memorial Institute for Medical Research, Legon, Ghana
| | - George B Kyei
- Department of Immunology, Noguchi Memorial Institute for Medical Research, Legon, Ghana
- Department of Virology, Noguchi Memorial Institute for Medical Research, Legon, Ghana
- Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO, USA
| | | | - John R Koethe
- Divison of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, 37232-2582, USA
- Vanderbilt Institute for Global Health, Nashville, TN, USA
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Kiernan K, MacIver NJ. The Role of the Adipokine Leptin in Immune Cell Function in Health and Disease. Front Immunol 2021; 11:622468. [PMID: 33584724 PMCID: PMC7878386 DOI: 10.3389/fimmu.2020.622468] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 12/14/2020] [Indexed: 12/20/2022] Open
Abstract
Leptin is a critical mediator of the immune response to changes in overall nutrition. Leptin is produced by adipocytes in proportion to adipose tissue mass and is therefore increased in obesity. Despite having a well-described role in regulating systemic metabolism and appetite, leptin displays pleiotropic actions, and it is now clear that leptin has a key role in influencing immune cell function. Indeed, many immune cells have been shown to respond to leptin directly via the leptin receptor, resulting in a largely pro-inflammatory phenotype. Understanding the role of adipose-tissue derived mediators in inflammation is critical to determining the pathophysiology of multiple obesity-associated diseases, such as type 2 diabetes, autoimmune disease, and infection. This review, therefore, focuses on the latest data regarding the role of leptin in modulating inflammation.
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Affiliation(s)
- Kaitlin Kiernan
- Department of Immunology, Duke University School of Medicine, Durham, NC, United States
| | - Nancie J. MacIver
- Department of Immunology, Duke University School of Medicine, Durham, NC, United States
- Department of Pediatrics, Duke University School of Medicine, Durham, NC, United States
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC, United States
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10
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Wang J, Xu Y, Zhang X, Wang S, Peng Z, Guo J, Jiang H, Liu J, Xie Y, Wang J, Li X, Liao J, Wan C, Yu L, Hu J, Liu B, Liu Z. Leptin correlates with monocytes activation and severe condition in COVID-19 patients. J Leukoc Biol 2021; 110:9-20. [PMID: 33404078 DOI: 10.1002/jlb.5hi1020-704r] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/23/2020] [Accepted: 12/07/2020] [Indexed: 12/15/2022] Open
Abstract
Excessive monocyte activation with the development of excessive or uncontrolled release of proinflammatory cytokines often results in host tissue injury and even death in patients with pneumonia caused by the 2019 novel coronavirus. However, the changes of cytokine profiles of coronavirus disease 2019 (COVID-19) patients, as well as the underlying mechanisms that are involved, remain unknown. Using a cytokine array containing 174 inflammation-related cytokines, we found significantly altered cytokine profiles in severe COVID-19 patients compared with those in mild patients or healthy controls, and identified leptin, CXCL-10, IL-6, IL-10, IL-12, and TNF-α as the top differentially expressed cytokines. Notably, leptin showed high consistency with CXCL-10 and TNF-α in predicting disease severity, and correlated with body mass index, decreased lymphocyte counts, and disease progression. Further analysis demonstrated that monocytes in severe patients with higher leptin levels were inclined toward M1 polarization. Mechanistic studies revealed that leptin synergistically up-regulated expression levels of inflammatory cytokines and surface markers with IL-6 in monocytes through STAT3 and NF-κB signaling pathways. Collectively, our results suggest that overweight COVID-19 patients were prone to have higher leptin levels, which further activated monocytes, resulting in amplified or dysregulated immune responses. Taken together, our findings argue that leptin correlates severity of COVID-19 and may indicate a possible mechanism by which overweight patients have a greater tendency to develop severe conditions.
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Affiliation(s)
- Jingya Wang
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Yinyin Xu
- Clinical Laboratory of Yongchuan Hospital, Chongqing Medical University, Chongqing, Chongqing, China.,Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, Chongqing, China
| | - Xiaoli Zhang
- Clinical Laboratory of Yongchuan Hospital, Chongqing Medical University, Chongqing, Chongqing, China.,Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, Chongqing, China
| | - Sheng Wang
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Ziyi Peng
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Jing Guo
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Hongmei Jiang
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Jing Liu
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Ying Xie
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Jingjing Wang
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Xin Li
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
| | - Juan Liao
- Clinical Laboratory of Yongchuan Hospital, Chongqing Medical University, Chongqing, Chongqing, China.,Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, Chongqing, China
| | - Chao Wan
- Clinical Laboratory of Yongchuan Hospital, Chongqing Medical University, Chongqing, Chongqing, China.,Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, Chongqing, China
| | - Lihua Yu
- Clinical Laboratory of Yongchuan Hospital, Chongqing Medical University, Chongqing, Chongqing, China.,Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, Chongqing, China
| | - Jinsong Hu
- Department of Cell Biology and Genetics, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China.,The Institute of Infection and Immunity, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, China
| | - Beizhong Liu
- Clinical Laboratory of Yongchuan Hospital, Chongqing Medical University, Chongqing, Chongqing, China.,Key Laboratory of Laboratory Medical Diagnostics, Ministry of Education, Department of Laboratory Medicine, Chongqing Medical University, Chongqing, Chongqing, China
| | - Zhiqiang Liu
- Tianjin Key Laboratory of Cellular Homeostasis and Human Diseases, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China.,Department of Physiology and Pathophysiology, School of Basic Medical Science, Tianjin Medical University, Heping, Tianjin, China
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11
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Photoperiod Affects Leptin Action on the Choroid Plexus in Ewes Challenged with Lipopolysaccharide-Study on the mRNA Level. Int J Mol Sci 2020; 21:ijms21207647. [PMID: 33076568 PMCID: PMC7589540 DOI: 10.3390/ijms21207647] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/05/2020] [Accepted: 10/12/2020] [Indexed: 12/22/2022] Open
Abstract
The ovine choroid plexus (ChP) expresses the long isoform of the leptin receptor, which makes this structure a potential target for leptin action. In sheep, leptin concentration in plasma is higher during long days (LD) than short days (SD). This study evaluates the influence a of photoperiod on leptin impact on the gene expression of Toll-like receptor 4 (TLR4), proinflammatory cytokines (IL1B, IL6), their receptors (IL1R1, IL1R2, ILRN, IL6R, IL6ST) and inflammasome components necessary for pro-IL-1β activation (NLRP3, PYCARD, CASP1), chemokine (CCL2), leptin receptor isoforms (LEPRa, LEPRb) and a suppressor of cytokine signalling (SOCS3) in the ChP of ewes treated or not with lipopolysaccharide (LPS). Studies were conducted on adult female sheep divided into four groups (n = 6 in each): control, leptin (20 μg/kg), LPS (400 ng/kg), and LPS and leptin injected under SD and LD photoperiods. The leptin alone did not affect the gene expression but in co-treatment with LPS increased (p < 0.05) IL1B but only during SD, and SOCS3, IL1R2, IL1RN, IL6ST and CCL2 only during LD, and decreased (p < 0.05) the IL1R1 expression only during SD photoperiod. This indicates that the immunomodulatory action of leptin on the ChP is manifested only under the LPS challenge and is photoperiodically dependent.
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12
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Yadav NVS, Barcikowski A, Uehana Y, Jacobs AT, Connelly L. Breast Adipocyte Co-culture Increases the Expression of Pro-angiogenic Factors in Macrophages. Front Oncol 2020; 10:454. [PMID: 32318345 PMCID: PMC7154118 DOI: 10.3389/fonc.2020.00454] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 03/13/2020] [Indexed: 01/31/2023] Open
Abstract
Obese individuals with breast cancer have a poorer prognosis and higher risk of metastatic disease vs. non-obese patients. Adipose tissue in obese individuals is characterized by an enhanced macrophage infiltration, creating a microenvironment that favors tumor progression. Here, we demonstrate a role for adipocyte-macrophage interactions in the regulation of angiogenesis. Co-culture of THP-1 macrophages with human breast adipocytes led to increased expression of the pro-angiogenic growth factor, vascular endothelial growth factor A (VEGFA). Several adipocyte-derived proteins including leptin, insulin, IL-6, and TNF-α were each capable of increasing VEGFA expression in THP-1 macrophages, identifying these as possible mediators of the changes that were observed with co-culture. Furthermore, analysis of THP-1 culture media by antibody array revealed that THP-1 secrete several other pro-angiogenic signals in response to adipocyte co-culture, including interleukin 8 (IL-8), matrix metalloproteinase 9 (MMP9), pentraxin 3 (PTX3), and serpin E1 (plasminogen activator inhibitor 1, PAI1) after co-culture with human adipocytes. We used an in vitro endothelial tube formation assay with human vascular endothelial cells to evaluate the effects of THP-1 culture media on angiogenesis. Here, culture media from THP-1 cells previously exposed to human adipocytes stimulated endothelial tube formation more significantly than THP-1 cells cultured alone. In summary, we find that adipocyte co-culture stimulates the expression of pro-angiogenic mediators in macrophages and has pro-angiogenic effects in vitro, thus representing a possible mechanism for the enhanced risk of breast cancer progression in obese individuals.
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Affiliation(s)
- Nalini V. S. Yadav
- Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy, University of Hawaii at Hilo, Hilo, HI, United States
| | - Arthur Barcikowski
- Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy, University of Hawaii at Hilo, Hilo, HI, United States
| | - Yuko Uehana
- Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy, University of Hawaii at Hilo, Hilo, HI, United States
| | - Aaron T. Jacobs
- School of Medicine, California University of Science and Medicine, San Bernardino, CA, United States
| | - Linda Connelly
- School of Medicine, California University of Science and Medicine, San Bernardino, CA, United States
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13
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Cooper DM, Radom-Aizik S. Exercise-associated prevention of adult cardiovascular disease in children and adolescents: monocytes, molecular mechanisms, and a call for discovery. Pediatr Res 2020; 87:309-318. [PMID: 31649340 PMCID: PMC11177628 DOI: 10.1038/s41390-019-0581-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 08/07/2019] [Accepted: 08/15/2019] [Indexed: 12/28/2022]
Abstract
Atherosclerosis originates in childhood and adolescence. The goal of this review is to highlight how exercise and physical activity during childhood and adolescence, critical periods of growth and development, can prevent adult cardiovascular disease (CVD), particularly through molecular mechanisms of monocytes, a key cell of the innate immune system. Monocytes are heterogeneous and pluripotential cells that can, paradoxically, play a role in both the instigation and prevention of atherosclerosis. Recent discoveries in young adults reveal that brief exercise affects monocyte gene pathways promoting a cell phenotype that patrols the vascular system and repairs injuries. Concurrently, exercise inhibits pro-inflammatory monocytes, cells that contribute to vascular damage and plaque formation. Because CVD is typically asymptomatic in youth, minimally invasive techniques must be honed to study the subtle anatomic and physiologic evidence of vascular dysfunction. Exercise gas exchange and heart rate measures can be combined with ultrasound assessments of vascular anatomy and reactivity, and near-infrared spectroscopy to quantify impaired O2 transport that is often hidden at rest. Combined with functional, transcriptomic, and epigenetic monocyte expression and measures of monocyte-endothelium interaction, molecular mechanisms of early CVD can be formulated, and then translated into effective physical activity-based strategies in youth to prevent adult-onset CVD.
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Affiliation(s)
- Dan M Cooper
- Pediatric Exercise and Genomics Research Center, University of California Irvine School of Medicine, Pediatrics, Irvine, CA, USA.
| | - Shlomit Radom-Aizik
- Pediatric Exercise and Genomics Research Center, University of California Irvine School of Medicine, Pediatrics, Irvine, CA, USA
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14
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Leptin: an unappreciated key player in SLE. Clin Rheumatol 2019; 39:305-317. [PMID: 31707542 DOI: 10.1007/s10067-019-04831-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/18/2019] [Accepted: 10/23/2019] [Indexed: 02/08/2023]
Abstract
Leptin is the forerunner of the adipokine superfamily and plays a key role in regulating energy expenditure and neuroendocrine function. Researches into leptin put emphasize not only on the metabolic role but also its immunoregulatory effect on immune response through immunocyte activation and cytokine secretion. Leptin acts on receptors that are widespread throughout the body and that are expressed across many tissue types. As a consequence, the abnormal expression of leptin has been found to correlate with a number of diseases, including cancers, autoimmune diseases, and cardiovascular diseases. The significance of leptin in the development of autoimmune diseases is becoming increasingly prominent. Systemic lupus erythematosus (SLE) is a severe atypical autoimmune disease that causes damage to multiple organ systems. It is characterised by the following: impaired clearance of apoptotic cells, loss of tolerance to self-antigens, aberrant activation of T cells and B cells, and chronic inflammation. The heightened immunocyte response in SLE means that these physiological systems are particularly vulnerable to regulation by leptin in addition to being of great significance to the research field. Our current review provides insight into the regulatory roles that leptin plays on immune effector cells in SLE.
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15
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Frasca D, Diaz A, Romero M, Blomberg BB. Leptin induces immunosenescence in human B cells. Cell Immunol 2019; 348:103994. [PMID: 31831137 DOI: 10.1016/j.cellimm.2019.103994] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/14/2019] [Accepted: 10/15/2019] [Indexed: 11/16/2022]
Abstract
Leptin is an adipokine secreted primarily by the adipocytes. Leptin has endocrine and immune functions and increases the secretion of pro-inflammatory cytokines by immune cells. Here we show that incubation of B cells from young lean individuals with leptin increases the frequencies of pro-inflammatory B cells and induces intrinsic B cell inflammation, characterized by mRNA expression of pro-inflammatory cytokines (TNF-α and IL-6), chemokines (IL-8), micro-RNAs (miR-155 and miR-16), TLR4 and p16, a cell cycle regulator associated with immunosenescence. We have previously shown that the expression of these pro-inflammatory markers in unstimulated B cells is negatively associated with the response of the same B cells after in vivo or in vitro stimulation. B cells from young lean individuals, after in vitro incubation with leptin, show reduced class switch and influenza vaccine-specific IgG production. Our results altogether show that leptin makes B cells from youn lean individuals similar to those from young obese and elderly lean individuals, suggesting that leptin may be a mechanisms of immunosenescence in human B cells.
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Affiliation(s)
- Daniela Frasca
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL, USA.
| | - Alain Diaz
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Maria Romero
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Bonnie B Blomberg
- Department of Microbiology and Immunology, University of Miami Miller School of Medicine, Miami, FL, USA; Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USA
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16
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Liu Y, Gu Y, Shen Y, Lin B, Li Y, He X, Zhang Y, Lu L, Shen W, Zhang Q, Yang K. Association Between Serum Leptin Level and Calcific Aortic Valve Disease. J Am Heart Assoc 2019; 8:e012495. [PMID: 31566104 PMCID: PMC6806045 DOI: 10.1161/jaha.119.012495] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Background The pathophysiological process of calcific aortic valve disease (CAVD) is similar to that of atherosclerosis. Leptin accelerates the process of atherosclerosis. We sought to examine the relationship between leptin and CAVD. Methods and Results Serum leptin was measured in 397 consecutive patients undergoing standard transthoracic echocardiography and Doppler flow imaging. Multiple logistic regression analyses were used to assess the association between leptin and CAVD. Western blotting was performed to detect the expression of phosphorylated and total extracellular signal-regulated kinase. Serum leptin (median) was higher in 200 patients with CAVD than that in 197 non-CAVD controls (20.07 versus 9.03 ng/mL; P<0.01). Leptin correlated positively with age (r=0.37, P<0.01) and negatively with estimated glomerular filtration rate (r=-0.37, P<0.01). Multivariate analysis indicated that elevated leptin was an independent determinant for the presence of CAVD (P<0.01). Receiver-operating characteristic curve analysis of leptin to detect the presence of CAVD showed that the area under the curve was 0.74 (95% CI, 0.69-0.79; P<0.01). The diagnostic value of leptin for the detection of CAVD was higher among younger patients (aged ≤65 years) or those with at least mildly reduced renal function (estimated glomerular filtration rate ≤82.06 mL/min per 1.73 m2). The activation of extracellular signal-regulated kinase 1/2 was stronger in calcific aortic valves than in normal aortic valves. Conclusions Elevated leptin is associated with the presence of CAVD, especially among younger patients or those with renal dysfunction.
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Affiliation(s)
- Yehong Liu
- Department of Cardiology Shanghai East Hospital Shanghai Tongji University School of Medicine Shanghai China
| | - Yuying Gu
- Department of Cardiology Shanghai East Hospital Shanghai Tongji University School of Medicine Shanghai China
| | - Ying Shen
- Department of Cardiology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China
| | - Bowen Lin
- Department of Cardiology Shanghai East Hospital Shanghai Tongji University School of Medicine Shanghai China
| | - Ying Li
- Department of Cardiology Shanghai East Hospital Shanghai Tongji University School of Medicine Shanghai China
| | - Xiaoyan He
- Department of Cardiology Shanghai East Hospital Shanghai Tongji University School of Medicine Shanghai China
| | - Yibo Zhang
- Institute of Cardiovascular Disease Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China
| | - Lin Lu
- Institute of Cardiovascular Disease Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China.,Department of Cardiology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China
| | - Weifeng Shen
- Department of Cardiology Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China
| | - Qi Zhang
- Department of Cardiology Shanghai East Hospital Shanghai Tongji University School of Medicine Shanghai China
| | - Ke Yang
- Institute of Cardiovascular Disease Ruijin Hospital Shanghai Jiaotong University School of Medicine Shanghai China
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17
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Żółkiewicz J, Stochmal A, Rudnicka L. The role of adipokines in systemic sclerosis: a missing link? Arch Dermatol Res 2019; 311:251-263. [PMID: 30806766 PMCID: PMC6469644 DOI: 10.1007/s00403-019-01893-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 12/27/2018] [Accepted: 02/12/2019] [Indexed: 12/28/2022]
Abstract
Systemic sclerosis is a multiorgan autoimmune disease characterized by vasculopathy and tissue fibrosis of unknown etiology. Recently, adipokines (cell signaling proteins secreted by adipose tissue) have attracted much attention as a cytokine family contributing to the various pathological processes of systemic sclerosis. Adipokines, such as leptin, adiponectin, resistin, adipsin, visfatin or chemerin are a heterogenic group of molecules. Adiponectin exhibits anti-fibrotic features and affects inflammatory reactions. Leptin promotes fibrosis and inflammation. Resistin was linked to vascular involvement in systemic sclerosis. Visfatin was associated with regression of skin lesions in late-stage systemic sclerosis. Chemerin appears as a marker of increased risk of impaired renal function and development of skin sclerosis in the early stage of systemic sclerosis. Vaspin was indicated to have a protective role in digital ulcers development. Novel adipokines-adipsin, apelin, omentin and CTRP-3-are emerging as molecules potentially involved in SSc pathogenesis. Serum adipokine levels may be used as predictive and diagnostic factors in systemic sclerosis. However, further investigations are required to establish firm correlations between distinct adipokines and systemic sclerosis.
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Affiliation(s)
- Jakub Żółkiewicz
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warszawa, Poland
| | - Anna Stochmal
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warszawa, Poland
| | - Lidia Rudnicka
- Department of Dermatology, Medical University of Warsaw, Koszykowa 82A, 02-008, Warszawa, Poland.
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18
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Haruna T, Kariya S, Fujiwara T, Yuta A, Higaki T, Zhao P, Ogawa Y, Kanai K, Hirata Y, Oka A, Nishizaki K, Okano M. Role of whole saliva in the efficacy of sublingual immunotherapy in seasonal allergic rhinitis. Allergol Int 2019; 68:82-89. [PMID: 30166059 DOI: 10.1016/j.alit.2018.07.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 07/08/2018] [Accepted: 07/24/2018] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND The development of methods to predict the clinical effectiveness of sublingual immunotherapy (SLIT) for allergic diseases is a crucial matter. We sought to determine whether whole saliva, which is the first body component that contacts allergen extracts during SLIT, is associated with the clinical effectiveness of SLIT in Japanese cedar pollinosis. METHODS Blood monocytes or monocytic THP-1 cells were cultured in the presence or absence of either whole saliva or pure saliva with or without treatments including filtration and blockade of TLR2 and/or TLR4 signaling. IL-10 levels in the supernatants were then measured. Whole saliva-induced IL-10 production by THP-1 cells was compared between asymptomatic and disease-onset patients during peak pollen dispersal after SLIT. RESULTS Both monocytes and THP-1 cells produced substantial amounts of IL-10 in response to whole saliva. IL-10 production was significantly reduced in response to pure saliva and 0.2 μm-filtered saliva. Simultaneous treatment with polymyxin B and TL2.1, a neutralizing antibody against TLR2, also reduced IL-10 production. IL-10 levels produced by THP-1 cells in response to whole saliva collected prior to SLIT were significantly higher in asymptomatic patients determined by symptom-medication scores than disease-onset patients following SLIT. Such differences were not seen in saliva collected 3 months after the initiation of SLIT or saliva collected during peak pollen dispersal. CONCLUSIONS Our results provide a basis for why the sublingual route is effective and preferable in allergen immunotherapy. Saliva-induced IL-10 levels produced by THP-1 cells may be a predictive marker for clinical remission after SLIT.
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Affiliation(s)
- Takenori Haruna
- Department of Otolaryngology-Head & Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Shin Kariya
- Department of Otolaryngology-Head & Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Tazuko Fujiwara
- Department of Otolaryngology-Head & Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | | | - Takaya Higaki
- Department of Otolaryngology-Head & Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Pengfei Zhao
- Department of Otolaryngology-Head & Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | | | - Kengo Kanai
- Department Otorhinolaryngology-Head & Neck Surgery, Kagawa Prefectural Central Hospital, Takamatsu, Japan
| | - Yuji Hirata
- Department Otorhinolaryngology-Head & Neck Surgery, Kagawa Prefectural Central Hospital, Takamatsu, Japan
| | - Aiko Oka
- Department of Otolaryngology-Head & Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Kazunori Nishizaki
- Department of Otolaryngology-Head & Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
| | - Mitsuhiro Okano
- Department of Otolaryngology-Head & Neck Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan; Department of Otorhinolaryngology, International University of Health and Welfare School of Medicine, Narita, Japan.
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19
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Francisco V, Pino J, Campos-Cabaleiro V, Ruiz-Fernández C, Mera A, Gonzalez-Gay MA, Gómez R, Gualillo O. Obesity, Fat Mass and Immune System: Role for Leptin. Front Physiol 2018; 9:640. [PMID: 29910742 PMCID: PMC5992476 DOI: 10.3389/fphys.2018.00640] [Citation(s) in RCA: 240] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 05/11/2018] [Indexed: 12/13/2022] Open
Abstract
Obesity is an epidemic disease characterized by chronic low-grade inflammation associated with a dysfunctional fat mass. Adipose tissue is now considered an extremely active endocrine organ that secretes cytokine-like hormones, called adipokines, either pro- or anti-inflammatory factors bridging metabolism to the immune system. Leptin is historically one of most relevant adipokines, with important physiological roles in the central control of energy metabolism and in the regulation of metabolism-immune system interplay, being a cornerstone of the emerging field of immunometabolism. Indeed, leptin receptor is expressed throughout the immune system and leptin has been shown to regulate both innate and adaptive immune responses. This review discusses the latest data regarding the role of leptin as a mediator of immune system and metabolism, with particular emphasis on its effects on obesity-associated metabolic disorders and autoimmune and/or inflammatory rheumatic diseases.
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Affiliation(s)
- Vera Francisco
- The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Servizo Galego de Saude and Instituto de Investigación Sanitaria de Santiago, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Jesús Pino
- The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Servizo Galego de Saude and Instituto de Investigación Sanitaria de Santiago, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Victor Campos-Cabaleiro
- The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Servizo Galego de Saude and Instituto de Investigación Sanitaria de Santiago, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Clara Ruiz-Fernández
- The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Servizo Galego de Saude and Instituto de Investigación Sanitaria de Santiago, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Antonio Mera
- Servizo Galego de Saude, Division of Rheumatology, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Miguel A Gonzalez-Gay
- Epidemiology, Genetics and Atherosclerosis Research Group on Systemic Inflammatory Diseases, Hospital Universitario Marqués de Valdecilla, Universidad de Cantabria and IDIVAL, Santander, Spain
| | - Rodolfo Gómez
- Musculoskeletal Pathology Group, Servizo Galego de Saude and Instituto de Investigación Sanitaria de Santiago, Santiago University Clinical Hospital, Santiago de Compostela, Spain
| | - Oreste Gualillo
- The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Servizo Galego de Saude and Instituto de Investigación Sanitaria de Santiago, Santiago University Clinical Hospital, Santiago de Compostela, Spain
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20
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Alti D, Sambamurthy C, Kalangi SK. Emergence of Leptin in Infection and Immunity: Scope and Challenges in Vaccines Formulation. Front Cell Infect Microbiol 2018; 8:147. [PMID: 29868503 PMCID: PMC5954041 DOI: 10.3389/fcimb.2018.00147] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 04/20/2018] [Indexed: 01/01/2023] Open
Abstract
Deficiency of leptin (ob/ob) and/or desensitization of leptin signaling (db/db) and elevated expression of suppressor of cytokine signaling-3 (SOCS3) reported in obesity are also reported in a variety of pathologies including hypertriglyceridemia, insulin resistance, and malnutrition as the risk factors in host defense system. Viral infections cause the elevated SOCS3 expression, which inhibits leptin signaling. It results in immunosuppression by T-regulatory cells (Tregs). The host immunity becomes incompetent to manage pathogens' attack and invasion, which results in the accelerated infections and diminished vaccine-specific antibody response. Leptin was successfully used as mucosal vaccine adjuvant against Rhodococcus equi. Leptin induced the antibody response to Helicobacter pylori vaccination in mice. An integral leptin signaling in mucosal gut epithelial cells offered resistance against Clostridium difficile and Entameoba histolytica infections. We present in this review, the intervention of leptin in lethal diseases caused by microbial infections and propose the possible scope and challenges of leptin as an adjuvant tool in the development of effective vaccines.
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Affiliation(s)
- Dayakar Alti
- School of Life Sciences, University of Hyderabad, Hyderabad, India
| | | | - Suresh K Kalangi
- School of Life Sciences, University of Hyderabad, Hyderabad, India
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21
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Miura K, Ishioka M, Iijima K. The Roles of the Gut Microbiota and Toll-like Receptors in Obesity and Nonalcoholic Fatty Liver Disease. J Obes Metab Syndr 2017; 26:86-96. [PMID: 31089501 PMCID: PMC6484897 DOI: 10.7570/jomes.2017.26.2.86] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2017] [Revised: 02/28/2017] [Accepted: 03/16/2017] [Indexed: 02/06/2023] Open
Abstract
Obesity is characterized by low-grade chronic inflammation and is closely associated with the cardiovascular diseases, diabetes, and nonalcoholic fatty liver disease. Emerging data demonstrate that the gut microbiota contributes to the development of obesity by regulating the innate immune system, including the Toll-like receptors (TLRs): an altered gut microbiota composition and elevated TLR ligands are observed in obese mice and humans. The changes in the gut microbiota include an increased abundance of Firmicutes phylum and a decreased abundance of Bacteroidetes phylum. The population of beneficial bacteria that function as probiotics is decreased whereas harmful bacteria that can produce lipopolysaccharide, a TLR4 ligand, are increased in the obese state. In addition, the gut permeability is increased in obesity, which allows the delivery of larger amounts of bacterial components to the liver through the portal vein. Immune cells recognize these bacterial components through TLRs and produce diverse cytokines that kill invading pathogens. However, the sustained activation of TLR signaling induces host damage due to chronic exposure to harmful cytokines, which are produced from TLR expressing cells, including monocytes/macrophages. In the obese state, the expression of TLR is increased in several organs, including the adipose tissue and the liver. At the cell level, negative regulators of TLR signaling are suppressed, leading to activation of TLR signaling. These alterations promote inflammation in many organs. Thus, the gut microbiota and TLR signaling are therapeutic targets in patients with obesity and its related diseases.
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Affiliation(s)
- Kouichi Miura
- Department of Gastroenterology, Akita University Graduate School of Medicine, Akita, Japan
| | - Mitsuaki Ishioka
- Department of Gastroenterology, Akita University Graduate School of Medicine, Akita, Japan
| | - Katsunori Iijima
- Department of Gastroenterology, Akita University Graduate School of Medicine, Akita, Japan
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22
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Abstract
Obesity provokes an imbalance in the immune system, including an aberrant type I interferon response during some viral infections and after TLR stimulation. SOCS3 overexpression and altered systemic leptin levels could be responsible for the reduced type I interferon production in people with obesity and, eventually, significantly increase the risk of viral infection. The aim of this study was to determine whether SOCS3- and leptin-induced tolerance are responsible for the reduced type I interferon production in people with obesity. SOCS3 overexpression in PBMCs from people with obesity was inhibited with the small interfering RNA (siRNA) assay, and leptin-induced tolerance was evaluated in PBMCs from non-obese volunte\ers and U937 cells treated with TLR ligands. SOCS3, but not SOCS1, gene silencing via siRNA increased the type I interferon response in PBMCs obtained from people with obesity. On the other hand, leptin induced SOCS3 expression and inhibited type I interferons in PBMCs from healthy donors and in U937 monocytes stimulated with TLR ligands. Taken together, these results demonstrate that reduced type I interferon production in obesity is caused by SOCS3 overexpression as well as tolerance induced by leptin. Here, we demonstrate a key role of leptin and SOCS3 in inhibiting the type I interferon response during obesity.
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23
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Fabersani E, Abeijon-Mukdsi MC, Ross R, Medina R, González S, Gauffin-Cano P. Specific Strains of Lactic Acid Bacteria Differentially Modulate the Profile of Adipokines In Vitro. Front Immunol 2017; 8:266. [PMID: 28348560 PMCID: PMC5346559 DOI: 10.3389/fimmu.2017.00266] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 02/23/2017] [Indexed: 12/12/2022] Open
Abstract
Obesity induces local/systemic inflammation accompanied by increases in macrophage infiltration into adipose tissue and production of inflammatory cytokines, chemokines, and hormones. Previous studies have shown that probiotics could improve the intestinal dysbiosis induced by metabolic diseases such as obesity, diabetes, and metabolic syndrome. Microorganisms could (directly or indirectly) affect adipokine levels due to their capacity to induce translocation of several intestinal microbial antigens into systemic circulation, which could lead to metabolic endotoxemia or produce immunomodulation in different organs. The aim of the present study was to select non-inflammatory lactic acid bacteria (LAB) strains with the capacity to modulate adipokine secretion by the adipose tissue. We wish to elucidate the role of potential probiotic strains in the regulation of the cross talking between immune cells such as macrophages and adipose cells. Mouse macrophage cell line RAW 264.7 was used for evaluating the ability of 14 LAB strains to induce cytokine production. The LAB strains were chosen based on their previously studied beneficial properties in health. Then, in murine adipocyte culture and macrophage–adipocyte coculture, we determined the ability of these strains to induce cytokines and leptin secretion. Tumor necrosis factor alpha, interleukin 6 (IL-6), IL-10, monocyte chemoattractant protein-1, and leptin levels were measured in cell supernatants. We also performed the detection and quantification of leptin receptor (Ob-Rb) expression in macrophage cell lines stimulated by these LAB strains. Differential secretion profile of cytokines in macrophage cells induced by LAB strains was observed. Also, the levels of Ob-Rb expression diverged among different LAB strains. In LAB-stimulated coculture cells (adipocytes and macrophages), we observed differential production of leptin and cytokines. Furthermore, we detected lower production levels in single culture than cocultured cells. The principal component analysis showed an association between the four clusters of strains established according to their inflammatory profiles and leptin adipocyte production and leptin receptor expression in macrophages. We conclude that coculture is the most appropriate system for selecting strains with the ability to modulate adipokine secretion. The use of microorganisms with low and medium inflammatory properties and ability to modulate leptin levels could be a strategy for the treatment of some metabolic diseases associated with dysregulation of immune response.
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Affiliation(s)
- Emanuel Fabersani
- Centro de Referencia para Lactobacilos (CERELA) - CONICET , Tucumán , Argentina
| | - María Claudia Abeijon-Mukdsi
- Centro de Referencia para Lactobacilos (CERELA) - CONICET, Tucumán, Argentina; Facultad Ciencias de la Salud, Universidad del Norte Santo Tomás de Aquino (UNSTA), Tucumán, Argentina
| | - Romina Ross
- Facultad Ciencias de la Salud, Universidad del Norte Santo Tomás de Aquino (UNSTA), Tucumán, Argentina; Universidad Nacional de Tucumán (UNT), Tucumán, Argentina
| | - Roxana Medina
- Centro de Referencia para Lactobacilos (CERELA) - CONICET, Tucumán, Argentina; Universidad Nacional de Tucumán (UNT), Tucumán, Argentina
| | | | - Paola Gauffin-Cano
- Centro de Referencia para Lactobacilos (CERELA) - CONICET, Tucumán, Argentina; Facultad Ciencias de la Salud, Universidad del Norte Santo Tomás de Aquino (UNSTA), Tucumán, Argentina
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Abella V, Scotece M, Conde J, Pino J, Gonzalez-Gay MA, Gómez-Reino JJ, Mera A, Lago F, Gómez R, Gualillo O. Leptin in the interplay of inflammation, metabolism and immune system disorders. Nat Rev Rheumatol 2017; 13:100-109. [PMID: 28053336 DOI: 10.1038/nrrheum.2016.209] [Citation(s) in RCA: 323] [Impact Index Per Article: 46.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Leptin is one of the most relevant factors secreted by adipose tissue and the forerunner of a class of molecules collectively called adipokines. Initially discovered in 1994, its crucial role as a central regulator in energy homeostasis has been largely described during the past 20 years. Once secreted into the circulation, leptin reaches the central and peripheral nervous systems and acts by binding and activating the long form of leptin receptor (LEPR), regulating appetite and food intake, bone mass, basal metabolism, reproductive function and insulin secretion, among other processes. Research on the regulation of different adipose tissues has provided important insights into the intricate network that links nutrition, metabolism and immune homeostasis. The neuroendocrine and immune systems communicate bi-directionally through common ligands and receptors during stress responses and inflammation, and control cellular immune responses in several pathological situations including immune-inflammatory rheumatic diseases. This Review discusses the latest findings regarding the role of leptin in the immune system and metabolism, with particular emphasis on its effect on autoimmune and/or inflammatory rheumatic diseases, such as rheumatoid arthritis and osteoarthritis.
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Affiliation(s)
- Vanessa Abella
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
| | - Morena Scotece
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
| | - Javier Conde
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
| | - Jesús Pino
- SERGAS (Servizo Galego de Saude), Santiago University Clinical Hospital, Division of Orthopaedic Surgery and Traumatology, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
| | - Miguel Angel Gonzalez-Gay
- Epidemiology, Genetics and Atherosclerosis Research Group on Systemic Inflammatory Diseases, Universidad de Cantabria and IDIVAL, Hospital Universitario Marqués de Valdecilla, Av. Valdecilla, Santander 39008, Spain
| | - Juan J Gómez-Reino
- SERGAS (Servizo Galego de Saude), Santiago University Clinical Hospital, Division of Rheumatology, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
| | - Antonio Mera
- SERGAS (Servizo Galego de Saude), Santiago University Clinical Hospital, Division of Rheumatology, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
| | - Francisca Lago
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), Department of Cellular and Molecular Cardiology, CIBERCV (Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares), Building C, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
| | - Rodolfo Gómez
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
| | - Oreste Gualillo
- SERGAS (Servizo Galego de Saude) and IDIS (Instituto de Investigación Sanitaria de Santiago), The NEIRID Group (Neuroendocrine Interactions in Rheumatology and Inflammatory Diseases), Santiago University Clinical Hospital, Building C, Travesía da Choupana S/N, Santiago de Compostela 15706, Spain
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25
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Dattaroy D, Seth RK, Das S, Alhasson F, Chandrashekaran V, Michelotti G, Fan D, Nagarkatti M, Nagarkatti P, Diehl AM, Chatterjee S. Sparstolonin B attenuates early liver inflammation in experimental NASH by modulating TLR4 trafficking in lipid rafts via NADPH oxidase activation. Am J Physiol Gastrointest Liver Physiol 2016; 310:G510-25. [PMID: 26718771 PMCID: PMC4824178 DOI: 10.1152/ajpgi.00259.2015] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 12/28/2015] [Indexed: 01/31/2023]
Abstract
Although significant research data exist on the pathophysiology of nonalcoholic steatohepatitis (NASH), finding an efficient treatment regimen for it remains elusive. The present study used sparstolonin B (SsnB), a novel TLR4 antagonist derived from the Chinese herb Sparganium stoloniferum, as a possible drug to mitigate early inflammation in NASH. This study used an early steatohepatitic injury model in high-fat-fed mice with CYP2E1-mediated oxidative stress as a second hit. SsnB was administered for 1 wk along with bromodichloromethane (BDCM), an inducer of CYP2E1-mediated oxidative stress. Results showed that SsnB administration attenuated inflammatory morphology and decreased elevation of the liver enzyme alanine aminotransferase (ALT). Mice administered SsnB also showed decreased mRNA expression of proinflammatory cytokines TNF-α, IFN-γ, IL-1β, and IL-23, while protein levels of both TNF-α and IL-1β were significantly decreased. SsnB significantly decreased Kupffer cell activation as evidenced by reduction in CD68 and monocyte chemoattractant protein-1 (MCP1) mRNA and protein levels with concomitant inhibition of macrophage infiltration in the injured liver. Mechanistically, SsnB decreased TLR4 trafficking to the lipid rafts, a phenomenon described by the colocalization of TLR4 and lipid raft marker flotillin in tissues and immortalized Kupffer cells. Since we have shown previously that NADPH oxidase drives TLR4 trafficking in NASH, we studied the role of SsnB in modulating this pathway. SsnB prevented NADPH oxidase activation in vivo and in vitro as indicated by decreased peroxynitrite formation. In summary, the present study reports a novel use of the TLR4 antagonist SsnB in mitigating inflammation in NASH and in parallel shows a unique molecular mechanism of decreasing nitrative stress.
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Affiliation(s)
- Diptadip Dattaroy
- 1Environmental Health and Disease Laboratory, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina;
| | - Ratanesh Kumar Seth
- 1Environmental Health and Disease Laboratory, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina;
| | - Suvarthi Das
- 1Environmental Health and Disease Laboratory, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina;
| | - Firas Alhasson
- 1Environmental Health and Disease Laboratory, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina;
| | - Varun Chandrashekaran
- 1Environmental Health and Disease Laboratory, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina;
| | | | - Daping Fan
- 3Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, South Carolina; and
| | - Mitzi Nagarkatti
- 4Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, South Carolina
| | - Prakash Nagarkatti
- 4Department of Pathology, Microbiology and Immunology, University of South Carolina School of Medicine, Columbia, South Carolina
| | - Anna Mae Diehl
- 2Division of Gastroenterology, Duke University, Durham, North Carolina;
| | - Saurabh Chatterjee
- Environmental Health and Disease Laboratory, Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, South Carolina;
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26
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Naylor C, Petri WA. Leptin Regulation of Immune Responses. Trends Mol Med 2016; 22:88-98. [PMID: 26776093 DOI: 10.1016/j.molmed.2015.12.001] [Citation(s) in RCA: 162] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 12/06/2015] [Accepted: 12/10/2015] [Indexed: 12/19/2022]
Abstract
Leptin is a regulatory hormone with multiple roles in the immune system. We favor the concept that leptin signaling 'licenses' various immune cells to engage in immune responses and/or to differentiate. Leptin is an inflammatory molecule that is capable of activating both adaptive and innate immunity. It can also 'enhance' immune functions, including inflammatory cytokine production in macrophages, granulocyte chemotaxis, and increased Th17 proliferation. Leptin can also 'inhibit' cells; CD4(+) T cells are inhibited from differentiating into regulatory T cells in the presence of elevated leptin, while NK cells can exhibit impaired cytotoxicity under the same circumstances. Consequently, understanding the effect of leptin signaling is important to appreciate various aspects of immune dysregulation observed in malnutrition, obesity, and autoimmunity.
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Affiliation(s)
- Caitlin Naylor
- Medical Research Council Unit, Atlantic Blvd, Serrekunda, Gambia.
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27
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Interleukin-18 increases TLR4 and mannose receptor expression and modulates cytokine production in human monocytes. Mediators Inflamm 2015; 2015:236839. [PMID: 25873755 PMCID: PMC4383410 DOI: 10.1155/2015/236839] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 09/02/2014] [Accepted: 09/03/2014] [Indexed: 12/13/2022] Open
Abstract
Interleukin-18 is a proinflammatory cytokine belonging to the interleukin-1 family of cytokines. This cytokine exerts many unique biological and immunological effects. To explore the role of IL-18 in inflammatory innate immune responses, we investigated its impact on expression of two toll-like receptors (TLR2 and TLR4) and mannose receptor (MR) by human peripheral blood monocytes and its effect on TNF-α, IL-12, IL-15, and IL-10 production. Monocytes from healthy donors were stimulated or not with IL-18 for 18 h, and then the TLR2, TLR4, and MR expression and intracellular TNF-α, IL-12, and IL-10 production were assessed by flow cytometry and the levels of TNF-α, IL-12, IL-15, and IL-10 in culture supernatants were measured by ELISA. IL-18 treatment was able to increase TLR4 and MR expression by monocytes. The production of TNF-α and IL-10 was also increased by cytokine treatment. However, IL-18 was unable to induce neither IL-12 nor IL-15 production by these cells. Taken together, these results show an important role of IL-18 on the early phase of inflammatory response by promoting the expression of some pattern recognition receptors (PRRs) that are important during the microbe recognition phase and by inducing some important cytokines such as TNF-α and IL-10.
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28
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Toll-like receptor 2 mediates vascular contraction and activates RhoA signaling in vascular smooth muscle cells from STZ-induced type 1 diabetic rats. Pflugers Arch 2015; 467:2361-74. [PMID: 25600901 DOI: 10.1007/s00424-015-1688-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 01/06/2015] [Accepted: 01/07/2015] [Indexed: 01/11/2023]
Abstract
Increased vascular smooth muscle cell (VSMC) contraction is an early and critical contributor to the pathogenesis of vascular dysfunction in diabetes; however, knowledge regarding the underlying mechanisms is scarce. Toll-like receptor 2 (TLR2), a well-known component of the innate immunity, is expressed in VSMC and recently has been identified to be systemically activated in diabetes. Whether TLR2 is locally activated in the diabetic blood vessels and have effect on contraction is not known. In the current study, we examined the role of TLR2 in increased vascular contraction in diabetes. Utilizing rat model of type 1 diabetes (induced by streptozotocin (STZ)), we demonstrated that aortas from STZ-diabetic rats exhibit increased expression of TLR2 and its adaptor protein, myeloid differentiation primary response 88 (MyD88), as well as enhanced protein-protein interaction between TLR2 and MyD88, suggesting a TLR2 signaling activation. Blockade of TLR2 in intact aortas using anti-TLR2 antibody attenuated increased vascular contraction in STZ-diabetic rat as assessed by wire myograph. Activation of TLR2 by specific ligand in primary aortic VSMC cultures triggered activation of RhoA which was exacerbated in cells from STZ-diabetic rats than control rats. Activation of RhoA was accompanied by phosphorylation and therefore activation of its downstream targets myosin phosphatase target subunit I and myosin light chain (markers of VSMC contraction). Taken together, these results provide evidence for the role of TLR2 in increased contraction in diabetic blood vessels that involves RhoA signaling. Thus, targeting vascular TLR2 offers a promising drug target to treat vascular dysfunction in diabetes.
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29
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Jaworek J, Konturek SJ. Hormonal protection in acute pancreatitis by ghrelin, leptin and melatonin. World J Gastroenterol 2014; 20:16902-16912. [PMID: 25493003 PMCID: PMC4258559 DOI: 10.3748/wjg.v20.i45.16902] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 04/15/2014] [Accepted: 08/28/2014] [Indexed: 02/06/2023] Open
Abstract
Acute pancreatitis is a nonbacterial disease of the pancreas. The severe form of this ailment is characterized by high mortality. Whether acute pancreatitis develops as the severe type or resolves depends on the intensity of the inflammatory process which is counteracted by the recruitment of innate defense mechanisms. It has been shown that the hormones ghrelin, leptin and melatonin are able to modulate the immune function of the organism and to protect the pancreas against inflammatory damage. Experimental studies have demonstrated that the application of these substances prior to the induction of acute pancreatitis significantly attenuated the intensity of the inflammation and reduced pancreatic tissue damage. The pancreatic protective mechanisms of the above hormones have been related to the mobilization of non-specific immune defense, to the inhibition of nuclear factor kappa B and modulation of cytokine production, to the stimulation of heat shock proteins and changes of apoptotic processes in the acinar cells, as well as to the activation of antioxidant system of the pancreatic tissue. The protective effect of ghrelin seems to be indirect and perhaps dependent on the release of growth hormone and insulin-like growth factor 1. Leptin and ghrelin, but not melatonin, employ sensory nerves in their beneficial action on acute pancreatitis. It is very likely that ghrelin, leptin and melatonin could be implicated in the natural protection of the pancreatic gland against inflammatory damage because the blood levels of these substances increase in the initial phase of pancreatic inflammation. The above hormones could be a part of the innate resistance system which might remove noxious factors and could suppress or attenuate the inflammatory process in the pancreas.
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30
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Cannon JG, Sharma G, Sloan G, Dimitropoulou C, Baker RR, Mazzoli A, Kraj B, Mulloy A, Cortez-Cooper M. Leptin regulates CD16 expression on human monocytes in a sex-specific manner. Physiol Rep 2014; 2:2/10/e12177. [PMID: 25303952 PMCID: PMC4254102 DOI: 10.14814/phy2.12177] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Fat mass is linked mechanistically to the cardiovascular system through leptin, a 16 kDa protein produced primarily by adipocytes. In addition to increasing blood pressure via hypothalamic‐sympathetic pathways, leptin stimulates monocyte migration, cytokine secretion, and other functions that contribute to atherosclerotic plaque development. These functions are also characteristics of CD16‐positive monocytes that have been implicated in the clinical progression of atherosclerosis. This investigation sought to determine if leptin promoted the development of such CD16‐positive monocytes. Cells from 45 healthy men and women with age ranging from 20 to 59 years were analyzed. Circulating numbers of CD14++16++ monocytes, which are primary producers of TNFα, were positively related to plasma leptin concentrations (P < 0.0001), with a stronger correlation in men (P < 0.05 for leptin × sex interaction). In vitro, recombinant human leptin induced CD16 expression in a dose‐related manner (P = 0.02), with a stronger influence on monocytes from men (P = 0.03 for leptin × sex interaction). There were no sex‐related differences in total leptin receptor expression on any monocyte subtypes, relative expression of long versus short isoforms of the receptor, or soluble leptin receptor concentrations in the plasma. The number of circulating CD14+16++ monocytes, which preferentially migrate into nascent plaques, was positively related to systolic blood pressure (R = 0.56, P = 0.0008) and intima‐media thickness (R = 0.37, P = 0.03), and negatively related to carotid compliance (R = −0.39, P = 0.02). These observations indicate that leptin promotes the development of CD16‐positive monocyte populations in a sex‐specific manner and that these subpopulations are associated with diminished vascular function. e12177 Recombinant leptin induced CD16 expression on human monocytes in vitro in a dose‐ and sex‐specific manner. In vivo, CD16 expression on human monocytes correlated with plasma leptin concentrations in a sex‐specific manner. Blood pressure, carotid intima‐media thickness and carotid compliance were related to the number of circulating CD16‐positive monocytes.
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Affiliation(s)
- Joseph G Cannon
- College of Allied Health Sciences, Georgia Regents University, Augusta, Georgia
| | - Gyanendra Sharma
- Medical College of Georgia, Georgia Regents University, Augusta, Georgia
| | - Gloria Sloan
- College of Allied Health Sciences, Georgia Regents University, Augusta, Georgia
| | | | - R Randall Baker
- College of Allied Health Sciences, Georgia Regents University, Augusta, Georgia
| | - Andrew Mazzoli
- College of Allied Health Sciences, Georgia Regents University, Augusta, Georgia
| | - Barbara Kraj
- College of Allied Health Sciences, Georgia Regents University, Augusta, Georgia
| | - Anthony Mulloy
- Medical College of Georgia, Georgia Regents University, Augusta, Georgia
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31
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Conde J, Scotece M, Abella V, López V, Pino J, Gómez-Reino JJ, Gualillo O. An update on leptin as immunomodulator. Expert Rev Clin Immunol 2014; 10:1165-70. [DOI: 10.1586/1744666x.2014.942289] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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32
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Radom-Aizik S, Zaldivar FP, Haddad F, Cooper DM. Impact of brief exercise on circulating monocyte gene and microRNA expression: implications for atherosclerotic vascular disease. Brain Behav Immun 2014; 39:121-9. [PMID: 24423463 PMCID: PMC4101903 DOI: 10.1016/j.bbi.2014.01.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Revised: 12/24/2013] [Accepted: 01/04/2014] [Indexed: 12/14/2022] Open
Abstract
Physical activity can prevent and/or attenuate atherosclerosis, a disease clearly linked to inflammation. Paradoxically, even brief exercise induces a stress response and increases inflammatory cells like monocytes in the circulation. We hypothesized that exercise would regulate the expression of genes, gene pathways, and microRNAs in monocytes in a way that could limit pro-inflammatory function and drive monocytes to prevent, rather than contribute to, atherosclerosis. Twelve healthy men (22-30year old) performed ten 2-min bouts of cycle ergometer exercise at a constant work equivalent to an average of 82% of maximum O2 consumption interspersed with 1-min rest. Blood was drawn before and immediately after the exercise. Monocytes were isolated from peripheral blood mononuclear cells. Flow cytometry was used to identify monocyte subtypes. We used Affymetrix U133 + 2.0 arrays for gene expression and Agilent Human miRNA V2 Microarray for miRNAs. A stringent statistical approach (FDR <0.05) was used to determine that exercise significantly altered the expression of 894 annotated genes and 19 miRNAs. We found distinct gene alterations that were likely to direct monocytes in an anti-inflammatory, anti-atherogenic pathway, including the downregulation of monocyte TNF, TLR4, and CD36 genes and the upregulation of EREG and CXCR4. Exercise significantly altered a number of microRNAs that likely influence monocytes involvement in vascular health. Exercise leads to a novel genomic profile of circulating monocytes, which appears to promote cardiovascular health despite the overall stress response.
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Affiliation(s)
- Shlomit Radom-Aizik
- Pediatric Exercise and Genomics Research Center, Department of Pediatrics, UC Irvine School of Medicine, United States.
| | - Frank P. Zaldivar
- Pediatric Exercise and Genomics Research Center, Department of Pediatrics, UC Irvine School of Medicine
| | - Fadia Haddad
- Pediatric Exercise and Genomics Research Center, Department of Pediatrics, UC Irvine School of Medicine
| | - Dan M. Cooper
- Pediatric Exercise and Genomics Research Center, Department of Pediatrics, UC Irvine School of Medicine
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Kruis T, Batra A, Siegmund B. Bacterial translocation - impact on the adipocyte compartment. Front Immunol 2014; 4:510. [PMID: 24432024 PMCID: PMC3881001 DOI: 10.3389/fimmu.2013.00510] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 12/24/2013] [Indexed: 12/29/2022] Open
Abstract
Over the last decade it became broadly recognized that adipokines and thus the fat tissue compartment exert a regulatory function on the immune system. Our own group described the pro-inflammatory function of the adipokine leptin within intestinal inflammation in a variety of animal models. Following-up on this initial work, the aim was to reveal stimuli and mechanisms involved in the activation of the fat tissue compartment and the subsequent release of adipokines and other mediators paralleled by the infiltration of immune cells. This review will summarize the current literature on the possible role of the mesenteric fat tissue in intestinal inflammation with a focus on Crohn’s disease (CD). CD is of particular interest in this context since the transmural intestinal inflammation has been associated with a characteristic hypertrophy of the mesenteric fat, a phenomenon called “creeping fat.” The review will address three consecutive questions: (i) What is inducing adipocyte activation, (ii) which factors are released after activation and what are the consequences for the local fat tissue compartment and infiltrating cells; (iii) do the answers generated before allow for an explanation of the role of the mesenteric fat tissue within intestinal inflammation? With this review we will provide a working model indicating a close interaction in between bacterial translocation, activation of the adipocytes, and subsequent direction of the infiltrating immune cells. In summary, the models system mesenteric fat indicates a unique way how adipocytes can directly interact with the immune system.
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Affiliation(s)
- Tassilo Kruis
- Department of Medicine I (Gastroenterology, Rheumatology, Infectious Diseases), Charité - Universitätsmedizin Berlin , Berlin , Germany
| | - Arvind Batra
- Department of Medicine I (Gastroenterology, Rheumatology, Infectious Diseases), Charité - Universitätsmedizin Berlin , Berlin , Germany
| | - Britta Siegmund
- Department of Medicine I (Gastroenterology, Rheumatology, Infectious Diseases), Charité - Universitätsmedizin Berlin , Berlin , Germany
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34
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Huang CJ, Acevedo EO, Mari DC, Randazzo C, Shibata Y. Glucocorticoid inhibition of leptin- and lipopolysaccharide-induced interleukin-6 production in obesity. Brain Behav Immun 2014; 35:163-8. [PMID: 24126150 DOI: 10.1016/j.bbi.2013.10.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 10/01/2013] [Accepted: 10/04/2013] [Indexed: 12/21/2022] Open
Abstract
Obesity is considered a chronic inflammatory condition that enhances the risk of numerous inflammatory diseases, including diabetes and cardiovascular disease. Glucocorticoids (GCs) and synthetic therapeutic GCs are anti-inflammatory agents, but the exact functions of GCs in obesity-related inflammation are unknown. Therefore, the objective of this study was to examine the inhibitory effect of an exogenous GC (dexamethasone, DEX) on leptin- and lipopolysaccharide (LPS)-induced IL-6 production by peripheral blood mononuclear cells (PBMCs) ex vivo in obese subjects compared to normal-weight subjects. Blood samples were drawn from 14 obese (BMI>30 kg/m(2)) and 14 normal-weight (BMI<25 kg/m(2)) subjects. Plasma cortisol, TNF-α and IL-6 levels, and insulin resistance (HOMA-IR) were quantified. Subjects' PBMCs (1×10(6) cells/mL) were isolated and cultured with leptin (18.75 and 250 ng/mL) or LPS (10ng/mL) in the presence of DEX (0, 10(-8), 10(-7), and 10(-6) M), a synthetic GC, for 24 h; IL-6 levels and GC sensitivity (IC50) were assessed in the cultured supernatants. No differences in the plasma cortisol levels were found between the two groups. We found that obese subjects showed greater leptin- and LPS-induced IL-6 production compared to normal-weight subjects. The suppressive effect of DEX on leptin- and LPS-induced IL-6 production (IC50) was not different between the two groups. However, the IC50 of DEX for LPS-induced was correlated with BMI, waist circumference, and hip circumference. These findings suggest that reduced GC sensitivity may be an important mechanism in the up-regulation of selected obese inflammation.
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Affiliation(s)
- Chun-Jung Huang
- Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, United States.
| | - Edmund O Acevedo
- Department of Health and Human Performance, Virginia Commonwealth University, Richmond, VA, United States
| | - David C Mari
- Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, United States
| | - Christopher Randazzo
- Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, United States
| | - Yoshimi Shibata
- Department of Biomedical Science, College of Medicine, Florida Atlantic University, Boca Raton, FL, United States
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Abstract
Toll-like receptors (TLRs) are pattern-recognition receptors that recognize microbial/vial-derived components that trigger innate immune response, which indicate these molecules play a role in host defense against infection. The infection often precedes numerous disorders including glomerular diseases (glomerulonephritis (GN)). It is reported that TLRs are also involved in the risk and progression of GN, and TLRs may be potential therapeutic targets for GN. To date, a number of studies have found that TLRs are involved in the pathogenesis of GN. There is a paucity of reviews in the literature discussing signaling pathways and gene expression for TLRs in GN. This review was performed to provide a relatively complete signaling pathway flowchart for TLRs to the investigators who were interested in the roles of TLRs in the pathogenesis of GN. In the past decades, some studies were also performed to explore the association of TLRs gene expression with the risk of GN. However, the role of TLRs in the pathogenesis of GN remains controversial. Here, the signal transduction pathways of TLRs and its role of gene expression in the pathogenesis of GN were reviewed.
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Affiliation(s)
- Song Mao
- Department of Nephrology, Nanjing Children's Hospital, Affiliated to Nanjing Medical University , Nanjing , China
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36
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Abstract
Periodontitis is a common, chronic, inflammatory disease in which the supporting apparatus of the teeth is gradually destroyed, resulting in tooth mobility and tooth loss. Susceptibility to periodontitis is increased approximately three-fold in people with diabetes. Hyperglycemia leads to exacerbated tissue destruction and the clinical signs of periodontitis. There is evidence to support a two-way relationship between periodontitis and diabetes; not only does diabetes increase the risk for periodontitis, but periodontitis is associated with compromised glycemic control. Cooperation between health care teams would benefit the treatment of patients with diabetes and periodontitis.
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Affiliation(s)
- Philip M Preshaw
- School of Dental Sciences, Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4BW, UK.
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37
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Jitprasertwong P, Jaedicke KM, Nile CJ, Preshaw PM, Taylor JJ. Leptin enhances the secretion of interleukin (IL)-18, but not IL-1β, from human monocytes via activation of caspase-1. Cytokine 2013; 65:222-30. [PMID: 24275551 DOI: 10.1016/j.cyto.2013.10.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 09/10/2013] [Accepted: 10/28/2013] [Indexed: 01/22/2023]
Abstract
Circulating levels of leptin are elevated in type-2 diabetes mellitus (T2DM) and leptin plays a role in immune responses. Elevated circulating IL-18 levels are associated with clinical complications of T2DM. IL-18 regulates cytokine secretion and the function of a number of immune cells including T-cells, neutrophils and macrophages and as such has a key role in immunity and inflammation. Pro-inflammatory monocytes exhibiting elevated cytokine secretion are closely associated with inflammation in T2DM, however, little is known about the role of leptin in modifying monocyte IL-18 secretion. We therefore aimed to investigate the effect of leptin on IL-18 secretion by monocytes. We report herein that leptin increases IL-18 secretion in THP-1 and primary human monocytes but has no effect on IL-18mRNA. Leptin and LPS signalling in monocytes occurs by overlapping but distinct pathways. Thus, in contrast to a strong stimulation by LPS, leptin has no effect on IL-1βmRNA levels or IL-1β secretion. In addition, LPS stimulates the secretion of IL-6 but leptin did not whereas both treatments up regulate IL-8 secretion from the same cells. Although leptin (and LPS) has a synergistic effect with exogenous ATP on IL-18 secretion in both THP-1 and primary monocytes, experiments involving ATP assays and pharmacological inhibition of ATP signalling failed to provide any evidence that endogenous ATP secreted by leptin-stimulated monocytes was responsible for enhancement of monocyte IL-18 secretion by leptin. Analysis of the action of caspase-1 revealed that leptin up regulates caspase-1 activity and the effect of leptin on IL-18 release is prevented by caspase-1 inhibitor (Ac-YVAD-cmk). These data suggest that leptin activates IL-18 processing rather than IL-18 transcription. In conclusion, leptin enhances IL-18 secretion via modulation of the caspase-1 inflammasome function and acts synergistically with ATP in this regard. This process may contribute to aberrant immune responses in T2DM and other conditions of hyperleptinemia.
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Affiliation(s)
- Paiboon Jitprasertwong
- Centre for Oral Health Research and Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4BW, UK.
| | - Katrin M Jaedicke
- Centre for Oral Health Research and Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4BW, UK.
| | - Christopher J Nile
- Centre for Oral Health Research and Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4BW, UK.
| | - Philip M Preshaw
- Centre for Oral Health Research and Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4BW, UK.
| | - John J Taylor
- Centre for Oral Health Research and Institute of Cellular Medicine, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4BW, UK.
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38
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Huang CJ, Beasley KN, Acevedo EO, Franco RL, Jones TL, Mari DC, Shibata Y. Chitin enhances obese inflammation ex vivo. Hum Immunol 2013; 75:41-6. [PMID: 24055693 DOI: 10.1016/j.humimm.2013.09.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 08/31/2013] [Accepted: 09/11/2013] [Indexed: 10/26/2022]
Abstract
Infection has been implicated as a co-risk factor for obesity, but the mechanism remains uncertain. Elevated levels of plasma chitinase 3-like 1 (CHI3L1) are found in obese individuals. Since CHI3L1 is produced by activated immune cells including macrophages and recognizes microbial N-acetylglucosamine polymer (chitin), we asked whether the plasma CHI3L1 protein change in obese individuals might alter their innate immune response to chitin. Thirty-six subjects (15 obese and 21 non-obese), ages 18-30 years, were recruited. Peripheral blood mononuclear cells (PBMCs) were cultured with chitin microparticles (CMP; 1-10 μm) for 24h; tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and CHI3L1 in the culture supernatants were measured. We chose CMP, since neither large chitin beads (40-100 μm), chitosan microparticles (1-10 μm), nor soluble chitin induced the cytokine/CHI3L1 production by PBMCs isolated from non-obese PBMCs ex vivo. We found that the quantity of IL-6, but not TNF-α or CHI3L1, induced by CMP was significantly correlated with plasma IL-6, BMI, waist/hip circumferences, fasting plasma insulin, and insulin resistance. These findings suggest that chitin, a substrate of CHI3L1, further promotes obese inflammation in a size- and chemical composition- dependent manner.
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Affiliation(s)
- Chun-Jung Huang
- Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, United States.
| | - Kathleen N Beasley
- School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Edmund O Acevedo
- Department of Health and Human Performance, Virginia Commonwealth University, Richmond, VA, United States
| | - Robert L Franco
- Department of Health and Human Performance, Virginia Commonwealth University, Richmond, VA, United States
| | - Tamekia L Jones
- Children's Foundation Research Institute, Departments of Pediatrics and Preventive Medicine, University of Tennessee Health Science Center, Memphis, TN, United States
| | - David C Mari
- Department of Exercise Science and Health Promotion, Florida Atlantic University, Boca Raton, FL, United States
| | - Yoshimi Shibata
- Department of Biomedical Science, College of Medicine, Florida Atlantic University, Boca Raton, FL, United States
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