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Gu J, Yan GM, Kong XL, Zhang YY, Huang LH, Lu HM. Assessing the causal relationship between immune traits and systemic lupus erythematosus by bi-directional Mendelian randomization analysis. Mol Genet Genomics 2023; 298:1493-1503. [PMID: 37845373 DOI: 10.1007/s00438-023-02071-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 09/23/2023] [Indexed: 10/18/2023]
Abstract
Previous studies have observed relationships between immune cells and systemic lupus erythematosus (SLE), but their causal links remain undetermined. Based on the public available genome-wide association studies (GWAS) summary statistics, we conducted two-sample Mendelian randomization (MR) to evaluate the associations between 731 immune phenotypes and SLE pairs. Pairwise pleiotropy analysis was performed to identify pleiotropic genes for significant immunophenotype-SLE pairs. A comprehensive gene function analysis was undertaken to explore the mechanisms of immune cells in SLE. By using the instrumental variables extracted from GWAS data, we observed that increased levels of five immune phenotypes were causally associated with SLE risk (FDR < 0.05), that were CD20 on IgD+ CD38- naïve, BAFF-R on IgD+ CD38dim, CD39+ secreting Treg AC, CD14- CD16+ monocyte AC, and HLA DR on CD14+ monocyte. Pairwise gene-based analyses identified a total of 38 pleiotropic genes for 5 significant pairs identified and gene set enrichment analysis revealed the involvement of the identified pleiotropic genes in complex pathways (i.e., systemic lupus erythematosus, an integral component of luminal side of endoplasmic reticulum membrane, C-type lectin receptor signaling pathway and regulation of hormone secretion). This study demonstrates that the immune response influences the progression of SLE in a complex pattern. These findings greatly improve our understanding of the interaction between immune response and SLE risk and also aid in the design of therapeutic strategies from an immunological perspective.
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Affiliation(s)
- Jie Gu
- Department of Outpatient and Emergency, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Guan-Min Yan
- Department of Outpatient and Emergency, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Xiao-Lin Kong
- Department of Outpatient and Emergency, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Yin-Ying Zhang
- Department of Outpatient and Emergency, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People's Republic of China
| | - Li-Hong Huang
- Department of Biostatistics, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China.
| | - Hui-Min Lu
- Department of Outpatient and Emergency, First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, People's Republic of China.
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Pan Q, Chen X, Liao S, Chen X, Zhao C, Xu YZ, Liu HF. Updated advances of linking psychosocial factors and sex hormones with systemic lupus erythematosus susceptibility and development. PeerJ 2019; 7:e7179. [PMID: 31275761 PMCID: PMC6598654 DOI: 10.7717/peerj.7179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 05/22/2019] [Indexed: 12/17/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that primarily affects women, especially those of reproductive age. Genetics, environment, and gene-environment interactions play key roles in the development of SLE. Despite the numerous susceptibility genes of SLE identified to date, gene therapy is far from a clinical reality. Thus, more attention should be paid to the risk factors and underlying mechanisms of SLE. Currently, it is reported that psychosocial factors and sex hormones play vital roles in patients with SLE, which still need further investigated. The purpose of this review is to update the roles and mechanisms of psychosocial factors and sex hormones in the susceptibility and development of SLE. Based on review articles and reports in reputable peer-reviewed journals and government websites, this paper summarized psychosocial factors (e.g., alexithymia, depression, anxiety, negative emotions, and perceived stress) and sex hormones (e.g., estrogens, progesterone, androgens, and prolactin) involved in SLE. We further explore the mechanisms linking these factors with SLE susceptibility and development, which can guide the establishment of practical measures to benefit SLE patients and offer new ideas for therapeutic strategies.
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Affiliation(s)
- Qingjun Pan
- Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Division of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Xiaoqun Chen
- Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Division of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Shuzhen Liao
- Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Division of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Xiaocui Chen
- Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Division of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Chunfei Zhao
- Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Division of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Yong-Zhi Xu
- Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Division of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
| | - Hua-Feng Liu
- Key Laboratory of Prevention and Management of Chronic Kidney Disease of Zhanjiang City, Institute of Nephrology, Division of Nephrology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, China
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Lai W, Cai Y, Zhou J, Chen S, Qin C, Yang C, Liu J, Xie X, Du C. Deficiency of the G protein Gαq ameliorates experimental autoimmune encephalomyelitis with impaired DC-derived IL-6 production and Th17 differentiation. Cell Mol Immunol 2017; 14:557-567. [PMID: 28216651 DOI: 10.1038/cmi.2016.65] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 11/03/2016] [Accepted: 11/03/2016] [Indexed: 12/26/2022] Open
Abstract
Many G protein-coupled receptors (GPCRs) are reported to be involved in the pathogenesis of multiple sclerosis (MS), and ~40% of all identified GPCRs rely on the Gαq/11 G protein family to stimulate inositol lipid signaling. However, the function of Gα subunits in MS pathogenesis is still unknown. In this study, we attempted to determine the role of Gαq in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), a well-known mouse model of MS. We discovered that compared with wild-type mice, Gαq-knockout mice exhibited less severe EAE symptoms, with lower clinical scores, reduced leukocyte infiltration and less extensive demyelination. Moreover, a significantly lower percentage of Th17 cells, one of the key players in MS pathogenesis, was observed in Gαq-knockout EAE mice. Studies in vitro demonstrated that deficiency of Gαq in CD4+ T cells directly impaired Th17 differentiation. In addition, deficiency of Gαq significantly impaired DC-derived IL-6 production, thus inhibiting Th17 differentiation and the Gαq-PLCβ-PKC and Gαq-MAPKs signaling pathways involved in the reduced IL-6 production by DCs. In summary, our data highlighted the critical role of Gαq in regulating Th17 differentiation and MS pathogenesis.
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Affiliation(s)
- Weiming Lai
- Department of Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Yingying Cai
- Department of Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Jinfeng Zhou
- Department of Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Shuai Chen
- Department of Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Chaoyan Qin
- Department of Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Cuixia Yang
- Department of Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
| | - Junling Liu
- Department of Biochemistry and Molecular Cell Biology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Xin Xie
- National Center for Drug Screening, CAS Key Laboratory of Receptor Research, Chinese Academy of Sciences, Shanghai Institute of Materia Medica, Shanghai 201203, China
| | - Changsheng Du
- Department of Central Laboratory, Shanghai Tenth People's Hospital of Tongji University, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China.,Shanghai Key Laboratory of Signaling and Disease Research, School of Life Sciences and Technology, Tongji University, Shanghai 200092, China
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Poulsen CB, Mortensen MB, Koechling W, Sørensen CB, Bentzon JF. Differences in Hypercholesterolemia and Atherogenesis Induced by Common Androgen Deprivation Therapies in Male Mice. J Am Heart Assoc 2016; 5:e002800. [PMID: 26908406 PMCID: PMC4802473 DOI: 10.1161/jaha.115.002800] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Accepted: 01/13/2016] [Indexed: 02/01/2023]
Abstract
BACKGROUND Treatment of prostate cancer often involves androgen deprivation therapy (ADT) by gonadotropin-releasing hormone (GnRH) receptor agonists, GnRH receptor antagonists, or orchiectomy. ADT may increase the rate of cardiovascular disease events, but recent clinical studies suggested that not all means of ADT carry the same risk, raising the possibility of non-testosterone-mediated effects of different forms of ADT on atherosclerosis. Here we compared effects of ADT on atherosclerosis in intact and orchiectomized Apoe-deficient mice. METHODS AND RESULTS Chow-fed Apoe-deficient mice were allocated to orchiectomy and/or monthly injections with the GnRH receptor agonist leuprolide or the GnRH receptor antagonist degarelix. Atherosclerosis was quantified at 26 weeks of age in the aortic arch by en face examination and in the aortic root by histology. In intact Apoe-deficient mice, all types of ADT reduced testosterone production to castration levels. Although hypercholesterolemia was accentuated in leuprolide-treated mice, the amount and composition of atherosclerosis was not different between the different types of ADT. In orchiectomized Apoe-deficient mice, leuprolide, but not degarelix, augmented hypercholesterolemia, changed body, thymus, and spleen weights, and increased atherosclerosis in the aortic root. No direct effects of the drugs were detectable on cytokine secretion from murine bone marrow-derived macrophages or on splenocyte proliferation. CONCLUSIONS No differences in the development of atherosclerosis were detected among groups of intact Apoe-deficient mice treated with different types of ADT. A pro-atherogenic, possibly cholesterol-mediated, effect of leuprolide was seen in orchiectomized mice that might be relevant for understanding the potential cardiovascular risk associated with GnRH agonist-based ADT.
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Affiliation(s)
- Christian Bo Poulsen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Martin Bødtker Mortensen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Wolfgang Koechling
- Non-Clinical Development, Ferring Pharmaceuticals A/S, Copenhagen, Denmark
| | - Charlotte Brandt Sørensen
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark
| | - Jacob Fog Bentzon
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark Centro Nacional de Investigaciones Cardiovasculares Carlos III, Madrid, Spain
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Abstract
Heterotrimeric G proteins can be divided into Gi, Gs, Gq/11, and G12/13 subfamilies according to their α subunits. The main function of G proteins is transducing signals from G protein coupled receptors (GPCRs), a family of seven transmembrane receptors. In recent years, studies have demonstrated that GPCRs interact with Gq, a member of the Gq/11 subfamily of G proteins. This interaction facilitates the vital role of this family of proteins in immune regulation and autoimmunity, particularly for Gαq, which is considered the functional α subunit of Gq protein. Therefore, understanding the mechanisms through which Gq-coupled receptors control autoreactive lymphocytes is critical and may provide insights into the treatment of autoimmune disorders. In this review, we summarize recent advances in studies of the role of Gq-coupled receptors in autoimmunity, with a focus on their pathologic role and downstream signaling.
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Allergic manifestations and cutaneous histamine responses in patients with McCune Albright syndrome. World Allergy Organ J 2013; 6:9. [PMID: 23663565 PMCID: PMC3817837 DOI: 10.1186/1939-4551-6-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 04/16/2013] [Indexed: 11/28/2022] Open
Abstract
Background McCune Albright syndrome (MAS) is a rare disorder characterized by precocious puberty, café-au-lait spots, and fibrous dysplasia. Its cause is an activating mutation in the GNAS gene, encoding a subunit of the stimulatory G protein, Gsalpha (Gsα). The action of any mediator that signals via Gsα and cyclic AMP can be up regulated in MAS. We had observed gastritis, gastroesophageal reflux, and anaphylaxis in McCune Albright patients. Objective As histamine is known to signal via histamine 1 (H1) and histamine 2 (H2) receptors, which couple with stimulatory G proteins, we attempted to mechanistically link histamine responsiveness to the activating GNAS mutation. We hypothesized that responsiveness to histamine skin testing would differ between MAS patients and healthy controls. Patients and methods After obtaining informed consent, we performed a systematic review of histamine responsiveness and allergic manifestations in 11 MAS patients and 11 sex-matched, Tanner-stage matched controls. We performed skin prick testing, quantifying the orthogonal diameters of wheals and erythema. We also quantitated G protein mRNA expression. Results The peak wheal and flare responses to histamine were significantly higher in MAS patients compared to controls. Conclusions This study suggests that MAS patients may be at risk for exaggerated histamine responsiveness compared to unaffected controls.
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Salazar KD, Miller MR, Barnett JB, Schafer R. Evidence for a Novel Endocrine Disruptor: The Pesticide Propanil Requires the Ovaries and Steroid Synthesis to Enhance Humoral Immunity. Toxicol Sci 2006; 93:62-74. [PMID: 16788000 DOI: 10.1093/toxsci/kfl038] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Steroid hormones are known to affect the humoral immune response to a variety of antigens. However, the mechanisms regulating these effects are poorly understood. The immunotoxic chemical propanil and estrogen have similar effects on the immune system including augmentation of humoral immune responses. Propanil enhances the number of phosphorylcholine (PC)-specific IgG2b, IgG3, and IgM antibody-secreting cells (ASCs) in the spleen four- to sixfold 7 days after vaccination of female C57BL/6 mice with heat-killed Streptococcus pneumoniae. Several experiments were performed to test the hypothesis that propanil increases the response via an estrogenic pathway. Ovariectomy abrogated the effect of propanil on the PC-specific ASC response. Both in vitro and in vivo assays indicate that propanil does not bind either estrogen receptor (ER) alpha or beta. Exogenous estradiol administration in ovariectomized mice failed to restore the effect of propanil on the PC response. Treatment of female mice with a pure ER antagonist, ICI 182,780, or the progesterone antagonist RU486 did not inhibit the increase in ASCs. These data suggest that estrogen and progesterone do not regulate the effect of propanil. However, complete inhibition of steroid synthesis with the gonadotropin-releasing hormone (GnRH) antagonist antide abrogated the increased response in propanil-treated mice, indicating a necessary role for steroid synthesis. Experiments in male mice demonstrated that propanil increased the number of ASCs comparable to female mice. However, orchiectomy did not inhibit this effect, suggesting that androgens do not regulate the amplification of the humoral response. These data suggest a novel role for the ovarian hormones in the regulation of the PC-specific antibody response.
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Affiliation(s)
- Keith D Salazar
- Department of Microbiology, Immunology and Cell Biology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, West Virginia 26506, USA
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Leposavić G, Pekić S, Kosec D. Gonadotropin-releasing hormone agonist administration affects the thymopoiesis in adult female rats independently on gonadal hormone production. Am J Reprod Immunol 2005; 53:30-41. [PMID: 15667523 DOI: 10.1111/j.1600-0897.2004.00244.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PROBLEM In addition to having an indirect effect on the T-cell development by controlling the production of ovarian steroids, an accumulating body of evidence suggest that GnRH analogue (GnRH-A) administration may exert a thymopoietic regulatory effect that is not mediated by ovarian hormones. METHOD OF STUDY In non-ovariectomized (non-OVX) and OVX adult female AO rats treated s.c. with GnRH-A or saline (controls), over 14 days, were estimated the thymic cellularity and thymocyte expression of CD4/CD8/TCRalphabeta by stereological analysis and three-color flow cytometry, respectively. RESULTS GnRH-A in both groups of rats diminished the thymic cellularity. In non-OVX rats GnRH-A increased the relative numbers of immature cells (CD4-8-TCRalphabeta(-), CD4-8-TCRalphabeta(low) and CD4+8-TCRalphabeta(low)), and reduced those of positively selected CD4+8+TCRalphabeta(high) and mature (CD4-8+TCRalphabeta(high), CD4(+8)-TCRalphabeta(high)) cells, suggesting decelerated expression of TCRalphabeta followed by less efficient positive selection and further maturation of the selected cells. Differently, in OVX rats GnRH-A decreased the percentage of immature (CD4-8-TCRalphabeta(-), CD4+8+ TCRalphabeta(-)) cells and increased those of all TCRalphabeta(high) subsets, suggesting an increased rate of early thymocyte differentiation, more efficient positive selection and further maturation of the selected cells. CONCLUSIONS The effect of GnRH-A administration is affected by the presence of ovarian steroids.
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Affiliation(s)
- Gordana Leposavić
- Department of Physiology, Faculty of Pharmacy, Belgrade, Serbia and Montenegro.
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Li J, May W, McMurray RW. Pituitary hormones and systemic lupus erythematosus. ACTA ACUST UNITED AC 2005; 52:3701-12. [PMID: 16320320 DOI: 10.1002/art.21436] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Jing Li
- University of Mississippi Medical Center, Jackson, MS 39216, USA
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Pendse S, Ginsburg E, Singh AK. Strategies for preservation of ovarian and testicular function after immunosuppression. Am J Kidney Dis 2004; 43:772-81. [PMID: 15112167 DOI: 10.1053/j.ajkd.2004.01.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Gonadal toxicity as a side effect of cyclophosphamide therapy is a common long-term problem in the treatment of a variety of glomerular diseases. In both men and women treated with cyclophosphamide, the consequences of infertility can have great physical and emotional consequences; thus, this issue often has a critical role in the decision to decline treatment with cyclophosphamide. There exists a critical need for strategies for preservation of fertility in both men and women who require treatment with cyclophosphamide. This review explores emerging therapeutic options in this arena, which include sperm and oocyte cryopreservation, medical treatments such as testosterone therapy for men and gonadotropin-releasing hormone agonist therapy for both men and women, and, finally, the relatively new strategy of germ-cell transplantation for both ovarian and testicular tissue, which still remains in the experimental stages.
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Affiliation(s)
- Shona Pendse
- Renal Division, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
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Jacobson JD, Ansari MA. Immunomodulatory actions of gonadal steroids may be mediated by gonadotropin-releasing hormone. Endocrinology 2004; 145:330-6. [PMID: 12959991 DOI: 10.1210/en.2003-0510] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Estrogens are considered to be immunostimulatory, whereas androgens are considered to be immunosuppressive. We hypothesized that the divergent actions of gonadal steroids on the immune system may be mediated indirectly, via their potent divergent feedback effects on the hypothalamic hormone GnRH, which is itself immunostimulatory. We used the GnRH-deficient HPG/Bm mouse in an effort to disentangle the effects of gonadal steroids from the effects of GnRH. We randomized GnRH-deficient mice and their GnRH-sufficient littermates to receive androgens, estrogens, or GnRH. We subsequently measured B and T cell proliferative responses to mitogen and serum IgG levels. We demonstrate that estrogens exert stimulatory effects on B cell proliferation and serum IgG levels in the presence of GnRH but not in the absence of GnRH. Testosterone exerts suppressive effects on B cell function in the presence of GnRH but not in its absence. Androgens and estrogens exerted divergent actions on T cell function irrespective of the presence and absence of GnRH, although responses were markedly attenuated in GnRH-deficient mice. Our data suggest that the immunostimulatory effects of estrogen and the immunosuppressive effects of androgens on B cell function may be mediated indirectly via GnRH.
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Affiliation(s)
- Jill D Jacobson
- Section of Endocrinology, Children's Mercy Hospital, University of Missouri-Kansas Cisty School of Medicine, Kansas City, Missouri 64108, USA.
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Abstract
The exact patho-aetiology of systemic lupus erythematosus (SLE) remains elusive. An extremely complicated and multifactorial interaction among various genetic and environmental factors is probably involved. Multiple genes contribute to disease susceptibility. The interaction of sex, hormonal milieu, and the hypothalamo-pituitary-adrenal axis modifies this susceptibility and the clinical expression of the disease. Defective immune regulatory mechanisms, such as the clearance of apoptotic cells and immune complexes, are important contributors to the development of SLE. The loss of immune tolerance, increased antigenic load, excess T cell help, defective B cell suppression, and the shifting of T helper 1 (Th1) to Th2 immune responses leads to B cell hyperactivity and the production of pathogenic autoantibodies. Finally, certain environmental factors are probably required to trigger the disease.
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Affiliation(s)
- C C Mok
- Department of Medicine and Geriatrics, Tuen Mun Hospital, Tsing Chung Koon Road, New Territories, Hong Kong.
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Dixit VD, Yang H, Udhayakumar V, Sridaran R. Gonadotropin-releasing hormone alters the T helper cytokine balance in the pregnant rat. Biol Reprod 2003; 68:2215-21. [PMID: 12606332 DOI: 10.1095/biolreprod.102.012211] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The interactions between immune-endocrine and reproductive systems are heightened during pregnancy as an adaptive mechanism, and are regulated by a complex array of hormones and cytokines that control the survival of a semiallogeneic conceptus. GnRH can exert direct effects on the immune system via its receptor (GnRH-R) on lymphoid cells. In the present study, we employed in vitro, ex vivo, and in vivo approaches to investigate the role of GnRH in the modulation of T helper cytokines in pregnant rats undergoing termination of pregnancy. Day 8 pregnant rats were infused with a GnRH agonist (GnRH-Ag) for 24 h using an osmotic minipump. Sham control rats were infused with the vehicle, saline. Lymphocytes were isolated from sham and treated rats and polyclonally stimulated with immobilized anti-CD3 antibody. The levels of the signature T helper 1 (Th-1) cytokines (interferon-gamma [IFN-gamma] and interleukin-2 [IL-2]) and Th-2 cytokines (IL-4 and IL-10) were measured in culture supernatants. Using immunoflourescence confocal microscopy, we demonstrated for the first time the spatial localization of GnRH-R protein on the surface of lymphocytes. We observed a marked increase in IFN-gamma and inhibition of IL-4 production from lymphocytes of pregnant rats treated in vitro with different doses of GnRH-Ag. Further, the responsiveness of lymphocytes to produce IFN-gamma was markedly increased in cells cultured ex vivo from GnRH-Ag infused rats, whereas the capacity of lymphocytes to produce IL-4 was significantly inhibited. In addition, GnRH-Ag infusion in pregnant rats induced a shift toward Th-1 cytokines in the serum. We did not observe any significant difference in IL-2 and IL-10 production in response to GnRH-Ag. Our results suggest an additional function for GnRH as a Th-1 inducer and Th-2 inhibitor. GnRH can thus skew the cytokine balance to predominantly Th-1 type in pregnancy, leading to the termination of pregnancy in rats.
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Affiliation(s)
- Vishwa Deep Dixit
- Department of Physiology, Morehouse School of Medicine, Atlanta, Georgia 30310-1495, USA
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14
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Abstract
The hypothalamic homone gonadotropin-releasing hormone (GnRH) displays gender-specific actions. Pituitary responsiveness to GnRH is generally increased by estrogens and decreased by androgens. GnRH is now known to be produced by the immune system and to exert potent immunologic actions. Our central hypothesis is that gender differences in responsiveness to GnRH in the immune system play a pivotal role in the gender differences in immunity and autoimmunity. Studies in lupus-prone mice demonstrate that GnRH exacerbates murine lupus in a gender-specific fashion. Subsequent studies from our laboratory suggest that the gender differences in immunologic responsiveness to GnRH may relate to differences in the expression of the signal transducers through which GnRH acts, namely, the G proteins, Gs, and Gq/11. We have further demonstrated gender differences in second messengers for GnRH, IP3, and cAMF in immune cells. We have also demonstrated that GnRH agonist increases the quantities and/or activity of G proteins in immune cells in a gender-specific fashion. We speculate that gender differences in GnRH production and action, and in G protein expression play a role in a variety of autoimmune diseases that affect females predominantly.
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Affiliation(s)
- J D Jacobson
- Section of Endocrinology, Children's Mercy Hospital, University of Missouri-Kansas City School of Medicine, Kansas City, Missouri 64108, USA
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