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1.
Arch Sex Behav ; 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216784

RESUMO

Self-reported sexual orientation of transgender individuals occasionally changes over transition. Using functional magnetic resonance imaging, we tested the hypothesis that neural and behavioral patterns of sexual arousal in transgender individuals would shift from the assigned to the experienced gender (e.g., trans women's responses becoming more dissimilar to those of cis men and more similar to those of cis women). To this aim, trans women (N = 12) and trans men (N = 20) as well as cisgender women (N = 24) and cisgender men (N = 14) rated visual stimuli showing male-female, female-female or male-male intercourse for sexual arousal before and after four months of gender-affirming hormone therapy. A Bayesian framework allowed us to incorporate previous behavioral findings. The hypothesized changes could indeed be observed in the behavioral responses with the strongest results for trans men and female-female scenes. Activation of the ventral striatum supported our hypothesis only for female-female scenes in trans women. The respective application or depletion of androgens in trans men and trans women might partly explain this observation. The prominent role of female-female stimuli might be based on the differential responses they elicit in cis women and men or, in theory, the controversial concept of autogynephilia. We show that correlates of sexual arousal in transgender individuals might change in the direction of the experienced gender. Future investigations should elucidate the mechanistic role of sex hormones and the cause of the differential neural and behavioral findings.The study was registered at ClinicalTrials.gov (NCT02715232), March 22, 2016.

2.
Int J Transgend Health ; 24(4): 499-509, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901063

RESUMO

Objective: We aimed to investigate the effect of gender-affirming hormone therapy (GAHT) on cardiovascular disease risk factors focusing on glucose tolerance. Patients and Methods: This primarily translational study enrolled 16 transgender persons assigned female at birth (AFAB), 22 assigned male at birth (AMAB), and 33 age- and BMI-matched cisgender controls at the Medical University of Vienna from 2013 to 2020. A 3-Tesla MRI scan to measure intramyocardial, pancreatic, hepatic fat content and subcutaneous-to-visceral adipose tissue ratio (SAT/VAT-ratio), an oral glucose tolerance test (oGTT), bloodwork including brain natriuretic peptide (pro-BNP), sex hormones and two glucose-metabolism related biomarkers (adiponectin, betatrophin) were performed. Results: Estrogen intake was associated with higher fasting insulin (p = 0.034) and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) (p = 0.037), however, lower HbA1c levels (p = 0.031) in AMAB than cisgender males. Adiponectin (p = 0.001) and betatrophin (p = 0.034) levels were higher in AMAB than cisgender males, but similar to cisgender females. Compared to cisgender females, AFAB displayed no differences in glucose metabolism or SAT/VAT-ratio. AFAB had lower pro-BNP levels (p = 0.014), higher liver enzymes (AST: p = 0.011; ALT: p = 0.012) and lower HDL levels (p = 0.017) than cisgender females, but comparable levels to cisgender males. AMAB showed an increased heart rate (p < 0.001) and pro-BNP (p = 0.002) levels, but a more favorable SAT/VAT-ratio (p = 0.013) and lower creatine kinase (CK) (p = 0.001) than cisgender males. There were no relevant differences in organ fat content between transgender persons and their respective cisgender controls. Conclusion: In AMAB, most investigated parameters adapted to levels seen in cisgender females except for parameters related to fasted insulin resistance. AMAB should be monitored with respect to the development of insulin resistance.

3.
J Psychiatry Neurosci ; 48(5): E369-E375, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37751919

RESUMO

BACKGROUND: Among its pleiotropic properties, gender-affirming hormone therapy (GHT) affects regional brain volumes. The hypothalamus, which regulates neuroendocrine function and associated emotional and cognitive processes, is an intuitive target for probing GHT effects. We sought to assess changes to hypothalamus and hypothalamic subunit volumes after GHT, thereby honouring the region's anatomical and functional heterogeneity. METHODS: Individuals with gender dysphoria and cisgender controls underwent 2 MRI measurements, with a median interval of 145 days (interquartile range [IQR] 128.25-169.75 d, mean 164.94 d) between the first and second MRI. Transgender women (TW) and transgender men (TM) underwent the first MRI before GHT and the second MRI after approximately 4.5 months of GHT, which comprised estrogen and anti-androgen therapy in TW or testosterone therapy in TM. Hypothalamic volumes were segmented using FreeSurfer, and effects of GHT were tested using repeated-measures analysis of covariance. RESULTS: The final sample included 106 participants: 38 TM, 15 TW, 32 cisgender women (CW) and 21 cisgender men (CM). Our analyses revealed group × time interaction effects for total, left and right hypothalamus volume, and for several subunits (left and right inferior tubular, left superior tubular, right anterior inferior, right anterior superior, all p corr < 0.01). In TW, volumes decreased between the first and second MRI in these regions (all p corr ≤ 0.01), and the change from the first to second MRI in TW differed significantly from that in CM and CW in several subunits (p corr < 0.05). LIMITATIONS: We did not address the influence of transition-related psychological and behavioural changes. CONCLUSION: Our results suggest a subunit-specific effect of GHT on hypothalamus volumes in TW. This finding is in accordance with previous reports of positive and negative effects of androgens and estrogens, respectively, on cerebral volumes.


Assuntos
Emoções , Disforia de Gênero , Masculino , Feminino , Humanos , Disforia de Gênero/diagnóstico por imagem , Disforia de Gênero/tratamento farmacológico , Hipotálamo/diagnóstico por imagem , Testosterona
4.
Psychoneuroendocrinology ; 155: 106336, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37499299

RESUMO

BACKGROUND: Sex-specific differences in brain connectivity were found in various neuroimaging studies, though little is known about sex steroid effects on insular functioning. Based on well-characterized sex differences in emotion regulation, interoception and higher-level cognition, gender-dysphoric individuals receiving gender-affirming hormone therapy represent an interesting cohort to investigate how sex hormones might influence insular connectivity and related brain functions. METHODS: To analyze the potential effect of sex steroids on insular connectivity at rest, 11 transgender women, 14 transgender men, 20 cisgender women, and 11 cisgender men were recruited. All participants underwent two magnetic resonance imaging sessions involving resting-state acquisitions separated by a median time period of 4.5 months and also completed the Bermond-Vorst alexithymia questionnaire at the initial and final examination. Between scans, transgender subjects received gender-affirming hormone therapy. RESULTS: A seed based functional connectivity analysis revealed a significant 2-way interaction effect of group-by-time between right insula, cingulum, left middle frontal gyrus and left angular gyrus. Post-hoc tests demonstrated an increase in connectivity for transgender women when compared to cisgender men. Furthermore, spectral dynamic causal modelling showed reduced effective connectivity from the posterior cingulum and left angular gyrus to the left middle frontal gyrus as well as from the right insula to the left middle frontal gyrus. Alexithymia changes were found after gender-affirming hormone therapy for transgender women in both fantasizing and identifying. CONCLUSION: These findings suggest a considerable influence of estrogen administration and androgen suppression on brain networks implicated in interoception, own-body perception and higher-level cognition.


Assuntos
Disforia de Gênero , Transexualidade , Humanos , Masculino , Feminino , Disforia de Gênero/tratamento farmacológico , Identidade de Gênero , Transexualidade/tratamento farmacológico , Encéfalo , Imageamento por Ressonância Magnética/métodos , Hormônios Esteroides Gonadais/farmacologia , Esteroides
5.
Sci Rep ; 13(1): 7129, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37130874

RESUMO

The intermediate bacterial microbiota is a heterogeneous group that varies in the severity of the dysbiosis, from minor deficiency to total absence of vaginal Lactobacillus spp. We treated women with this vaginal dysbiosis in the first trimester of pregnancy using a vaginally applied lactobacilli preparation to restore the normal microbiota in order to delay the preterm delivery rate. Pregnant women with intermediate microbiota of the vagina and a Nugent score of 4 were enrolled in two groups: intermediate vaginal microbiota and a Nugent score of 4 with lactobacilli (IMLN4) and intermediate vaginal microbiota and a Nugent score of 4 without lactobacilli (IM0N4), with and without vaginal lactobacilli at baseline, respectively. Half of the women in each group received the treatment. Among women without lactobacilli (the IM0N4 group), the Nugent sore decreased by 4 points only in the women who received treatment, and gestational age at delivery and neonatal birthweight were both significantly higher in the treated subgroup than in the untreated subgroup (p = 0.047 and p = 0.016, respectively). This small study found a trend toward a benefit of treatment with vaginal lactobacilli during pregnancy.


Assuntos
Lacticaseibacillus rhamnosus , Microbiota , Probióticos , Recém-Nascido , Gravidez , Feminino , Humanos , Resultado da Gravidez , Disbiose/terapia , Estudos Prospectivos , Vagina/microbiologia , Lactobacillus , Probióticos/uso terapêutico
6.
EClinicalMedicine ; 54: 101702, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36263396

RESUMO

Background: There is limited data on human papillomaviruses (HPV) prevalence in transpeople due to low acceptance rate of screening methods. HPV tests from self-collected urine are gender-neutral, have a high acceptance, and have a comparable accuracy in females to clinician-collected samples. The aim of this study was to evaluate both the HPV prevalence in the urine in a large cohort of 200 transpeople with common risk profiles and the acceptability of such screening method. Methods: The study was conducted at the outpatient clinic for transpeople at the Department of Obstetrics and Gynaecology, Medical University of Vienna, Austria. 200 transpeople have been enrolled between May and October 2021. Inclusion criteria were gender identity dysphoria, age over 18 years, and adequate language skills.Subjects were asked to answer a survey concerning gender identity, established risk factors for HPV infections as well as their preference regarding urine or provider-collected cytology-/HPV-based screening, and to provide a urine sample. Five patients not able to provide urine were excluded. HPV genotyping was performed using a validated multiplex real-time PCR assay, which simultaneously detects 28 HPV genotypes. This trial is registered at ClinicalTrials.gov, NCT04864951. Findings: Overall HPV positivity was 19·0% (37/195), 24·2% in female to male, 11·8% in male to female, 26·3% in genderqueer/non binary/other subjects, 27·9% in subjects currently having a cervix, and 26·0% in subjects born with cervix. Independent of gender reassignment surgery, being born with a cervix was associated with a higher risk of HPV infections (p = 0·008), yet 42·3% (44/104) have never attended cervical cancer screening. Overall, 79·0% (154/195) of transpeople would prefer urine HPV tests to provider-collected HPV screening. Interpretation: HPV testing in self-collected urine samples provides a unique opportunity for screening of this hard-to-reach population and should be evaluated in further studies. Funding: None.

7.
Sci Adv ; 8(40): eabn6552, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36206339

RESUMO

T cell activation and function depend on Ca2+ signals mediated by store-operated Ca2+ entry (SOCE) through Ca2+ release-activated Ca2+ (CRAC) channels formed by ORAI1 proteins. We here investigated how SOCE controls T cell function in pulmonary inflammation during a T helper 1 (TH1) cell-mediated response to influenza A virus (IAV) infection and TH2 cell-mediated allergic airway inflammation. T cell-specific deletion of Orai1 did not exacerbate pulmonary inflammation and viral burdens following IAV infection but protected mice from house dust mite-induced allergic airway inflammation. ORAI1 controlled the expression of genes including p53 and E2F transcription factors that regulate the cell cycle in TH2 cells in response to allergen stimulation and the expression of transcription factors and cytokines that regulate TH2 cell function. Systemic application of a CRAC channel blocker suppressed allergic airway inflammation without compromising immunity to IAV infection, suggesting that inhibition of SOCE is a potential treatment for allergic airway disease.


Assuntos
Canais de Cálcio , Vírus da Influenza A , Alérgenos , Animais , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Citocinas/metabolismo , Fatores de Transcrição E2F , Inflamação , Camundongos , Proteína ORAI1/genética , Proteína ORAI1/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/metabolismo
8.
EMBO Mol Med ; 14(9): e15687, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-35919953

RESUMO

Inflammatory bowel disease (IBD) is characterized by dysregulated intestinal immune responses. Using mass cytometry (CyTOF) to analyze the immune cell composition in the lamina propria (LP) of patients with ulcerative colitis (UC) and Crohn's disease (CD), we observed an enrichment of CD4+ effector T cells producing IL-17A and TNF, CD8+ T cells producing IFNγ, T regulatory (Treg) cells, and innate lymphoid cells (ILC). The function of these immune cells is regulated by store-operated Ca2+ entry (SOCE), which results from the opening of Ca2+ release-activated Ca2+ (CRAC) channels formed by ORAI and STIM proteins. We observed that the pharmacologic inhibition of SOCE attenuated the production of proinflammatory cytokines including IL-2, IL-4, IL-6, IL-17A, TNF, and IFNγ by human colonic T cells and ILCs, reduced the production of IL-6 by B cells and the production of IFNγ by myeloid cells, but had no effect on the viability, differentiation, and function of intestinal epithelial cells. T cell-specific deletion of CRAC channel genes in mice showed that Orai1, Stim1, and Stim2-deficient T cells have quantitatively distinct defects in SOCE, which correlate with gradually more pronounced impairment of cytokine production by Th1 and Th17 cells and the severity of IBD. Moreover, the pharmacologic inhibition of SOCE with a selective CRAC channel inhibitor attenuated IBD severity and colitogenic T cell function in mice. Our data indicate that SOCE inhibition may be a suitable new approach for the treatment of IBD.


Assuntos
Canais de Cálcio Ativados pela Liberação de Cálcio , Doenças Inflamatórias Intestinais , Animais , Linfócitos T CD8-Positivos/metabolismo , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Humanos , Imunidade Inata , Interleucina-17/metabolismo , Interleucina-6/metabolismo , Camundongos , Proteína ORAI1/metabolismo , Molécula 1 de Interação Estromal/genética , Células Th17/metabolismo
9.
Psychoneuroendocrinology ; 133: 105381, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34416504

RESUMO

The sex hormones testosterone and estradiol influence brain structure and function and are implicated in the pathogenesis, prevalence and disease course of major depression. Recent research employing gender-affirming hormone treatment (GHT) of gender dysphoric individuals and utilizing positron emission tomography (PET) indicates increased serotonin transporter binding upon high-dosages of testosterone treatment. Here, we investigated the effects of GHT on levels of monoamine oxidase A (MAO-A), another key target of antidepressant treatment. Participants underwent PET with the radioligand [11C]harmine to assess cerebral MAO-A distribution volumes (VT) before and four months after initiation of GHT. By the time this study was terminated for technical reasons, 18 transgender individuals undergoing GHT (11 transmen, TM and 7 transwomen, TW) and 17 cis-gender subjects had been assessed. Preliminary analysis of available data revealed statistically significant MAO-A VT reductions in TM under testosterone treatment in six of twelve a priori defined regions of interest (middle frontal cortex (-10%), anterior cingulate cortex (-9%), medial cingulate cortex (-10.5%), insula (-8%), amygdala (-9%) and hippocampus (-8.5%, all p<0.05)). MAO-A VT did not change in TW receiving estrogen treatment. Despite the limited sample size, pronounced MAO-A VT reduction could be observed, pointing towards a potential effect of testosterone. Considering MAO-A's central role in regulation of serotonergic neurotransmission, changes to MAO-A VT should be further investigated as a possible mechanism by which testosterone mediates risk for, symptomatology of, and treatment response in affective disorders.


Assuntos
Encéfalo , Monoaminoxidase , Testosterona , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Monoaminoxidase/efeitos dos fármacos , Monoaminoxidase/metabolismo , Tomografia por Emissão de Pósitrons , Testosterona/administração & dosagem , Testosterona/farmacologia
10.
EMBO Mol Med ; 12(8): e11592, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32609955

RESUMO

Immunity to fungal infections is mediated by cells of the innate and adaptive immune system including Th17 cells. Ca2+ influx in immune cells is regulated by stromal interaction molecule 1 (STIM1) and its activation of the Ca2+ channel ORAI1. We here identify patients with a novel mutation in STIM1 (p.L374P) that abolished Ca2+ influx and resulted in increased susceptibility to fungal and other infections. In mice, deletion of STIM1 in all immune cells enhanced susceptibility to mucosal C. albicans infection, whereas T cell-specific deletion of STIM1 impaired immunity to systemic C. albicans infection. STIM1 deletion impaired the production of Th17 cytokines essential for antifungal immunity and compromised the expression of genes in several metabolic pathways including Foxo and HIF1α signaling that regulate glycolysis and oxidative phosphorylation (OXPHOS). Our study further revealed distinct roles of STIM1 in regulating transcription and metabolic programs in non-pathogenic Th17 cells compared to pathogenic, proinflammatory Th17 cells, a finding that may potentially be exploited for the treatment of Th17 cell-mediated inflammatory diseases.


Assuntos
Cálcio , Células Th17 , Animais , Antifúngicos , Cálcio/metabolismo , Canais de Cálcio/genética , Humanos , Camundongos , Proteínas de Neoplasias , Proteína ORAI1 , Molécula 1 de Interação Estromal/genética , Células Th17/metabolismo
11.
Cereb Cortex ; 30(3): 1345-1356, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-31368487

RESUMO

Univariate analyses of structural neuroimaging data have produced heterogeneous results regarding anatomical sex- and gender-related differences. The current study aimed at delineating and cross-validating brain volumetric surrogates of sex and gender by comparing the structural magnetic resonance imaging data of cis- and transgender subjects using multivariate pattern analysis. Gray matter (GM) tissue maps of 29 transgender men, 23 transgender women, 35 cisgender women, and 34 cisgender men were created using voxel-based morphometry and analyzed using support vector classification. Generalizability of the models was estimated using repeated nested cross-validation. For external validation, significant models were applied to hormone-treated transgender subjects (n = 32) and individuals diagnosed with depression (n = 27). Sex was identified with a balanced accuracy (BAC) of 82.6% (false discovery rate [pFDR] < 0.001) in cisgender, but only with 67.5% (pFDR = 0.04) in transgender participants indicating differences in the neuroanatomical patterns associated with sex in transgender despite the major effect of sex on GM volume irrespective of the self-identification as a woman or man. Gender identity and gender incongruence could not be reliably identified (all pFDR > 0.05). The neuroanatomical signature of sex in cisgender did not interact with depressive features (BAC = 74.7%) but was affected by hormone therapy when applied in transgender women (P < 0.001).


Assuntos
Encéfalo/anatomia & histologia , Identidade de Gênero , Caracteres Sexuais , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Substância Cinzenta/anatomia & histologia , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Análise Multivariada , Tamanho do Órgão , Pessoas Transgênero , Adulto Jovem
12.
Chem Senses ; 45(1): 37-44, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31638640

RESUMO

Evidence suggests that women outperform men in core aspects of odor perception, and sex hormones may play a significant role in moderating this effect. The gender-affirming treatment (GAT) of transgender persons constitutes a powerful natural experiment to study the psychological and behavioral effects of high dosages of cross-sex hormone applications. Therefore, our aim was to investigate the effects of GAT on odor perception in a sample of 131 participants including female and male controls, as well as transmen and transwomen over their first 4 months of gender transition. The Sniffin' Sticks test battery was used to measure odor detection, discrimination, and identification at baseline, as well as 1 and 4 months after the start of GAT. Plasma levels of estradiol, testosterone, and sex hormone-binding globulin were analyzed for each assessment point. Results revealed no significant change of olfactory performance in the two transgender groups compared with female and male controls. There was no significant difference between groups at baseline or any other time point. Neither biological sex, nor gender identity had an influence on odor perception. Moreover, there was no significant correlation between sex hormones and odor perception and between GAT-induced changes in sex hormones and changes in odor perception. Our results indicate that the effects of sex hormones on olfactory performance are subtle, if present at all. However, our results do not preclude hormonal effects on odors not included in the Sniffin' Sticks test battery, such as body odors or odors associated with sex.


Assuntos
Identidade de Gênero , Hormônios Esteroides Gonadais/uso terapêutico , Transtornos do Olfato/tratamento farmacológico , Adulto , Feminino , Hormônios Esteroides Gonadais/sangue , Humanos , Estudos Longitudinais , Masculino , Transtornos do Olfato/sangue , Caracteres Sexuais
13.
Cell Metab ; 29(5): 1104-1118.e6, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30773462

RESUMO

Pathogenic Th17 cells play important roles in many autoimmune and inflammatory diseases. Their function depends on T cell receptor (TCR) signaling and cytokines that activate signal transducer and activator of transcription 3 (STAT3). TCR engagement activates stromal interaction molecule 1 (STIM1) and calcium (Ca2+) influx through Ca2+-release-activated Ca2+ (CRAC) channels. Here, we show that abolishing STIM1 and Ca2+ influx in T cells expressing a hyperactive form of STAT3 (STAT3C) attenuates pathogenic Th17 cell function and inflammation associated with STAT3C expression. Deletion of STIM1 in pathogenic Th17 cells reduces the expression of genes required for mitochondrial function and oxidative phosphorylation (OXPHOS) but enhances reactive oxygen species (ROS) production. STIM1 deletion or inhibition of OXPHOS is associated with a non-pathogenic Th17 gene expression signature and impaired pathogenic Th17 cell function. Our findings establish Ca2+ influx as a critical regulator of mitochondrial function and oxidative stress in pathogenic Th17 cell-mediated multiorgan inflammation.


Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Mitocôndrias/metabolismo , Células Th17/metabolismo , Animais , Inflamação/metabolismo , Camundongos , Camundongos Transgênicos , Fosforilação Oxidativa , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Molécula 1 de Interação Estromal/genética , Transcriptoma/genética
14.
Sci Signal ; 11(561)2018 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-30563862

RESUMO

The earliest intracellular signals that occur after T cell activation are local, subsecond Ca2+ microdomains. Here, we identified a Ca2+ entry component involved in Ca2+ microdomain formation in both unstimulated and stimulated T cells. In unstimulated T cells, spontaneously generated small Ca2+ microdomains required ORAI1, STIM1, and STIM2. Super-resolution microscopy of unstimulated T cells identified a circular subplasmalemmal region with a diameter of about 300 nm with preformed patches of colocalized ORAI1, ryanodine receptors (RYRs), and STIM1. Preformed complexes of STIM1 and ORAI1 in unstimulated cells were confirmed by coimmunoprecipitation and Förster resonance energy transfer studies. Furthermore, within the first second after T cell receptor (TCR) stimulation, the number of Ca2+ microdomains increased in the subplasmalemmal space, an effect that required ORAI1, STIM2, RYR1, and the Ca2+ mobilizing second messenger NAADP (nicotinic acid adenine dinucleotide phosphate). These results indicate that preformed clusters of STIM and ORAI1 enable local Ca2+ entry events in unstimulated cells. Upon TCR activation, NAADP-evoked Ca2+ release through RYR1, in coordination with Ca2+ entry through ORAI1 and STIM, rapidly increases the number of Ca2+ microdomains, thereby initiating spread of Ca2+ signals deeper into the cytoplasm to promote full T cell activation.


Assuntos
Cálcio/metabolismo , Ativação Linfocitária , Proteína ORAI1/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Molécula 2 de Interação Estromal/metabolismo , Linfócitos T/citologia , Animais , Sinalização do Cálcio , Membrana Celular , Células Cultivadas , Feminino , Transferência Ressonante de Energia de Fluorescência , Masculino , Microdomínios da Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Linfócitos T/imunologia , Linfócitos T/metabolismo
15.
Prog Retin Eye Res ; 65: 107-126, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29496590

RESUMO

Autoimmune diseases usually follow a relapsing-remitting or a chronic progressive course. To understand the underlying immunopathogenesis we investigated experimental Lewis rat models displaying both disease types, which were only dependent on the autoantigen peptide used for immunization. Retinal S-Antigen-peptide PDSAg induces chronic, monophasic disease, whilst interphotoreceptor retinoid-binding protein (IRBP)-peptide R14 causes a spontaneously relapsing-remitting course. R14-mediated uveitis can be re-induced by immunization; PDSAg-induced disease is even preventable by prior CFA-injection. T cells with different antigen specificities preferentially infiltrate the eyes from different sites, e.g. choroid or retinal vessels, they remain in the retina after resolution of inflammation for many weeks. The major inflammatory cell populations in the eyes during rat uveitis are CD4+ or CD8+ monocytes/macrophages. Chemokine mutants only suppress PDSAg-mediated EAU, while IFN-α-treatment ameliorated R14-, but worsened PDSAg-induced disease. Comparison of T cells revealed upregulated expression of 26 genes related to various signal transduction pathways upstream and downstream of IFN-γ only in T cells causing relapsing EAU. Intraocular injection of IFN-γ induces synchronized relapses in R14-mediated uveitis, while VEGF-expression of PDSAg-specific T cells causing chronic disease induced chorioretinal neovascularization that is suppressed by anti-CD146 antibody. Intraocular T cells from rat eyes during EAU express IL-17, IFN-γ or IL-10, with dynamic changes of the cell populations during the disease course, differing in both disease types. Immunization of animals with a mixture of both antigens suppressed relapses, indicating a dominance of the monophasic disease. Understanding the exact pathogenesis of both disease courses is key to developing novel therapies for autoimmune diseases.


Assuntos
Doenças Autoimunes/imunologia , Uveíte/imunologia , Animais , Doença Crônica , Citocinas/metabolismo , Modelos Animais de Doenças , Neovascularização Patológica/imunologia , Ratos , Recidiva , Linfócitos T/imunologia
16.
Brain Struct Funct ; 223(1): 321-328, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28819863

RESUMO

Diffusion-weighted imaging (DWI) is used to measure gray matter tissue density and white matter fiber organization/directionality. Recent studies show that DWI also allows for assessing neuroplastic adaptations in the human hypothalamus. To this end, we investigated a potential influence of testosterone replacement therapy on hypothalamic microstructure in female-to-male (FtM) transgender individuals. 25 FtMs were measured at baseline, 4 weeks, and 4 months past treatment start and compared to 25 female and male controls. Our results show androgenization-related reductions in mean diffusivity in the lateral hypothalamus. Significant reductions were observed unilaterally after 1 month and bilaterally after 4 months of testosterone treatment. Moreover, treatment induced increases in free androgen index and bioavailable testosterone were significantly associated with the magnitude of reductions in mean diffusivity. These findings imply microstructural plasticity and potentially related changes in neural activity by testosterone in the adult human hypothalamus and suggest that testosterone replacement therapy in FtMs changes hypothalamic microstructure towards male proportions.


Assuntos
Androgênios/farmacologia , Hipotálamo/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Testosterona/farmacologia , Transexualidade/patologia , Adulto , Androgênios/uso terapêutico , Feminino , Hormônios/sangue , Humanos , Hipotálamo/diagnóstico por imagem , Hipotálamo/patologia , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Testosterona/uso terapêutico , Transexualidade/sangue , Transexualidade/tratamento farmacológico , Substância Branca/diagnóstico por imagem , Substância Branca/efeitos dos fármacos , Adulto Jovem
17.
Nat Commun ; 8: 14714, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28294127

RESUMO

Store-operated Ca2+ entry (SOCE) through Ca2+ release-activated Ca2+ (CRAC) channels is critical for lymphocyte function and immune responses. CRAC channels are hexamers of ORAI proteins that form the channel pore, but the contributions of individual ORAI homologues to CRAC channel function are not well understood. Here we show that deletion of Orai1 reduces, whereas deletion of Orai2 increases, SOCE in mouse T cells. These distinct effects are due to the ability of ORAI2 to form heteromeric channels with ORAI1 and to attenuate CRAC channel function. The combined deletion of Orai1 and Orai2 abolishes SOCE and strongly impairs T cell function. In vivo, Orai1/Orai2 double-deficient mice have impaired T cell-dependent antiviral immune responses, and are protected from T cell-mediated autoimmunity and alloimmunity in models of colitis and graft-versus-host disease. Our study demonstrates that ORAI1 and ORAI2 form heteromeric CRAC channels, in which ORAI2 fine-tunes the magnitude of SOCE to modulate immune responses.


Assuntos
Cálcio/metabolismo , Imunidade , Proteína ORAI2/metabolismo , Linfócitos T/imunologia , Transferência Adotiva , Animais , Proliferação de Células , Colite/imunologia , Colite/patologia , Citocinas/biossíntese , Deleção de Genes , Regulação da Expressão Gênica , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/patologia , Homeostase , Humanos , Imunidade Humoral , Ativação do Canal Iônico , Contagem de Linfócitos , Macrófagos/metabolismo , Camundongos Endogâmicos BALB C , Proteína ORAI1/deficiência , Proteína ORAI1/metabolismo , Proteína ORAI2/deficiência , Multimerização Proteica , Linfócitos T Reguladores/metabolismo , Transplante Homólogo
18.
Neuroimage ; 150: 60-67, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28196668

RESUMO

Sex steroid hormones such as estradiol and testosterone are known to have organizing, as well as activating effects on neural tissue in animals and humans. This study investigated the effects of transgender hormone replacement therapy on white matter microstructure using diffusion tensor imaging. Female-to-male and male-to-female transgender participants were measured at baseline, four weeks and four months past treatment start and compared to female and male controls. We observed androgenization-related reductions in mean diffusivity and increases in fractional anisotropy. We also observed feminization-related increases in mean diffusivity and reductions in fractional anisotropy. In both transgender participants and controls, hormonal fluctuations were correlated with changes in white matter microstructure. Although the present study does not preclude regression to the mean as a potential contributing factor, the results indicate that sex hormones are - at least in part - responsible for white matter variability in the human brain. Studies investigating the effects of sex hormones on adult human brain structure may be an important route for greater understanding of the psychological differences between females and males.


Assuntos
Encéfalo/efeitos dos fármacos , Disforia de Gênero/tratamento farmacológico , Hormônios Esteroides Gonadais/uso terapêutico , Substância Branca/efeitos dos fármacos , Adulto , Imagem de Tensor de Difusão , Feminino , Humanos , Estudos Longitudinais , Masculino
19.
Cell Metab ; 25(3): 698-712, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28132808

RESUMO

Ca2+ signals were reported to control lipid homeostasis, but the Ca2+ channels and pathways involved are largely unknown. Store-operated Ca2+ entry (SOCE) is a ubiquitous Ca2+ influx pathway regulated by stromal interaction molecule 1 (STIM1), STIM2, and the Ca2+ channel ORAI1. We show that SOCE-deficient mice accumulate pathological amounts of lipid droplets in the liver, heart, and skeletal muscle. Cells from patients with loss-of-function mutations in STIM1 or ORAI1 show a similar phenotype, suggesting a cell-intrinsic role for SOCE in the regulation of lipid metabolism. SOCE is crucial to induce mobilization of fatty acids from lipid droplets, lipolysis, and mitochondrial fatty acid oxidation. SOCE regulates cyclic AMP production and the expression of neutral lipases as well as the transcriptional regulators of lipid metabolism, peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), and peroxisome proliferator-activated receptor α (PPARα). SOCE-deficient cells upregulate lipophagy, which protects them from lipotoxicity. Our data provide evidence for an important role of SOCE in lipid metabolism.


Assuntos
Cálcio/metabolismo , Lipólise/genética , Transcrição Gênica , Adenilil Ciclases/metabolismo , Animais , Ácidos Graxos/metabolismo , Células HEK293 , Humanos , Lipase/metabolismo , Gotículas Lipídicas/metabolismo , Camundongos , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/ultraestrutura , Oxirredução , PPAR alfa/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Transdução de Sinais/genética , Regulação para Cima/genética
20.
Hum Brain Mapp ; 37(5): 1738-48, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26876303

RESUMO

Although the sex steroid hormone testosterone is integrally involved in the development of language processing, ethical considerations mostly limit investigations to single hormone administrations. To circumvent this issue we assessed the influence of continuous high-dose hormone application in adult female-to-male transsexuals. Subjects underwent magnetic resonance imaging before and after 4 weeks of testosterone treatment, with each scan including structural, diffusion weighted and functional imaging. Voxel-based morphometry analysis showed decreased gray matter volume with increasing levels of bioavailable testosterone exclusively in Broca's and Wernicke's areas. Particularly, this may link known sex differences in language performance to the influence of testosterone on relevant brain regions. Using probabilistic tractography, we further observed that longitudinal changes in testosterone negatively predicted changes in mean diffusivity of the corresponding structural connection passing through the extreme capsule. Considering a related increase in myelin staining in rodents, this potentially reflects a strengthening of the fiber tract particularly involved in language comprehension. Finally, functional images at resting-state were evaluated, showing increased functional connectivity between the two brain regions with increasing testosterone levels. These findings suggest testosterone-dependent neuroplastic adaptations in adulthood within language-specific brain regions and connections. Importantly, deteriorations in gray matter volume seem to be compensated by enhancement of corresponding structural and functional connectivity. Hum Brain Mapp 37:1738-1748, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Mapeamento Encefálico , Área de Broca/efeitos dos fármacos , Idioma , Testosterona/farmacologia , Área de Wernicke/efeitos dos fármacos , Adulto , Área de Broca/diagnóstico por imagem , Área de Broca/fisiologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/efeitos dos fármacos , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Neuroimagem , Área de Wernicke/diagnóstico por imagem , Área de Wernicke/fisiologia , Substância Branca/diagnóstico por imagem , Substância Branca/efeitos dos fármacos , Adulto Jovem
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