Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros












Base de dados
Intervalo de ano de publicação
1.
JCI Insight ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39388276

RESUMO

Sjögren's disease is a chronic autoimmune disease characterized by symptoms of oral and ocular dryness and extra-glandular manifestations. Mouth dryness is not only due to reduced saliva volume but also to alterations in the quality of salivary mucins in these patients. Mucins play a leading role in mucosa hydration and protection, where sulfated and sialylated oligosaccharides retain water molecules at the epithelial surface. The correct localization of glycosyltransferases and sulfotransferases within the Golgi apparatus determines adequate O-glycosylation and sulfation of mucins, which depends on specific golgins that tether enzyme-bearing vesicles. Here, we show that a golgin called Giantin is mislocalized in salivary glands from patients with Sjögren's disease and forms protein complexes with Gal3-O-sulfotransferases (Gal3STs), which change their localization in Giantin knockout and knockdown cells. Our results suggest that Giantin could tether Gal3ST-bearing vesicles and that its altered localization could affect Gal3ST activity, explaining the decreased sulfation of MUC5B observed in salivary glands from patients with Sjögren's disease.

2.
J Autoimmun ; 138: 103037, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37229808

RESUMO

Salivary secretory dysfunction in SS-patients is associated with altered proteostasis, upregulation of ATF6α and components of the ERAD complex, such as SEL1L, and downregulation of XBP-1s and GRP78. Hsa-miR-424-5p is downregulated and hsa-miR-513c-3p is overexpressed in salivary glands from SS-patients. These miRNAs emerged as candidates that could regulate ATF6/SEL1L and XBP-1s/GRP78 levels, respectively. This study aimed to evaluate the effect of IFN-γ on hsa-miR-424-5p and hsa-miR-513c-3p expression and how these miRNAs regulate their targets. In labial salivary glands (LSG) biopsies from 9 SS-patients and 7 control subjects and IFN-γ-stimulated 3D-acini were analyzed. hsa-miR-424-5p and hsa-miR-513c-3p levels were measured by TaqMan assays and their localization by ISH. mRNA, protein levels, and localization of ATF6, SEL1L, HERP, XBP-1s and GRP78 were determined by qPCR, Western blot, or immunofluorescence. Functional and interaction assays were also performed. In LSGs from SS-patients and IFN-γ-stimulated 3D-acini, hsa-miR-424-5p was downregulated and ATF6α and SEL1L were upregulated. ATF6α and SEL1L were decreased after hsa-miR-424-5p overexpression, while ATF6α, SEL1L and HERP increased after hsa-miR-424-5p silencing. Interaction assays revealed that hsa-miR-424-5p targets ATF6α directly. hsa-miR-513c-3p was upregulated and XBP-1s and GRP78 were downregulated. XBP-1s and GRP78 were decreased after hsa-miR-513c-3p overexpression, while increases in XBP-1s and GRP78 were observed after hsa-miR-513c-3p silencing. Furthermore, we determined that hsa-miR-513c-3p targets XBP-1s directly. Significant correlations were found between both miRNA levels and clinical parameters. In conclusion, IFN-γ-dependent hsa-miR-424-5p and hsa-miR-513c-3p levels affect the expression of important factors involved in cellular proteostasis that control secretory function in LSG from SS-patients.


Assuntos
MicroRNAs , Glândulas Salivares , Síndrome de Sjogren , Humanos , Chaperona BiP do Retículo Endoplasmático , Interferon gama/genética , Interferon gama/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas/genética , Proteínas/metabolismo , Glândulas Salivares/metabolismo , Síndrome de Sjogren/genética , Síndrome de Sjogren/metabolismo
3.
Front Med (Lausanne) ; 10: 1118703, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37035319

RESUMO

Introduction: Primary Sjögren's syndrome (SS) is an autoimmune exocrinopathy that affects the structure and function of salivary and lachrymal glands. Labial salivary gland (LSG) acinar cells from SS patients lose cellular homeostasis and experience endoplasmic reticulum and oxidative stress. The integrated cellular stress response (ISR) is an adaptive pathway essential for restoring homeostasis against various stress-inducing factors, including pro-inflammatory cytokines, and endoplasmic reticulum and oxidative stress. ISR activation leads eIF2α phosphorylation, which transiently blocks protein synthesis while allowing the ATF4 expression, which induces a gene expression program that seeks to optimize cellular recovery. PKR, HRI, GCN2, and PERK are the four sentinel stress kinases that control eIF2α phosphorylation. Dysregulation and chronic activation of ISR signaling have pathologic consequences associated with inflammation. Methods: Here, we analyzed the activation of the ISR in LSGs of SS-patients and non-SS sicca controls, determining the mRNA, protein, and phosphorylated-protein levels of key ISR components, as well as the expression of some of ATF4 targets. Moreover, we performed a qualitative characterization of the distribution of ISR components in LSGs from both groups and evaluated if their levels correlate with clinical parameters. Results: We observed that the four ISR sensors are expressed in LSGs of both groups. However, only PKR and PERK showed increased expression and/or activation in LSGs from SS-patients. eIF2α and p-eIF2α protein levels significantly increased in SS-patients; meanwhile components of the PP1c complex responsible for eIF2α dephosphorylation decreased. ATF4 mRNA levels were decreased in LSGs from SS-patients along with hypermethylation of the ATF4 promoter. Despite low mRNA levels, SS-patients showed increased levels of ATF4 protein and ATF4-target genes involved in the antioxidant response. The acinar cells of SS-patients showed increased staining intensity for PKR, p-PKR, p-PERK, p-eIF2α, ATF4, xCT, CHOP, and NRF2. Autoantibodies, focus score, and ESSDAI were correlated with p-PERK/PERK ratio and ATF4 protein levels. Discussion: In summary, the results showed an increased ISR activation in LSGs of SS-patients. The increased protein levels of ATF4 and ATF4-target genes involved in the redox homeostasis could be part of a rescue response against the various stressful conditions to which the LSGs of SS-patients are subjected and promote cell survival.

4.
Cancers (Basel) ; 14(18)2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-36139688

RESUMO

Primary systemic treatment (PST) downsizes the tumor and improves pathological response. The aim of this study is to analyze the feasibility and tolerance of primary concurrent radio−chemotherapy (PCRT) in breast cancer patients. Patients with localized TN/HER2+ tumors were enrolled in this prospective study. Radiation was delivered concomitantly during the first 3 weeks of chemotherapy, and it was based on a 15 fractions scheme, 40.5 Gy/2.7 Gy per fraction to whole breast and nodal levels I-IV. Chemotherapy (CT) was based on Pertuzumab−Trastuzumab−Paclitaxel followed by anthracyclines in HER2+ and CBDCA-Paclitaxel followed by anthracyclines in TN breast cancers patients. A total of 58 patients were enrolled; 25 patients (43%) were TN and 33 patients HER2+ (57%). With a median follow-up of 24.2 months, 56 patients completed PCRT and surgery. A total of 35 patients (87.5%) achieved >90% loss of invasive carcinoma cells in the surgical specimen. The 70.8% and the 53.1% of patients with TN and HER-2+ subtype, respectively, achieved complete pathological response (pCR). This is the first study of concurrent neoadjuvant treatment in breast cancer in which three strategies were applied simultaneously: fractionation of RT (radiotherapy) in 15 sessions, adjustment of CT to tumor phenotype and local planning by PET. The pCR rates are encouraging.

5.
Oral Health Prev Dent ; 20(1): 321-330, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35866678

RESUMO

PURPOSE: To present updated information on odontogenic keratocyst (OKC) classification, etiology, genetic and molecular alterations, epidemiology, clinical presentation, radiographic characteristics, histological and immune histochemical features, differential diagnosis, treatment, and controversies, as well as a literature review of case frequencies in different countries. MATERIALS AND METHODS: Studies were selected using the key words 'odontogenic keratocyst,' 'odontogenic cysts,' 'odontogenic keratocyst and clinical study'. Full-text papers were reviewed on the basis of the inclusion and exclusion criteria. The literature search aimed to find articles that would show the frequency of OKC, dentigerous cyst, radicular cyst, and other cysts. RESULTS: OKC presents local aggression and high recurrence; therefore, a better understanding of its clinical characteristics and the genetic and molecular factors involved in this peculiar and controversial lesion is required. It is always essential to discuss treatment alternatives. Although OKC is an entity with a high recurrence, aggressive treatment is not advisable in all cases because factors such as commitment to anatomical structures and possible complications should be considered. However, periodic radiographic controls are advised. CONCLUSION: To reduce the high number of present cases worldwide, it is important to improve knowledge on this pathology so that accurate diagnoses can be achieved and appropriate treatment can be provided. OKC presents local aggression and high recurrence; therefore, a better understanding is needed of the clinical characteristics and genetic and molecular factors involved in OKC. Furthermore, it is always essential to discuss treatment alternatives.


Assuntos
Cistos Odontogênicos , Humanos , Cistos Odontogênicos/diagnóstico por imagem , Cistos Odontogênicos/epidemiologia , Cistos Odontogênicos/patologia
6.
Front Immunol ; 13: 870094, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432384

RESUMO

MicroRNAs (miRNAs) are small non-coding RNAs (sRNA), that alter gene expression by binding to target messenger RNAs (mRNAs) and repressing translation. Dysregulated miRNA expression has been implicated in the pathogenesis of autoimmune diseases such as Sjögren's syndrome (SS). The aim of this study was to characterize the global profile of sRNAs in labial salivary glands (LSG) from SS-patients and to validate potential miRNA candidates implicated in glandular inflammation. LSG from 21 SS-patients and 9 sicca controls were analyzed. A global next generation sequencing (NGS)-based sRNA profiling approach was employed to identify direct targets whereby differentially expressed miRNAs were predicted using bioinformatics tools. miRNA levels were validated by TaqMan and target mRNA levels were determined by quantitative real-time PCR. We also performed in vitro assays using recombinant TNF-α. NGS shows that ~30% of sRNAs were miRNAs. In comparison with samples from sicca controls, four miRNAs were found differentially expressed in LSG from SS-patients with low focus score (LFS) and 18 from SS-patients with high focus score (HFS). The miRNA with the most significant changes identified by NGS was hsa-miR-181d-5p and downregulation was confirmed by TaqMan analysis. Levels of TNF-α mRNA, a direct target of hsa-miR-181d-5p, were significantly increased and negatively correlated with hsa-miR-181d-5p presence. Moreover, positive correlations between TNF-α transcript levels, focus score, ESSDAI, and autoantibody levels were also detected. Furthermore, TNF-α stimulation decreased hsa-miR-181d-5p levels in vitro. Downregulation of hsa-miR-181d-5p in LSG from SS-patients could contribute to the glandular pro-inflammatory environment by deregulation of its direct target TNF-α. Further dissection of the pathophysiological mechanisms underlying the hsa-miR-181d-5p-mediated action in inflammatory conditions could be useful to evaluate the benefits of increasing hsa-miR-181d-5p levels for restoration of salivary gland epithelial cell architecture and function.


Assuntos
MicroRNAs , Síndrome de Sjogren , Regulação para Baixo , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Mensageiro/genética , Síndrome de Sjogren/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2230-2233, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891730

RESUMO

Health education is essential for type 1 diabetic patients to actively participate in the decision-making process about their disease. Under the framework of the INCAP project, a mobile application has been designed and developed with an easy-to-use interface for type 1 diabetic patients to improve their empowerment, activation and thus their self-control and improvement of their treatment adherence.


Assuntos
Diabetes Mellitus Tipo 1 , Empoderamento , Aplicativos Móveis , Humanos
8.
Front Immunol ; 12: 685837, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149728

RESUMO

Sjögren's syndrome (SS) is an autoimmune disease that mainly affects salivary glands (SG) and is characterized by overactivation of the type I interferon (IFN) pathway. Type I IFNs can decrease the levels of hsa-miR-145-5p, a miRNA with anti-inflammatory roles that is downregulated in SG from SS-patients. Two relevant targets of hsa-miR-145-5p, mucin 1 (MUC1) and toll-like receptor 4 (TLR4) are overexpressed in SS-patients and contribute to SG inflammation and dysfunction. This study aimed to evaluate if hsa-miR-145-5p modulates MUC1 and TLR4 overexpression in SG from SS-patients in a type I IFN dependent manner. Labial SG (LSG) biopsies from 9 SS-patients and 6 controls were analyzed. We determined hsa-miR-145-5p levels by TaqMan assays and the mRNA levels of MUC1, TLR4, IFN-α, IFN-ß, and IFN-stimulated genes (MX1, IFIT1, IFI44, and IFI44L) by real time-PCR. We also performed in vitro assays using type I IFNs and chemically synthesized hsa-miR-145-5p mimics and inhibitors. We validated the decreased hsa-miR-145-5p levels in LSG from SS-patients, which inversely correlated with the type I IFN score, mRNA levels of IFN-ß, MUC1, TLR4, and clinical parameters of SS-patients (Ro/La autoantibodies and focus score). IFN-α or IFN-ß stimulation downregulated hsa-miR-145-5p and increased MUC1 and TLR4 mRNA levels. Hsa-miR-145-5p overexpression decreased MUC1 and TLR4 mRNA levels, while transfection with a hsa-miR-145-5p inhibitor increased mRNA levels. Our findings show that type I IFNs decrease hsa-miR-145-5p expression leading to upregulation of MUC1 and TLR4. Together, this suggests that type I interferon-dependent hsa-miR-145-5p downregulation contributes to the perpetuation of inflammation in LSG from SS-patients.


Assuntos
Interferon Tipo I/metabolismo , MicroRNAs/metabolismo , Mucina-1/metabolismo , Síndrome de Sjogren/metabolismo , Receptor 4 Toll-Like/metabolismo , Adulto , Regulação para Baixo , Feminino , Humanos , Inflamação/metabolismo , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Mucina-1/genética , Glândulas Salivares Menores/metabolismo , Síndrome de Sjogren/genética , Receptor 4 Toll-Like/genética , Adulto Jovem
9.
Autoimmun Rev ; 20(8): 102867, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34118452

RESUMO

Relevant reviews highlight the association between dysfunctional mitochondria and inflammation, but few studies address the contribution of mitochondria and mitochondria-endoplasmic reticulum (ER) contact sites (MERCs) to cellular homeostasis and inflammatory signaling. The present review outlines the important role of mitochondria in cellular homeostasis and how dysfunctional mitochondrion can release and misplace mitochondrial components (cardiolipin, mitochondrial DNA (mtDNA), and mitochondrial formylated peptides) through multiple mechanisms. These components can act as damage-associated molecular patterns (DAMPs) and induce an inflammatory response via pattern recognition receptors (PRRs). Accumulation of damaged ROS-generating mitochondria, accompanied by the release of mitochondrial DAMPs, can activate PRRs such as the NLRP3 inflammasome, TLR9, cGAS/STING, and ZBP1. This process would explain the chronic inflammation that is observed in autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), type I diabetes (T1D), and Sjögren's syndrome. This review also provides a comprehensive overview of the importance of MERCs to mitochondrial function and morphology, cellular homeostasis, and the inflammatory response. MERCs play an important role in calcium homeostasis by mediating the transfer of calcium from the ER to the mitochondria and thereby facilitating the production of ATP. They also contribute to the synthesis and transfer of phospholipids, protein folding in the ER, mitochondrial fission, mitochondrial fusion, initiation of autophagosome formation, regulation of cell death/survival signaling, and regulation of immune responses. Therefore, alterations within MERCs could increase inflammatory signaling, modulate ER stress responses, cell homeostasis, and ultimately, the cell fate. This study shows severe ultrastructural alterations of mitochondria in salivary gland cells from Sjögren's syndrome patients for the first time, which could trigger alterations in cellular bioenergetics. This finding could explain symptoms such as fatigue and malfunction of the salivary glands in Sjögren's syndrome patients, which would contribute to the chronic inflammatory pathology of the disease. However, this is only a first step in solving this complex puzzle, and several other important factors such as changes in mitochondrial morphology, functionality, and their important contacts with other organelles require further in-depth study. Future work should focus on detecting the key milestones that are related to inflammation in patients with autoimmune diseases, such as Sjögren´s syndrome.


Assuntos
Síndrome de Sjogren , DNA Mitocondrial/metabolismo , Retículo Endoplasmático/metabolismo , Humanos , Inflamação/metabolismo , Mitocôndrias
10.
Rheumatology (Oxford) ; 60(4): 1951-1962, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216905

RESUMO

OBJECTIVE: Altered homeostasis of salivary gland (SG) epithelial cells in Sjögren's syndrome (SS) could be the initiating factor that leads to inflammation, secretory dysfunction and autoimmunity. Autophagy is an important homeostatic mechanism, whose deficiency is associated with inflammation and accumulation of Janus kinase (JAK)-signal transducer and activator of transcription (STAT) components. We aimed to evaluate whether autophagy is altered in labial SG (LSG) epithelial cells from primary SS (pSS) patients and whether this contributes to inflammation through the JAK-STAT pathway. Furthermore, we investigated the anti-inflammatory effect of the JAK inhibitor tofacitinib in autophagy-deficient (ATG5 knockdown) three-dimensional (3D)-acini. METHODS: We analysed LSG biopsies from 12 pSS patients with low focus score and 10 controls. ATG5-deficient 3D-acini were generated and incubated with IL-6 in the presence or absence of tofacitinib. Autophagy markers, pro-inflammatory cytokine expression, and JAK-STAT pathway activation were evaluated by PCR or western blot, along with correlation analyses between the evaluated markers and clinical parameters. RESULTS: LSG from pSS patients showed increased p62 and decreased ATG5 expression, correlating negatively with increased activation of JAK-STAT pathway components (pSTAT1 and pSTAT3). Increased expression of STAT1 and IL-6 correlated with EULAR Sjögren's syndrome disease activity index and the presence of anti-Ro antibodies. ATG5-deficient 3D-acini reproduced the findings observed in LSG from pSS patients, showing increased expression of pro-inflammatory markers such as IL-6, which was reversed by tofacitinib. CONCLUSION: Decreased expression of ATG5 in LSG epithelial cells from pSS patients possibly contributes to increased inflammation associated with JAK-STAT pathway activation, as evidenced in ATG5-deficient 3D-acini. Interestingly, these results suggest that tofacitinib could be used as an anti-inflammatory agent in pSS patients.


Assuntos
Autofagia/efeitos dos fármacos , Interleucina-6/metabolismo , Piperidinas/farmacologia , Pirimidinas/farmacologia , Adolescente , Adulto , Idoso , Western Blotting , Estudos de Casos e Controles , Feminino , Imunofluorescência , Humanos , Interleucina-6/antagonistas & inibidores , Janus Quinases/metabolismo , Masculino , Pessoa de Meia-Idade , Piperidinas/uso terapêutico , Pirimidinas/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Transcrição STAT/metabolismo , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Síndrome de Sjogren , Adulto Jovem
11.
Rheumatology (Oxford) ; 59(4): 742-753, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31377809

RESUMO

OBJECTIVES: Xerostomia in SS patients has been associated with low quality and quantity of salivary mucins, which are fundamental for the hydration and protection of the oral mucosa. The aim of this study was to evaluate if cytokines induce aberrant mucin expression and whether tauroursodeoxycholic acid (TUDCA) is able to counteract such an anomaly. METHODS: Labial salivary glands from 16 SS patients and 15 control subjects, as well as 3D acini or human submandibular gland cells stimulated with TNF-α or IFN-γ and co-incubated with TUDCA, were analysed. mRNA and protein levels of Mucin 1 (MUC1) and MUC7 were determined by RT-qPCR and western blot, respectively. Co-immunoprecipitation and immunofluorescence assays for mucins and GRP78 [an endoplasmic reticulum (ER)-resident protein] were also performed. mRNA levels of RelA/p65 (nuclear factor-κB subunit), TNF-α, IL-1ß, IL-6, SEL1L and EDEM1 were determined by RT-qPCR, and RelA/p65 localization was evaluated by immunofluorescence. RESULTS: MUC1 is overexpressed and accumulated in the ER of labial salivary gland from SS patients, while MUC7 accumulates throughout the cytoplasm of acinar cells; however, MUC1, but not MUC7, co-precipitated with GRP78. TUDCA diminished the overexpression and aberrant accumulation of MUC1 induced by TNF-α and IFN-γ, as well as the nuclear translocation of RelA/p65, together with the expression of inflammatory and ER stress markers in 3D acini. CONCLUSION: Chronic inflammation alters the secretory process of MUC1, inducing ER stress and affecting the quality of saliva in SS patients. TUDCA showed anti-inflammatory properties decreasing aberrant MUC1 accumulation. Further studies are necessary to evaluate the potential therapeutic effect of TUDCA in restoring glandular homeostasis in SS patients.


Assuntos
Células Acinares/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Mucina-1/efeitos dos fármacos , Glândulas Salivares Menores/efeitos dos fármacos , Síndrome de Sjogren/metabolismo , Glândula Submandibular/efeitos dos fármacos , Ácido Tauroquenodesoxicólico/farmacologia , Xerostomia/metabolismo , Células Acinares/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Células Cultivadas , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/genética , Feminino , Proteínas de Choque Térmico/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Imunoprecipitação , Técnicas In Vitro , Interferon gama/farmacologia , Interleucina-1beta/efeitos dos fármacos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Mucina-1/genética , Mucina-1/metabolismo , Mucinas/efeitos dos fármacos , Mucinas/genética , Mucinas/metabolismo , Proteínas/efeitos dos fármacos , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Glândulas Salivares Menores/metabolismo , Proteínas e Peptídeos Salivares/efeitos dos fármacos , Proteínas e Peptídeos Salivares/genética , Proteínas e Peptídeos Salivares/metabolismo , Síndrome de Sjogren/genética , Glândula Submandibular/citologia , Glândula Submandibular/metabolismo , Fator de Transcrição RelA/efeitos dos fármacos , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Xerostomia/genética
12.
J Autoimmun ; 97: 88-99, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30391023

RESUMO

Sjögren's syndrome (SS) is an autoimmune exocrinopathy associated with severe secretory alterations by disruption of the glandular architecture integrity, which is fundamental for a correct function and localization of the secretory machinery. Syt-1, PI(4,5)P2 and Ca2+ are significant factors controlling exocytosis in different secretory cells, the Ca2+ role being the most studied. Salivary acinar cells from SS-patients show a defective agonist-regulated intracellular Ca2+ release together with a decreased IP3R expression level, and this condition may explain a reduced water release. However, there are not reports where Syt-1, PI(4,5)P2 and Ca2+ in acinar cells of SS patients had been studied. In the present study, we analyzed the expression and/or localization of Syt-1 and PI(4,5)P2 in acinar cells of labial salivary gland biopsies from SS-patients and control individuals. Also, we evaluated whether the overexpression of Syt-1 and the loss of cell polarity induced by TNF-α or loss of interaction between acinar cell and basal lamina, alters directionality of the exocytosis process, Ca2+ signaling and α-amylase secretion in a 3D-acini model stimulated with cholinergic or ß-adrenergic agonists. In addition, the correlation between Syt-1 protein levels and clinical parameters was evaluated. The results showed an increase of Syt-1 mRNA and protein levels, and a high number of co-localization points of Syt-1/STX4 and PI(4,5)P2/Ezrin in the acinar basolateral region of LSG from SS-patients. With regard to 3D-acini, Syt-1 overexpression increased exocytosis in the apical pole compared to control acini. TNF-α stimulation increased exocytic events in the basal pole, which was further enhanced by Syt-1 overexpression. Additionally, altered acinar cell polarity affected Ca2+ signaling and amylase secretion. Overexpression of Syt-1 was associated with salivary gland alterations revealing that the secretory dysfunction in SS-patients is linked to altered expression and/or localization of secretory machinery components together with impaired epithelial cell polarity. These findings provide a novel insight on the pathological mechanism implicated in ectopic secretory products to the extracellular matrix of LSG from SS-patients, which might initiate inflammation.


Assuntos
Expressão Gênica , Glândulas Salivares/metabolismo , Síndrome de Sjogren/etiologia , Síndrome de Sjogren/metabolismo , Sinaptotagmina I/genética , Adulto , Biomarcadores , Biópsia , Cálcio/metabolismo , Sinalização do Cálcio , Suscetibilidade a Doenças , Feminino , Glicosilação , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Glândulas Salivares/patologia , Transdução de Sinais , Síndrome de Sjogren/diagnóstico , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
13.
Autoimmun Rev ; 17(8): 796-808, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29890347

RESUMO

For many years, researchers in the field of autoimmunity have focused on the role of the immune components in the etiopathogenesis of autoimmune diseases. However, some studies have demonstrated the importance of target tissues in their pathogenesis and the breach of immune tolerance. The immune system as well as target tissue cells (plasmatic, ß-pancreatic, fibroblast-like synoviocytes, thyroid follicular and epithelial cells of the lachrymal glands, salivary glands, intestine, bronchioles and renal tubules) share the characteristic of secretory cells with an extended endoplasmic reticulum (ER). The function of these cells depends considerably on a normal ER function and calcium homeostasis, so they can produce and secrete their main components, which include glycoproteins involved in antigenic presentation such as major histocompatibility complex (MHC) class I and II. All these proteins are synthesized and modified in the ER, and for this reason disturbances in the normal functions of this organelle such as protein folding, protein quality control, calcium homeostasis and redox balance, promote accumulation of unfolded or misfolded proteins, a condition known as ER stress. Autoimmune diseases are characterized by inflammation, which has been associated with an ER stress condition. Interestingly, patients with these diseases contain circulating auto-antibodies against chaperone proteins (such as Calnexin and GRP94), thus affecting the folding and assembly of MHC class I and II glycoproteins and their loading with peptide. The main purpose of this article is to review the involvement of the protein quality control and unfolded protein response (UPR) in the ER protein homeostasis (proteostasis) and their alterations in autoimmune diseases. In addition, we describe the interaction between ER stress and inflammation and evidences are shown of how autoimmune diseases are associated with an ER stress condition, with a special emphasis on the second most prevalent autoimmune rheumatic disease, Sjögren's syndrome.


Assuntos
Autoimunidade , Estresse do Retículo Endoplasmático , Dobramento de Proteína , Proteínas/metabolismo , Síndrome de Sjogren/fisiopatologia , Resposta a Proteínas não Dobradas , Animais , Retículo Endoplasmático/metabolismo , Humanos , Proteínas/química
14.
Clin Immunol ; 196: 85-96, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29894742

RESUMO

Here, we determined the 5-hydroxymethylcytosine (5hmC), 5-methylcytosine (5mC), Ten Eleven Translocation (TETs), and DNA methyltransferases (DNMTs) levels in epithelial and inflammatory cells of labial salivary glands (LSG) from Sjögren's syndrome (SS)-patients and the effect of cytokines on HSG cells. LSG from SS-patients, controls and HSG cells incubated with cytokines were analysed. Levels of 5mC, 5hmC, DNMTs, TET2 and MeCP2 were assessed by immunofluorescence. In epithelial cells from SS-patients, an increase in TET2, 5hmC and a decrease in 5mC and MeCP2 were observed, additionally, high levels of 5mC and DNMTs and low levels of 5hmC were detected in inflammatory cells. Cytokines increased TET2 and 5hmC and decreased 5mC levels. Considering that the TET2 gene.promoter contains response elements for transcription factors activated by cytokines, together to in vitro results suggest that changes in DNA hydroxymethylation, resulting from altered levels of TET2 are likely to be relevant in the Sjögren's syndrome etiopathogenesis.


Assuntos
5-Metilcitosina/análogos & derivados , DNA (Citosina-5-)-Metiltransferases/genética , Proteínas de Ligação a DNA/genética , Proteína 2 de Ligação a Metil-CpG/genética , Proteínas Proto-Oncogênicas/genética , Glândulas Salivares Menores/metabolismo , Síndrome de Sjogren/genética , 5-Metilcitosina/metabolismo , Adulto , Idoso , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Citocinas/imunologia , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , DNA Metiltransferase 3A , Proteínas de Ligação a DNA/imunologia , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/genética , Dioxigenases/imunologia , Dioxigenases/metabolismo , Epigênese Genética , Feminino , Expressão Gênica , Regulação da Expressão Gênica , Humanos , Inflamação/genética , Inflamação/metabolismo , Lábio , Masculino , Proteína 2 de Ligação a Metil-CpG/metabolismo , Pessoa de Meia-Idade , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/imunologia , Oxigenases de Função Mista/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/imunologia , Proteínas Proto-Oncogênicas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Glândulas Salivares Menores/citologia , Glândulas Salivares Menores/imunologia , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/metabolismo , Adulto Jovem , DNA Metiltransferase 3B
15.
Rheumatology (Oxford) ; 57(6): 1021-1032, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29534223

RESUMO

Objectives: Labial salivary glands (LSGs) of SS patients show alterations related to endoplasmic reticulum stress. Glandular dysfunction could be partly the consequence of an altered inositol-requiring enzyme 1α (IRE1α)/X box-binding protein 1 (XBP-1) signalling pathway of the unfolded protein response, which then regulates genes involved in biogenesis of the secretory machinery. This study aimed to determine the expression, promoter methylation and localization of the IRE1α/XBP-1 pathway components in LSGs of SS patients and also their expression induced by IFN-γ in vitro. Methods: IRE1α, XBP-1 and glucose-regulated protein 78 (GRP78) mRNA and protein levels were measured by qPCR and western blot, respectively, in LSGs of SS patients (n = 47) and control subjects (n = 37). Methylation of promoters was evaluated by methylation-sensitive high resolution melting, localization was analysed by immunofluorescence and induction of the IRE1α/XBP-1 pathway components by IFN-γ was evaluated in 3D acini. Results: A significant decrease of IRE1α, XBP-1u, XBP-1s, total XBP-1 and GRP78 mRNAs was observed in LSGs of SS patients, which was correlated with increased methylation levels of their respective promoters, and consistently the protein levels for IRE1α, XBP-1s and GRP78 were observed to decrease. IFN-γ decreased the mRNA and protein levels of XBP-1s, IRE1α and GRP78, and increased methylation of their promoters. Significant correlations were also found between IRE1α/XBP-1 pathway components and clinical parameters. Conclusion: Decreased mRNA levels for IRE1α, XBP-1 and GRP78 can be partially explained by hypermethylation of their promoters and is consistent with chronic endoplasmic reticulum stress, which may explain the glandular dysfunction observed in LSGs of SS patients. Additionally, glandular stress signals, including IFN-γ, could modulate the expression of the IRE1α/XBP-1 pathway components.


Assuntos
Endorribonucleases/genética , Regulação da Expressão Gênica , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , Glândulas Salivares/fisiopatologia , Síndrome de Sjogren/genética , Proteína 1 de Ligação a X-Box/genética , Adulto , Idoso , Western Blotting , Metilação de DNA , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Endorribonucleases/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases/biossíntese , Glândulas Salivares/metabolismo , Transdução de Sinais , Síndrome de Sjogren/metabolismo , Síndrome de Sjogren/patologia , Proteína 1 de Ligação a X-Box/biossíntese , Adulto Jovem
17.
Clin Rev Allergy Immunol ; 52(1): 125-132, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28004375

RESUMO

Gorham-Stout disease (GSD) is a rare condition of osteolysis with excessive lymphangiogenesis within bone tissue. The etiology of this condition remains unknown but seems to affect mainly children and young adults of both genders all over the world. Unfortunately, there is no standardized method for diagnosis; however, histopathology remains as the gold standard. This condition is often misdiagnosed due to its varying clinical presentations from case-to-case. Here, we report the case of an 8-year-old girl who presented with chronic mandibular pain during mastication and received multiple antibiotic treatment due to infectious origin suspicion. After integrating information from clinical manifestations, radiographic, laboratory, and histopathology information, she was diagnosed with GSD. Additionally, due to the lack of literature with respect to insights into biological mechanisms and standardized treatment for this condition, we underwent a literature revision to provide information related to activation of cells from the immune system, such as macrophages, T-cells, and dendritic cells, and their contribution to the lymphangiogenesis, angiogenesis, and osteoclastogenic process in GSD. It is important to consider these mechanisms in patients with GSD, especially since new studies performed in earlier stages are required to confirm their use as novel diagnostic tools and find new possibilities for treatment.


Assuntos
Osteólise Essencial/patologia , Criança , Feminino , Humanos , Mandíbula/anormalidades , Osteólise Essencial/diagnóstico
18.
J Autoimmun ; 75: 68-81, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27461470

RESUMO

Salivary gland (SG) acinar-cells are susceptible to endoplasmic reticulum (ER) stress related to their secretory activity and the complexity of synthesized secretory products. SGs of Sjögren's syndrome patients (SS)-patients show signs of inflammation and altered proteostasis, associated with low IRE1α/XBP-1 pathway activity without avert increases in apoptosis. Acinar-cells may avoid apoptosis by activation of the ATF6α pathway and ER-associated protein degradation (ERAD). The aim of this study was to evaluate the role of pro-inflammatory cytokines in ATF6α pathway/ERAD activation and cell viability in labial salivary glands (LSG) of SS-patients. In biopsies from SS-patients increased ATF6α signaling pathway activity, as evidenced by generation of the ATF6f cleavage fragment, and increased expression of ERAD machinery components, such as EDEM1, p97, SEL1L, gp78, UBE2J1, UBE2G2, HERP and DERLIN1, were observed compared to controls. Alternatively, for pro- (active-caspase-3) and anti-apoptotic (cIAP2) markers no significant difference between the two experimental groups was detected. Increased presence of ATF6f and ERAD molecules correlated significantly with increased expression of pro-inflammatory cytokines. These observations were corroborated in vitro in 3D-acini treated with TNF-α and/or IFN-γ, where an increase in the expression and activation of the ATF6α sensor and ERAD machinery components was detected under ER stress conditions, while changes in cell viability and caspase-3 activation were not observed. Cytokine stimulation protected cells from death when co-incubated with an ERAD machinery inhibitor. Alternatively, when cytokines were eliminated from the medium prior to ERAD inhibition, cell death increased, suggesting that the presence of pro-inflammatory cytokines in the medium is essential to maintain cell viability. In conclusion, the ATF6α pathway and the ERAD machinery are active in LSG of SS-patients. Both were also activated by TNF-α and IFN-γ in vitro in 3D-acini and aided in preventing apoptosis. IFN-γ levels were elevated in SS-patients and UPR responses triggered in vitro by this cytokine closely matched those observed in LSG from SS-patients, suggesting that cytokines may induce ER stress.


Assuntos
Fator 6 Ativador da Transcrição/imunologia , Citocinas/imunologia , Degradação Associada com o Retículo Endoplasmático/imunologia , Glândulas Salivares/imunologia , Síndrome de Sjogren/imunologia , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Adolescente , Adulto , Apoptose/imunologia , Apoptose/efeitos da radiação , Western Blotting , Caspase 3/imunologia , Caspase 3/metabolismo , Citocinas/metabolismo , Citocinas/farmacologia , Degradação Associada com o Retículo Endoplasmático/genética , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/imunologia , Feminino , Expressão Gênica/imunologia , Humanos , Imuno-Histoquímica , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/farmacologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Pessoa de Meia-Idade , Proteínas/genética , Proteínas/imunologia , Proteínas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Glândulas Salivares/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Síndrome de Sjogren/genética , Síndrome de Sjogren/metabolismo , Adulto Jovem
19.
Oral Maxillofac Surg ; 20(1): 1-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26556782

RESUMO

The purpose of the present article was to present a clinical case of an 11-year-old girl with peripheral ossifying fibroma (POF). Additionally, after performing a literature review, we identified clinical information that occurs more frequently in association with POF, such evidence would help professionals in yielding a specific diagnosis and tailor a more specific therapeutic approach with the objective to decrease morbidities' associated with POF. This lesion represents the third most common lesion of all localized reactive hyperplastic lesions. Clinical aspects related to this pathology include the fact that it occurs most frequently in women between the first and second decades of life. It affects anterior maxillary region and interferes with normal functioning of this anatomical structure. After conducting the literature search, we found that it can also be presented in a considerable number of males with pain and hyperemia being the most common clinical manifestations. We found that often clinical cases are presented with incomplete information. It is important that in order to get to a consensus with respect to updates about information related to this lesion, new case series that include complete clinical information, radiographic analysis, and histopathology tests could be presented.


Assuntos
Neoplasias Ósseas/diagnóstico , Fibroma Ossificante/diagnóstico , Neoplasias Maxilares/diagnóstico , Biópsia , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Criança , Diagnóstico Diferencial , Feminino , Fibroma Ossificante/patologia , Fibroma Ossificante/cirurgia , Humanos , Masculino , Maxila/patologia , Maxila/cirurgia , Neoplasias Maxilares/patologia , Neoplasias Maxilares/cirurgia , Radiografia Panorâmica , Tomografia Computadorizada por Raios X
20.
PLoS One ; 10(8): e0136313, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26308941

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid-ß (Aß) peptide. We have previously shown that the compound tetrahydrohyperforin (IDN5706) prevents accumulation of Aß species in an in vivo model of AD, however the mechanism that explains this reduction is not well understood. We show herein that IDN5706 decreases the levels of ER degradation enhancer, mannosidase alpha-like 1 (EDEM1), a key chaperone related to endoplasmic-reticulum-associated degradation (ERAD). Moreover, we observed that low levels of EDEM1 correlated with a strong activation of autophagy, suggesting a crosstalk between these two pathways. We observed that IDN5706 perturbs the glycosylation and proteolytic processing of the amyloid precursor protein (APP), resulting in the accumulation of immature APP (iAPP) in the endoplasmic reticulum. To investigate the contribution of autophagy, we tested the effect of IDN5706 in Atg5-depleted cells. We found that depletion of Atg5 enhanced the accumulation of iAPP in response to IDN5706 by slowing down its degradation. Our findings reveal that IDN5706 promotes degradation of iAPP via the activation of Atg5-dependent autophagy, shedding light on the mechanism that may contribute to the reduction of Aß production in vivo.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Autofagia/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Floroglucinol/análogos & derivados , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Terpenos/farmacologia , Precursor de Proteína beta-Amiloide/genética , Animais , Proteína 5 Relacionada à Autofagia , Western Blotting , Células Cultivadas , Retículo Endoplasmático/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Imunofluorescência , Glicosilação/efeitos dos fármacos , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Rim/citologia , Rim/efeitos dos fármacos , Rim/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia de Fluorescência , Proteínas Associadas aos Microtúbulos/genética , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Floroglucinol/farmacologia , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...