Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
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
2.
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.

3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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
11.
Rev. costarric. salud pública ; 27(1): 42-55, ene.-jun. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-960275

RESUMO

Resumen En 2012 y 2013, se desarrolló en la Escuela de Ciencias Exactas y Naturales (ECEN) de la Universidad Estatal a Distancia (UNED) un Proyecto de Atención y Educación Nutricional (PATENU), para funcionarios con el propósito de realizar modificaciones en sus hábitos alimentarios y prevenir enfermedades crónicas no transmisibles (ECNT). Esta iniciativa surgió de los resultados de una Feria de la Salud realizada en octubre 2011, donde 60% de los participantes presentaron problemas de mal nutrición. Se recolectó la información mediante entrevistas y mediciones antropométricas durante las consultas de seguimiento. En total, participaron en PATENU 69 personas, 55% con sobrepeso u obesidad. 37% de los participantes, realizaron cambios en sus hábitos de alimentación, reduciendo 10% del sobrepeso. Se concluye que las intervenciones nutricionales de corto tiempo, producen resultados positivos.


Abstract In 2012 and 2013, a Project of Nutritional Attention and Education (PATENU) was developed in the School of Exact and Natural Sciences (ECEN) of the State University at Distance (UNED), for officials with the purpose of making changes in their eating habits and prevent chronic non communicable diseases (CNCD). This initiative emerged from the results of a Health Fair held in October 2011, where 60% of the participants presented problems of malnutrition. The information was obtained through interviews and anthropometric measurements during the follow-up consultations. In total, 69 people participated in PATENU, 55% were overweight or obese. 37% of the participants made changes in their eating habits, reducing 10% of overweight. It concluded that short-term nutritional interventions produce positive results.


Assuntos
Educação Alimentar e Nutricional , Sobrepeso/dietoterapia , Ciências da Nutrição , Obesidade , Universidades , Costa Rica
12.
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
13.
Rev. costarric. salud pública ; 25(2): 20-27, jul.-dic. 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-844768

RESUMO

ResumenObjetivo:Capacitar personal de servicios de alimentación comercial sobre el manejo de las grasas residuales, con énfasis en el daño que ocasionan a la salud pública, nutrición del consumidor y al ambiente.Metodología: Se desarrollan tres capacitaciones, que inician con un diagnóstico sobre el manejo de las grasas residuales a una muestra aleatoria de 80 dueños o concesionarios de servicios de alimentación comercial de la Municipalidad de Montes de Oca. Los resultados permiten establecer los contenidos de la capacitación, los cuales se basan en las pautas para freír los alimentos y la eliminación adecuada de la grasa residual.Resultados: Se capacitan 70 personas de 22 negocios. Hay cambios en la frecuencia de uso, filtrado y almacenamientos de los aceites.Conclusión: La educación brindada produjo cambios positivos en favor de la salud, pero se requiere actividades de actualización periódicas.


AbstractObjective:Train personnel of food service business on the management of waste fat, with an emphasis on damage caused to public health, consumer and environment nutrition.Methodology: Develop three training sessions, starting with a diagnosis on the management of waste fats to a random sample of 80 owners or licensees of the municipality of Montes de Oca commercial food service. The results allow to establish the contents of the training, which is based on guidelines for frying food and proper disposal of residual grease.Results:70 people of 22 business are trained. There are changes in the frequency of use, filtering and storage of oils.Conclusion:that provided education produced positive changes in health, but requires periodic update activities.


Assuntos
Restaurantes , Saúde Ambiental/educação , Poluentes Ambientais , Poluição Ambiental/análise , Gorduras/efeitos adversos , Gorduras na Dieta/efeitos adversos , Costa Rica
14.
Materials (Basel) ; 9(6)2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-28773577

RESUMO

Myrcianthes hallii (O. Berg) McVaugh (Myrtaceae) is a plant native to Ecuador, traditionally used for its antiseptic properties. The composition of the hydro-methanolic extract of this plant was determined by submitting it to ultra-high performance liquid chromatography (UHPLC) hyphenated to heated-electrospray ionization mass spectrometry and UV detection. The presence of antimicrobial components prompted us to test the extract against methicillin-resistant and methicillin-susceptible Staphylococcus aureus, multidrug-resistant and susceptible Escherichia coli, Pseudomonas aeruginosa, Enterococcus spp. and Streptococcus pyogenes strains. The chromatographic analysis led to the identification of 38 compounds, including polyphenols and organic acids, and represents the first chemical characterization of this plant. The extract showed modest antibacterial activity against all tested bacteria, with the exception of E. coli which was found to be less sensitive. Whilst methicillin-resistant strains usually display resistance to several drugs, no relevant differences were observed between methicillin-susceptible and resistant strains. Considering its long-standing use in folk medicine, which suggests the relative safety of the plant, and the presence of many known antibacterial polyphenolic compounds responsible for its antibacterial activity, the results show that M. hallii extract could be used as a potential new antiseptic agent. Moreover, new anti-infective biomaterials and nanomaterials could be designed through the incorporation of M. hallii polyphenols. This prospective biomedical application is also discussed.

15.
Biotechnol Prog ; 27(1): 232-40, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21312370

RESUMO

Transglutaminases (TGases) catalyze protein post-translational modification by ε-(γ-glutamyl) links and covalent polyamine conjugation. In plants, this enzyme is poorly characterized and only the maize plastidial TGase gene (tgz) has been cloned. The tgz gene (Patent WWO03102128) had been subcloned and overexpressed in Escherichia coli cells, and the recombinant protein (TGZp) was present mainly in inclusion bodies (IB) fraction. In this work, after overexpression of TGZ15p and SDS-PAGE IB fraction analysis, bands about 65 and 56 kDa were obtained. Western blot, alkylation and MALDI-TOF/TOF analyses indicated that the 56 kDa band corresponded to a truncated sequence from the native TGZ15p (expected MW 65 kDa), by elimination of a chloroplast signal peptide fragment during expression processing. So that large-scale protein production and protein crystallization can be applied, we characterized the TGZ15p enzyme activity in the IB protein fraction, with and without refolding. Results indicate that it presented the biochemical characteristics of other described TGases, showing a certain plant-substrate preference. Solubilization of the IB fraction with Triton X-100 as nondenaturing detergent yielded active TGZ without the need for refolding, giving activity values comparable to those of the refolded protein, indicating that this is a valuable, faster way to obtain TGZ active protein.


Assuntos
Escherichia coli/genética , Corpos de Inclusão/metabolismo , Dobramento de Proteína , Transglutaminases/metabolismo , Zea mays/enzimologia , Western Blotting , Eletroforese em Gel de Poliacrilamida , Microscopia Eletrônica de Transmissão , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Transglutaminases/genética
16.
Biochim Biophys Acta ; 1787(10): 1215-22, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19497298

RESUMO

Transglutaminases (TGases, EC 2.3.2.13) are intra- and extra-cellular enzymes that catalyze post-translational modification of proteins by establishing epsilon-(gamma-glutamyl) links and covalent conjugation of polyamines. In chloroplast it is well established that TGases specifically polyaminylate the light-harvesting antenna of Photosystem (PS) II (LHCII, CP29, CP26, CP24) and therefore a role in photosynthesis has been hypothesised (Della Mea et al. [23] and refs therein). However, the role of TGases in chloroplast is not yet fully understood. Here we report the effect of the over-expression of maize (Zea mays) chloroplast TGase in tobacco (Nicotiana tabacum var. Petit Havana) chloroplasts. The transglutaminase activity in over-expressers was increased 4 times in comparison to the wild-type tobacco plants, which in turn increased the thylakoid associated polyamines about 90%. Functional comparison between Wt tobacco and tgz over-expressers is shown in terms of fast fluorescence induction kinetics, non-photochemical quenching of the singlet excited state of chlorophyll a and antenna heterogeneity of PSII. Both in vivo probing and electron microscopy studies verified thylakoid remodeling. PSII antenna heterogeneity in vivo changes in the over-expressers to a great extent, with an increase of the centers located in grana-appressed regions (PSIIalpha) at the expense of centers located mainly in stroma thylakoids (PSIIbeta). A major increase in the granum size (i.e. increase of the number of stacked layers) with a concomitant decrease of stroma thylakoids is reported for the TGase over-expressers.


Assuntos
Modelos Biológicos , Nicotiana/metabolismo , Tilacoides/metabolismo , Transglutaminases/metabolismo , Zea mays/enzimologia , Fluorescência , Genoma de Planta , Cinética , Complexo de Proteína do Fotossistema II/metabolismo , Pigmentos Biológicos/metabolismo , Poliaminas/metabolismo , Tilacoides/ultraestrutura , Nicotiana/genética , Nicotiana/ultraestrutura
17.
Latacunga; Escuela Nacional de Enfermería; 1993. 85 p. tab, graf.
Monografia em Espanhol | LILACS | ID: lil-352605

RESUMO

El Ecuador, por pertenecer al área Andina, se encuentra en proceso de desarrollo, sisendo enminentemente agrícola. La mayor parte de sus productos se cultivan en la costa y valles profundos de la sierra, posee una cultura invalorable en cuanto a su forma de vida y comportamiento, siendo ésta una de las causas principales para que se transmitan creencias y costumbres arraigadas desde la antihuedad como es la práctica de la medicina tradicional. Nosotros como parte integral del equipo de salud del servicio de Pediatría hemos detectado que la población con mayor frecuencia hace uso de la Medicina Tradicional antes de recibir tratamiento Profesional es la de Chimborazo, aspecto que queremos investigar, estudio que servirá de guía para incorporar la Medicina Profesional a la Tradicional y conjuntamente lograr una recuperación precoz del paciente evitando complicaciones futuras que peligren la vida del niño...


Assuntos
Humanos , Criança , Criança Hospitalizada , Medicina Tradicional , Pediatria , Características Culturais , Matico , Plantago , Fatores Socioeconômicos
18.
Rev. chil. obstet. ginecol ; 54(2): 90-3, 1989. tab
Artigo em Espanhol | LILACS | ID: lil-79236

RESUMO

Puérperas normales ingresadas al Hospital Clínico de la Universidad de Chile, la mayoría de ellas pertenecientes a un estrato socio económico bajo, mostraron un progresivo descenso en los niveles plasmáticos de proteínas totales, albúmina, ß - globulina, IgA e IgM, así como un aumento en los niveles de *1- globulina. Esta tendencia fue observada durante el período de diciembre de 1982 a agosto de 1985, mostrando un patrón plasmático similar al descrito para la desnutrición humana. Los cambios observados en las inmunoglobulinas sugieren un diferente patrón entre aquellas que atraviesan la placenta, de aquellas que no lo hacen, manteniéndose en la madre sólo aquellas que cruzan la placenta


Assuntos
Gravidez , Humanos , Feminino , Proteínas Sanguíneas , Imunoglobulinas/análise , Período Pós-Parto , Chile , Paridade , Desnutrição Proteico-Calórica/sangue , Fatores Socioeconômicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...