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<p><b>BACKGROUND</b>Mucocutaneous lesions are common features of primary Sjögren's syndrome (pSS), but only a few studies have focused on them. To demonstrate the profile of mucocutaneous lesions of pSS and further explore their potential clinical significance, we performed a cross-sectional study on 874 patients.</p><p><b>METHODS</b>Demographic data, clinical manifestations, and laboratory results of 874 pSS patients were collected. Patients were divided into two groups according to the presence of mucocutaneous lesions. Differences in primary symptoms and systemic impairments between the two groups were analyzed. Results of laboratory tests were also compared after excluding those who had taken corticosteroid from both groups. One-year follow-up was done, and occurrences of various new complications were compared.</p><p><b>RESULTS</b>Among the 874 pSS patients, 181 patients had mucocutaneous lesions, accounting for 20.7%. Multiple mucocutaneous manifestations were displayed, and the top four most common types of lesions were purpuric eruptions (39.8%), urticaria (23.8%), Raynaud's phenomenon (14.9%), and angular stomatitis (9.9%). Incidences of pulmonary interstitial fibrosis, pulmonary bullae, leukopenia, and anemia were significantly higher among patients with mucocutaneous lesions (P < 0.05). Increase in IgG and decrease in C4 among patients with mucocutaneous lesions displayed statistical significance after excluding patients from both groups who had taken corticosteroid (P < 0.05). After one-year follow-up, patients with mucocutaneous lesions presented a slightly higher incidence of new complications compared to those without.</p><p><b>CONCLUSIONS</b>Mucocutaneous manifestations of pSS patients were common and diverse. Patients with mucocutaneous manifestations had more systemic damages, higher level of IgG, and lower level of serum C4, suggesting a higher activity of the primary disease.</p>
RESUMO
<p><b>OBJECTIVE</b>To investigate the underlying mechanism of the protective effects of resveratrol on oxidant-induced mitochondrial damage in embryonic rat cardiomyocytes.</p><p><b>METHODS</b>H9c2 cells, a permanent cell line derived from embryonic rat cardiac tissue, and then randomly divided into control group [PBS, cells exposed to H2O2 (600 µmol/L) for 20 min to induce mitochondrial oxidant damage], resveratrol group (0.01, 0.1, 1, 5, 10 and 20 µmol/L for 20 min at 20 min before exposing to H2O2), resveratrol plus inhibitor group (1 µmol/L KT5823 for 10 min at 10 min before 5 µmol/L resveratrol treatment) and inhibitor group (1 µmol/L KT5823 for 10 min). Mitochondrial membrane potential (ΔΨm) was measured by staining cells with tetramethylrhodamine ethyl ester (TMRE) and the mitochondrial permeability transition pore (mPTP) opening was evaluated by measuring the decrease of TMRE fluorescence intensity. Immunofluorescence assay was used to observe GSK-3β phosphorylation. The phosphorylation of GSK-3β and VASP were determined by Western blot. To detect intracellular NO, cells were loaded with DAF-FM DA (specific fluorescent dye of NO) and imaged with confocal microscopy.</p><p><b>RESULTS</b>Compared to the control group, resveratrol (0.01-5 µmol/L) attenuated H2O2-induced mitochondrial damage reflected by attenuating the H2O2-induced TMRE fluorescence intensity decrease in a dose-dependent manner and the efficacy of 10 and 20 µmol/L resveratrol was significantly lower than that of 5 µmol/L resveratrol. Resveratrol also significantly upregulated the protein expression of VASP and increased GSK-3β Ser(9) phosphorylation, which could lead the inactivation of GSK-3β. These effects of resveratrol could be significantly abolished by protein kinase G inhibitor KT5823, while KT5823 alone did not affect GSK-3β and VASP phosphorylation. Confocal microscopy showed that DAF-FM (specific NO indicator) was similar between resveratrol and control group, suggesting that resveratrol did not produce NO.</p><p><b>CONCLUSIONS</b>Resveratrol could attenuate oxidant-induced mitochondrial damage in embryonic rat cardiomyocytes by inactivating GSK-3β via cGMP/PKG signaling pathway independent of NO-related mechanism.</p>