Resumo em Inglês:

Muscular atrophy is a progressive degeneration characterized by muscular proteolysis, loss of mass and decrease in fiber area. Tendon rupture induces muscular atrophy due to an intrinsic functional connection. Local inhibition of nitric oxide synthase (NOS) by Nω-nitro-L-arginine methyl ester (L-NAME) accelerates tendon histological recovery and induces functional improvement. Here we evaluate the effects of such local nitrergic inhibition on the pattern of soleus muscle regeneration after tenotomy. Adult male Wistar rats (240 to 280 g) were divided into four experimental groups: control (n=4), tenotomized (n=6), vehicle (n=6), and L-NAME (n=6). Muscular atrophy was induced by calcaneal tendon rupture in rats. Changes in muscle wet weight and total protein levels were determined by the Bradford method, and muscle fiber area and central core lesion (CCL) occurrence were evaluated by histochemical assays. Compared to tenotomized (69.3±22%) and vehicle groups (68.1%±17%), L-NAME treatment induced an increase in total protein level (108.3±21%) after 21 days post-injury. A reduction in fiber areas was observed in tenotomized (56.3±1.3%) and vehicle groups (53.9±3.9%). However, L-NAME treatment caused an increase in this parameter (69.3±1.6%). Such events were preceded by a remarkable reduction in the number of fibers with CCL in L-NAME-treated animals (12±2%), but not in tenotomized (21±2.5%) and vehicle groups (19.6±2.8%). Altogether, our data reveal that inhibition of tendon NOS contributed to the attenuation of atrophy and acceleration of muscle regeneration.

Resumo em Inglês:

This study aimed to explore the roles of monocyte chemotactic protein 1 (MCP-1) and nuclear factor kappa B (NF-κB) in immune response to spinal tuberculosis in a New Zealand white rabbit model. Forty-eight New Zealand white rabbits were collected and divided into four groups: experimental group (n=30, spinal tuberculosis model was established), the sham group (n=15, sham operation was performed) and the blank group (n=3). The qRT-PCR assay and western blotting were applied to detect the mRNA and protein expressions of MCP-1 and NF-κB in peripheral blood. ELISA was used to measure serum levels of MCP-1, NF-κB, IFN-γ, IL-2, IL-4, and IL-10. Flow cytometry was adopted to assess the distributions of CD4+, CD8+ lymphocytes and CD4+ CD25+ Foxp3 lymphocyte subsets. Compared with the sham and blank groups, the mRNA and protein expressions of MCP-1 and NF-κB in the experimental group were significantly increased. The experimental group had lower serum levels of IL-2 and IFN-γ and higher serum level of IL-10 than the sham and blank groups. In comparison to the sham and blank groups, CD4+ T lymphocyte subsets percentage, CD4+/CD8+ ratio and CD4+ CD25+ Foxp3+ Tregs subsets accounting for CD4+ lymphocyte in the experimental group were lower, while percentage of CD8+ T lymphocyte subsets was higher. Our study provided evidence that higher expression of MCP-1 and NF-κB may be associated with decreased immune function of spinal tuberculosis, which can provide a new treatment direction for spinal tuberculosis.

Resumo em Inglês:

Ovarian cancer is one of the most common malignancies in women. Semaphorin 4D (sema 4D) is involved in the progress of multiple cancers. In the presence of estrogen-like ligands, estrogen receptors (ERα and ERβ) participate in the progress of breast and ovarian cancers by transcriptional regulation. The aim of the study was to investigate the role of sema 4D and elucidate the regulatory pattern of ERα and ERβ on sema 4D expression in ovarian cancers. Sema 4D levels were up-regulated in ovarian cancer SKOV-3 cells. Patients with malignant ovarian cancers had significantly higher sema 4D levels than controls, suggesting an oncogene role of sema 4D in ovarian cancer. ERα expressions were up-regulated in SKOV-3 cells compared with normal ovarian IOSE80 epithelial cells. Conversely, down-regulation of ERβ was observed in SKOV-3 cells. Forced over-expression of ERα and ERβ in SKOV-3 cells was manipulated to establish ERα+ and ERβ+ SKOV-3 cell lines. Incubation of ERα+ SKOV-3 cells with ERs agonist 17β-estradiol (E2) significantly enhanced sema 4D expression and rate of cell proliferation. Incubated with E2, ERβ+ SKOV-3 cells showed lower sema 4D expression and cell proliferation. Blocking ERα and ERβ activities with ICI182-780 inhibitor, sema 4D expressions and cell proliferation of ERα+ and ERβ+ SKOV-3 cells were recovered to control levels. Taken together, the data showed that sema 4D expression was positively correlated with the progress of ovarian cancer. ERα positively regulated sema 4D expression and accelerated cell proliferation. ERβ negatively regulated sema 4D expression and inhibited cell multiplication.

Resumo em Inglês:

Several long non-coding RNA (lncRNA) might be correlated with the prognosis of colorectal cancer (CRC) and serve as a diagnostic and prognostic biomarker. However, the exact expression pattern of small nucleolar RNA host gene 12 (SNHG12) in colorectal cancer and its clinical significance remains unclear. The level of SNHG12 was detected by qRT-PCR in CRC tissues and CRC cells. MTT assay and colony formation assay were performed to examine the cell proliferation of CRC cells transfected with pcDNA-SNHG12 or si-SNHG12. Flow cytometry technology was used to detect cell cycle and cell apoptosis of CRC cells transfected with pcDNA-SNHG12 or si-SNHG12. The protein level of cell cycle progression-related molecules, including cyclin-dependent kinases (CDK4, CDK6), cyclin D1 (CCND1) and cell apoptosis-related molecule caspase 3 was detected by western blot. The effect of SNHG12 knockdown was examined in vivo. Increased levels of SNHG12 were observed in CRC tissues and in CRC cells. SNHG12 promoted the cell proliferation of CRC cells. In addition, SNHG12 overexpression boosted the cell cycle progression of SW480 cells transfected with pcDNA-SNHG12 and SNHG12 knockdown inhibited the cell cycle progression of HT29 cells transfected with si-SNHG12. SNHG12 also inhibited the cell apoptosis of CRC cells. We also found that SNHG12 increased the expression of cell cycle-related proteins and suppressed the expression of caspase 3. Our results suggest that SNHG12 promoted cell growth and inhibited cell apoptosis in CRC cells, indicating that SNHG12 might be a useful biomarker for colorectal cancer.

Resumo em Inglês:

Diabetic retinopathy (DR) is one of the common and specific microvascular complications of diabetes. This study aimed to investigate the anti-angiogenic effect of kaempferol and explore its underlying molecular mechanisms. The mRNA expression level of vascular endothelial growth factor (VEGF) and placenta growth factor (PGF) and the concentrations of secreted VEGF and PGF were measured by qTR-PCR and ELISA assay, respectively. Human retinal endothelial cells (HRECs) proliferation, migration, and sprouting were measured by CCK-8 and transwell, scratching wound, and tube formation assays, respectively. Protein levels were determined by western blot. High glucose (25 mM) increased the mRNA expression levels of VEGF and PGF as well as the concentrations of secreted VEGF and PGF in HRECs, which can be antagonized by kaempferol (25 µM). Kaempferol (5-25 µM) significantly suppressed cell proliferation, migration, migration distance and sprouting of HRECs under high glucose condition. The anti-angiogenic effect of kaempferol was mediated via downregulating the expression of PI3K and inhibiting the activation of Erk1/2, Src, and Akt1. This study indicates that kaempferol suppressed angiogenesis of HRECs via targeting VEGF and PGF to inhibit the activation of Src-Akt1-Erk1/2 signaling pathway. The results suggest that kaempferol may be a potential drug for better management of DR.

Resumo em Inglês:

We aimed to investigate the influence of regulatory T cells including CD4+CD25+, CD8+CD28- and hepatitis B virus (HBV) genotype on sustained virological response and tolerance of nucleoside drugs. One hundred and thirty-seven patients were enrolled. Lamivudine was administered to 84 patients. Entecavir was administered to the other 53 patients. Before treatment, biochemical tests, HBV DNA load, HBV serum level, HBV genotype, PB CD3+, CD4+, CD8+, CD4+CD25+/CD3+, and CD8+CD28-/CD3+ frequencies were measured. Based on HBV DNA loads after 4 weeks of therapy, patients were divided into response group and suboptimal response group. The lamivudine group received treatment continuously, and then patients were categorized into non-resistance group and resistance group. Compared with the suboptimal response and resistance groups for lamivudine, CD4+CD25+/CD3+ levels were higher in the response and non-resistance groups (t=4.372, P=0.046; t=7.262, P=0.017). In the non-resistance group, CD8+CD28-/CD3+ frequency was lower than in the resistance group (t=5.527, P=0.037). Virus load and hepatitis B E antigen (HBeAg)-positive rate were significantly lower than in the response and resistance group (t=2.164, P=0.038; X2=4.239, P=0.040; t=2.015, P=0.044; X2=16.2, P=0.000). Incidence of drug resistance was high in patients with virogene type C. For the virological response to entecavir, CD8+CD28-/CD3+ level was significantly lower than that of the suboptimal response group (t=6.283, P=0.036). Response and suboptimal response groups were compared in CD3+, CD4+, CD8+, CD4+CD25+/CD3+ and virus genotype, and differences were not statistically significant (P>0.05). Baseline regulatory T cells including CD4+CD25+/CD3+ and CD8+CD28-/CD3+ frequencies have a relationship with the incidence of rapid virological response and the resistance to nucleoside drugs. Patients with HBV genotype C receiving lamivudine more often underwent drug resistance. Antiviral efficacy and the resistance to lamivudine were closely correlated with baseline factors; the same cannot be found for entecavir.

Resumo em Inglês:

This study presents the characterization of an X-ray irradiator through dosimetric tests, which confirms the actual dose rate that small animals and cells will be exposed to during radiobiological experiments. We evaluated the linearity, consistency, repeatability, and dose distribution in the positions in which the animals or cells are placed during irradiation. In addition, we evaluated the performance of the X-ray tube (voltage and tube operating current), the radiometric survey (leakage radiation) and safety devices. The irradiator default setting was established as 160 kV and 25 mA. Tests showed that the dose rate was linear overtime (R2=1) and remained stable for long (constant) and short (repeatability) intervals between readings. The mean dose rate inside the animal cages was 1.27±0.06 Gy/min with a uniform beam of 95.40% (above the minimum threshold guaranteed by the manufacturer). The mean dose rate inside the cell plates was 0.92±0.19 Gy/min. The dose rate dependence with tube voltage and current presented a quadratic and linear relationship, respectively. There was no observed mechanical failure during evaluation of the irradiator safety devices and the radiometric survey obtained a maximum ambient equivalent dose rate of 0.26 mSv/h, which exempts it from the radiological protection requirements of the International Atomic Energy Agency. The irradiator characterization enables us to perform radiobiological experiments, and assists or even replaces traditional therapy equipment (e.g., linear accelerators) for cells and small animal irradiation, especially in early research stages.

Resumo em Inglês:

Functional food intake has been highlighted as a strategy for the prevention of cardiovascular diseases by reducing risk factors. In this study, we compared the effects of oral treatment with soy milk and simvastatin on dyslipidemia, left ventricle remodeling and atherosclerotic lesion of LDL receptor knockout mice (LDLr-/-) fed a hyperlipidic diet. Forty 3-month old male LDLr-/- mice were distributed into four groups: control group (C), in which animals received standard diet; HL group, in which animals were fed a hyperlipidic diet; HL+SM or HL+S groups, in which animals were submitted to a hyperlipidic diet plus soy milk or simvastatin, respectively. After 60 days, both soy milk and simvastatin treatment prevented dyslipidemia, atherosclerotic lesion progression and left ventricle hypertrophy in LDLr-/- mice. These beneficial effects of soy milk and simvastatin were associated with reduced oxidative stress and inflammatory state in the heart and aorta caused by the hyperlipidic diet. Treatment with soy milk was more effective in preventing HDLc reduction and triacylglycerol and VLDLc increase. On the other hand, simvastatin was more effective in preventing an increase in total cholesterol, LDLc and superoxide production in aorta, as well as CD40L both in aorta and left ventricle of LDLr-/-. In conclusion, our results suggest a cardioprotective effect of soy milk in LDLr-/- mice comparable to the well-known effects of simvastatin.

Resumo em Inglês:

The objective of this study was to evaluate lung protection by the volatile anesthetic sevoflurane (SEVO), which inhibits apoptosis. Male Sprague-Dawley rats (250–280 g; n=18) were randomly divided into three groups. The LPS group received 5 mg/kg endotoxin (lipopolysaccharide), which induced acute lung injury (ALI). The control (CTRL) group received normal saline and the SEVO group received sevoflurane (2.5%) for 30 min after ALI was induced by 5 mg/kg LPS. Samples were collected for analysis 12 h after LPS. Lung injury was assessed by pathological observations and tissue wet to dry weight (W/D) ratios. Apoptotic index (AI) was determined by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay and electron microscopy. Caspase-3 and cleaved-caspase-3 protein levels were determined by immunocytochemistry and western blotting, respectively. Bcl-xl levels were measured by western blotting and Bcl-2 levels by quantitative real-time polymerase chain reaction and western blotting. In the LPS group, W/D ratios, AI values, caspase-3 and cleaved-caspase-3 levels were significantly higher than in the CTRL group and lung injury was more severe. In the SEVO group, W/D ratios, AI, caspase-3 and cleaved-caspase-3 were lower than in the LPS group. Bcl-2 and Bcl-xl expression were higher than in the LPS group and lung injury was attenuated. Sevoflurane inhalation protected the lungs from injury by regulating caspase-3 activation and Bcl-xl and Bcl-2 expression to inhibit excessive cell apoptosis, and such apoptosis might be important in the pathogenesis of LPS-induced ALI.

Resumo em Inglês:

The aim of the present study was to provide new spirometry reference equations in a sample of the Brazilian population for the following parameters: forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FVC ratio, peak of expiratory flow (PEF), forced expiratory flow at 50% (FEF50%), 75% average vital capacity (FEF25-75%), and average forced expiratory flow time (FEFT). This was a prospective study using results from chest radiographs, electrocardiograms, and questionnaires to investigate the participants' respiratory symptoms, sedentarism, and comorbidities (Charlson comorbidity index). From December 2010 to July 2014, individuals were randomly selected from various locations in the state of Rio de Janeiro. All individuals were examined by a single technician in the morning at the laboratory, and performed the spirometry with the same spirometer. Spirometry values were tabulated for the creation of three equation models: linear regression, logarithmic regression, and logarithms through a method that incorporates the lambda, median, and coefficient of variation (LMS method). Initially, 7003 individuals from both genders were contacted, and 454 were recruited. The data from the new equations were compared with one Brazilian and eight international equations, resulting in a high correlation (r>0.9). The values derived from the LMS method and linear regression were very similar (P>0.5), and both could be used to acquire the reference values for Brazilian spirometry. Data derived from the equations of this study were different from the current Brazilian equation, which could be justified by the different method used.

Resumo em Inglês:

The aim of this study was to analyze if off-pump coronary artery bypass surgery (CABG) is associated with better treatment outcomes in elderly patients (>70 years of age) than on-pump CABG, using meta-analysis. Medline, PubMed, Cochrane and Google Scholar databases were searched until September 13, 2016. Sensitivity and quality assessment were performed. Twenty-two studies, three randomized control trials (RCTs) and 20 non-RCTs were included with 24,127 patients. The risk of death associated with on-pump or off-pump CABG in the RCTs were similar (pooled OR=0.945, 95%CI=0.652 to 1.371, P=0.766). However, in the non-RCTs, mortality risk was lower in patients treated with off-pump CABG than on-pump CABG (pooled OR=0.631, 95%CI=0.587 to 0.944, P=0.003). No differences were observed between the two treatment groups in terms of the occurrence of 30-day post-operative stroke or myocardial infarction (P≥0.147). In the non-RCTs, off-pump CABG treatment was associated with a shorter length of hospital stay (pooled standardized difference in means=-0.401, 95%CI=-0.621 to -0.181, P≤0.001). The meta-analysis with pooled data from non-RCTs, but not RCTs, found that mortality was lower with off-pump compared with on-pump CABG, and suggested that there may be some benefit of off-pump CABG compared with on-pump CABG in the risk of mortality and length of hospital stay.

Resumo em Inglês:

The aim of this study was to investigate the effect of Roux-en-Y gastric bypass (RYGB) on the peripheral blood microRNAs (miRNAs) of patients with type 2 diabetes mellitus (T2DM). miRNAs are small 20- to 22-nucleotide (nt) noncoding RNAs. They constitute a novel class of gene regulators that negatively regulate gene expression at the post-transcriptional level. miRNAs play an important role in several biological processes. Twelve patients with T2DM who were scheduled to undergo laparoscopic RYGB surgery were separated into two groups, using a body mass index of 30 kg/m2 as a cut-off point. Venous blood was collected before operation and 12 months after operation. A significant change was observed in the peripheral blood miRNA expression profile of both groups after RYGB surgery compared with those before operation. The expression levels of hsa-miR-29a-3p, hsa-miR-122-5p, hsa-miR-124-3p, and hsa-miR-320a were downregulated. The methylation state of the CpG sites within an approximately 400-bp genomic DNA fragment of each of the four miRNA genes, including about 200 bp upstream and 100 bp downstream of the pre-miRNA, did not vary after RYGB surgery. With remission of T2DM in both groups, RYGB could modulate the expression level of many peripheral blood miRNAs associated with lipid metabolism, insulin secretion, beta-cell function, and insulin resistance. The expression level of peripheral blood diabetes-related miRNA varied in patients with T2DM after receiving RYGB surgery, laying a strong foundation for future studies on this subject. The molecular mechanisms underlying RYGB surgery that can cause aberrant expression of miRNA remains to be determined.