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Brazilian Journal of Medical and Biological Research, Volume: 53, Número: 6, Publicado: 2020
  • Animal models of human atherosclerosis: current progress Review

    Poznyak, A.V.; Silaeva, Y.Y.; Orekhov, A.N.; Deykin, A.V.

    Resumo em Inglês:

    Atherosclerosis retains the leading position among the causes of global morbidity and mortality worldwide, especially in the industrialized countries. Despite the continuing efforts to investigate disease pathogenesis and find the potential points of effective therapeutic intervention, our understanding of atherosclerosis mechanisms remains limited. This is partly due to the multifactorial nature of the disease pathogenesis, when several factors so different as altered lipid metabolism, increased oxidative stress, and chronic inflammation act together leading to the formation and progression of atherosclerotic plaques. Adequate animal models are currently indispensable for studying these processes and searching for novel therapies. Animal models based on rodents, such as mice and rats, and rabbits represent important tools for studying atherosclerosis. Currently, genetically modified animals allow for previously unknown possibilities in modelling the disease and its most relevant aspects. In this review, we describe the recent progress made in creating such models and discuss the most important findings obtained with them to date.
  • High levels of chemerin associated with variants in the NOS3 and APOB genes in rural populations of Ouro Preto, Minas Gerais, Brazil Research Article

    Batista, A.P.; Barbosa, K.F.; Masioli, C.Z.; Queiroz, E.M.; Marinho, C.C.; Cândido, A.P.C.; Machado-Coelho, G.L.L.

    Resumo em Inglês:

    Chemerin is an adipokine that has been associated with components of metabolic syndrome. It has been described to affect adipocyte metabolism and inflammatory responses in adipose tissue, as well as the systemic metabolism of lipids and glucose. Few epidemiological studies have evaluated classical and genetics cardiovascular risk factors (CVRFs) in the mixed adult rural population in Brazil. Therefore, the present study explored possible associations between CVRFs and chemerin. This cross-sectional study included 508 adults from the rural localities of Lavras Novas, Chapada, and Santo Antônio do Salto in Ouro Preto, Minas Gerais, Southeast Brazil. Demographic, behavioral, clinical, biochemical, anthropometric variables, and 12 single nucleotide polymorphisms (SNPs) linked with metabolic syndrome phenotypes were evaluated for associations with chemerin level. There was a significant association of high triglyceride levels [odds ratio (OR)=1.91, 95%CI: 1.23−2.98], insulin resistance (OR=1.82, 95%CI: 1.03−3.22), age (OR=1.64, 95%CI: 1.08−2.49), and sex (OR=1.99, 95%CI: 1.35−2.95) with high levels of chemerin. High chemerin levels were significantly associated with the genetic polymorphisms rs693 in the APOB gene (OR=1.50, 95%CI: 1.03−2.19) and rs1799983 in the NOS3 gene (OR=1.46, 95%CI: 1.01−2.12) for the AA and GT+TT genotypes, respectively. In the concomitant presence of genotypes AA of rs693 and GT+TT of rs1799983, the chance of presenting high levels of chemerin showed a 2.21-fold increase (95%CI: 1.25−3.88) compared to the reference genotype. The development of classical CVRFs in this population may be influenced by chemerin and by two risk genotypes characteristic of variants in well-studied genes for hypertension and dyslipidemia.
  • Aging and low-intensity exercise change oxidative biomarkers in brain regions and radiographic measures of femur of Wistar rats Research Article

    Silveira, E.M.S.; Santos, M.C.Q.; da Silva, T.C.B.; Silva, F.B.O.; Machado, C.V.; Elias, L.; Kolberg, A.; Kroth, A.; Partata, W.A.

    Resumo em Inglês:

    We investigated changes in oxidative biomarkers in brain regions such as brainstem, cerebellum, and cerebral cortex of 3-, 6-, 18-, 24-, and 30-month-old rats. We also assessed the effects of low-intensity exercise on these biomarkers in these regions of 6-, 18-, and 24-month-old rats that started exercise on a treadmill at 3, 15, and 21 months of age, respectively. Radiographic images of the femur were taken for all rats. A total of 25 rats (age: twelve 6-, ten 18-, ten 24-, and three 30-month-old rats) were used. Lipid hydroperoxide levels increased in cerebellum at 18 months. Total antioxidant activity exhibited lowest values in brainstem at 3 months. Superoxide dismutase activity did not exhibit significant changes during aging. Total thiol content exhibited lowest values in brain regions of 24- and 30-month-old rats. Exercise reduced total thiol content in brainstem at 6 months, but no change occurred in other regions and other ages. Femur increased its length and width and cortical thickness with advancing age. No change occurred in medullary width. Radiolucency increased and sclerosis was found in cortical and medullary bone with advancing age. Exercise reduced radiolucency and medullary sclerosis. Therefore, aging differentially changed oxidative biomarkers in different brain regions and radiographic measures of the femur. Low-intensity exercise only ameliorated some radiographic measurements of femur. Since the present study possessed limitations (small number of rats per group), a beneficial effect of regular low-intensity exercise on oxidative markers in brain cannot be ruled out.
  • A Brazilian regional basic diet-induced chronic malnutrition drives liver inflammation with higher ApoA-I activity in C57BL6J mice Research Article

    Santos, M.J.S.; Canuto, K.M.; de Aquino, C.C.; Martins, C.S.; Brito, G.A.C.; Pessoa, T.M.R.P.; Bertolini, L.R.; de Sá Carneiro, I.; Pinto, D.V.; Nascimento, J.C.R.; da Silva, B.B.; Valença Jr., J.T.; Guedes, M.I.F.; Owen, J.S.; Oriá, R.B.

    Resumo em Inglês:

    Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1β immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.
  • Treatment with β-elemene combined with paclitaxel inhibits growth, migration, and invasion and induces apoptosis of ovarian cancer cells by activation of STAT-NF-κB pathway Research Article

    Xiaomeng, Fu; Lei, Lv; Jinghong, An; Juan, Jiang; Qi, Yue; Dandan, Yuan

    Resumo em Inglês:

    In this study, we aimed to analyze the anti-cancer effects of β-elemene combined with paclitaxel for ovarian cancer. RT-qPCR, MTT assay, western blot, flow cytometry, and immunohistochemistry were used to analyze in vitro and in vivo anti-cancer effects of combined treatment of β-elemene and paclitaxel. The in vitro results showed that β-elemene+paclitaxel treatment markedly inhibited ovarian cancer cell growth, migration, and invasion compared to either paclitaxel or β-elemene treatment alone. Results demonstrated that β-elemene+paclitaxel induced apoptosis of SKOV3 cells, down-regulated anti-apoptotic Bcl-2 and Bcl-xl gene expression and up-regulated pro-apoptotic P53 and Apaf1 gene expression in SKOV3 cells. Administration of β-elemene+paclitaxel arrested SKOV3 cell cycle at S phase and down-regulated CDK1, cyclin-B1, and P27 gene expression and apoptotic-related resistant gene expression of MDR1, LRP, and TS in SKOV3 cells. In vivo experiments showed that treatment with β-elemene+paclitaxel significantly inhibited ovarian tumor growth and prolonged the overall survival of SKOV3-bearing mice. In addition, the treatment inhibited phosphorylated STAT3 and NF-κB expression in vitro and in vivo. Furthermore, it inhibited migration and invasion through down-regulation of the STAT-NF-κB signaling pathway in SKOV3 cells. In conclusion, the data suggested that β-elemene+paclitaxel can inhibit ovarian cancer growth via down-regulation of the STAT3-NF-κB signaling pathway, which may be a potential therapeutic strategy for ovarian cancer therapy.
  • Effect of ethanol extracts of Antrodia cinnamomea on head and neck squamous cell carcinoma cell line Research Article

    Liu, Li; Wang, Chen

    Resumo em Inglês:

    Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignant tumors. Ethanol extract of Antrodia cinnamomea (EEA) has been widely studied for its health benefits including anticancer effects. The purpose of this study was to assess the effects of EEA on HNSCC. Cell proliferation, transwell, and wound healing assays were performed. The impact of EEA on tumor growth was investigated using a xenograft model. Expressions of migration-related proteins (MMP-2, MMP-9, TIMP-1, and TIMP-2) and apoptosis-related proteins (cleaved caspase-9 and cleaved PARP) were determined using western blot analysis. The results indicated that EEA significantly inhibited the capacities of proliferation, invasion, and migration of HNSCC cells in a dose-dependent manner. Cleaved caspase-9 and cleaved PARP expressions were increased in cells treated with an increasing concentration of EEA, which suggested that EEA induced apoptosis of HNSCC. MMP-2 and MMP-9 were downregulated when cells were administered EEA, while TIMP-1 and TIMP-2 were not affected, which uncovered the mechanisms mediating the EEA-induced inhibition on cell invasion and migration. The animal experiment also suggested that EEA inhibited tumor growth. Our study confirmed the inhibitive effects of EEA on cell proliferation, invasion, and migration of HNSCC in vitro and in vivo, providing the basis for further study of the application of EEA as an effective candidate for cancer treatment.
  • Rhoifolin regulates oxidative stress and proinflammatory cytokine levels in Freund’s adjuvant-induced rheumatoid arthritis via inhibition of NF-κB Research Article

    Peng, Shanqin; Hu, Congqi; Liu, Xi; Lei, Lei; He, Guodong; Xiong, Chenming; Wu, Wenqian

    Resumo em Inglês:

    Rheumatoid arthritis (RA) is an autoimmune disease of knee joints involving pain and inflammation. Rhoifolin is a plant flavonoid known to have antioxidant and anti-inflammatory properties. This study was taken to identify the effect of rhoifolin on complete Freund’s adjuvant (CFA)-induced arthritis in the rat model. Treatment with rhoifolin (10 and 20 mg/kg) showed a significant improvement in the overall health parameters such as paw edema and weight loss. This improvement in morphological parameters corroborated the findings with gross morphological changes observed in the histopathological analysis. Rhoifolin treatment also caused a significant decrease in oxidative stress, evident from changes in intracellular levels of glutathione, glutathione peroxidase, malondialdehyde, and superoxide dismutase in the articular cartilage tissue. Moreover, proinflammatory cytokines, tumor necrosis factor (TNF)-α, interleukin(IL)-1β, and IL-6 showed a significant downregulation of gene expression and intracellular protein concentration levels. The NF-κB pathway showed a significant attenuation as evident in the significant reduction in the levels of NF-κB p65 and p-IκB-α. These results indicated that rhoifolin can be a natural therapeutic alternative to the extant regimens, which include non-steroidal anti-inflammatory drugs and immunosuppressants. Additionally, the antioxidant and anti-inflammatory action of rhoifolin was probably mediated by the NF-κB pathway. However, the exact target molecules of this pathway need to be determined in further studies.
  • Notoginsenoside R1 upregulates miR-221-3p expression to alleviate ox-LDL-induced apoptosis, inflammation, and oxidative stress by inhibiting the TLR4/NF-κB pathway in HUVECs Research Article

    Zhu, Lingbo; Gong, Xinyan; Gong, Jianping; Xuan, Yungang; Fu, Ting; Ni, Shimao; Xu, Lei; Ji, Ningning

    Resumo em Inglês:

    Atherosclerosis (AS) is a common vascular disease, which can cause apoptosis of vascular endothelial cells. Notoginsenoside R1 (NGR1) is considered an anti-AS drug. MicroRNAs (miRNAs) are believed to play a vital role in cell apoptosis and angiogenesis. This study aimed to explore the mechanism of NGR1 for treating AS through miRNAs. Flow cytometry was used to detect the apoptosis rate. The levels of inflammatory cytokines interleukin (IL)-6 and IL-1β were detected using ELISA. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels were measured using corresponding assay kits. Quantitative real-time polymerase chain reaction (qRT-PCR) assay was performed to detect miR-221-3p expression. Dual-luciferase reporter and RNA immunoprecipitation assays were carried out to examine the relationship between miR-221-3p and toll-like receptors 4 (TLR4). Also, western blot analysis was performed to determine the levels of TLR4 and nuclear factor kappa B (NF-κB) signaling pathway-related proteins. Oxidized low-density lipoprotein (ox-LDL) induced human umbilical vein endothelial cells (HUVECs) apoptosis, inflammation, and oxidative stress. NGR1 alleviated the negative effect of ox-LDL through promoting the expression of miR-221-3p in HUVECs. TLR4 was a target of miR-221-3p, and its overexpression could reverse the inhibition effects of miR-221-3p on apoptosis, inflammation, and oxidative stress. NGR1 improved miR-221-3p expression to inhibit the activation of the TLR4/NF-κB pathway in ox-LDL-treated HUVECs. NGR1 decreased ox-LDL-induced HUVECs apoptosis, inflammation, and oxidative stress through increasing miR-221-3p expression, thereby inhibiting the activation of the TLR4/NF-κB pathway. This study of the mechanism of NGR1 provided a more theoretical basis for the treatment of AS.
  • Evaluation of factors for predicting risk of uveitis recurrence in Behcet's disease patients Research Article

    Cai, Jianfei; Qi, Lin; Chen, Yong; Zou, Jun; Shen, Yan; Luo, Dan; Bao, Huafang; Ye, Jingfen; Ma, Haifen; Guan, Jian-Long

    Resumo em Inglês:

    This study aimed to investigate the predictive factors for uveitis recurrence (UR) risk in Behcet's disease (BD) patients. BD patients (n=164) with a history of uveitis were recruited, and demographic data, clinical features, and laboratory tests were recorded. Uveitis was defined as anterior uveitis, intermediate uveitis, posterior uveitis, panuveitis referring to the “International Uveitis Study Group recommendations for the evaluation of intraocular inflammatory disease”. In total, there were 70 UR patients and 94 non-UR patients. Compared to non-UR patients, UR patients appeared to be older and presented with increased uveitis occurrence rate and times within 3 months, oral ulcers occurrence rate, as well as higher concentrations of triglycerides (TG), total cholesterol (TC), low-density lipoprotein (LDL), and serum amyloid A (SAA). Multivariate logistic model disclosed that uveitis occurrence times within 3 months, oral ulcers, TG, LDL, and SAA independently predicted higher risk of UR. Furthermore, receiver operating characteristic curve analysis showed that the combination of uveitis occurrence times within 3 months, oral ulcers, TG, LDL, and SAA exhibited a high predictive value for UR risk with an area under the curve of 0.983 (95%CI: 0.969−0.998). In conclusion, uveitis occurrence times within 3 months, oral ulcers, TG, LDL, and SAA might be potential predictive factors for UR risk in BD patients, which can help in prevention and management of the disease.
  • Voxel-wise meta-analysis of structural changes in gray matter of Parkinson’s disease patients with mild cognitive impairment Research Article

    Qin, B.; Yang, M.X.; Gao, W.; Zhang, J.D.; Zhao, L.B.; Qin, H.X.; Chen, H.

    Resumo em Inglês:

    Evidence from previous voxel-based morphometry (VBM) studies indicates that widespread brain regions are involved in Parkinson’s disease with mild cognitive impairment (PD-MCI). However, the spatial localization reported for gray matter (GM) abnormalities is heterogeneous. The aim of the present study was to quantitatively integrate studies on GM abnormalities observed in PD-MCI in order to determine whether a pattern exists. Eligible whole-brain VBM studies were identified by a systematic search of articles in PubMed and EMBASE databases spanning from 1995 to January 1, 2019. A meta-analysis was performed to investigate regional GM abnormalities in PD-MCI. The anisotropic effect size version of seed-based d mapping (AES-SDM) meta-analysis was conducted to explore the GMV differences of PD-MCI compared with PD patients with normal cognitive function (PD-NC). A total of 12 studies comprising 243 PD-MCI patients and 326 PD-NC were included in the meta-analysis. PD-MCI patients showed a robust GM decrease in the left insula and left superior temporal gyrus. Moreover, meta-regression analysis demonstrated that age, PD duration and stage, and Unified Parkinson’s Disease Rating Scale III and Mini-Mental State Examination scores might be partly correlated with the GM abnormalities observed in PD-MCI patients. The convergent findings of this quantitative meta-analysis revealed a characteristic neuroanatomical pattern in PD-MCI. The findings provide some evidence that MCI in PD may result in the breakdown of the insula and temporal gyrus, which may serve as specific regions of interest for further investigations.
  • Correlation between amyloid deposits affecting renal compartments and glomerular filtration rate during renal biopsy in a renal amyloidosis case series Research Article

    Fonseca, E.O.; Caldas, M.L.R.; Soares Filho, P.J.; Almeida, J.R.

    Resumo em Inglês:

    Amyloidosis comprises a group of disorders that accumulate modified autologous proteins in organs, mainly the kidneys. Few studies have addressed the amyloid compartmental distribution and associated clinical outcomes. The aim of this study was to present a case series of renal amyloidosis correlating histopathological data with glomerular filtration rate (GFR) during kidney biopsy. We studied 53 cases reviewed by nephropathologists from 2000 to 2018 in a single kidney biopsy center in Brazil. GFR was estimated using the CKD-EPI formula. Cases were divided into Group A ≥60 and Group B <60 mL·min−1·(1.73 m2)−1 using the estimated GFR during kidney biopsy. Semiquantitative histopathological study was performed, including extension and distribution of amyloid deposits by compartments (glomeruli, tubulointerstitial tissue, and vessels). Statistical analyses were made to understand associations with lower GFR. No difference was seen for age, gender, proteinuria, hematuria, subtype of amyloid protein, arteriosclerosis, interstitial fibrosis/infiltrate, or glomerular and interstitial amyloid deposits. After a previous P value <0.1 in the descriptive analysis, the following variables were selected: globally sclerotic glomeruli, high blood pressure, and the extension of vascular amyloid deposition. A binary logistic regression model with GFR as the dependent variable showed history of hypertension and vascular amyloid to be robust and independent predictors of Group B <60 mL·min−1·(1.73 m2)−1. Beyond the histopathologic diagnosis of amyloidosis, a semiquantitative approach on renal biopsy could provide new insights. Vascular amyloid is an independent predictor of renal dysfunction in cases of renal amyloidosis.
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