Scielo RSS <![CDATA[Brazilian Journal of Medical and Biological Research]]> vol. 51 num. 8 lang. en <![CDATA[SciELO Logo]]> <![CDATA[Role of non-coding RNAs in non-aging-related neurological disorders]]> Protein coding sequences represent only 2% of the human genome. Recent advances have demonstrated that a significant portion of the genome is actively transcribed as non-coding RNA molecules. These non-coding RNAs are emerging as key players in the regulation of biological processes, and act as "fine-tuners" of gene expression. Neurological disorders are caused by a wide range of genetic mutations, epigenetic and environmental factors, and the exact pathophysiology of many of these conditions is still unknown. It is currently recognized that dysregulations in the expression of non-coding RNAs are present in many neurological disorders and may be relevant in the mechanisms leading to disease. In addition, circulating non-coding RNAs are emerging as potential biomarkers with great potential impact in clinical practice. In this review, we discuss mainly the role of microRNAs and long non-coding RNAs in several neurological disorders, such as epilepsy, Huntington disease, fragile X-associated ataxia, spinocerebellar ataxias, amyotrophic lateral sclerosis (ALS), and pain. In addition, we give information about the conditions where microRNAs have demonstrated to be potential biomarkers such as in epilepsy, pain, and ALS. <![CDATA[Strontium ranelate as a possible disease-modifying osteoarthritis drug: a systematic review]]> Considering that osteoarthritis (OA) is the most prevalent joint disease worldwide, multiple pharmacological treatments have been proposed to alter the articular structure with potential benefit in the progression of the disease. The so-called disease-modifying OA drugs have been frequently investigated but conclusive findings are rare. Strontium ranelate (SrRan) is a drug usually prescribed to treat osteoporosis, with proven effects in decreasing the risk of fractures and possible effect in reducing the progression of OA. The objective of this review was to demonstrate the current panorama of knowledge on the use of SrRan in clinical and experimental models, clarifying its mechanisms of action and describing possible anti-nociceptive and anti-inflammatory effects. The systematic review was based on the PRISMA statement and included articles that are indexed in scientific databases. Fifteen studies were included: seven pre-clinical and eight clinical studies. Despite the limited number of studies, the results suggest a positive effect of SrRan in patients with OA, through changes in functional capacity and reduction of progression of morphological parameters and joint degradation, with moderate quality of evidence for those clinical outcomes. Novel studies are necessary to elucidate the molecular targets of SrRan, focusing on anti-inflammatory effects and histological changes promoted by SrRan, which seemed to reduce the progression of OA in the experimental and clinical studies. <![CDATA[Apolipoprotein B and angiotensin-converting enzyme polymorphisms and aerobic interval training: randomized controlled trial in coronary artery disease patients]]> Physical training has been strongly recommended as a non-pharmacological treatment for coronary artery disease (CAD). Genetic polymorphisms have been studied to understand the biological variability in response to exercise among individuals. This study aimed to verify the possible influence of apolipoprotein B (ApoB: rs1042031 and rs693) and angiotensin-converting enzyme (ACE-ID: rs1799752) genotypes on the lipid profile and functional aerobic capacity, respectively, after an aerobic interval training (AIT) program in patients with CAD and/or cardiovascular risk factors. Sixty-six men were randomized and assigned to trained group (n=32) or control group (n=34). Cardiopulmonary exercise test was performed to determine the ventilatory anaerobic threshold (VAT) from cardiorespiratory variables. The AIT program, at an intensity equivalent to %VAT (70–110%), was conducted three times a week for 16 weeks. ApoB gene polymorphisms (−12669C&gt;T (rs1042031) and −7673G&gt;A (rs693)) were identified by real-time polymerase chain reaction (PCR). I/D polymorphism in the ACE gene (rs1799752) was identified through PCR and fragment size analysis. After 16 weeks, low-density lipoprotein (LDL) levels increased in the trained and control groups with the GA+AA genotype (−7673G&gt;A) of the ApoB gene. Trained groups with ACE-II and ACE-ID genotypes presented an increase in oxygen consumption (VO2VAT) and power output after the AIT program. The presence of the ACE I-allele was associated with increased aerobic functional capacity after the AIT program. Increased LDL levels were observed over time in patients with the −7673G&gt;A polymorphism of the ApoB gene. Trial Registration Information: NCT02313831 <![CDATA[Anethole reduces oxidative stress and improves <em>in vitro</em> survival and activation of primordial follicles]]> Primordial follicles, the main source of oocytes in the ovary, are essential for the maintenance of fertility throughout the reproductive lifespan. To the best of our knowledge, there are no reports describing the effect of anethole on this important ovarian follicle population. The aim of the study was to investigate the effect of different anethole concentrations on the in vitro culture of caprine preantral follicles enclosed in ovarian tissue. Randomized ovarian fragments were fixed immediately (non-cultured treatment) or distributed into five treatments: α-MEM+ (cultured control), α-MEM+ supplemented with ascorbic acid at 50 μg/mL (AA), and anethole at 30 (AN30), 300 (AN300), or 2000 µg/mL (AN2000), for 1 or 7 days. After 7 days of culture, a significantly higher percentage of morphologically normal follicles was observed when anethole at 2000 μg/mL was used. For both culture times, a greater percentage of growing follicles was observed with the AN30 treatment compared to AA and AN2000 treatments. Anethole at 30 and 2000 µg/mL concentrations at days 1 and 7 of culture resulted in significantly larger follicular diameter than in the cultured control treatment. Anethole at 30 µg/mL concentration at day 7 showed significantly greater oocyte diameter than the other treatments, except when compared to the AN2000 treatment. At day 7 of culture, levels of reactive oxygen species (ROS) were significantly lower in the AN30 treatment than the other treatments. In conclusion, supplementation of culture medium with anethole improves survival and early follicle development at different concentrations in the caprine species. <![CDATA[Detection of sputum cofilin-1 as indicator of malignancy]]> Cofilin-1 (CFL1), a small protein of 18 kDa, has been studied as a biomarker due to its involvement in tumor cell migration and invasion. Our aim was to evaluate CFL1 as an indicator of malignancy and aggressiveness in sputum samples. CFL1 was analyzed by ELISA immunoassay in the sputum of 73 lung cancer patients, 13 cancer-free patients, and 6 healthy volunteers. Statistical analyses included ANOVA, ROC curves, Spearman correlation, and logistic regression. Sputum CFL1 levels were increased in cancer patients compared to cancer-free patients and volunteers (P&lt;0.05). High expression of sputum CFL1 was correlated to T4 stage (P=0.01) and N stage (P=0.03), tobacco history (P=0.01), and squamous cell carcinoma histologic type (P=0.04). The accuracy of sputum CFL1 in discriminating cancer patients from cancer-free patients and healthy volunteers were 0.78 and 0.69, respectively. CFL1 at a cut-off value of 415.25 pg/mL showed sensitivity/specificity of 0.80/0.70 in differentiating between healthy volunteers and cancer patients. Sputum CFL1 was also able to identify cancer-free patients from patients with lung cancer. The AUC was 0.70 and, at a cut-off point ≥662.63 pg/mL, we obtained 60% sensitivity and 54% specificity. Logistic regression analysis controlled for tobacco history, histologic types, and N stage showed that cancer cell-associated CFL1 was an independent predictor of death. Smoker patients with squamous cell carcinoma, lymph node metastasis and sputum CFL1&gt;1.475 pg/mL showed augmented chance of death, suggesting lung cancer aggressiveness. CFL1 presented diagnostic value in detecting lung cancer and was associated to tumor aggressiveness. <![CDATA[Association between tumor necrosis factor alpha rs1800629 polymorphism and risk of osteoarthritis in a Chinese population]]> Osteoarthritis (OA) is the most common degenerative disease affecting articular cartilage. Some studies indicate that tumor necrosis factor alpha (TNF-α) gene rs1800629 polymorphism was associated with OA risk among Caucasian populations. To examine the role of this candidate gene in Asian populations, we conducted a hospital-based case-control study involving 257 knee OA patients and 305 controls in a Chinese population. Genotyping was performed using a custom-by-design 48-Plex single nucleotide polymorphism (SNP) Scan™ kit. Our study indicated that the AA genotype of TNF-α rs1800629 polymorphism was associated with increased risk of OA. Subsequently, we conducted a meta-analysis and found that rs1800629 polymorphism increased the risk of OA in the recessive and homozygous models. Stratification analysis of ethnicity also obtained a significant association among Asian populations. In conclusion, TNF-α rs1800629 polymorphism confers susceptibility to OA, especially among Asians. Larger studies with more diverse ethnic populations are needed to confirm these results. <![CDATA[PD-1/PD-L1 regulates Treg differentiation in pregnancy-induced hypertension]]> Pregnancy-induced hypertension (PIH) causes significant maternal and fetal morbidity and mortality. A decreased number of regulatory T (Treg) cells is associated with the pathogenesis of PIH. The programmed cell death-1 (PD-1)/PD-ligand 1 (PD-L1) pathway is critical to normal pregnancy (NP) by promoting Treg cell development. However, the relationship between PD-1/PD-L1 and Treg differentiation in PIH has not been fully elucidated. In this study, venous blood was obtained from 20 NP and 58 PIH patients. Peripheral blood mononuclear cells (PBMCs) were isolated from venous blood. The levels of Treg-related cytokines (TGF-β, IL-10, and IL-35) in serum and PBMCs were measured by ELISA. The percentage of Treg cells in PBMCs was assessed by flow cytometry. The mRNA levels of Treg-specific transcription factor Foxp3 in PBMCs, and PD-1 and PD-L1 in Treg cells were detected by qRT-PCR. The protein levels of PD-1 and PD-L1 in Treg cells were evaluated by western blot. The serum levels of TGF-β, IL-10, IL-35, and Foxp3 mRNA expression and CD4+CD25+ Treg cell percentage in PBMCs were decreased in PIH. Furthermore, a significant increase of PD-1 in Treg cells was found in PIH compared with NP. In addition, PD-L1 Fc, an activator of PD-1/PD-L1 pathway, increased Treg cell percentage, enhanced Foxp3 mRNA expression, and elevated levels of TGF-β, IL-10, and IL-35 in PBMCs. However, anti-PD-L1 mAb exerted a reverse effect. These findings revealed that PD-L1 Fc had a favorable effect on Treg cell differentiation, indicating a potential therapeutic value of PD-1/PD-L1 pathway for PIH treatment. <![CDATA[Low prevalence of relevant findings in inappropriate echocardiograms and discordant perceptions between cardiologists and patients]]> Complementary examinations are “inadequate” whenever the likelihood of benefits from their indication is lower than the negative results. The low benefit is a result of poor performance in detecting relevant changes that lead to improved behavior. However, inadequate examinations are prevalent and little is known about patients' notions of the usefulness of such indications. The aim of this study was to describe relevant findings in inappropriate echocardiograms and to assess the level of agreement between patients and cardiologists regarding their usefulness. Adults without known cardiovascular disease who were referred for echocardiogram by inappropriate criteria according to the American College of Cardiology were selected. Relevant findings were defined by any change in the degree of moderate to severe, according to the American Society of Echocardiography. We tested the level of agreement between the patients who underwent echocardiographic examination and the physicians who requested the exam through a standard questionnaire. Five hundred patients were included, with average age of 52±17 years (47% males). Only 17 patients had any relevant changes (3.4%, 95%CI=2 to 5.4%). The most frequent alterations included valve changes in 8 and diastolic dysfunction grade II in 6 patients. Eighty-seven examinations were performed to determine the level of agreement between patients and cardiologists. For the question “Is this test really necessary?”, 92% of patients responded positively, compared with 5% of cardiologists (Kappa negative 0.04; P=0.01). The frequency of relevant findings was low in inadequate echocardiograms and patients and cardiologists had a different perception regarding its usefulness. <![CDATA[Long non-coding RNA HOTAIR promotes UVB-induced apoptosis and inflammatory injury by up-regulation of PKR in keratinocytes]]> Excessive exposure to ultraviolet (UV) rays can cause damage of the skin and may induce cancer, immunosuppression, photoaging, and inflammation. The long non-coding RNA (lncRNA) HOX antisense intergenic RNA (HOTAIR) is involved in multiple human biological processes. However, its role in UVB-induced keratinocyte injury is unclear. This study was performed to investigate the effects of HOTAIR in UVB-induced apoptosis and inflammatory injury in human keratinocytes (HaCaT cells). Quantitative real-time polymerase chain reaction was performed to analyze the expression levels of HOTAIR, PKR, TNF-α, and IL-6. Cell viability was measured using trypan blue exclusion method and cell apoptosis using flow cytometry and western blot. ELISA was used to measure the concentrations of TNF-α and IL-6. Western blot was used to measure the expression of PKR, apoptosis-related proteins, and PI3K/AKT and NF-κB pathway proteins. UVB induced HaCaT cell injury by inhibiting cell viability and promoting cell apoptosis and expressions of IL-6 and TNF-α. UVB also promoted the expression of HOTAIR. HOTAIR suppression increased cell viability and decreased apoptosis and expression of inflammatory factors in UVB-treated cells. HOTAIR also promoted the expression of PKR. Overexpression of HOTAIR decreased cell viability and increased cell apoptosis and expression of inflammatory factors in UVB-treated cells by upregulating PKR. Overexpression of PKR decreased cell viability and promoted cell apoptosis in UVB-treated cells. Overexpression of PKR activated PI3K/AKT and NF-κB pathways. Our findings identified an essential role of HOTAIR in promoting UVB-induced apoptosis and inflammatory injury by up-regulating PKR in keratinocytes. <![CDATA[Interleukin-6 contributes to myocardial damage in pregnant rats with reduced uterine perfusion pressure]]> Preeclampsia is one of the most frequent and difficult illnesses in pregnancy, which jeopardizes both mother and fetus. There are several diagnostic criteria for preeclampsia. However, the preeclampsia-associated myocardial damage has not been described. In this study, we employed reduced uterine perfusion pressure (RUPP) to generate a rat model of preeclampsia for the evaluation of myocardial damage in late-gestation rats. The expressions of cardiac injury markers were analyzed by immunohistochemistry and ELISA. The arterial pressure and myocardial tissue velocities were also measured. The role of interleukin (IL)-6 in RUPP-associated myocardial damage was further explored. The results showed that RUPP rats had significant myocardial damage, as demonstrated by the high expressions of myoglobin, creatine kinase isoenzyme, cardiac troponin I, and brain natriuretic peptide. In addition, RUPP increased the mean arterial pressure and the early transmitral flow velocity to mitral annulus early diastolic velocity ratio (E/Ea). Furthermore, IL-6 deteriorated these abnormalities, whereas inhibition of IL-6 significantly relieved them. In conclusion, our study demonstrated that RUPP rats displayed myocardial damage in an IL-6-dependent manner. <![CDATA[Determination of multidrug resistance mechanisms in <em>Clostridium perfringens</em> type A isolates using RNA sequencing and 2D-electrophoresis]]> In this study, we screened differentially expressed genes in a multidrug-resistant isolate strain of Clostridium perfringens by RNA sequencing. We also separated and identified differentially expressed proteins (DEPs) in the isolate strain by two-dimensional electrophoresis (2-DE) and mass spectrometry (MS). The RNA sequencing results showed that, compared with the control strain, 1128 genes were differentially expressed in the isolate strain, and these included 227 up-regulated genes and 901 down-regulated genes. Bioinformatics analysis identified the following genes and gene categories that are potentially involved in multidrug resistance (MDR) in the isolate strain: drug transport, drug response, hydrolase activity, transmembrane transporter, transferase activity, amidase transmembrane transporter, efflux transmembrane transporter, bacterial chemotaxis, ABC transporter, and others. The results of the 2-DE showed that 70 proteins were differentially expressed in the isolate strain, 45 of which were up-regulated and 25 down-regulated. Twenty-seven DEPs were identified by MS and these included the following protein categories: ribosome, antimicrobial peptide resistance, and ABC transporter, all of which may be involved in MDR in the isolate strain of C. perfringens. The results provide reference data for further investigations on the drug resistant molecular mechanisms of C. perfringens. <![CDATA[Effects of resistance training protocols on nonlinear analysis of heart rate variability in metabolic syndrome]]> Despite the various standard non-linear measurements used in autonomic modulation (AM) assessments usually being applied to long time-series, such analyses can sometimes be applied to shorter term series. To overcome this disadvantage, chaotic global methods were formulated by putting together heart rate variability (HRV) linear methods. Chaos provides information about vegetative function control related to cardiovascular risks. Applying this method can be useful to investigate the complexity of the health condition after resistance training protocols, as a therapeutic intervention in AM in metabolic syndrome individuals (MetS). This study aimed to compare the effects of two resistance training programs (conventional vs functional) in MetS using nonlinear analysis of AM. MetS subjects (n=50) of both sexes aged 40 to 60 years were randomly divided into two programs; a group of 12 people served as a control group. Both groups performed 30 sessions of training. AM was assessed in the chaos domain by chaotic global techniques. The main results showed that both resistance training, functional and conventional, increased chaos when compared to the control group, respectively, observed by chaotic forward parameter (CFP)1 (13.9±17.9 vs 12.8±14.4 vs -2.23±7.96; P≤0.05) and CFP3 (15.4±19.8 vs 21.9±13.2 vs -4.82±11.4; P≤0.05). In addition, 30 sessions of both resistance programs increased chaos, and non-linear analysis enabled discrimination of AM after interventions when compared to the control group. <![CDATA[Association between serotonin 2C receptor gene (<em>HTR2C</em>) polymorphisms and psychopathological symptoms in children and adolescents]]> Serotonin 2C receptors (5HT2C) are involved in serotonin-driven dynamic equilibrium adjustments responsible for homeostatic stability in brain structures that modulate behavior and emotions. Single nucleotide polymorphisms (SNPs) from the serotonin 2C receptor gene (HTR2C) have been associated with several neurological and mental disorders, including abnormalities in cognitive and emotional processes. The aim of this study was to evaluate the association between the rs6318 SNP of the HTR2C gene and behavioral characteristics exhibited by children and adolescents based on the Child Behavior Checklist (CBCL/6-18) inventory. Eighty-five psychiatric outpatients between 8 and 18 years of age underwent genotyping of the rs6318 SNP. The CBCL/6-18 scale was administered to their caregivers. The chi-squared test was used to assess differences in the frequency of C and G alleles of the rs6318 SNP relative to the grouped CBCL/6-18 scores; significance level was 5%. The presence of the G allele of rs6318 was found to be associated with characteristics of aggressive behavior and social problems, and aggressive behavior was found to be associated with heterozygosis in females. These findings contribute to the identification of mental and behavioral phenotypes associated with gene expression. <![CDATA[Exenatide ameliorates hepatic steatosis and attenuates fat mass and <em>FTO</em> gene expression through PI3K signaling pathway in nonalcoholic fatty liver disease]]> Non-alcoholic fatty liver disease (NAFLD) is a common disease associated with metabolic syndrome and can lead to life-threatening complications like hepatic carcinoma and cirrhosis. Exenatide, a glucagon-like peptide-1 (GLP-1) receptor agonist antidiabetic drug, has the capacity to overcome insulin resistance and attenuate hepatic steatosis but the specific underlying mechanism is unclear. This study was designed to investigate the underlying molecular mechanisms of exenatide therapy on NAFLD. We used in vivo and in vitro techniques to investigate the protective effects of exenatide on fatty liver via fat mass and obesity associated gene (FTO) in a high-fat (HF) diet-induced NAFLD animal model and related cell culture model. Exenatide significantly decreased body weight, serum glucose, insulin, insulin resistance, serum free fatty acid, triglyceride, total cholesterol, low-density lipoprotein, aspartate aminotransferase, and alanine aminotransferase levels in HF-induced obese rabbits. Histological analysis showed that exenatide significantly reversed HF-induced lipid accumulation and inflammatory changes accompanied by decreased FTO mRNA and protein expression, which were abrogated by PI3K inhibitor LY294002. This study indicated that pharmacological interventions with GLP-1 may represent a promising therapeutic strategy for NAFLD. <![CDATA[Allantoin as an independent marker associated with carotid intima-media thickness in subclinical atherosclerosis]]> Allantoin is the main product of uric acid oxidation and was found to be augmented in atherosclerotic plaque in human autopsy and in animal models of atherosclerosis. Uric acid is abundant in human plasma and is prone to oxidation in inflammatory conditions such as atherosclerosis. In this study, we found a significant increase in plasma uric acid (P=0.002) and allantoin (P=0.025) in participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) that presented common carotid intima-media thickness (c-IMT) within the 75th percentile (c-IMT≥P75). Multiple linear regression showed an association of c-IMT with uric acid (β=0.0004, P=0.014) and allantoin (β=0.018, P=0.008). This association was independent of age, the traditional risk factor LDL/HDL ratio, and non-traditional risk factors: pulse pressure, neck circumference, and the inflammatory marker myeloperoxidase. The independent and strong association of allantoin with c-IMT shows that it might be a useful marker, along with other traditional risk factors, to evaluate an early stage of atherosclerosis.