Coxsackievirus B5 induced apoptosis of HeLa cells : effects on p53 and SUMO.

Coxsackievirus B5 (CVB5), a human enterovirus of the family Picornaviridae, is a frequent cause of acute and chronic human diseases. The pathogenesis of enteroviral infections is not completely understood, and the fate of the CVB5-infected cell has a pivotal role in this process. We have investigated the CVB5-induced apoptosis of HeLa cells and found that it happens by the intrinsic pathway by a mechanism dependent on the ubiquitin?proteasome system, associated with nuclear aggregation of p53. Striking redistribution of both SUMO and UBC9 was noted at 4 h post-infection, simultaneously with a reduction in the levels of the ubiquitin-ligase HDM2. Taken together, these results suggest that CVB5 infection of HeLa cells elicit the intrinsic pathway of apoptosis by MDM2 degradation and p53 activation, destabilizing protein sumoylation, by a mechanism that is dependent on a functional ubiquitin?proteasome system

The impact of sequence length and number of sequences on promoter prediction performance.

Background: The advent of rapid evolution on sequencing capacity of new genomes has evidenced the need for data analysis automation aiming at speeding up the genomic annotation process and reducing its cost. Given that one important step for functional genomic annotation is the promoter identification, several studies have been taken in order to propose computational approaches to predict promoters. Different classifiers and characteristics of the promoter sequences have been used to deal with this prediction problem. However, several works in literature have addressed the promoter prediction problem using datasets containing sequences of 250 nucleotides or more. As the sequence length defines the amount of dataset attributes, even considering a limited number of properties to characterize the sequences, datasets with a high number of attributes are generated for training classifiers. Once high dimensional datasets can degrade the classifiers predictive performance or even require an infeasible processing time, predicting promoters by training classifiers from datasets with a reduced number of attributes, it is essential to obtain good predictive performance with low computational cost. To the best of our knowledge, there is no work in literature that verified in a systematic way the relation between the sequences length and the predictive performance of classifiers. Thus, in this work, we have evaluated the impact of sequence length variation and training dataset size (number of sequences) on the predictive performance of classifiers. Results: We have built sixteen datasets composed of different sized sequences (ranging in length from 12 to 301 nucleotides) and evaluated them using the SVM, Random Forest and k NN classifiers. The best predictive performances reached by SVM and Random Forest remained relatively stable for datasets composed of sequences varying in length from 301 to 41 nucleotides, while k-NN achieved its best performance for the dataset composed of 101 nucleotides. We have also analyzed, using sequences composed of only 41 nucleotides, the impact of increasing the number of sequences in a dataset on the predictive performance of the same three classifiers. Datasets containing 14,000, 80,000, 100,000 and 120,000 sequences were built and evaluated. All classifiers achieved better predictive performance for datasets containing 80,000 sequences or more. Conclusion: The experimental results show that several datasets composed of shorter sequences achieved better predictive performance when compared with datasets composed of longer sequences, and also consumed a significantly shorter processing time. Furthermore, increasing the number of sequences in a dataset proved to be beneficial to the predictive power of classifiers

NEDD8 conjugation in Schistosoma mansoni : genome analysis and expression profiles.

NEDD8 is an ubiquitin-like molecule that covalently binds to target proteins through an enzymatic cascade analogous to ubiquitylation. This modifier is known to bind to p53 and p73, as well as all Cullin family proteins, which are essential components of Skp1/Cul-1/F-box protein (SCF)-like Ub ligase complexes. Here, we focused on a genomic analysis of the genes involved in the NEDD8 conjugation pathway in Schistosoma mansoni. The results revealed seven genes related to NEDD8 conjugation that are conserved in Schistosoma japonicum, Caenorhabditis elegans, Drosophila melanogaster and Homo sapiens. We performed quantitative RT-PCR (qRT-PCR), which showed differential profiles for Smnedd8, Smapp1, Smuba3, Smube2f, Smdcn1, Smrbx and Smsenp8 throughout the life cycle of S. mansoni. Upregulation was observed in 3-day-old schistosomula and adult worms for all analysed genes. We also analysed the transcription levels of Cullin family members Smp63 and Smp73, and observed upregulation in early schistosomula, while cercariae and adult worms showed expression levels similar to one another. Taken together, these results suggest that the NEDDylation/ DeNEDDylation pathway controls important cellular regulators during worm development from cercariae to schistosomula and, finally, to adult

Oral Ang-(1-7) treatment improves white adipose tissue remodeling and hypertension in rats with metabolic syndrome.

Objective: Angiotensin (Ang)-(1-7) has preventive effects on metabolic syndrome (MetS). The aim of this study was to evaluate the therapeutic effect of oral Ang-(1-7) on mean arterial pressure (MAP), insulin resistance (IR), inflammatory process, and remodeling of white adipose tissue (WAT) in rats with establishedMetS. Methods: Rats were subjected to control (CT; AIN-93M) or high-fat (HF) diets for 13 wk to induce MetS and treated with Ang-(1-7) or vehicle (V) for the last 6 wk. At the end of 13 wk, MAP, biochemical and histological parameters, and uncoupling protein (UCP) and inflammatory gene expression were determined by quantitative reverse transcription polymerase chain reaction. Results: HF-V rats showed increased visceral fat deposition, inflammatory cytokine expression, hyperplasia, and hypertrophy in retroperitoneal (WAT) and brown adipose tissue (BAT). Additionally, the gastrocnemius muscle reduced UCP-3 and increased the UCP-1 expression in BAT. HF-V also elevated levels of plasma insulin, glucose, homeostatic model assessment (HOMA) of IR and HOMA-b, and increased body mass, adiposity, and MAP. Ang-(1-7) treatment in rats with MetS [HF-Ang-(1-7)] reduced WAT area, number of adipocytes, and expression of proinflammatory adipokines in WAT and BAT and increased UCP-3 in gastrocnemius muscle and UCP-1 expression in BAT compared with the HF-V group. These events prevented body mass gain, reduced adiposity, and normalized fasting plasma glucose, insulin levels, HOMA-IR, HOMA-b, and MAP. Conclusion: Data from the present study demonstrated that oral Ang-(1-7) treatment is effective in restoring biochemical parameters and hypertension in established MetS by improving hypertrophy and hyperplasia in WAT and inflammation in adipose tissue, and regulating metabolic processes in the gastrocnemius muscle and BAT

Antioxidant effects of oral Ang-(1-7) restore insulin pathway and RAS components ameliorating cardiometabolic disturbances in rats.

In prevention studies of metabolic syndrome (MetS), Ang-(1-7) has shown to improve the insulin signaling. We evaluated the HP?CD/Ang-(1-7) treatment on lipid metabolism, renin-angiotensin system (RAS) components, oxidative stress, and insulin pathway in the liver and gastrocnemius muscle and hepatic steatosis in rats with established MetS. After 7 weeks of high-fat (FAT) or control (CT) diets, rats were treated with cyclodextrin (HP?CD) or HP?CD/Ang-(1-7) in the last 6 weeks. FATHP?CD/ empty rats showed increased adiposity index and body mass, gene expression of ACE/ANG II/AT1R axis, and oxidative stress. These results were accompanied by imbalances in the insulin pathway, worsening of liver function, hyperglycemia, and dyslipidemia. Oral HP?CD/Ang-(1-7) treatment decreased ACE and AT1R, increased ACE2 gene expression. in the liver, and restored thiobarbituric acid reactive substances (TBARS), catalase (CAT), superoxide dismutase (SOD), insulin receptor substrate (Irs-1), glucose transporter type 4 (GLUT4), and serine/threonine kinase 2 (AKT-2) gene expression in the liver and gastrocnemius muscle improving hepatic function, cholesterol levels, and hyperglycemia in MetS rats. Overall, HP?CD/Ang-(1-7) treatment restored the RAS components, oxidative stress, and insulin signaling in the liver and gastrocnemius muscle contributing to the establishment of blood glucose and lipid homeostasis in MetS rats

Physical activity prevents alterations in mitochondrial ultrastructure and glucometabolic parameters in a high-sugar diet model.

Endurance exercise is a remarkable intervention for the treatment of many diseases. Mitochondrial changes on skeletal muscle are likely important for many of the benefits provided by exercise. In this study, we aimed to evaluate the effects that a regular physical activity (swimming without workload) has on mitochondrial morphological alterations and glucometabolic parameters induced by a high-sugar diet (HSD). Weaned male Wistar rats fed with a standard diet or a HSD (68% carbohydrate) were subjected to 60 minutes of regular physical activity by swimming (without workload) for four- (20 sessions) or eight-week (40 sessions) periods. After training, animals were euthanized and the sera, adipose tissues, and skeletal muscles were collected for further analysis. The HSD increased body weight after an 8- week period; it also increased the fat pads and the adipose index, resulting in glucose intolerance and insulin resistance (IR). Transmission electron microscopy showed an increase in alterations of mitochondrial ultrastructure in the gastrocnemius muscle, as well as a decrease in superoxide dismutase (SOD) activity, and an increase in protein carbonylation. Regular physical activity partially reverted these alterations in rats fed a HSD, preventing mitochondrial morphological alterations and IR. Moreover, we observed a decrease in Pgc1? expression (qPCR analysis) in STD-EXE group and a less pronounced reduction in HSD-EXE group after an 8-week period. Thus, regular physical activity (swimming without workload) in rats fed a HSD can prevent mitochondrial dysfunction and IR, highlighting the crucial role for physical activity on metabolic homeostasis

Mechanisms of manganese bioremediation by microbes : an overview.

Although an important micronutrient for many living organisms, manganese (Mn) can become a health and environmental problem at high concentrations. The element is usually found in wastewaters and drainages of different industrial sectors and its removal is notoriously difficult because of the high stability of theMn (II) ion in aqueous solutions. The treatment ofMn-laden wastewaters may include microorganisms that catalyze Mn oxidation by either enzymatic or non-enzymatic pathways. In this context, this mini-review discusses the mechanisms by which fungi and bacteria promoteMn bioremediation

Manganese alters expression of proteins involved in the oxidative stress of Meyerozyma guilliermondii.

Organisms, in general, respond to environmental stress by altering their pattern of protein expression (proteome), as an alternative to growing in stressful conditions. A strain of Meyerozyma guilliermondii resistant to manganese was isolated from a sample of water collected from mine drainage in southeastern Minas Gerais (Brazil), and demonstrated manganese detoxification capacity. Protein extracts containing the soluble fractions were obtained after growth of the strain in the absence and presence of MnSO4. Tryptic peptides recovered from samples were analyzed by liquid chromatography coupled to mass spectrometry (LC-MS/MS). Shotgun/bottomup analyses of the soluble fractions revealed a total of 1257 identified molecules. Treatment with Mn did not affect the growth of yeast but induced changes in the protein profile, with 117 proteins expressed in the absence of Mn and 69 expressed only in its presence. Most of these are annotated as related to DNA repair, oxidoreductase activity, and remodeling of gene expression. This is the first proteomic report of M. guilliermondii, with promising characteristics for Mn bioremediation, and the first of the genus Meyerozyma. This proteomic characterization may help in the understanding of molecular regulatory mechanisms associated with tolerance to excess Mn, and the potential use of biomass in bioremediation processes. Significance: Environmental pollution by heavy metals such as manganese (Mn2+) has increased as it is a byproduct of the mining industry and a potential environmental contaminant. Many studies have explored the use of bacteria for manganese bioremediation, but yeasts have emerged as a promising alternative, displaying faster growth and greater removal efficiency. Previous works of our laboratory showed that Meyerozyma guilliermondii, a non-pathogenic haploid yeast (ascomycete), has excellent removal and accumulation capacity of Mn2+, potentially useful in bioremediation. Nowadays efforts have been devoted to understanding the physiology of metal hyperaccumulation to gain insights into the molecular basis of hyperaccumulation. To obtain a comprehensive understanding of the molecular mechanism of Mn2+ hyperaccumulation in M. guilliermondii, proteomic approaches were employed yielding the first compositional proteomic map of total soluble proteins and their differential expression in the presence of Mn2+. We believe our findings are of biotechnological interest concerning the utilization of M. guilliermondii for bioremediation purposes

Manganese alters expression of proteins involved in the oxidative stress of Meyerozyma guilliermondii.

Organisms, in general, respond to environmental stress by altering their pattern of protein expression (proteome), as an alternative to growing in stressful conditions. A strain of Meyerozyma guilliermondii resistant to manganese was isolated from a sample of water collected from mine drainage in southeastern Minas Gerais (Brazil), and demonstrated manganese detoxification capacity. Protein extracts containing the soluble fractions were obtained after growth of the strain in the absence and presence of MnSO4. Tryptic peptides recovered from samples were analyzed by liquid chromatography coupled to mass spectrometry (LC-MS/MS). Shotgun/bottom-up analyses of the soluble fractions revealed a total of 1257 identified molecules. Treatment with Mn did not affect the growth of yeast but induced changes in the protein profile, with 117 proteins expressed in the absence of Mn and 69 expressed only in its presence. Most of these are annotated as related to DNA repair, oxidoreductase activity, and remodeling of gene expression. This is the first proteomic report of M. guilliermondii, with promising characteristics for Mn bioremediation, and the first of the genus Meyerozyma. This proteomic characterization may help in the understanding of molecular regulatory mechanisms associated with tolerance to excess Mn, and the potential use of biomass in bioremediation processes. Significance: Environmental pollution by heavy metals such as manganese (Mn2+) has increased as it is a by-product of the mining industry and a potential environmental contaminant. Many studies have explored the use of bacteria for manganese bioremediation, but yeasts have emerged as a promising alternative, displaying faster growth and greater removal efficiency. Previous works of our laboratory showed that Meyerozyma guilliermondii, a non-pathogenic haploid yeast (ascomycete), has excellent removal and accumulation capacity of Mn2+, potentially useful in bioremediation. Nowadays efforts have been devoted to understanding the physiology of metal hyperaccumulation to gain insights into the molecular basis of hyperaccumulation. To obtain a comprehensive understanding of the molecular mechanism of Mn2+ hyperaccumulation in M. guilliermondii, proteomic approaches were employed yielding the first compositional proteomic map of total soluble proteins and their differential expression in the presence of Mn2+. We believe our findings are of biotechnological interest concerning the utilization of M. guilliermondii for bioremediation purposes

A sulfate-reducing bacterium with unusual growing capacity in moderately acidic conditions.

The use of sulfate-reducing bacteria (SRB) is a cost-effective route to treat sulfate- contaminated waters and precipitate metals. The isolation and characterization of a SRB strain from an AMD in a Brazilian tropical region site was carried out. With a moderately acidic pH (5.5), the C.1 strain began its growth and with continued growth, modified the pH accordingly. The strain under these conditions reduced sulfate at the same rate as an experiment performed using an initial pH of 7.0. The dsrB gene-based molecular approach was used for the characterization of this strain and its phylogenetic affiliation was similar to genus Desulfovibrio sp. The results show an SRB isolate with unexpected sulfate reducing capacity in moderately acidic conditions, bringing new possibilities for the treatment of AMD, as acid water would be neutralized to a mildly acidic condition