Invasion of glioma cells through confined space requires membrane tension regulation and mechano-electrical coupling via Plexin-B2.

Glioblastoma (GBM) is a malignant brain tumor with uncontrolled invasive growth. Here, we demonstrate how GBM cells usurp guidance receptor Plexin-B2 to gain biomechanical plasticity for polarized migration through confined space. Using live-cell imaging to track GBM cells negotiating microchannels, we reveal active endocytosis at cell front and filamentous actin assembly at rear to propel GBM cells through constrictions. These two processes are interconnected and governed by Plexin-B2 that orchestrates cortical actin and membrane tension, shown by biomechanical assays. Molecular dynamics simulations predict that balanced membrane and actin tension are required for optimal migratory velocity and consistency. Furthermore, Plexin-B2 mechanosensitive function requires a bendable extracellular ring structure and affects membrane internalization, permeability, phospholipid composition, as well as inner membrane surface charge. Together, our studies unveil a key element of membrane tension and mechanoelectrical coupling via Plexin-B2 that enables GBM cells to adapt to physical constraints and achieve polarized confined migration.

Contrasting patterns of foraging behavior in neotropical stingless bees using pollen and honey metabarcoding.

Stingless bees are major flower visitors in the tropics, but their foraging preferences and behavior are still poorly understood. Studying stingless bee interactions with angiosperms is methodologically challenging due to the high tropical plant diversity and inaccessibility of upper canopy flowers in forested habitats. Pollen DNA metabarcoding offers an opportunity of assessing floral visitation efficiently and was applied here to understand stingless bee floral resources spectra and foraging behavior. We analyzed pollen and honey from nests of three distantly related stingless bee species, with different body size and social behavior: Melipona rufiventris, Scaptotrigona postica and Tetragonisca angustula. Simultaneously, we evaluate the local floristic components through seventeen rapid botanical surveys conducted at different distances from the nests. We discovered a broad set of explored floral sources, with 46.3 plant species per bee species in honey samples and 53.67 in pollen samples. Plant families Myrtaceae, Asteraceae, Euphorbiaceae, Melastomataceae and Malpighiaceae dominated the records, indicating stingless bee preferences for abundant resources that flowers of these families provide in the region. Results also reinforce the preference of stingless bees for forest trees, even if only available at long distances. Our high-resolution results encourage future bee-plant studies using pollen and honey metabarcoding in hyper-diverse tropical environments.

Paraprobiotics strains accelerate wound repair by stimulating re-epithelialization of NIH-3T3 cells, decreasing inflammatory response and oxidative stress.

The present study aimed to evaluate the potential and specificity of the inflammatory and antioxidant response of Microbe-Associated Molecular Patterns (MAMPs) in NIH-3T3 fibroblast cells, as well as in the healing process of skin wounds. Cells (NIH-3T3) were cultivated in supplemented specific medium. NIH-3T3 cells were treated with MAMPs (Bifidobacterium lactis or Lactobacillus casei or Lactobacillus gasseri or Lactobacillus paracasei or Streptococcus thermophilus), at two concentrations and insulted with LPS or H2O2. Cell viability, myeloperoxidase activity, nitrite/nitrate, oxidative damage and inflammatory parameters were measured. In addition, scratch assay was performed. Significant scratch closure was observed after 24 h and 48 h, and the effect of 0.1 g/mL MAMPs on wound healing was found to be highly statistically significant. In the viability cellular assay, Lactobacillus showed better response in 0.1 g/mL dose, whereas B. lactis and S. thermophilus showed better response in 0.01 g/mL dose. There was reduction in IL-6 and IL-1ß levels in all treatments insulted with LPS. MAMP's showed preventive efficacy in reducing the effects caused by LPS. The MAMP's action in decreasing the production of ROS, inflammatory activity and increasing cell viability, besides significant cell proliferation during wound healing processes suggests remodeling mechanisms and new possibilities for wound healing.

Spectroscopic Detection of Biosignatures in Natural Ice Samples as a Proxy for Icy Moons.

Some of the icy moons of the solar system with a subsurface ocean, such as Europa and Enceladus, are the targets of future space missions that search for potential extraterrestrial life forms. While the ice shells that envelop these moons have been studied by several spacecrafts, the oceans beneath them remain unreachable. To better constrain the habitability conditions of these moons, we must understand the interactions between their frozen crusts, liquid layers, and silicate mantles. To that end, astrobiologists rely on planetary field analogues, for which the polar regions of Earth have proven to be great candidates. This review shows how spectroscopy is a powerful tool in space missions to detect potential biosignatures, in particular on the aforementioned moons, and how the polar regions of the Earth are being used as planetary field analogues for these extra-terrestrial environments.

Relationship between physical exercise and COVID-19 (SARS-CoV-2): systematic review.

Background: The SARS-CoV virus is a precursor to the SARS-CoV-2 virus (COVID-19) and has caused millions of deaths worldwide. Although exercise can be a non-pharmacological means for the prevention and treatment of various diseases, the effects on COVID-19 patients are not yet completely clear. Aims: The aim of this study was to investigate the relationship between physical exercise and symptoms caused by COVID-19. Methods: The present systematic review was sent for evaluation and received the PROSPERO registration protocol-CRD42021257475. The search for studies related to health and physical exercise was carried out in the following databases; the "National Library in Medicine MEDLINE-Ovid", "Embase", "Web of Science", "SportDiscus-Ebsco", and "Scopus". Results: Ten articles were included in the systematic review and the findings demonstrated the protective effects of physical exercise in patients with COVID-19. These effects were observed both in symptoms and in the period of hospitalization. In addition, the results show that the benefits of physical exercise seem to collaborate both in an individual manner and as an alternative to drug therapy. Finally, it was possible to verify the effect of physical exercise on variables, such as quality of life, cardiorespiratory capacity, and immunological biomarkers, and on the symptoms of the new Coronavirus. Conclusions: It is possible to conclude that physical exercise can be a component for the treatment of COVID-19. In addition, it could help to reduce the symptoms and severity of COVID-19, and may be considered as an adjunct to drug therapy in patients contaminated with SARS-CoV-2.

Effects of different probiotic strains B. lactis, L. rhamnosus and L. reuteri on brain-intestinal axis immunomodulation in an endotoxin-induced inflammation.

The study evaluated the effects of supplementation with three different probiotic strains Bifidobacterium lactis (LACT GB™), Lactobacillus rhamnosus (RHAM GB™) and Lactobacillus reuteri (REUT GB™) on brain-intestinal immunomodulation in an animal model of LPS-induced inflammation. Fifty mice Balb/C were distributed into five groups: control; lipopolysaccharide (LPS); LPS + B. lactis (LACT GB™); LPS + L. rhamnosus (RHAM GB™); and LPS + L. reuteri (REUT GB™). The animals were supplemented with their respective probiotic microorganisms daily, for 30 days, at a concentration of 1 × 109 CFU/animal/day. After 30 days of supplementation, animals received the inflammatory insult by LPS (15 mg/kg). Behavioral tests, oxidative stress and inflammation were performed, as well as gut and brain histology. In the behavioral test, LPS + B. lactis group was less anxious than the other groups. Serum interleukin IL-1ß and IL-6 levels increased in all groups that received the LPS insult, and there was a reduction in inflammation in the supplemented groups when compared to the LPS group in brain and gut. There is a reduction in myeloperoxidase activity and oxidative stress in groups supplemented with probiotics. In intestine histological analysis occurs damage to the tissue integrity in the LPS group, in the other hand, occurs preservation of integrity in the probiotic supplemented animals. In the brain, infiltrates of perivascular inflammatory cells can be seen in the LPS group. The three probiotic studies showed efficient immunomodulating activity and ensured integrity of the intestinal barrier function, even after the severe insult by LPS. These results show the important role of probiotics in the gut-brain axis. Graphical abstract illustratively represents the gut-brain axis and how different probiotic strains influence the immunomodulatory response releasing different pro- and anti-inflammatory cytokines, and their role in the balance of dysbiosis.

Whole-Genome Sequencing and Comparative Genomic Analysis of Antimicrobial Producing Streptococcus lutetiensis from the Rumen.

Antimicrobial peptides (AMPs) can efficiently control different microbial pathogens and show the potential to be applied in clinical practice and livestock production. In this work, the aim was to isolate AMP-producing ruminal streptococci and to characterize their genetic features through whole-genome sequencing. We cultured 463 bacterial isolates from the rumen of Nelore bulls, 81 of which were phenotypically classified as being Streptococcaceae. Five isolates with broad-range activity were genome sequenced and confirmed as being Streptococcus lutetiensis. The genetic features linked to their antimicrobial activity or adaptation to the rumen environment were characterized through comparative genomics. The genome of S. lutetiensis UFV80 harbored a putative CRISPR-Cas9 system (Type IIA). Computational tools were used to discover novel biosynthetic clusters linked to the production of bacteriocins. All bacterial genomes harbored genetic clusters related to the biosynthesis of class I and class II bacteriocins. SDS-PAGE confirmed the results obtained in silico and demonstrated that the class II bacteriocins predicted in the genomes of three S. lutetiensis strains had identical molecular mass (5197 Da). These results demonstrate that ruminal bacteria of the Streptococcus bovis/equinus complex represent a promising source of novel antimicrobial peptides.

Comparative effects of fresh and sterile fecal microbiota transplantation in an experimental animal model of necrotizing enterocolitis.

INTRODUCTION: Necrotizing Enterocolitis (NEC) is a serious intestinal disease that affects premature neonates, causing high mortality, despite the technological development in neonatal intensive care, with antibiotics, parenteral nutrition, surgery, and advanced life support. The correction of dysbiosis with fecal microbiome transplantation (FMT) has shown beneficial effects in experimental models of the disease. The different forms of administration and conservation of FMT and mixed results depending on several factors lead to questions about the mechanism of action of FMT. This study aimed to compare the effectiveness of fresh, sterile FMT and probiotic treatment under parameters of inflammation, oxidative stress, and tissue damage in a neonatal model of NEC. METHODS: One-day-old Wistar rats were used to induce NEC model. Animals were divided in five groups: Control + saline; NEC + saline; NEC + fresh FMT; NEC + sterile FMT and NEC+ probiotics. Parameters of inflammatory response and oxidative damage were measured in the gut, brain, and serum. It was also determined gut histopathological alterations. RESULTS: Proinflammatory cytokines were increased in the NEC group, and IL-10 levels decreased in the gut, brain, and serum. Fresh and sterile FMT decreased inflammation when compared to the use of probiotics. Oxidative and histological damage to the intestine was apparent in the NEC group, and both FMT treatments had a protective effect. CONCLUSION: Fresh and sterile FMT effectively reduced the inflammatory response, oxidative damage, and histological alterations in the gut and brain compared to an experimental NEC model.

Patterns of airway obstruction of non-acquired origin in children with and without major congenital anomalies.

Major congenital anomalies are known to play a role in the management and prognosis of airway obstruction. Most studies assess acquired forms of airway obstruction. Data on congenital or otherwise non-acquired forms of airway obstruction is sparse. In this retrospective, single-institution cohort study, we sought to evaluate and compare the patterns of airway obstruction in children with and without major congenital anomalies, and to assess the impact of management and outcome, irrespective of aetiology. Fifty-five patients were included, 23 with and 32 without underlying major congenital anomalies. Multilevel airway obstruction (usually affecting the nasopharynx, oropharynx, and the trachea) was more common in children with congenital anomalies (91% vs. 41%, p < .001). Consequently, these children required more frequent and earlier surgical management, especially tracheostomy and adenotonsillar surgery.Conclusions: Major congenital anomalies are associated with multilevel airway obstruction and poor functional prognosis. A simple clinical definition considering impact of major congenital anomalies on development and growth may help guide management plans following endoscopic evaluation of the entire airway and flanked by multidisciplinary discussions. What is Known: • Children with major comorbidities display increased disease severity and more prevalent multilevel airway obstruction • Previous studies include both children with acquired and non-acquired forms of airway obstruction; therefore, the actual impact major comorbidities in children with non-acquired causes of airway obstruction remain unclear. What is New: • A total of 42% children in this study population had major comorbidities with and impact on growth and/or psychomotor development, with a higher prevalence of multilevel airway obstruction and worse rates of functional improvement/recovery. • Children with major comorbidities require tracheostomy more often and earlier than those without major comorbidities, and remain tracheostomy-dependent for a longer time.

Influence of Chronic Exposure to Exercise on Heart Rate Variability in Children and Adolescents Affected by Obesity: A Systematic Review and Meta-Analysis.

BACKGROUND: Sedentary lifestyles are increasingly common amongst children, and insufficient physical activity is a global epidemic estimated to contribute to future incapacities and potential deaths. OBJECTIVE: We aimed to increase the amount of evidence concerning the effect of chronic exposure to exercise on heart rate variability in children and adolescents affected by obesity. METHODS: A systematic review commenced following the PRISMA guidelines developed by Web of Science, Virtual Health Library, PubMed, Cochrane Library, Embase, Ovid, Medline Complete, and Scopus using keywords obtained from the Descriptors in Health Sciences and Medical Subject Headlines (MeSH) terms. We considered (1) Population: Pediatric individuals affected by obesity; (2) Intervention: Exercise; (3) Control: Pre-intervention and sedentary; (4) Outcomes: Clearly presented primary parameters; and (5) Studies: Clinical trials, case controls, case reports, and case series. RESULTS: 11 articles were involved and predominantly included procedures observed during approximately 12 weeks with a distribution of three sessions per week, each session being 30-60 min of aerobic exercise; additionally, the exercise grades were typically completed at a percentage of subjects' maximum heart rates. The meta-analyses displayed a significant effect on the domains of time (R-R interval, SDNN, rMSSD), frequency (HF ms2, HF (n.u.), LF/HF), and the non-linear index (SD1). CONCLUSIONS: Chronic exposure to exercise influences heart rate variability in children and adolescents affected by obesity by elevating the variability and parasympathetic activity and improving the sympathetic-vagal balance. Exercises should be recommended for the improvement of cardiac autonomic modulation to prevent the likelihood of further chronic diseases.

Plexin-B2 orchestrates collective stem cell dynamics via actomyosin contractility, cytoskeletal tension and adhesion.

During morphogenesis, molecular mechanisms that orchestrate biomechanical dynamics across cells remain unclear. Here, we show a role of guidance receptor Plexin-B2 in organizing actomyosin network and adhesion complexes during multicellular development of human embryonic stem cells and neuroprogenitor cells. Plexin-B2 manipulations affect actomyosin contractility, leading to changes in cell stiffness and cytoskeletal tension, as well as cell-cell and cell-matrix adhesion. We have delineated the functional domains of Plexin-B2, RAP1/2 effectors, and the signaling association with ERK1/2, calcium activation, and YAP mechanosensor, thus providing a mechanistic link between Plexin-B2-mediated cytoskeletal tension and stem cell physiology. Plexin-B2-deficient stem cells exhibit premature lineage commitment, and a balanced level of Plexin-B2 activity is critical for maintaining cytoarchitectural integrity of the developing neuroepithelium, as modeled in cerebral organoids. Our studies thus establish a significant function of Plexin-B2 in orchestrating cytoskeletal tension and cell-cell/cell-matrix adhesion, therefore solidifying the importance of collective cell mechanics in governing stem cell physiology and tissue morphogenesis.

Exploring machine learning to predict depressive relapses of bipolar disorder patients.

BACKGROUND: Bipolar disorder (BD) is a chronic mood disorder characterized by recurrent episodes of mania or hypomania and depression, expressed by changes in energy levels and behavior. However, most of relapse studies use evidence-based approaches with statistical methods. With the advance of the precision medicine this study aims to use machine learning (ML) approaches as a possible predictor in depressive relapses in BD. METHOD: Four accepted and well used ML algorithms (Support Vector Machines, Random Forests, Naïve Bayes, and Multilayer Perceptron) were applied to the Systematic Treatment Enhancement Program for Bipolar Disorder (STEP-BD) dataset in a cohort of 800 patients (507 patients presented depressive relapse and 293 did not), who became euthymic during the study and were followed for one year. RESULTS: The ML algorithms presented reasonable performance in the prediction task, ranging from 61 to 80% in the F-measure. The Random Forest algorithm obtained a higher average of performance (Relapse Group 68%; No Relapse Group 74%). The three most important mood symptoms observed in the relapse visit (Random Forest) were: interest; depression mood and energy. LIMITATIONS: Social and psychological parameters such as marital status, social support system, personality traits, might be an important predictor in depressive relapses, although we did not compute this data in our study. CONCLUSIONS: Our findings indicate that applying precision medicine models by means of machine learning in BD studies could be feasible as a sensible approach to better support medical decision-making in the BD treatment and prevention of future relapses.

Influence of Different Types of Corticosteroids on Heart Rate Variability of Individuals with Duchenne Muscular Dystrophy-A Pilot Cross Sectional Study.

Individuals with Duchenne Muscular Dystrophy (DMD) have an impairment of cardiac autonomic function categorized by parasympathetic reduction and sympathetic predominance. The objective of this study was to assess the cardiac autonomic modulation of individuals with DMD undergoing therapy with Prednisone/Prednisolone and Deflazacort and compare with individuals with DMD without the use of these medications and a typically developed control group. Methods: A cross-sectional study was completed, wherein 40 boys were evaluated. The four treatment groups were: Deflazacort; Prednisone/Prednisolone; no corticoid use; and typical development. Heart Rate Variability (HRV) was investigated via linear indices (Time Domain and Frequency Domain) and non-linear indices Results: The results of this study revealed that individuals with DMD undertaking pharmacotherapies with Prednisolone demonstrated HRV comparable to the Control Typically Developed (CTD) group. In contrast, individuals with DMD undergoing pharmacotherapies with Deflazacort achieved lower HRV, akin to individuals with DMD without any medications, as demonstrated in the metrics: RMSSD; LF (n.u.), HF (n.u.), LF/HF; SD1, α1, and α1/α2, and a significant effect for SD1/SD2; %DET and Ratio; Shannon Entropy, 0 V%, 2 LV% and 2 ULV%. Conclusions: Corticosteroids have the potential to affect the cardiac autonomic modulation in adolescents with DMD. The use of Prednisone/Prednisolone appears to promote improved responses in terms of sympathovagal activity as opposed to Deflazacort.

A Educação Física na BNCC: desafios da escola republicana / Physical Education at BNCC: challenges of the republican school / Educación Física en BNCC: desafíos de la escuela republicana

Este estudo consiste em um ensaio teórico que apresenta reflexões acerca das possibilidades e dos desafios impostos pela Base Nacional Comum Curricular. Para tanto, propõe uma discussão sobre república e democracia, localizando a escola como uma instituição formativa necessária para o funcionamento da sociedade. Procura, por fim, analisar o processo de elaboração da base destacando que, embora a efetivação de um currículo comum seja importante para a legitimação da Educação Física como um componente curricular necessário para a escola republicana, o processo final da construção do documento ocorreu de modo pouco democrático, pondo em xeque sua legitimidade.

The present study consists of a theoretical essay that presents reflections on the possibilities and challenges imposed by the National Common Curricular Base. For this, it proposes a discussion on republic and democracy, locating the school as a training institution necessary for the functioning of society. Finally, we seek to analyze the process of preparing the base, highlighting that although the implementation of a common curriculum is important for the legitimation of Physical Education as a necessary curricular component for the republican school, the final process of the construction of the document occurred in an undemocratic way, challenging its legitimacy.

El presente estudio consiste en un ensayo teórico que presenta reflexiones sobre las posibilidades y desafíos que impone la Base Curricular Común Nacional. Para ello propone una discusión sobre república y democracia, ubicando a la escuela como una institución de formación necesaria para el funcionamiento de la sociedad. Finalmente, buscamos analizar el proceso de elaboración de la base, resaltando que, si bien la implementación de un currículo común es importante para la legitimación de la Educación Física como componente curricular necesario para la escuela republicana, se dio el proceso final de construcción del documento. de forma antidemocrática, desafiando su legitimidad.

Aerobic Training in Young Men Increases the Transfer of Cholesterol to High Density Lipoprotein In Vitro: Impact of High Density Lipoprotein Size.

Exercise training not only improves the plasma lipid profile but also reduces risk of developing coronary heart disease. We investigate whether plasma lipids and high density lipoprotein (HDL) metabolism are affected by aerobic training and whether the high-density lipoprotein cholesterol (HDL-C) levels at baseline influence exercise-induced changes in HDL. Seventy-one male sedentary volunteers were evaluated and allocated in two subgroups, according to the HLD-C levels (< or >40 mg/dL). Participants underwent an 18-week aerobic training period. Blood was sampled before and after training for biochemical analysis. Plasma lipids, apolipoproteins, HDL diameter, and VO2 peak were determined. Lipid transfers to HDL were determined in vitro by incubating plasma samples with a donor lipid artificial nanoemulsion. After the 18-week period of aerobic training, the VO2 peak increased, while the mean body mass index (BMI) decreased. HDL-C concentration was higher after the training period, but low-density lipoprotein cholesterol (LDL-C) and non-HDL-C did not change. The transfer of esterified cholesterol and phospholipids was greater after exercise training, but the triacylglycerol and unesterified cholesterol transfers were unchanged. The HDL particle diameter increased after aerobic training in all participants. When the participants were separated in low-HDL and normal-HDL groups, the postaerobic exercise increment in HDL-C was higher in the low-HDL group, while the transfer of esterified cholesterol was lower. In conclusion, aerobic exercise training increases the lipid transfers to HDL, as measured by an in vitro method, which possibly contributes to the classical elevation of the HDL-C associated with training.

Predominant polarity classification and associated clinical variables in bipolar disorder: A machine learning approach.

BACKGROUND: Bipolar disorder (BD) is a severe psychiatric disorder characterized by periodic episodes of manic and depressive symptomatology. Predominant polarity (PP) appears to be an important specifier of BD. The present study employed machine learning (ML) algorithms to accurately determine a patient´s PP without the inclusion of number and polarity of past episodes, while exploring associations between PP and demographic and clinical variables. METHODS: From a cohort of 148 BD patients, demographic and clinical variables were collected using a customized questionnaire and the SCID-CV. The algorithm employed was the Random-Forest method. The algorithm was programed to classify patients into either depressive or manic predominant polarities and to reveal which variables were associated to the specifier. RESULTS: The algorithm attained an AUC ROC of 74.72% (95% CI = 72.29-77.15%) in classifying patients into either manic or depressive PP. The variables selected by the algorithm were: (1) age at first depressive episode; (2) number of hospitalizations; (3) BD Type II; (4) manic onset; (5) delusions; (6) psychotic features at onset; (7) tobacco addiction; (8) family history of BD; (9) hallucinations; and (10) comorbid anxiety disorders, (11) alcohol dependence, (12) eating disorders and (13) substance dependence. LIMITATIONS: The study is limited due to the small sample size, the inclusion of only self-reported and clinician-observed clinical variables and its cross-sectional design. DISCUSSION: The results suggest that the ML approach could be effective in determining a patient´s PP. Furthermore, although not previously reported, some variables, such as tobacco use and comorbid eating disorders, appear to be closely associated with PP.

Internet use by older adults with bipolar disorder: international survey results.

BACKGROUND: The world population is aging and the number of older adults with bipolar disorder is increasing. Digital technologies are viewed as a framework to improve care of older adults with bipolar disorder. This analysis quantifies Internet use by older adults with bipolar disorder as part of a larger survey project about information seeking. METHODS: A paper-based survey about information seeking by patients with bipolar disorder was developed and translated into 12 languages. The survey was anonymous and completed between March 2014 and January 2016 by 1222 patients in 17 countries. All patients were diagnosed by a psychiatrist. General estimating equations were used to account for correlated data. RESULTS: Overall, 47% of older adults (age 60 years or older) used the Internet versus 87% of younger adults (less than 60 years). More education and having symptoms that interfered with regular activities increased the odds of using the Internet, while being age 60 years or older decreased the odds. Data from 187 older adults and 1021 younger adults were included in the analysis excluding missing values. CONCLUSIONS: Older adults with bipolar disorder use the Internet much less frequently than younger adults. Many older adults do not use the Internet, and technology tools are suitable for some but not all older adults. As more health services are only available online, and more digital tools are developed, there is concern about growing health disparities based on age. Mental health experts should participate in determining the appropriate role for digital tools for older adults with bipolar disorder.

Comportamento social em ratos recuperados após desnutrição proteica: análise comparativa entre machos e fêmeas / Social behavior in rats recovered from protein malnutrition: comparative analysis between males and females

A maturação do sistema nervoso central depende, entre outros fatores, da ingestão adequada de nutrientes. Períodos de desnutrição podem afetar seu desenvolvimento, comprometendo a capacidade cognitiva. O objetivo do trabalho foi avaliar o comportamento social de ratos e ratas Wistar alimentados com dieta hipoproteica e posteriormente recuperados com dieta normoproteica. Foram utilizados ratos Wistar (machos e fêmeas) divididos em dois grupos: Controle (C), alimentado com dieta normoproteica (AIN 14% de proteína) durante 12 semanas e Recuperado (R), desnutrido com dieta hipoproteica (AIN 6% de proteína) por 6 semanas e posteriormente alimentado com dieta normoproteica da 7ª a 12ª semanas. A massa corporal foi verificada semanalmente e após o período experimental os animais foram submetidos aos testes de labirinto em cruz elevado e reconhecimento social. Foram avaliados os parâmetros sensoriais utilizados pelos ratos no reconhecimento de seus pares no lócus de convívio. Utilizou-se o paradigma intruso-residente na análise, sendo observado que a dieta hipoproteica comprometeu o ganho de massa corporal em machos e fêmeas, como também foi verificado redução na capacidade de reconhecer seus pares, após exposição consecutiva de curta duração, e ainda, houve uma intensa manifestação de agressividade nos machos do grupo recuperado, fato que não foi observado pelas fêmeas indicando que a intensidade de comprometimento no sistema nervoso central, gerado pela desnutrição pode ter relação com o dimorfismo sexual. (AU)

The maturation of the central nervous system depends, among other factors, proper intake of nutrients. Periods of malnutrition can affect your development, undermining the cognitive ability. The objective of this work was to evaluate the social behavior of mice and Wistar rats fed with hipoproteica diet and later recovered with present diet. Wistar rats were used (males and females) divided into two groups: control (C), fed up with the present diet (AIN 14% protein) for 12 weeks and recovered (R), malnourished with diet hipoproteica (AIN 6% protein) for 6 weeks and subsequently fed with the present diet of 7th to 12th weeks. Body mass was checked weekly and after the trial period the animals were subjected to the tests of high cross maze and social recognition. We evaluated the sensory parameters used by rats in the recognition of his peers in locus. The intruder-resident paradigm in the analysis, being observed that diet hipoproteica undertook the weight gain in males and females and verified reduction in ability to recognize their peers, after successive exposure of short duration, and yet, there was an intense manifestation of aggression in males of the group recovered, a fact that was not observed for females, indicating that the intensity of commitment in the central nervous system, generated by malnutrition may be related to sexual dimorphism. (AU)