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Purpose: To investigate the effects of neonatal malnutrition followed by nutritional replacement on the signaling mechanisms developed by the inflammasome complex by analyzing the expression of the targeted TLR2, TLR4, NLRP3, caspase-1 and release of IL-1β and IL-18 by alveolar macrophages infected in vitro with Candida albicans., Methods: Male Wistar rats (n = 24), 90-120 days, were suckled by mothers whose diet during lactation contained 17 % protein in the nourish group and 8 % protein in the malnourished group. After weaning, both groups were fed a normal protein diet. Macrophages were obtained after tracheostomy, through the collection of bronchoalveolar lavage fluid. The quantification of the expression levels of targets (TLR2, TLR4, NLRP3 and caspase-1) was performed by real-time RT-PCR. Production of cytokines was performed by ELISA., Results: The malnourished animals during lactation showed reduced body weight from the fifth day of life, remaining until adulthood. Further, the model applied malnutrition induced a lower expression of TLR4 and caspase-1. The quantification of the TLR2 and NLRP3, as well as the release of IL-1β and IL-18, was not different between groups of animals nourished and malnourished. The system challenged with Candida albicans showed high expression levels of all targets in the study., Conclusions: The tests demonstrate nutritional restriction during critical periods of development, although nutritional supplementation may compromise defense patterns in adulthood in a timely manner, preserving distinct signaling mechanism, so that the individual does not become widely vulnerable to infections by opportunistic pathogens.

We examine fluctuations in particle density in the restricted-height, conserved stochastic sandpile (CSS). In this and related models, the global particle density is a temperaturelike control parameter. Thus local fluctuations in this density correspond to disorder; if this disorder is a relevant perturbation of directed percolation (DP), then the CSS should exhibit non-DP critical behavior. We analyze the scaling of the variance Vℓ of the number of particles in regions of ℓd sites in extensive simulations of the quasistationary state in one and two dimensions. Our results, combined with a Harris-like argument for the relevance of particle-density fluctuations, strongly suggest that conserved stochastic sandpiles belong to a universality class distinct from that of DP.

Plants of Crotalaria genus (Leguminosae) present large amounts of the pyrrolizidine alkaloid monocrotaline (MCT) and cause intoxication to animals and humans. Therefore, we investigated the MCT-induced cytotoxicity, morphological changes, and oxidative and genotoxic damages to glial cells, using the human glioblastoma cell line GL-15 as a model. The comet test showed that 24h exposure to 1-500microM MCT and 500microM dehydromonocrotaline (DHMC) caused significant increases in cell DNA damage index, which reached 42-64% and 53%, respectively. Cells exposed to 100-500microM MCT also featured a contracted cytoplasm presenting thin cellular processes and vimentin destabilisation. Conversely, exposure of GL-15 cells to low concentrations of MCT (1-10microM) clearly induced megalocytosis. Moreover, MCT also induced down regulation of MAPs, especially at the lower concentrations adopted (1-10microM). Apoptosis was also evidenced in cells treated with 100-500microM MCT, and a later cytotoxicity was only observed after 6 days of exposure to 500microM MCT. The data obtained provide support for heterogenic and multipotential effects of MCT on GL-15 cells, either interfering on cell growth and cytoskeletal protein expression, or inducing DNA damage and apoptosis and suggest that the response of glial cells to this alkaloid might be related to the neurological signs observed after Crotalaria intoxication.

Dehydromonocrotaline (DHMC) is the main monocrotaline active cytochrome P450's metabolite, and has already been assessed in the CNS of experimentally intoxicated rats. DHMC effects were here investigated toward rat astroglial primary cultures regarding cytotoxicity, morphological changes and regulation of GFAP expression. Cells, grown in DMEM supplemented medium, were treated with 0.1-500 microM DHMC, during 24- and 72-h. According to MTT and LDH tests, DHMC was toxic to astrocytes after 24-h exposure at 1 microM, and induced membrane damages at 500 microM. Rosenfeld dying showed hypertrophic astrocytes after 72-h exposure to 0.1-1 microM DHMC. GFAP immunocytochemistry and western immunoblot revealed an increase of GFAP labelling and expression, suggesting an astrogliotic reaction to low concentrations of DHMC. At higher concentrations (10-500 microM), astrocytes shrank their bodies and retracted their processes, presenting a more polygonal phenotype and a weaker expression on GFAP labelling Nuclear chromatin staining by Hoechst-33258 dye, revealed condensed and fragmented chromatin in an important proportion (+/-30%) of the astrocytes exposed to 100-500 microM DHMC, suggesting signs of apoptosis. Our results confirm a cytotoxic and dose-dependent effect of DHMC on cultures of rat cortical astrocytes, leading to apoptotic figures. These effects might be related to the neurological damages and clinical signs observed in animals intoxicated by Crotalaria.