Impact of Trans-Fats on Heat-Shock Protein Expression and the Gut Microbiota Profile of Mice.

Partially hydrogenated oils are known to cause metabolic stress and dyslipidemia. This paper explores a new dimension about the interaction between dietary trans-fats and the defense heat-shock protein (HSP) system, inflammation, and the gut microbiota of mice consuming a hyperlipidic diet containing partially hydrogenated vegetable oil free of animal fat. Five diet groups were installed: control diet, 2 hyperlipidic-partially hydrogenated-oil diets, each containing either casein or whey-protein hydrolysate (WPH) as protein source, and 2 consuming hyperlipidic-unhydrogenated-oil diets containing either WPH or casein as a protein source. The partially hydrogenated oil inhibited c-Jun NH2 -terminal kinase phosphorylation in the casein diets, but without altering κ-B kinase. Neither the lipid nor the protein had an influence on the proinflammatory toll-like receptor 4 (TLR4) pathway, but the combination of the high-lipid content and WPH impaired glucose tolerance without altering insulin or glucose transporter-4 translocation. It was remarkable to observe that, contrary to the case of a common high-fat diet, the lard-free hyperlipidic diets were hardly able to invert the Bacteroidetes:Firmicutes phylum ratio. Our results suggest that, in the absence of lard, the intake of trans-fatty acids is less harmful than expected because it does not trigger TLR4-inflammation or pose great threat to the normal gut microbiota. WPH had the effect of promoting the expression of HSP90, HSP60, and HSP25, but did not prevent dysbiosis, when the diet contained the unhydrogenated oil. The partially hydrogenated oil also seemed to antagonize the ability of WPH to induce the expression of protective HSPs.

Fructooligosaccharide intake promotes epigenetic changes in the intestinal mucosa in growing and ageing rats.

PURPOSE: The aim of this study was to investigate the relationship between fructooligosaccharide (FOS) intake at different life stages of Wistar rats and its stimulatory effects on intestinal parameters. METHODS: Recently weaned and ageing female rats were divided into growing and ageing treatments, which were fed diets that partially replaced sucrose with FOS for 12 weeks. RESULTS: Dietary FOS intake induced a significant increase in the numbers of Bifidobacterium and Lactobacillus in growing rats. FOS intake was associated with increased butyric acid levels and a reduced pH of the caecal contents at both ages. Differential gene expression patterns were observed by microarray analysis of growing and ageing animals fed the FOS diet. A total of 133 genes showed detectable changes in expression in the growing rats, while there were only 19 gene expression changes in ageing rats fed with FOS. CONCLUSION: These results suggest that dietary FOS intake may be beneficial for some parameters of intestinal health in growing rats.

Proteomic and histopathological response in the gills of Poecilia reticulata exposed to glyphosate-based herbicide.

Glyphosate-based herbicides (GBH) are one of the most used herbicide nowadays, whilst there is growing concern over their impact on aquatic environment. Since data about the early proteomic response and toxic mechanisms of GBH in fish is very limited, the aim of this study was to investigate the early toxicity of GBH in the gills of guppies Poecilia reticulata using a proteomic approach associated with histopathological index. Median lethal concentration (LC50,96 h) was determined and LC50,96h values of guppies exposed to GBH were 3.6 ± 0.4 mg GLIL(-1). Using two-dimensional gel electrophoresis associated with mass spectrometry, 14 proteins regulated by GBH were identified, which are involved in different cell processes, as energy metabolism, regulation and maintenance of cytoskeleton, nucleic acid metabolism and stress response. Guppies exposed to GBH at 1.82 mg GLIL(-1) showed time-dependent histopathological response in different epithelial and muscle cell types. The histopathological indexes indicate that GBH cause regressive, vascular and progressive disorders in the gills of guppies. This study helped to unravel the molecular and tissue mechanisms associated with GBH toxicity, which are potential biomarkers for biomonitoring water pollution by herbicides.

Anti-inflammatory activity of Ocimum americanum L. essential oil in experimental model of zymosan-induced arthritis.

Essential oils are potential sources of novel components for medicinal use. The present study was performed to investigate the composition and anti-inflammatory activity of Ocimum americanum L. essential oil (OEO) and its components in an experimental model of zymosan-induced arthritis and paw edema. The essential oil was obtained by hydro-distillation and analyzed by gas chromatography-mass spectrometry. Twenty-six components, representing 98.9% of the total oil, were characterized, with linalool (19.63%) and 1,8-cineole (17.27%) as the main components. The OEO and its two constituents inhibited leukocyte influx into the synovial space and reduced paw edema induced by zymosan. The OEO also inhibited interferon-γ levels but did not reduce transforming growth factor-ß levels. Additionally, the OEO protected against leukocyte influx into the synovial membrane and cartilage destruction in knee joints in arthritic mice. These findings indicate that the essential oil of Ocimum americanum L. exerted significant anti-inflammatory effects, likely related to its main compounds.

Phenotypical and functional analysis of intraepithelial lymphocytes from small intestine of mice in oral tolerance.

In this work, we evaluated the effects of administration of OVA on phenotype and function of intraepithelial lymphocytes (IELs) from small intestine of transgenic (TGN) DO11.10 and wild-type BALB/c mice. While the small intestines from BALB/c presented a well preserved structure, those from TGN showed an inflamed aspect. The ingestion of OVA induced a reduction in the number of IELs in small intestines of TGN, but it did not change the frequencies of CD8(+) and CD4(+) T-cell subsets. Administration of OVA via oral + ip increased the frequency of CD103(+) cells in CD4(+) T-cell subset in IELs of both BALB/c and TGN mice and elevated its expression in CD8ß(+) T-cell subset in IELs of TGN. The frequency of Foxp3(+) cells increased in all subsets in IELs of BALB/c treated with OVA; in IELs of TGN, it increased only in CD25(+) subset. IELs from BALB/c tolerant mice had lower expression of all cytokines studied, whereas those from TGN showed high expression of inflammatory cytokines, especially of IFN-γ, TGF-ß, and TNF-α. Overall, our results suggest that the inability of TGN to become tolerant may be related to disorganization and altered proportions of inflammatory/regulatory T cells in its intestinal mucosa.

Adaptation of the gill epithelium of an euryhaline fish, the guppy (Poecilia vivipara), to freshwater / Adaptação do epitélio branquial de peixes eurialinos, guaru (Poecilia vivipara), para água doce

The south-american euryhaline fish Poecilia vivipara (BLOCH; SNEIDER, 1801), the guppy, is found both in estuary and river waters, which suggests high adaptability to environments of different salinity. In this work we studied the adaptation of the interlamellar, bars and rakers epithelia of the gills of estuary fish to freshwater conditions. The results reveal that the gill epithelia of Poecilia vivipara can adjust itself to freshwater by decreasing the VP of mucous cells of the interlamellar epithelium and increase the volumetric proportion (VP) of chloride cells. However, there was no evidence of similar morphological alteration in the rakers region. The epithelia of the rakers appears to be part of a different compartment that is less sensitive to variation of salinity.

O peixe eurihalino sul-americano Poecilia vivipara (BLOCH; SNEIDER, 1801), o guppy, é encontrado tanto em estuários quanto em águas de rios, o que sugere uma alta adaptabilidade aos diferentes ambientes de salinidade. Neste trabalho, estudamos a adaptação do epitélio interlamelar, do arco e do rastelo das brânquias dos peixes de estuário de água doce. Os resultados revelam que o epitélio branquial de Poecilia vivipara pode ajustar-se à água doce, diminuindo a proporção volumétrica (PV) de células mucosas do epitélio interlamelar e aumentando a PV de células clorídricas. No entanto, não houve nenhuma evidência de alteração morfológica semelhante na região do rastelo branquial. O epitélio do rastelo branquial parece ser parte de um compartimento diferente que é menos sensível a variações de salinidade.

Immunocytochemical studies of adhesion molecules on mouse UNK cells and their extracellular matrix ligands during mouse pregnancy.

Uterine natural killer (uNK) cells are the dominant lymphocytes of pregnant mammals' uterus. Studies have identified four differentiation stage of mouse uNK cells based on Dolichos biflorus lectin cytochemistry, and their distribution showed preferential domain in the uterus through out the pregnancy. This work was done to investigate the expression of alpha5, alpha6, and beta7 integrins on uNK cells and their ligands distribution. Section of mouse uterus from sixth to seventeenth gestational days were submitted to immunocytochemistry and positive reactions for alpha5, alpha6, and beta7 integrins were found on uNK from eighth to tenth gestational days but not after twelfth gestational days. Fibronectin reactions were seemed from sixth to tenth gestational days around uNK from the myometrium and endometrium close to the myometrium. No reaction for fibronectin was seen in the decidualized and nondecidualized endometrium near the placenta. Laminin reaction was seen just in the antimesometrial side. beta7 integrin seems to be the active receptor to bind with VCAM-1 or MAdCAM-1 of endothelial cells, promoting the uNK cross through the vessels. The absence of laminin in an uNK domain suggests these cells are not dependent of laminin and alpha6 integrin for their establishment. However, fibronectin seems to support uNK migration, proliferation, differentiation, and survival in the uterus by binding with alpha5 integrin. The loss of alpha5 integrin ligation by the down regulation of fibronectin could inhibits these events and further studies are need to investigate whether unligated alpha5 can actively and initiate apoptosis, maybe in a caspase 8-dependent way that has been called integrin-mediated death.

Relaxation of the mouse pubic symphysis during late pregnancy is not accompanied by the influx of granulocytes.

In some animals, such as mice and guinea pigs, a hormonally controlled mechanism increases the flexibility of the pubic symphysis and enhances the cervical remodeling necessary for safe delivery. Cervical ripening during pregnancy is associated with a paradoxical influx of leukocytes. However, the changes in cell metabolism during relaxation of the mouse pubic symphysis for delivery have not been extensively studied. In this work, we used light microscopy and transmission and scanning electron microcopy, as well as immunohistochemistry and Western blotting for MMP-8, to investigate the involvement of granulocytes or resident stromal cells in the relaxation of the virgin pubic symphysis during late pregnancy (days 18 and 19, before delivery) in vivo and in explanted joints. MMP-8 was studied because this collagenase is a hallmark for cervical ripening associated with the influx of granulocytes during late pregnancy. Extensive dissolution and disorganization of the extracellular matrix was seen around fibroblastic-like cells in late pregnancy. In contrast to the cervix (positive control), morphological and immunohistochemical analyses revealed that there was no characteristic cellular inflammatory response in the interpubic tissue. Staining for MMP-8 was observed in chondroid and fibroblastic-like cells of virgin and relaxed interpubic ligament, respectively. However, no granulocytes were seen during the extensive remodeling of the pubic joint in late pregnancy. These results indicate that constitutive stromal cells may have an important role in tissue relaxation during remodeling of the pubic symphysis in pregnancy.

Índice mitótico em células epiteliais da brânquia de Guaru (Poecilia vivipara) tratados com frações da casca do caule e da folha de pequi (Caryocar brasiliensis) / Mitotic index of epithelia cells in gills of Guppy (Poecilia vivipara) exposed to fractions of the leaf and bark of pequi (Caryocar brasiliensis)

Várias plantas nativas do bioma Cerrado são utilizadas como plantas medicinais. Dentre elas, o pequi possuí ação moluscicida utilizada no combate a esquistossomose. Objetivamos neste trabalho a verificação da toxicidade de frações de pequi sobre outros organismos aquáticos, antes da utilização destas em mananciais. Para isso, analisamos alterações no índice mitótico das células epiteliais das brânquias de Guaru (Poecilia vivipara) expostas às frações da folha e da casca do caule de pequi extraídas com acetato de etila. Constatamos que nenhuma das frações se mostrou letal aos peixes. Os animais expostos à fração acetato de etila da folha não apresentaram modificações significativas no índice mitótico em relação ao grupo controle, mas os animais expostos à fração acetato de etila da casca do caule apresentaram aumento do índice mitótico das células epiteliais em duas regiões dos filamentos branquiais. Desta forma, a fração acetato de etila da folha poderia ser utilizada como moluscicida em mananciais, enquanto que a fração acetato de etila da casca do caule necessitaria passar por outros testes mais específicos.

Efeitos do fluoreto de sódio no epitélio da brânquia do peixe Guaru (Poecilia vivipara) / Effects of sodium fluoride in gill epithelium of Guppy fish (Poecilia vivipara)

O flúor é muito utilizado pelo homem e facilmente encontrado na natureza. Por isso, vários estudos foram realizados visando a toxicidade e o seu efeito cumulativo nos tecidos animais. É descrito que o fluoreto de sódio pode ser empregado no controle do hospedeiro da esquistossomose (Biomphalaria glabrata). Visando a preservação do meio aquático, propõe-se a verificação do efeito do fluoreto de sódio em peixes (Poecilia vivipara). Dez peixes foram submetidos à água declorinada (GC) e o restante foi submetido à água contendo fluoreto de sódio na concentração de 5 ppm (GE), por vinte e um dias. Após esse período, os animais foram sacrificados e suas brânquias foram retiradas. As brânquias foram fixadas, pós-fixadas e desidratadas de acordo com o protocolo das técnicas de histoquímica e análise ultra-estrutural, respectivamente. As peças foram diafanizadas em xilol. Para observação histológica das células mucosas e células do cloro, foi utilizada a técnica de coloração de Hematoxilina + eosina. E para a detecção histoquímica de glicoconjugados utilizou-se as técnicas de P.A.S., P.A.S + amilase salivar, P.A.S. + acetilação, P.A.S. + acetilação reversível, alcian Blue (AB) pH 2,5 + metilação, AB pH 2,5 + metilação reversível, AB pH 2,5 e AB pH 0,5. Observou-se aumento na secreção de muco e na quantidade de células mucosas do epitélio branquial, além de diferenças na reatividade histoquímica das células mucosas do GE comparados ao GC, sugerindo uma resposta adaptativa desses animais ao novo ambiente.

Differential distribution of elastic system fibers in the pubic symphysis of mice during prefnancy, partum and post-partum

The expansion of the pubic symphysis during pregnancy in some rodet depends on the growth of the interpubic ligament, primarily through the biosynthesis of extracellular matrix. Although there is a significant metabolism of elastin in the female reproductive tract during pregnancy, little is known of the architectural and ultrastructural aspects of the elastic system fibers in the mouse pubic symphysis. In this study, the main characteristics of the elastic system of the mouse pubic symphysis during pregnancy, partum and post-partum were determined by light and electron microscopy. A distinct arrangement of microfibrils, elastin deposition and development of the extracellular matrix formed a supporting framework that uniformly distributed stress in order to provide adequate interpubic resilience during delivery. These changes support a role for elastic system fibers in symphyseal maturation and reconstruction during pregnancy and after delivery.