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Transient receptor potential vanilloid 1 (TRPV1) is a calcium-permeable ion channel best known for its ability to be gated by the pungent constituent of red chili pepper, capsaicin, and related chemicals from the group of vanilloids as well as by noxious heat. As such, it is mostly expressed in sensory neurons to act as a detector of painful stimuli produced by pungent chemicals and high temperatures. Its activation is also sensitized by the numerous endogenous inflammatory mediators and second messengers, making it an important determinant of nociceptive signaling. Except for such signaling, though, neuronal TRPV1 activation may influence various organ functions by promoting the release of bioactive neuropeptides from sensory fiber innervation organs. However, TRPV1 is also found outside the sensory nervous system in which its activation and function is not that straightforward. Thus, TRPV1 expression is detected in skeletal muscle; in some types of smooth muscle; in epithelial and immune cells; and in adipocytes, where it can be activated by the combination of dietary vanilloids, endovanilloids, and pro-inflammatory factors while the intracellular calcium signaling that this initiates can regulate processes as diverse as muscle constriction, cell differentiation, and carcinogenesis. The purpose of the present review is to provide a clear-cut distinction between neurogenic TRPV1 effects in various tissues consequent to its activation in sensory nerve endings and non-neurogenic TRPV1 effects due to its expression in cell types other than sensory neurons.

Little is known about how mitotic cells round against epithelial confinement. At the beginning of mitosis, cells markedly change their morphology as they round up1. During mitotic cell rounding, the microtubule cytoskeleton forms the mitotic spindle, a central machinery that captures and organizes chromosomes2. Mitotic cell rounding occurs in the vast majority of animal cells3 and plays a role in maintaining tissue organization. Here, we have engineered micropillar arrays with spatial and mechanical properties to mimic the mechanical confinement of epithelia and to measure the forces generated by single epithelial cells rounding for mitosis. For our studies we use Madin?Darby canine kidney (MDCK) cell lines that are commonly used as a model for epithelial cells. We observe that MDCK cells deflect nearby micropillars as they round and thereby create sufficient space for mitosis.However, if mitotic cells cannot create sufficient space, their rounding force, which is generated by actomyosin contraction and hydrostatic pressure, pushes the cell out of confinement. After conducting mitosis in an unperturbed manner, both daughter cells return to the confinement of the pillars. Cells that cannot round against nor escape confinement cannot orient their mitotic spindles and more likely undergo apoptosis. The results highlight how spatially constrained epithelial cells prepare for mitosis: either they are strong enough to round up or they must escape. The ability to escape from confinement and reintegrate after mitosis appears to be a basic property of epithelial cells4,5. The availability of large pillar arrays and the optical readout of the assay enables the simultaneous characterization of hundreds of single cells to investigate the cellular mechanisms that drive the drastic shape change in mitosis.We have demonstrated that the contributions of proteins involved in mitotic cell rounding to generating force can be quantified by combining the micropillar assay with targeted chemical perturbation. Thus, the micropillar assay opens up the possibility to perform a large-scale screen for genes and mechanisms involved in mitotic cell rounding.References:1. McConnell, C. H. Mitosis in hydra - mitosis in the ectodermal epitheliomuscular cells of Hydra. Biol. Bull. 64, 86?95 (1933).2. Cramer, L. P. & Mitchison, T. J. Investigation of the mechanism of retraction of the cell margin and rearward flow of nodules during mitotic cell rounding. Mol. Biol. Cell 8, 109?119 (1997).3. Kline-Smith, S. L. & Walczak, C. E. Mitotic spindle assembly and chromosome segregation: refocusing on microtubule dynamics. Mol. Cell 15, 317?327 (2004).4. Stewart, M. P. et al. Hydrostatic pressure and the actomyosin cortex drive mitotic cell rounding. Nature 469, 226?230 (2011).5. Sorce, B. et al. Mitotic cells contract actomyosin cortex and generate pressure to round against or escape epithelial confinement. Nature Commun. 25, 8872-8876 (2015)

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. Many wild plants of the Cerrado bioma are used as medicinal plants. The pequi (Caryocar brasiliensis) is representative of those equipped with molluscicidal action against schistosomiasis. This paper sets out to verify the toxic action of pequi fractions in other aquatic animals before they are used in rivers or lakes. Analysis were made of the alterations to the mitotic index of epithelia cells in the gills of guppy (Poecilia vivipara) exposed to ethyl-acetate fraction of leaf pequi and bark. Animals exposed to ethyl-acetate fraction (leaf), no significant change was observed in the mitotic index when compared with the control group, whereas in fish exposed to ethyl-acetate fraction (bark) we detected an increase in mitotic index of the epithelia cells in two regions of the branchial filaments. Thus, ethyl-acetate fractions (leaf) could be used against schistosomiasis, given their high efficacy and low action as piscicide.

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. Many wild plants of the Cerrado bioma are used as medicinal plants. The pequi (Caryocar brasiliensis) is representative of those equipped with molluscicidal action against schistosomiasis. This paper sets out to verify the toxic action of pequi fractions in other aquatic animals before they are used in rivers or lakes. Analysis were made of the alterations to the mitotic index of epithelia cells in the gills of guppy (Poecilia vivipara) exposed to ethyl-acetate fraction of leaf pequi and bark. Animals exposed to ethyl-acetate fraction (leaf), no significant change was observed in the mitotic index when compared with the control group, whereas in fish exposed to ethyl-acetate fraction (bark) we detected an increase in mitotic index of the epithelia cells in two regions of the branchial filaments. Thus, ethyl-acetate fractions (leaf) could be used against schistosomiasis, given their high efficacy and low action as piscicide.