Increase in neuropilin-1 on the surface of growth cones and putative raft domains in neuronal NG108-15 cells co-cultured with vascular smooth muscle SM-3 cells.

The mechanisms underlying autonomic innervation to its targets involve various chemical factors, but have not yet been elucidated in detail. We constructed a co-culture system of neuronal cells and vascular smooth muscle cells to investigate the mechanisms underlying innervation of the vasculature. A co-culture with the vascular smooth muscle cell line, SM-3 significantly promoted cell viability, neurite extension, and neuropilin-1 (Nrp-1) mRNA expression in the cholinergic neuronal cell line, NG108-15. Furthermore, immunocytochemistry with or without a detergent treatment revealed that a co-culture with SM-3 cells or culturing with the conditioned medium of SM-3 cells translocated Nrp-1 onto the cell surface of growth cones rather than varicosities of NG108-15 cells. Immunofluorescent microscopy combined with a cold detergent treatment or cholesterol depletion revealed that Nrp-1 accumulated in putative raft domains in the plasma membrane of NG108-15 cells co-cultured with SM-3 cells. The results of the present study suggest that some soluble factors from smooth muscle cells may affect the localization of Nrp-1 in cholinergic neuronal cells, which may, in turn, be involved in the autonomic innervation of blood vessels.

Butane-2,3-dione: the key contributor to axillary and foot odor associated with an acidic note.

Human body odor, which contains several volatile organic compounds, possesses various odor qualities. To identify key volatile compounds responsible for the common unpleasant odors derived from human axillae and feet, the odor quality and intensity of 118 human axillae and feet were directly evaluated by sniffing, and odor compounds obtained from the subjects were identified. Furthermore, the sensory differences in odor intensity and quality with and without addition of butane-2,3-dione were evaluated by using the visual analog scale (VAS). An acidic odor was a common unpleasant note in human axillae and feet. Butane-2,3-dione was identified as a key compound associated with this odor. Strong positive correlations between the amount of butane-2,3-dione, and the odor intensities of axillae and feet were observed, and the addition of butane-2,3-dione solution to blended short-chain fatty-acid solutions caused significantly increased VAS values of axillary-like odor, unpleasantness, and odor intensity compared to those of each solution without added butane-2,3-dione.

Activated carbon/titanium dioxide composite to adsorb volatile organic compounds associated with human body odor.

The human body generates various malodor compounds in different body parts and even in the same parts. A more effective and versatile deodorant material that can suppress various key contributors to the body odor must be developed to improve the quality of life of affected individuals. In this study, activated carbon (AC) was found to have higher adsorption ability toward key body odor-generating compounds than zinc oxide (ZnO), which is a well-known deodorant material. To prevent pigmentation of human skin induced by the direct application of AC, white activated carbon (WAC) was developed by blending AC, titanium dioxide (TiO2), and ammonium acrylate copolymer. AC to TiO2 ratio of 1:6 was found to be the optimum blending ratio to form WAC. Compared with ZnO, this optimal WAC exhibited higher adsorption ability toward five key body odor compounds. The in vivo evaluation of the sample containing WAC revealed that it significantly suppressed the generation of axillary odor without a bactericidal effect. The developed WAC can effectively suppress the human body odor in different body parts. These findings are valuable for individuals experiencing psychological stress attributed to their unpleasant body odor.