Glucomannan Dotaz Zobrazit nápovědu
Glucomannans belong to yeast and fungal cell wall polysaccharides with known immunostimulatory and radioprotective effects. However, glucomannan protective effects against pathological consequences of skin exposure to short wavelength solar light, ultraviolet (UV) radiation, are unclear. Herein, a highly branched glucomannan (GM) isolated from the cell wall of Candida utilis, a member of the alpha-(1-->6)-D-mannan group, was tested for its photoprotective effects in an in vitro model of UVB-irradiated human keratinocytes and an in vivo model of UV-induced erythema formation in human volunteers. GM suppressed the UVB-induced decrease of keratinocyte viability, which was connected with the suppression of UVB-induced keratinocyte apoptosis. GM reduced UVB-mediated caspase activation together with suppression of DNA fragment release into the cytoplasm. Furthermore, GM suppressed UVB-induced gene expression of pro-inflammatory markers including nuclear factor kappa B, inducible nitric oxide synthase, interleukins 8 and 1, together with suppression of prostaglandin E2 and interleukin 1alpha protein release. In vivo, GM decreased UV-induced skin erythema formation, which was correlated with a decrease of phosholipase A(2) activity within the stratum corneum. It could be concluded that GM isolated from C. utilis possesses significant photoprotective effects on human keratinocytes in vitro as well as in vivo.
- MeSH
- apoptóza účinky léků účinky záření MeSH
- biologické markery analýza MeSH
- Candida chemie MeSH
- erytém etiologie prevence a kontrola MeSH
- exprese genu MeSH
- financování organizované MeSH
- hodnocení léčiv MeSH
- keratinocyty účinky léků účinky záření MeSH
- kultivované buňky MeSH
- lidé MeSH
- mannany aplikace a dávkování farmakologie izolace a purifikace MeSH
- radioprotektivní látky aplikace a dávkování farmakologie MeSH
- ultrafialové záření škodlivé účinky MeSH
- viabilita buněk účinky léků MeSH
- zánět MeSH
- Check Tag
- lidé MeSH
It is well documented that the polysaccharide glucomannan (GM), an abundant constituent of the fungal cell wall, in the form of particulate induces strong activation of phagocytes, however, the effects of soluble GM are not known. Activation of phagocyte anti-microbial mechanisms is a crucial part of the innate host defense against invading pathogens. However, under uncontrolled inflammatory conditions they contribute to damage of surrounding tissues. Thus, to prevent these deleterious effects, the activation of phagocytes is a tightly regulated process. Therefore, in this study we analyzed the effect of soluble GM on some neutrophil functions such as reactive oxygen species production, degranulation, and receptor mobilization at the plasma membrane. Soluble GM at the tested concentrations did not stimulate oxidative burst of phagocytes directly but significantly potentiated oxidative burst in response to opsonized zymosan particles. GM induced significant phosphorylation of p47phox subunit of NADPH oxidase on Ser345. This priming effect of GM was accompanied by time and concentration dependent degranulation characterized by increased surface expression of receptors stored in neutrophil granules (CD10, CD11b, CD14, CD35, and CD66b). Degranulation was further confirmed by increase of elastase activity in media. Thus, it could be suggested that soluble GM induces priming of phagocytes connected with their degranulation, the increase of surface receptor expression, and potentiation of oxidative burst response to opsonized particles through the activation of NADPH oxidase.
- MeSH
- Candida chemie MeSH
- fagocyty metabolismus účinky léků MeSH
- fosforylace účinky léků MeSH
- lidé MeSH
- mannany farmakologie MeSH
- NADPH-oxidasy metabolismus MeSH
- rac proteiny vázající GTP metabolismus MeSH
- respirační vzplanutí účinky léků MeSH
- zymosan farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- MeSH
- antigeny CD11b MeSH
- biologické jevy * MeSH
- Candida izolace a purifikace MeSH
- fagocyty * fyziologie MeSH
- keratinocyty imunologie MeSH
- lidé MeSH
- mannany * imunologie MeSH
- mediátory zánětu MeSH
- ochranné látky MeSH
- přípravky chránící proti slunci MeSH
- purgativa MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
