Repetitive exposure of the skin to UV radiation induces various harmful changes, such as thickening, wrinkle formation, inflammation and carcinogenesis. A variety of natural compounds and synthetic compounds have been studied to determine whether they can prevent UV-induced harmful effects. In this study, we investigated the effect of a novel compound, Melanocin A, which was isolated from Eupen...

In order to provide a quantitative basis for pretreatment and therapy of intoxications with sulfur mustard (SM) the toxicokinetics of this agent as well as its major DNA-adduct were studied in male hairless guinea pigs for the intravenous, respiratory and percutaneous routes. The study comprised measurement of the concentration-time course of SM in blood and measurement of the concentrations of...

Ultrasonic mid-air haptic technologies, which provide feedback through airwaves produced using ultrasound, could be employed to investigate the sense of body ownership and immersion in virtual reality (VR) by inducing hand illusion (VHI). perception has solely been investigated for glabrous (hairless) skin, higher tactile sensitivity than hairy skin. In contrast, VHI paradigm typically targets ...

Oral supplementation with collagen hydrolysate (CH) has been shown to improve the condition of the skin in humans and experimental animals. Several hydroxyproline-containing oligo-peptides were previously detected in human peripheral blood after the ingestion of CH, and the two dipeptides, prolyl-hydroxyproline (PO) and hydroxyprolyl-glycine (OG), have been proposed to have beneficial effects o...

In our previous study, N-phenethyl caffeamide (K36) was proved to act as an antioxidant and an antiphotoaging agent by inhibiting type I procollagen degradation and stimulating collagen synthesis in human skin fibroblasts. In the present study, in vitro and in vivo experiments were conducted to investigate the mechanism of action and the antiinflammatory and antiphotoaging activity of K36. K36 ...

We use a mutant hairless Sprague Dawley rat to evaluate the capacity of retinoids to inhibit the epidermal ornithine decarboxylase activity induced by sellotape stripping. In order to minimize the variability introduced by the animals in our model we decided to validate the hairless rats used. A number of animal parameters were examined using a single lot of 50 males and 50 females aged from 4 ...

The renin-angiotensin system is known to be involved in skin remodeling and inflammation. Previously, we reported that ultraviolet B (UVB) irradiation enhanced angiotensin-converting enzyme (ACE) expression and angiotensin II levels in hairless mouse skin, and an ACE inhibitor, enalapril maleate (EM), accelerated repair of UVB-induced wrinkles. In this study, we analyzed gene expression profile...

Oral ingestion of collagen peptides (CP) has long been suggested to exert beneficial effects on the skin, but the molecular events induced by CP on the skin remain unclear. Here, we investigated the effects of oral CP administration on gene expression in hairless mouse skin and of prolyl-hydroxyproline (Pro-Hyp), a collagen-derived dipeptide, on gene expression in a coculture of mouse skin kera...

The aim of this study was to determine transport of lidocaine ions through a hairless rat skin in vivo and to compare the efficacy of alternating current (AC) with that of direct current (DC) iontophoresis (IOP). We measured the concentration of lidocaine transported through a cellophane membrane or a hairless rat dorsal skin applying either AC-IOP or DC-IOP. The results revealed that lidocaine...

The extent of uptake of gamma interferon (gamma-IFN) in various strata of hairless mouse, human and hamster skin upon application of a liposomal formulation and an aqueous solution were determined by in vitro diffusion cell experiments. For each of the animal species studied, 70-80% of the liposomally entrapped IFN was deposited onto or penetrated into the skin as determined 24 h after in vitro...