ABSTRACT
PURPOSE: Skin pH, an indicator of skin health, is maintained by various organic factors, which include lactate, free amino acid (FAA), and free fatty acid (FFA). As skin ages or with illness, skin pH becomes less acidic, and functional food has been developed to maintain the acidic pH of skin. In this study, we determined the dietary effect of green tea extract (GTE) on skin pH of photo-aged mice, as measured by epidermal levels of lactate, FAA, and FFA. The protein expression and activity of lactate dehydrogenase (LDH), an enzyme of pyruvate reduction for lactate generation, was further determined. METHODS: Albino hairless mice were fed a control diet (group UV+) or a diet with 1% GTE (group GTE) in parallel with UV irradiation for 10 weeks. A normal control group was fed a control diet without UV irradiation for 10 weeks (group UV-). RESULTS: Skin pH was higher (less acidic) in group UV+ than in group UV-. In parallel, epidermal levels of lactate and FFA, as well as of LDH protein expression and activity, were reduced in group UV+. Dietary supplementation of GTE (group GTE) reduced skin pH to similar to the level of group UV-, and inversely increased epidermal levels of lactate, LDH protein expression and activity, but not of FFA. Although epidermal levels of FAA were similar in groups UV- and UV+, it was increased in group GTE to a level higher than in group UV-. In further analysis of major FFA, epidermal levels of palmitic acid [16:0], oleic acid [18:1(n-9)], and linoleic acid [18:2(n-6), but not of stearic acid [18:0] in group GTE were similar to or lower than those in group UV+. CONCLUSION: Dietary GTE normalized skin pH with increased levels of lactate and FAA, as well as with increased protein expression and activity of LDH in the epidermis of UVB irradiated hairless mice.
Subject(s)
Animals , Mice , Diet , Dietary Supplements , Epidermis , Functional Food , Hydrogen-Ion Concentration , L-Lactate Dehydrogenase , Lactic Acid , Linoleic Acid , Mice, Hairless , Oleic Acid , Palmitic Acid , Pyruvic Acid , Skin , TeaABSTRACT
In this study, we evaluate a method for the early diagnosis of radiodermatitis for use in the prevention and therapy of this condition. Hairless mice (SKH1-hr) were used to study the early diagnosis of radiodermatitis. Lactate dehydrogenase (LDH, EC 1.1.1.27) isozymes were analyzed using native-polyacrylamide gel electrophoresis and western blotting of blood serum and tissues collected from SKH1-hr mice. Radiodermatitis developed 24 days after the first X-irradiation. Reduced spleen weight was observed after the last X-irradiation (P<0.05). Thereafter the weight increased until 24 days after the first irradiation, finally reaching levels comparable to those in the sham-irradiated control group. LDH activity was the highest in skeletal muscle and lowest in blood serum. LDH C4, A4, A3B, A2B2, AB3, and B4 isozymes were detected, in the mentioned order, from the cathode. This result was similar in other mouse strains. In the irradiated group, LDH A4 isozyme levels were reduced in the serum until inflammation occurred, whereas those of B4 isozyme were elevated. The subunits A and B followed a similar trend to that of LDH A4 and B4 isozyme, respectively. Importantly, antibodies against LDH B4 isozyme could prove useful in the early diagnosis of radiodermatitis.
Subject(s)
Animals , Mice , Antibodies , Blotting, Western , Early Diagnosis , Electrodes , Electrophoresis , Inflammation , Isoenzymes , L-Lactate Dehydrogenase , Lactic Acid , Mice, Hairless , Muscle, Skeletal , Radiodermatitis , Serum , SpleenABSTRACT
The purpose of this study was to compare the skin changes in female SKH-1 hairless mice between UVB irradiated photo-aged group and endogenous aged group. The UVB irradiation and endogenous aged groups showed poor skin conditions when compared with normal (N) group in terms of the skin erythema, water content and TEWL (transepidermal water loss). For the changes in gross observation and replica image analysis on wrinkle of the skin tissue, UVB irradiation group showed thicker, wider and deeper wrinkles than the changes seen in N group, whereas endogenous aged group showed thinner, narrower and shallower wrinkles than that of UVB irradiation group. In histopathological findings, UVB irradiation group and endogenous aged group showed thickened epidermis, increased dermal inflammatory cells, decreased collagen and elastic fiber content, increased number of degranulated dermal/subcutaneous mast cells, and lower expression quantity of TGF-beta in dermal layer when compared with N group, but to a lesser extent in aged group than the changes in UVB irradiation group. UVB irradiation group and endogenous aged group showed significantly higher xanthine oxidase activity, lower superoxide dismutase and catalase activities, and higher expression of MMP-3 mRNA in skin than N group. Therefore, aspectual comparison of the skin change in hairless mice between photo-aged and endogenous aged groups showed different each other, and these results will be useful for skin aging research.
Subject(s)
Aged , Animals , Female , Humans , Mice , Aging , Catalase , Collagen , Elastic Tissue , Epidermis , Erythema , Mast Cells , Mice, Hairless , RNA, Messenger , Skin , Skin Aging , Superoxide Dismutase , Transforming Growth Factor beta , Xanthine OxidaseABSTRACT
PURPOSE: The aim of this study was to examine the effects of silk fibroin film on wound healing of cutaneous burn in hairless mice by using microscopic findings and stem cell markers (nestin, cytokeratin 15) and ki-67 proliferation marker. METHODS: Each mouse received two burns at the dorsal area by applying a metal rod heated with boiling water. Burn wound sites were dressed with Silk Fibroin Film and duoderm (SF group), Aquacel hydrofiber and duoderm (AC group) and duoderm only (Control group). All groups were covered externally with duodermas adhesive bands. Those mice were sacrificed at zero, two, seven, fourteen and twenty one days after burn. Histological findings and immunohistochemical staining for stem cell markers were observed. RESULTS: In SF group, inflammatory cell infiltration, formation of granulation tissue and inflammatory foci are greater than in AC and control group. Those factors appear to enhance mesenchymal stem cell markers such as nestin. Finally mesenchymal tissue regeneration was enhanced. In addition, the length of ki-67 expressed re-generating epithelium, which appeared to be associated with epithelial regeneration, was the longest in SF group. CONCLUSION: The results show that the wound healing effect of SF is the best among other treatment materials including AC in the experimental group and duoderm in the control group through mesenchymal regeneration and epithelial regeneration which are essential factors for wound healing.
Subject(s)
Animals , Mice , Adhesives , Bandages, Hydrocolloid , Burns , Carboxymethylcellulose Sodium , Epithelium , Fibroins , Granulation Tissue , Hot Temperature , Intermediate Filament Proteins , Keratins , Mesenchymal Stem Cells , Mice, Hairless , Nerve Tissue Proteins , Regeneration , Silk , Stem Cells , Water , Wound HealingABSTRACT
Objective To study collagen changes in dermis of hairless mice that were exposed to ultraviolet. Methods The hairless mice was irradiated under UVA, UVB and the combination of the two for 20 weeks, total dose of UVA was 222J/cm~2, and that of UVB was 5.9J/cm~2. After irradiation, the dorsal skin's collagens of animals were analysed by computer imaging analysis system, histopathologic examination, specific stains and electorn microscopy. Results The hairless mice exposed to ultraviolet A were unchanged in dermis collagen. The hairless mice was irradiated under UVB and the both UVA and UVB, and the content of collagen was decreased with less affinity for collagen staining. These findings were supported by electron microscopy, which showed fraying, thickened, and proliferating collagen, coalesced into extensive denaturalization. The ratio of types Ⅲ/Ⅰ+Ⅲ collagen was significantly increased. Conclusion The qualitative and quantitative changes of the collagen in the ultraviolet irradiated skin of hairless mice are related to ultraviolet B but not to UVA. UVB is a key factor of skin collagen damage in UV-irradiation.
ABSTRACT
Objective To study the changes of skin wrinkles in hairless mice while exposed to ultraviolet. Methods The hairless mice were irradiated under long-wave ultraviolet ray (UVA), medium-frequency wave ultraviolet ray (UVB) and the combination of the two for 20 weeks. Total dose of UVA was 222J/cm~2, and that of UVB was 5.9J/ cm~2. After irradiation, the skin wrinkling of animals were analysed by the naked eye, dermatoglyphics enlarges and applied color skin system of pathologic portrait quantitative analysis. Results Control group: The hairless mice skin were fine and delicate, the ditch and ridge of skin distributed even, and had no the obvious cornification. Long wave ultraviolet ray (UVA) set: The skin was slightly rough, skin ditch and ridge distributed still even, and had no obvious cornification; quantitative analysis had no the obvious difference from that of control group. Medium-frequency wave ultraviolet ray (UVB) set: The dermatoglyphics were disorderly, and the skin ditch deepened, widened, and the skin ridge increased the breadth and obvious cornification, and quantitative analysis had obvious difference from that of control group. Long wave and medium-frequency wave ultraviolet ray (UVA+ UVB) set: The dermatoglyphics was disorderly, and the skin ditch deepened, widened, the skin ridge increased the breadth, skin cornification was more obvious, quantitative analysis had obvious difference from that of control group. Conclusions The qualitative and quantitative changes of the wrinkles in the ultraviolet irradiated skin of hairless mice are related to ultraviolet B but not to UVA. UVB is a key factor of skin wrinkling in UV-irradiation.