| Backgroundskin, As the body’s external organ, not only can reflect the state of the whole body, but also can as a reference to determine the degree of aging. Photoaging skin is the most likely to occur in our daily life, but also the most in need for prevention and treatment. Skin photoaging is a process refers to the sun’s ultraviolet radiation damage and accumulate for a long time. UV radiation can make the skin become rough, dull, and wrinkles. Long-term accumulation will cause dermal inflammation. Macrophages, mast cells, inflammatory neurotransmitters and cytokines arround the blood vessels will be activated, which can lead to tissue dissolving enzymes such as elastase, collagenase release, then slowly dissolved the dermis. More seriously, it will cause skin lesions such as skin cancer.Not all the photoaging are equal, this process is affected by skin type and ethnicity, but also depends on the location, occupation, lifestyle and the protection measures we take. Generally speaking, people affected by the social, cultural and personal values, are very concern about their appearance. While each person’s aesthetic is different, but have eternal youthful appearance is a standard. While each one have different aesthetics, but to have a youthful appearance is an everlasting dream. The degree of photoaging plays an important role in determining whether retain youth. Therefore, how to delay skin aging has become an important scientific problem all over the world.Currently, discussion of how to delay skin photoaging usually in terms of antioxidant, here we study it from nonenzymatic glycosylation and molecular level, to investigate the effects of Chenpi on skin photoaging.objective1、To observe the effect of Chenpi on pathological organization structure and the expression of Hyp, AGEs and AR in back skin of the skin photoaging nude.2、To observe the effect of Chenpi on the expression of protein P16 in back skin of the skin photoaging nude.3、To observe the effect of Chenpi percutaneous fluid on the survival and the expression of β-galactosidase expression of the Skin fibroblasts in photoaging.4、To observe the effect of Chenpi percutaneous fluid on cell cycle and apoptosis of the Skin fibroblasts in photoaging.Methods1-SPF grade female balb/c mice were randomly divided into normal group, model group, the vitamin E group (5g/g) and Chenpi extract high-dose group (lg/g), Chenpi extract low-dose group (0.5g/g). Establish the nude mice model of skin photoaging by UVA and UVB ultraviolet light irradiation. During the 8 weeks, each group were giving appropriate treatment.8 weeks later, take the back skin from the nude mice in each group and observed its pathological structures (HE staining, Masson staining, aldehyde magenta staining);detect the expression of Hyp in the back skin of the skin photoaging nude mice by Colorimetry; detect the expression of AGEs and AR in the back skin of the skin photoaging nude mice by Elisa; detect the protein P16 in back skin of the skin photoaging nude by Wester-blot.2、Get skin fibroblasts from the back skin of the newborn rat, the 4th to 7th generations skin fibroblasts were divided into normal group, model group、 the vitamin E low-dose group (0.01g/ml)、the vitamin E high-dose group (0.05g /ml) and three Chenpi percutaneous fluid group(100mg/mL、50mg/mL、 25mg/mL). Detect the cell viability of the skin fibroblast by MTT assay; to observe the expression of β-galactosidase expression of the Skin fibroblasts in photoaging; detect the cell cycle and apoptosis of the Skin fibroblasts in photoaging by flow cytometry.Results1、The back skin of the normal group nude mice were fine luster without wrinkles、thin、moist and elasticity. The back skin of the model group nude mice were thicken、dull complexion、gloss differential,there are obvious coarse deep wrinkles which showed a typical phenomenon of skin photoaging; the back skin of another three group of nude had different degree of thickening、luster、 wrinkles and swelling, but an improvement compared with the model group.Light microscopy revealed:nude mice skin pathology Staining results can be seen nude normal skin tissue structural integrity, the thickness of the normal epidermis and dermis layer boundaries clearly visible wavy collagen dermal layer of fibrous tissue, and were stained dark blue sky evenly distributed, arranged regularly ordered and tightly delivered, a clear outline of the elastic fibers, woven into a mesh, slender form and rules; nude model group obviously visible epidermal hyperkeratosis, epidermal thickening, layered unclear, glandular body significantly reduced, the dermal layer of cells and arranged to reduce confusion, dilated blood vessels, some congestion, there is a clear lymphocytes and eosinophil infiltration, collagen fibers uneven staining and light color, evacuation, some thickening or binding showed clumps, irregular, reducing the number of elastic fibers, like most of a fracture and no outline border, chunky twist, some stain; Citrus high and low dose groups were improved nude skin photoaging pathological structures, including high-dose group results better.2、Hyp dorsal skin of nude mice model group decreased expression (P<0.05) compared with the normal group, AGEs increased expression compared with normal group (P<0.05), AR compared with the normal group showed no significant difference, P16 protein expression increased compared with the normal group (P<0.05), while the orange peel extract can significantly improve the Hyp content (P<0.05) and a decrease in the activity of AGEs trend (P<0.05), decreased the expression of P16 protein (P<0.05), but had no significant effect on the expression of the AR.3、Normal skin fibroblast survival rate is high, between tightly packed cells, the cells showed a slender fiber form; and after the model set by ultraviolet irradiation, the survival rate was significantly lower (P<0.05), shrink, round, cytoplasm visible black dots, suspended cells increased; vitamin E group and Citrus high, have different degrees of reduction in the low-dose group were suspended and atrophy of skin fibroblasts, and most full fusiform morphology, in which high-dose Citrus optimal set of effects.4、Normal skin fibroblast apoptosis rate was 4.91%, while the skin fibroblast apoptosis by UV irradiation was 44.97%, significantly increased the number of apoptotic cells, after treatment with different drugs at different concentrations, showing that apoptosis rate there are different degrees of decline, which 100mg/ml orange peel effect optimal percutaneous permeate; but no significant changes between the groups into cell cycle of skin fibroblasts.Conelusion1、The Lesions of mice model:mice model showed a significant symptoms of skin photoaging, the skin showed a deep and noticeable wrinkles, reduce gloss. The pathological of epidermis were thickening, and the fibroblasts were decreased, Collagen fiber were evacuation, eastic fiber were breakage or gathered. All of this indicated we have successful copy the mode of skin photoaging. The extract of Chenpi can effectively improve the skin photoaging symptoms and reduce coarse deep wrinkles, through the protection of collagen fibers and elastic fibers, and increased hydroxyproline content in the skin, reducing the non-enzymatic glycation end products and senescence associated protein P16, while reducing apoptosis of dermal fibroblasts because ultraviolet radiation, so as to resist the effects of skin photoaging.2、Non-enzymatic glycation features:Non enzymatic glycosylation effect on skin aging is mainly through the collagen fibers and implementation. With the increase of products of Non enzymatic glycosylation, the synthesis of collagen fibers and the promotion were degraded, and hydroxyproline is intradermal content which is rich and relatively stable, the content of hydroxyproline can direct reflect the content of collagen fibers in dermis; at the same time to form a non-enzymatic glycation end product of elastic fibers and elastin in the extracellular fluid glucose non-enzymatic glycation occurs, the elastic fiber breakage, cross-linked aggregates, elasticity disappear eventually lead to skin aging. At present, the domestic research on the mechanism of skin photoaging nonenzymatic glycosylation reaction is still rare.3、The characteristic of senescent fibroblasts is describing like:dermal and cuticle form skin, the aging of dermal is the crucial part in the aging of skin, therefore, the aging of dermal fibroblasts is essential to the aging of skin, and the important abstract of aging cells’study are the research of skin fibroblasts’aging inheritance cells’expression and the research of skin fibroblasts’dying. The main gene in cells’aging is P16, which accumulates P16 protein in aging. It expresses easily when copy cells, at the meanwhile, the dying of cells is pretty significant in the balance of maintaining cells’proliferation and losing. Too much cells’dying is easily induce degeneration and senile disease and many aging appearance. The dermal fibroblasts are dying easily when they are in the induction of ultraviolet rays stress and become old.4、The intervention effect of Chenpi extract:the intervention mechanism of Chenpi extract on skin photoaging may be through the inhibition of non-enzymatic glycosylation reaction, reduce the expression of AGEs and P16 protein and increased the expression of Hyp, at the same time be achieved by reducing the apoptosis of cell owing to oxidative stress. |
PDF Full Text Request