Research Of Radiation With Electron Linear Accelerator On The L929 Fibroblasts, As Well As The Primary Study Of PQQ (Pyrroloquinoline Quinine) On The Treatment Of Acute Radiation Burn

Objective: After radiation with high energy electronic ray simulatedβ-rays on fibroblast L929 cells and rat skin, to observe proliferation and apoptosis of cell, further to explore the cell mechanism ofβradiation injury; to use PQQ, to observe the rat acute skin injury after the treatment of PQQ.Method:①After L929 cells irradiated with 10Gy dosage ofβ-rays, proliferation of cells was detected by MTT; after cell synchronization, the cell cycle progression was detected by flow cytometry at 4h,8h,12h,24h,36h,48h,expression of Caspase-3 mRNA determined by RT- PCR.②After SD rat buttock skin irradiated with 45Gy dosage ofβ-rays, by the injection, oral administration(300mmol/L,2mg/kg weight) of PQQ, using SOD, MDA and NOS test kit, take overall photographs of irradiation wild skin, HE staining to detect the development of inflammation, changes of dermal fibroblasts and hair follicle cells and epithelial cells, the injury changes of collagen fibers.Result:①A fterβ-radiation, L929 cell growth curve was inverted "Z" shape. Compared to control group, experimental group emerges significant decrease of the optical absorbance value at 570nm in 24h.The value (A570) of two groups increased up to the maximum in 4d ,but experimental group was lower than control group.A clear apoptosis rate of Irradiated cells is 7.379% and 10.287% in 4h and 24h.At the transcriptional level, Caspase-3 expression have significantly increased than normal cells at 24h,36h,48h. L929 cells showed the G2/M phase was delayed, cells gradually increase, reached its highest point in 24h, 65.965%.②After skin radiation injury, the contents of MDA and NOS increased Skin and plasma, while the contents of SOD decreased. After to use PQQ , the contents of MDA, NOS decreased, PQQ injection group was lower than oral group, but were higher than the radiation control group (P≤0.05); the contents of SOD has increased, PQQ injection group was higher than PQQ oral group, but is lower than radiation control group (P≤0.05). The overall level, radiation control group appears a complete hair shed, swelling, peeling and ulcers in the fifth week, two PQQ treatment groups appear hair shed, only minor peeling, no swelling and ulcers. By HE staining, necrosis of epidermal cells, dermal fibroblast and hair follicles cells of the radiation skin, inflammatory cell infiltration, the collagen fibers fracture, polar disappeared, after to use PQQ the acute skin inflammation Lighten, the collagen fibers fracture reduces, good polarity, even the cells and collagens repair regenerates.Conclusion: Afterβ-ray irradiation, the cell proliferation was inhibited both on cell and tissue level, the cells showed apparently death and apoptosis. The mechanism of apoptosis may be related to the Caspase-3 apoptosis pathway. Through activating the oxidoreductase system and reducing the free radicals, PQQ preformed the obvious therapeutic effect of acute skin injury, probably by means of inhibiting the development of acute inflammation, slowing down the degeneration and fracture of collagen fibers, and lightening the injuries of fibroblast and hair follicles in the epithelial and dermal layers.