Study on the effect of microparticle platelet frozen-powder on the healing of skin wound in mouse

Objective To study the effect of microparticle platelet frozen-powder prepared from outdated platelets on wound healing in animal models.Methods Microparticle platelet frozen-powder was prepared by repeated freeze-thawing and lyophilizing outdated platelets. The specific gravity of this powder was 0.28 g/ml. Levels of VEGF,TGFβ1 and PDGF in apheresis platelets and microparticle platelet frozen-powder were measured and evaluated by ELISA. The mouse model with skin wounds on the back was used to study the effect of the powder on wound healing. Kunming mice were randomly divided into control group,plasma group,and microparticle platelet frozen-powder group,with six mice in each group. A 1.2 centimeter-diameter full-thickness wound was made on each side of the mouse mid-back. The treatment was applied to each wound once daily for 14 consecutive days after wounding. The wound area,the percentage of wound contraction and CD31 expression on days 5,7,10,and 14 after wounding were also measured. Results Levels of VEGF were not significantly different in fresh apheresis platelet and microparticle platelet frozen powder(P0.05). Levels of TGF-β1 and PDGF in microparticle platelet frozen powder were higher than those in fresh platelet(P0.05). Wound area was decreased in the microparticle platelet frozen powder group,compared with those in the saline control group and plasma control group on days 5,7 and 10 after wounding(P0 05). The percentage of wound contraction was enhanced in the microparticle platelet frozen powder group compared with those in the saline control group and plasma control group on days 5,7 and 10 after wounding(P0.01,P0.05). CD31 expression was higher in microparticle platelet frozen powder group compared with those in saline control group and plasma control group on days 5,7 and 10 after wounding(P0.01,P0.05).Conclusion Levels of TGF-β1 and PDGF in microparticle platelet frozen powder were higher,which can improve wound healing of mouse.