Anti-Frostbite Effects of Prunus Tomentosa Thunb Total Flavone

The aim of this study is to assess the influence of Prunus Tomentosa Thunb Total Flavone (PTTTF) on rabbits' frostbitten ears and on expressions of Matrix Metalloproteinase (MMP-9) in mouse frostbitten tissues and IL-1β in mouse Peripheral Blood Mononuclear Cells (PBMCs). Twelve New Zealand rabbits were randomly divided into two groups, both ears of each rabbit were frostbitten by liquid nitrogen. PTTTF and triamcinolone acetonide acetate ointment (TAAO) were spread on the left ear for 7 days, and the right ear was not treated as control. Therapeutic effects of the drugs and the pathological changes were observed. Drugs (PTTTF and TAAO) were prophylactically spread on the skin of the paws of mice for 5 days. After paw frostbitten models were established, the agents were consecutively spread for another 2 days. Expressions of MMP-9 in frostbitten tissues and IL-1β in PBMCs were respectively detected by the immunohistochemical method and RT-PCR. Compared with controls, four days later, the swelling inhibiting rate of PTTTF was 26.84%, and was 32.52% seven days later. The therapeutic effect of PTTTF was better than that of TAAO. Pathological changes of PTTTF group showed the effusion of a small quantity of neutrophil granulocytes and the tissue dropsy was not obvious. Expressions of both MMP-9 and IL-1β were significantly decreased in PTTTF group compared with those in model control group. There was no significant difference in expressions of MMP-9 and IL-1β between PTTTF group and TAAO group. We concluded that PTTTF produced a significant therapeutic effect on the frostbite of the rabbits' ears. PTTTF could inhibit expressions of MMP-9 in frostbite tissues and IL-1β in PBMCs to relieve the frostbite inflammation.