Total flavone of Abelmoschl manihot L. medic exhibits protective effect against hind-limb ischemia in rat model.

Total flavones of Abelmoschus manihot L. Medic (TFA) is the major active component isolated from Chinese herb Abelmoschus manihot L. Medic. TFA has shown neuroprotective effect against cerebral ischemia injury in rats and rabbits. However, the effects of TFA on hind-limb ischemia and the underlying mechanisms remain unclear. Therefore, in the present study, we used a rat hind-limb ischemia model to investigate protective effect of TFA against limb ischemia injury. The rat model of hind-limb ischemia was established. Treatment groups received TFA at two different doses (160 and 40mg/kg) daily for 10 days. Sham operated control group and model group received saline. At the end the rats were sacrificed, hindlimb tissues were stained with Haematoxylin-Eosin and Masson's trichrome. RNA and protein were extracted from tissues for PCR and Western blot analysis. The results showed that TFA reduced lower limb ischemic injury, recovered tissue volume and diminished fibrosis and muscle degeneration. Mechanistically, we showed that TFA increased the expression of anti-apoptotic factor such as Bcl-2 and survivin, decreased the expression of pro-apoptotic factor such as Caspase 3, Bax and Bak and inhibited the activation of caspase 3 and 9. In summary, this study proves new evidence that TFA protects hind-limb against ischemia injury by inhibiting apoptosis and could be a promising therapeutic agent for acute lower extremity ischemia.