Effect of Astragaloside Ⅳ Combined with Notoginseng Total Saponins on Angiogenesis After Transplantation of BMSCs in Rats with Cerebral Ischemia / 中国实验方剂学杂志

ABSTRACT

Objective:To investigate the effect of astragaloside Ⅳ（AST Ⅳ）and Notoginseng total saponins （NTS） combined with bone marrow mesenchymal stem cell （BMSC） transplantation on neural repair and angiogenesis in rats with cerebral ischemia. Method:The rats were randomly divided into a sham operation group， a model group， low- and high-dose AST Ⅳ + NTS groups， a BMSC infusion group， and low- and high-dose BMSC infusion+AST Ⅳ （10 and 20 mg·kg^-1） + NTS group （25， 50 mg·kg^-1）. BMSCs were isolated and purified by whole bone marrow adherent culture. The positive expression of surface markers of BMSCs （CD29， CD90， CD34， and CD45） was detected by flow cytometry. The focal cerebral ischemia model was established by middle cerebral artery occlusion （MCAO）. The PKH26-labeled BMSCs were injected into the tail vein of rats in the BMSC infusion group， once a day. The rats in the combination groups received BMSC injection once a day and intragastric administration of drugs twice a day. Other groups were administered twice a day by gavage. The sham operation group and the model group received the same amount of normal saline. Symptoms and signs of neurological deficits were assessed by the Longa method and the cerebral infarction rate was determined by TTC staining. The survival and vascularization ［double positive expression of PKH26/vascular endothelial growth factor （VEGF）］ after transplantation of BMSCs were observed by the immunofluorescence method. The protein expression of Ang1 and TGF-<italic>β</italic>₁ was measured by Western blot. Result:BMSCs were properly isolated and cultured. The identification of surface markers CD29， CD90， CD34， and CD45 was consistent with the characteristics of BMSCs. The neurological deficit score and cerebral infarction rate of the model group were significantly increased （<italic>P</italic><0.01）. All drugs and cell transplantation could alleviate the above pathological changes in varying degrees. The strongest effect was observed in high-dose BMSC infusion+AST Ⅳ+NTS group （<italic>P</italic><0.01）， which was superior to those in the AST Ⅳ+NTS groups or the BMSC infusion group. BMSC injection helped cells survive in the ischemic brain tissues and promoted angiogenesis， and this effect could be enhanced by the combination with drugs. After cerebral ischemia， the expression of Ang1 and TGF-<italic>β</italic>₁ was increased， and the effect in the BMSC infusion+AST Ⅳ+NTS groups was the strongest （<italic>P</italic><0.01）. Conclusion:AST Ⅳ combined with NTS can promote the survival of transplanted BMSCs and facilitate angiogenesis after target repair of damaged blood vessels after cerebral ischemia. The mechanism may be related to the improvement of the local microenvironment in the brain after cerebral ischemia and the promotion of the survival and differentiation of transplanted stem cells.