OBJECTIVETo observe the effect of Astragalus Injection (ASI) combined with rat's mesenchymal stem cells transplantation (rMSCs) for repairing spinal cord injury in rats.

METHODSOne hundred and twenty Wistar rats were randomly divided into 6 groups, named respectively by letters from A-F. they were treated respectively with none, PBS solution, ASI, rMSCs, and ASI + rMSCs, with the ASI administered via intraperitoneal injection and the rMSCs given by local injection to the spinal cord, on the 3rd day of operation. The condition of nerve function recovery was assessed on the 7th, 14th, 21st and 28th day after treatment by scoring according to the Basso-Beattie-Bresnahan (BBB) locomotor rating scale. Besides, the pathological change of the injured spinal cord was observed and expressions of glial fibrillary acidic protein (GFAP) and neurofilament-M (NF-M) in the BrdU-labeled rMSCs in the spinal cord tissue were examined by immune histochemistry.

RESULTSThe recovery of spinal cord in Group D, E and F was better than that in Group B and C, showing higher BBB scores. As compared with Group E, Group F showed a higher score of nerve function and a milder inflammatory cell infiltration with lessened tissue edema in the spinal cord and more active proliferation of gliacyte. Double-labelled immunohistochemical examination showed that the transplanted rMSCs were alive in the host's spinal cord, revealing the expressions of GFAP and NF-M from the 7th day after transplantation, which were migrating to the injured site. The amount of GFAP and NF-M positive cells in Group F was much more than that in Group E (P < 0.05)

CONCLUSIONTransplantation of rMSCs is an effective method in treatment of the spinal cord injury; ASI has the capacity for inducing rMSCs differentiated into neurons, and could synergize with rMSCs to promote the repairing of the spinal cord from injury.