Functional recovery after acute intravenous administration of human umbilical cord mesenchymal stem cells in rats with cerebral ischemia-reperfusion injury.

Cell therapy is a potential approach for treatment of strokes. Mesenchymal stem cells (MSCs) are a potential cell source for clinical use because they are safe and easy to obtain. A peptide solution can promote neural regeneration. Previously, such a solution was stereotactically injected into the brain of rats with cerebral infarction, resulting in improvement in the animal's neurological function and reduction in the infarction volume, but the injury was relatively severe. The current study established a rat model of cerebral ischemia-reperfusion (I/R) injury. MSCs isolated from Wharton's jelly of human umbilical cords (HUMSCs) were injected intravenously immediately after cerebral I/R injury(3 × 10(6) cells per rat). Twenty-four h and 14 d after surgery, animal behavior was evaluated using the Rogers test and infarct lesion volume was evaluated by 2,3,5-triphenyltetrazolium chloride staining. Fourteen d after surgery, brain tissues were collected at 14 d to study migration/implantation of HUMSCs, cellular proliferation, neural regeneration and astrocyte activation. Compared to cerebral I/R injury alone, HUMSC treatment improved function at 14 d after surgery, with no reduction in infarct volume or migration or implantation of cells into the damaged brain areas. Nevertheless, 14 d after surgery, HUMSC administration increased cellular proliferation and the level of neurofilament 200 level and decreased the level of glial fibrillary acidic protein. After cerebral I/R injury, acute intravenous administration of HUMSCs could promote recovery by activating endogenous neural regeneration and inhibiting astrocyte activation, without migration and implantation directly into lesions.