Effect of Transplantation of Bone Marrow-derived Mesenchymal Stem Cells on the Apoptosis of Neurons in Ischemic Rats

  Objective  To investigate the apoptosis of neurons in the penumbra of cerebral ischemic rats transplanted with bone marrow derived-mesenchymal stem cells(BMSCs).

  Methods  Bone marrow of a healthy adult volunteer was collected, and BMSCs were cultivated and harvested.Adult rats subjected to 2 h middle cerebral artery occlusion(MCAO)were randomly assigned to the BMSCs-treated group(n=12)and the control group(n=12), in which rats were transplanted with 5×10⁵ BMSCs or saline, respectively, into the ipsilateral brain parenchyma on the 3rd post-MCAO day.The modified neurological severity scores(mNSS)was used to measure functional recovery.On the 14th post-MCAO day, apoptotic cells in the penumbra were detected by TUNEL analysis.On the 28th post-MCAO day, neurons were stained by immunoflu-orescence, and hematoxylin-eosin staining was used to evaluate the relative ischemic volume.

  Results  TUNEL-positive cells were significantly reduced(P=0.017), and in contrast, neuronal nuclei antigen(NeuN)-positive cells were significantly increased(P=0.015)in the penumbra in BMSCs-treated group compared with control group.The relative ischemic volume was decreased in the BMSCs-treated group(28.3±4.5)% compared with the control group(36.8±5.6)%(P=0.041).The mNSS was significantly decreased in BMSCs-treated group at each time point starting on the 14th post-MCAO day compared with control group(P < 0.05).

  Conclusion  BMSCs treatment can decrease ischemic volume and improve functional recovery after cerebral ischemia, which may, at least partially, attribute to the reduced apoptosis of neurons in the penumbra.