Clinical-grade human umbilical cord mesenchymal stem cells affect the improvement of neurological function in rats with traumatic brain injury
Cui Lianxu1, Jiang Wenkang2, Lu Dahong1, Xu Junrong3, Liu Xiaocui3, Wang Bingyun2
1Department of Minimally Invasive and Spinal Neurosurgery, Foshan First People’s Hospital, Foshan 528000, Guangdong Province, China; 2School of Life Science and Engineering, Foshan University of Science and Technology, Foshan 528225, Guangdong Province, China; 3Guangdong VitaLife Biotechnology Co., Ltd., Foshan 528251, Guangdong Province, China
Abstract: BACKGROUND: Traumatic brain injury is one of the most serious neurological diseases with the highest incidence in the world, and there is no effective therapy at present. Studies have shown that mesenchymal stem cells have a certain repair effect on traumatic brain injury.
OBJECTIVE: To investigate the effects of clinical-grade umbilical cord mesenchymal stem cells on the improvement of neurological function in rats with traumatic brain injury.
METHODS: Forty-five rats were divided into three groups, namely sham operation group (n=15), model group (n=15) and stem cell group (n=15). Except the sham operation group, the modified Feeney free fall method was used to establish the traumatic brain injury model in the model and stem cell groups. At 24 hours after model establishment, the model group was implanted with 20 μL normal saline; and the stem cell group was implanted with 20 μL human umbilical cord mesenchymal stem cell suspension, a total of 1×106 cells. At 1, 3, 7, 14, and 21 days after cell transplantation, the neural function of the rats was evaluated by modified neurological severity scores. At 21 days after injection, the ratio of Bcl-2/Bax mRNA was detected by RT-qPCR. The expression levels of gliocyte markers GFAP and IBA1 were detected by RT-qPCR and immunofluorescence method. At 21 days after injection, plasma levels of tumor necrosis factor alpha, interleukin 6 and interleukin 10 were determined by ELISA. Hematoxylin-eosin staining was used to observe the brain tissue structure.
RESULTS AND CONCLUSION: (1) Compared with the model group, modified neurological severity score was significantly lower and the motor function was significantly improved in the stem cell group. (2) Compared with the model group, Bcl-2/Bax mRNA ratio was significantly increased in brain tissue, the expression of GFAP and IBA1 was significantly decreased in the stem cell group, while the expression of tumor necrosis factor alpha, interleukin 6 and interleukin 10 in plasma was not significantly different. (3) Hematoxylin-eosin staining showed that the defect area and edema of brain tissue and neuronal apoptosis were improved in different degrees in the stem cell group. (4) The results show that clinical-grade human umbilical cord mesenchymal stem cells can promote neurological function recovery, reduce neuronal apoptosis and inhibit glial overactivation after traumatic brain injury.
Key words: umbilical cord mesenchymal stem cell, traumatic brain injury, neurological function recovery, glial cell, apoptosis