动物造模,人脐带间充质干细胞 z-bio 2023-03-03 802

　　Objective To investigate whether transplantation of human umbilical cord mesenchymal stem cells can improve learning and memory and cognitive decline by regulating the level of autophagy in naturally aging rats.

　　Methods SD rats were reared in a barrier environment to the age of senescence (24 months old), and the old rats with obvious cognitive decline were selected behaviorally and divided into cell transplantation group (group H) and normal saline group (group C). Rats were the normal group (N group). Group H; 500 μL of hUCMSCs cell suspension was injected into the tail vein at a dose of 2 × 10* each, and groups C and N were respectively injected with sterile normal saline through the tail vein. The time is once a week for 4 consecutive weeks. The changes of learning and memory ability were observed by Morris water maze, Y maze and novel object recognition experiments; the morphological changes of rat hippocampal neurons were observed by HE staining; the relative expression levels of LC3II/I, Beclin1 and P62 in hippocampus were detected by Westem Blot.

　　Results (1) The behavioral results showed that the learning and memory ability of group H and group N was significantly higher than that of group C. (2) In HE staining, neurons in group H and group N in hippocampal CA1 area and DG area were arranged more regularly, with complete cell structure and full nuclei. In group C, the number of neurons in CA1 area decreased, with loose cell arrangement, pyknosis, and degeneration disease. (3) The protein content of P62 in group H and group N was significantly lower than that in group C, and the levels of Beclin1 and LC3II/I were significantly higher than those in group C.

　　Conclusion Intravenous injection of human umbilical cord mesenchymal stem cells improves learning, memory and cognitive decline in naturally aging rats, which may be related to the recovery of autophagy levels after intervention.