Effects of dental pulp stem cell transplantation on the long-term behavior and cAMP response element binding protein in neonatal rats with hypoxic ischemic brain damage / 中国组织工程研究

ABSTRACT

BACKGROUND:cAMP response element binding protein (CREB) is a key protein of memory, which is closely related to long-term memory. It wil provide a new way for the treatment of hypoxic ischemic brain damage (HIBD) to study the effects of dental pulp stem cel s transplantation on the long-term behavior and CREB protein via the lateral ventricle in neonatal HIBD rats. OBJECTIVE:To observe the changes in long-term behavior and CREB protein expression in neonatal HIBD rats after human dental pulp stem cel transplantation, thereby providing scientific evidence for clinical treatment of neonatal HIBD. METHODS:Thirty-six healthy 7-day-old Sprague-Dawley rats were randomly divided into normal, HIBD and cel transplantation group. The hypoxic ischemic brain damage models were established in the brain damage and cel transplantation groups. Twenty-four hours after HIBD, human dental pulp stem cel s were injected into the left lateral cerebral ventricle of rats in the cel transplantation group, total y 3×106 living cel s. Equal volume of normal saline was injected into the left lateral cerebral ventricle of rats in the normal control and HIBD groups. RESULTS AND CONCLUSION:The average time to seek water, the average escape latency and escape distance of the human dental pulp stem cel s group were significantly shorter than those of hypoxic ischemic brain injury group (P<0.01), but longer than those in the normal group (P<0.01). Nissl staining showed that the cel s in the hippocampal CA1 region in human dental pulp stem cel s group were more regular, the number of cel s was significantly higher than that of hypoxic ischemic brain injury group, but stil significantly less than that in the normal group (P<0.05). Immunohistochemical staining results showed that the number of CREB positive cel s in human dental pulp stem cel s group was significantly higher than those in HIBD group, but stil significantly less than those in the normal group (P<0.01). It is suggested that human dental pulp stem cel s transplantation could promote the expression of CREB protein in the hippocampal CA1 region, to improve the long-term learning and memory ability of hypoxic ischemic neonatal rats, and thus repair HIBD.