Effects of hyperbaric oxygen on behavior and transplanted neural stem cells in rats with chronic stress depression / 中国组织工程研究

ABSTRACT

BACKGROUND:Hyperbaric oxygen as a wel-recognized therapy for ischemic and hypoxic diseases has to be combined with other treatments. OBJECTIVE:To study the effects of hyperbaric oxygen combined with neural stem cel transplantation via tail vein in chronic stress depression rats. METHODS:Of 60 Sprague-Dawley rats, 15 rats randomly selected were given no treatment as normal group, and the rest 45 ones were used to establish a rat model of depression and randomly divided into three groupsmodel group (n=15, without giving any treatment), neural stem cel group (n=15, injection of 1 mL neural stem cel suspension (3×106) via the tail vein) and combined group (n=15, hyperbaric oxygen treatment plus neural stem cel injection). Hyperbaric oxygen treatments were carried out four times per day, for 1 week, and al the treatments were given 24 hours after modeling. Rats in each group were subjected to body mass measurement and sugar water consumption test 1 and 2 weeks after treatment, and open field test within 5 minutes after treatment to observe rat behavior changes. The survival and distribution of CM-Dil labeled neural stem cel s were observed by fluorescence microscopy. The changes in the size, morphology and number of hippocampus neurons in rat were detected by the method of nylon staining. TUNEL method was used to measure the apoptosis of nerve cel s. RESULTS AND CONCLUSION:Compared with the normal group, in the model group, rat’s body weight, sucrose water preference and open field test scores were significantly lower, reduced number of hippocampal neurons with intact structure was found and TUNEL results showed more apoptosis (P<0.05). Compared with the model group, the body weight, sucrose preference and open field test score increased significantly (P<0.05), the number of hippocampal neurons was increased, while the number of apoptotic cel s was reduced significantly in the neural stem cel and combined groups (P<0.05). Compared with the neural stem cel group, these indexes were improved more significantly in the combined group (P<0.05). More CM-Dil positive cel s were found in the combined group than the neural stem cel group (P<0.05). Additional y, the number of hippocampal neurons was higher in the combined group than the neural stem cel group, but lower than the normal group. To conclude, transplantation of neural stem cel s combined with hyperbaric oxygen can improve the depression behavior and apoptosis in the hippocampal neurons in chronic stress depression rats.