The purpose of this study was to investigate the effects of Rhodiola rosea extract and depression on the serotonin (5-HT) level, cell proliferation and quantity of neurons at cerebral hippocampus ofdepressive rats induced by Chronic Mild Stress (CMS). Seventy male Sprague-Dawley rats were divided into seven groups (10 per group): normal control group, untreated depressive rat model group, negative control group, positive control group, low dosage Rhodiola rosea extract (1.5g/kg) group, medium dosage Rhodiola rosea extract (3g/kg) group and high dosage Rhodiola rosea extract (6g/kg) group. After the depressive rats induced by CMS had received Rhodiola rosea extract for 3 weeks, the 5-HT levels at cerebral hippocampus were detected by high performance liquid chromatography. Bromodeoxyuridine (BrdU) was injected in vivo to label the proliferating cells at hippocampus, and morphometry was used to count the hippocampal neurons. The results showed that the 5-HT level of the three experimental groups had recovered to normal status. The immunohistochemistry of hippocampus BrdU positive cells had returned to the normal level in the group of depressive rats with low dosage Rhodiola rosea extract. In conclusion the results demonstrated that Rhodiola rosea extract could improve 5-HT level in hippocampus in depressive rats, and low dosage Rhodiola rosea could induce neural stem cell proliferation at hippocampus to return to normal level, repairing the injured neurons at hippocampus.

Bone marrow mesenchymal stem cells (MSCs) are one of the potential tools fortreatment of the spinal cord injury; however, the survival and differentiation of MSCs in an injuredspinal cord still need to be improved. In the present study, we investigated whether Governor Vesselelectro-acupuncture (EA) could efficiently promote bone marrow mesenchymal stem cells (MSCs)survival and differentiation, axonal regeneration and finally, functional recovery in the transectedspinal cord.

To explore therapeutic potential of engineered neural tissue, we combined genetically modified neural stem cells (NSCs) and poly(lactic acid-co-glycolic acid) (PLGA) polymers to generate an artificial neural network in vitro. NSCs transfected with either NT-3 or its receptor TrkC gene were seeded into PLGA scaffold. The NSCs were widely distributed and viable in the scaffold after culturing for 14 days. Immunoreactivity against Map2 was detected in >70% of these grafted cells, suggesting a high rate of differentiation toward neurons. Immunostaining of synapsin-I and PSD95 revealed formation of synaptic structures, which was also observed under electron microscope. Furthermore, using FM1-43 dynamic imaging, synapses in these differentiated neurons were found to be excitable and capable of releasing synaptic vesicles. Taken together, our artificial PLGA construct permits NSCs to differentiate toward neurons, establish connections and exhibit synaptic activities. These findings provide a biological basis for future application or transplantation of this artificial construct in neural repair

Skin-derived precursors (SKPs) are derived from mesoblast and can differentiate into smooth muscle cells, adipocytes, and less neuronal phenotypes. This study demonstrates that retinoic acid (RA) improves SKPs exit from self-proliferation to neural differentiation through up-regulating of NeuroD andcell-cycle regulatory protein p21, meanwhile RA also induces p75 neurotrophin receptor (p75NTR) upregulation and apoptosis of SKPs. When treated sequentially with neurotrophin-3 (NT-3) after RA induction, the survival and neural differentiation of SKPs were enhanced significantly, and cell apoptosis induced by RA was decreased. These effects could be reversed by p75NTR inhibitor Pep5 instead of Trk receptor inhibitor K252a. The results indicate that NT-3 improves the neural differentiation of SKPs induced by RA through a p75NTR-dependent signaling pathway

This study investigated whether electro-acupuncture (EA) would improvethe survival and migration of neural stem cells (NSCs) transplanted ininjured spinal cord as well as the potential mechanisms. TlO spinal cordsegments of 50 adult Sprague-Dawley (SD) rats were completely transected,and then NSCs were immediately transplanted into the transected site of theexperimental animals, while control animals were sham operated withouttransplantation. Five days post-operation, electro-acupuncture treatment onGV9 (Zhiyang), GV6 (Jizhong), GV2 (Yaoshu) and GVI (Changqiang)acupoints was applied for 14 days (EA+NSCs 14d) and 30 days (EA+NSCs30d). ELISA and immunohistochemical staining were used to assess thecontent of neurotrophine-3 (NT-3) and the characteristics of transplantedNSCs. We found that the number of transplanted NSCs the survived inEA+NSCs14d group was significantly increased as compared to that of theNSCs30d group (5825.20+819.01vs 4781.40+500.49, P<0.05).19Immunostaining indicated that some transplanted NSCs developed intomicrotubule association protein 2 (MAP2) positive cells and many of themdeveloped into glial fibrillary acidic protein (GFAP) positive cells in theNSCs30d group. Further, the migration length of transplanted NSCs towardcaudal tissue in the injured site was longer in the EA+NSCs30d group thanthat in NSCs30d group (5.98+0.79mm vs 3.96+1.72mm; P<0.05). AlsoNT-3 in injured spinal cord tissue was 23% increased in the EA+NSCs14dgroup. These results suggest that the combination of EA and NSCs improvesthe survival and migration of NSCs in injured spinal cord in rats.