OBJECTIVE

To explore the effects of (resolving stasis, promoting collateral circulation) moxibustion on learning and memory ability and the expressions of brain derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) in the rats of vascular dementia (VD) in the microenvironment of neurovascular niche.

METHODS

Using 2-vessel occlusion (2-VO), the VD rat models were duplicated. The neural stem cells (NSCs) labeled with lentiviral vector-mediated enhanced green fluorescent protein (EGFP) were co-cultured with endothelial progenitor cells (EPCs) to structure the NSCs + EPCs implant. The implant was transplanted into the lateral ventricle of VD rats and the VD rat models with neurovascular niche were established. In No.1 experiment, the successful-modeled rats were divided into 3 groups, i.e. a NSCs + EPCs moxibustion group, a NSCs + EPCs blank group and a model group, 12 rats in each one. No any treatment was provided in the model group and the NSCs + EPCs blank group. The moxibustion therapy was adopted in the NSCs + EPCs moxibustion group, in which, the suspending moxibustion technique was applied to "Baihui" (GV 20), "Dazhui" (GV 14) and "Shenting" (GV 24), 20 min at each acupoint. The treatment was given once every day and a 14-day treatment was as one course. Totally, 3 courses of treatment were required. At the end of treatment, Morris water maze experiment was adopted to determine the learning and memory ability of the rats in each group. In the No.2 experiment, the model rats were divided into 3 groups, a NSCs + EPCs moxibustion group, a NSCs + EPCs blank group and a model group, 18 rats in each one. In each group, according to the durations of treatment, 3 subgroups were divided and 6 rats in each one. The intervention method was same as the No.1 experiment. Additionally, after corresponding treatment course, using perfusion, the brains were collected in each subgroup and the slices were frozen. BDNF/TrkB expressions were observed in the immunofluorescence test.

RESULTS

After treatment, in the NSCs + EPCs moxibustion group, the escape incubation was reduced, the time of the first running-cross platform was shortened and the frequency of running-cross platform increased as compared with the model group and the NSCs + EPCs blank group (<0.01, <0.05). The protein expressions were increased in tendency among the 3 courses of treatment in the NSCs + EPCs moxibustion group, indicating the significant differences (all <0.05), in which, the increase of the protein expressions in the NSCs + EPCs moxibustion group was better than the NSCs + EPCs blank group (<0.05, <0.01).

CONCLUSION

The moxibustion therapy is the effective approach to VD in clinical treatment. This therapy up-regulates the BDNF/TrkB protein expressions in the microenvironment of neurovascular niche, co-modulates NSCs-EPCs coupling mechanism, promotes nerve neogenesis and repairs the injured nerve.