Effect of Tongqiao-Huoxue decoction on hippocampus neuron apoptosis and blood serum nidogen of vascular dementia rats / 国际中医中药杂志

Objective To study the effects of Tongqiao-Huoxue decoction on neuron apoptosis in the CA1 region of the hippocampus and the serum nidogen expression of vascular dementia(VaD) rats and to investigate its mechanism. Methods 40 healthy male SD rats were randomly divided into a normal group, a sham operation group, a model group, a TCM group, and a placebo group. VaD rat models were established by Olsson method. After the models were successfully prepared, the rats in the TCM group were fed Tongqiao-Huoxue decoction, the rats in the placebo group were fed distilled water. Morris water maze test was adopted to investigate their learning and memory abilities, TUNEL was used to assay hippocampal CA1 neurons apoptosis, ELISA kits was used to detect Nestin serum levels . Results The neuron apoptosis index in the CA1 region of the hippocampus in the TCM group was(37.01±2.23)%,which was(55.15±1.54)%in the placebo group;the difference was statistically significant(P<0.05).The serum nidogen was(4.47±0.31)ng/L in the TCM group, which was(3.42±0.43)ng/L in the placebo group;the difference was statistically significant(P<0.05). Compared to the VaD group, escape latency in the TCM group in the third, forth, and fifth day was significantly shorter(P<0.05), the number of cross platforms were significantly increased(t=3.521, P=0.000). Conclusion Tong qiao-Huoxue decoction can improve learning and memory impairment in VaD rats, which may be associated with its increasing serum nidogen expression and decreasing the neuron apoptosis in hippocampal CA1.

Nidogen Plays a Role in the Regenerative Axon Growth of Adult Sensory Neurons Through Schwann Cells

We previously reported that nidogen is an extracellular matrix protein regulating Schwann cell proliferation and migration. Since Schwann cells play a critical role in peripheral nerve regeneration, nidogen may play a role in it via regulation of Schwann cells. Here, we demonstrate direct evidence that nidogen induces elongation of regenerative axon growth of adult sensory neurons, and that the effect is Schwann cell dependent. Continuous infusion of recombinant ectodomain of tumor endothelial marker 7, which specifically blocks nidogen function in Schwann cells, suppressed regenerative neurite growth in a sciatic nerve axotomy model. Taken together, it is likely that nidogen is required for proper regeneration of peripheral nerves after injury.