ABSTRACT
Objective To study the effect of miR-204 on BDNF/TrkB signaling and pathogenesis on the neuron model of epilepsy. Methods Primary hippocampal neurons were cultured in vitro for 7 days, and were divided into control group, control+BDNF group, epilepsy group, epilepsy+BDNF group , control+miR204 group, epilepsy+miR204 group and ep-ilepsy+miR204+BDNF group. The epilepsy model of hippocampal neurons was established by being exposed to Mg2+free me-dia for 3 hours. The miR-204 lentivirus vector was constructed. The effect of miR-204 on BDNF/TrkB expression was detect-ed by immunohistochemistry, patch clamp and Western blot technique. Results Compared with the control group, the TrkB phosphorylation level was higher in control+BDNF group. The TrkB phosphorylation level was lower in epilepsy+BDNF group than that of control+BDNF group, but it was higher than that of epilepsy group. The TrkB phosphorylation level was higher in epilepsy+miR204+BDNF group than that of epilepsy+BDNF group and epilepsy+ miR204 group. Conclusion BDNF and miR-204 can improve the inhibitory condition of BDNF/TrkB signaling and may play an important role in alleviat-ing epilepsy disease.
ABSTRACT
Objective To investigate the mechanism of brain derived neurotrophic factor (BDNF) regulated by differ-ent isoforms of tyrosine kinase receptor B (TrkB) in epileptic hippocampal neurons. Methods Primary hippocampal neu-rons were cultured in vitro for 7 days, and divided into two groups, ALLN (calcineurin inhibitor) group and Anisomycin (trans-lation inhibitor) group. ALLN group included control group, control+BDNF group, epilepsy group, epilepsy+BDNF group, control+ALLN group, epilepsy+ALLN group and epilepsy+ALLN+BDNF group. Anisomycin group was sub-divided into con-trol group, control+BDNF group, epilepsy group, epilepsy+BDNF group, control+Anisomycin group, epilepsy+Anisomycin group and epilepsy+Anisomycin+BDNF group. The immunofluorescent technique was used to identificate the hippocampal neurons. Epileptiform discharges were detected by electrophysiological techniques. Western blot assay was used to deter-mine the protein expression of TrkB and phosphorylated TrkB (p-TrkB) in all cell groups. Results (1) In ALLN group, the gray value of p-TrkB/TrkB was higher in control+BDNF group compared with that of control group, the value was higher in epilepsy+BDNF group than that of epilepsy group but was lower than that of control+BDNF group. The gray value of p-TrkB/TrkB was lower in epilepsy+ALLN+BDNF group than that of epilepsy+BDNF group, but no significant difference compared with that of epilepsy+ALLN group. (2) In Anisomycin group:the gray value of p-TrkB/TrkB was higher in control+BDNF group than that of control group. The gray value of p-TrkB/TrkB was higher in epilepsy+BDNF group than that of epilepsy group, but which was lower than that of control+BDNF group. The gray value of p-TrkB/TrkB was higher in epilepsy+Aniso-mycin+BDNF group than that of epilepsy+BDNF group and epilepsy+Anisomycin group. Conclusion The decreased ex-pression of TrkB.T can improve the inhibition of BDNF/TrkB signaling, and BDNF can activate BDNF/TrkB signal pathway in epileptic hippocampal neurons. The increased TrkB.FL protein level by ALLN can’t improve the inhibition of BDNF/TrkB signal pathway.