Cell-penetrating peptdie based on peptide array technique inhibiting NR2B phosphorylation in inflammato-ry pain rats / 实用医学杂志

ABSTRACT

Objective We used peptide array technique to construct a peptide FynP inhibiting the interac-tion between Fyn and PSD95 in vitro therefor with a potential for inbiting NR2B phosphorylation level(p-NR2B). This experiment was designed to examine whether FynP(deliverd with TAT-LK15)can inhibit interaction between Fyn and PSD95 in inflammatory pain rats,and therefore inhibit NR2B phosphorylationin in vivo. Methods TAT-LK15 was complexed with FynP(cell-penetrating peptide Tat-LK15/FynP)or scrambled control FynP(Tat-LK15/mFynP). Changes of p-NR2B were detected using western-blot in SCDH of chronic inflammatory pain rats following intraperitoneal injection of Tat-LK15/FynP,meanwhile,the effect of Tat-LK15/FynP on the interaction between Fyn and PSD-95 was tested by co-immunoprecipitation. Pain control efficacy was evaluated by changes of mechani-cal withdrawal threshold(MWT)and thermal withdrawal duration(TWL)in these rats. Results Interaction be-tween Fyn and PSD-95 was efficiently inhibited by intraperitoneal injection of TAT-LK15/FynP complexes while in-jection of FynP or TAT-LK15/mFynP complexes did not show this inhibitory effect. NR2B phosphorylation level was also inhibited by injection of TAT-LK15/FynP,and the changes of p-NR2B levels were reduced by 52%compared to chronic inflammatory pain rats without treatment. FynP or TAT-LK15/mFynP did not show this effect. Moreover, injection of TAT-LK15/FynP complexes significantly reduced MWT and increased TWL of chronic inflammatory pain rats accordingly. Conclusion FynP delivered by Tat-LK15 can perturb Fyn and PSD95 interaction and then inhibit NR2B phosphorylation activation therfor relieve chronic inflammatory pain.