To investigate the effect of electroacupuncture(EA) on miR-34a-5p, silent mating type information regulation 2 homolog-1 (SIRT1) and nuclear factor-κB subunit p65 (NF-κB p65) in the trigeminal ganglion of rats with migraine, so as to explore the mechanisms of EA underlying prevention of migraine.
Male SD rats were randomly divi-ded into normal, sham operation, model, EA, and EA plus EX527(a SIRT1 inhibitor) groups, with 10 rats in each group. The rat model of migraine was established by electrical stimulation of the trigeminal ganglion. Before modeling, EA was applied at "Waiguan"(TE5) and "Fengchi"(GB20) for 20 min each time, once a day for 5 consecutive days, and intraperitoneal injection of EX527 (5 mg/kg) every day simultaneously. Serum prostaglandin E2 (PGE2) and calcitonin gene-related peptide (CGRP) concentrations were measured by enzyme-linked immunosorbent assay. The levels of miR-34a-5p, SIRT1 and interleukin-1β (IL-1β) mRNA，and protein expression of SIRT1, IL-1β, NF-κB p65, NF-κB Ac-p65 and cyclooxygenase-2 （COX2） in trigeminal ganglia were detected by real-time quantitative PCR and Western blot, separately.
The serum concentrations of PGE2 and CGRP， the expression of miR-34a-5p, IL-1β mRNA and protein, NF-κB p65, NF-κB Ac-p65 and COX2 protein expression in the trigeminal ganglion were remarkably increased (P<0.05), while the SIRT1 mRNA and protein decreased (P<0.05) in the model group in contrast to the normal group. Following EA intervention， the serum PGE2 and CGRP concentrations, miR-34a-5p expression, IL-1β mRNA and protein, NF-κB p65, NF-κB Ac-p65 and COX2 protein expression were significantly down-regulated (P<0.05), and SIRT1 mRNA and protein significantly up-regulated (P<0.05). Compared with the EA group, the serum concentrations of PGE2 and CGRP, IL-1β mRNA and protein, NF-κB p65, NF-κB Ac-p65 and COX2 protein expressions increased (P<0.05), and SIRT1 protein decreased (P<0.05) in the EA plus EX527 group.
In migraine rats, EA can inhibit miR-34a-5p expression in the trigeminal ganglion, increase SIRT1 expression, down-regulate IL-1β/COX2 inflammation signals, reduce PGE2 synthesis, and thus redue CGRP released from the peripheral terminals, which may be one of the mechanisms of EA in preventing migraine.