| Backgroud: Migraine is a common nerve vascular disorder with a probablyprevalence of 10%- 20%. It brings about a very serious economic burden for the society. Well, the pathogenesis is not clear at the moment. There are many hypothesis on the pathogenesis, of which the trigeminal nerve vascular reflexology and cytokine mediated dura aseptic inflammation is the dominant theory. The expression of Interleukin 1 beta(IL-1β) in the trigeminal ganglions(TG) of migraine ratis elevated. Moreover, the plasm IL-1βin the peripheral venous blood and jugular vein of migraine patients increases, indicating thatIL-1βmay be involved in the pathogenesis of migraine. However, the mechanism ofIL-1β in migraine, especially the molecular mechanism is still unknown. MicroRNA(miRNA) is a kind of small single-stranded RNA molecule with a length of about 18 to 25 nucleotides. It induces gene silencing by degradating m RNA or inhibiting its expression at the post-transcriptional level. MiRNAs involve in a variety of biological processes such as cell differentiation and apoptosis, as well as a variety of disease processes such as tumor, neuropathy pain and cardiovascular disease. However, there are few studies on the relation of migraine and mi RNA at present..Objective: To explorethe differentially expressed miRNAs in TG between the rats with migraine and the normal rats. To generate a preliminary screening of miRNAs which target on IL-1β gene in these differentially expressed miRNAs and to investigatethe possible molecular mechanism of IL-1β in the pathogenesis of migraine and to look for a new biological marker for prevention and treatment of migraine.Methods: Application of repeated chemical stimulation in the rat dura mater induced inflammation. The rat model of migraine was established. Thirty-four male SD rats, weighting 160-220 g, were randomly divided into sham-operated group and the inflammation soup(IS) 1d, 2d and 3d group. Rats were underwent parasagittal epidural catheterization. All of them had a recovery for 5 days. The IS group rats were given IS 10μl/d respectively. While sham-operated group rats were underwent parasagittal subdural catheterization only.Western blot analysis was used to detect the expression of IL-1β in TG of each group rats.The RNA in rat TG of sham-operated group and IS3 d group was extracted to detect aberrant miRNAs using the mi RNA microarray. Four different types of bioinformatics software were applied to predict miRNAs that directly targeted IL-1β. Then we chose five miRNAs which also belonged to down-regulated miRNAs and three up-regulated miRNAs to validate byquantitative real-time PCR.Results:Five days after parasagittal subdural catheterization,the periorbital pain threshold of ratsdid not changed compared with preoperative ones(P > 0.05). While, after giving IS for 3 days, the periorbital pain threshold of rats decreased significantly(P < 0.05).The expression of IL-1β in rat TG of IS 2d and IS 3d group increased compared with the sham-operated group(P < 0.05). IS 3 d group had a total of 23 differentially expressed mi RNAs compared with the sham-operated group in microarray study chip(ratio > 1.5). Among the 23 aberrant miRNAs, seventeen miRNAs were up-regulated and 6 miRNAs were down-regulated.The results of real-time PCR that rno-miR-3560 was up-regulated and two miRNAs: rno-miR-760-3p, rno-miR-130a-3p were down-regulated were consistent with the microarray results(p< 0.05).Conclusion: Dura mater of rats being given IS repeated stimulation caused decreased periorbital pain threshold of rats. There are differentially expressed miRNAs in the TG between IS3 d group rats and sham-operated group rats. Mi R-760-3p and miR-130a-3p may participate in the molecular mechanisms of migraine by regulating the expression of IL-1β. |
PDF Full Text Request