Bioinformatics Analysis Of Low-intensity Pulsed Ultrasound On Temporomandibular Joint Osteoarthritis

ObjectiveTo investigate the mechanism of low-intensity ultrasound(LIPUS)in the treatment of temporomandibular joint osteoarthritis(TMJ-OA)in rats,and to explore the target genes for the treatment of osteoarthritis.Methods1.Rat TMJ-OA model was established by unilateral occlusal trauma(UOT).Rats were divided into control groups and experimental groups randomly.Each group was divided into 4 subgroups,including 4 weeks,8 weeks,12 weeks and 16 weeks.The weight was recorded after the operation.The pathological changes were evaluated by HE and Safranin-O staining.2.TMJ-OA rats were treated with LIPUS.Rats were divided into five groups: control group,recovery group,placebo group,treatment group and occlusal trauma group.The pathological changes were evaluated by HE and Safranin-O staining.Thedifferently expressed genes between placebo and treatment groups were detected bytranscriptome sequencing technology.Then,the sequence data were analysed by bioinformatics.Some selected genes were validated by q RT-PCR and western blot(WB).Results1.Rat TMJ-OA model was successfully established by UOT.In theearly-stage of the experiment(1,2 weeks),UOT had a great influence on the body weight of experimental rats against control rats(P<0.05).Atthe time-point of 8 weeks,UOT group showed obvious cartilage lesion.The modified Mankin score of control and UOT groups at 8 weeks were 4.33±0.52 and 8.67±1.67 repectively,P=0.000.2.LIPUS had a therapeutic effect on TMJ-OA caused by UOT.Through sequencing and bioinformatics analysis,58 genes were found significantly different,including 20 up-regulated genes and 38 down regulated genes(treatment group / placebo group).Through bioinformatics analysis,the following genes were selected and verified.The results of q RT-PCR of ADAMTS-8,Per-2,Fndc-5,C1 qa,C3,C5 a R1,Itg?L,Itgb2,Serpine1,TNNC1 proved that these genes significantly regulated by LIPUS.LIPUS up-regulated the expression of Per-2?C1qa?C3?C5a R1?Itg?L?Itgb2?Serpine1 and down-regulated the expression of ADAMTS-8 ? Fndc-5 ? TNNC1(P<0.05).LIPUS significantly up-regulated the expression of per-2 and down-regulated the expression of ADAMTS-8 in TMJ at the protein level.ConclusionsUOT can lead to a stable TMJ-OA in rats.LIPUS can attenuate TMJ-OA caused by UOT.The therapeutic effect of LIPUS on TMJ-OA may be related to the up-regulation of Per-2 and the down-regulation of ADAMTS-8.