Study On The Mechanism Of Electroacupuncture Up-regulating HIF-1α / Sox9 Signaling Pathway In The Treatment Of Middle-stage Osteoarthritis In Rats

Objective:To observe the effect of electroacupuncture on cartilage and subchondral bone in rats with middle-stage osteoarthritis,and to explore the role of HIF-1α / Sox9 in the treatment of rats with middle-stage osteoarthritis by electroacupuncture.Methods:Twenty-four 3-month-old male SD rats weighing 250-300 g were randomly divided into a sham-operated control group(control group),an osteoarthritis model group(osteoarthritis group),and an osteoarthritis model electroacupuncture intervention group(electroacupuncture group),8 per group.Rats were given unlimited water and standard feed.Rats in the osteoarthritis group and the electroacupuncture group replicated the osteoarthritis model through anterior cruciate ligament excision(ACLT).In the control group,only the bilateral knee joints were cut without damaging the cruciate ligament,and the joint capsule and skin weresutured.The rats in the electroacupuncture group began to receive electroacupuncture treatment at 12 weeks after surgery,once a day,30 minutes each time,5 days a week,and the treatment course was 12 weeks;The electroacupuncture was set to sparse and dense wave mode,and the pulse output frequency is 3 / 15 Hz,the intensity is 1mA,the local muscles start to twitch,and the rats do not struggle to the degree.The rats in the control group and the osteoarthritis group were placed in the same environment without intervention.All experimental rats were sacrificed on the day after the last electroacupuncture treatment.Blood was taken from the orbit of the rats,and the expression levels of IL-1 and IL-6 were detected by ELISA;The tibia plateau of the left knee of the rats was stained with HE and safranine O,and the mankin score was scored;Radiation micro-CT scanning and three-dimensional imaging were used to observe the changes of cartilage and subchondral bone microstructure;Western blot was performed to detect the relative expression of HIF-1α,Sox9,MMP13,ADAMTS5,ACAN and other proteins in the rat right femoral condyle.Results:1.ELISA: Compared with the control group,the serum IL-1 and IL-6 expression in the osteoarthritis group increased,but the difference was not statistically significant(p>0.05);compared with the osteoarthritis group,the serum in the electroacupuncture group The expression of IL-1and IL-6 increased,but the difference was not statistically significant(p>0.05);2.Histopathology: Compared with the control group,the osteoarthritis group showed cartilage damage and erosion,and the mankin score was significantly increased(p<0.001);The rats in the electroacupuncture group had significantly improved cartilage damage compared with the osteoarthritis group,and the mankin score was lower than that in the osteoarthritis group(p<0.01);3.Quantitative analysis of subchondral bone microstructure:Compared with the control group,the BV/TV value of the osteoarthritis group decreased,the difference was not statistically significant(p> 0.05),the Tb.Th value decreased,and BS/BV,Tb.N,Tb.Sp all showed Elevated to varying degrees,the differences were statistically significant(p<0.05).Compared with the electroacupuncture group,BV/TV,BS/BV,and Tb.Sp in the osteoarthritis group increased to varying degrees,and Tb.Th and Tb.N decreased to varying degrees,but the differences were not statistically significant(p> 0.05);4.Three-dimensional micro-CT imaging: no obvious bone defect and osteophyte formation in the control group.Compared with the control group,the three-dimensional imaging of the osteoarthritis group showed uneven bone surface,partial cartilage defects,and some osteophyte formation.Compared with the osteoarthritis group,part of the bonesurface of the electroacupuncture group was uneven,with a small amount of cartilage defects and only a small amount of osteophyte formation;5.Western blot: Compared with the control group,the expression levels of HIF-1α,Sox9 and ACAN in the right femoral condyle of the osteoarthritis group were significantly reduced,and the expression levels of MMP13 and ADAMTS5 were significantly increased;Compared with the osteoarthritis group,the expression levels of HIF-1α,Sox9 and ACAN in the right femoral condyle of the electroacupuncture group were significantly increased,while the expression levels of MMP13 and ADAMTS5 were significantly reduced.Conclusion:1.Electroacupuncture can delay cartilage degeneration,and at the same time delay the progress of OA by improving subchondral bone reconstruction;2.Electroacupuncture may inhibit cartilage damage and delay cartilage degeneration by promoting the expression of HIF-1α / Sox9,inhibiting the expression of MMP13 and ADAMTS5,and up-regulating the expression of ACAN.