In Slowing The Progression Of Osteoarthritis Research On Blocking SDF-1/CXCR4 Signaling Pathway

Objective:To discussed by using AMD3100 blocking stromal cell- derived factor 1( SDF-1)/chemokine receptor 4(CXCR4) signaling pathways in the guinea pig osteoarthritis(osteoarthritis, A).Method:(1) selection of experimental animals: The test selected 35 nine-month-old male Hartley guinea pigs(0.88 kg ± 0.21 kg) were randomly divided into three groups: Group 1 by osmotic mini-pump continuous infusion CXCR4 antagonist AMD3100(N = 13); Group 2 OA primarily as an untreated control group(N = 11); Group 3 continuous infusion by osmotic mini-pump PBS(n = 11). Guinea pig containing 0.2% Xylazine and 1% PBS solution of ketamine anesthesia. All guinea pigs weighed weekly, and were euthanized after 3 months(12 weeks) of treatment, after all guinea pigs knee to remove the line through the whole observation after carefully dissected tissue.(2) Before OA chondrocytes and cartilage explants treatment prior to SDF-1, si RNA CXCR4, or anti-CXCR4 nurtured. MRNA and protein levels of matrix metalloproteinases(MMPs), respectively, using a timed polymerase chain reaction(RT-PCR) and enzyme-linked immunosorbent assay(ELISA) assay.(3) experimental animals treated: as the dorsolateral chest incision and blunt separation(~ 1 cm) subcutaneous pouch is formed, the mini-osmotic pumps were inserted. Before inserting, 200μL pump that is stocked with 44.44 mg / ml AMD3100 + PBS solution(group 2) or simply PBS(group 3). The average rate of 0.15μ pumped liters / hour, in order to dose group receive a second 160μg AMD3100 per animal per day. Due to osmotic pumps duration of six weeks, osmotic pumps need to be replaced during thetreatment time.(4) The results of measurement: the extent of damage to the cartilage modified Mankin’s score was evaluated. SDF-1, glycosaminoglycans(GAGs), MMP-1, MMP-13 and interleukin--1β(IL-1β) staining was measured using ELISA.Results:The data seen after SDF-1 reduced infiltration cartilage proteoglycan staining. SDF-1 by the use of the medium after the glycosaminoglycan and MMP-13 activity was significantly increased, while the use of si RNA CXCR4 or CXCR4 antibody disrupt binding between SDF-1 and CXCR4 after, SDF-1 effect is obvious weakened. Safranin-O staining showed by AMD-3100 treatment in the experimental group, their knee cartilage injury Mankin’s score compared to the control group is the lowest. AMD-3100 treated group, SDF-1, GAG, MMP1, MMP-13, and IL-1β levels in synovial fluid also significantly lower than the control group.Conclusion:Successfully established the guinea pig model of primary OA.Found SDF- 1 and CXCR4 compounds can induce of OA cartilage degeneration.Through the pharmacology blocking SDF- 1 / CXCR4 signaling pathways can significantly weaken the catabolic process of articular cartilage.