A Preliminary Study To Explore The Effect Of Total Flavonoids From Rhizoma Drynariae On Distraction Osteogenesis Based On The BMP-Smad Signal Path

ObjectiveTo analyze the effect of Distraction Osteogenesis (DO) on the treatment of bone defect, and discuss the deficiency in the clinical application of distraction osteogenesis by reviewing the previous cases.To create a novel distraction osteogenesis model of rat in tibia, to establish basis for the later experiments.To observe the effect of total flavonoids from Rhizoma Drynariae on distraction osteogenesis model based on the The expression of BMP-smad pathway.MethodsReview of the distraction osteogenesis cases:through to January 2013 to 2016 February,7 cases employing distraction osteogenesis technique in our hospital were involved. To observe the velocity of the bone growth and healing time of the bone defect by analyzing the imaging data, then summarize the common complications.A customized external fixation device was attached to the right tibia of 40 male Sprague-Dawley rats. A 4-mm bone block was resected and the tibia was shortened. To investigate the bone healing during the distraction osteogenesis period and reconstruction period, and general observation, x-ray analysis, and histomorphology were performed.80 Sprague-Dawley(SD) rats were randomly divided into model group, traditional Chinese medicine group, inhibitor group and inhibitor combined with traditional Chinese medicine group. From the beginning of the distraction, the groups were given drug intervention. The traditional Chinese medicine group and inhibitor combined with traditional Chinese medicine group were given by gavage once a day with total flavonoids from Rhizoma Drynariae, model group and inhibitor group were given by gavage with saline in the same volume. At the same time, LDN193189HC1 were given by intraperitoneal injection in inhibitor group and inhibitor combined with traditional Chinese medicine group in dosage of 3mg/kg, Saline were given in the same way in model group and traditional Chinese medicine group. Once a day for 30 days. After intervention, X-ray and micro-CT were performed to compared general situation, qPCR was performed to observe the gene expression in BMP-smad pathway at transcription level. Western blot was performed to analyze the protein expression in BMP-smad pathway. One-way analysis of variance was performed to analyze the correlation of the outcome among different groups.result:Clinical case review.7 cases of bone defects were healed with one case of pin infection, the average time of follow-up was 18+5.6months, there was no refracture during the follow-up period.A novel distraction osteogenesis model of rat in tibia. The modeling of 40 SD rats and distracting by adjusting of external fixator distraction were all completed. After 60 days of accomplishment, the external fixator was still stable and effective without hindrance, The tibia length was recovered and bone union was achieved.The effect of total flavonoids from Rhizoma Drynariae on distraction osteogenesis based on the BMP-Smad signal path. In general evaluation of X-ray and micro-CT, comparing with the model group, the quality and velocity of osteogenesis in traditional Chinese medicine group were raised in later phase, and the inhibitor combined with traditional Chinese medicine group also significantly raised comparing inhibitor group. Comparing with the model group, gene expression of the main factors in traditional Chinese medicine group in BMP-Smad signal path, including BMP2, BMP4, BMPR1A, Smadl increased significantly (P<0.05). Comparing with the model group, gene expression of the main factors in BMP-Smad signal path, including BMP2, BMP4, BMPR1A, Smadl in inhibitor group decreased significantly (P<0.05). There were no signifcant difference of protein expression in Western blot between traditional Chinese medicine group and inhibitor group(P>0.05). Comparing with model group, protein expression of main factors of BMP-Smad signal path, including BMP2, BMPR1A, p-Smadl in inhibitor group decreased significantly (P<0.05).Conclusion:Clinical case review. The clinical effect of distraction osteogenesis in the treatment of bone defect is definite. However, there may be some complications in the long period of treatment.The establishment of SD rat model of distraction osteogenesis. A novel SD rat model of distraction osteogenesis in tibia is successfully established, it’s reliable and practical, and can be repeated.The effect of total flavonoids from Rhizoma Drynariae on distraction osteogenesis based on the BMP-Smad signal path. Total Flavonoids of Rhizoma Drynariae can promote osteogenesis in rat model of distraction osteogenesis, which might be related to improving mRNA expression of the BMP-Smad signal path.