A Preliminary Study On Lncrna Associated With Rapid Osteogenesis In Madibular Distraction Osteogensesis

ObjectiveThe models of mandibular distraction osteogenesis,mandibular fracture,mandibles of the puppy dogs and the mandibles of embryo dogs were established.Then find the factors or signal pathways which may be activated during the rapid bone formation by high-throughput sequencing.MethodThe experimental seted up 7 groups: distraction group without consolidation?DO1?,distraction group with 2-week-consolidation?DO2?,30 days embryo group?E?,the puppy 2-week group?P?,,the fracture group for 2weeks?corresponding to the latency period 1 week and the distraction period 1week??MF1?,the fracture group for 4 weeks?corresponding to the latency period1 week,1 week of distraction and consolidation period2 weeks??MF2?and control group?AC?.The number of each group was three.DO1 and DO2 group were randomly selected three healthy adult dogs,weighing about 15 kg,in the right mandibular distraction osteogenesis.After 5 days,the right mandible was distracted to the proximal at a speed of 1 mm / day.The distraction period was 7days.A total of 7 mm gap was expected.The DO1 group was to be executed and the right mandible was collected.The DO2 group was consolidated for 2 weeks after distraction,at the end of the consolidation period the CBCT was taken to observe the osteogenesis.Then the animals were sacrificed and the right mandibles was collected.MF1 and MF2 group were randomly selected three healthy adult dogs,weighing about 15 kg,in the right mandibular fractures and the fracture space was 7mm.Respectively,in 2 weeks and 4 weeks after the CBCT and soon sacrificed the dogs,collecting the right mandibles.E group was selected 3 pregnant dogs about 30 days,taking B ultrasound examination to confirm the number of days.Then those embryos were taken into the experimental group.We also selected three 2 weeks old dogs and three healthy adult dogs into 2 weeks old?P?group and normal adult control?AC?group respectively.The dogs were sacrificed in E,P,and AC groups.Seven groups were subjected to high-throughput lncRNA sequencing.Results1.DO1,DO2,MF1,MF2 animals were successfully completed operation and follow-up observation.There was no significant complication in the experimental dogs,and the distractor and titanium plate were fixed firmly and no loosening.No crack and deformation of the distractor and titanium plate were found.Obvious mesial advancement of right mandibular canine was observed of all dogs,indicating that the right mandible had been successfully elongated by DO and artificial fracture extension.2.A sufficient amount of total RNA was extracted from 7 samples,and the cDNA library needed for lncRNA sequencing was successfully constructed.Each group of high-throughput lncRNA sequencing was successful completed.3.A total of 3504 lincRNAs and 3731 novel_lncRNAs were expressed inthe 7 sample.4.Compared with the DO1 group,E group,P group and AC group,MF1 group,lncRNA TCONS₀0170590 could regulate the target gene LIX1 to regulate the angiogenesis or vaculogenesis and new bone formation in distration osteogenesis.Conclusion1.LncRNA TCONS₀0170590's expression has significant difference in the DO1 group,E group,P group and AC group,MF1 group,thus suggesting that distraction osteogenesis and embryo and puppy development may have some common process.2.LncRNA TCONS₀0170590 negatively regulates its target gene,Lix1,and may be involved in the regulation of vasculogenesis or angiogenesis and new bone formation in the process of distraction osteogenesis.3.The tension,micro-trauma and other factors may be the reason for more rapid osteogenesis in distraction osteogenesis.But the mechanism still need to be further explored.