Effect Of N-Isopropylacrylamide-Modified Polyethylenimine-Mediated Oligodeoxynucleotide MT01 Delivery On Experimental Tooth Movement

Objective:Local injection was used in this study in order to observe the effect of N-isopropylacrylamide-modified polyethylenimine-mediated oligodeoxynucleotide MTO1 delivery on biosafety and tooth movement distance in experimental rat tooth movement,which was compared with MT01 and sulfuration-modified MT01(MT01s).The effects of alveolar bone remodeling on experimental tooth movement rats were preliminarily illuminated,which laid the experimental foundation for the regulation of tooth movement during orthodontic treatment.MethodsForty-eight Wistar male rats were randomly divided into PEN group,MT01 group,sulfuration-modified MTO1(MTO1s)group and PEN/MTO1 group.The rat experimental tooth model was established,and the above four drugs were locally injected into the mesial buccal mucosa of first molar in the left sides as the drug intervention side once every 3 days,and the same mass of PBS were injected in the right sides as the control side.After 14 days the rats were sacrificed.The heart,liver,spleen,lung and kidney tissues of rats in various groups were harvested,and their histopathological changes were observed by HE staining.The alveolar bone tissues of the maxillary first molars were isolated and the gross photos and X-ray films were taken to measure the distance of tooth movement.Meanwhile,the expression levels of osteogenic marker genes Runx2,Sp7 and OCN mRNA in the periodontal tissues around the maxillary first molars of rats in various groups were detected by real-time PCR.Results:1.The experimental model of tooth movement in rats were successfully established.After local injection of the above drugs,no obvious inflammatory cell infiltration and structural differences were observed in heart,liver,spleen,lung and kidney of the rats and no obvious abnormalities were observed in all organs among all the groups.2.After the local injection of various drugs on the drug intervention side of rats,compared with the PBS control side,the moving distance of the first molars in the drug intervention side of the MT01,MT01s and PEN/MT01 group was reduced(P<0.05 or P<0.01),but there was no significant difference in PEN group(P>0.05).The data of the distance between the two teeth of the rats in various groups was:PEN/MT01 group>MT01s group>MT01 group>PEN group,and the difference between PEN/MT01 group and MT01s group was statistically significant(P<0.05).3.After the local injection of various drugs on the drug intervention side of rats,the expression levels of Runx2,Sp7 and OCN in the periodontium tissue in the drug intervention sides of the rats in MT01s and PEN/MT01 groups were significantly higher than those in the PBS control sides(P<0.05 or P<0.01),especially in PEN/MT01 group.The expression level of Runx2 in the periodontium tissue in the drug intervention side of the rats in MT01 group was decreased(P<0.05),and the expression level of Sp7 and OCN in the periodontal tissue of the rats in MT01 group were increased(P<0.05),compared with the PBS control side.The expression level of Runx2 in the periodontium tissue in the drug intervention side of the rats in PEN group was decreased(P<0.05),and there were no significant differences in the expression level of Sp7 and OCN between the PBS control side and the drug intervention side(P>0.05).Conclusions:N-isopropylacrylamide-modified Polyethylenimine can transfer MT01 into the cell safely and efficiently;it can decrease the tooth movement distance in the experimental tooth movement rats and increase the expression levels of Runx2,Sp7 and OCN in the periodontium tissue,and it has a certain regulatory effect on alveolar bone remodeling in experimental rat tooth movement.