An Animal Experiment Study Of PLLA/CS Ordered Controlled Release Parthenolide And Naringin In The Treatment Of Periodontitis

[Objectives]To provide the theory basis for the periodontitis treatment with PLLA/CS controlled release system containing natural monomeric compounds,parthenolide with anti-inflammatory effect and naringin with osteogenesis effect,on the rat periodontitis model and periodontal regeneration model.[Methods]A randomized and control study,130 male SD rats were divided into healthy group,ligation+surgery group,pLLA/CS scaffold group,PLLA/CS controlled release system with parthenolide and naringin group and positive control group.The 2-0 ligature was placed around the right mandibular first molar on the 130 male SD rats.One week later,a bony defect was created on the buccal roots of the right mandibular first and second molars by an extraoral buccal approach.After two,four and eight weeks,the first and second molars' gingival tissues and the mandibles were collected for analysis.The distance between the cemento-enamel junction(CEJ)and the alveolar bone crest(ABC)and the bone density of the surgical defects were measured by Micro-CT scanning system;the anti-inflammatory and osteogenesis genes mRNA expression levels of IL-6,IL-1?,MMP-2,MMP-9,ALP,OPG and RANKL were measured by qRT-PCR;the number of inflammatory cells was demonstrated routinely with hematoxylin and eosin(HE)staining;the osteoclasts were observed with tartrate resistant acid phosphatase(TRAP)staining;the expression levels of TNF-? and ALP were determined with lmmunohistochemistry(IHC)staining.[Results]1)Micro-CT scanning:The distances between the CEJ and ABC of the PLLA/CS controlled release system group and the positive control group were lower than those of other groups at 2,4 and 8 weeks(P<0.05).The bone density of surgically periodontal defect in these two groups was significantly increased at 2,4 and 8 weeks(P<0.05).2)qRT-PCR test:Compared with the ligation+surgery group and scaffold group,the mRNA expression levels of IL-1?,MMP2,MMP9 and ALP in the gingival tissue increased but no significant in the controlled release system group and positive group at 2,4 and 8 weeks(P>0.05).At 4 and 8 weeks,compared with the ligation+surgery group,the IL-1? and MMP9 mRNA expression levels were increased significantly in the PLLA/CS controlled release system group(P<0.05),and the MMP9 mRNA expression level was significantly increased in the positive control group(P<0.05).Compared with the ligation+surgery group,the ALP mRNA expression in the positive control group was significantly increased at 2 and 8 weeks(P<0.05).Compared with the PLLA/CS scaffold group,the ALP mRNA expression in the PLLA/CS controlled release system group was significantly decreased at 4 weeks but significantly increased at 8 weeks(P<0.05).3)HE staining:Compared with the ligation+surgery group and the PLLA/CS scaffold group,the inflammatory infiltration degree of the PLLA/CS controlled release system group and the positive control group was increased but no significant at 2 weeks(P>0.05).Compared with the PLLA/CS scaffold group,the inflammatory infiltration degree of the positive control group was significantly decreased at 4 weeks(P<0.05).Compared with the ligation+surgery group and the PLLA/CS scaffold group,the inflammatory infiltration degree of the PLLA/CS controlled release system group and the positive control group was significantly decreased at 8 weeks(P<0.05).4)TRAP staining:Compared with the ligation+surgery group,the number of osteoclasts in PLLA/CS controlled release system group was significantly decreased at 2 weeks(P<0.05).Compared with the ligation+surgery group and the PLLA/CS scaffold group,the number of osteoclasts in the PLLA/CS controlled release system group and positive control group was significantly increased at 4 weeks(P<0.05).Compared with the PLLA/CS scaffold group,the number of osteoclasts in the PLLA/CS controlled release system group and positive control group was significantly decreased at 8 weeks(P<0.05).5)IHC staining:At 2 weeks,compared with the ligation+surgery group,the expression of TNF-? was significantly decreased in the PLLA/CS controlled release system group(P<0.05),compared with the PLLA/CS scaffold group,the expression of ALP was increased but no significant in the PLLA/CS controlled release system group and the positive control group(P>0.05).At 4 weeks,compared with the ligation+ surgery group and the PLLA/CS scaffold group,the expression of TNF-? and ALP was significantly increased in the PLLA/CS controlled release system group(P<0.05).At 8 weeks,compared with the ligation+surgery group and the PLLA/CS scaffold group,the expression of TNF-? was significantly decreased and the expression of ALP was significantly increased in the PLLA/CS controlled release system group and positive control group(P<0.05).[Conclusions]1)By sequentially releasing parthenolide and naringin,the PLLA/CS controlled release system exhibits anti-inflammatory effect and osteogenesis effect on the rat periodontitis model and periodontal regeneration model.2)With the PLLA/CS controlled release system,the anti-inflammatory effect was observed in 2 weeks but weaken after 4 weeks.The osteogenesis effect was demonstrated in 8 weeks.