塞来昔布固体脂质纳米粒对兔角膜重度热烧伤行穿透性角膜移植术后CNV、MMP-2的影响

Effects of Celecoxib Solid Lipid Nanoparticles on CNV,MMP-2After Penetrating Keratoplasty in Severecorneal Thermal Burn of Rabbit

目的观察塞来昔布(celecoxib,CXB)固体脂质纳米粒(solid lipid nanoparticles,SLN)对兔角膜重度热烧伤(severe corneal thermal burn,SCTB)行穿透性角膜移植术(penetrating keratoplasty,PKP)后角膜新生血管(corneal neovascularization,CNV)及基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)浓度的影响,探讨CXB-SLN对兔SCTB的作用机制。方法取36只新西兰白兔,恒温烧灼器制作兔SCTB模型(左眼),随机分为对照组、PKP组、CXB-PKP组,每组12只。对照组、PKP组球结膜下注射9 g/L的生理盐水0.1 ml,CXB-PKP组球结膜下注射1 g/L的CXB-SLN 0.1 ml。PKP组、CXB-PKP组于造模后第3天行PKP治疗。观察3组白兔术后角膜一般情况并记录术后10、20、40天CNV面积。在术后20、40天各组随机选择6只兔处死。采用酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)检测角膜上清液中MMP-2浓度,并分析CNV面积与MMP-2的相关性。结果术前3组白兔角膜均可见角膜缘充血明显,角膜烧伤区水肿,混浊,伴角膜上皮层坏死、剥脱。术后对照组可见角膜混浊逐渐加重呈瓷白色混浊,PKP组与CXB-PKP组可见角膜植片均成活,角膜透明度尚可。术后10、20、40天,CXB-PKP组CNV面积小于PKP组(P均<0.05),PKP组CNV面积小于对照组(P均<0.05)。术后20和40天角膜上清液MMP-2的浓度,CXB-PKP组低于PKP组,PKP组低于对照组(P均<0.05)。术后20、40天,CNV面积与MMP-2浓度呈正相关(r=0.742,P<0.001;r=0.827,P<0.001)。结论CXB-SLN对兔SCTB后的CNV具有明显抑制作用,可减轻角膜混浊,其机理可能与MMP-2的下调有关,能够为SCTB后行PKP创造有利条件。

Objective To observe the effects of celecoxib(CXB)solid lipid nanoparticles(SLN)on corneal neovascularization(CNV)and concentration of matrix metalloproteinase-2(MMP-2)after penetrating keratoplasty(PKP)in rabbits with severe corneal thermal burn(SCTB),and to explore the mechanism of CXB-SLN in rabbits with SCTB.Methods A total of 36 New Zealand white rabbits were selected,the model of rabbits with SCTB(left eye)made with constant temperature cautery were randomly divided into control group,PKP group and CXB-PKP group,with12 rabbits in each.Subconjunctival injection with9 g/L normal saline 0.1 ml was in the control group and the PKP group,and subconjunctival injection with1 g/L CXB-SLN0.1 ml was in the CXB-PKP group.The PKP group and the CXB-PKP group were treated with PKP on the 3rd day after modeling.The general conditions of corneal were observed and the area of CNV was recorded on the 10th,20th and 40th days after surgery.Six rabbits in each group were randomly selected and executed on 20th and 40th days after surgery.The concentration of MMP-2 in corneal supernatant was detected by enzyme-linked immunosorbent assay(ELISA),and the correlation between the area of CNV and MMP-2 was analyzed.Results Limbus corneae hyperemia,edema and opacity in the burned area of cornea,accompanied by necrosis and exfoliation of corneal epithelium were observed in all 3 groups before surgery.After surgery,corneal opacity gradually aggravated and became porcelain white opacification in the control group,while corneal grafts survived and corneal transparency was acceptable in the PKP group and the CXB-PKP group.On the 10th,20th and 40th days after surgery,the area of CNV in the CXB-PKP group was less than that in the PKP group(all P<0.05),and that in the PKP group was less than the control group(all P<0.05).The concentration of MMP-2 in corneal supernatant was less in the CXB-PKP group than that in the PKP group,and that in the PKP group was less than the control group on the 20th and 40th days after surgery(all P<0.05).There was a posi-tive correlation between the area of CNV and the concentration of MMP-2 on the 20th and 40th days after surgery(r=0.742,P<0.001;r=0.827,P<0.001).Conclusion CXB-SLN can significantly inhibit the growth of CNV and reduce corneal opacity after SCTB in rabbits,its mechanism may be related to down regulation of MMP-2,which can create favorable conditions for PKP after SCTB.