人骨保护素重组腺病毒抑制去势骨质疏松大鼠骨吸收作用的研究

Effect of recombinant adenovirus vector carrying human osteoprotegerin gene in inhibiting bone resorption in ovariectomized rat model of osteoporosis

目的:观察携带人骨保护素基因的重组腺病毒(recombinantadenovirusvectorcarryinghumanosteoprotegeringene,Ad-hOPG)在大鼠体内表达及对去势骨质疏松大鼠的治疗作用。方法:首先将不同滴度的Ad-hOPG(1×1011～1×1013pfu/L)注入SD大鼠体内,观察其表达特点。然后选用10月龄雌性SD大鼠15只,随机分为假手术对照组、卵巢切除+生理盐水注射组、卵巢切除+Ad-hOPG治疗组,每组5只,分别在去势8周后开始给药,给药后在不同时像点测定人骨保护素(humanosteoprotegerin,hOPG)血清浓度;在给药后第48d时用双能X射线骨密度仪(dualenergyXrayabsorptiometry,DEXA)测定各组大鼠骨密度值,并取大鼠胫骨干骺端做组织切片。结果:1×107～1×109pfu的Ad-hOPG表达时限较短,1×1010pfu则表达了长达46d,选择1×1010pfu做进一步实验;假手术对照组、卵巢切除+生理盐水注射组没能检测到hOPG的血清浓度,而卵巢切除+Ad-hOPG治疗组hOPG的血清浓度第2天就达到25mg/L,6d达到高峰,46d时仍有0.0042mg/L;卵巢切除+Ad-hOPG治疗组的骨密度值明显高于卵巢切除+生理盐水注射组(P<0.01),甚至比假手术对照组还高;卵巢切除+Ad-hOPG治疗组大鼠骨形态学也较假手术对照组明显改善。结论:Ad-hOPG在大鼠体内成功的较长时间表达。

AIM: To investigate expression in vivo of recombinant adenovirus vector carrying human osteoprotegerin gene(Ad hOPG) in rats and its effect in treating ovariectomized(OVX) osteoporosis rats. <METHODS: Firstly, Ad hOPG of different titer(1× 107 to 1× 1010 pfu/mL) were injected into SD rats and the characteristics of its expression were observed. Fifteen female SD rats, 10 month old, were randomly divided into sham operated group(n=5),OVX+ normal saline group(n=5) and OVX+ Ad hOPG group (n=5). All the rats received administration eight weeks after being overiectomized, and the serum concentrations of human osteoprotegerin(hOPG) were detected at different time points.The bone mineral density (BMD) was detected with dual energy X ray absorptiometry (DEXA) at the 48th day after administration in each group, and the tissue was taken from tibia metaphysis to slice up.<RESULTS: The time of 1× 107 to 1× 109 pfu Ad hOPG expression was shorter, but that of 1× 1010 pfu Ad hOPG expression lasted for 46 days, so 1× 1010 pfu was chosen for further trials.The serum hOPG concentrations were not detected in the sham operated group and OVX+ normal saline group, but the serum hOPG concentration in the OVX+ Ad hOPG group had reached 25 mg/L at the second day, and reached the peak at the sixth day, and it remained 0.004 2 mg/L at the 46th day. The BMD in the OVX + Ad hOPG group was evidently higher than that in the OVX+ normal saline group(P< 0.01), and even further higher than that in the sham operated group. The bone morphology in the OVX+ Ad hOPG group was improved evidently as compared with that in the sham operated group. <CONCLUSION: In SD rats, the successful long time expression of Ad hOPG can attain evident effect in treating overiectomized rats with osteoporosis.