利塞膦酸钠对骨质疏松大鼠牙槽骨Bcl-2、BAX表达的影响

目的: 观察利塞膦酸钠对骨质疏松大鼠下颌牙槽骨显微结构、抗凋亡因子Bcl-2、凋亡因子BAX表达以及骨细胞凋亡的影响。方法: 30只6月龄雌性SD大鼠,随机分为3 组（每组10只）,即Sham组（假手术组）、OVX组（接受双侧卵巢切除术）和RIS组（接受双侧卵巢切除术,然后给予利塞膦酸钠）;造模3个月后,取各组大鼠下颌骨进行micro-CT扫描,并通过TUNEL染色以及Bcl-2、BAX免疫组织化学染色检测下颌骨骨细胞的凋亡。采用SPSS 13.0软件包对组间数据进行比较。结果: 与Sham组相比,OVX组牙槽骨丧失和骨细胞凋亡明显增多;RIS组与OVX组相比,骨细胞凋亡显著减少,BV/TV显著增加,Bcl-2 表达增加,Bcl-2/BAX比值增加（P<0.05）。结论: 利塞磷酸钠增加下颌牙槽骨中Bcl-2的表达和Bcl-2/BAX的比值,部分逆转去卵巢骨质疏松大鼠的牙槽骨丧失,减少下颌骨骨细胞凋亡。

Effects of risedronates on Bcl-2 and BAX expression in osteoporotic rat mandibular alveolar bone

PURPOSE: This study was to investigate the impact of risedronates on mandibular alveolar bone microstructure, anti-apoptotic factor Bcl-2 and apoptotic factor BAX expression and osteocyte apoptosis in an ovariectomized rat model. METHODS: Thirty 6-month-old female SD rats were divided into 3 groups (ten in each group): Sham group, OVX group (bilateral ovariectomy) and RIS group (bilateral ovariectomy, followed by administration of risedronate). Three months later, the mandibles of all animals were harvested and assessed by micro-CT and histological analysis. Osteocyte apoptosis was observed by TUNEL staining and the expression of Bcl-2 and BAX was evaluated by immunohistochemical staining. The data were analyzed using SPSS 13.0 software package. RESULTS: Ovariectomy caused significant alveolar bone loss and greater osteocyte apoptosis in OVX group than in sham group. The systemic risedronate-treated group exhibited a significant increase in BV/TV and decrease in trabecular separation and osteocyte apoptosis, together with an increase in Bcl-2 expression and the ratio of Bcl-2/BAX, when compared with those of the OVX group (P<0.05). CONCLUSIONS: Systemic treatment of risedronates can increase the expression of Bcl-2 and the ratio of Bcl-2/BAX in mandibular alveolar bone. It partially reverses alveolar bone loss and suppresses osteocyte apoptosis in ovariectomized rats.