生命早期负性应激对大鼠实验性牙周炎的影响

目的:探究生命早期负性应激对大鼠成年后实验性牙周炎进展的影响。方法:在3周龄雄性SD大鼠建立慢性温和不可预知应激(unpredictable chronic mild stress, UCMS)模型,以正常饲养大鼠为对照。应激5周后对所有大鼠右上第二磨牙进行实验性牙周炎处理。通过行为学实验评估大鼠情绪状态;ELISA检测血清皮质酮、IL-1β和TNF-α水平;HE染色观察破骨细胞数目,测量牙槽骨丧失量。结果:UCMS大鼠出现糖水偏好下降(P<0.001)、强迫游泳实验中不动时间增加(P<0.01)等抑郁样行为;血清皮质酮及炎性细胞因子水平升高(P<0.05)。HE染色可见UCMS大鼠牙周炎侧牙槽骨吸收量最大,其次为对照组牙周炎侧,再次为对照组正常侧(P<0.001);破骨细胞数目变化趋势与之类似(P<0.001)。血清皮质酮含量与牙周破坏程度呈正相关关系(P<0.05)。结论:生命早期负性应激可能通过HPA轴增强体液免疫,加剧大鼠实验性牙周炎病变程度。

Effect of Early Life Stress on the Progression of Experimental Periodontitis in Rats.

Objective: To explore the effect of early life stress on the progression of experimental periodontitis in rats. Methods: Twenty male SD rats of 3 weeks old were divided into two groups randomly. One group was suffered the unpredictable chronic mild stress (UCMS) procedure and the other was the control group. After five weeks' UCMS procedure, all rats received the operation of experimental periodontitis (EP). Then the behavioral tests, sucrose preference test, serum corticosterone (CORT) and inflammatory cytokines by ELISA, and HE staining were performed. Results: The UCMS rats showed the depression-like behaviors, including enhanced immobility time in forced swimming test (P<0.01) and lower sucrose preference test (P<0.001). Serum corticosterone, IL-1β and TNF-α was also elevated (P<0.05). In HE staining, rats with EP showed an obvious alveolar bone loss compared with that in the contra-lateral left side. The alveolar bone loss in the UCMS rats was significantly more severe compared with control group (P<0.001). The same tendency was found in the osteoclast numbers (P<0.001). Positive correlation was found between serum corticosterone and severity of EP (P<0.05). Conclusion: Early life stress could aggravate the progression of EP, which might be regulated by HPA axis and humoral immunity.