Objectives: To investigate the effect of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) on liver injury induced by periodontitis in rats.
Methods: Twenty-four male Wistar rats were randomly divided into two groups: control group and periodontitis group, twelve per group. In periodontitis group, the periodontitis models were established for the maxillary first molars in rats by means of "wire ligation+vaccinationwith Porphyromonas gingivalis", the control group was inoculated with the equal volume of 2% sodium carboxymethyl cellulose in the same position, for 6 weeks. The probing depth, tooth mobility and sulcus bleeding index were detected. Hematoxylin-eosin (HE) staining was used to observe the pathological changes of liver tissues in rats. The quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) were used to detect the gene and protein expression levels of PGC-1α, nuclear factor erythroid 2-related factor 2 (Nrf2) and mitochondrial transcription factor A (TFAM) in liver tissues of rats.
Results: The probing depth, tooth mobility and sulcus bleeding index in periodontitis group were significantly higher than that in control group. HE staining showed in periodontitis group, hepatic cords ranged disorderly and there were vacuoles in cells and inflammatory cells infiltrated in liver tissues of rats, and there was no obvious abnormality in control group. The qRT-PCR results showed that the mRNA expression levels of Pgc-1α, Nrf2 and Tfam in liver tissues of rats in periodontitis group were lower obviously than that in control group. IHC results showed that the protein expression level of PGC-1α in liver tissues of rats in periodontitis group was decreased significantly than that in control group.
Conclusions: PGC-1α may be involved in the process of periodontitis-induced liver injury in rats.
目的: 初步探究过氧化物酶体增殖物激活受体γ共激活因子-1α（PGC-1α）在牙周炎诱发大鼠肝损伤中的作用。方法: 将24只雄性Wistar大鼠随机分为2组：对照组和牙周炎组，每组各12只。牙周炎组采用结扎丝结扎+接种牙龈卟啉单胞菌的方法建立大鼠上颌第一磨牙牙周炎模型，对照组以等体积2%羧甲基纤维素钠接种同一部位，持续6周。检测大鼠牙周探诊深度、牙齿松动度和龈沟出血指数。苏木精-伊红（HE）染色观察大鼠肝组织病理变化情况，实时荧光定量聚合酶链反应（qRT-PCR）及免疫组织化学方法分别检测大鼠肝组织中PGC-1α、核因子E2-相关因子2（Nrf2）及线粒体转录因子A（TFAM）基因及蛋白表达水平。结果: 牙周炎组牙周探诊深度、牙齿松动度和龈沟出血指数数值显著高于对照组。HE结果显示：牙周炎组大鼠肝组织肝索排列紊乱，可见空泡性变及炎症细胞浸润，对照组无明显异常。qRT-PCR结果显示：牙周炎组大鼠肝组织中Pgc-1α、Nrf2和Tfam的mRNA表达水平明显低于对照组。免疫组织化学结果显示：牙周炎组大鼠肝组织中PGC-1α蛋白表达水平较对照组明显降低。结论: PGC-1α可能参与牙周炎诱发大鼠肝损伤过程。.
Keywords: liver injury; periodontitis; peroxisome proliferator-activated receptor-γ coactivator-1α.