Student Research Committee, Shiraz University of Medical Sciences, Shiraz, Iran.
Oral and Dental Disease Research Center, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
BMC Oral Health. 2023 Jul 13;23(1):481. doi: 10.1186/s12903-023-03183-9.
The current literature suggests the significant role of foam cells in the initiation of atherosclerosis through the formation of a necrotic core in atherosclerotic plaques. Moreover, an important periodontal pathogen called Porphyromonas gingivalis (P. gingivalis) is indicated to play a significant role in this regard. Thus, the aim of this systematic review was to comprehensively study the pathways by which P. gingivalis as a prominent bacterial species in periodontal disease, can induce foam cells that would initiate the process of atherosclerosis formation.
An electronic search was undertaken in three databases (Pubmed, Scopus, and Web of Science) to identify the studies published from January 2000 until March 2023. The risk of bias in each study was also assessed using the QUIN risk of bias assessment tool.
After the completion of the screening process, 11 in-vitro studies met the inclusion criteria and were included for further assessments. Nine of these studies represented a medium risk of bias, while the other two had a high risk of bias. All of the studies have reported that P. gingivalis can significantly induce foam cell formation by infecting the macrophages and induction of oxidized low-density lipoprotein (oxLDL) uptake. This process is activated through various mediators and pathways. The most important factors in this regard are the lipopolysaccharide of P. gingivalis and its outer membrane vesicles, as well as the changes in the expression rate of transmembrane lipid transportation channels, including transient receptor potential channel of the vanilloid subfamily 4 (TRPV4), lysosomal integral protein 2 (LIMP2), CD36, etc. The identified molecular pathways involved in this process include but are not limited to NF-κB, ERK1/2, p65.
Based on the results of this study, it can be concluded that P. gingivalis can effectively promote foam cell formation through various pathogenic elements and this bacterial species can affect the expression rate of various genes and the function of specific receptors in the cellular and lysosomal membranes. However, due to the moderate to high level of risk of bias among the studies, further studies are required in this regard.
目前的文献表明，泡沫细胞在动脉粥样硬化斑块中形成坏死核心，在动脉粥样硬化的发生中起重要作用。此外，一种重要的牙周病原体牙龈卟啉单胞菌（P. gingivalis）被认为在这方面起着重要作用。因此，本系统评价的目的是全面研究牙周病中突出的细菌物种牙龈卟啉单胞菌如何诱导泡沫细胞，从而启动动脉粥样硬化形成过程。
在三个数据库（Pubmed、Scopus 和 Web of Science）中进行电子检索，以确定 2000 年 1 月至 2023 年 3 月期间发表的研究。还使用 QUIN 偏倚风险评估工具评估了每项研究的偏倚风险。
在完成筛选过程后，11 项体外研究符合纳入标准，并纳入进一步评估。其中 9 项研究为中度偏倚风险，另外 2 项研究为高度偏倚风险。所有研究均表明，牙龈卟啉单胞菌通过感染巨噬细胞和诱导氧化型低密度脂蛋白（oxLDL）摄取，可显著诱导泡沫细胞形成。这一过程是通过各种介质和途径激活的。在这方面最重要的因素是牙龈卟啉单胞菌的脂多糖及其外膜囊泡，以及跨膜脂质转运通道的表达率变化，包括香草素亚家族 4（TRPV4）瞬时受体电位通道、溶酶体整合蛋白 2（LIMP2）、CD36 等。参与这一过程的确定分子途径包括但不限于 NF-κB、ERK1/2、p65。
根据本研究的结果，可以得出结论，牙龈卟啉单胞菌可以通过各种致病因素有效促进泡沫细胞形成，这种细菌可以影响细胞和溶酶体膜上各种基因的表达率和特定受体的功能。然而，由于研究中存在中度至高度偏倚风险，因此需要在这方面进行进一步的研究。
