Department of Oral Biology, University Clinic of Dentistry, Medical University of Vienna, 1090 Vienna, Austria.
Department of Dentistry, Federal University of Santa Catarina, Florianopolis 88040-900, Brazil.
Int J Mol Sci. 2022 Jul 27;23(15):8306. doi: 10.3390/ijms23158306.
Pyroptosis is a catabolic process relevant to periodontal disorders for which interleukin-1β (IL-1β) inflammation is central to the pathophysiology of the disease. Despite platelet-rich fibrin (PRF) anti-inflammatory properties and its application to support periodontal regeneration, the capacity of PRF to modulate pyroptosis, specifically the production and release of IL-1β, remains unknown. The question arises whether PRF could regulate IL-1β release from macrophages in vitro.
To answer this question, RAW 264.7 macrophages and primary macrophages obtained from murine bone marrow were primed with PRF before being challenged by lipopolysaccharide (LPS). Cells were then analysed for the pyroptosis signalling components by gene expression analyses and IL-1β secretion at the protein level. The release of mitochondrial reactive oxygen species (ROS) was also detected.
PRF lowered the LPS-induced expression of IL-1β and NLRP3 inflammasome, caspase-11 and IL-18 in primary macrophages, and IL-1β and caspase-11 in RAW 264.7 cells. Additionally, PRF diminished the secretion of IL-1β at the protein level in LPS-induced RAW 264.7 cells. This was shown through immunoassays performed with the supernatant and further confirmed by analysing the lysates of permeabilised cells. Furthermore, PRF reduced the ROS release provoked by LPS in RAW 264.7 cells. Finally, to enhance IL-1β release from the LPS-primed macrophages, we introduced a second signal with adenosine triphosphate (ATP). In this setting, PRF significantly reduced IL-1β release in RAW 264.7 cells and a trend to diminish IL-1β release in primary macrophages.
These findings suggest that PRF can reduce IL-1β release and, at least in part, inhibit pyroptosis-related factors in LPS-challenged macrophages.
细胞焦亡是一种与牙周病相关的分解代谢过程，其中白细胞介素-1β（IL-1β）炎症是疾病病理生理学的核心。尽管富含血小板的纤维蛋白（PRF）具有抗炎特性，并被应用于支持牙周组织再生，但 PRF 调节细胞焦亡的能力，特别是调节 IL-1β 的产生和释放，尚不清楚。问题是 PRF 是否可以调节体外巨噬细胞中 IL-1β 的释放。
为了回答这个问题，用 PRF 预处理 RAW 264.7 巨噬细胞和来自鼠骨髓的原代巨噬细胞，然后用脂多糖（LPS）刺激。通过基因表达分析和蛋白质水平的 IL-1β 分泌来分析细胞焦亡信号成分。还检测了线粒体活性氧（ROS）的释放。
PRF 降低了 LPS 诱导的原代巨噬细胞中 IL-1β 和 NLRP3 炎性体、半胱天冬酶-11 和 IL-18 的表达，以及 RAW 264.7 细胞中 IL-1β 和半胱天冬酶-11 的表达。此外，PRF 减少了 LPS 诱导的 RAW 264.7 细胞中 IL-1β 的蛋白分泌。这通过上清液的免疫测定法进行，并通过分析透化细胞的裂解物进一步证实。此外，PRF 减少了 LPS 诱导的 RAW 264.7 细胞中 ROS 的释放。最后，为了增强 LPS 刺激的巨噬细胞中 IL-1β 的释放，我们用三磷酸腺苷（ATP）引入第二个信号。在这种情况下，PRF 显著减少了 RAW 264.7 细胞中 IL-1β 的释放，并在原代巨噬细胞中显示出减少 IL-1β 释放的趋势。
这些发现表明，PRF 可以减少 LPS 刺激的巨噬细胞中 IL-1β 的释放，并在一定程度上抑制与细胞焦亡相关的因素。
