講演情報
[P-99（E）]Anti-inflammatory Effects of Prostacyclin Analogs on LPS-Stimulated RAW264.7 Macrophages
*Jun He1, Takuya Mino2, Kenji Maekawa2 (1. Graduate School of Removable Prosthodontics and Occlusion, Osaka Dental University, 2. Department of Removable Prosthodontics and Occlusion, Osaka Dental University)
[Objective]
Inflammatory responses in the oral cavity, including periodontitis and peri-implant inflammation, are closely associated with macrophage activation1. Excessive stimulation of macrophages by bacterial components such as lipopolysaccharide (LPS) induces pro-inflammatory cytokine production and oxidative stress, which contribute to tissue destruction and disease progression. Prostacyclin (prostaglandin I2 (PGI2)) is a lipid mediator with reported anti-inflammatory properties, but its effects on macrophage-mediated inflammatory responses relevant to oral diseases remain incompletely understood. The objective of this study was to investigate the effects of PGI2 analogs on LPS-induced inflammatory activation in macrophages, with relevance to oral inflammatory conditions.
[Method]
An in vitro inflammatory model was established using the mouse macrophage-like cell line RAW264.7 stimulated with LPS. After LPS stimulation, cells were treated with PGI2 analogs (epoprostenol, iloprost, and treprostinil). Cell viability was evaluated using the Cell Counting Kit-8 (CCK-8) assay. Inflammatory responses were assessed by measuring mRNA expression levels of interleukin (IL)-6 and IL-1beta using quantitative real-time PCR and cytokine secretion in culture supernatants using enzyme-linked immunosorbent assay (ELISA). Intracellular reactive oxygen species (ROS) production was analyzed using a fluorescent probe-based assay.
[Results and Discussion]
LPS stimulation significantly increased both the expression and secretion of IL-6 and IL-1beta in RAW264.7 cells,confirming successful induction of inflammatory activation. Treatment with PGI2 analogs significantly suppressed both mRNA expression and cytokine secretion of these pro-inflammatory mediators. Cell viability was not suppressed by prostacyclin analog treatment, indicating that the observed anti-inflammatory effects were not attributable to cytotoxicity. In addition, intracellular ROS production induced by LPS stimulation showed a decreasing trend following prostacyclin analog treatment. These findings suggest that PGI2 analogs attenuate macrophage inflammatory activation and oxidative stress responses and may play a regulatory role in oral inflammatory diseases.
[References]
1) Yin L, Li X, Hou J. Macrophages in periodontitis A dynamic shift between tissue destruction and repair. Jpn Dent Sci Rev. 2022;58:336 347.
Inflammatory responses in the oral cavity, including periodontitis and peri-implant inflammation, are closely associated with macrophage activation1. Excessive stimulation of macrophages by bacterial components such as lipopolysaccharide (LPS) induces pro-inflammatory cytokine production and oxidative stress, which contribute to tissue destruction and disease progression. Prostacyclin (prostaglandin I2 (PGI2)) is a lipid mediator with reported anti-inflammatory properties, but its effects on macrophage-mediated inflammatory responses relevant to oral diseases remain incompletely understood. The objective of this study was to investigate the effects of PGI2 analogs on LPS-induced inflammatory activation in macrophages, with relevance to oral inflammatory conditions.
[Method]
An in vitro inflammatory model was established using the mouse macrophage-like cell line RAW264.7 stimulated with LPS. After LPS stimulation, cells were treated with PGI2 analogs (epoprostenol, iloprost, and treprostinil). Cell viability was evaluated using the Cell Counting Kit-8 (CCK-8) assay. Inflammatory responses were assessed by measuring mRNA expression levels of interleukin (IL)-6 and IL-1beta using quantitative real-time PCR and cytokine secretion in culture supernatants using enzyme-linked immunosorbent assay (ELISA). Intracellular reactive oxygen species (ROS) production was analyzed using a fluorescent probe-based assay.
[Results and Discussion]
LPS stimulation significantly increased both the expression and secretion of IL-6 and IL-1beta in RAW264.7 cells,confirming successful induction of inflammatory activation. Treatment with PGI2 analogs significantly suppressed both mRNA expression and cytokine secretion of these pro-inflammatory mediators. Cell viability was not suppressed by prostacyclin analog treatment, indicating that the observed anti-inflammatory effects were not attributable to cytotoxicity. In addition, intracellular ROS production induced by LPS stimulation showed a decreasing trend following prostacyclin analog treatment. These findings suggest that PGI2 analogs attenuate macrophage inflammatory activation and oxidative stress responses and may play a regulatory role in oral inflammatory diseases.
[References]
1) Yin L, Li X, Hou J. Macrophages in periodontitis A dynamic shift between tissue destruction and repair. Jpn Dent Sci Rev. 2022;58:336 347.