IADR Abstract Archives
“Inflammageing” on Human Oral Cells: Correlation With Age-Related Diseases?
Objectives: Tissue inflammation has the potential to provoke cellular senescence, a process known as “inflammageing”, driving living cells to a state of permanent cell cycle arrest due to chronic antigenic irritation. This in vitro study aimed to shed light on the mechanisms of “inflammageing” on human oral cells.
Methods: Primary cultures of human gingival fibroblasts (hGFs) were exposed to pro-inflammatory stimuli, including lipopolysaccharide (LPS), Tumor Necrosis Factor-alpha (TNFa), and gingival crevicular fluid (GCF) collected from active periodontal pockets of systemically healthy patients. Inflammageing was studied through two experimental models, employing either “aged” hGFs after prolonged passaging (p.10) that were exposed to the pro-inflammatory stimuli or young hGFs long-term exposed to the above stimuli from early- (p.1) to late- (p.10) passaging. Cells were evaluated for the expression of beta-galactosidase (histochemical staining) expression, senescence-associated genes (qPCR analysis), and for Senescence Associated Secretory Phenotype (SASP) biomarkers (proteomic quantitation analysis followed by bioinformatics analysis).
Results: Significant increase (p<0.05) of beta-galactosidase positive cells was observed after exposure to each of the pro-inflammatory stimuli. The senescence-associated genes profile included upregulation for CCND1 and downregulation for C2CD5, SUSD6 and STAG1, which is typical for cellular senescence. Overall, pro-inflammatory licensing of late-passage cells caused more pronounced effects compared to long-term exposure of early-passage cells to the stimuli. The proteomic analysis showed induction of SASP evidenced by upregulation of several pro-inflammatory proteins (e.g. IL-6, IL-10, IL-16, IP-10, MCP-1, MCP-2, M-CSF, MIP-1a, MIP-1b, TNFb, sTNF-RI, sTNF-RII, TIMP-2) implicated in cellular aging and immune responses. The smallest impact on SASP was provoked by LPS and the most pronounced by GCF.
Conclusions: This study demonstrated that long-term exposure of hGFs to various pro-inflammatory signals induced and accelerated cellular senescence with the most significant effects noted for the aged cells.
Methods: Primary cultures of human gingival fibroblasts (hGFs) were exposed to pro-inflammatory stimuli, including lipopolysaccharide (LPS), Tumor Necrosis Factor-alpha (TNFa), and gingival crevicular fluid (GCF) collected from active periodontal pockets of systemically healthy patients. Inflammageing was studied through two experimental models, employing either “aged” hGFs after prolonged passaging (p.10) that were exposed to the pro-inflammatory stimuli or young hGFs long-term exposed to the above stimuli from early- (p.1) to late- (p.10) passaging. Cells were evaluated for the expression of beta-galactosidase (histochemical staining) expression, senescence-associated genes (qPCR analysis), and for Senescence Associated Secretory Phenotype (SASP) biomarkers (proteomic quantitation analysis followed by bioinformatics analysis).
Results: Significant increase (p<0.05) of beta-galactosidase positive cells was observed after exposure to each of the pro-inflammatory stimuli. The senescence-associated genes profile included upregulation for CCND1 and downregulation for C2CD5, SUSD6 and STAG1, which is typical for cellular senescence. Overall, pro-inflammatory licensing of late-passage cells caused more pronounced effects compared to long-term exposure of early-passage cells to the stimuli. The proteomic analysis showed induction of SASP evidenced by upregulation of several pro-inflammatory proteins (e.g. IL-6, IL-10, IL-16, IP-10, MCP-1, MCP-2, M-CSF, MIP-1a, MIP-1b, TNFb, sTNF-RI, sTNF-RII, TIMP-2) implicated in cellular aging and immune responses. The smallest impact on SASP was provoked by LPS and the most pronounced by GCF.
Conclusions: This study demonstrated that long-term exposure of hGFs to various pro-inflammatory signals induced and accelerated cellular senescence with the most significant effects noted for the aged cells.