Endoplasmic Reticulum Stress Response in Periodontal Disease

Overview

Periodontal disease causes inflammation and damage to the tissues that support the teeth. This study looks at whether stress inside gum cells contributes to this damage. Cells have a stress response system that helps them deal with damaged or misfolded proteins. This study measured several markers of this cell stress response (called GRP78, PERK, IRE1, ATF6, MANF, CRELD2) along with a marker of inflammation (TNF-α). These were measured in fluid collected from around the teeth and in small samples of gum tissue. Researchers compared 72 healthy adults who did not smoke, divided into three equal groups: people with healthy gums, people with mild gum inflammation (gingivitis), and people with a more advanced form of gum disease (periodontitis). The results showed that markers of cell stress were higher in people with periodontitis compared to the other two groups, both in the fluid around the teeth and in the gum tissue itself. This suggests that cell stress inside gum tissue may play a role in the inflammation and tissue breakdown seen in periodontitis. These findings may help researchers better understand what drives gum disease and could guide future work on new ways to detect or treat it.

Periodontal disease will range from gingivitis, a mild and reversible gum inflammation, to periodontitis, a more advanced form that will cause irreversible destruction of the bone and tissue supporting the teeth and may lead to tooth loss if left untreated. A cellular process known as endoplasmic reticulum (ER) stress will be increasingly linked to chronic inflammatory diseases. When cells are exposed to stress, misfolded proteins will accumulate inside the endoplasmic reticulum, and cells will activate a protective mechanism called the unfolded protein response (UPR) to restore normal function. The UPR will operate through three main pathways controlled by the proteins PERK, IRE1, and ATF6. This study will investigate whether markers of ER stress and the UPR, GRP78, PERK, IRE1, ATF6, MANF, and CRELD2 along with the inflammatory marker TNF-α, will be altered in individuals with periodontal disease, and whether these changes will be associated with inflammation severity and tissue destruction. The study will include 72 systemically healthy, non-smoking adults, divided into three equal groups of 24: periodontally healthy individuals, individuals with gingivitis, and individuals with stage III grade B periodontitis. From each participant, gingival crevicular fluid and gingival tissue samples will be collected. Protein levels will be measured using ELISA, and gene expression levels will be assessed using RT-qPCR. In the periodontitis group, total amounts of GRP78, IRE1, PERK, MANF, and CRELD2 in gingival crevicular fluid are expected to be significantly higher, while their concentrations are expected to be lower. Protein levels of IRE1, PERK, MANF, and CRELD2 in gingival tissue, along with gene expression levels of all markers studied, are expected to be significantly elevated. ATF6 is expected to show a distinct pattern, with decreased fluid levels but increased tissue gene expression. These findings are expected to show that ER stress and UPR pathways will be more active in the gingival tissue of individuals with periodontitis, correlating with inflammation and tissue destruction. This will help researchers identify new biological markers for periodontal disease and support future research into treatments targeting cellular stress pathways.