Exploration Of The Level Of The Endoplasmic Reticulum Stress-response In Different Periodontal Condition

BackgroundNumerous studies show that apoptosis is involved in the pathophysiology of periodontal disease, while the pathways associated with apoptosis are divided into mitochondrial pathway, death receptor pathway, granzyme B pathway and endoplasmic reticulum stress(ERS) pathway which is the latest findings. ERS is a series of cellular responses resulting from stress-induced when tissue and cell under unfavorable survival environment, its purpose is to maintain cellular homeostasis through non-protection of the unfolded protein response(UPR). UPR can play a crucial role in the process of protecting cell by slowing down the speed of generating protein, strengthening the function of folding protein the unfolded protein and degradating unfolded protein. Apoptosis will happen when environment strss persists or intensity is too large which is out of cell self-regulation ability, cell overall status change from promoting survival to promoting apoptosis.Gingival as the only periodontal tissue that exposed to oral environment and as various types of periodontal disease initiation site, and it has important clinical significance to explore what happened to it during the occurrence of periodontal disease. When the periodontal disease happened, pathogenic components of periodontal pathogens and toxins produced by pathogens will makes an exception of the level of varies adhesive protein, such as epithelial cadherin protein-1, etc. which can damage the interconnection between epithelial cells and increase the permeability of epithelial cells, leading to plaque microorganisms can easier through the physical barrier of the gingival epithelium to deep tissue, thus promoting the development of periodontitis. In addition, a variety of immune factors secreted by gingival epithelium cells such as the antibacterial peptide LL-37, the human ?-defensin can defense plaque and other microbial's invasion and play an important role in preventing the process of periodontal disease.At present, there are articles reported that ERS was involved in the pathogenesis of chronic periodontitis and the level of GRP78 and CHOP was ascent under the condition or chronic periodontitis, but differences of the level of ERS under health, chronic gingivitis, chronic periodontitis and aggressive periodontitis yet reported.Objective:To preliminary explore the level of the endoplasmic reticulum stress-response in health, chronic gingivitis, chronic periodontitis and aggressive periodontitis gingival tissue.Methods:Explore the differences of expression of GRP78, PERK, ATF4 and CHOP in gingival epithelium under different condition:Collect gingival of healthy, chronic gingivitis, chronic periodontitis and aggressive periodontitis to compare the expression of GRP78, PERK, ATF4 and CHOP by immunohistochemically staining, Real-time PCR and Western blot. Results: 1. Immunohistochemistry results:The rate of positive cell expression of GRP78 and CHOP is aggressive periodontitis >chronic periodontitis>chronic gingivitis >healthy gingival, the difference is of statistically significant(P<0.05). The rate of positive cell expression of PERK and ATF4 is chronic periodontitis>chronic gingivitis >healthy gingival and aggressive periodontitis, the difference is of statistically significant(P<0.05), the rate of positive cell expression of PERK and ATF4 in healthy gingival and aggressive periodontitis is of no statistically significant(P>0.05). 2. Real-time PCR results:The rate of mRNA expression of GRP78 and CHOP is aggressive periodontitis >chronic periodontitis > chronic gingivitis > healthy gingival, the difference is of statistically significant(P<0.05). The rate of mRNA expression of PERK is chronic periodontitis>chronic gingivitis >healthy gingival and aggressive periodontitis, the difference is of statistically significant(P<0.05), the rate of mRNA expression of PERK in healthy gingival and aggressive periodontitis is of no statistically significant(P>0.05). The rate of mRNA expression of ATF4 under the status of chronic periodontitis and chronic gingivitis are higher than healthy gingival and aggressive periodontitis, the difference is of statistically significant(P<0.05), the rate of mRNA expression of PERK in healthy gingival and aggressive periodontitis, chronic periodontitis and chronic gingivitis are of no statistically significant(P>0.05) 3. Western blot results:The rate of protein expression of GRP78 and CHOP is aggressive periodontitis >chronic periodontitis > chronic gingivitis > healthy gingival, the difference is of statistically significant(P<0.05). The rate of protein expression of PERK and ATF4 is chronic periodontitis>chronic gingivitis >healthy gingival and aggressive periodontitis, the difference is of statistically significant(P<0.05), the rate of protein expression of PERK and ATF4 in healthy gingival and aggressive periodontitis is of no statistically significant(P>0.05). Conclusions:1.There are differences in the level of ERS in gingival tissues under different conditions, and manifest as aggressive periodontitis >chronic periodontitis>chronic gingivitis >healthy gingival.2.The level of PERK pathway is chronic periodontitis>chronic gingivitis >healthy gingival and aggressive periodontitis.3.Endoplasmic reticulum stress levels will elevate in patients with aggressive periodontitis and chronic periodontitis gingiva, but the pathway are different between the two.