Advanced Glycation End Products Increase Inflammation via TLR4 Pathway in Periodontal Ligament Fibroblasts

doi:10.13701/j.cnki.kqyxyj.2020.11.006

Abstract

Abstract: Objective: To investigate the effect of advanced glycation end products (AGEs),a product of diabetes,on the expression of Toll-like receptor 4 (TLR4)-mediated inflammation in periodontal ligament cells (PDLC). Methods: Different doses of AGEs (0,100,300,500 mg/L) were used to treat PDLCs. α-Actin was stained by immunofluorescence staining to detect the cytoskeleton. Western blot was used to detect the effect of AGEs on the expression of TLR4 and the downstream factors IL-1β and TNF-α,as well as the blocking effect of AGEs inhibitor E5564 on TLR4 activation. Immunofluorescence confirmed the activation of IL-1β and TNF-αvia TLR4 pathway by AGEs. Results: AGEs had no effect on the culture and morphology of PDLCs, and no significant effect on the expression of cell structural protein α-Actin. 300 mg/L and 500 mg/L AGEs significantly increased the TLR4 expression compared with the control group,and no statistical difference was found between the 300 mg/L and 500 mg/L doses. The activation of TLR4 caused by AGEs continued to lead to the up-regulation of IL-1β and TNF-α. Western blot and immunofluorescence proved that the addition of TLR4-specific inhibitor E5564 could reverse the activation of IL-1β and TNF-α induced by TLR4 pathway. Conclusion: AGEs have no obvious effect on the morphology of fibroblasts. AGEs may promote the release of inflammatory factors IL-1β and TNF-α from periodontal fibroblasts through the TLR4 pathway.

Key words: AGEs, periodontitis, TLR4, IL-1β, TNF-α

ZHANG Xun, YUAN Caixia, LIN Yuanyuan, TIAN Qunli. Advanced Glycation End Products Increase Inflammation via TLR4 Pathway in Periodontal Ligament Fibroblasts[J]. Journal of Oral Science Research, 2020, 36(11): 1007-1011.

References

[1] Perrone A, Giovino A, Benny J, et al. Advanced Glycation End Products (AGEs): Biochemistry, Signaling, Analytical Methods, and Epigenetic Effects [J]. Oxid Med Cell Longev,2020,2020:3818196.
[2] Katz J, Caudle RM, Bhattacharyya I, et al. Receptor for advanced glycation end product (RAGE) upregulation in human gingival fibroblasts incubated with nornicotine [J]. J Periodontol,2005,76(7):1171-1174.
[3] Lee KJ, Yoo JW, Kim YK, et al. Advanced glycation end products promote triple negative breast cancer cells via ERK and NF-kappaB pathway [J]. Biochem Biophys Res Commun,2018,495(3):2195-2201.
[4] Qin Q, Niu J, Wang Z, et al. Heparanase induced by advanced glycation end products (AGEs) promotes macrophage migration involving RAGE and PI3K/AKT pathway [J]. Cardiovasc Diabetol,2013,12:37.
[5] Qi W, Yang X, Ye N, et al. TLR4 gene in the regulation of periodontitis and its molecular mechanism [J]. Exp Ther Med,2019,18(3):1961-1966.
[6] Korneev KV, Atretkhany KN, Drutskaya MS, et al. TLR-signaling and proinflammatory cytokines as drivers of tumorigenesis [J]. Cytokine,2017,89:127-135.
[7] Takeda K, Akira S. TLR signaling pathways [J]. Semin Immunol,2004,16(1):3-9.
[8] Gurav A, Jadhav V. Periodontitis and risk of diabetes mellitus [J]. J Diabetes,2011,3(1):21-28.
[9] Ren L, Fu Y, Deng Y, et al. Advanced glycation end products inhibit the expression of collagens type I and III by human gingival fibroblasts [J]. J Periodontol,2009,80(7):1166-1173.
[10] Choi AJ, Ryter SW. Inflammasomes: molecular regulation and implications for metabolic and cognitive diseases [J]. Mol Cells,2014,37(6):441-448.
[11] Zhang Z, Liu Q, Liu M, et al. Upregulation of HMGB1-TLR4 inflammatory pathway in focal cortical dysplasia type II [J]. J Neuroinflammation,2018,15(1):27.
[12] Zhu YJ, Wang C, Song G, et al. Toll-like receptor-2 and -4 are associated with hyperlipidemia [J]. Mol Med Rep,2015,12(6):8241-8246.
[13] Lamkanfi M, Dixit VM. Mechanisms and functions of inflammasomes [J]. Cell,2014,157(5):1013-1022.
[14] Chen X, Gao Q, Zhou L, et al. MiR-146a alleviates inflammation of acute gouty arthritis rats through TLR4/MyD88 signal transduction pathway [J]. Eur Rev Med Pharmacol Sci,2019,23(21):9230-9237.
[15] Dinarello CA. Interleukin-1 in the pathogenesis and treatment of inflammatory diseases [J]. Blood,2011,117(14):3720-3732.
[16] Netea MG, Simon A, van de Veerdonk F, et al. IL-1beta processing in host defense: beyond the inflammasomes [J]. PLoS Pathog,2010,6(2):e1000661.
[17] Barbara JA, Van ostade X, Lopez A. Tumour necrosis factor-alpha (TNF-alpha): the good, the bad and potentially very effective [J]. Immunol Cell Biol,1996,74(5):434-443.
[18] Ahmad R, Shihab PK, Thomas R, et al. Increased expression of the interleukin-1 receptor-associated kinase (IRAK)-1 is associated with adipose tissue inflammatory state in obesity [J]. Diabetol Metab Syndr,2015,7:71.