title: High glucose induces inflammatory cytokine through protein kinase C-induced toll-like receptor 2 pathway in gingival fibroblasts.
abstract: Toll-like receptors (TLRs) play a key role in innate immune response and inflammation, especially in periodontitis. Meanwhile, hyperglycemia can induce inflammation in diabetes complications. However, the activity of TLRs in periodontitis complicated with hyperglycemia is still unclear. In the present study, high glucose (25 mmol/l) significantly induced TLR2 expression in gingival fibroblasts (p<0.05). Also, high glucose increased nuclear factor kappa B (NF-κB) p65 nuclear activity, tumor necrosis factor-α (TNF-α) and interleukin-lβ (IL-1β) levels. Protein kinase C (PKC)-α and δ knockdown with siRNA significantly decreased TLR2 and NF-κB p65 expression (p<0.05), whereas inhibition of PKC-β had no effect on TLR2 and NF-κB p65 under high glucose (p<0.05). Additional studies revealed that TLR2 knockdown significantly abrogated high-glucose-induced NF-κB expression and inflammatory cytokine secretion. Collectively, these data suggest that high glucose stimulates TNF-α and IL-1β secretion via inducing TLR2 through PKC-α and PKC-δ in human gingival fibroblasts.
authors.affiliation: School of Dentistry, Tianjin Medical University, 12 Qi Xiang Tai Street, Heping District, Tianjin 300070, China. jiangshaoyun@yahoo.com
authors.forename: Shao-Yun
authors.initials: SY
authors.lastname: Jiang
authors.forename: Cong-Cong
authors.initials: CC
authors.lastname: Wei
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Shang
authors.forename: Qi
authors.initials: Q
authors.lastname: Lian
authors.forename: Chen-Xuan
authors.initials: CX
authors.lastname: Wu
authors.forename: Jia-Yin
authors.initials: JY
authors.lastname: Deng
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D005347:Fibroblasts / Q000187:drug effects / Q000276:immunology; D055785:Gene Knockdown Techniques; D005881:Gingiva / Q000187:drug effects / Q000276:immunology*; D005947:Glucose / Q000494:pharmacology; D006801:Humans; D006943:Hyperglycemia / Q000276:immunology*; D053583:Interleukin-1beta / Q000096:biosynthesis*; D011493:Protein Kinase C / Q000378:metabolism*; D064546:Protein Kinase C beta; D051571:Protein Kinase C-alpha / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051195:Toll-Like Receptor 2 / Q000096:biosynthesis* / Q000235:genetics; D051996:Transcription Factor RelA / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D053583:Interleukin-1beta; D012333:RNA, Messenger; D051195:Toll-Like Receptor 2; D051996:Transcription Factor RelA; D014409:Tumor Necrosis Factor-alpha; D011493:Protein Kinase C; D064546:Protein Kinase C beta; D051571:Protein Kinase C-alpha; D005947:Glucose