Protective effect of resveratrol against IL-1β-induced inflammatory response on human osteoarthritic chondrocytes partly via the TLR4/MyD88/NF-κB signaling pathway: an "in vitro study".
Resveratrol is a natural polyphenolic compound that prevents inflammation in chondrocytes and animal models of osteoarthritis (OA) via yet to be defined mechanisms. The purpose of this study was to determine whether the protective effect of resveratrol on IL-1β-induced human articular chondrocytes was associated with the TLR4/MyD88/NF-кB signaling pathway by incubating human articular chondrocytes (harvested from osteoarthritis patients) with IL-1β before treatment with resveratrol. Cell viability was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and TNFα levels in culture supernatants were measured by ELISA(Enzymelinked immunosorbent assay). The levels of TLR4 and its downstream signaling targets (MyD88 and TRAF6) and IL-1β were assessed by measuring the levels of mRNA and protein expression by real-time RT-PCR and western blot analysis, respectively, in addition to assessing NF-кB activation. In addition, TLR4 siRNA was used to block TLR4 expression in chondrocytes further demonstrating that resveratrol prevented IL-1β-mediated inflammation by TLR4 inhibition. We found that resveratrol prevented IL-1β-induced reduction in cell viability. Stimulation of chondrocytes with IL-1β caused a significant up-regulation of TLR4 and its downstream targets MyD88 and TRAF6 resulting in NF-кB activation associated with the synthesis of IL-1β and TNFα. These IL-1β-induced inflammatory responses were all effectively reversed by resveratrol. Furthermore, activation of NF-кB in chondrocytes treated with TLR4 siRNA was significantly attenuated, but not abolished, and exposure to resveratrol further reduced NF-кB translocation. These data suggested that resveratrol prevented IL-1β-induced inflammation in human articular chondrocytes at least in part by inhibiting the TLR4/MyD88/NF-кB signaling pathway suggesting that resveratrol has the potential to be used as a nutritional supplement to counteract OA symptoms.
Department of Nutrition and Food Hygiene, School of Public Health, China Medical University, No. 92 Beier Road, Heping District, Shenyang 110001, Liaoning, China. liuli@mail.cmu.edu.cn.
Li
L
Liu
Department of Orthopedics, Shengjing Hospital, China Medical University, No. 36 Sanhao Street, Sanhao District, Shenyang 110004, Liaoning, China. guhailun_@163.com.
Hailun
H
Gu
Department of Nutrition and Food Hygiene, School of Public Health, China Medical University, No. 92 Beier Road, Heping District, Shenyang 110001, Liaoning, China.
Huimin
H
Liu
Department of Nutrition and Food Hygiene, School of Public Health, China Medical University, No. 92 Beier Road, Heping District, Shenyang 110001, Liaoning, China. jylaaa@126.com.
Yongliang
Y
Jiao
Department of Nutrition and Food Hygiene, School of Public Health, China Medical University, No. 92 Beier Road, Heping District, Shenyang 110001, Liaoning, China. lkylky@163.com.
Keyu
K
Li
Department of Nutrition and Food Hygiene, School of Public Health, China Medical University, No. 92 Beier Road, Heping District, Shenyang 110001, Liaoning, China. zhao_yue@163.com.
Yue
Y
Zhao
Department of Nutrition and Food Hygiene, School of Public Health, China Medical University, No. 92 Beier Road, Heping District, Shenyang 110001, Liaoning, China. anli@mail.cmu.edu.cn.
Li
L
An
Department of Nutrition and Food Hygiene, School of Public Health, China Medical University, No. 92 Beier Road, Heping District, Shenyang 110001, Liaoning, China. yangjun@mail.cmu.edu.cn.
Jun
J
Yang
D000368:Aged; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D053583:Interleukin-1beta / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology*; D008875:Middle Aged; D053594:Myeloid Differentiation Factor 88 / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D000077185:Resveratrol; D015398:Signal Transduction / Q000187:drug effects*; D013267:Stilbenes / Q000494:pharmacology*; D048029:TNF Receptor-Associated Factor 6 / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
D053583:Interleukin-1beta; D053594:Myeloid Differentiation Factor 88; D016328:NF-kappa B; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D013267:Stilbenes; D048029:TNF Receptor-Associated Factor 6; D051197:Toll-Like Receptor 4; D014409:Tumor Necrosis Factor-alpha; D000077185:Resveratrol