Delphinidin Inhibits Il-1 Beta-induced Activation Of Nf-kappa B By Modulating The Phosphorylation Of Irak-1(ser376) In Human Articular Chondrocytes
chondrocytes; COX-2; delphinidin; down-regulation; factor-alpha; gene-expression; human osteoarthritis chondrocytes; IL-1 beta; in-vitro; interleukin-1; kinase; nf-kappa-b; osteoarthritis; oxidative stress; PGE(2); rheumatoid-arthritis; Rheumatology; tumor-necrosis-factor
Objective. In OA, there is enhanced expression of pro-inflammatory cytokines such as IL-1 beta in the affected joint. Delphinidin, an anthocyanidin found in pigmented fruits and vegetables, has been shown to possess anti-inflammatory and antioxidant properties. In the present study we determined whether delphinidin would inhibit the IL-1 beta-induced activation of NF-kappa B in human chondrocytes and determined the mechanism of its action. Methods. PGE(2) levels and activation of NF-kappa B p65 in human OA chondrocytes were determined by ELISA-based assays. Protein expression of cyclo-oxygenase-2 (COX-2) and phosphorylation of kinases was determined by western immunoblotting. Expression level of mRNAs was determined by TaqMan assays. Results. Delphinidin inhibited IL-1 beta-induced expression of COX-2 and production of PGE(2) in human chondrocytes. Delphinidin also inhibited IL-1 beta-mediated phosphorylation of IL-1 receptor-associated kinase-1(Ser376), phosphorylation of IKK alpha/beta, expression of IKK beta, degradation of I kappa B alpha, and activation and nuclear translocation of NF-kappa B/p65. Phosphorylation of TGF-beta-activated kinase 1 was not observed but NF-kappa B-inducing kinase (NIK) was phosphorylated and phosphorylation of NIK was blocked by delphinidin in IL-1 beta-treated human chondrocytes. Conclusion. These data identify delphinidin as a novel inhibitor of IL-1 beta-induced production of cartilage-degrading molecule PGE(2) via inhibition of COX-2 expression and provide new insight into the mechanism of its action. Our results also identify inhibition of IRAK1(Ser376) phosphorylation by delphinidin in IL-1 beta-induced activation of NF-kappa B in human chondrocytes. Given the important role played by IL-1 beta-induced NF-kappa B activation, COX-2 expression and PGE(2) production in OA, our results may have important implications for the development of novel therapeutic strategies for the prevention/treatment of OA.
Haseeb A; Chen D X; Haqqi T M
Rheumatology
2013
2013-06
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1093/rheumatology/kes363" target="_blank" rel="noreferrer noopener">10.1093/rheumatology/kes363</a>
Inhibition of cartilage degradation and suppression of PGE2 and MMPs expression by pomegranate fruit extract in a model of posttraumatic osteoarthritis.
*Phytotherapy; *Punicaceae; ACLT; Animal; Animals; Anterior Cruciate Ligament/drug effects/metabolism/pathology; Apoptosis; Cartilage/cytology/*drug effects/metabolism/pathology; Chondrocytes/drug effects/metabolism/pathology; Collagen Type II/genetics/metabolism; Dinoprostone/*metabolism; Disease Models; Disease Progression; Female; Fruit; Interleukins/metabolism; Joints/cytology/*drug effects/metabolism/pathology; Male; Messenger/metabolism; Metalloproteases/genetics/*metabolism; Mitogen-Activated Protein Kinases/metabolism; MMPs; NF-kappa B/metabolism; Osteoarthritis; Osteoarthritis/*drug therapy/etiology/metabolism/pathology; PGE(2); Plant Extracts/pharmacology/therapeutic use; Pomegranate; Rabbit; Rabbits; RNA; Synovial Fluid/metabolism
OBJECTIVE: Osteoarthritis (OA) is characterized by cartilage degradation in the affected joints. Pomegranate fruit extract (PFE) inhibits cartilage degradation in vitro. The aim of this study was to determine whether oral consumption of PFE inhibits disease progression in rabbits with surgically induced OA. METHODS: OA was surgically induced in the tibiofemoral joints of adult New Zealand White rabbits. In one group, animals were fed PFE in water for 8 wk postsurgery. In the second group, animals were fed PFE for 2 wk before surgery and for 8 wk postsurgery. Histologic assessment and scoring of the cartilage was per Osteoarthritis Research Society International guidelines. Gene expression and matrix metalloproteinases (MMP) activity were determined using quantitative reverse transcriptase polymerase chain reaction and fluorometric assay, respectively. Interleukin (IL)-1 beta, MMP-13, IL-6, prostaglandin (PG)E2, and type II collagen (COL2A1) levels in synovial fluid/plasma/culture media were quantified using enzyme-linked immunosorbent assay. Expression of active caspase-3 and poly (ADP-ribose) polymerase p85 was determined by immunohistochemistry. Effect of PFE and inhibitors of MMP-13, mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappaB was studied in IL-1 beta-stimulated rabbit articular chondrocytes. RESULTS: Safranin-O-staining and chondrocyte cluster formation was significantly reduced in the anterior cruciate ligament transaction plus PFE fed groups. Expression of MMP-3, MMP-9, and MMP-13 mRNA was higher in the cartilage of rabbits given water alone but was significantly lower in the animals fed PFE. PFE-fed rabbits had lower IL-6,
Akhtar Nahid; Khan Nazir M; Ashruf Omer S; Haqqi Tariq M
Nutrition (Burbank, Los Angeles County, Calif.)
2017
2017-01
Article information provided for research and reference use only. All rights are retained by the journal listed under publisher and/or the creator(s).
<a href="http://doi.org/10.1016/j.nut.2016.08.004" target="_blank" rel="noreferrer noopener">10.1016/j.nut.2016.08.004</a>