Botanical Extracts from Rosehip (Rosa canina), Willow Bark (Salix alba), and Nettle Leaf (Urtica dioica) Suppress IL-1-Induced NF-κB Activation in Canine Articular Chondrocytes
Figure 9
Effect of botanical extracts on the phosphorylation of IκBα by IL-1β in chondrocytes. Western blot analysis with IL-1β-treated cytoplasmic extracts. Serum-starved chondrocytes ( cells/mL) were pretreated with ALLN (100 μg/mL) for 30 min and cotreated with botanical extracts (each 10 μg/mL) for 4 h and stimulated with IL-1β (10 ng/mL) for the final 1 h. The cytoplasmic extracts were prepared, fractionated on SDS-PAGE, and electroblotted onto nitrocellulose membranes. Western blot analysis was performed using anti-IκBα and p-IκBα antibodies. Treatment of chondrocytes with IL-1β (10 ng/mL) revealed an increase in the phosphorylated IκBα-form in cytoplasmic extracts. In the presence of the inhibitor phosphorylation of IκBα was significantly increased (I–III). Phosphorylation of IκBα was inhibited in chondrocytes cotreated with botanical extracts in the presence or absence of the inhibitor (I–III). Data shown are representative of three independent experiments. Treatments: medium (controls); IL-1β; RC (Rosa canina); SA (Salix alba); UD (Urtica dioica).
