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 3
Effects of botanical extracts on IL-1β-induced downregulation of extracellular matrix and signaling proteins in chondrocytes. Serum-starved chondrocytes ( cells/mL) were cultured for 24 h and then treated with 10 ng/mL IL-1β for 48 h, botanical extracts (each 10 μg/ml) for 72 h, or pretreated with botanical extracts (10 μg/mL each) for 24 h and then cotreated with 10 ng/mL IL-1β for 48 h or left untreated and evaluated after 72 h. Western blot analysis revealed down-regulation of collagen type II (I), CSPG (II) and β1-integrin (III) in chondrocytes by IL-1β. Co-treatment of chondrocytes preincubated with botanical extracts and IL-1β suppressed the IL-1β-induced inhibition of collagen type II, CSPG and β1-integrin (I, II, III). In untreated and in botanical extracts alone treated control cultures, expression of collagen type II, CSPG and β1-integrin were equally strong in chondrocytes (I–III). Expression of β-actin was not affected by IL-1β and/or botanical extracts (IV). Data shown are representative of three independent experiments. Treatments: C (untreated control); IL-1β; RC (Rosa canina); SA (Salix alba); UD (Urtica dioica).
