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Context: Verbascum phlomoides L. (Scrophulariaceae) (mullein) used in the European folk medicine due to its anti-inflammatory and soothing action on the respiratory tract is thoroughly documented in handbooks and scientific literature. Nevertheless, information regarding the influence of the polyphenol content on pharmacological activity is scarce., Objective: This study explored the antioxidant and anti-inflammatory potential of V. phlomoides polyphenol-rich extract., Materials and Methods: Dried mullein flowers (200 g) were subjected to water extraction (60 °C, 2 h, herb/solvent ratio = 1/10 m/v) and further to n-butanol partition. Total phenolics were spectrophotometrically determined and specific compounds were evaluated by HPLC. The antioxidant activity was assessed by the 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) assay. The anti-inflammatory potential of the extract (50-200 μg/mL) was evaluated in vitro by ELISA measurement of ICAM-1 expression in TNF-α-stimulated endothelial cells and in vivo by the rat paw edema assay., Results: The mullein extract contained 4.18% total polyphenols expressed as gallic acid. The main components identified by HPLC were: rosmarinic acid (14.93 mg/g), caffeic acid (39.96 mg/g), ferulic acid (29.61 mg/g) and quercetin (17.29 mg/g). Acteoside was not detected; aucubin was detected in traces (0.028 mg/g). Depending on concentration, the extract exerted scavenging activity on DPPH radical (EC50 7.09 mg/mL), significantly inhibited TNF-α-induced ICAM-1 expression by 55-58.8% on human umbilical vein endothelial cells at 100 and 200 μg/mL, but failed to reduce egg-white-induced rat paw edema., Discussion and Conclusion: Mullein polyphenols play an important role in exerting the antioxidant effect but have a weak influence on anti-inflammatory activity that is correlated, probably, to a higher content of iridoids and phenylethanoids.

Most disease—both acute and chronic—results from inflammation, and reactive oxygen species (ROS) are considered some of the strongest stimuli of inflammation. Many studies reported the traditional use of herbal species for treating inflammation, especially when ROS are involved. The present study aims to demonstrate the antioxidant–anti-inflammatory effects of a patented preparation based on Populus nigra and Rosmarinus officinalis extracts and to highlight its applicative potential; the formula was characterized by HPTLC and HPLC and in-vitro studies were conducted on TNF-α-stimulated HUVECs. The antioxidant activity of the formula was determined by DPPH assay and the phosphomolybdenum method; to assess in-vivo anti-inflammatory activity, a rat paw edema model was used; the formula contains high amounts of polyphenols. It exhibited scavenging activity of 50–85% at 1–10 mg/mL, it inhibited nitrite production and ICAM-1 expression in TNF-α-stimulated endothelial cell cultures dose-dependently, at a maximum of 58.7% at the maximum dose administered and exerted an obvious anti-inflammatory effect in vivo, settling early and decreasing at 180 min; a new herbal bioactive product was presented with promising therapeutic potential that can be an adjunct to conventional therapies for diseases based on oxidative stress and inflammation. [ABSTRACT FROM AUTHOR]