Subscribe to RSS
Inhibition of xanthine oxidase activity by Filipendula species
Filipendula species, in particular F. ulmaria (meadowsweet), have traditionally been used for the treatment of gout [1,2]. One of the primary targets for the treatment of gout is xanthine oxidase (XO), an enzyme responsible for the oxidation of hypoxanthine and xanthine to uric acid . The scope of this research was to analyze the XO-inhibitory activity of F. ulmaria and a related species, F. vulgaris, in order to rationalize the traditional use of these plants. Extracts were tested for their capacity to inhibit XO by spectrophotometrical determination of the rate of uric acid formation. The anti-gout drug allopurinol and its active metabolite oxypurinol were used as positive controls. Methanolic extracts of the flowers of F. ulmaria and F. vulgaris were demonstrated to have high inhibitory activity towards the XO enzyme with IC50-values of 6.2±0.6µg/ml and 8.9±0.8µg/ml, respectively. In comparison, IC50-values of allopurinol and oxypurinol were 2.6±0.9µg/ml and 1.0±0.2µg/ml, respectively. Thin-layer chromatographic analysis showed flavonoids to be present as the main constituents in the methanolic extracts. This is in line with literature data reporting F. ulmaria to contain 5.1–7.3% of flavonoids in the flowering tops . Since flavonoids have previously been described as inhibitors of XO , these constituents probably attribute to the activity of the methanolic extracts of F. ulmaria and F. vulgaris. The XO-inhibitory activity of F. ulmaria and F. vulgaris extracts further substantiates the traditional use of these medicinal plants in the treatment of gout.
References:  Madaus, G. (1938) Lehrbuch der biologischen Heilmittel. Georg Thieme Verlag, Leipzig.
 Gessner, O., Orzechowski, G. (1974) Gift- und Arzneipflanzen von Mitteleuropa. Carl Winter Universitätverlag, Heidelberg.
 Schlesinger, N. (2004) Drugs. 64:2399–2416.
 Lamaison, J.L. et al. (1992) Pharm. Acta Helv. 67:218–222.
 Cos, P. et al. (1998)J. Nat. Prod. 61:71–76.