Silydianin is an active constituent of Silybium marianum, with exhibit anti-collagenase, antitumor and anti-elastase activities. Silydianin is a natural protein tyrosine phosphatase 1B (PTP1B) with an IC50 of 17.38 μM. Silydianin has inhibitory effect on the in vitro production and release of oxidative products[1][2][3].
References:
[1]. Vostálová J, et al. Skin Protective Activity of Silymarin and its Flavonolignans. Molecules. 2019 Mar 14;24(6).
[2]. Qin N, et al. Identification of flavonolignans from Silybum marianum seeds as allosteric protein tyrosine phosphatase 1B inhibitors. J Enzyme Inhib Med Chem. 2018 Dec;33(1):1283-1291.
[3]. Zielińska-Przyjemska M, et al. An in vitro study of the protective effect of the flavonoid silydianin against reactive oxygen species. Phytother Res. 2006 Feb;20(2):115-9.