Silychristin is an abundant flavonolignan present in the fruits of Silybum marianum, with antioxidant properties. Silychristin is a potent inhibitor of the thyroid hormone transporter MCT8, and elicits a strong inhibition of T3 uptake with an IC50 of 110 nM[1][2].
Silychristin exhibits a strong inhibition of MCT8-mediated T3 uptake with an IC50 of 110 nM in MCT8 overexpressing MDCK1-cells[2].Silychristin causes no cytotoxic for fibroblasts[3].Silychristin (6.5-75 μM; 24 hours) diminishes UVA toxicity and reduces ROS generation, and the protective effect is dose-dependent[3].Silychristin (12.5μM, 25μM) reduces the metalloproteinase-1 (MMP-1) level in cells[3].
References:
[1]. Biedermann D, et al. Silychristin: Skeletal Alterations and Biological Activities. J Nat Prod. 2016 Dec 23;79(12):3086-3092.
[2]. Johannes J, et al. Silychristin, a Flavonolignan Derived From the Milk Thistle, Is a Potent Inhibitor of the Thyroid Hormone Transporter MCT8. Endocrinology. 2016 Apr;157(4):1694-701.
[3]. Rajnochová Svobodová A, et al. A pilot study of the UVA-photoprotective potential of dehydrosilybin, isosilybin, silychristin, and silydianin on human dermal fibroblasts. Arch Dermatol Res. 2019 Aug;311(6):477-490.