Icariin

Icariin is a flavonol glycoside. Icariin inhibits PDE5 and PDE4 activities with IC₅₀ of 432 nM and 73.50 μM, respectively. Icariin also is a PPARα activator^[1]. It has exert anti-oxidative, anti-neuroinflammatory, and anti-apoptotic effects^[2].

In vitro experiment it shown that treatment of 10 or 20 μM induced 13.1 ± 2.1% and 18.2 ± 1.6% apoptosis in MDA‐MB‐453 cells respectively in comparison with control group. 4T1 cells were treated with 20 μM icariin triggered cell apoptosis^[3].

In vivo, rats were injected in 50 mg/kg Icariin significantly reduced paw swelling in carrageenan-injected animals and ameliorated carrageenan-induced paw histopathological alterations. Icariin obviously increased paw enzymatic and non-enzymatic antioxidants and decreased paw lipid peroxidation. Icariin decreased paw levels of inflammatory cytokines and NF-kB[4].

In vivo, rats were administrated with 25 mg/kg and 50 mg/kg icariin improved depression symptoms via regulation of the PI3K-AKT pathway, boosted the expression of the regulatory methylene p85 and catalytic methylene p110 of PI3K, increased the relative expression of p-AKT, and encouraged the expression of the anti-apoptosis factor Bcl-2, thus elevating the ratio of Bcl-2/Bax^[5]. In vivo, C57BL/6 J mice were administrated with 50 mg/kg/d icariin effectively attenuated alcohol consumption-induced atrial structural and electrical remodeling^[6].

References:

[1] Xin ZC, et al. Effects of icariin on cGMP-specific PDE5 and cAMP-specific PDE4 activities. Asian J Androl. 2003 Mar;5(1):15-8.

[2] Jin J, et al. An outline for the pharmacological effect of icariin in the nervous system. Eur J Pharmacol. 2019 Jan 5;842:20-32.

[3] Song L, et al. Icariin-induced inhibition of SIRT6/NF-κB triggers redox mediated apoptosis and enhances anti-tumor immunity in triple-negative breast cancer. Cancer Sci. 2020 Nov;111(11):4242-4256.

[4] El-Shitany NA, Eid BG. Icariin modulates carrageenan-induced acute inflammation through HO-1/Nrf2 and NF-kB signaling pathways. Biomed Pharmacother. 2019 Dec;120:109567.

[5] Cao LH, et al. PI3K-AKT Signaling Activation and Icariin: The Potential Effects on the Perimenopausal Depression-Like Rat Model. Molecules. 2019 Oct 15;24(20):3700.

[6] Yu LM, et al. Icariin attenuates excessive alcohol consumption-induced susceptibility to atrial fibrillation through SIRT3 signaling. Biochim Biophys Acta Mol Basis Dis. 2022 Oct 1;1868(10):166483.