Ostruthin (Ostruthine) is a natural coumarin with antimicrobial activity that can effectively inhibit the growth of a wide range of mycobacteria with a minimum inhibitory concentration of MIC= 3.4-107.4 μM.

Serum-induced proliferation (rat aortic VSMCs, resazurin assay):11 μM, DNA synthesis (rat aortic VSMCs, BrdU assay):17 μM

Ostruthin exhibits potent antiproliferative activity against vascular smooth muscle cells (VSMCs) in vitro. In rat aortic VSMCs, ostruthin inhibited 10% serum-induced proliferation with an IC₅₀ of 11 ± 2 μM (resazurin assay) and suppressed DNA synthesis with an IC₅₀ of 17 ± 6 μM (BrdU assay). No significant cytotoxicity was observed at active concentrations (≤30 μM, cell viability >92%)[1].

Ostruthin, administered intraperitoneally at 5 mg/kg in ovariectomized female rats, significantly increased core body temperature within 30 minutes, with effects lasting over 3 hours. This thermogenic effect was observed regardless of progesterone treatment and is likely mediated by activation of TREK1/2 potassium channels, suggesting Ostruthin's potential for alleviating low body temperature symptoms in postmenopausal women[2].