Differentiation of skeletal osteogenic progenitor cells to osteoblasts with 3,4-diarylbenzopyran based amide derivatives: Novel osteogenic agents

Abstract

A series of 3,4-diarylbenzopyran based amide derivatives was synthesized and evaluated for osteogenic activity in in vitro and in vivo models of osteoporosis. Compounds 17a, 21b–c and 22a–b showed significant osteogenic activity in osteoblast differentiation assay. Among the synthesized compounds, 22b was identified as lead molecule which showed significant osteogenic activity at 1 pM concentration in osteoblast differentiation assay and at 1 mg kg−1 body weight dose in estrogen deficient balb/c mice model. In vitro bone mineralization and expression of osteogenic marker genes viz BMP-2, RUNX-2, OCN, and collagen type 1 further confirmed the osteogenic potential of 22b. Gene expression study for estrogen receptor α and β (ER-α and ER-β) in mouse calvarial osteoblasts (MCOs) unveiled that possibly 22b exerted osteogenic efficacy via activation of Estrogen receptor-β preferentially. In vivo pharmacokinetic, estrogenicity and acute toxicity studies of 22b showed that it had good bioavailability and was devoid of uterine estrogenicity at 1 mg kg−1 and inherent toxicity up to 1000 mg kg−1 body weight dose respectively.