Modulation of Gene Expression by Polyalthia longifolia in Postmenopausal Women with Coronary Artery Disease: An In Vitro Study

Abstract

Chronic underlying inflammation is involved in the pathophysiology of coronary artery disease (CAD). Polyalthia longifolia var. pendula bark extract (PLE) is known to exhibit anti-inflammatory activity and has high content of phytosteroids. Since phytosteroids mimic estrogen structurally, we postulated that PLE may provide protection in postmenopausal women against CAD. Thus the effect of PLE has been explored on expression of estrogen receptors (ERalpha and ERbeta) and inflammatory inducible nitric oxide synthase (iNOS) genes in vitro in peripheral blood mononuclear cells (PBMCs) obtained from postmenopausal women. A total of 20 postmenopausal women were included in the present study. Group I (N = 10) included women with angiographically proven CAD, and group II (N = 10) is composed of equal number of age-matched healthy postmenopausal females as controls. Significantly low levels of serum 17-beta estradiol were observed in subjects of group I as compared to group II (p < 0.01). A marked increase in L: -citrulline levels (p > 0.05) and significantly augmented levels of reactive nitrogen intermediates (p < 0.05) were observed in group I subjects. PLE significantly attenuated PMA-induced expression of both ERalpha and ERbeta receptors and inflammatory iNOS gene in vitro in a dose- and time-dependent manner and had an additive effect on these genes when compared with tamoxifen. Ours is the first report to demonstrate that PLE contains certain bioactive principles, which possess anti-inflammatory and estrogenic properties, and thereby hold the promise to be screened for their anti-atherogenic potential in experimental animals to favorably alter several other markers of cardiovascular risk.

Polyalthia longifolia Promises to be a Potential Nutraceutical

“…In addition, a defatted extract of P. longifolia root bark was showed a significant ability to reduce blood pressure [16]. Mittal et al have demonstrated a significant decrease in the mRNA expression of iNOS in PMA-stimulated blood mononuclear cells (isolated from postmenopausal women with CAD) in presence of ethanolic extract of P. longifolia and therefore suggested to have anti-inflammatory and cardio-protective effects [17]. Bark extract of P. longifolia has high content of phytosteroids, which may mimic estrogen structurally and therefore may modulate the estrogen receptor expression.…”

“…Bark extract of P. longifolia has high content of phytosteroids, which may mimic estrogen structurally and therefore may modulate the estrogen receptor expression. Though, there is no specific evidence but bark extract may act as SERM (selective estrogen receptor modulators) to effect on the downstream signaling cascades driven through estrogen receptor was demonstrated in the study by Mittal et al [17]. A clerodane diterpenoid from Formosan P. longifolia var pendula has been shown to significantly inhibit the generation of superoxide anion and the release of elastase in activated human neutrophils in a concentration dependent manner.…”