Soy isoflavones affect platelet thromboxane A2 receptor density but not plasma lipids in menopausal women

Effects of soy isoflavone extract supplements on blood pressure in adult humans: systematic review and meta-analysis of randomized placebo-controlled trials

“…1) resulted in 3740 potentially relevant articles. Fourteen randomized placebo-controlled trials [14][15][16][17][18][19][20][21][22][23][24][25][26][27] met all the inclusion criteria and were included in the systematic review (Fig. 2).…”

“…Two trials [16,27] included men and women, the remaining 12 trials included only perimenopausal, postmenopausal women, or both. Four trials [15,22,25,27] did not clearly describe the form of isoflavones used; we assumed them to be aglycone equivalents for calculating average dosage of isoflavones for all included trials. If the studies did not report detailed composition of soy isoflavones used, we calculated the aglycone equivalent value by multiplying the total isoflavones by 0.61 [28].…”

Soy Isoflavones as Bioactive Ingredients of Functional Foods

“…Genistein inhibits TxA 2 -mediated platelet responses (Nakashima et al, 1991), acting as an antagonist of TxA 2 receptors, and the same action has been described for equol (Munoz et al, 2009). These molecules compete with TxA 2 receptors and decrease their density (Garrido et al, 2006). Genistein and daidzein inhibit platelet adhesion and aggregation (Sargeant et al, 1993;Gottstein et al, 2003;Borgwardt et al, 2008) and inhibit the secretory activity of platelets (Guerrero et al, 2005;Munoz et al, 2009).…”

Soy and Soy-Based Foods: Role in Health and Nutrition

“…On the other hand, individual isoflavones appear to play an important role in other biochemical processes related to CVD, for instance, genistein and daidzein seem to inhibit the nitric oxide (NO) and tumour necrosis factor alpha (TNF-alpha) production, showing genistein a greater inhibitory effect (Gottstein et al 2003). Regarding to hemostasis, there is still uncertainty about their role in the hemostatic equilibrium; to date, these phytochemicals are involved in platelet aggregation mechanisms, including the blockage of the calcium channels (Dobrydneva et al 2002) or the thromboxane A2 receptor (Muñoz et al 2009), the reduction in the density of thromboxane A2 receptors (Garrido et al 2006), or the interference with different platelet singnalling pathways triggered by thrombin (Navarro-Nuñez et al 2009). On the other hand, phytates have been also evaluated in terms of protecting against CVD risks in postmenopausal women.…”