modulate the vascular reactivity (Li et al. 2006) and could lower the bile acid
synthesis, hepatic lipid synthesis, and cholesterol reabsorption (Ricketts et al.
2005). However, recent studies like that of Engelbert et al. (2016) and Taku et al.
(2008), wherein no significant changes in the total cholesterol were reported in
postmenopausal women taking isoflavone supplements/extracts, have led to a wide
disagreement regarding the hypolipidemic role of soy isoflavones. Moreover, recent
research suggests that a synergistic interaction of soy isoflavones and soy protein
augments the blood lipid profile and, hence, exerts hypolipidemic effect (Xiao et al.
2014; Kobayashi et al. 2014).
1.4.3 In Hypertension
Soybean and its bioactive components (soy protein, isoflavones, etc.) have been
reported to mitigate hypertension by mechanisms involving vasodilation and
inhibition of key enzyme involved in the blood pressure regulation (Jackson
et al. 2011). In the postmenopausal pre-diabetic hypertensive women, soy protein
and isoflavone intake attenuated the blood pressure (Welty et al. 2007; Liu et al.
2013). Colacurci et al. (2005) studied the effect of isoflavone supplementation in
postmenopausal women for 6 months and reported improvement in endothelial
vasodilation along with reduction in cellular adhesion molecules. However, other
studies have found that soy isoflavone supplementation can exert hypotensive
effect in hypertensive but not in normotensive adults (Taku et al. 2010; Patten
et al. 2016). Since soybean is a rich source of arginine which in turn is a precursor
to nitric oxide in the L-arginine pathway, thus, it improves endothelial function and
demonstrates hypotensive effect (Bai et al. 2009; Dong et al. 2011). Also, in vitro
studies have showed that soy pulp containing oligopeptides and fiber in high
amounts exhibited anti-angiotensin-converting enzyme activity and, hence, hypotensive effect (Nishibori et al. 2017).
1.4.4 In Obesity
Overweight and obesity have a profound impact on global health, and it is a risk
factor for several chronic diseases like diabetes and hypertension. Epidemiological
evidence suggests a positive association between soy consumption and weight
management by enhancing insulin resistance and subsiding lipoprotein lipase activity (Velasquez and Bhathena 2007; Ørgaard and Jensen 2008; Muscogiuri et al.
2016).
Kurrat et al. (2015) reported that lifelong intake of soy isoflavones reduced the
body weight, serum leptin, and visceral fat mass and resulted in smaller adipocytes in
female Wistar rats. In another study, diet-induced obese male rats when fed with soy
isoflavones showed enhanced lipolysis and β-oxidation along with suppressed
1 Soybean (Glycine max)
1 9
synthesis, hepatic lipid synthesis, and cholesterol reabsorption (Ricketts et al.
2005). However, recent studies like that of Engelbert et al. (2016) and Taku et al.
(2008), wherein no significant changes in the total cholesterol were reported in
postmenopausal women taking isoflavone supplements/extracts, have led to a wide
disagreement regarding the hypolipidemic role of soy isoflavones. Moreover, recent
research suggests that a synergistic interaction of soy isoflavones and soy protein
augments the blood lipid profile and, hence, exerts hypolipidemic effect (Xiao et al.
2014; Kobayashi et al. 2014).
1.4.3 In Hypertension
Soybean and its bioactive components (soy protein, isoflavones, etc.) have been
reported to mitigate hypertension by mechanisms involving vasodilation and
inhibition of key enzyme involved in the blood pressure regulation (Jackson
et al. 2011). In the postmenopausal pre-diabetic hypertensive women, soy protein
and isoflavone intake attenuated the blood pressure (Welty et al. 2007; Liu et al.
2013). Colacurci et al. (2005) studied the effect of isoflavone supplementation in
postmenopausal women for 6 months and reported improvement in endothelial
vasodilation along with reduction in cellular adhesion molecules. However, other
studies have found that soy isoflavone supplementation can exert hypotensive
effect in hypertensive but not in normotensive adults (Taku et al. 2010; Patten
et al. 2016). Since soybean is a rich source of arginine which in turn is a precursor
to nitric oxide in the L-arginine pathway, thus, it improves endothelial function and
demonstrates hypotensive effect (Bai et al. 2009; Dong et al. 2011). Also, in vitro
studies have showed that soy pulp containing oligopeptides and fiber in high
amounts exhibited anti-angiotensin-converting enzyme activity and, hence, hypotensive effect (Nishibori et al. 2017).
1.4.4 In Obesity
Overweight and obesity have a profound impact on global health, and it is a risk
factor for several chronic diseases like diabetes and hypertension. Epidemiological
evidence suggests a positive association between soy consumption and weight
management by enhancing insulin resistance and subsiding lipoprotein lipase activity (Velasquez and Bhathena 2007; Ørgaard and Jensen 2008; Muscogiuri et al.
2016).
Kurrat et al. (2015) reported that lifelong intake of soy isoflavones reduced the
body weight, serum leptin, and visceral fat mass and resulted in smaller adipocytes in
female Wistar rats. In another study, diet-induced obese male rats when fed with soy
isoflavones showed enhanced lipolysis and β-oxidation along with suppressed
1 Soybean (Glycine max)
1 9