Hypoglycemic property of soy isoflavones from hypocotyl in Goto-Kakizaki diabetic rats

Abstract

The present study was carried out to investigate the hypoglycemic effect of soy isoflavones from hypocotyl in GK diabetic rats. A single administration and long-term administration tests were conducted in GK diabetic rats to test the hypoglycemic effect of soy isoflavones. At the end of long-term administration trial, blood protein, cholesterol, triglyceride, glycosylated serum protein, C-reactive protein, insulin, aminotransferase, lipid peroxide, interleukin-6, tumor necrosis factor-α were estimated. Inhibition of soy isoflavones against α-amylase and α-glucosidase, as well as on glucose uptake into brush border membrane vesicles or Caco-2 cells were determined in vitro. In single administration experiment, soy isoflavones reduced postprandial blood glucose levels in GK rats. In long-term administration, hypoglycemic effect of soy isoflavones was first observed at week 12 and maintained till week 16. A significant reduction in fasting blood glucose, C-reactive protein, and lipid peroxide was noted at week 16. However, there was no significant treatment effect on blood insulin. Furthermore, soy isoflavone administration resulted in significant decreases in glycosylated serum protein, tumor necrosis factor-α, and interleukin-6. Other biochemical parameters, such as protein, cholesterol, triglyceride and aminotransferases were not modified, however. The results in vitro showed that soy isoflavones showed a potent inhibitory effect on intestinal α-glucosidase, but not on pancreatic α-amylase. Soy isoflavones also decreased glucose transport potency into brush border membrane vesicles or Caco-2 cells. It is concluded that soy isoflavones from hypocotyl, performs hypoglycemic function in GK rats with type 2 diabetes, maybe via suppression of carbohydrate digestion and glucose uptake in small intestine.

Soy Isoflavones Ameliorate Metabolic and Immunological Alterations of Ovariectomy in Female Wistar Rats: Antioxidant and Estrogen Sparing Potential

“…Furthermore, it is logic to find the downregulation of CRP level together with reduced TNF- α and IL-2 where CRP is produced by hepatic cells in response to such cytokines [97]. The decrement in CRP after soy isoflavone treatment was in harmony with results of Fanti et al [98] and Jin et al [99].…”

The effects of isoflavone supplementation plus combined exercise on salivary markers of oxidative stress in postmenopausal women

“…(45,46) Some authors showed that chronic soy ISO even from hypocotyl can decrease lipid perioxidation and some pro inflammatory cytokines markers. (29) The efficiency of TBARS inhibition may depend on the individual isoflavones concentration in the extract, with some compounds having low or moderate efficiency to inhibit TBARS, (46) which may explain the slight interaction observed in this study (p = 0.037), and also why other studies found no changes in lipid peroxidation markers with ISO. (32,33) One of the main benefits from exercise training is related to improvements in antioxidant defense.…”

“…In some studies, there was a decrease in ROS production, and an increase in SOD in postmenopausal women, (26,27) other showed that genistein, a soy isoflavone, or the soy isoflavone from hypocotyl could decrease oxidative stress via lowering lipid peroxidation, and improving antioxidant enzymes. (28,29) Besides, other studies find that a high isoflavone consumption, as well as exercise, is effective in increasing nitrite concentrations and improving endothelial function. (30,31) However, there are also studies that did not report any effect in oxidative markers with ISO.…”

Induction of a 5-lipoxygenase product by daidzein is involved in the regulation of influenza virus replication

“…(9)(10)(11)(12)(13) Soy isoflavones, such as daidzein, glycitein, and genistein, (14) are a group of compounds present in soybean and function as potent antioxidants. (15,16) Jin et al (17) reported the effect of soy isoflavones, including daidzein (61.7%), glycitein (21.5%) and genistein (16.2%), on diabetic rats. They showed that an improvement in postprandial blood glucose levels and a significant suppression of blood lipid peroxide can be achieved by single or long-term administration of soy isoflavones, respectively.…”

“…They showed that an improvement in postprandial blood glucose levels and a significant suppression of blood lipid peroxide can be achieved by single or long-term administration of soy isoflavones, respectively. (17) Additionally, soy isoflavones act as phytoestrogens and interact with animal and human estrogen receptors and produce non-hormonal effects. (18)(19)(20)(21)(22)(23)(24) We found that daidzein and glycitein inhibited influenza virus replication and suggested that the regulation by daidzein is not directly associated with viral enzymes but rather with host-cellular metabolism (unpublished data).…”