Effects of coumestrol administration to pregnant and lactating mice on intestinal alkaline phosphatase activity

Abstract

The present study was conducted to clarify the effects of coumestrol administration on Ca metabolism during pregnancy and in lactating mice. From 6.5 to 16.5 days post coitus (dpc), pregnant mice were administered coumestrol at 200 µg/kg body weight/day. The duodenum, jejunum and blood samples were obtained at 17.5 dpc or 10 days after parturition (dap). Coumestrol administration decreased alkaline phosphatase (ALP) activity and mRNA expression of IAP and estrogen responsive genes, c-fos and vascular endothelial growth factor (VEGF), in the duodenum and jejunum of pre-delivery mice. In lactating mice, the ALP activity and mRNA expression of IAP were not changed, although coumestrol administration decreased mRNA expression of c-fos in the duodeum and VEGF in the jejunum. Coumestrol did not affect serum Ca and the expression of vitamin D receptor protein in the duodenum and jejunum. Thus, coumestrol administration during pregnancy may decrease the mRNA expression of IAP and the ALP activity in the intestine of the pre-delivery mice through ERα, but coumestrol had little effect on intestinal ALP activity at 10 days after parturition.

Effects of bisphenol A administration to pregnant mice on serum Ca and intestinal Ca absorption

“…2003). In previous studies (Kirihata et al . 2008, 2011), coumestrol administration at 200 µg/kg body weight/day during pregnancy caused a decrease in IALP activity and mRNA expression of IALP, c‐fos and VEGF in the duodenum of pregnant mice, although serum Ca was not affected.…”

“…2006). However, our previous studies (Kirihata et al . 2008, 2011) showed that coumestrol administration at 200 µg/kg body weight/day during pregnancy decreased messenger RNA (mRNA) expression of IALP and estrogen responsive genes, c‐fos and vascular endothelial growth factor (VEGF), and the activity of IALP in the duodenum and jejunum of mice at 16.5 days post coitus (dpc) and 1 day after birth.…”

“…2008, 2011) showed that coumestrol administration at 200 µg/kg body weight/day during pregnancy decreased messenger RNA (mRNA) expression of IALP and estrogen responsive genes, c‐fos and vascular endothelial growth factor (VEGF), and the activity of IALP in the duodenum and jejunum of mice at 16.5 days post coitus (dpc) and 1 day after birth. Thus, in the presence of high levels of endogenous estrogen in mice before parturition, coumestrol administration may interrupt the ER‐derived increase of ALP activity (Kirihata et al . 2011).…”

Intestinal alkaline phosphatase: novel functions and protective effects

“…AAA) flour both were found to decrease colonic AP activity in a rat model of colitis . Coumestrol, a phytoestrogen known to regulate intestinal calcium absorption, was found to inhibit IAP gene expression and enzyme activity, although differential regulation was evident in the duodenum and the jejunum in neonatal pups and lasted until 10 days postparturition . It was suggested that estrogen receptor‐alpha (ER‐α) may be involved in this transient inhibition.…”

Effects of coumestrol administration to maternal mice during pregnancy and lactation on renal Ca metabolism in neonatal mice

“…This corresponds to about 458–570 µg/kg body weight/day on the average body weight of Japanese adults. Based on less than half this limit for isoflavone intake, we previously examined the effects of coumestrol on Ca metabolism in pregnant mice given 200 µg/kg body weight/day and showed that coumestrol administration decreased the messenger RNA (mRNA) expression of IALP and the activity of IALP in the duodenum of mice at 16.5 days post coitus (dpc) and 1 day after birth (dap) (Kirihata et al . 2008, 2011).…”