The lactating and NPNL women were a subset of women who were participating in a larger, longitudinal study designed to investigate the influence of lactation on bone. Details of these women have been reported previously [2] and [4]. This paper includes data from 48 women who lactated for more than 3 months and 23 NPNL women studied concurrently. It also includes one extra NPNL and one lactating woman whose data were not available at the time the previous papers were completed. IDH tumor The inclusion of NPNL women in the study enabled consideration of the potential skeletal changes in women due to advancing age and also

investigated

SB203580 molecular weight possible shifts in DXA performance over the study period. Approval for the study was obtained from the Ethical Committee of the MRC Dunn Nutrition Unit (of which MRC Human Nutrition Research was formerly a part) and written informed consent was obtained from each participant. Lactating mothers visited the Dunn Clinical Nutrition Centre, Cambridge, UK at approximately 2 weeks postpartum, and for repeat measurements at 3, 6 and 12 months postpartum. An additional visit was made 3 months after breast feeding had stopped for women who lactated for more than 9 months. Peak-lactation was defined as 3 months postpartum for the 13 mothers who breast-fed for 3–6 months and 6 months postpartum for the 35 mothers who breast-fed for more than 6 months. Post-lactation was defined as 1-year postpartum for the 25 women who lactated for less than 9 months and 3 months post-lactation for the 21 women who lactated for more than 9 months. Two

women were unable to be measured post-lactation because they had become pregnant again. All but one of the women was amenorrheic at the Amoxicillin time of their peak-lactation visit and all women had resumed menstruation at the time of their post-lactation visit. Measurements were performed on the following days postpartum, expressed as mean (standard deviation [SD], range): 2 weeks postpartum 17 (5, 10–42) days, peak-lactation 159 (42, 85–226) days, post-lactation 426 (131, 269–932) days. Results reported for lactating women are changes from 2 weeks postpartum to peak-lactation and from 2 weeks postpartum to post-lactation. Results reported for NPNL women are changes from baseline to 319 (67, 152–406) days after baseline. Bone mineral measurements on the left hip were performed using DXA (QDR-1000W; Hologic Inc, Bedford, MA). Hip scans were analysed using the hip structural analysis (HSA) program (version 1) [26].

As expected, when KO POBs were co-cultured with KO BMMs, medium PGE2 was undetectable in vehicle or PTH-stimulated cultures [31] and [33]. WT BMMs (plated

at 10:1 ratio with POBs) made more PGE2 under basal conditions than WT POBs. The basal level of PGE2 production by POBs was likely due to the serum induction of COX-2 [34]. PTH stimulated PGE2 production 2- to 3-fold in co-cultures with WT POBs but had little effect in cultures with KO POBs, consistent with the expected absence of PTH receptors on BMMs. The small increase in PGE2 in the WT BMM, KO POB co-culture might be due to PTH-stimulated RANKL expression in the POBs, which subsequently Selleckchem Omipalisib induced COX-2 in BMMs [40]. In vehicle-treated cultures, the Osteocalcin levels decreased as PGE2 levels decreased ( Table 1). PTH-stimulated Osteocalcin mRNA expression was increased 20-fold relative to vehicle treatment in KO BMM-KO POB cultures, which had no detectable PGE2 production. In all other combinations, which contained WT POBs or WT BMMs and did produce measurable

PGE2, PTH-stimulated Osteocalcin expression was inhibited relative to the KO-KO combination. Hence, either POBs or BMMs expressing COX-2 were sufficient to prevent the PTH-stimulated www.selleckchem.com/products/pd-166866.html OB differentiation in this culture system. In many of our experiments in BMSC cultures (Fig. 1 and Fig. 3)

or in cultures with both POBs and BMMs (Table 1), but not in POBs cultured alone (Fig. 5), PTH given in the presence of COX-2 expression resulted in decreased Alp or Osteocalcin expression relative to vehicle-treated cultures. Since some of the OB differentiation in vehicle-treated cultures is explainable by the serum induction of COX-2 expression and endogenous PGE2 production ( Table 1) [34], this observation suggests that, in the presence of BMMs, the stimulatory effect of endogenous PGE2 on OB differentiation was suppressed in the presence of PTH. To look at 4��8C this possibility more directly, we treated BMSC cultures with PTH (10 nM), PGE2 (10 nM) and the combination (Fig. 6A). PGE2 stimulated Bone sialoprotein (Bsp) mRNA at 14 days in both WT and Cox-2 KO BMSCs. (The small but significant increase in the effects of PGE2 in KO cells has been seen before and may be due to down regulation of PGE2 receptors due to chronic exposure to endogenous PGE2 in WT cultures). Although both PTH and PGE2 individually stimulated Bsp mRNA expression in KO cultures, the combination of PTH and PGE2 had no stimulatory effect. To better understand the dose range over which these effects occurred, we treated Cox-2 KO BMSCs with PTH (10 nM) ± PGE2 (0.1 nM to 0.1 μM) for 14 days ( Fig. 6B).