Effect of fructo-oligosaccharide supplementation in soya beverage on the intestinal absorption of calcium and iron in newly weaned rats

Studies have shown the positive effects of prebiotics on the intestinal absorption of Ca and Fe. The present study evaluated the effect of fructo-oligosaccharide (FOS) supplementation in soya beverage (SB) on absorption mechanisms of Ca and Fe in recently weaned rats. Male Wistar rats were divided into four groups: lactose-free cows' milk (CM), lactose-free CM with FOS (0·8 g/100 ml) (CMF), SB and soya beverage with FOS (0·8 g/100 ml) (SBF). These rats were euthanised after 1 week of treatment. Organ weight, pH of the caecal content and absorption mechanisms of Ca and Fe were evaluated. The results showed that the weight of the caecal contents increased in the CMF and SBF groups, and the pH of the caecal contents was lower in these groups. The Hb levels of the CMF and SB groups were higher when compared with that of the CM group and lower in relation to the SBF group. The apparent Ca and Fe absorption and apparent Ca retention in the CM group were higher when compared with the SB group, whereas in the CMF group, they were higher in relation to the SBF group. Divalent metal transporter 1 (DMT1) protein expression in the duodenum was higher in the SBF group than in the SB and CMF groups. SB resulted in lower intestinal Ca absorption and higher Hb concentration, despite the lower apparent Fe absorption in relation to CM. Supplementation with FOS provided beneficial effects on Hb and DMT1 protein expression in the duodenum, in addition to improving the absorption process.

Meta-analysis across Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium provides evidence for an association of serum vitamin D with pulmonary function

The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)-pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D-pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (P race difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (P race difference=0·56). Among EA, the 25(OH)D-FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.