Urinary isoflavones are increased in adults, but decreased in children, consuming soy when on oral antibiotic therapy.
The goal of this study was to evaluate how oral antibiotics (OABX) change the appearance of isoflavones (IFLs) in adults and children after soy consumption. The urinary IFL excretion rate (UIER) known to reflect circulating IFLs was hypothesized to change due to intestinal microflora changes by OABX. Subjects provided urine collections in pairs of a baseline urine and an overnight urine before and after consuming soy nuts first during OABX treatment and then again when healthy. During OABX versus when healthy, UIER (nmol/h/kg) in adults (n = 12) was increased (P < 0.05) for daidzein (35.2 +/- 7.2 vs. 18.9 +/- 2.4), daidzein + genistein + glycitein [nonmetabolites (NM); 42.6 +/- 8.0 vs. 23.6 +/- 2.9), and total isoflavonoids (Total IFLs; daidzein + genistein + glycitein + dihydrodaidzein + dihydrogenistein + equol + O-desmethylangolensin) (51.5 +/- 10.3 versus 29.6 +/- 4.7). In contrast, children (n = 7) showed reduced UIER (P < 0.05) when on OABX versus when healthy for daidzein (36.3 +/- 6.4 vs. 46.8 +/- 4.7), dihydrodaidzein (1.2 +/- 0.6 vs. 3.0 +/-1.1), NM (46.3 +/- 8.2 vs. 59.5 +/- 6.0), dihydrodaidzein + dihydrogenistein + equol + O-desmethylangolensin (1.0 +/- 0.8 vs. 4.3 +/- 1.3), and Total IFLs (48.2 +/- 8.5 vs. 63.8 +/- 6.4).
Franke
Adrian A
AA
Cancer Research Center of Hawai'i, Natural Products & Cancer Biology Program, Honolulu, Hawaii 96813, USA. adrian@crch.hawaii.edu
Halm
Brunhild M
BM
Ashburn
Leslie A
LA
D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D015415:Biomarkers / Q000652:urine; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D019833:Genistein / Q000652:urine; D006801:Humans; D007529:Isoflavones / Q000652:urine*; D008297:Male; D048789:Phytoestrogens / Q000652:urine; D045730:Soy Foods; D013025:Glycine max
D000900:Anti-Bacterial Agents; D015415:Biomarkers; D007529:Isoflavones; D048789:Phytoestrogens; C004742:daidzein; C086566:glycitein; D019833:Genistein