There is no ‘ Conundrum ’ of InsP 6 Robin
نویسندگان
چکیده
Indirect assays have claimed to quantify phytate (InsP6) levels in human biofluids, but these have been based on the initial assumption that InsP6 is there, an assumption that our more direct assays disprove. We have shown that InsP6 does not and cannot (because of the presence of an active InsP6 phosphatase in serum) exist in mammalian serum or urine. Therefore, any physiological effects of dietary InsP6 can only be due either to its actions in the gut as a polyvalent cation chelator, or to inositol generated by its dephosphorylation by gut microflora.
منابع مشابه
Synthesis of diphosphoinositol pentakisphosphate by a newly identified family of higher inositol polyphosphate kinases
Inositol (1,4,5) trisphosphate (Ins(1,4,5)P(3)) is a well-known messenger molecule that releases calcium from intracellular stores. Homologues with up to six phosphates have been characterized and recently, homologues with seven or eight phosphate groups, including pyrophosphates, have been identified. These homologues are diphosphoinositol pentakisphosphate (PP-InsP(5)/InsP(7)) and bis(diphosp...
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Background: Within-breath reactance from forced oscillometry estimates resistance via its inspiratory component (Xrs,insp) and flow limitation via its expiratory component (Xrs,exp). Aim: To assess whether reactance can detect recovery from an exacerbation of chronic obstructive pulmonary disease (COPD). Method: 39 subjects with a COPD exacerbation were assessed on three occasions over 6 weeks ...
متن کاملMeasurement of physiological recovery from exacerbation of chronic obstructive pulmonary disease using within-breath forced oscillometry.
BACKGROUND Within-breath reactance from forced oscillometry estimates resistance via its inspiratory component (X(rs,insp)) and flow limitation via its expiratory component (X(rs,exp)). AIM To assess whether reactance can detect recovery from an exacerbation of chronic obstructive pulmonary disease (COPD). METHOD 39 subjects with a COPD exacerbation were assessed on three occasions over 6 w...
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