The in vivo dynamic distribution of Ginkgo extract (pharmacokinetics) was investigated by several methods including positron emission tomography (PET) and LC-MS/MS [3, 4]. In general, the extent of bioavailability of ginkgolids is high, and food intake does not change it . Intravenous administration of Ginkgo extract leads to its biphasic elimination with a prominent initial phase (half-life of 0.3 h, with peak at 10min), followed by a slower terminal phase (half-life of 1.5h). Tissue concentration declines by several-fold during the first 6 h and the metabolites are mainly excreted in the urine (40 to 50%) and feces (less than 30%) and traces by bile.
Interestingly, as shown by PET imaging in vivo, at least the ginkgolid B exists in two forms in the body: the original with its lactone rings closed and a second form with one of the rings open. The original form is taken up rapidly by various organs including the liver, the intestine and possibly the stomach, and consequently in plasma, the proportion of open form increases dramatically with time to shift slowly towards equilibrium. Polyphenols are usually non-lipophilic compounds and cannot cross easily through the plasma membrane. As suggested by Ramasamy , they might interact with plasma membrane transporters or receptors triggering intracellular signaling pathways. It is interesting that the first receptor for a dietary polyphenol has been identified for EGCG, the 67 kDa laminin receptor on vascular cells . The presence of polyphenol receptors or transporters in the brain remains to be established. The beneficial effects of polyphenols appear to be a promising class of compounds for neuroprotection.
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Many women who have recently given birth are always interested in attempting to lose some of that extra weight that traditionally accompanies having a baby. What many of these women do not entirely realize is the fact that breast-feeding can not only help provide the baby with essential vitamins and nutrients, but can also help in the weight-loss process.