WHO monographs on selected medicinal plants - travolekar.ru

Radix Panacis Quinquefolii
CYP1 activities. However, at a higher concentration of ginsenoside (50 μg/
ml), Rb1, Rb2, Rc, Rd and Rf inhibited these activities. Thus, extracts of
the root, which were not treated with calf serum or subjected to acid hydrolysis,
inhibited CYP1 catalytic activity, but the effects were not due to
Rb1, Rb2, Rc, Rd, Re, Rf or Rg1 (45).
Ginsenoside C was more toxic than ginsenoside A2 after intraperitoneal
administration to mice. Toxicity was not observed after oral administration
of any of the ginsenosides. The genins, panaxadiol and panaxatriol,
were more toxic and had larger volumes of distribution than the
ginsenosides (46).
Clinical pharmacology
Various extracts of the roots, with a specific ginsenoside profile, are reported
to decrease postprandial glycaemia. An extract of the roots (containing
1.66% total ginsenosides, 0.9% (20S)-protopanaxadiol ginsenosides
and 0.75% (20S)-protopanaxatriol) was assessed on the glycaemic
index following a 75 g oral glucose tolerance test in a randomized, singleblind
study involving 12 normal volunteers. Each subject received 6 g of
the extract orally, or a placebo, 40 minutes before a 75 g oral glucose tolerance
test. Venous blood samples were drawn at -40, 0, 15, 30, 45, 60, 90
and 120 min. Repeated measures analysis of variance demonstrated that
there was no significant effect of the extract on incremental plasma glucose
or insulin or their areas under the curve; indices of insulin sensitivity
and release (PI30-0/PG30-0) calculated from the oral glucose tolerance
test were also unaffected (18).
The effect of escalation of the dose and dosage interval of a root product
(500 mg powdered root per capsule) was assessed in individuals who
did not have diabetes to determine whether further improvements in glucose
tolerance (seen previously when 3 g of crude drug was taken 40 minutes
before a 25.0 g glucose challenge) could be attained. Ten healthy volunteers
were randomly assigned to receive 0 (placebo), 3, 6 or 9 g of crude
drug prepared from the ground root at 40, 80 or 120 minutes before a
25.0 g oral glucose challenge. Capillary blood glucose was measured prior
to ingestion of the crude drug or placebo capsules and at 0, 15, 30, 45, 60
and 90 minutes from the start of the challenge. As compared with the
placebo, 3, 6 and 9 g of crude drug reduced postprandial incremental glucose
at 30, 45 and 60 minutes from the start of the challenge (p < 0.05); 3 g
and 9 g of the crude drug also did so at 90 minutes. All doses of the crude
drug reduced the area under the incremental glucose curve (3 g, 26.6%;
6 g, 29.3%; 9 g, 38.5%) (p < 0.05). The crude drug taken at different times
did not have any additional influence on postprandial glycaemia (19). In a
subsequent investigation, 10 patients with type 2 diabetes were randomly
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