American
ginseng (Panax quinquefolius L.) is one
of the most commonly used herbal medicines in the West. It has been
reported to possess significant antitumor effects that inhibit the
process of carcinogenesis. However, the mechanisms underlying its
anticancer effects remain largely unresolved. In this study, we investigated
the cancer chemopreventive effects of American ginseng on the progression
of high fat (HF) diet-enhanced colorectal carcinogenesis with a genetically
engineered ApcMin/+ mouse
model. The metabolic alterations in sera of experimental mice perturbed
by HF diet intervention as well as the American ginseng treatment
were measured by gas chromatography time-of-flight mass spectrometry
(GC-TOFMS) and liquid chromatography time-of-flight mass spectrometry
(LC-TOFMS) analysis. American ginseng treatment significantly extended
the life span of the ApcMin/+ mouse. Significant alterations of metabolites involving amino
acids, organic acids, fatty acids, and carbohydrates were observed
in ApcMin/+ mouse in
sera, which were attenuated by American ginseng treatment and concurrent
with the histopathological improvement with significantly reduced
tumor initiation, progression and gut inflammation. These metabolic
changes suggest that the preventive effect of American ginseng is
associated with attenuation of impaired amino acid, carbohydrates,
and lipid metabolism. It also appears that American ginseng induced
significant metabolic alterations independent of the ApcMin/+ induced metabolic changes. The
significantly altered metabolites induced by American ginseng intervention
include arachidonic acid, linolelaidic acid, glutamate, docosahexaenoate,
tryptophan, and fructose, all of which are associated with inflammation
and oxidation. This suggests that American ginseng exerts the chemopreventive
effects by anti-inflammatory and antioxidant mechanisms.