Chemistry Reference
In-Depth Information
The choice of fibers for medical use has probably not considered the content of
vitamins and antioxidants as it should. Pectin has demonstrated high antioxidant
ability, but most of the fibers generally used are not particularly rich in antioxi-
dants. Numerous other plant fibers exist that should be considered as medical fibers
and used either as replacement for or complements to other fibers in various enteral
nutrition solutions. Plants with documented ability to boost resistance and decrease
vulnerability to disease, often referred to as chemopreventive agents, are usually
easily available, inexpensive to produce, rich in fibers, and have no or limited
toxicity. Among the numerous agents with chemopreventive abilities are a whole
series of phenolic and other compounds suggested to reduce the speed of aging
and often documented to prevent degenerative malfunctions of organs: isothiocya-
nates in cruciferous vegetables, epigallocatechin-3-gallate (EGCG) in green tea,
caffeic acid in coffee, capsaicin in hot chili peppers, chalcones in apples, euginol in
cloves, gallic acid in rhubarb, hisperitin in citrus fruits, naringenin in citrus fruits,
kaempferol in white cabbage, myricetin in berries, quercetin in apples and onions,
resveratrol and other procyanidin dimers in red wine, and various curcumenoids
found in turmeric curry foods, in addition to thousands of hitherto less explored or
unexplored substances. Turmeric, dried and powdered roots of the plant
Curcuma
longa
, is rich in natural antioxidants, and has proved to be a strong inhibitor of
proinflammatory messengers, such as NF-κβ, cyclooxygenase-2 (COX-2), matrix
mettaloproteinase-9 (MMP-9), inducible nitric oxide synthase (iNOS), TNF, IL-8,
eotaxin, cell surface adhesion molecules, and antiapoptotic proteins.
67
(See further
a recent review.
68
)
Chili pepper, a herb with high content of flavonoids (>100 mg/100 g), has recently
caught attention, especially since a specific receptor for its active substance, cap-
saicin, has been demonstrated and cloned.
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The cloning of the vanilloid receptor
1 (TBRV1) has opened a floodgate for discoveries regarding the function of this
complex molecule
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and provided explanation for earlier observed clinical effects of
intake of chili peppers. This receptor is associated with nociceptive afferent nerve
fibers and broadly expressed, especially in brain, epidermis, and visceral cells. Old
observations as well as recent studies suggest a great potential of antioxidant-rich
chili fibers for control the immune cells, both innate and acquired,
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of chronic dis-
eases especially diabetes, both type 1 and 2,
72,73
hypertension,
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and cancer,
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as well
as chronic pain conditions
76
and obesity.
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8.10 DIvErsITy IN MICrobIoTA For bArrIEr FuNCTIoN
The gut mucosa and microbiota are intimately joined in the maintenance of a
well-functioning barrier between the host and the external environment—see further
two excellent reviews.
78,79
The barrier is suggested to be composed of three barriers
in one: physical, innate immune, and adaptive immune. Emphasis has in the past
focused mainly on the physical barrier, but tends in more recent years to switch to the
importance of the innate immune mechanisms, particularly the role of antimicrobial
peptides, such as defensins and more recently angiogenins.
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