General Description
Cat's claw (Uncaria tomentosa), or una de gato, is a perennial,
woody vine that is native to Peru. Currently, it also grows throughout
Central and South America in countries such as Columbia, Panama,
and Ecuador. Its name is due to the claw-like thorns along the vine,
which help the plant adhere itself up to a hundred feet into the
limbs and trunks of trees. The vine seasonally produces yellowish-white
flowers. Most often the inner bark is harvested because it is believed
to contain the most healing properties.
Health applications
- Inflammation
- Immune health
History and traditional use
There are many known traditional uses of cat's claw. Several Peruvian
tribes use the plant to treat arthritis, rheumatism, asthma, inflammation,
gastric ulcers, cancer, to heal wounds, and as a contraceptive.
The Cashibo tribe of eastern Peru uses cat's claw to treat fevers,
abscesses, and to cleanse the digestive system. Other known indigenous
Peruvian uses include using the vine for hemorrhages, impurities
of the skin, as a blood cleanser, and for irregularity of the menstrual
cycle. Many contemporary claims about the healing powers of this
vine come from the numerous traditional uses of the plant. As yet,
scientific verification as to the legitimacy of these traditional
uses of cat's claw is minimal.
Chemical constituents
The active substances in cat's claw are oxindole alkaloids, quinovic
acid glycosides, proanthocyanidins, tannins, and several other
phytochemicals. Research has shown that there are two variant
alkaloid chemical types of Uncaria tomentosa which differ both
in their content and subsequent activity in the body. One chemical
type contains pentacyclic oxindole alkaloids, pteropodine, isopteropodine,
etc., which have a positive effect on the immune system. The other
contains tetracyclic oxindole alkaloids, rhynchophylline and isorhynchophylline,
which tend to counter the beneficial effects of the aforementioned
pentacyclic alkaloids.1
Inflammation
Cat's claw may inhibit inflammation. Plant sterols like beta-sitosterol,
acids, and other antioxidants may account for some of these properties.2
However, research also shows that phytochemicals called quinovic
acid glycosides, found in the bark and roots, may be the most
potent anti-inflammatory constituents in the plant.3,4
Immune health
Some alkaloids, called indole alkaloids, have been found to display
immunostimulating effects. The most attention to date has been
on indole alkaloids found within the bark of cat's claw. Studies
indicate these alkaloids increase immune function.5
The potential benefits of cat's claw as an immunostimulant, as
an anti-inflammatory, and its potential as an antimutagenic,
are not thoroughly documented. More clinical studies are needed
before its effects as a supplement are completely understood.
Dosage/Toxicity
Cat's claw can be taken in 1 to 2 ml tinctures up to 2 times a
day, as a capsule 350 to 500 mg once or twice per day, and as
tea, 1 g per cup, 1 to 3 times per day. The appropriate levels
of intake for optimizing the potential benefits of cat's claw
is not yet known. In both human and animal studies no toxicity
has been detected.6,7 Experts recommend that women
who are pregnant avoid taking cat's claw. |
