Uncaria tomentosa (Willdenow ex Roemer & Schultes) De Candolle

1. CLASSIFICATION

Kingdom: Plantae (Plants)

Subkingdom: Tracheobionta (Vascular plants)

Superdivision: Spermatophyta (Seed plants)

Division: Magnoliophyta (Flowering plants)

Class: Magnoliopsida (Dicotyledons)

Subclass: Asteridae

Order: Rubiales

Family: Rubiaceae (Madder family)

Genus: Uncaria Schreber, Gen. Pl.: 125. Apr 1789

Species: Uncaria tomentosa (Willd.) DC

Common Names: “cat’s claw”, “Peruvian cat’s claw”, “hawk’s claw”. Castilian/Spanish : Peru “uña de gato”, “uña de gato roja”; Loreto “garabato colorado”; Ucayali “uña de gato de altura”, “garabato amarillo”,“bejuco de agua”; San Martín “garabato”; Others “paraguayo”, “garabato”, “garabato casha”, “samento”, “toroñ”, “tambor huasca”, “uña huasca”, “uña de gavilán”, “garra de gavilán”, “saventaro”, “soga de agua”, “vilcacora”. Asháninka: kug-kukjagui. Portuguese : “deixa paraguayo”. Others: “unganangui”, “uncucha”, “tsachik”, “paotati-mösha”, “misho-mentis”, “jipotatsa”, “torõn”.

2. DESCRIPTION

Habit: Gigantic (very large) perennial liana (woody vine) that grows climbing around treesor creeping, with hook-like thorns that grow along the vine and resemble the claws of a cat. These claw-like projections allow the vine to attach to tree bark and also give the plant its name. The stem is reddish colored. This species can reach over 30 m high into the canopy and much more meters in length.

The stem of Uncaria tomentosa (Willd.) DC can reach several centimeters in diameter and contains a clear watery sap. The external bark has superficial longitudinal fissures, and the internal bark is fibrous, with the ground bark the color golden yellow. The sap is watery and astringent in taste. The terminal branchlets are quadrangular and yellow-green in color.

Uncaria guianensis, a closely related species, has thorns that are more curved.

Leaves: Simple, opposite, bright green, and dimorphic; oblong, oblong-ovate (oval-shaped) or elliptic. The hook-like thorns grow at the base of the leaves. The underside of the leaf has fine hairs. The leaf blade is 7.5 cm to 17 cm in length and 5 cm to 12 cm in width. The leaf margins are entire; apex is acute, or rarely acuminate; base is round and/or cordate (heart-shaped). The stipules are deltoid, 6 mm to 12 mm long and 4 mm to 8 mm wide. The spines are woody, occur in pairs, are slightly curved but straight, and pointy; 8 mm to 10 mm in length and 3 mm to 6 mm in width.

Flowers: The inflorescences occur in racemes or globular cymes, are axilary and/or terminal, 7 cm to 18 cm in length, 1.5 cm to 2.5 cm in diameter. Flowers are bisexual, actinomorphic and sessile. The calyx is gamosepalous, tubular, 1 mm to 1.5 mm in length and 0.8 mm to 1 mm in diameter. The corolla is gamopetalous, 7 mm to 13 mm in length, 3 mm to 5 mm in diameter, with 5 round lobes; yellow. Stamens are sessil; 5-fused to the throat. The anthers are oblong with prolonged and divergent bases; 1 mm to 1.2 mm in length and 0.3 mm to 0.4 mm in width. The stigma is ellipsoid, 0.5 mm in length, with linear 4 mm long styles; inferior ovary.

Uncaria guianensis, a closely related species, has reddish-orange flowers.

Fruit:The fruits are dry and dehiscent; elliptic capsules; 5 mm to 8 mm long and 3 mm to 6 mm wide.

3. ORIGIN, DISTRIBUTION AND ECOLOGY

Origin: Uncaria tomentosa (Willd.) DC is native to the Amazon basin, particularly to Peru.

Distribution: Uncaria tomentosa proliferates spontaneously all over the Amazon rainforest, especially in the upper Amazon region of Peru and neighboring countries, and other tropical areas of South and Central America, including Peru, Colombia, Ecuador, Guyana, Trinidad, Venezuela, Suriname, Costa Rica, Guatemala, and Panama. It has also been reported as far North as Belize, and South into Paraguay. Maranhao, Brazil, is the most Eastern area where Uncaria tomentosa has been reported to grow naturally. There are as many as 60 species related to this plant.

Uncaria tomentosa, which is used by Indian shamans, can be found on the mountain slopes in the jungle. It is most frequent in the Montaña in Peru.

In Peru, Uncaria guianensis (Aubl.) J. F. Gmel., a closely related species, has been reported in Amazonas, Ayacucho, Cuzco, Huánuco, Loreto, Madre de Dios, San Martín, and Ucayali.

Ecology: Uncaria tomentosa is a ligneous climbing plant that reaches full maturity after about twenty years of age. According to father Edmund Szelinga —a Polish Salesian missionary living 70 years in Peru— the best part for medicinal purposes is the bark or root of young Uncaria tomentosa which is around three years old. According to other authorities, for use in medicine, the bark is removed from the stems of Uncaria tomentosa vines that are over 8 years old.

The bark is just as efficient as the roots; therefore the underground parts of the plant should not be exploited, so that the plant can regenerate. The de-barked vines may be woven into rattan-like furniture.

Uncaria tomentosa as well as Uncaria guianensis are both, collected from the wild and cultivated. The best growing areas for Uncaria tomentosa are in the organic soils between 250 and 900 meters above sea level. Although both are difficult to cultivate, in some areas of Peru they are usually planted from cuttings of the vine rather than from seeds. When collected from the wild, they are cut 1 meter above the ground in order to leave the root undisturbed. The vine can grow back and reach maturity again in about four years. It can then be harvested again.

This plant is typical of primary forest, but is also found in disturbed forest and rarely in secondary forest.

4. HISTORY

Father Edmund Szeliga —an elderly Polish missionary living in Peru— cited by Rybiński and Warszewski (2000) on their book ‘Vilcacora, the Miracle Cancer Cure’ states “…the queen of all the healing plants of Amazon, vilcacora. Its Latin name is Uncaria tomentosa (Willd.) DC, while in Spanish it is ‘uña de gato’. It’s the Incas holy vine, whose use once was restricted to the current ruler and his closest family only. As early as the 1960s at the Naples University, a detailed chemical analysis was conducted at my commission, which showed that this plant has a completely unique composition of alkaloids and glycosides, which inhibits the growth of many varieties of cancer. The infusion from a few grams of desiccated vilcacora drunk three times a day in quarter of a liter doses proves to be an extremely successful remedy even at the advanced stages of the disease. This amazing plant opens up completely new perspectives for medicine!...”.

Uncaria tomentosa is still considered a sacred plant among the Ashaninkas and other indigenous Peruvian Amazonian tribes such as the Campa Indians. Actually, in the Amazon rainforest, there exist two closely-related species of Uncaria that are used almost interchangeably. They are Uncaria tomentosa and Uncaria guianensis , and both are called by the same common name, ‘cat’s claw’ or ‘uña de gato’. Sometimes, Uncaria tomentosa is called ‘uña de gato roja’ (red cat’s claw), and Uncaria guianensis, ‘uña de gato blanca’ (white cat’s claw), in order to differentiate them from each other. According to the Austrian investigator Klaus Keplinger (1999), these herbs serve as a means of "regulating the physical and spiritual worlds" for these tribal groups.

In other parts of Latin America, there exist several other species of plants with a common name of ‘cat’s claw’; however, they belong to totally different groups of plants other than the genus Uncaria and family Rubiaceae. In Mexico, for example, there exist several ‘cat’s claw’ species that have toxic properties.

From the perspective of ethnobotany, the higher a plant's status among native peoples, the more potent it often proves to be medicinally. Both, Uncaria tomentosa and Uncaria guianensis, have been being used by the indigenous peoples of the Amazon rainforest since ancient times for medical purposes. It has been estimated that these species of Uncaria have been used medicinally by the Aguaruna, Asháninka, Cashibo, Conibo, and Shipibo tribes of Peru for at least 2 000 years.

The earliest record of use of Uncaria tomentosa was related to the Asháninka Indian tribe in Central Peru. They continue using this plant until today and nowadays they are also the largest commercial source of Uncaria tomentosa from Peru.

The Asháninka Indians live further and deeper into the jungle than other tribes. All the other tribes learned from the Asháninkas about the unusual healing properties of Uncaria tomentosa long before Spanish colonization. The Asháninkas, just like the Incas did later, worshipped Uncaria tomentosa as a god, and called it kug-kukjagui. Uncaria tomentosa was to them the highest deity who gave rise to all other gods. This is why the Indians carved the images of their minor gods in the mature, ligneous shoots of Uncaria tomentosa. And because this is a long climbing plant, the gods, as you may find out when visiting any museum devoted to the Indians of the forest, have very long profiles and oval faces (Rybiński and Warszewski, 2000).

Asthma, inflammations of the urinary tract and recovering from childbirth are some of the conditions they treat with the decoction of this plant. The Asháninka also use Uncaria tomentosa as a kidney cleanser, to cure deep wounds, for arthritis, rheumatism, and bone pain. Control of inflammation and gastric ulcers as well as treatment for cancer are also some of the uses the Asháninka assign to this plant.

This Peruvian ethnic group, as well as several other different ones, have also been using Uncaria tomentosa as a contraceptive. Dr. Fernando Cabieses, M.D., a noted authority on Peruvian medicinal plants, has reported that the Asháninka boil 5 to 6 kilograms of the root in water until it is reduced to little more than 1 cup. This decoction is then taken 1 cup daily during the period of menstruation for three consecutive months, which supposedly causes sterility for three to four years.

In Piura, a region in the Peruvian coast, indigenous tribes use Uncaria tomentosa to treat tumors, inflammations, rheumatism, and gastric ulcers.

Other Peruvian indigenous tribes use Uncaria tomentosa to treat diabetes, urinary tract cancer in women, hemorrhages, menstrual irregularity, cirrhosis, fevers, abscesses, gastritis, rheumatism, inflammations; for internal cleansing and tumors; and to normalize the body.

In Colombia, some Indian tribes use Uncaria tomentosa to treat gonorrhea and dysentery.

In Suriname, the decoction of Uncaria tomentosa is used against dysentery, intestinal affections and wounds.

In England, some companies are offering massage creams with Uncaria tomentosa. They are also marketing toothpaste of Uncaria tomentosa to prevent and cure periodontosis, soaps based on Uncaria tomentosa as an anti-mycotic with supposed fungistatic activity, recommended for excessively sweating skin. A shampoo is also sold, recommended for patients with allergic reactions, psoriasis, sensitive to detergents and susceptible to hair loss. A hair conditioner as well as an antiseptic and antimycotic talc as a preventive for mycosis and eczema are also commercialized.

Due to its many curative properties, Amerindians consider Uncaria tomentosa a kind of panacea —a cure for anything—. The most traditional Ashaninkas always carry a kind of bag or basket woven from some flexible forest bark. The Indians from the jungle use these bags to carry Uncaria tomentosa a plant which they never part with, a plant that accompanies them in whatever they do.

Although its uses by native healers have been known for over fifty years, it was not until Keplinger began studying the properties of ‘uña de gato’ in 1974 that it began to receive attention for its potential medicinal value. A 1999 systematic review paper by Keplinger et al . described an analysis of 55 works summarizing ethnomedical and pharmacological uses.

The first scientifically controlled studies on Uncaria tomentosa were performed in the early 1970s when Klaus Keplinger, a journalist and self-taught ethnologist from Innsbruck, Austria, organized the first definitive work on Uncaria tomentosa. Attracted by the several ethnologic reports that documented the many uses of this tropical vine, Keplinger worked with this plant for several years. His work eventually led in the early 1990s to the marketing of several extracts of Uncaria tomentosa in Austria and Germany as herbal drugs with immunomodulating properties (Keplinger et al., 1999; Gabriel et al., 1999). He also filed four U. S. patents describing extraction procedures for a group of chemicals called oxindole alkaloids, and the immunostimulating actions of these alkaloids, found in this plant.

Keplinger’s studies on Uncaria tomentosa and its novel oxindole alkaloids called worldwide attention in the medicinal properties of this valuable vine of the rainforest. Consequently, several other independent researchers in Spain, France, Japan, Germany and Peru confirmed Keplinger’s results. Since mid-1990s, some Peruvian physicians are investigating the use of the extract of Uncaria tomentosa, complemented with other herbal drugs, in order to treat AIDS.

Many of the studies published after Keplinger’s work confirmed the immunostimulating properties of the alkaloids in the bark and roots. The whole oxindole alkaloid fraction, whole Uncaria tomentosa bark and/or root bark extracts, and six individually-tested oxindole alkaloids increased immune function by up to 50% in relatively small amounts.

In 1998, independent Peruvian researchers demonstrated that a whole extract of Uncaria tomentosa increased immune function in rats at a dosage of 400 mg/kg. In 1999, independent Canadian researchers at the University of Ottawa reported that a whole Uncaria tomentosa extract demonstrated a strong immunostimulant effect.

Since 1999, several patented extracts of Uncaria tomentosa have been manufactured and marketed in the United States and other developed countries. Clinical studies funded by private companies continue to be carried out; these studies show that the immunostimulating benefits of Uncaria tomentosa claimed by Amazon indigenous tribes have a scientific support.

In the last years, the presence of Uncaria tomentosa —the ‘original cat’s claw’ species— has declined in the Peruvian rainforest by overharvesting due to sustained market demand. This species is getting harder for wild harvesters to find.

Today, the lower-growing and easier to find Uncaria guianensis is commonly found in many large lots of Uncaria tomentosa bulk material being exported out of South America. Although it is easy to tell which is Uncaria tomentosa  and which Uncaria guianensis if one can see the claws or hooks —the hook shapes are different; even, the leaves of the Uncaria tomentosa species are also more hairy than those of Uncaria guianensis— these species are literally indistinguishable after they have been harvested (unless subjected to chemical analysis). And during harvest, leaves and hooks are sometimes 30 meters above ground in the canopy and obscured by other vegetation (it is only the lower vine that is cut off in harvesting, whereas the upper vine is discarded in the top of the canopy where it is wound around everything). By the time it arrives to the marketers, there is no way to tell if the inner bark is Uncaria tomentosaor Uncaria guianensis

Uncaria tomentosa generally grows at higher elevations than Uncaria guianensis, which grows at river level. This means that Uncaria guianensis is easier to find, easier to get to, easier to harvest and easier to transport (because it grows near to the rivers).

The effect of this substitution on the medical properties is still unknown, although independent phytochemical analysis shows, however, that both plants contain most all of the same phytochemicals (including alkaloids), just in different ratios. Further information is required.

Market demand for ‘cat's claw’ has increased dramatically in the past 10 years, and a huge amount of Uncaria tomentosa has been harvested out of the Peruvian Amazon and exported out of Peru. Brazilian harvesters have entered the market in the last five and are exporting as well.

In an age of emerging new viruses with stunning virulence, natural antiviral and immunomodulating substances such as those from Uncaria tomentosa could play a significant role in human disease prevention and treatment. Several institutions in Peru, Austria, Germany, Great Britain, Italy, Switzerland and the United States, among other countries are conducting today detailed research in Uncaria tomentosa.

Legend: How the Asháninkas where taught about Uncaria tomentosa

Taken from the book ‘Vilcacora, the Miracle Cancer Cure’, by G. Rybiński and R. Warszewski (2000)

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Tasurinchi was the first Ashaninka. He was the Indian Adam. He did not have a wife at that moment, because initially he was alone in the world, and this is why he had to cook, and wash, and hunt on his own. Tasurinchi’s life was horrible. He toiled away at tasks without number, and there was no one to help him. His legs hurt from constant chasing of animals. His hands hurt from stringing beads for necklaces. His head hurt from constant thinking about how to cope with all his chores.

One day he met a puma as he was walking, or actually running, through the forest.

— ‘I have a stomach-ache,’ — he complained.

— ‘Why?’ — the puma was surprised.

— ‘Because the food I had yesterday wasn’t fresh, I guess. Maybe you know, dear puma, what I should do?’

The puma approached a tree, reached for a thick liana that was entwined around it, and tore off some bark with its claws.

— ‘Suck it under your tongue’ — the puma advised Tasurinchi —‘This

will help you.’

— ‘What is it?’ — he asked.

— ‘How come you don’t know? It’s kug-kukjagui (cat’s claw)’.

Tasurinchi listened to the puma and his stomach stopped aching after a moment. But what of it, if his head still hurt. ‘I have handled the stomach somehow. What should I do to get rid of this horrible pain in my head?’ he wondered and kept on running. He must have covered some kilometer when he met a capybara that was heading towards the river.

— ‘I have an awful headache,’ —he said to the rodent, instead of ‘Good morning’. ‘Don’t you know, dear capybara, what could help me?’

The capybara approached a trunk that was entwined with some plant, and scraped some rustcoloured powder off the strong stem with its knife-sharp teeth.

— ‘Dissolve this in water and drink it,’ — said the animal. — ‘You will forget the headache in a moment.’

— ‘What is it?’ asked Tasurinchi.

— ‘How come you don’t know? It’s kug-kukjagui (cat’s claw).’

Tasurinchi prepared the decoction just as the capybara had advised him and drank it with a grimace because it was bitter. Before he managed to think that he should move on, he realised his head did not hurt any more. ‘Very good,’ he thought. ‘Excellent! Fantastic! But what of it, if the wound on my hand I had inflicted on myself when forcing my way through the thickets still smarts...’. A tapir came along from across the way.

— ‘Hello, tapir!’ — exclaimed Tasurinchi. — ‘My friend, maybe you could advise me how I should dress this smarting wound?’

The tapir sniffed around for a while with his long nose, and then approached a tree that was clad with some kind of ivy. The tapir hit the thick stem a few times with its hoof, tore off a piece of the bark and passed it to Tasurinchi.

— ‘Make a dressing of this bark,’ — said the animal. — ‘Surely, this will help you. I always dress my hoof with kug-kukjagui (cat’s claw) whenever I hurt it. We animals have long known this tried out and tested way...’

— ‘Is this kug-kukjagui (cat’s claw) as well?’ — Tasurinchi was surprised.

— ‘Why, don’t you recognize it?’

— ‘Could you tear off another piece for me?’ — asked Tasurinchi, who suddenly realized that he had probably found the solution to all his problems. ‘I’m in a hurry and I won’t have time to stop, and I would very much like to have some of this bark for later...’

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5. UTILITY

Parts Used: Bark, root, leaves.

· Bark: The part used medicinally is the inner bark of the vine from which a boiled decoction is made or extracts produced. The inner bark of Uncaria tomentosa (Willd.) DC contains up to 0.5% Pentacyclic Oxindole Alkaloids (POA).

· Roots: Although the traditional part used as medicinal is the bark, in recent years, extracts of the root have also been prepared commercially. It has never been, however, proven scientifically that the root or the root bark contains more alkaloids than the vine bark. In fact, independent lab analysis over the years shows the vine bark contains an equal or greater percentage of alkaloids than the root and/or root bark, although there are contradictory results.

· Leaves: Some companies are marketing pulverized leaves of Uncaria tomentosa. This powder can be used in order to prepare an infusion the same way as the bark or root is used. The leaves contain higher levels of Pentacyclic Oxindole Alkaloids than the stem bark.

Properties:

Uncaria tomentosa is used as:

analgesic

antibacterial

anticancerous

anticoagulant

antidepressant

antidysenteric

antihypertensive

anti-inflammatory

antileukemic

antimutagenic

antioxidant

antiproliferative

antitumorous

antiulcerous

antiviral

blood cleanser

bowel cleanser

bowel protector

cicatrizant

contraceptive

cytoprotective (cellular protector)

cytostatic

cytotoxic

depurative

detoxifier

diuretic

gastrototonic

general daily tonic

hypocholesterolemic

hypotensive

immunomodulatory

immunostimulant

non-specific immuno-modulating agent in viral illnesses and cancer

stomach protector

tonic

ulcer preventative

vulnerary

Uncaria tomentosa is used for:

acne

adjunctive therapy for cancer (to reduce chemotherapy side effects and protect cells)

allergy

arthritis (all kinds)

arthrosis

asthma

bone pains

bowel problems

cancer

cerebral ischemia (possible prevention)

chronic inflammation of all kinds

chronic viral infections

cirrhosis

colitis

Crohn's disease

cyst

depression

diabetes

diarrhea

disease prevention

diverticulitis

dysentery

dysmenorrhea (disturbances of the menstrual cycle)

environmental poisoning

fevers

gastric ulcers

gastritis

gonorrhea

hemorrhages

herpes zoster

IBS

immune disorders

inflammation of joints

inflammations

intestinal affections

kidney cleanser

menstrual irregularity

muscle pains/strains/injuries

neuralgias

osteoarthritis

prevention of radiation damage

prostatitis

rheumatic disorders

rheumatism

rheumatoid arthritis

skin disorders

stomach

stomach ulcers

stomatitis

tumors

ulcerative colitis

ulcers

urinary tract disorders

viral and bacterial co-infections in AIDS

viral diseases

wounds

Although there exist several proprietary extracts in the market, many authorities believe that the best way to profit of Uncaria tomentosa is preparing a natural vine bark decoction. They recommend to get some good quality vine bark and boil it in water in order to obtain a concentrated decoction, which is the traditional way the Amazonians use this amazing plant, with all the natural chemicals that nature provides in the proper ratio. They argue that the invasive ‘purification’ techniques may only extract one particular type of chemical, or change the complex ratio of naturally-occurring chemicals in herbal systems, which ignore the natural synergy of the plant chemicals.

Immune System

There are a number of parallels between plant immunological activity and the immune systems of mammals, including adaptive mechanisms for viral resistance. In order to adapt to environmental aggressions, plants produce a vast number of natural products that have antimicrobial and immunomodulating potential.

The human immune system is a highly complex and extraordinarily sophisticated mechanism involving both innate and adaptive responses. In the last years, basic research on how natural substances extracted from plants affect immune response has led to the discovery of several tropical plants such as Uncaria tomentosa, which has gained popularity as a natural immunostimulant and immunomodulating agent.

Plants from tropical rainforests represent a rich source of potential immunomodulating substances. Immunomodulating activity refers to biological or pharmacological effects of compounds on humoral or cellular aspects of the immune response.

In a 1998 British narrative review paper, Syrimis magazine concluded that the broad therapeutic application of Uncaria tomentosa suggests it is a worthy addition to the list of drugs used to treat the immune system.

In one study (Flores, 1999), Uncaria tomentosa showed an increase in phagocytosis. In other in vivo Peruvian study, Mestanza (1999) found that phagocytosis was increased in rats when an extract of Uncaria tomentosa was administered at a dose of 400 mg/kg. The strengthening of phagocytosis in turn heightens the organism’s self-defense.

Independent research performed on whole oxindole extracts and whole root or vine extracts of Uncaria tomentosa reports the presence of two types of alkaloids in the extracts. These are the pentacyclic oxindole alkaloids (POA) and the tetracyclic oxindole alkaloids (TOA). Both of them showed immune stimulant actions.

Monocytes and granulocytes, under the influence of these alkaloids, take over the function of macrophages, cells attacking viruses and bacteria. It was noticed that after patients had taken the infusion of Uncaria tomentosa for a week, the monocytes’ activity rose by about 50%. The erythrocytes’ resistance to damage grew as well. This means in practice that the crisis is over and that the organism is beginning to get better.

Some commercial companies that market patented formulas extracted from Uncaria tomentosa argue that this plant produces ‘good alkaloids’ and ‘bad alkaloids.’ According to studies funded by them, the ‘good ones’ are the pentacyclic oxindole alkaloids (POA) which are reported to induce a yet unknown immune regulating factor (Muhammad et al., 2001) and the ‘bad ones’ are the tetracyclic oxindole alkaloids (TOA). A 1998 study showed that pentacyclic alkaloids weakly activated human B- and T-lymphocytes, and that tetracyclic oxindole alkaloids reduced the activity of pentacyclic oxindoles (Wurm et al., 1998).

Presumably, the bad alkaloids counteract the immune benefits of the good alkaloids. The presence of as little as 1% tetracyclic oxindole alkaloids content in an Uncaria tomentosa formulation would diminish the immunostimulant effect of the formulation by as much as 30%. However, this hypothesis has not yet been confirmed by independent laboratories, and there are only two studies reporting that, both of them funded by or performed by the only company selling a TOA-free Uncaria tomentosa product.

The company that funded these studies is marketing standardized extracts of the root of Uncaria tomentosa containing a minimum of 1.3-percent pentacyclic oxindole alkaloids free of tetracyclic oxindole alkaloids.

Some scientists have proposed that the supposed ‘bad alkaloids’ are not such. Instead, they think that the overexploitation of Uncaria tomentosa has led the indigenous peoples of the Amazon who collect the plant from the wild to turn to Uncaria guianensis, a species that is easier to find and collect. Indeed, today Uncaria guianensis is a common ‘contaminant’ in many large lots of Uncaria tomentosa bulk material exported from South America. Although the phytochemical makeup of both species is similar, the ratio of oxindole alkaloids could be different.

The immunomodulating activity of Uncaria tomentosa includes suppression of NF-kappa B (Sandoval et al., 2000), enhancement of B- and T-lymphocytes, stimulation of phagocytosis (Wagner, 1985), and enhancement of interleukin-1 and interleukin-6 (Lemarie et al., 2000).

According to Pero (2000), the whole plant extract is considered a non-specific immunomodulating agent and may be used synergistically with antioxidant therapy.  According to Dr. Klaus Keplinger, holder of several patents on Uncaria tomentosa from the Austrian laboratory Immodal, this plant is exceptionally useful in general stimulation of the immune system, and in multiplying the defensive strength of the organism.

Finally, it is important to notice that, with a few exceptions, the majority of studies have been in vitro or in animal models, with weak to moderate immunomodulating and antiviral effects. As Williams (2001) says, “…There is no overwhelming evidence to support the public perception of this herb as a potent immune stimulant, although it appears to be a beneficial and safe, non-specific immunomodulating botanical. Further research, both in the laboratory and clinically, is warranted…”.

Cancer

Traditionally, the indigenous peoples of the Amazon have been using Uncaria tomentosa to treat cancer. In the upper Amazon, a decoction of the bark of Uncaria tomentosa is mixed with resin of Croton lechleri Müll. Arg., an herbal product with recognized potent cytotoxicity against cancer cells, to treat several kinds of cancer. Western medicine in Peru and Europe started to use extracts of Uncaria tomentosa as an adjunctive treatment for cancer in the early 1990s.

Some in vitro anticancerous properties have been documented for the raw extract of Uncaria tomentosa as well as oxindole alkaloids and other constituents in the extract. Five of the oxindole alkaloids have been clinically documented with in vitro antileukemic properties, and various root and bark extracts have demonstrated antitumorous and antimutagenic properties.

Uncaria tomentosa has the ability to stop and reverse very advanced pathology, and, what is also important, its application does not exclude the continuation of therapy with the use of the methods of traditional medicine. In the 1980s, Keplinger observed that cancer patients receiving traditional cancer therapies such as chemotherapy and radiation reported fewer side effects (such as hair loss, weight loss, nausea, secondary infections, and skin problems) to the traditional therapies when they were treated with extracts of Uncaria tomentosa.

Dr. Julie Clements, oncologist from the United States, affirms (cited by G. Rybiński and R. Warszewski, 2000): “There has been a substantial decrease in the side-effects of radiation treatment and chemotherapy with respect to my patients suffering from malignant diseases who have been treated with Uncaria tomentosa. On the basis of a few years’ clinical practice, I also know that applying Uncaria tomentosa, may be compared in terms of its effects to remission, i.e. the disappearance of tumors, including substantially large tumors. With time, I have come to like Uncaria tomentosa so much that I have had my mother use it.”

Subsequent studies have shown that the extract of Uncaria tomentosa can aid in DNA cellular repair and prevent cells from mutating, which might explain why the extract allows cancer patients to better tolerate chemotherapy and radiation. Besides, these studies have also reported that the extract of Uncaria tomentosa can help prevent leukopenia (a common chemotherapy side effect consisting in lossing of white blood cells) and immune damage caused by many chemotherapy drugs.

According to Peruvian Dr. Victor Incháustegui, however, plant therapy should not be used during radiotherapy and chemotherapy. He recommends maintaining a three-day interval between chemotherapy or radiotherapy and phytotherapy, and vice versa. The results are particularly favorable if such a time sequence is observed.

In 1993 at the Instituto de Medicina Tradicional (IMET, Institute of Traditional Medicine) Dr. Teodoro Cerruti and others separate from Uncaria tomentosa the alkaloids isopteropodine, pteropodine, isomitraphiline, unkarine, mitraphiline, and speciophiline. Colonies of leukemia, HL-60 and U-937, were subjected to their effect.

After the colometric tests with the use of agar-agar, the slowing-down effect on colonies of leukemia cells of alkalis separated from Uncaria tomentosa appeared to be clear and measurable. Various concentrations of alkalis were used in that experiment and their effect lasted up to the seventh day after the experiment had finished.

Moreover, through colometric and spectrophotometric analyses, the survival ability of pathological cells and the number of colonies of HL-60 and U-937 cells were assessed. They obtained the following results: It was stated that isopteropodine, pteropodine, isomitraphiline, unkarine and speciophiline alkalis have a strong inhibitory, i.e. slowing-down, effect on the growth of leukemia cells from the HL-60 and U-937 lines. This appeared to be directly proportional to the dose of alkalis administered during the experiment.

The most effective alkali here is unkarine F. In its case the value of IC-50 was achieved, which means that this substance has reacted to at least 50% of leukemia cells, which, in turn, in clinical experience means the beginning of the illness’s regress. Unkarine F worked selectively and was able to differentiate between pathological and healthy cells. Thanks to this it did not inhibit the growth of healthy cells produced in the bone marrow. To sum up, it can be said that unkarine F, derived from Uncaria tomentosa, can be regarded as a strong drug which is effective against leukemia.

Several studies also at the Instituto de Medicina Tradicional, Iquitos, Peru, performed on animals, have shown that Uncaria tomentosa heightens the capacity of the immune system to react to cancerous cells. The experiments conducted there show the particular efficiency of Uncaria tomentosa in overcoming breast, prostate, lung and stomach tumours.

Dr. Cerruti, however, notices that not every disease that they can cure in the case of rats is, with the use of similar methods, equally curable in the case of people. Although they have obtained very interesting results from the research conducted on animals, these results are not definitive.

In 1998, a scientific Swedish team reported that the extract of Uncaria tomentosa inhibited the growth of lymphoma and leukemia cells in vitro.

In 2001, a medical Italian team reported that some extracts and their chromatographic fractions from the bark of Uncaria tomentosa directly inhibited the growth in vitro of a human breast cancer cell line MCF7 by 90%. Their data indicated that, in addition to the antimutagenic activity, Uncaria tomentosa extracts and fractions exert a direct antiproliferative activity on MCF7. The bioassay-directed fractionation from barks and leaves resulted in the isolation of two active fractions, which displayed an IC50 of 10 mg/ml and 20 mg/ml, respectively and an antiproliferative effect, with about 90% of inhibition at a concentration of 100 mg/ml. Moreover, another team reported that it inhibited the binding of estrogens in human breast cancer cells in vitro.

Dr Richard Geber, author of the best-seller book ‘Vibrational Medicine’, assures that Uncaria tomentosa decreases the effects of radiation treatment and chemotherapy, which are inevitable when treating new growth tumors with conventional methods.

In their book, G. Rybiński and R. Warszewski (2000) cite four studies related to Uncaria tomentosa and cancer. i) In a group of three patients suffering from colon and ovary cancer, the new growth tumor disappeared in two cases after 4 and 7 months and became substantially smaller in one case. ii) In a group of twenty-two patients suffering from various varieties of new growth tumors, there was remission in 13 cases, i.e. the tumor disappeared, and the other patients lived longer than 5 years. iii) In the most numerous group of seventy-eight patients suffering from brain cancer, the disappearance of the tumors was observed with respect to all patients after a year. iv) In other clinical examinations where the efficiency of Uncaria tomentosa was tested with respect to three women of 42, 58, and 80 years of age suffering from ovary, uterus, and colon cancers, an amazing improvement was observed in all cases, including the disappearance of the tumors. These authors do not mention, however, the sources of these results.

Finally, in an online article by the Center for Alternative Medicine Research in Cancer ( www.sph.uth.tmc.edu/utcam/therapies/cat/htm) they concluded that, although the results of the 43 studies carried out in Uncaria tomentosa reviewed by them were very positive in terms of cancer regression, they did not provide substantial information on use in cancer and were not well documented.

Anti-inflammatory

In any kind of lesion, from the shortest cut in a finger to burnings and chronic affections such as arthritis and Alzheimer, there is an inflammatory process involved. This process is natural and allows the lesions to cicatrize.

Traditionally, the Asháninka Indian tribe in Central Peru uses a decoction of Uncaria tomentosa to treat inflammations of the urinary tract. They also use it to control inflammation related to arthritis and rheumatism. In order to treat arthritis, they sometimes use Uncaria tomentosa in combination with other local herbs such as chuchuhuasi bark.

In Western countries, Uncaria tomentosais included in some herbal combination remedies, e.g. with capsaicin in the arthritis cream, Nikken Anti-Arthritis. Some Essiac tea mixtures now contain Uncaria tomentosa in addition to the four traditional ingredients (burdock root, sheep sorrel, turkey rhubarb root and slippery elm bark).

Other Peruvian Indian tribes also use a water extract of Uncaria tomentosa in order to treat inflammations such as gastritis (stomach inflammation), arthritis (joint inflammation) and other types of inflammatory stomach and bowel disorders.

The anti-inflammatory effect of the water extract of Uncaria tomentosa can be understood by means of some plant sterols (beta-sitosterol, stigmasterol, and campesterol) with well-known anti-inflammatory properties found in this extract. Additionally, in 1991 a group of novel phytochemicals found in the bark and roots of this plant (called quinovic acid glycosides) had been documented with anti-inflammatory properties. Even more, these new phytochemicals have been reported with the most potent anti-inflammatory effect among all the constituents known in the plant. Some antioxidant chemicals (catechins and procyanidins) found in the extract also contribute to the anti-inflammatory properties.

Several subsequent in vivo and in vitro studies determined that the water extract of Uncaria tomentosa —and, especially, its glycosides— could inhibit inflammation up to 89%.

In 2000, a study by Sandoval et al. related to the antioxidant properties of the water extract of Uncaria tomentosa concluded that the extract is not only an antioxidant but also a remarkably potent inhibitor of TNF-alpha production. He stated “… The primary mechanism for cat's claw's anti-inflammatory action appears to be immunomodulation via suppression of TNF-a synthesis."

TNF-alpha (tumor necrosis factor - alpha) is a powerful molecule that initiates an inflammatory process. This protein also allows the recruiting of some specialized cells of the immune system called macrophages.

TNF represents a model for tumor growth driven by an inflammatory cytokine. Some researches reported that the primary mechanism for the anti-inflammatory action of Uncaria tomentosa appears to be immunomodulation through the suppression of this cytokine.

Water decoction of Uncaria tomentosa have been traditionally used by Amazonians in order to treat arthritis and rheumatism. According to Dr Richard Geber, author of the best-seller book ‘ Vibrational Medicine’, this plant has very low toxicity, and thus may be applied against arthritis even for a longer period of time.

Surprisingly, a patented product comprised of mostly alkaloids showed only modest benefit to arthritis patients. However, in 2002, scientists from the United States reported that the anti-inflammatory actions of Uncaria tomentosa are not attributable to immunostimulating alkaloids. This would explain why the tested commercial formula was scarcely effective against arthritis.

Other results from animal studies and reports of human cases show that taking Uncaria tomentosa by mouth has anti-inflammatory effects for individuals with either osteoarthritis (degeneration of joint components) or rheumatoid arthritis (an autoimmune disease in which the body’s immune system attacks cartilage and synovial fluid in joints).

On the other hand, Uncaria tomentosa appears to have little or no effect on swelling associated with arthritis, but study participants who took it reported less pain during exercise. However, few human studies have been conducted and results have not all been positive. More research is needed before Uncaria tomentosa may be recommended for treating arthritis.

Recent researches suggest that the water extract of Uncaria tomentosa might be helpful to people with Alzheimer's disease. The reasons for this are not clear. Some authorities think that this probable property could be related to the anti-inflammatory effect of the water extract of Uncaria tomentosa; some others believe that it could be related to the antioxidant effects already confirmed. However, a dilation of peripheral blood vessels in the brain by alkaloids such as rhynchophylline has also been proposed as a possibility. Moreover, Uncaria tomentosa has been demonstrated to retard the deposition of amyloid-beta protein.

Finally, it has been suggested that the extract of Uncaria tomentosa may protect against gastrointestinal damage associated with nonsteroidal anti-inflammatory drugs such as ibuprofen.

AIDS

Uncaria tomentosa has been used in Peru and Europe since the early 1990s as an adjunctive treatment for AIDS, as well as other diseases that target the immunological system.

Uncaria tomentosa was used to treat AIDS for the first time in Peru. Peruvian physician Roberto Incháustegui Gonzáles, who was president of the Comité de SIDA y Enfermedades de Transmisión Sexual (Committee of AIDS and Venereal Diseases) of the Instituto Peruano de Seguridad Social (Peruvian Institute of Social Security) at Iquitos, was the first professional who used experimentally the bark of Uncaria tomentosa in combination with the rhizome of Dracontium loretense K. Krause to treat AIDS.

Dr. Incháustegui’s research from 1989 to 1993 came to light in a series of newspaper articles, but it has never been formally published in a scientific journal. During his research, he administered an extract of the two mentioned plants to his patients with amazing results.

Dracontium loretense K. Krause “sacha jergón” is a well-known antiviral species and was administered as a rhizome extract. A decoction of the bark of Uncaria tomentosa was used as immunostimulant. Dr. Incháustegui used indistinctly Uncaria tomentosa and Uncaria guianensis

According to Dr. Incháustegui, most of his patients treated with this mixture resulted negative for AIDS virus after six months of treatment, on average. However, until date Dr. Incháustegui has not published any clinic results in any serious medical journal. In spite of that, this mixture continues being used in Peru —and since the late 1990s in Eastern Europe— to treat AIDS and herpes zoster.

Father Edmund Szeliga —a Polish Salesian missionary living in Peru for 7 decades and a self-taught phytotherapist — affirms have had several cases of AIDS cured using Uncaria tomentosa among other plants (Rybiński and Warszewski, 2000). He states “…It means that those patients with full symptoms of AIDS – not just those who were seropositive – after the treatment the density of viruses in the blood was lowered to such an extent that they were virtually impossible to detect. We do not say that the viruses disappeared entirely. We are cautious. We only state that their number fell to beneath vestigial amounts...”. He also asseverates that this is a permanent state and his observations indicate that the number of viruses does not increase again after a while. His observations have never been published in any medical journal and he also admits that he does not use control groups.

Scientists at the Instituto de Medicina Tradicional (Institute of Traditional Medicina), Iquitos, Peru, obtained very good results in retarding the growth of in vitro HIV viruses. This encouraged the commencement of volunteer testing. The results were more than just promising. After a few weeks of taking the Uncaria tomentosa infusion, the patients’ level of the HTLV virus dropped so significantly that it became hardly detectable. At the same time the number of CD4 lymphocytes rose. This proves that the functioning of the organism’s immune system, which had been disturbed by illness, is being restored.

Circulatory system

Several different phytochemicals found in the water extract of Uncaria tomentosa have demonstrated different actions in the blood and heart.

Some alkaloids contained in the extract have demonstrated hypotensive and vasodilating properties. These alkaloids are rhynchophylline, hirsutine, and mitraphylline.

Rhynchophylline also has shown to inhibit platelet aggregation and thrombosis. This compound was tested for a few years at the School of Chinese Traditional Medicine in Shanghai. The analyses conducted there show that rhynchophylline has the ability to inhibit the accumulation of platelets and may also prevent and reduce blood clots in blood vessels and relax the blood vessels of endothelial cells, dilate peripheral blood vessels, lower the heart rate, and lower blood cholesterol. Three sterols —beta sitosterol (80%), stigmasterol, and campesterol — have been identified and proven to be mild inhibitors of cholesterol synthesis in vitro (Field et al., 1997).

 This also means that could help to prevent atherosclerosis, inhibiting the formation of the atherosclerotic plaque that occurs during the progression of atherosclerosis.

Various chemicals in it are known to promote the loss of water from the body, relax smooth muscles, and widen small blood vessels in the hands and feet. All these effects may help to lower blood pressure.

It has also been proposed that the water extract of Uncaria tomentosa could help prevent strokes, diseases of the circulatory system, and heart attacks (due to its lowering C-reactive protein level activity).

Chronic and Occasional Asthma Prevention

In order to treat chronic and occasional asthma, a three-step herbal treatment has been proposed with good results. In the first step, a decoction of manayupa (Desmodium mollicum), a cleansing herb, is administered to cleanse or detoxify the body. In the second step, a decoction of two curative herbs, asmachilca (Eupatorium triplinerve), and mullaca (Muehlenbeckia vulcanica) is administered; these herbs diminish the hyperactivity and inflammation of the respiratory mucous membrane and fluidize bronchial secretions. During the third step, a decoction of the stem bark of Uncaria tomentosa is administered as a preventive herb.

Effectively,Uncaria tomentosa is known for its immunostimulating action (increase the organism's defenses) which contributes to prevent the asthmatic crisis. It has also anti-inflammatory properties which counters the bronchial edema. A study on 100 bronchial asthma patients treated with these medicinal plants was carried out at the Peruvian Institute of Phytotherapeutic Research in Lima between 1988 and 1991. Cleansing, curative, symptomatic and preventive plants were administered to 51 male and to 49 female patients with good results.

Antiviral

The water extract of Uncaria tomentosa has also shown in vivo antiviral properties. The same glycosides that have shown anti-inflammatory properties have also shown antiviral properties.

A mixture of an extract from the bark of Uncaria tomentosa and the rhizome of Dracontium loretense K. Krause “sacha jergón” has been proposed as a treatment against herpes zoster.

Uncaria tomentosa is also a promising source of systemic broad-spectrum antivirals that may cause less damage to host cells infected by chronic viruses than do pharmaceuticals.

Uncaria tomentosa also increases the production of leukocytes, and particularly the lymphocytes T4, which fight many viral diseases.

Antiviral activity of quinovic acid glycosides from Uncaria tomentosa has also been analyzed (Aquino, Simone, and Pizza, 1989).  An inhibitory effect against vesicular stomatitis virus was evident for all the nine compounds tested, although at relatively high concentrations with respect to the toxic dose. In other words, the antiviral activity was weak unless you approach the point where the herbal components would kill the cells as well.  The authors also showed that almost all these quinovic acid glycosides were inactive against rhinovirus type IB infection.

Digestive Tract

Traditionally, a water decoction of the bark and root of Uncaria tomentosa has been used in several regions of South America to treat stomach and intestinal affections, such as ulcers, dysentery, gastritis, etc.

The extract of Uncaria tomentosa can also be considered as a gastrointestinal decongestionant. It has the ability to cleanse the entire intestinal tract. Its effectiveness has also been proven in treating stomach and bowel disorders, such as Crohn's disease, leaky bowel syndrome, ulcers, gastritis, diverticulitis, irritable bowel syndrome, and other inflammatory conditions of the bowel, stomach, and intestines.

In an in vivo rat study, the water extract of Uncaria tomentosa was shown to be effective against stomach ulcers. Dr Brent Davis, a doctor who has been using Uncaria tomentosa for years in clinical practice in the USA considers that this climbing plant is an excellent medicine for many diseases, among other things, diseases of the digestive system. This plant has a phenomenal predisposition towards cleansing of the whole digestive tract, which is important because, as many doctors claim, “… death begins with the intestines, in the colon, to be more precise…”.

Dr. Davies also considers that in Western countries we consume food of such composition and consistency that it hinders excretion from the organism. “…With age and the organism growing flaccid, mini-hernias form in the colon, where the substances that are normally designed for excretion accumulate. When they get there they wedge and remain too long, and systematically contaminate the circulation of blood instead of leaving the organism. Uncaria tomentosa, however, prevents this - it cleans all depressions throughout the whole intestine. Who knows if this is not the most important, most blessed, of its workings?...”, he argues.

The depressions Dr. Davies refers to are called diverticula. Diverticula form in elder people, especially in developed countries, and is due to the diet scarce in fiber. These depressions, similar to fingers of gloves, can be filled with fecal matter, which accumulates for a long period of time and host many kinds of bacteria. These bacteria can infect the human tissue of the intestines and cause an inflammation called diverticulitis.

Apart from this, as has been found out, Uncaria tomentosa is helpful in treatment of the Crohn’s disease, the inflammation of the colon (colitis), and hemorrhoids, and also prevents disturbances in the equilibrium of the intestinal flora. This plant is also supposed to alleviate intestinal parasites and Candida (according to the observations of many physicians, but other interventions at the same time are needed for optimal effect).

Miscellaneous

In 2000, a research demonstrated that the water extract of Uncaria tomentosa had antioxidant properties. In Argentina, another study also concluded that the water extract of Uncaria tomentosa is an effective antioxidant. The phytochemicals with antioxidant properties found in the Uncaria tomentosa extract are catechins and procyanidins, and also contribute to the anti-inflammatory properties.

Some companies are marketing a formulation made from Uncaria tomentosa and Bixa orellana L. as a healing, anti-inflammatory and diuretic agent. They claim that it is a product with a singular effect over the genitourinary tract and that is specially recommended in promoting prostate health and normal urinary function in men.

In a 2000 Swedish study, Sheng et al. using an aqueous extract treated radiation-induced DNA damage in rats. Results indicated significant repair of DNA breaks.

The oleanolic acid isolated from Uncaria tomentosa has shown anti-allergy actions, but the amounts are so small as to make their presence insignificant in relation to the herbal activity in clinical practice. This substance also shows appreciable antistaphylococcal activity (MIC 8 µg ml^-1) against Staphylococcus aureus.

According to anecdotal information, Uncaria tomentosa facilitates the expulsion of Entamoeba histolytica (a type of detrimental Protozoa) from the body (especially when used in conjunction with Methylsulfonylmethane (MSM)).

Uncaria tomentosa is also considered a nutritional support for people with lupus erythematosus. However, there is one case report of acute renal failure in an adult with systemic lupus erythematosus who took Uncaria tomentosa. Some authorities even advise people with systemic lupus erythematosus not to use Uncaria tomentosa.

In some cases, it is part of adjuvant nutritional therapy for people with Chronic Fatigue Syndrome (CFS): numerous people report relief of symptoms of CFS after using Uncaria tomentosa for at least one month.

This plant is also part of adjuvant nutritional therapy for people with diabetes mellitus.

According to the observations of many physicians, it may alleviate bursitis. Some physicians are also promoting it in order to treat depression.

Uncaria tomentosa also helps to minimize the toxic effects of tobacco smoking. Effectively, this plant significantly reduces the mutagenicity of substances present in the urine of tobacco smokers.

Some indigenous groups only use the water stored in the stem to quench thirst, and as a restorative drink.

Finally, from the stems (not bark) of Uncaria tomentosarattan-like furniture can be woven. In Iquitos, Peru, a demand for this kind of furniture exists.

Phytochemicals:

ajmalicine

akuammigine

alkaloids (at least 17 different ones)

campesterol

catechin

chlorogenic acid

cinchonain

corynantheine

corynoxeine

daucosterol

epicatechin

flavonoids

formaosine-N-oxide

harman

hirsuteine

hirsutine

isomitraphylline

isopteropodine

isorhynchorphylline

loganic acid

lyaloside

mitraphylline

oleanolic acid

palmitoleic acid

pentacyclic oxindole alkaloids

procyanidins

pteropodine

quinovic acid glycosides

rhynchophylline

rutin

sitosterols

speciophylline

sterol fractions

stigmasterol

strictosidines

tannins

triterpenes

uncarine A-F

uncarine F-N-oxide

vaccenic