View source for Uncaria tomentosa

{{Taxobox
| color = lightgreen
| name = ''Uncaria tomentosa''
| image = Thorns U tomentosa.jpg
| image_width = 240px
| image_caption = 
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Magnoliopsida]]
| ordo = [[Gentianales]]
| familia = [[Rubiaceae]]
| subdivision_ranks = Subfamily
| subdivision = Cinchonoideae
| genus = ''[[Uncaria]]''
| species = '''''U. tomentosa'''''
| binomial = ''Uncaria tomentosa''
| binomial_authority = (Willd. ex Schult.) [[A. P. de Candolle|DC.]]
}}

'''''Uncaria tomentosa''''' (popularly known in [[English language|English]] as '''Cat's Claw''', in [[Spanish language|Spanish]] as '''Uña de Gato''' or as indian name '''Vilcacora''') is a woody vine found in the tropical jungles of South and Central America, which derrives its name from its claw-shaped thorns.  It is used as an [[alternative medicine]] in the treatment of a  variety of ailments.

==Biology==
'''''Uncaria tomentosa''''' is a [[liana]] deriving its name from hook-like thorns that resemble the claws of a cat.  ''U. tomentosa'' can grow up to 30m tall, climbing by means of these thorns. The [[leaf|leaves]] are elliptic with a smooth edge, and grow in opposite [[whorl]]s of two.  Cat's claw is indigenous to the [[Amazon rainforest]], with its habitat being restricted primarily to the [[tropics|tropical]] areas of South and Central America. There are two species of Cat's Claw, '''Uncaria tomentosa''' and '''Uncaria guianensis''', each having different properites and uses. The two are frequently confused but  '''U. tomentosa''' is the more heavily researched for medicinal use<ref>Gattuso, M., Di Sapio, O., Gattuso, S. & Li Pereyra, E.  (2004).  Morphoanatomical studies of Uncaria tomentosa and Uncaria guianensis bark and leaves.  ''Phytomedicine, 11,'' 213–223.</ref> and immune modulation, while '''U. guianensis''' may be more useful for osteoarthritis.<ref>Piscoya J, Rodriguez Z, Bustamante SA, et al. Efficacy and safety of freeze-dried cat's claw in osteoarthritis of the knee: mechanisms of action of the species Uncaria guianensis. Inflamm Res. 2001;50:442–448.</ref>  '''U. tomentosa''' is further divided into two [[chemotype]]s with different properties and active compounds, a fact ignored by most manufacturers<ref>Keplinger, K., Laus, G., Wurm, M., Dierich, M.P. & Teppner, Herwig.  (1999).  Uncaria tomentosa (Willd.) DC.—Ethnomedicinal use and new pharmacological, toxicological and botanical results.  ''Journal of Ethnopharmacology, 64,'' 23–34.  Available on-line as a [http://www.samento.com.ec/sciencelib/sarticles/Uncaria81B4.pdf PDF]</ref> that  can have significant implications on both its use as an alternative medicine and in clinical trials to prove or disprove its efficacy.<ref name=varro>[http://www.findarticles.com/p/articles/mi_m0GCU/is_n5_v14/ai_20097503 Nutrition Forum article by Varro E. Tyler on Cat's Claw] (Warning:  pop-ups)</ref>

==Medicinal uses==
The parts used medicinally include the inner bark and root, taken in the form of capsules, tea and extract.

''U. tomentosa'' is used in [[nootropic]] drugs, as well as in treatment of cancer and [[HIV]] infection. It contains several [[alkaloid]]s that are responsible for its overall medical effects, as well as tannins and various phytochemicals.<ref name="Heitzman">Heitzman, M.E., Neto, C.C., Winiarz, E., Vaisberg, A.J. & Hammon, G.B.  (2005).  Ethnobotany, phytochemistry and pharmacology of Uncaria (Rubiaceae).  ''Phytochemistry, 66(1)'', 5-29. PMID 15649507</ref>  The chemotype of the plant determines the dominant type of alkaloid it produces, and thus its properties ''[[in vivo]]''.  One chemotype has roots which produce mostly the pentacyclic alkaloids that are responsible for the immune-strengthening effects desired by most consumers.  The second chemotype produces tetracyclic [[Indole|oxindole]] alkaloids known as rhynchophylline and isorhynchophylline which counteract the immune-strengthening actions of the pentacyclic alkaloids, reduces the [[bradycardia|speed]] and [[blood pressure|force]] of the [[heart]]'s contraction, and in high doses produce [[ataxia]], lack of coordination and [[sedation|sedative]] effects.<ref name=varro/>  Since ''U. tomentosa'' comes in at least these two different chemotypes, without chemical testing it is impossible to know which chemical compounds will predominate in a plant collected randomly from a natural setting.  

Some ingredients appear to act as anti-inflammatory, antioxidant and anticancer agents.<ref name="Heitzman"/>  As a homeopathic treatment, Cat's Claw is used to treat intestinal ailments such as Crohn's disease, gastric ulcers and tumors, parasites, colitis, gastritis, diverticulitis and leaky bowel syndrome, while manufacturers claim that ''U. tomentosa'' can also be used in the treatment of AIDS in combination with AZT, the treatment and prevention of arthritis and rheumatism, diabetes, PMS, chronic fatigue syndrome, prostate conditions,<ref>[http://www.nutrasanus.com/cats-claw.html NutraSanus article on Cat's Claw]</ref> immune modulation,<ref>[http://www.supplementwatch.com/suplib/supplement.asp?DocId=1070 Information on Cat's Claw]</ref> [[Lyme disease]]<ref>[http://www.digitalnaturopath.com/data/cats_claw_controversy.html Treatment of Lyme disease with Cat's Claw]</ref> and [[Lupus erythematosus|systemic lupus erythematosus]].<ref>[http://health.enotes.com/alternative-medicine-encyclopedia/cat-s-claw Cat's claw used to treat Lupus erythematosus]</ref> A 2005 review of the scholarly literature on Cat's Claw indicates there is supporting evidence toward its use in treating cancer, inflammation, viral infection and vascular conditions, and for its use as an immunostimulant, antioxidant, antibacterial and CNS-related agent.<ref name="Heitzman"/> 

===Indigenous use===
The indigenous peoples of South and Central America have used ''U. tomentosa'' for medicinal purposes for two thousand years or more.  Researchers have investigated the use of the plant by the Asháninka tribe of Peru, who use the plant as a general health tonic, [[Birth control|contraceptive]], [[anti-inflammatory]] agent for the gastrointestinal tract, and as a treatment for [[diarrhea]], [[rheumatism|rheumatic disorders]], [[Acne vulgaris|acne]], [[Diabetes mellitus|diabetes]], [[cancer]] and diseases of the [[Urinary system|urinary tract]].<ref>[http://www.longwoodherbal.org/catsclaw/catsclaw.PDF#search=%22Cat's%20Claw%20Ashaninka%20%222000%20years%22%22 The Longwood Herbal Task Force article on Cat's Claw]</ref>

==Allergies==
Individuals [[allergic]] to plants in the [[Rubiaceae]] family and different species of [[Uncaria]] may be more likely to have allergic reactions to Cat's Claw.<ref>[http://www.intelihealth.com/IH/ihtIH/WSIHW000/8513/31402/347002.html?d=dmtContent#dangers Intelihealth article discussing uses and dangers of Cat's Claw]</ref> Reactions can include [[itching]], [[rash]] and allergic [[inflammation]] of the [[kidneys]]. In one documented case, kidney failure occurred in a patient with Lupus erythematosus<ref>Hilepo JN, Bellucci AG, Mossey RT. (1977). Acute renal failure caused by 'cat's claw' herbal remedy in a patient with systemic lupus erythematosus. ''Nephron, 77(3)'' pg. 361.</ref> but it is not known if this was due to an allergic reaction or another cause.

There are other plants which are known as cat's claw (or uña de gato) in Mexico and Latin America; however, they are entirely different plants, belonging to neither the Uncaria genus, nor to the Rubiaceae family. Some of the Mexican uña de gato varieties are known to have toxic properties.

==Footnotes==
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==References==
*[http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?403273 Germplasm Resources Information Network: ''Uncaria tomentosa'']
*[http://www.rain-tree.com/catclaw.htm Rain-tree.com article on Cat's Claw discussing its properties and actions]

==External link==
*[http://www.uncariatomentosa.com/abstracts.php Webpage on Cat's Claw with a library of scientific abstracts organized by year]

[[Category:Rubiaceae]]
[[Category:Flora of Central America]] 
[[Category:Flora of South America]] 
[[Category:Alternative medicine]]
[[Category:Medicinal plants]]