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Cats Claw (Uncaria tomentosa)

Uncaria tomentosa, known as cats’ claw after its curved, claw-like thorns that grow on its stem, is a vine that can climb as high as 100 feet. It grows mostly in the Amazon rainforest up to 100 feet high, as well as other tropical areas in South and Central America. Much of the cat's claw sold in the United States was grown in Peru. Cat’s claw includes two species, Uncaria tomentosa and Uncaria guinaensis and the extract is usually made from their root bark most commonly from U. tomentosa.

Cats Claw (Uncaria tomentosa)

Uses

The bark and root have been used by South Americans for centuries to treat health problems including arthritis, stomach ulcers, inflammation, dysentery, and fevers. It is marketed as an herbal remedy to treat viral infections, intestinal bacterial overgrowth, parasites, diverticulitis, peptic ulcers, colitis, gastritis, hemorrhoids, arthritis, and certain cancers.

Chemistry/Pharmacology

Constituents of cat’s claw extracts include proanthocyanidins [proanthocyanidin B2 (the main component), proanthocyanidin B4, proanthocyanidin C1, an epicatechin trimer, epiafzelechin-4β→8-epicatechin, and an epicatechin tetramer, oxindole alkaloids (isopteropodine, pteropodine, rhynchophylline, mytraphylline, speciophylline, uncarine F and uncarine E), indole alkaloidal glucosides (cadambine, 3-dihydrocadambine and 3-isodihydrocadambine), quinovic acid glycosides, tannins, polyphenols, catechins, beta sitosterol, and proteins which individually or synergistically contribute to their therapeutic properties.

Clinical Studies

Preliminary clinical findings suggest that cat’s claw may benefit patients with active rheumatoid arthritis, and be useful for the treatment of denture stomatitis. Cat’s claw also was shown to exert anticancer effects against several cancer cell lines, and anti-neoplastic effects in a breast tumor model. It was also reported to stimulate healthy hematopoietic tissue cells and reduce side effects, such as neutropenia, associated with chemotherapy. These observations were reported in cancer patients as well. In a study of breast cancer patients, cat’s claw reduced adverse effects due to chemotherapy and improved the quality of life in patients with advanced cancer.

Biomechanical Mechanism

In vitro studies show that constituents of this plant enhance phagocytosis, display immunomodulatory properties, alleviate inflammation, and possess antiviral and antimutagenic activities. A cat’s claw extract was also shown to modulate DNA repair in human skin. The oxindole alkaloids have immunostimulating properties in vitro, increasing phagocytotic activity and synthesis of WBCs and enhancing T-helper cell function. Inhibition of TNF-alpha production has been linked to observed anti-inflammatory activities. Mitraphylline isolated from cat’s claw was also identified as possessing anti-inflammatory effects by inhibiting the release of interleukins 1α, 1β, 4, 17, and TNF-α.

In other studies, aqueous extracts of cat’s claw were shown to enhance DNA repair after chemical-induced damage. Protection against oxidative DNA damage following UVB exposure may occur via enhanced base excision repair and inherent antioxidant effects. The biphasic way cat’s claw modulates anxiety, initially inducing and then reversing the effect after long-term administration, is attributed to the presence of alkaloids and flavonols.

The quinovic acid glycoside purified fraction of cat’s claw was shown to inhibit the growth of human bladder cancer cell lines by inducing apoptosis through modulation of NF-κB. Cat’s claw also inhibited lactate dehydrogenase-A, an enzyme that is highly expressed in malignant and treatment-resistant tumors with poor clinical outcomes. In vivo studies demonstrated antineoplastic effects against breast tumors due to modulation of oxidative stress and synergy among constituents with antioxidant properties, rather than alkaloid activity.

Sources/Articles

Aquino, R., De Simone, F., Vincieri, F. F., Pizza, C., & Gaćs-Baitz, E. (1990). New polyhydroxylated triterpenes from Uncaria tomentosa. Journal of Natural Products, 53(3), 559–564. 10.1021/np50069a004 https://pubs.acs.org/doi/pdf/10.1021/np50069a004

Aquino, R., De Tommasi, N., De Simone, F., & Pizza, C. (1997). Triterpenes and quinovic acid glycosides from Uncaria tomentosa. Phytochemistry, 45(5), 1035–1040. 10.1016/S0031-9422(96)00716-9
https://www.sciencedirect.com/science/article/abs/pii/S0031942296007169

Batiha, G. E.-S., Magdy Beshbishy, A., Wasef, L., Elewa, Y. H. A., Abd El-Hack, M. E., Taha, A. E., Al-Sagheer, A. A., Devkota, H. P., & Tufarelli, V. (2020). Uncaria tomentosa (Willd. ex Schult.) DC.: A review on chemical constituents and biological activities. Applied Sciences, 10(8), 2668. 10.3390/app10082668 https://www.mdpi.com/2076-3417/10/8/2668

Bigliani MC, Rosso MC, Zunino PM, et al. Anxiogenic-like effects of Uncaria tomentosa (Willd.) DC. aqueous extract in an elevated plus maze test in mice: a preliminary study. Nat Prod Res. 2013;27(18):1682-1685.

Caon T, Kaiser S, Feltrin C, et al. Antimutagenic and antiherpetic activities of different preparations from Uncaria tomentosa (cat’s claw). Food Chem Toxicol. Apr 2014;66:30-35.

de Paula LC, Fonseca F, Perazzo F, et al. Uncaria tomentosa (cat’s claw) improves quality of life in patients with advanced solid tumors.J Altern Complement Med. 2015 Jan;21(1):22-30.

Dietrich F, Kaiser S, Rockenbach L, et al. Quinovic acid glycosides purified fraction from Uncaria tomentosa induces cell death by apoptosis in the T24 human bladder cancer cell line. Food Chem Toxicol. May 2014;67:222-229.

Dreifuss AA, Bastos-Pereira AL, Fabossi IA, et al. Uncaria tomentosa exerts extensive anti-neoplastic effects against the Walker-256 tumour by modulating oxidative stress and not by alkaloid activity. PLoS One. 2013;8(2):e54618.

Erowele GI, Kalejaiye AO. Pharmacology and therapeutic uses of cat’s claw. Am J Health Syst Pharm. Jun 1 2009;66(11):992-995.

Farias I, do Carmo Araujo M, Zimmermann ES, et al. Uncaria tomentosa stimulates the proliferation of myeloid progenitor cells. J Ethnopharmacol. Sep 1 2011;137(1):856-863.

Garcia Gimenez D, Garcia Prado E, Saenz Rodriguez T, et al. Cytotoxic effect of the pentacyclic oxindole alkaloid mitraphylline isolated from Uncaria tomentosa bark on human Ewing’s sarcoma and breast cancer cell lines. Planta Med. Feb 2010;76(2):133-136.

Garcia Prado E, Garcia Gimenez MD, De la Puerta Vazquez R, et al. Antiproliferative effects of mitraphylline, a pentacyclic oxindole alkaloid of Uncaria tomentosa on human glioma and neuroblastoma cell lines. Phytomedicine. Apr 2007;14(4):280-284.

Hemingway SR, Phillipson JD. Proceedings: Alkaloids from S. American species of Uncaria (Rubiaceae). J Pharm Pharmacol. Dec 1974;26 Suppl:113P.

Kaiser S, Dietrich F, de Resende PE, et al. Cat’s claw oxindole alkaloid isomerization induced by cell incubation and cytotoxic activity against T24 and RT4 human bladder cancer cell lines. Planta Med. Oct 2013;79(15):1413-1420.

Kitajima, M., Hashimoto, K. I., Yokoya, M., Takayama, H., & Aimi, N. (2000). Two new 19-hydroxyursolic acid-type triterpenes from Peruvian “Una de Gato” (Uncaria tomentosa). Tetrahedron, 56(4), 547–552. 10.1016/S0040-4020(99)01048-0 10.1016/S0040-4020(99)01048-0 https://www.sciencedirect.com/science/article/abs/pii/S0040402099010480

Laus, G., Brössner, D., & Keplinger, K. (1997). Alkaloids of peruvian Uncaria tomentosa. Phytochemistry, 45(4), 855–860. 10.1016/S0031-9422(97)00061-7 10.1016/S0031-9422(97)00061-7 https://www.sciencedirect.com/science/article/abs/pii/S0031942297000617

Lima-Junior, R. S., Da Silva Mello, C., Kubelka, C. F., Siani, A. C., & Valente, L. M. M. (2013). Uncaria tomentosa alkaloidal fraction reduces aracellular permeability, il-8 and ns1 production on human microvascular endothelial cells infected with dengue virus. Natural Product Communications, 8(11), 1547–50.
https://journals.sagepub.com/doi/pdf/10.1177/1934578X1300801112

Mammone T, Akesson C, Gan D, et al. A water soluble extract from Uncaria tomentosa (Cat’s Claw) is a potent enhancer of DNA repair in primary organ cultures of human skin. Phytother Res. Mar 2006;20(3):178-183.

Montoro, P., Carbone, V., de Dioz Zuniga Quiroz, J., De Simone, F., & Pizza, C. (2004). Identification and quantification of components in extracts of Uncaria tomentosa by HPLC-ES/MS. Phytochemical Analysis, 15(1), 55–64. 10.1002/pca.740

Mur E, Hartig F, Eibl G, et al. Randomized double blind trial of an extract from the pentacyclic alkaloid-chemotype of Uncaria tomentosa for the treatment of rheumatoid arthritis. J Rheumatol. Apr 2002;29(4):678-681. https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/abs/10.1002/pca.740

Navarro, M., Arnaez, E., Moreira, I., Hurtado, A., Monge, D., & Monagas, M. (2019). Polyphenolic composition and antioxidant activity of Uncaria tomentosa commercial bark products. Antioxidants, 8(9), 339. 10.3390/antiox8090339 https://www.mdpi.com/2076-3921/8/9/339

Navarro-Hoyos, M., Lebrón-Aguilar, R., Quintanilla-López, J., Cueva, C., Hevia, D., Quesada, S., Azofeifa, G., Moreno-Arribas, M., Monagas, M., & Bartolomé, B. (2017). Proanthocyanidin characterization and bioactivity of extracts from different parts of Uncaria tomentosa L. (cat’s claw. Antioxidants, 6(1), 12. 10.3390/antiox6010012 https://www.mdpi.com/2076-3921/6/1/12

Ostrakhovich, E. A., Mikhal'chik, E. V., Getmanskaya, N. V., & Durnev, A. D. (1997). Antioxidant activity of the extract from Uncaria Tomentosa. Pharmaceutical Chemistry Journal, 31(6), 326–329. 10.1007/BF02464127 https://link.springer.com/article/10.1007/BF02464127

Peñaloza, E. M. C., Kaiser, S., De Resende, P. E., Pittol, V., Carvalho, . R., & Ortega, G. G. (2015). Chemical composition variability in the Uncaria tomentosa (cat’s claw) wild population. Quimica Nova, 38(3), 378–386. 10.5935/0100-4042.20150007. https://www.scielo.br/j/qn/a/zccdwKZQcWRG9VPQNfG3KvB/abstract/?lang=en

Pilarski R, Poczekaj-Kostrzewska M, Ciesiolka D, et al. Antiproliferative activity of various Uncaria tomentosa preparations on HL-60 promyelocytic leukemia cells. Pharmacol Rep. Sep-Oct 2007;59(5):565-572.

Reis SR, Valente LM, Sampaio AL, et al. Immunomodulating and antiviral activities of Uncaria tomentosa on human monocytes infected with Dengue Virus-2. Int Immunopharmacol. Mar 2008;8(3):468-476.

Rinner B, Li ZX, Haas H, et al. Antiproliferative and pro-apoptotic effects of Uncaria tomentosa in human medullary thyroid carcinoma cells. Anticancer Res. Nov 2009;29(11):4519-4528.

Riva L, Coradini D, Di Fronzo G, et al. The antiproliferative effects of Uncaria tomentosa extracts and fractions on the growth of breast cancer cell line. Anticancer Res. Jul-Aug 2001;21(4A):2457-2461.

Rojas-Duran R, Gonzalez-Aspajo G, Ruiz-Martel C, et al. Anti-inflammatory activity of Mitraphylline isolated from Uncaria tomentosa bark. J Ethnopharmacol. Oct 11 2012;143(3):801-804.

Sandoval M, Charbonnet RM, Okuhama NN, et al. Cat’s claw inhibits TNFalpha production and scavenges free radicals: role in cytoprotection. Free Radic Biol Med. Jul 1 2000;29(1):71-78.

Sandoval M, Okuhama NN, Zhang XJ, et al. Anti-inflammatory and antioxidant activities of cat’s claw (Uncaria tomentosa and Uncaria guianensis) are independent of their alkaloid content. Phytomedicine. May 2002;9(4):325-337.

Santos Araujo Mdo C, Farias IL, Gutierres J, et al. Uncaria tomentosa-adjuvant treatment for breast cancer: clinical trial. Evid Based Complement Alternat Med. 2012;2012:676984.

Sheng Y, Bryngelsson C, Pero RW. Enhanced DNA repair, immune function and reduced toxicity of C-MED-100, a novel aqueous extract from Uncaria tomentosa. J Ethnopharmacol. Feb 2000;69(2):115-126.

Sheng Y, Li L, Holmgren K, et al. DNA repair enhancement of aqueous extracts of Uncaria tomentosa in a human volunteer study. Phytomedicine. Jul 2001;8(4):275-282.

Snow, A. D., Castillo, G. M., Nguyen, B. P., Choi, P. Y., Cummings, J. A., Cam, J., Hu, Q., Lake, T., Pan, W., Kastin, A. J., Kirschner, D. A., Wood, S. G., Rockenstein, E., Masliah, E., Lorimer, S., Tanzi, R. E., & Larsen, L. (2019). The Amazon rain forest plant Uncaria tomentosa (cat’s claw) and its specific proanthocyanidin constituents are potent inhibitors and reducers of both brain plaques and tangles. Scientific Reports, 9(1), 561. 10.1038/s41598-019-38645-0 https://www.nature.com/articles/s41598-019-38645-0?crsi=undefined&cicada_org_src=healthwebmagazine.com&cicada_org_mdm=direct

Styczynski J, Wysocki M. Alternative medicine remedies might stimulate viability of leukemic cells. Pediatr Blood Cancer. Jan 2006;46(1):94-98.

Weiss J. Herb⁻Drug Interaction Potential of Anti-Borreliae Effective Extracts from Uncaria tomentosa (Samento) and Otoba parvifolia (Banderol) Assessed In Vitro. Molecules. 2018 Dec 31;24(1). pii: E137.

Yepes-Pérez, Andres F., Oscar Herrera-Calderon, and Jorge Quintero-Saumeth. "Uncaria tomentosa (cat’s claw): a promising herbal medicine against SARS-CoV-2/ACE-2 junction and SARS-CoV-2 spike protein based on molecular modeling." Journal of Biomolecular Structure and Dynamics (2020): 1-17. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7657399/


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