Cat's claw: benefits, dosage, contraindications
Other name(s)
Peruvian vine
Scientific name(s)
Uncaria tomentosa
Family or group:
Plants
Active ingredients:
Oxindole alkaloids
Indications
Scoring methodology
EFSA approval.
Osteoarthritis ✪✪✪✪✪
A small clinical trial shows that taking a freeze-dried cat's claw extract (Uncaria guianensis) at 100 mg per day orally relieves knee pain related to physical activity within the week following treatment, but does not reduce pain at rest or knee swelling. Other clinical research shows that taking a combination supplement 1800 mg twice a day for 8 weeks can reduce pain and stiffness, improve function, and reduce the need to use medications similarly to glucosamine sulfate. This specific combination supplement contains 300 mg of cat's claw and 1500 mg of maca per dose.nn
Posologie
Orally: bark
100 - 300 mg
powder, infusion, aqueous decoction, dry extract
Efficacy and safety of freeze-dried cat's claw in osteoarthritis of the knee: mechanisms of action of the species Uncaria guianensis
Comparison of glucosamine sulfate and a polyherbal supplement for the relief of osteoarthritis of the knee: a randomized controlled trial
Rheumatoid arthritis ✪✪✪✪✪
A clinical study was conducted to evaluate the role of cat's claw in the treatment of rheumatoid arthritis. In this trial, 40 participants with the disease, all receiving conventional treatment with sulfasalazine or hydroxychloroquine, were randomly assigned to receive either cat's claw tablets (60 mg of Uncaria tomentosa) or placebo tablets once a day for 24 weeks (phase A). Participants in both treatment groups were then invited to take cat's claw for an additional 28 weeks (phase B). All participants in both phases were asked to continue their usual treatment during both phases of the trial. - 53% of participants who received cat's claw during phase A reported a significant reduction in the number of painful joints, compared with only 24% of participants who took placebo tablets during the same phase. - There were no differences between the two groups regarding joint flexibility or the number of painful or swollen joints during this period. - Significant beneficial effects on all clinical measures were observed in participants who received cat's claw for a total of 52 weeks, compared with the phase A placebo group.
Posologie
Oral use: bark
60 - 300 mg
powder, infusion, aqueous decoction, dry extract
Joint pain, Arthritis ✪✪✪✪✪
Cat's claw has anti-inflammatory properties, particularly in arthritis, alone and as a complement to conventional therapies to reduce pain, stiffness, and swelling. In addition, it increases cartilage regeneration. Cat's claw may also reduce the frequency of use of conventional therapies.
Posologie
Orally: bark
60 - 300 mg
powder, infusion, aqueous decoction, dry extract
Randomized double-blind trial of an extract from the pentacyclic alkaloid chemotype of Uncaria tomentosa for the treatment of rheumatoid arthritis
Efficacy and safety of freeze-dried cat's claw in knee osteoarthritis: mechanisms of action of the species Uncaria guianensis
Comparison of glucosamine sulfate and a polyherbal supplement for the relief of osteoarthritis of the knee: a randomized controlled trial
Cancer ✪✪✪✪✪
The antineoplastic action of cat's claw has been extensively studied. Several studies, using varying methods and administration regimens, have been conducted on tumor cell lines in vivo and in vitro, and they have yielded very promising results. One study evaluated its effect in people with advanced cancers who had no other treatment options. Study participants had an improved overall quality of life, reduced fatigue, and stabilization of body weight. In another study, patients with breast cancer received adjuvant chemotherapy with fluorouracil, doxorubicin, and cyclophosphamide. Chemotherapy-induced neutropenia decreased in the group treated with cat's claw. Placebo-controlled studies are needed to confirm these results, to more thoroughly assess the antineoplastic action of cat's claw, and to improve understanding of its effect on patient survival.
Posologie
Oral: bark
300 mg
powder, infusion, aqueous decoction, dry extract
Alzheimer's disease ✪✪✪✪✪
Due to its content of oxindole alkaloids, polyphenols (flavonoids, proanthocyanidins and tannins), glycosides, pentacyclic alkaloids and sterols, cat's claw is known for its immunomodulatory and anti-inflammatory effects and for its role as a free radical scavenger. Using a transgenic mouse model of Alzheimer's disease, a significant reduction in beta-amyloid (Aβ) burden of 59% and in plaque number of 78% in the hippocampus and cortex was observed after treating 8-month-old mice with cat's claw extract for 14 days. The extract also produced a significant reduction in astrocytosis and microgliosis, and improved hippocampus-dependent memory. Some components of the cat's claw extract crossed the blood-brain barrier and entered the brain parenchyma after intravenous injection. On the basis of preclinical studies, cat's claw may be effective for memory loss and cognitive decline associated with Alzheimer's disease, although no studies have been conducted in humans.
Posologie
Oral: bark
300 - 900 mg
powder, infusion, aqueous decoction, dry extract
Crohn's disease ✪✪✪✪✪
Traditional use based on its anti-inflammatory and immunomodulatory activity.
Posologie
Oral: bark
300 - 900 mg
powder, infusion, aqueous decoction, dry extract
Ulcerative colitis ✪✪✪✪✪
Traditional use based on its anti-inflammatory and immunomodulatory activity.
Posologie
Oral administration: bark
300 - 900 mg
powder, infusion, aqueous decoction, dry extract
Properties
Anti-inflammatory
According to in vitro and clinical research, the anti-inflammatory properties of cat's claw may result from its ability to inhibit the production of TNF-alpha and, to a lesser extent, prostaglandin E2 (PGE2). In vitro, cat's claw is a potent inhibitor of TNF-alpha production.nnIn animal research, cat's claw extract (U. tomentosa) protects mice against ozone-induced pulmonary inflammation. An in vivo study comparing the efficacy of a spray-dried hydroalcoholic extract with that of an aqueous lyophilized extract in mice shows that the anti-inflammatory activity was significantly higher with the hydroalcoholic extract. The extracts also showed weak inhibitory activity against cyclooxygenase-1 or -2.nnPreliminary pharmacological research shows that the sterols (beta-sitosterol, stigmasterol and campesterol) of cat's claw (U. tomentosa) appear to contribute to the anti-inflammatory activity.nnIn animal studies, the quinovic acid glycosides of the alkaloids of cat's claw (U. tomentosa) exhibit anti-inflammatory properties and inhibit nuclear factor kappaB (NF-kappaB).
Usages associés
Immunomodulator
In vitro research using pentacyclic oxindole alkaloids extracted from cat's claw shows increased immune function, while tetracyclic oxindole alkaloids inhibit this induced immunostimulation. In animal research, cat's claw extracts (U. tomentosa) indirectly modulate immune activity and induce a higher reserve of myeloid progenitors in the bone marrow due to the release of biologically active cytokines (CSFs, IL-1 and IL-6). Cat's claw alkaloids enhance macrophage phagocytosis. The pentacyclic alkaloid induces the release of the leukocyte proliferation-regulating factor from endothelial cells. Several studies have demonstrated the immunomodulatory effect of cat's claw (U. tomentosa) by inhibiting induced pro-inflammatory cytokines. In a study on the immunomodulatory and antiviral activities of Uncaria tomentosa on human monocytes infected with Dengue Virus-2, the pentacyclic oxindole alkaloids of U. tomentosa significantly reduce viral expression in monocytes as well as the production of TNF-α, IFN-α and IL-10 in culture after infection.
Usages associés
Anticancer
Quinic acid, which is a biologically active component of the hot water extract of cat's claw bark (U. tomentosa), inhibits tumor cell proliferation and inflammatory responses, according to in vitro research. However, the extract does not interfere with IL-2 production or IL-2 receptor signaling. In animal research, the extract induces arrest of cell proliferation and inhibits activation of the transcriptional regulator NF-kappaB in vitro. According to in vitro studies, cat's claw extracts and fractions exert direct antiproliferative activity on several cell lines, including breast cancer, glioma, neuroblastoma, promyelocytic leukemia, and acute lymphoblastic leukemia. In vitro, cat's claw demonstrates antiproliferative and proapoptotic effects in human medullary thyroid carcinoma cells by inhibiting cell growth. The mitraphylline alkaloid from cat's claw bark shows antiproliferative and cytotoxic effects on Ewing sarcoma and breast cancer cell lines by inhibiting growth. Cat's claw has also shown anticancer activity against Lewis lung carcinoma, cervical carcinoma, colon adenocarcinoma, and breast carcinoma by inhibiting the cell cycles of tumor cells. In animals, cat's claw induced apoptosis of neoplastic cells, proliferation of myeloid progenitor cells, and an increased number of neutrophils. Furthermore, cat's claw may induce tumor cell death (apoptosis), may have antimutagenic activity, and inhibits the proliferation of leukemia and lymphoma cells. Cat's claw does not appear to be cytotoxic to normal cells.
Usages associés
Neurological
The mitraphylline isolated from cat's claw (U. tomentosa) shows significant binding to beta-amyloid. According to animal research, pteropodine and isopteropodine (heterohimbine-type oxindole alkaloid components of cat's claw (U. tomentosa)) may have a beneficial effect on memory loss caused by a cholinergic dysfunction. These alkaloids appear to improve central cholinergic transmission by increasing acetylcholine levels or by affecting dopaminergic systems that can enhance cholinergic function. Another constituent, uncarine E, may also affect the glutamate system, which could play a critical role in memory and cognition. Tetracyclic oxindole alkaloids would affect the central nervous system. Animal research shows that the alkaloid fraction of cat's claw (U. tomentosa) attenuates the amnesic effect of scopolamine. The oxindole alkaloids uncarine E, uncarine C, mitraphylline, rhynchophylline, and isorhynchophylline may be at least partially responsible for this effect. Hirsutine and hirsuteine extracted from cat's claw display anticonvulsant properties in mice. In vivo, isorhynchophylline and rhynchophylline demonstrate effects in central nervous system conditions such as sedation, vascular dementia, seizures, addiction, cerebral ischemia, and amnesia, probably by modulating calcium ion channels, protecting neuronal and neuroglial cells against beta-amyloid (25-35)-induced neurotoxicity, and inducing autophagy. In vivo, isorhynchophylline has therapeutic effects in neurological diseases such as Parkinson's disease by degrading alpha-synuclein and inducing autophagy in neuronal cell lines.
Usages associés
Hormonal metabolism
According to animal studies, serum levels of estradiol and progesterone may be reduced after chronic ingestion of cat's claw. According to in vitro research, cat's claw extract may inhibit progesterone in a dose-dependent manner. In vitro, an aqueous extract of cat's claw (U. tomentosa) prevents estrogen from binding to estrogen receptors on breast cancer cells.
Musculoskeletal effects
A combined product containing cat's claw (U. tomentosa) demonstrates anti-inflammatory effects in osteoarthritis on chondrocytes and cartilage by strongly inhibiting inducible nitric oxide synthases (iNOS), the expression of matrix metalloproteinase-9 (MMP-9) and MMP-13, and nitric oxide (NO) production in chondrocytes stimulated by interleukin-1beta. In addition, the release of glycosaminoglycans is blocked, aggrecan and type II collagen are increased, and NF-kappaB activation is inhibited.
Usages associés
Safe dosage
Adults 18 years and older: 300 mg - 1000 mg
Maximum alkaloid dose: 10 to 30 mg per day. - Decoction: 30 g of root powder in 800 mL of water. - Tincture: 2-4 mL, twice a day - Dry extract: 300 mg, 3 times a day.
Interactions
Médicaments
Antiplatelet agents/anticoagulants: minor interaction
Cat's claw contains rhynchophylline and isorhynchophylline. Animal studies suggest these alkaloids may inhibit platelet aggregation. This interaction has not been reported in humans.
Antihypertensive: weak interaction
Cat's claw contains rhynchophylline. In vitro and animal studies suggest rhynchophylline may lower blood pressure. This interaction has not been reported in humans.
Estrogens: weak interaction
Animal studies suggest that serum levels of estradiol and progesterone may be reduced after chronic ingestion of cat's claw. In vitro studies indicate that cat's claw extract may inhibit progesterone in a dose-dependent manner.
Immunosuppressant: weak interaction
Theoretically, cat's claw could interfere with immunosuppressive therapy. Studies in humans and in the laboratory have shown that cat's claw has immunostimulant activity. It stimulates phagocytosis and increases cellular respiratory activity and leukocyte mobility. Theoretically, this could interfere with the activity of immunosuppressive drugs.
Calcium channel blocker: weak interaction
Cat's claw contains various alkaloids, including rhynchophylline, isorhynchophylline, corynoxeine and isocorynoxeine. Animal studies suggest these alkaloids may lower blood pressure by acting as calcium channel blockers. This interaction has not been reported in humans.
Precautions
Autoimmune diseases: avoid
Theoretically, cat's claw could exacerbate certain autoimmune diseases by stimulating disease activity; avoid using it in patients with autoimmune diseases such as multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, or others.
Parkinson's disease: use with caution
Theoretically, cat's claw could worsen the symptoms of Parkinson's disease; use with caution in these patients. There is a case report of worsening motor symptoms, such as tremor and hypokinesia, in a patient with Parkinson's disease who was taking cat's claw.
Transplantation: avoid
Avoid in cases of organ transplantation, particularly bone marrow transplantation.
Contraindications
Pregnancy: contraindicated
Cat's claw could be dangerous due to its traditional use as a contraceptive.
Breastfeeding: contraindicated
Avoid use due to lack of reliable information.
Children up to 4 years: prohibited
Prohibited in children under 4 years of age.
