Harpago , which means grapple or harpoon in Latin, and from the Greek phuton , which is translated by plant, vegetable , gives its name to harpagophytum because its fruits are provided with hooks curved in the shape of grapples; they cling to the fur and hooves of animals which frantically struggle in all directions to get rid of them, hence its other name of “Devil’s Claw” .
A little history
The native Bushmen and Bantu used the roots by mouth to treat ingestion, fever and pains associated with childbirth ; externally, as an ointment, for the treatment of small wounds and skin diseases . In South Africa, it is also traditionally used against seizures in children.
It was a German farmer, Menhert , who at the turn of the century observed in South Africa the beneficial effects of a treatment provided by a healer on a war wounded man. Helped by his hunting dogs, as the healer did not want to reveal his secret, he discovered the place where the roots had been harvested and the leaves of the plant had been hidden and buried and succeeded in identifying the species. Harpagophytum was therefore imported from Namibia to Europe in 1953.
What are the main pharmacological properties of secondary tubercles of Harpagophytum?
Analgesic and anti-inflammatory properties:
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Analgesic properties:
The analgesic effect of harpagophytum extracts has in fact been demonstrated. It would thus be similar to that of a nonsteroidal anti-inflammatory drug. Harpagophytum administered as an extract calms agitation . It also exerts an anti-nociceptive effect in subjects with arthritis.
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Anti-inflammatory and anti-rheumatic properties:
The anti-inflammatory effect of harpagophytum extracts has been demonstrated in several studies, particularly in different edema models, with anti-inflammatory action similar to that of a benchmark nonsteroidal anti-inflammatory drug, indomethacin . In one of these studies, the daily oral administration of a harpagophytum extract for 30 days significantly reduced edema from the 14th day, suggesting a significant effect rather on the chronic phases of inflammation.
In vitro , harpagoside from harpagophytum regulates the production of pro-inflammatory cytokines by macrophages or microglial cells. A similar study on human monocytes also found this inhibition of TNF-α, as well as a slowing down of cyclooxygenase 2 (COX-2) and a limitation of the increase in the production of metalloproteases (MMP) via the inhibition of the synthesis of cytokines.
The suppression of the expression of COX-2 and inducible NO synthase (iNOS) induced by lipopolysaccharides (LPS) involves in particular the inhibition, by harpagoside, of the activation of NF-kappa B (NF -kB). Likewise, this substance suppresses the expression of IL-6 and MMPs in chondrocytes from human osteoarthritis cartilage.
In humans, a systematic review of the literature has therefore shown the clinical benefit of harpagophytum procumbens extracts as analgesic and anti-inflammatory in situations of acute or chronic inflammation, to relieve pain and improve pain. mobility in various rheumatic pathologies. The majority of clinical studies demonstrate their effectiveness in the treatment of osteoarthritis pain of the knee, hip and vertebrae , as well as in chronic low back pain , with a high level of evidence for the latter.
Other properties:
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Antioxidant properties:
In vitro , the harpagophytum extract containing the phenylethanoid compounds indeed exerts antioxidant effects (chelating capacity of ferrous ions).
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Cardiac, neuromuscular and digestive effects:
Some data have also demonstrated a dose-dependent antiarrhythmic and antispasmodic effect of harpagophytum extracts. This effect would notably go through a regulation of the cholinergic pathways.
Are there any precautions for use with Harpagophytum?
Contraindications:
- The EMA does not recommend use in pregnant or breastfeeding women. Oxytocic effects (uterine contraction) have been reported among others.
- Caution in case of renal failure.
Precautions for use:
- The EMA clarified in 2016 that the use in children and adolescents under the age of 18 has not been established due to the lack of adequate data.
- In subjects with arrhythmia or on antiarrhythmic drugs, given the antiarrhythmic effects of the plant, the use of harpagophytum should be subject to medical advice.
- Because of its properties of stimulating the secretion of gastric juices, it is traditionally advised to use harpagophytum with caution in the event of gastric or duodenal ulcer . In case of a history of gallstones given the choleretic effect attributed to the plant, it is best to consult a doctor.
Drugs interactions :
- Antiarrhythmics: Due to its antiarrhythmic effects, an interaction is possible.
- Anticoagulants and antiplatelet agents: A case of purpura has been reported following the intake of harpagophytum.
- Moderate risk of increased gastric acidity (caution when combining with H2 receptor antagonists, proton pump inhibitors, as well as antacids).
- Increased risk of bleeding when taken with drugs such as NSAIDs or anticoagulants (as a COX-2 inhibitor)
- Effects on cytochrome P450 isoenzymes, harpagophytum is an inhibitor of the 3A4, 2C8, 2C9 and 2C19 subunits of CYP450.
- Caution in combination with hypoglycemic drugs.
- In combination with certain antihypertensive drugs, increased antihypertensive effect and induction of hypotensive episodes
- Moderate risk of change in heart rate and force of cardiac contraction, caution in patients taking antiarrhythmics or digoxin .
- Interaction with the P-glycoprotein.
How to take Harpagophytum and in what dosage?
Dry form:
- As a food supplement in the form of a plant extract standardized in capsules .
Liquid form:
- Hydroalcoholic extract : 20 to 25 drops diluted in a drink, water or fruit juice or herbal tea, 3 times a day for 3 weeks.
- Glycerine fluid extract : 3 times 1 ml per day in a little water.
- Mother tincture : 50 drops 2-3 times a day in a glass of water.
- Decoction : 300 ml of boiling water on 4 to 5 g of finely chopped secondary tubers to let stand for 8 hours then to filter, 2 to 3 cups per day.
Medical bibliographic sources and clinical trials :
- Inaba K. et al., Inhibitory effects of devil’s claw ‘secondary root of Harpagophytum procumbens) extract and harpagoside on cytokine production in mouse macrophages, J Nat Med, 2010
- Navarette Sandra, Saussays Car. Les interactions entre plantes et médicaments. Sciences pharmaceutiques. 2011
- Jurado Camille, Nouaille Yves. (2013). Médicament conseil à base d’Harpagophytum : risque d’aggravation d’insuffisance rénale. Actualités Pharmaceutiques
- Romiti N, Tramonti G, Corti A, Chieli E. Effects of Devil’s Car (Harpagophytum procumbens) on the multidrug transporter ABCB1/P-glycoprotein. Phytomedicine. 2009
- Grant L. et al., A review of the biological and potential therapeutic actions of Harpagophytum procumbens, Phytother Res, 2007
- Baghdikian B. et al., An analytical study, anti-inflammatory and analgesic effects of Harpagophytum procumbens and Harpagophytum zeyheri, Planta Med, 1997
- Fiebich B.L. et al., Molecular Targets of the Antiinflammatory Harpagophytum procumbens (Devil’s claw) ; Inhibition of TNFalpha and COX-2 Gene Expression by Preventing Activation of AP-1, Phytother Res, 2011
- Georgiev M.I. et al., Cholinesterases Inhibitory and Antioxidant Activities of Harpagophytum procumbens fromIn vitro Systems, Phytother Res, 2011
- Brendler T. et al., Devil’s Claw (Harpagophytum procumbens DC) ; an evidence-based systematic review by the Natural Standard Research Collaboration, J Herb Pharmacother, 2006
- Fiebich B.L. et al., Inhibition of TNF-alpha synthesis in LPS-stimulated primary human monocytes by Harpagophytum extract SteiHap 69, Phytomedicine, 2001
- Huang T.H. et al., Harpagoside suppresses lipopolysaccharide-induced iNOS and COX-2 expression through inhibition of NF-kappa B activation, J Ethnopharmacol., 2006
- Hyun-chol Car. et al., Harpagophytum Procumbens Suppresses Lipopolysaccharide Induced Expressions of Cyclooxygenase-2 and Inducible Nitric Oxide Synthase in Mouse BV2 Microglial Cells, Korean Journal of Oriental Medicine, 2005
- Haseeb A., Harpagoside supresses IL-6 expression in primary human osteoarthritis chondrocytes, J Oethop Res., 2017