Background: Osteoarthritis (OA) is a degenerative disease of the joint occurring in elderly population. According to World Health Organization, its worldwide prevalence ranges from 11,8% to 12,7%. Since it is known that OA has an inflammatory cause, with IL-1β and TNF-α being the key cytokines that drive the production of inflammatory mediators and matrix-degrading enzymes, the compounds with anti-inflammatory properties are targeted as therapeutic options for osteoarthritis treatment. Curcumin is a plant-derived compound extracted from the rhizomes of turmeric (Curcuma longa). It has been demonstrated as an effective anti-inflammatory and antioxidative agent. In vitro studies have shown that curcumin can block the activation of NF-κB system in the chondrocytes. Therefore, it prevents the apoptosis of chondrocytes, suppress the release of proteoglycans and metal metalloproteases and expression of cyclooxygenase, prostaglandin E-2, and inflammatory cytokines in chondrocytes. Besides its influence on inflammatory markers, clinical trials also demonstrated curcumin’s effects in pain and function in patients with osteoarthritis.

Objectives: The purpose of this paper is to critically review evidences regarding the role of curcumin in osteoarthritis treatment.

Methods: PubMed/MEDLINE, Lilacs, and SCIELO databases were searched using the terms “curcumin” aND “osteoarthritis” without imposing time limitations. The search was limited to humans and to the English and Portuguese languages. Studies that met the following inclusion criteria were included in the review: 1) clinical trials that evaluated the effects of curcumin on osteoarthritis. The selection phase involved a review of abstracts and an examination of the full text based on the eligibility criteria and the last search was conducted on January 2019.

Results: Overall, 9 clinical trials involving a total of 797 patients met the inclusion criteria. The studies have a degree of heterogeneity concerning the dosage, treatment duration, objectives and endpoints, but the main objectives were to evaluate the efficacy and safety of curcumin in osteoarthritis treatment. All studies have shown a beneficial effect of curcumin supplementation in the treatment of osteoarthritis, mainly in reduction of pain, stiffness, improvement of physical function, decrease the use of NSAIDs and other painkillers. Results also showed a decrease on inflammatory markers

Conclusion: The studies demonstrated that curcumin is clinically effective as a long term adjuvant treatment of osteoarthritis further to an excellent tolerability. However, large and well-designed randomized controlled trials are warranted to confirm the use of curcumin in osteoarthritis treatment.

References [1] BELCARO, G. et al. Efficacy and Safety od Meriva, a Curcumin-phosphatidylcholine Complex, during extended administration in osteoarthritis patients. Altern Med Rev, v. 15, n. 4, 2010.

[2] CHIN, K.Y. The spice for joint inflammation: anti-inflammatory role of curcumin in treating osteoarthritis. Drug Des Devel ther, v. 10, p.3029-3042, 2016.

[3] MIRZAEI, H. et al. Phytosomal curcumin: a review of pharmacokinetic, experimental and clinical studies. Biomedicine & Pharmacotherapy, p.102-112, p.85, 2017.

[4] MOBASHERI, a. et al. Scientific evidence and rationale for the development of curcumin and resveratrol as nutraceuticals for joint health. Int J Mol Sci, v.13, p.4202-4232, 2012.

ONAKPOYA, I.J. et al. Effectiveness of curcuminoids in the treatment of knee osteoarthritis: a systematic review and meta-analysis of randomized clinical trials. Int J Rheum Dis, v. 20, n. 4, p. 420-433, 2017.

Disclosure of interests: Maria Goulart Employee of: ache Laboratories, Daniela Partar Employee of: ache Laboratories, Luis Cunha Employee of: ache Laboratories, Stevin Zung Employee of: ache Laboratories