Table 1.

Overview of principal nutraceutical and their properties (Glc-N-CS: glucosamine and chondroitin sulphate; vit C: vitamin C; Col I: collagen type 1; Col III collagen type 3; AAKG: L-arginine-α-keto-glutarate; NOS: nitric oxide synthase; NO: nitric oxide; 5-LO: 5-lipoxygenase; TNFα: tumor necrosis factor α; IL-1/2/4/6: interleukin 1/2/4/6; IFNγ: interferon γ; MSM: methilsulfonil methane; MDA: malonyldialdehyde; GSSG: oxidized gluthation).

Nutraceutical	Biological effect
Glucosamine and chondroitin sulphate (GlcN-CS)	Increase collagen synthesis, ameliorate mechanical properties, organization of collagen bundles and resistence to fatigue, helpful in the management of pain.
Vitamin C (Vit C)	Stimulate hydroxyproline synthesis of procollagen, enhance angiogenesis and maturation of Col III to Col I fibers, anti-inflammatory and antioxidant effect.
Collagen I (Col I)	Increase mechanical properties, beneficial effects on collagen-rich tissues.
L-arginine-α-keto-glutarate	Substrate of NOS, increase NO levels and collagen synthesis.
Curcumin	Neoangiogenesis and apotosis inhibitor, antioxidant effect, stimulate tenocytes survival.
Boswellic acid	Elastase and 5-LO activity inhibition, reduce TNFα, IL-1, IL-2, IL-4, IL- 6 e INFγ levels.
Methilsulfonilmethane (MSM)	Analgesic, anti-inflammatory and antioxidant effects, reduce MDA and GSSG levels.
Bromelain	Decrease lymphocytes rolling, anti edema, antioxidant and immunosuppressive effects, reduce MDA levels.