Glycine improves biochemical and biomechanical properties following inflammation of the achilles tendon

Anat Rec (Hoboken). 2015 Mar;298(3):538-45. doi: 10.1002/ar.23041. Epub 2014 Sep 2.


Tendinopathy of the Achilles tendon is a clinical problem that motivates the scientific community to search for treatments that assist in restoring its functional properties. Glycine has broad biological effects, acting as a modulator of the inflammatory cascade, and is the predominant amino acid in collagen. A 5% glycine diet provided beneficial effects against toxicity and inflammation since glycine may restructure the collagen molecules faster due to its broad anti-inflammatory effects. The purpose was analyze the effects of a 5% glycine diet in rats as a treatment for the inflammatory process. The experimental groups were as follows: C (control group), G1 and G3 (inflammatory group), and G2 and G4 (glycine+inflammatory group). G1 and G2 were euthanized 8 days following injury, and G3 and G4 were euthanized 22 days following injury. The concentrations of hydroxyproline, non-collagenous proteins, and glycosaminoglycans, as well as the activity of MMP-2 and -9 were analyzed. Biomechanical and morphological tests were employed. Higher concentrations of hydroxyproline and glycosaminoglycans were found in G4 and an increased activity of MMP-2 was found in G2. Higher birefringence was noted in group G2. The biomechanical results indicated that the tendon was more resistant to loading to rupture upon treatment with a glycine diet in group G4. Glycine induced the synthesis of important components of the tendon. A rapid remodeling was noted when compared with the inflamed-only groups. These data suggest that glycine may be a beneficial supplement for individuals with inflammation of the Achilles tendon.

Keywords: achilles tendon; extracellular matrix; glycine; inflammatory process; tendinopathy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Achilles Tendon / drug effects*
  • Animals
  • Dietary Supplements
  • Glycine / drug effects
  • Glycine / therapeutic use*
  • Male
  • Rats, Wistar
  • Tendinopathy / diet therapy*


  • Glycine