Oral glycine administration attenuates diabetic complications in streptozotocin-induced diabetic rats

Life Sci. 2006 Jun 13;79(3):225-32. doi: 10.1016/j.lfs.2005.12.055. Epub 2006 Feb 14.


Diabetes mellitus is a disease characterized by impaired glucose metabolism that leads to retinopathy, brain micro-infarcts and other complications. We have previously shown that oral glycine administration to diabetic rats inhibits non-enzymatic glycation of hemoglobin and diminishes renal damage. In this work, we evaluated the capacity of the amino acid glycine (1% w/v, 130 mM) to attenuate diabetic complications in streptozotocin (STZ)-induced diabetic Wistar rats and compared them with non-treated or taurine-treated (0.5% w/v, 40 mM) diabetic rats. Glycine-treated diabetic rats showed an important diminution in the percentage of animals with opacity in lens and microaneurysms in the eyes. Interestingly, there was a diminished expression of O-acetyl sialic acid in brain vessels compared with untreated diabetic rats (P<0.05). Additionally, peripheral blood mononuclear cells isolated from glycine-treated diabetic rats showed a better proliferative response to PHA or ConA than those obtained from non-treated diabetic rats (P<0.05). Glycine-treated rats had a less intense corporal weight loss in comparison with non-treated animals. Our results suggest that administration of glycine attenuates the diabetic complications in the STZ-induced diabetic rat model, probably due to inhibition of the non-enzymatic glycation process.

MeSH terms

  • Administration, Oral
  • Aneurysm / pathology
  • Aneurysm / prevention & control*
  • Animals
  • Cerebral Arteries / drug effects
  • Cerebral Arteries / pathology*
  • Diabetes Mellitus, Experimental / complications*
  • Diabetic Angiopathies / pathology
  • Diabetic Angiopathies / prevention & control*
  • Glycated Hemoglobin / metabolism
  • Glycine / administration & dosage*
  • Glycosylation / drug effects
  • Male
  • Rats
  • Rats, Wistar
  • Taurine / administration & dosage


  • Glycated Hemoglobin A
  • Taurine
  • Glycine