Collagen is a protein containing several dibasic amino acids and has a slow turnover rate and is a strong candidate for extensive modification by glycation. Crosslinking is important in stabilizing the collagen fibrils. Cross linking contributes to the tensile strength of tissues such as tendon by decreasing the permeability and elasticity of extracellular matrix. Extensive cross linking of collagen however causes changes in its structure and the mechanical properties can be pathological. Such changes have been reported in aging and in various pathological conditions including diabetes.Curcuma longa is commonly used in the treatment of diabetes by ayurvedic physicians. Curcumin is a biologically active component isolated from the rhizome of Curcuma longa that possess antihyperglycemic activity, hypolipidemic action and anti - renal lesion effect. The use of curcumin is recommended for prevention of advanced glycatedendproducts (AGEs) accumulation and the associated complications of diabetes. Tetrahydrocurcumin (THC) is one of the major colorless metabolite of curcumin. THC has been reported to exhibit the same physiological and pharmacological properties of curcumin.In diabetic rats, hydroxyproline and collagen content as well as its degree of cross-linking were increased, as shown by increased extent of glycation, collagen-linked fluorescence, neutral salt collagen, decreased acid and pepsin solubility.Administration of THC for 45 days to diabetic rats significantly reduced the accumulation and cross-linking of collagen.
