Holothuria scabra Jaegar 1833 (Sandfish) extracts and collagens modulate protein-bound Nε-carboxymethyllysine, Nε-carboxyethyllysine and methylglyoxal-derived hydroimidazolone-1 levels

In this study, sea cucumber (Holothuria scabra; Jaegar 1833) extracts and collagens were evaluated for inhibitory properties of protein-bound advanced glycation end products (AGEs). Processed dried sea cucumber with salt extract showed a significant lower IC50 value for fluorescent AGEs (9.19 +/- 7.68 mu g mL(-1), P < 0.05) and fructosamine (503.47 +/- 46.37 mu g mL(-1), P < 0.05), respectively. Processed dried with and without salt extracts significantly reduced the N-epsilon-carboxymethyllysine (CML) and methylglyoxal-derived hydroimidazolone-1 (MG-H1) levels tested at 250 mu g mL(-1). Smoked dried and fresh-dried extracts significantly reduced the N-epsilon-carboxyethyllysine (CEL) levels tested at 250 mu g mL(-1). Pepsin-solubilised collagen and the crude collagen fibrils significantly reduced CML and MG-H1 levels whereas CEL levels were unchanged. Pearson's correlation analysis showed that protein-bound AGE and CML inhibition significantly correlated with the total phenolic and antioxidant activities, respectively. This study provides a strong rationale for further investigation aimed at identifying the active compounds responsible for the observed effects on biomarkers relevant to diabetes.