Inhibition of Protein Glycation and OH <sup>•</sup>-Induced Protein Fragmentation by Fenugreek Phytochemicals

Abstract

Glycation of proteins and generation of advanced glycation end products (AGEs) are the fundamental causes in the development of oxidative stress-induced protein modification and diabetes complications. The hyperglycemic condition causes non-enzymatic protein glycation, initiated by the reaction between the carbonyl groups of sugars with the amino groups of proteins forming the amadori products. Amadori products induce further oxidation, generating dicarbonyl compounds to form cross-linking fluorescent and non-fluorescent adduct called AGEs. In this study, the protective effect of fenugreek phytochemicals on protein glycation and oxidation-induced protein fragmentation was evaluated. Fenugreek phytochemicals (phenolics and alkaloids) protected oxidation-induced protein fragmentation and inhibited protein glycation. They also prevented the formation of fluorescent and non-fluorescent AGEs, and glycation-mediated protein conformational changes. Fenugreek phytochemicals effectively scavenged reactive carbonyl intermediates and decreased protein thiol modification. Collectively, these results suggest the potential utility of fenugreek phytochemicals as functional food ingredients for the control of diabetes and its complications. Funding Information: This work is financially supported by the planning commission and Council of Scientific and Industrial Research, Govt. India, as part of 12th- five-year plan project (BSC-0404). Declaration of Interests: The authors declare that they have no competing interests.