Natural Products as Anti-glycation Agents: Possible Therapeutic Potential for Diabetic Complications

Abstract

Diabetes mellitus is characterised by hyperglycaemia, lipidaemia and oxidative stress and predisposes affected individuals to long-term complications afflicting the eyes, skin, kidneys, nerves and blood vessels. Increased protein glycation and the subsequent build-up of tissue advanced glycation endproducts (AGEs) contribute towards the pathogenesis of diabetic complications. Protein glycation is accompanied by generation of free radicals through autoxidation of glucose and glycated proteins and via interaction of AGEs with their cell surface receptors (referred to as RAGE). Glycationderived free radicals can damage proteins, lipids and nucleic acids and contribute towards oxidative stress in diabetes. There is interest in compounds with anti-glycation activity as they may offer therapeutic potential in delaying or preventing the onset of diabetic complications. Although many different compounds are under study, only a few have successfully entered clinical trials but none have yet been approved for clinical use. Whilst the search for new synthetic inhibitors of glycation continues, little attention has been paid to anti-glycation compounds from natural sources. In the last few decades the traditional system of medicine has become a topic of global interest. Various studies have indicated that dietary supplementation with combined anti-glycation and antioxidant nutrients may be a safe and simple complement to traditional therapies targeting diabetic complications. Data for forty two plants/constituents studied for anti-glycation activity is presented in this review and some commonly used medicinal plants that possess anti-glycation activity are discussed in detail including their active ingredients, mechanism of action and therapeutic potential.

The Mechanisms of Inhibition of Advanced Glycation End Products Formation through Polyphenols in Hyperglycemic Condition

“…Moreover, a variety of other pathways such as autoxidation of glucose, or ascorbate and lipid peroxidation, can also lead to AGE formation. The yields of these pathways usually are dicarbonyl intermediates, for example MGO, GO, 3-deoxyglucosone, glycolaldehyde, 1-deoxyglucosone [7] and free radicals [8]. Reaction of glyoxal or methylglyoxal with free lysine groups of proteins gives rise to the formation of AGEs such as CML, carboxyethyllysine or methylglyoxal lysine dimer [9].…”

Phytochemical and Biological Evaluation of Ultrasound-Assisted Spray Dried Lonicera etrusca for Potential Management of Diabetes

“…Similar aliquots was combined, concentrated and tested for acute hypoglycemic potentials. The most active aliquot was identified utilizing Bruker 1 H and 13 C NMR (300 MHz) (Germany). For NMR analysis, 100 μL of the active aliquot was mixed three times with 100 μL 100% D2O (0.9%, w/v).…”

“…The DM is marked by a significant increase of oxidative stress as indicated by the decrease in the innate antioxidant enzyme, catalase (CAT), and the re-elevation of CAT levels is an indication of good management of DM [13]. In this study, serum CAT levels decreased in the VEH group from 32.10 ± 0.14 kU/L (normal non-diabetic; NORM) to 19.50 ± 0.10 kU/L (VEH), indicating of high oxidative stress in DM mice, before initiation of treatment (predose) (Figure 8).…”

Comparative Antioxidant Potential and Bioactivity of Maize (Zea mays) Ear Tissues from Different Genotypes

“…Plants having recognized antioxidant and anti-glycation characteristics are getting much interest due to fewer side effects. Some plants have chemicals that can be utilized straight as drugs, which may have hypoglycemic properties and can be useful in the management of diabetic patients (Elosta et al, 2012).…”