Phytochemical profile, anti-glycation effect, and advanced glycation end-products protein cross-link breaking ability of Sclerocarya birrea stem-bark crude extracts

Introduction: Sclerocarya birrea stem-bark is widely used for the treatment of many medical conditions. Advanced glycation end-products (AGEs) are implicated in the pathogenesis of vascular complications of diabetes mellitus. The study, other than phytochemical composition, evaluated the anti-glycation and AGEs-protein cross-link breaking effects of S. birrea stem-bark extracts. Methods: Different S. birrea extracts and aminoguanidine (used as control) were incubated with bovine serum albumin (BSA) and glucose/fructose at ۳۷oC for ۴۰ days. Amounts of fluorescent AGEs (FAGEs) and immunogenic AGEs formed were determined. Anti-glycation activity percentage of each extract and aminoguanidine was calculated. Their AGEs-protein cross-link breaking abilities were also assessed. Standard techniques were employed for phytochemical screening. Volatile compounds were identified by means of gas chromatography mass spectrometry (GC-MS). Results: S. birrea stem-bark n-hexane extract was statistically more effective than aminoguanidine against the formation of total immunogenic AGEs (P<۰.۰۵). For FAGEs, ethyl acetate, methanol, and water extracts exerted significantly higher anti-glycation effects than aminoguanidine (P<۰.۰۰۱). Methanol extract exhibited the highest anti-glycation effect with an average IC۵۰ value of ۰.۱۴۲ mg/mL against FAGEs. All extracts were effective in releasing BSA from the preformed collagen-AGEs-BSA cross-links. GC-MS enabled the identification of many biologically important compounds, including campesterol, stigmasterol, and ۱-heptatricontanol. Conclusion: S. birrea stem-bark has a potential for usage in the management of complications in uncontrolled glucose metabolism.

Keywords:

Anti-glycation , Medicinal plant , Phytochemistry , Diabetic vascular complications Protein glycation