Inhibition of Glycation End Products Formation and Antioxidant Activities of Ilex paraguariensis: comparative study of fruit and leaves extracts

Abstract

Objectives: Ilex paraguariensis (Aquifoleaceae) is cultivated to produce “yerba mate”. Due to its nutritional, energizing, hypoglycemic and antioxidant effects, it is used in the elabo ration of food, pharmaceuticals, and cosmetics. The oxidative stress related to protein glycation and production of advanced glycation end products (AGEs) leads to the develop ment of several diseases. The objective of this work was to compare the antioxidant and anti-AGEs activity of a decoction of fruits (F) and leaves (L). Methods: The antioxidant activity was assayed by the DPPH assay and the inhibition o egg yolk lipid peroxidation (ILP), and anti-AGEs activity, through the inhibition of the forma tion of fructosamine (IF), β-amyloid (Iβ), protein carbonylation (IC) and AGEs (IA). Polyphe nols were quantified by HPLC. Results: Maximum response ± SEM: For F 0.01 µg/mL: IF = 42 ± 4%, IC = 17 ± 2% and fo 10 µg/mL: IA = 38 ± 4%, Iβ = 67 ± 7%. For L 0.1 µg/mL: IF = 35 ± 2%, IC = 19 ± 2% and for 100 µg/mL: IA = 26 ± 3%, Iβ = 63.04 ± 2%. The DPPH IC50 = 134.8 ± 14 µg/mL for F and 34.67 ± 3 µg/mL for L. The ILP IC50 = 512.86 ± 50 µg/mL for F and 154.8 ± 15 µg/ mL for L. By HPLC L presented the highest amounts of flavonoids and caffeoylquinic ac ids. F and L showed strong anti-AGEs activity, affecting the early stages of glycation at low concentrations and the late stages of glycation at high concentrations. The highest activ ity for both F and L was seen in the IF and Iβ. F presented the highest anti-AGEs potency L presented the highest antioxidant potency, which was related to the highest content o polyphenols. Conclusion: The fruits of I. paraguariensis could be a source of antioxidant and anti-AGEs compounds to be used with medicinal purposes or as functional food.