Antioxidant Activity and In Vitro Antiglycation of the Fruit of Spondias purpurea.

Hyperglycemia in diabetes mellitus causes irreversible life-threatening micro- and macrovascular complications. There is evidence that the glycation reaction leads to a chemical modification of the proteins contributing to the complications of diabetes. It is known that advanced glycation end products (AGEs) are formed by glycation and oxidation reactions called glycoxidation. CML, a nonfluorescent AGE, has become a biomarker of glycoxidative damage; other AGEs appear to induce oxidative stress, which results in cytotoxicity. To determine antioxidant activity, the FRAP, DPPH, and TEAC tests were used, as well as the polyphenols content using Folin-Ciocalteu's method. To evaluate the antiglycation activity, the BSA/glucose system was used, and the fructosamine concentration, protein carbonyl content, thiol, and CML groups were determined. The results obtained show that the hexane extract of the fruit of Spondias purpurea (CFH) effectively inhibits the glycation reaction, in addition to increasing the thiol groups and decreasing levels of fructosamine, protein carbonyl, and CML. In addition, CFH presented significant antioxidant activity. CFH inhibits the glycation reaction; therefore, it can help prevent complications related to AGEs in diabetes mellitus; it also reduces oxidative stress and is effective in protecting proteins from oxidative damage.

In Vitro Inhibitory Activity of Acca sellowiana Fruit Extract on End Products of Advanced Glycation.

INTRODUCTION: Hyperglycemia plays an important role in the pathogenesis of diabetic complications, as it increases protein glycation, as well as the progressive accumulation of advanced glycation end products (AGEs), which are complex structures that produce fluorescence. The glycation reaction raises the levels of protein carbonyl, N ε-(carboxymethyl)lysine (CML), and fructosamine and decreases the level of thiol groups. METHODS: In the present study, the antiglycation activity was determined by fluorescence intensity using the bovine serum albumin (BSA)/glucose, CML method, and the level of fructosamine. The oxidation of proteins was determined by the carbonyl protein content and thiol groups. RESULTS: The results show that the hexane extract of Acca sellowiana (FOH) at different concentrations (0.30-5 mg/ml) significantly inhibited the formation of AGEs in the BSA/glucose model during the 4 weeks of the study. FOH reduced the levels of fructosamine and CML. Our results showed a significant effect of FOH in the prevention of oxidative damage of proteins, as well as an effect on the oxidation of thiol groups and carbonyl proteins. CONCLUSION: The present study indicates that FOH is effective in inhibiting the glycation of proteins in vitro, so it can prevent or ameliorate the chronic conditions of diabetes associated with the formation of AGEs.