Abstract

The Brazil nut (Bertholletia excelsa, H.B.K.) originating from the Amazon region is one of the richest known sources of selenium (Se), a micronutrient that is essential and required for optimal physiological functioning. This mineral presents several health benefits, including improvement of the redox cellular status and maintenance of genomic stability. Knowing that type 2 diabetes mellitus (T2D) is strongly linked to oxidative stress and consequently DNA damage, the aim of this study was to assess the ex vivo antioxidative effects of Se through Brazil nut consumption and its potential in preventing oxidative DNA damage induced by H₂O₂. In order to accomplish this, the Comet assay (single-cell gel electrophoresis) was used to measure DNA damage in peripheral blood cells harvested before and after supplementation with Brazil nut. Comet assay was also applied ex vivo to measure the potential of Se to prevent oxidative damage to DNA induced by H₂O₂ in blood of type 2 diabetes patients collected before and after six months of supplementation with Brazil nut. We found that supplementation with Brazil nuts significantly increased serum Se levels. Furthermore, we observed a significant increase in fasting blood glucose after six months of consuming Brazil nuts; however, no significant effect was observed on the levels of glycated hemoglobin. Finally, we noticed that the cells were more resistant to H₂O₂-induced DNA damage after six months of supplementation with Brazil nut. Thus, consumption of Brazil nuts could decrease oxidative DNA damage in T2D patients, probably through the antioxidative effects of Se.

摘要

源自亚马逊地区的巴西坚果 ( Bertholletia excelsa, HBK ) 是已知最丰富的硒 (Se) 来源之一，硒是一种微量营养素，对最佳生理功能至关重要。这种矿物质具有多种健康益处，包括改善氧化还原细胞状态和维持基因组稳定性。知道 2 型糖尿病 (T2D) 与氧化应激和 DNA 损伤密切相关，本研究的目的是评估硒通过巴西坚果摄入的离体抗氧化作用及其在预防 H 诱导的氧化 DNA 损伤方面的潜力₂ O ₂. 为了做到这一点，彗星试验（单细胞凝胶电泳）用于测量补充巴西坚果前后采集的外周血细胞中的 DNA 损伤。彗星试验也用于离体测量硒防止由 H ₂ O _{2诱导的 DNA 氧化损伤的潜力}在补充巴西坚果六个月之前和之后收集的 2 型糖尿病患者的血液中。我们发现补充巴西坚果可显着提高血清硒水平。此外，我们观察到在食用巴西坚果六个月后空腹血糖显着增加；然而，没有观察到对糖化血红蛋白水平的显着影响。最后，我们注意到在补充巴西坚果六个月后，这些细胞对 H ₂ O _{2诱导的 DNA 损伤具有更强的抵抗力。}因此，食用巴西坚果可以减少 T2D 患者的 DNA 氧化损伤，这可能是通过硒的抗氧化作用。