Different maize (Zea mays L.) varieties have been used for thousands of years as a healthy food source in Mesoamerica including pigmented maize. Maize ingestion could contribute to the reduction in the rate of non-communicable diseases and, in turn, to its function as an adjuvant in their management. These diseases are mainly associated with oxidative stress, which is characterized by a redox cell imbalance produced due to pro-oxidant molecules accumulation, inducing irreversible damages. Although the endogenous antioxidant defense system is effi cient, exogenous antioxidants are necessary to help to prevent this damage. Bioactive compounds, like anthocyanins, contained in dietary plants exert a major activity against oxidative stress. Could the maize anthocyanins play a curative, preventive or complementary role in the treatment of chronic diseases? Here, we describe the occurrence of anthocyanins from pigmented maize and their chemical structures. Furthermore, the biosynthesis, bioavailability, and stability are also summarized. Finally, many in vitro and in vivo studies of maize anthocyanins are discussed that demonstrated their nutraceutical potential, antioxidant capacity, and other biological effects. Given the importance of the biological properties of maize anthocyanins, it is necessary to understand the current knowledge and propose further research or clinical studies which allows us to better elucidate the biological mechanism of maize anthocyanins derivatives of several varieties and processes of cooking and combination with other ingredients to enhance their nutritional and health benefi ts.

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Maize is one of the most important crops for human and animal consumption and contains a chemical arsenal essential for survival: flavonoids. Moreover, flavonoids are well known for their beneficial effects on human health. In this review, we decided to organize the information about maize flavonoids into three sections. In the first section, we include updated information about the enzymatic pathway of maize flavonoids. We describe a total of twenty-one genes for the flavonoid pathway of maize. The first three genes participate in the general phenylpropanoid pathway. Four genes are common biosynthetic early genes for flavonoids, and fourteen are specific genes for the flavonoid subgroups, the anthocyanins, and flavone C-glycosides. The second section explains the tissue accumulation and regulation of flavonoids by environmental factors affecting the expression of the MYB-bHLH-WD40 (MBW) transcriptional complex. The study of transcription factors of the MBW complex is fundamental for understanding how the flavonoid profiles generate a palette of colors in the plant tissues. Finally, we also include an update of the biological activities of C3G, the major maize anthocyanin, including anticancer, antidiabetic, and antioxidant effects, among others. This review intends to disclose and integrate the existing knowledge regarding maize flavonoid pigmentation and its relevance in the human health sector.

Background HNF1A gene regulates liver‐specific genes, and genes that have a role in glucose metabolism, transport, and secretion of insulin. HNF1A gene mutations are frequently associated with type 2 diabetes. HNF1A protein has three domains: the dimerization domain, the DNA‐binding domain, and the trans‐activation domain. Some mutations in the dimerization or DNA‐binding domains have no influence on the normal allele, while others have dominant negative effects. The I27L, A98V, and S487N polymorphisms are common variants of the HNF1A gene; they have been found in T2D and non‐diabetic subjects.Methods and ResultsWe searched for mutations in the first three exons of the HNF1A gen in an Amerindian population of 71 diabetic patients. DNA sequencing revealed the previously reported I27L polymorphism (c.79A>C) in 53% of diabetic patients and in 67% of the control group. Thus, the I27L/L27L polymorphism might be a marker of Amerindians. In addition, we found the c.422_423InsT mutation in the HNF1A gene of one patient, which had not been previously reported. This mutation resulted in a frame shift of the open reading frame and a new translation stop in codon 187, leading to a truncated polypeptide of 186 amino acids (Q141Hfs*47). This novel mutation affects the DNA‐binding capacity of the mutant HNF1A protein by EMSA; its intracellular localization by fluorescence and confocal microscopy, and a dominant‐negative effect affecting the DNA‐binding capacity of the normal HNF1A by EMSA. We also studied the homology modeling structure to understand the effect of this mutation on its DNA‐binding capacity and its dominant negative effect.ConclusionThe HNF1A Q141Hfs*47 mutant polypeptide has no DNA‐binding capacity and exerts a dominant negative effect on the HNF1A protein. Therefore, it might produce severe phenotypic effects on the expression levels of a set of β‐cell genes. Consequently, its screening should be included in the genetic analysis of diabetic patients after more functional studies are performed.

Although the cladodes of Nopalea cochenillifera are used in Mexican traditional medicine to treat diabetes and various other diseases, its antihyperglycaemic properties, phenolic content, and antioxidant activity are not well documented. Thus, we determined the activity of a single dose of fresh, blended cladodes on postprandial glycaemia in rats after a starch load. We prepared a methanolic extract of N. cochenillifera cladodes and measured its phenolic content, antioxidant capacity, and α-glucosidase inhibitory activity. The antihyperglycaemic effect of blended cladodes was similar to that of acarbose when considering the changes in glucose levels from baseline. Furthermore, the methanolic extract contained a considerable amount of phenolic compounds and exhibited antioxidant activity in the DPPH assay, but did not markedly inhibit α-glucosidase and had a low antioxidant effect in the ABTS test.