Vitamin A and the epigenome

The epigenetic phenomena refer to heritable changes in gene expression other than those in the DNA sequence, such as DNA methylation and histone modifications. Major research progress in the last few years has provided further proof that environmental factors, including diet and nutrition, can influence physiologic and pathologic processes through epigenetic alterations, which in turn influence gene expression. This influence is termed nutritional epigenetics, and one prominent example is the regulation of gene transcription by vitamin A through interaction to its nuclear receptor. Vitamin A is critical throughout life. Together with its derivatives, it regulates diverse processes including reproduction, embryogenesis, vision, growth, cellular differentiation and proliferation, maintenance of epithelial cellular integrity and immune function. Here we review the epigenetic role of vitamin A in cancer, stem cells differentiation, proliferation, and immunity. The data presented here show that retinoic acid is a potent agent capable of inducing alterations in epigenetic modifications that produce various effects on the phenotype. Medical benefits of vitamin A as an epigenetic modulator, especially with respect to its chronic use as nutritional supplement, should rely on our further understanding of its epigenetic effects during health and disease, as well as through different generations.

Food allergy and cross-reactivity-chickpea as a test case

Chickpea has become one of the most abundant crops consumed in the Mediterranean and also in western world. Chickpea allergy is reported in specific geographic areas and is associated with lentil and/or pea allergy. We investigated cross-reactivity between chickpea and pea/lentil/soybean/hazelnut. The IgE-binding profiles of chickpea globulin and pea/lentil/soybean/hazelnut extracts were analyzed by immunoblotting and immunoblot-inhibition studies. Inhibition-assay with pea/lentil completely suppressed IgE-binding to chickpea globulin allergens, while not so in the reciprocal inhibition. Pre-absorption of sera with chickpea globulin caused the disappearance of IgE-binding to protein on an immunoblot of soybean/hazelnut protein extract. These results suggest that cross-reactivity exists between chickpea and pea/lentil/soybean/hazelnut. Chickpea allergy is associated with lentil and/or pea allergy, but evidently may not present independently. This, together with the described asymmetric cross-reactivity and phylogenetic aspects, suggest that chickpea allergy is merely an expression of cross-reactivity, caused by pea and/or lentil as the "primary" allergen.

The potential use of chickpeas in development of infant follow-on formula

BACKGROUND

Undernutrition during childhood is a common disorder in the developing countries, however most research has focussed much on its treatment rather than its prevention.

OBJECTIVE

We investigated the potential of using chickpeas in infant follow-on formula production against the requirements of WHO/FAO on complementary foods and EU regulations on follow-on formula.

METHODS

Chickpeas were germinated for 72 hours followed by boiling, drying and dehulling in order to minimise associated anti-nutrition factors. Saccharifying enzymes were used to hydrolyse starch to maltose and the resulting flours were analysed for their protein content and amino acid profile.

RESULTS

The protein content (percentage) increased from 16.66 ± 0.35 and 20.24 ± 0.50 to 20.00 ± 0.15 and 21.98 ± 0.80 for the processed desi and kabuli cultivar compared to raw chickpeas, respectively (P < 0.05). There was insignificant change (P = 0.05) in amino acid profile following processing and the resulting flour was found to meet the amino acid requirements of WHO/FAO protein reference for 0-24 month's children.

CONCLUSION

The designed chickpea based infant follow-on formula meets the WHO/FAO requirements on complementary foods and also the EU regulations on follow-on formula with minimal addition of oils, minerals and vitamins. It uses chickpea as a common source of carbohydrate and protein hence making it more economical and affordable for the developing countries without compromising the nutrition quality.

Vicilin and the basic subunit of legumin are putative chickpea allergens

IgE-mediated reactions to food allergens constitute a major health problem in industrialized countries. Chickpea is consumed in Mediterranean countries, and reportedly associated with IgE-mediated hypersensitivity reactions. However, the nature of allergic reactions to chickpea has not been characterized. A serum pool from paediatric patients allergic to chickpeas was used to detect IgE-binding proteins from chickpea seeds by immunoassay and immunoblot inhibition assay. Protein samples enriched in chickpea legumin and vicilin were obtained by anion exchange chromatography, and were identified by mass spectrometric analysis. IgE-immunoassays of globulin fractions from chickpeas revealed that vicilin (50 kDa) and the basic subunit of legumin (20 kDa) were bound by IgE from patient sera. Pea and lentil protein extracts strongly inhibited the IgE binding to chickpea globulin. We speculate that vicilin and the basic subunit of legumin are major chickpea allergens. Also, the globulin fraction of chickpea likely cross-reacts with the allergenic proteins of pea and lentil.