β-cryptoxanthin–biofortified hen eggs enhance vitamin A status when fed to male Mongolian gerbils
Consumption of provitamin A carotenoid biofortified crops, such as maize, supports vitamin A (VA) status in animals and humans. Laying hens that consume β-cryptoxanthin–biofortified maize deposit β-cryptoxanthin into egg yolk.
We investigated whether β-cryptoxanthin–biofortified egg consumption would affect VA status of male Mongolian gerbils (Meriones unguiculatus) compared with white-yolked eggs.
β-Cryptoxanthin–biofortified egg yolk, produced in hens fed biofortified orange maize or tangerine-fortified maize feeds, was freeze-dried and fed to gerbils. White-yolked eggs were produced by feeding white maize to hens. Gerbils (n = 57) were fed VA-deficient feed for 28 d. After baseline (n = 7), treatments (n = 10/group) included oil control (VA−); 16.7% orange maize–biofortified, tangerine-fortified, or white-yolk egg feeds; or retinyl acetate as positive control (VA+) matched to daily preformed retinol intake from the eggs for 30 d. Preformed retinol did not differ between the egg yolks. Gerbil liver retinol, lipid, fatty acids, and cholesterol were determined.
Liver retinol concentration (0.13 ± 0.03 µmol/g) and total hepatic VA (0.52 ± 0.12 µmol) were higher in gerbils fed orange maize–biofortified eggs than in all other groups. The VA− group was severely VA deficient (0.018 ±0.010 µmol/g; P < 0.05). Liver retinol was similar among VA+, tangerine-egg–, and white-egg–fed gerbils, but retinol reserves were higher in tangerine-egg–fed gerbils (0.35 ± 0.11 μmol) than in VA+ or VA− gerbils or at baseline (P < 0.05). Liver fat was 3.6 times (P < 0.0001) and cholesterol was 2.1 times (P < 0.004) higher in egg-fed groups that experienced hepatosteatosis. Liver fatty acid profiles reflected feed, but retinyl ester fatty acids did not.
The preformed retinol in the eggs enhanced gerbil VA status, and the β-cryptoxanthin–biofortified eggs from hens fed orange maize prevented deficiency. Biofortified maize can enhance VA status when consumed directly or through products from livestock fed orange maize.
Heying EK, Ziemer KL, Tanumihardjo JP, Palacios-Rojas N, Tanumihardjo SA. 2018. β-cryptoxanthin–biofortified hen eggs enhance vitamin A status when fed to male Mongolian gerbils. The Journal of Nutrition 148(8): 1236-1243. https://doi.org/10.1093/jn/nxy117