β-Carotene supplementation decreases placental transcription of LDL receptor-related protein 1 in wild-type mice and stimulates placental β-carotene uptake in marginally vitamin A-deficient mice

J Nutr. 2012 Aug;142(8):1456-62. doi: 10.3945/jn.112.162677. Epub 2012 Jun 27.

Abstract

The human diet contains β-carotene as the most abundant precursor of vitamin A, an essential nutrient for embryogenesis. Our laboratory previously showed the importance of β-carotene metabolism via β-carotene-15,15'-oxygenase (CMOI) to support mouse embryonic development. However, the mechanisms regulating embryonic acquisition and utilization of β-carotene from the maternal circulation via placenta remain unknown. We used wild-type (WT) and Lrat(-/-)Rbp(-/-) (L(-/-)R(-/-)) mice, the latter being a model of marginal vitamin A deficiency. Pregnant dams, fed a nonpurified diet sufficient in vitamin A throughout life, were i.p. supplemented with β-carotene or vehicle at 13.5 d postcoitum (dpc). Effects of this acute maternal supplementation on retinoid and β-carotene metabolism in maternal (serum, liver) and developing tissues (placenta, yolk sac, embryo) were investigated at 14.5 dpc. We showed that, upon supplementation, placental β-carotene concentrations were greater in L(-/-)R(-/-) than in WT mice. However, the retinoid (retinol and retinyl ester) concentrations remained unchanged in placenta (and in all other tissues analyzed) of both genotypes upon β-carotene administration. We also showed that upon a single i.p. β-carotene supplementation, placental LDL receptor-related protein (Lrp1) mRNA expression was lower in WT mice, and embryonic CmoI mRNA expression was greater in L(-/-)R(-/-) mice. Together, these data suggest a potential role of LRP1 in mediating the uptake of β-carotene across the placenta and that even a marginally impaired maternal vitamin A status may influence uptake and utilization of β-carotene by the placenta and the embryo.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animal Feed / analysis
  • Animal Nutritional Physiological Phenomena
  • Animals
  • Diet / veterinary
  • Dietary Supplements
  • Embryo, Mammalian / metabolism
  • Female
  • Gene Expression Regulation / drug effects
  • Low Density Lipoprotein Receptor-Related Protein-1 / genetics
  • Low Density Lipoprotein Receptor-Related Protein-1 / metabolism*
  • Maternal Nutritional Physiological Phenomena
  • Mice
  • Mice, Knockout
  • Placenta / metabolism*
  • Pregnancy
  • Random Allocation
  • Vitamin A Deficiency / metabolism*
  • beta Carotene / administration & dosage*
  • beta Carotene / metabolism*

Substances

  • Low Density Lipoprotein Receptor-Related Protein-1
  • beta Carotene