Supplemental β-carotene increases IgA-secreting cells in mammary gland and IgA transfer from milk to neonatal mice

Abstract

Mortality of neonates continues to be a major problem in humans and animals. IgA provides protection against microbial antigens at mucosal surfaces. Although b-carotene supplementation has been expected to enhance retinoic acid-mediated immune response in neonates, the exact mechanism by which b-carotene enhances IgA production is still unclear. We investigated the effect of supplemental b-carotene for maternal mice during pregnancy and lactation on IgA antibody-secreting cells (ASC) in mammary gland and guts and on IgA transfer from milk to neonatal mice. Pregnant mice were fed untreated or 50 mg/kg b-carotene-supplemented diets from 6·5 d postcoitus (dpc) to 14 d postpartum (dpp). Supplemental b-carotene increased the numbers of IgA ASC in mammary gland (P, 0·05) and ileum (P, 0·001), and also mRNA expression of IgA C-region in ileum (P,0·05) of maternal mice at 14 dpp, but few IgA ASC were detected in mammary gland at 17·5 dpc. IgA concentration in stomach contents, which represents milk IgA level, was significantly higher (P,0·01) in neonatal mice born to b-carotene-supplemented mothers at 7 and 14 dpp, and IgA concentration in serum, stomach contents and faeces increased (P,0·001) drastically with age. These results suggest that b-carotene supplementation for maternal mice during pregnancy and lactation is useful for enhancing IgA transfer from maternal milk to neonates owing to the increase in IgA ASC in mammary gland and ileum during lactation.

Carotenoid content, its stability during drying and the antioxidant activity of commercial coriander (Coriandrum sativum L.) varieties

“…It is known that VAD and AMD are primarily due to inadequacy of provitamin A (mainly β-carotene) and other macular pigments in the diet. Another serious problem faced by developing countries is mortality and morbidity of neonates where supplemental vitamin A and β-carotene enhance the immune system in neonates (Nishiyama, Sugimoto, Ikeda, & Kume, 2010). Above all, β-carotene is generally regarded as the most commercially important and widely used carotenoid in food as a coloring agent and as an antioxidant both in the food and after its ingestion (Szpylka et al, 2005).…”

Effects of coumestrol administration to maternal mice during pregnancy and lactation on immunoblogulin A‐secreting cells in mammary glands

“…On the other hand, β‐carotene supplementation may have a predominant effect on IgA production in the ileum, although supplemental β‐carotene increased the numbers of IgA ASC in mammary glands (Nishiyama et al . ). The mammary gland is colonized primarily by IgA‐containing B cells during lactation (Tanneau et al .…”

“…According to previous studies (Nishiyama et al . ,b), all the neonatal mice were alive by 7 dpp, and the numbers of pups for each mother were reduced to five female and five male neonatal mice at 7 dpp. Then, five female and five male neonatal mice born to each mother and the maternal mice were dissected at 14 dpp.…”

“…According to previous studies (Nishiyama et al . ,b), IgA concentration in stomach contents was represented as milk IgA level. The samples were separately pooled for female or male neonatal mice born to each mother at 14 dpp.…”

“…In previous studies (Nishiyama et al . ,b), supplemental β‐carotene for maternal mice during pregnancy and lactation increased messenger RNA (mRNA) expression of IgA C‐region and the number of IgA ASC in the ileum during lactation, but in the mammary gland, β‐carotene supplementation only increased the number of IgA ASC. However, the mechanism of phytoestrogen for enhancing IgA ASC accumulation in mammary glands of lactating animals is still unclear, although supplemental phytoestrogen has been expected to enhance ER‐mediated immune response in mammary glands.…”