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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Animals, Newborn, Colorectal Neoplasms, Dietary Supplements, Disease Models, Animal, Female, Folic Acid, Humans, Male, Mice, Mice, Inbred C57BL, Mice, Mutant Strains, Pregnancy, Prenatal Exposure Delayed Effects, Riboflavin, Vitamin B 12, Vitamin B 6, Vitamin B Complex, Vitamin D Deficiency, Wnt Signaling Pathway.
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Does maternal B vitamin supplementation from preconception through weaning suppress intestinal tumorigenesis in Apc1638N mouse offspring? Context: Variations in the intake of folate are capable of modulating colorectal tumorigenesis; however, the outcome appears to be dependent on timing. This study sought to determine the effect of altering folate (and related B vitamin) availability during in-utero development and the suckling period on intestinal tumorigenesis. Female wildtype mice were fed diets either mildly deficient, replete or supplemented with vitamins B(2), B(6), B(12) and folate for 4 weeks before mating to Apc(1638N) males. Females remained on their diet throughout pregnancy and until weaning. After weaning, all Apc(1638N) offspring were maintained on replete diets for 29 weeks. At 8 months of age tumour incidence was markedly lower among offspring of supplemented mothers (21%) compared with those of replete (59%) and deficient (55%) mothers (p=0.03). Furthermore, tumours in pups born to deficient dams were most likely to be invasive (p=0.03). The expression of Apc, Sfrp1, Wif1 and Wnt5a--all of which are negative regulatory elements of the Wnt signalling cascade--in the normal small intestinal mucosa of pups decreased with decreasing maternal B vitamin intake, and for Sfrp1 this was inversely related to promoter methylation. β-Catenin protein was elevated in offspring of deficient dams.
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These changes indicate a de-repression of the Wnt pathway in pups of deficient dams and form a plausible mechanism by which maternal B vitamin intake modulates tumorigenesis in offspring. These data indicate that maternal B vitamin supplementation suppresses, while deficiency promotes, intestinal tumorigenesis in Apc(1638N) offspring. Final Decision: yes