Prebiotic Intake during Pregnancy Mitigates Long-Term Antibiotic Disturbances in the Gut-Breast Axis and Regulates Mammary Gland Development

This study investigates the long-term effects of prenatal and postnatal exposure to low-dose penicillin (LDP) on immune responses and mammary gland development in mice, along with the potential protective role of the prebiotic AHCC. Pregnant dams were treated with LDP and/or AHCC from late gestation to weaning.

Immune markers and blood-milk barrier integrity were assessed in dams, while offspring were evaluated for immune profiles, mammary gland morphology, and epigenetic alterations. LDP exposure triggered inflammation and disrupted DNA methylation in key regulatory genes and microRNAs related to mammary development and the ERK/MAPK pathway. AHCC mitigated these effects, supporting its immunomodulatory and protective potential.