Lactose on the basolateral side of mammary epithelial cells inhibits milk production concomitantly with signal transducer and activator of transcription 5 inactivation.

Mammary epithelial cells (MECs) are the only cells capable of synthesizing lactose. During lactation, alveolar MECs secrete lactose through the apical membrane into the alveolar lumen, whereas alveolar tight junctions (TJs) block the leakage of lactose into the basolateral sides of the MECs. However, lactose leaks from the alveolar lumen into the blood plasma in the mastitis and after weaning.

Adverse Effects of High Temperature On Mammary Alveolar Development In Vitro.

In the mammary glands during pregnancy, the alveolar buds are first branched from the mammary ducts after which they form the alveolar luminal structure for milk production postparturition. Body temperature could increase for several reasons, such as infectious disease and heat stress. We have previously reported that high temperature adversely effects on the lactation capacity of mouse mammary epithelial cells (MECs).

Isoflavones and their metabolites influence the milk production ability of bovine mammary epithelial cells in a type-specific manner.

Dairy cows feed on isoflavones as physiologically active substances present in legumes. However, the influences of isoflavones (biochanin A, genistein, formononetin, and daidzein) and their metabolites (p-ethylphenol and equol) on milk components production, tight junctions (TJs), and their regulatory pathways are unclear in bovine mammary epithelial cells (BMECs). In this study, we investigated the influences of isoflavones and their metabolites in BMECs using an in vitro culture model.

IL-1β is a key inflammatory cytokine that weakens lactation-specific tight junctions of mammary epithelial cells.

In lactating mammary glands, alveolar mammary epithelial cells (MECs) produce milk and form less-permeable tight junctions (TJs). However, alveolar TJs are weakened with a reduction in milk production in mammary glands due to mastitis or weaning in the presence of high levels of IL-1β, IL-6, or TNF-α. In this study, using in vitro cultured model of MECs with milk-producing ability and lactation-specific TJs, we investigated whether the aforementioned cytokines affect MEC TJs.

Genistein Directly Represses the Phosphorylation of STAT5 in Lactating Mammary Epithelial Cells.

Genistein is a soy isoflavone and shows various physiological activities, such as affinities for estrogen receptors (ERs) and inhibitory effects on the epidermal growth factor receptor (EGFR) pathway. A previous study reported that genistein downregulates milk production ability in mammary epithelial cells (MECs) while decreasing the phosphorylation of STAT5. The ER and EGFR pathways indirectly regulate STAT5.

Adverse effects of LPS on membrane proteins in lactating bovine mammary epithelial cells.

Mastitis causes a decrease in milk yield and abnormalities in milk components from dairy cows. Escherichia coli and the E. coli lipopolysaccharide (LPS) cell wall component directly downregulate milk production in bovine mammary epithelial cells (BMECs).

Menthol from Mentha piperita Suppresses the Milk Production of Lactating Mammary Epithelial Cells In Vivo and In Vitro.

Scope: Peppermint is traditionally used as an antigalactagogue in breastfeeding women. However, the suppressive mechanism remains unclear. The authors investigate whether and how peppermint influences milk production at the cellular and molecular levels.

Distinct Expression Patterns of Fibrillar Collagen Types I, III, and V in Association with Mammary Gland Remodeling during Pregnancy, Lactation and Weaning.

The mammary gland structurally and functionally remodels during pregnancy, during lactation and after weaning. There are three types of fibrillar collagens, types I, III, and V, in mammary stromal tissue. While the importance of the fibrillar structure of collagens for mammary morphogenesis has been suggested, the expression patterns of each type of fibrillar collagen in conjunction with mammary remodeling remain unclear.

Adverse Effects of Coumestrol and Genistein on Mammary Morphogenesis and Future Milk Production Ability of Mammary Epithelial Cells.

Isoflavones are a class of flavonoids present in legumes and are called phytoestrogens because of their estrogen-like activity. Endogenous estrogen is well known to regulate mammary gland morphogenesis during pregnancy. Each isoflavone also has different physiological activities.