title: Decrease of lactogenic hormones induce epithelial-mesenchymal transition via TGFβ1 and arachidonic acid during mammary gland involution.
abstract: During mammary gland involution, the epithelial mesenchymal transition (EMT) process plays an important role in tissue remodelling and in the termination of milk production. Transforming growth factor β (TGFβ) has been known as a central inducer to EMT and contributor to the mammary gland involution. However, the whole mechanism has accomplished the EMT process in mammary gland is still unclear. Here, we show that arachidonic acid, one of the major products in milk, is new player to control the EMT together with TGFβ during mammary gland involution. Firstly, we observed decrease in CDH1 (epithelial marker gene) expression and increases in VIM and TWIST1 (mesenchymal marker genes), TGFB1, and PLCG2 (arachidonic acid synthesis gene) at involution. In epithelial cells culture experiments, depletion of lactogenic hormones to mimic the involution induced TGFβ1 and PLCG2 expressions. Treatment with arachidonic acid in epithelial cells increased VIM and TWIST1 expressions without decrease of CDH1 expression, while TGFβ1 decreased CDH1 and increased VIM and TWIST1; more importantly, TGFβ1 induced the expression of PLCG2, but arachidonic acid did not induce the expression of TGFB1. Finally, arachidonic acid accelerated the TGFβ1 increasing VIM and TWIST1 expressions, meanwhile arachidonic acid synthase inhibitor partially blocked the TGFβ1 increasing VIM and TWIST1 expressions. In conclusion, TGFβ1 stimulates arachidonic acid synthesis and the arachidonic acid has a function to postulate the EMT process together with TGFβ1 during mammary gland involution.
authors.affiliation: United Graduate School of Veterinarian Science, Gifu University, Gifu 501-1193, Japan.|Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
authors.forename: Haolin
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Laboratory of Animal Physiology, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China.
authors.forename: Yuning
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Laboratory of Animal Physiology, College of Biological Sciences and Technology, Beijing Forestry University, Beijing, P. R. China.
authors.forename: Ji
authors.initials: J
authors.lastname: Weng
authors.affiliation: United Graduate School of Veterinarian Science, Gifu University, Gifu 501-1193, Japan.|Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
authors.forename: Kento
authors.initials: K
authors.lastname: Usuda
authors.affiliation: United Graduate School of Veterinarian Science, Gifu University, Gifu 501-1193, Japan.|Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Fujii
authors.affiliation: United Graduate School of Veterinarian Science, Gifu University, Gifu 501-1193, Japan.|Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
authors.forename: Gen
authors.initials: G
authors.lastname: Watanabe
authors.affiliation: United Graduate School of Veterinarian Science, Gifu University, Gifu 501-1193, Japan.|Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Nagaoka
mesh_terms: D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism*; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D008321:Mammary Glands, Animal / Q000502:physiology*; D008813:Mice, Inbred ICR; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*
chemical_list: C508961:Tgfb1 protein, mouse; D053773:Transforming Growth Factor beta1; D016718:Arachidonic Acid
keywords: Arachidonic acid; Epithelial-mesenchymal transition; Involution; Mammary gland; TGFβ1