Chemerin Regulates Epithelial Barrier Function of Mammary Glands in Dairy Cows

Abstract

Epithelial barrier function in the mammary gland acts as a forefront of the defense mechanism against mastitis, which is widespread and a major disorder in dairy production. Chemerin is a chemoattractant protein with potent antimicrobial ability, but its role in the mammary gland remains unelucidated. The aim of this study was to determine the function of chemerin in mammary epithelial tissue of dairy cows in lactation or dry-off periods. Mammary epithelial cells produced chemerin protein, and secreted chemerin was detected in milk samples. Chemerin treatment promoted the proliferation of cultured bovine mammary epithelial cells and protected the integrity of the epithelial cell layer from hydrogen peroxide (H2O2)-induced damage. Meanwhile, chemerin levels were higher in mammary tissue with mastitis. Tumor necrosis factor alpha (TNF-α) strongly upregulated the expression of the chemerin-coding gene (RARRES2) in mammary epithelial cells. Therefore, chemerin was suggested to support mammary epithelial cell growth and epithelial barrier function and to be regulated by inflammatory stimuli. Our results may indicate chemerin as a novel therapeutic target for diseases in the bovine mammary gland.

Chemerin Stimulates the Secretory Activity of BME-UV1 Bovine Mammary Epithelial Cells

“…The treatment of MAC-T cells with chemerin caused an increased expression of genes involved in milk protein synthesis, glucose uptake, and fatty acid synthesis, suggesting that chemerin may regulate the process of milk synthesis in the bovine mammary gland [18]. In another study, Suzuki et al [19] demonstrated that chemerin supports bovine MEC growth and epithelial barrier function and is strongly regulated by inflammatory stimuli, such as TNFα.…”

“…Studies conducted in recent years revealed that chemerin may be one of the essential adipokines regulating the development and function of the mammary epithelium [18,19]. Chemerin, also known as retinoic acid receptor responder protein 2 (RARRES2), or tazaroteneinduced gene 2 protein (TIG2), is a 16 kDa chemoattractant cytokine (chemokine) secreted mainly by white adipose tissue [20].…”

Adipocyte-Derived Paracrine Factors Regulate the In Vitro Development of Bovine Mammary Epithelial Cells

“…The mammary gland adipose tissue provides a local source of fatty acids and metabolites for MEC [13]. The indirect regulation of the mammary epithelium by adipocytes is connected with their high secretory activity and local production of adipokines, such as leptin, adiponectin, chemerin, vascular endothelial growth factor (VEGF), interleukin 6 (IL-6), or tumor necrosis factor alpha (TNF-α) [13][14][15][16][17]. Deficiency in leptin signaling caused by loss of function mutation in the leptin gene causes defective mammary development.…”

Effects of Serotonin on Cell Viability, Permeability of Bovine Mammary Gland Epithelial Cells and Their Transcriptome Analysis

“…In addition, the MAC-T is one of the most often used immortalized bovine mammary epithelial cell lines to study bovine mammary gland functions, such as cell proliferation and apoptosis, tight junction permeability, inflammations, etc. [20][21][22][23]. Therefore, the objective of the current study was to investigate the effects of 5-HT on global gene expression profiles of bovine mammary epithelial cells by applying transcriptome analysis in MAC-T cells.…”