Optimizing hormonal and amino acid combinations for enhanced cell proliferation and cell cycle progression in bovine mammary epithelial cells

• Published in: Animal Bioscience Vol. 36; no. 11; pp. 1757 - 1768
• Main Authors: Kwon, Hyuk Cheol, Jung, Hyun Su, Kim, Do Hyun, Han, Jong Hyeon, Han, Seo Gu, Keum, Dong Hyun, Hong, Seong Joon, Han, Sung Gu
• Format: Journal Article
• Language: English
• Published: Asian - Australasian Association of Animal Production Societies 01.11.2023; Animal Bioscience; Asian-Australasian Association of Animal Production Societies; 아세아·태평양축산학회
• Subjects: Amino acids; bovine mammary epithelial cell; Cattle; Cell cycle; Cell proliferation; Corticosteroids; Dairy cattle; Epidermal growth factor; Epithelial cells; essential amino acid; Estradiol; Ethylenediaminetetraacetic acid; Health aspects; hormone; Hormones; Mammary glands; Milk; Milk production; optimization; Progesterone; 축산학; South Korea
• ISSN: 2765-0189; 2765-0235
• DOI: 10.5713/ab.23.0199

Objective: The number of bovine mammary epithelial cells (BMECs) is closely associated with the quantity of milk production in dairy cows; however, the optimal levels and the combined effects of hormones and essential amino acids (EAAs) on cell proliferation are not completely understood. Thus, the purpose of this study was to determine the optimal combination of individual hormones and EAAs for cell proliferation and related signaling pathways in BMECs.Methods: Immortalized BMECs (MAC-T) were treated with six hormones (insulin, cortisol, progesterone, estrone, 17β-estradiol, and epidermal growth factor) and ten EAAs (arginine, histidine, leucine, isoleucine, threonine, tryptophan, lysine, methionine, phenylalanine, and valine) for 24 h.Results: Cells were cultured in a medium containing 10% fetal bovine serum (FBS) as FBS supplemented at a concentration of 10% to 50% showed a comparable increase in cell proliferation rate. The optimized combination of four hormones (insulin, cortisol, progesterone, and 17β-estradiol) and 20% of a mixture of ten EAAs led to the highest cell proliferation rate, which led to a significant increase in cell cycle progression at the S and G2/M phases, in the protein levels of proliferating cell nuclear antigen and cyclin B1, cell nucleus staining, and in cell numbers.Conclusion: The optimal combination of hormones and EAAs increased BMEC proliferation by enhancing cell cycle progression in the S and G/2M phases. Our findings indicate that optimizing hormone and amino acid levels has the potential to enhance milk production, both in cell culture settings by promoting increased cell numbers, and in dairy cows by regulating feed intake.