Camellia (Camellia oleifera Abel.) seed oil promotes milk fat and protein synthesis‐related gene expression in bovine mammary epithelial cells

Abstract

Camellia (Camellia oleifera Abel.) seed oil is a commonly used edible oil of China. In ancient Chinese literature, it is mentioned to be helpful for postpartum repair and lactation in women. Research on camellia seed oil (CO) as a feed additive for dairy cattle is less. We investigated the effect of CO on the expression of milk fat and protein syntheses-related genes in differentiated bovine mammary epithelial cells (MAC-T) using soybean oil (SO) as the control. The results showed that CO increased the expression of genes related to de novo synthesis of fatty acids including sterol regulatory element-binding protein 1 (SREBP1), acetyl-CoA carboxylase 1 (ACC), fatty acid synthase (FASN), lipoprotein lipase (LPL), and stearoyl-CoA desaturase (SCD) (p < .05). Among the milk protein genes analyzed, CO increased β-casein mRNA expression (p < .05) and decreased αS1-casein mRNA expression (p < .05) in MAC-T cells. CO upregulated the pathways related to milk protein synthesis with increased mRNA levels of phosphoinositide 3-kinase (PI3K), RAC-alpha serine/threonine-protein kinase (AKT1), and mammalian target of rapamycin (mTOR) (p < .05) in MAC-T cells. Ribosomal protein S6 kinase beta-1 (S6K1) gene was upregulated, and eukaryotic initiation factor 4E (eIF4E) gene (p < .05) was downregulated with CO treatment.The mRNA expression levels of janus kinase 2 (JAK2), activator of transcription 5-β (STAT5-β), and E74-like factor 5 (ELF5) were elevated in MAC-T cells treated with CO (p < .05). Meanwhile, the protein expression levels of S6K1, STAT5-β, phosphorylated mTOR (p-mTOR), p-S6K1, and p-STAT5-β increased in MAC-T cells treated with CO (p < .05). In summary, CO promoted β-casein synthesis by regulating PI3K-mTOR-S6K1 and JAK2-STAT5 signaling pathways and influenced fatty acid synthesis by regulating SREBP1-related genes in MAC-T cells. We need to further confirm the function of CO using in vivo models.

Mutation of Signal Transducer and Activator of Transcription 5 (STAT5) Binding Sites Decreases Milk Allergen αS1-Casein Content in Goat Mammary Epithelial Cells

“…Breast specific STAT5-knockout mice had impaired development of the mammary gland and the decrease of whey protein content in milk [15]. In the mammary epithelial cell lines of cows [16] and dairy goats [17], STAT5 binds to the CSN2 gene promoter and promotes the transcription and synthesis of β-casein.…”

Effects of Hydroxytyrosol against Lipopolysaccharide-Induced Inflammation and Oxidative Stress in Bovine Mammary Epithelial Cells: A Natural Therapeutic Tool for Bovine Mastitis

“…Nowadays, several natural molecules or derivates has been tested for the treatment of bovine mastitis [ 9 ]. Natural molecules are preferred thanks to their safer use for both the animal and its derivatives [ 10 , 11 , 12 ]. Interesting results have been obtained from antioxidant natural compounds such as baicalein [ 13 ], moringa extract [ 14 ] and curcumin [ 15 ].…”

miR-204-5p and miR-211 Synergistically Downregulate the αS1-Casein Content and Contribute to the Lower Allergy of Goat Milk

“…39 Camellia seed oil promotes the CSN2 transcription level, accompanied by the decrease of CSN1S1 mRNA in BMEC. 40 Our previous study revealed that the CSN1S1 gene negatively affected STAT5a activity and β-casein synthesis in GMEC. 17 Here, we performed rescue experiments to confirm whether miR-204-5p/-211 could increase STAT5a phosphorylation and β-casein expression through the CSN1S1 gene.…”