Abstract
Simple SummaryIn non-ruminant liver and adipose tissue, cAMP response element binding protein 1(CREB1) is essential for lipid synthesis and triacylglycerol accumulation. The present study aimed to ascertain the role of CREB1 in regulating milk fatty acid composition synthesized by goat mammary gland. Our data found that overexpression of CREB1 in vitro alters the abundance of lipogenic genes, triacylglycerol accumulation and concentration of monounsaturated fatty acids in goat mammary epithelial cells. Thus, manipulation of CREB1 in vivo might be one approach to improve the quality of goat milk.cAMP response element binding protein 1 (CREB1) is a member of the leucine zipper transcription factor family of DNA binding proteins. Although studies in non-ruminants have demonstrated a crucial role of CREB1 in lipid synthesis in liver and adipose tissue, it is unknown if this transcription regulator exerts control of fatty acid synthesis in ruminant mammary cells. To address this question, we first defined the expression dynamics of CREB1 in mammary tissue during lactation. Analysis of CREB1 in mammary tissue revealed higher mRNA abundance in mammary tissue harvested at peak lactation. Overexpression of CREB1 markedly upregulated sterol regulatory element binding transcription factor 1 (SREBP1), fatty acid synthase (FASN), acetyl-coenzyme A carboxylase α (ACACA), elongase of very long chain fatty acids 6 (ELOVL6), lipoprotein lipase (LPL), fatty acid binding protein 3 (FABP3), lipin 1 (LPIN1) and diacylglycerol acyltransferase 1 (DGAT1), but had no effect on glycerol-3-phosphate acyltransferase, mitochondrial (GPAM) or 1-acylglycerol-3-phosphate O-acyltransferase 6 (AGPAT6). In addition, overexpressing CREB1 led to a significant increase in the concentration and desaturation index of C16:1 (palmitoleic acid) and C18:1 (oleic acid), along with increased concentration of triacylglycerol. Taken together, these results highlight an important role of CREB1 in regulating lipid synthesis in goat mammary epithelial cells. Thus, manipulation of CREB1 in vivo might be one approach to improve the quality of goat milk.
Highlights
Compared with cow milk, goat milk contains a much greater proportion of monounsaturated fatty acids (MUFA) which enhance nutritional value in terms of human health including benefits for control of cardiovascular conditions and hypercholesterolemia or hyperlipemia [1]
In order to further investigate the effect of cAMP response element binding protein 1 (CREB1) on fatty acid synthesis in goat mammary epithelial cells (GMEC), the relative content of fatty acid was measured
The present study provided direct evidence that overexpression of CREB1 enhances de novo fatty acid synthesis and lipid accumulation in GMEC, some limitations of the study need to be considered
Summary
Goat milk contains a much greater proportion of monounsaturated fatty acids (MUFA) which enhance nutritional value in terms of human health including benefits for control of cardiovascular conditions and hypercholesterolemia or hyperlipemia [1]. More powerful evidence for CREB in the control of TAG metabolism was obtained via CREB knockdown with specific antisense oligonucleotides Results revealed that it decreased TAG concentrations in mouse liver, and affected the expression of several genes involved in synthesis of fatty acids (FA) and TAG, including acetyl-coenzyme A carboxylase alpha 1 (ACACA1), SCD1 and diacylglycerol acytransferase 2 (DGAT1) [14]. We used fatty acid analysis to determine to which extent CREB1 could alter the content of monounsaturated fatty acids known to originate from de novo synthesis
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
