| Accumulation of lipid droplets in the hepatocytes during the perinatal period leads
to fatty liver in dairy cows.
Phosphocholine cytidylyltransferase alpha (CCT -α) is an important rate limiting enzyme in CDP’s choline
pathway,and its role in regulating lipid accumulation is unclear in bovine hepatocytes.In this experiment,CCT -α
knockout (CCT-KO) and overexpressed (CCT-OE) hepatocyte lines of bovine were studied, and oil red staining was
used to detect the size and quantity of lipid droplets (LDs) in cells.The content of phosphatidylcholine (PC) was
analyzed by TLC and the expression of autophagy protein was detected by Western blot.The results showed that the
diameter of LDs in bovine hepatocytes of the control group was 1.51 μm,the diameter of LDs in the CCT- KO group
was increased to 2.29 μm,and the diameter in the CCT -OE group was decreased to 1.27 μm.CCT -α gene knockout
significantly reduced the number of lipid droplets,while CCT -α gene overexpression significantly increased the number of
lipid droplets (P<0.05).The content of phosphatidylcholine (PC) in CCT KO group was decreased,while that of
CCTOE
group was significantly increased.Compared with control group,the ratio of C3 Ⅱ/
LC3 Ⅰ protein in CCT KO
group was decreased by 18.9% and p62 protein was up regulated by 19.1%,while the ratio of LC3-Ⅱ/LC3 Ⅰ was increased
by 35.7%,and the expression of p62 protein was down regulated by 31.3% in CCT OE group.These results indicate that the
CCT α gene regulates LD size by influencing the synthesis of cytophospholipids and autophagy,which lays a foundation for
illustrating the mechanism of fatty liver in dairy cows. |