1. Regulation of LCPUFA biosynthesis
To elucidate the basic biochemical pathways of fatty acid
synthesis in animals and humans as well as exploring the role
of individual LCPUFA in regulating cell function.
A series of experiments designed to unravel the effects of
dietary PUFA consumption on the endogenous synthesis of DHA
from ALA have been conducted in rats. The results demonstrated
the sensitivity of DHA accumulation to dietary PUFA content,
presumably because of inhibition of the 6 desaturase. These
studies will be extended to test whether DHA accumulation
was chiefly regulated via PUFA inhibition of DHA synthesis
or through PUFA inhibiting DHA incorporation into membrane
phospholipids.
To address the effect of PUFA on DHA biosynthesis we have
also initiated studies using the human HepG2 cell line. RT-PCR
studies have established that although ALA inhibits the 6
desaturase, the limiting step in the conversion of ALA to
DHA, the effect is not specific and all unsaturated fatty
acids also act in this way. Further studies are underway to
assess the effect of PUFA on incorporation of DHA into membrane
phospholipids.
Wei-Chun Tu in the Fatty acids
laboratory
|
