Induction of Peroxisomal .BETA.-Oxidation and Fatty Acid Content in Primary Cultures of Rat Hepatocytes.

Triglyceride Accumulation by Peroxisome Proliferators in Rat Hepatocytes

“…Fatty acid transporter up-regulation by PxPs 15) increases the influx of fatty acids to hepatocyes. 16) Though TG is normally synthesized utilizing the transported fatty acids, TG is accumulated in hepatocytes due to the inhibition of VLDL secretion by PxPs, which is consistent with the report of Schoonjans et al, 6) leading to a lowering TG in the medium. Together with the results of recent studies on the regulation of membrane efflux transporters in the ABC family by PxPs, such as ABCA1 in intestines by Wy 14,643 47) and multidrug resistance-associated proteins in the liver by clofibrate, 48) it is hypothesized that hepatocellular membrane molecules or structures related to VLDL secretion might be modified by PxPs.…”

“…Since long chain fatty acids are accumulated in rat hepatocytes following treatment with PxPs, 16) hepatic DGAT activity that catalyzes the final reaction in TG synthesis was examined. A previous study showed that fibrates raised overt (cytosol-facing) DGAT activity and inhibited latent (endoplasmic reticulum lumen-facing) DGAT activity, 40) thus even if the apparent activity was not affected by Nf treatment using microsomal fractions, as the enzyme source, we considered that the results on DGAT (Fig.…”

“…On the other hand, fibrates induce fatty acid transporter protein in rat livers, 15) by which hepatic uptake of fatty acids is enhanced. A linear increasing correlation between Px-ox activity and cellular long chain fatty acid level by PxP was reported in rat cultured hepatocytes, 16) leading to hepatic TG accumulation when the TG synthesis process was completed, as well as a fibrate and a long chain fatty acid enhanced cellular TG level with a increase in Px-ox activity. 17) In in vivo experiments, PxPs including fatty acid analogues enhanced hepatic TG accumulation, 11,18,19) or in contrast, decrease it, [20][21][22] when the increase in Px-ox activity and the decrease in plasma TG were simultaneously observed.…”

Erucic Acid—Both Sides of the Story: A Concise Review on Its Beneficial and Toxic Properties

“…Interestingly, a lower dose of EA (0.1 mM) revealed no effect on the activity of peroxisomal β-oxidation, carnitine acetyltransferase, or palmitoyltransferase [ 17 ]. Similarly, the compound not only increased β-oxidation activity in rat hepatocytes but was also cytotoxic to the cells, causing higher LDH leakage than in the untreated control cells [ 18 ]. On the contrary, no toxicity of EA to rat hepatoma Fao cells was observed, which may result from high peroxisomal activity in these cells [ 19 ].…”