A krill oil supplemented diet reduces the activities of the mitochondrial tricarboxylate carrier and of the cytosolic lipogenic enzymes in rats

Abstract

The mitochondrial tricarboxylate carrier supplies cytosol with the carbon units necessary for hepatic lipogenesis. The activities of cytosolic acetyl-CoA carboxylase and fatty acid synthetase are therefore strictly connected to the function of mitochondrial tricarboxylate carrier. Dietary polyunsaturated fatty acids (PUFA) are potent modulators of hepatic lipogenesis. In rats fed with a diet enriched with 2.5% krill oil (KO), a novel source of dietary n-3 PUFA, a time-dependent decrease in the activities of the mitochondrial tricarboxylate carrier and of the lipogenic enzymes was found. The KO induced inhibition of hepatic lipogenesis was more pronounced than that found in fish oil (FO)-fed rats, at least at short feeding times. The decrease in the activity of the mitochondrial tricarboxylate carrier caused by KO was due to a reduced expression of the protein. Furthermore, in the KO-fed animals a greater reduction in the levels of hepatic triglycerides and cholesterol was found in comparison to FO-fed rats.

Effect of dietary eicosapentaenoic and docosahexaenoic acid on expression of rat liver genes controlling cholesterol homeostasis and on plasma cholesterol level

“…Similarly to the present study (Figure 2), FO in the rat diet decreased plasma TC also in most of the recent studies (Lu et al 2011;Takahashi 2011;Campioli et al 2012;Ferramosca et al 2012;Xiao et al 2012). However, Yamazaki et al (2011) and Campioli et al (2012) did not find differences in TC between the FO-fed rats and the control rats.…”

“…Plasma cholesterol. Plasma TC level of the FOfed rats in the present experiment (1.07 mmol/l; Figure 2) is approximately in the middle of the range of the results of similar experiments (FO-fed rats; all data recalculated to mmol/l): 3.22 (Lu et al 2011) → 2.45 (Ferramosca et al 2012) → 2.36 (Xiao et al 2012) → 2.04 (Campioli et al 2012) → 1.01 (Yamazaki et al 2011) → 0.98 (Takahashi 2011) → 0.54 (Popovic et al 2011).…”

“…Published data regarding HDL-C also vary conspicuously between 1.11 mmol/l (Ferramosca et al 2012) and 0.17 mmol/l (Popovic et al 2011), with the level found in the present experiment (0.35 mmol/l) approximately in the middle.…”

“…Fish oil (FO) in the rat diet decreased plasma TC in most of the recent studies (Lu et al 2011;Ferramosca et al 2012;Xiao et al 2012). On the other hand, regarding studies in humans, EPA/DHA either reduced TC and LDL-C (Lopez-Huertas 2009) or increased both TC and LDL-C and HDL-C (Maki et al 2003) or no change in TC and slight increases in HDL-C and LDL-C, respectively were established (Eslick et al 2009).…”

Phospholipids from herring roe improve plasma lipids and glucose tolerance in healthy, young adults

“…A recent study comparing the bioavailability of PL and TAG in the form of krill oil and fish oil in healthy subjects demonstrated increased levels of EPA and DHA in plasma and red blood cells (RBC) after four weeks of krill oil intake compared to fish oil [8]. In addition, animal studies have shown a more efficient reduction in plasma lipid levels with PL compared to TAG intervention [9]. Herring roe oil supplementation has shown promising results in animal studies, including reduction in plasma lipids and inflammatory parameters, and improved insulin sensitivity [10,11].…”