Systemic regulation of L-carnitine in nutritional metabolism in zebrafish, Danio rerio

Abstract

Excess fat accumulation has been observed widely in farmed fish; therefore, efficient lipid-lowering factors have obtained high attention in the current fish nutrition studies. Dietary L-carnitine can increase fatty acid β-oxidation in mammals, but has produced contradictory results in different fish species. To date, the mechanisms of metabolic regulation of L-carnitine in fish have not been fully determined. The present study used zebrafish to investigate the systemic regulation of nutrient metabolism by dietary L-carnitine supplementation. L-carnitine significantly decreased the lipid content in liver and muscle, accompanied by increased concentrations of total and free carnitine in tissues. Meanwhile, L-carnitine enhanced mitochondrial β-oxidation activities and the expression of carnitine palmitoyltransferase 1 mRNA significantly, whereas it depressed the mRNA expression of adipogenesis-related genes. In addition, L-carnitine caused higher glycogen deposition in the fasting state, and increased and decreased the mRNA expressions of gluconeogenesis-related and glycolysis-related genes, respectively. L-carnitine also increased the hepatic expression of mTOR in the feeding state. Taken together, dietary L-carnitine supplementation decreased lipid deposition by increasing mitochondrial fatty acid β-oxidation, and is likely to promote protein synthesis. However, the L-carnitine-enhanced lipid catabolism would cause a decrease in glucose utilization. Therefore, L-carnitine has comprehensive effects on nutrient metabolism in fish.

Provable bounds for the Korteweg–de Vries reduction in multi-component nonlinear Schrödinger equation

“…Nonetheless, we will keep our main motivation as non-equilibrium dynamics in Bose mixtures [2]. In the context of cold atoms, VNLS (aka multi-component Gross−Pitaevskii equation) appears in multiple coupled species of bosons [35][36][37][38][39][40][41][42][43][44][45][46] or bosons with hyperfine degrees of freedom (spinor BECs [47][48][49][50][51][52][53][54][55]). The nonlinearities or interactions one sees are of inter-species and intra-species type.…”

Oxidative effect of l-carnitine on energy metabolism in diploid and triploid rainbow trout (Oncorhynchus mykiss): impact on metabolites

“…The L-carnitine concentration gradient was even more pronounced between muscle and liver tissues (Ozório et al 2001). The ability to take up and retain dietary carnitine was observed in other species, such as Atlantic salmon Salmo salar L. (Ji et al 1996), red seabream Pagrus major (Chatzifotis and Takeuchi 1997), rabbits (Bell et al 1992), piglets (Böhles et al 1984), rats (Tsai et al 1974), among other species (Li et al 2017).…”

“…The comparative results between diploid and triploid fish are often contradictory (Ihssen et al 1990;Galbreath et al 1994;Li et al 2017). The general consensus is that the survival and growth are substantially lower in the early life stages in triploids compared to diploids (Thorgaard 1986;Sutterlin et al 1987;Malison et al 1993;Withler et al 1995).…”

Surface reconstruction and charge modulation in BaFe2As2 superconducting film

“…For doped superconductors such as BFCA, effective annealing yields increased TC and critical current density (JC). 39,40 As a result, it is understood that inhomogeneity of the Co doping level occurs at nanometer scale. Figure 4 shows the change in resistance with temperature.…”

“…5b, in the outer region covered by Ba atoms, the tunneling spectrum exhibits a V-shaped gap feature, which is similar to previous results for the cleaved surface. 32,39 On the other hand, the tunneling spectrum in region "B" shows a more pronounced superconducting gap feature with ∆ ≈ 6 meV and clearer coherence peaks than those in the Bacovered region. This result clearly implies that the electronic state of the surface Ba atoms screens the superconducting property of the As-Fe-As trilayer to the STM tunnel junction.…”