Effects of waterborne copper exposure on carnitine composition, kinetics of carnitine palmitoyltransferases I (CPT I) and mRNA levels of CPT I isoforms in yellow catfish Pelteobagrus fulvidraco

Chemosphere ◽  
2015 ◽  
Vol 139 ◽  
pp. 349-357 ◽  
Author(s):  
Qi-Liang Chen ◽  
Zhi Luo ◽  
Cai-Xia Liu ◽  
Jia-Lang Zheng ◽  
Qing-Ling Zhu ◽  
...  
2017 ◽  
Vol 118 (8) ◽  
pp. 570-579 ◽  
Author(s):  
Guang-Hui Chen ◽  
Christer Hogstrand ◽  
Zhi Luo ◽  
Dian-Guang Zhang ◽  
Shi-Cheng Ling ◽  
...  

AbstractThe present study explored the mechanisms of dietary Zn influencing Zn and lipid deposition in the fore- and mid- intestine in yellow catfishPelteobagrus fulvidraco, and investigated whether the mechanism was intestinal-region dependent. For this purpose, yellow catfish were fed three diets containing Zn levels of 8·83, 19·20 and 146·65 mg Zn/kg, respectively. Growth performance, intestinal TAG and Zn contents as well as activities and mRNA expression of enzymes and genes involved in Zn transport and lipid metabolism in the fore- and mid-intestine were analysed. Dietary Zn increased Zn accumulation as well as activities of Cu-, Zn-superoxide dismutase and ATPase in the fore- and mid-intestine. In the fore-intestine, dietary Zn up-regulated mRNA levels of ZnT1, ZnT5, ZnT7, metallothionein (MT) and metal response element-binding transcription factor-1 (MTF-1), but down-regulated mRNA levels of ZIP4 and ZIP5. In the mid-intestine, dietary Zn up-regulated mRNA levels of ZnT1, ZnT5, ZnT7, MT and MTF-1, but down-regulated mRNA levels of ZIP4 and ZIP5. Dietary Zn reduced TAG content, down-regulated activities of 6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME) and fatty acid synthase (FAS) activities, and reduced mRNA levels of 6PGD, G6PD, FAS, PPARγand sterol-regulator element-binding protein (SREBP-1), but up-regulated mRNA levels of carnitine palmitoyltransferase IA, hormone-sensitive lipase (HSLa), adipose TAG lipase (ATGL) and PPARαin the fore-intestine. In the mid-intestine, dietary Zn reduced TAG content, activities of G6PD, ME, isocitrate dehydrogenase and FAS, down-regulated mRNA levels of 6PGD, G6PD, FAS, acetyl-CoA carboxylase a, PPARγand SREBP-1, but up-regulated mRNA expression of HSLa, ATGL and PPARγ. The reduction in TAG content following Zn addition was attributable to reduced lipogenesis and increased lipolysis, and similar regulatory mechanisms were observed between the fore- and mid-intestine.


Genes ◽  
2019 ◽  
Vol 10 (10) ◽  
pp. 751 ◽  
Author(s):  
Wu ◽  
Wei ◽  
Yang ◽  
Zhao ◽  
Luo

The autophagy-lysosome pathway, which involves many crucial genes and proteins, plays crucial roles in the maintenance of intracellular homeostasis by the degradation of damaged components. At present, some of these genes and proteins have been identified but their specific functions are largely unknown. This study was performed to clone and characterize the full-length cDNA sequences of nine key autolysosome-related genes (vps11, vps16, vps18, vps33b, vps41, lamp1, mcoln1, ctsd1 and tfeb) from yellow catfish Pelteobagrus fulvidraco. The expression of these genes and the transcriptional responses to a high-fat diet and fatty acids (FAs) (palmitic acid (PA) and oleic acid (OA)) were investigated. The mRNAs of these genes could be detected in heart, liver, muscle, spleen, brain, mesenteric adipose tissue, intestine, kidney and ovary, but varied with the tissues. In the liver, the mRNA levels of the nine autolysosome-related genes were lower in fish fed a high-fat diet than those fed the control, indicating that a high-fat diet inhibited formation of autolysosomes. Palmitic acid (a saturated FA) significantly inhibited the formation of autolysosomes at 12 h, 24 h and 48 h incubation. In contrast, oleic acid (an unsaturated FA) significantly induced the formation of autolysosomes at 12 h, but inhibited them at 24 h. At 48 h, the effects of OA incubation on autolysosomes were OA concentration-dependent in primary hepatocytes of P. fulvidraco. The results of flow cytometry and laser confocal observations confirmed these results. PA and OA incubation also increased intracellular non-esterified fatty acid (NEFA) concentration at 12 h, 24 h and 48 h, and influenced mRNA levels of fatty acid binding protein (fabp) and fatty acid transport protein 4 (fatp4) which facilitate FA transport in primary hepatocytes of P. fulvidraco. The present study demonstrated the molecular characterization of the nine autolysosome-related genes and their transcriptional responses to fat and FAs in fish, which provides the basis for further exploring their regulatory mechanism in vertebrates.


1995 ◽  
Vol 306 (2) ◽  
pp. 379-384 ◽  
Author(s):  
G Asins ◽  
D Serra ◽  
G Arias ◽  
F G Hegardt

Carnitine palmitoyltransferase (CPT) I is expressed in the intestine of suckling rats; its mRNA increases very rapidly after birth, remains on a plateau until day 18 and decreases until weaning, when basal (adult) values are reached, which remain unchanged thereafter. CPT II mRNA values do not show any appreciable change in this period. CPT I and CPT II are expressed mainly in mucosa and, to a lesser extent, in the muscular part of the intestine. Intestinal expression of CPT I is maximal in duodenum and jejunum, whereas CPT II is expressed in a similar pattern throughout the whole intestine. Dam's milk may influence the intestinal expression of CPT I, since mRNA levels at birth are low but increase after the first lactation. Moreover, rats weaned at either day 18 or 21 decrease their mRNA levels. Apparently, CPT II gene expression is not influenced by the mother's milk. CPT I and CPT II are also expressed in the liver of suckling rats. Hepatic CPT I is maximal at day 3, and levels of CPT II mRNA do not change, in a similar fashion to that in intestine. The profile of expression of CPT I in liver and intestine strongly resembles that previously reported for mitochondrial 3-hydroxy-3-methyl-glutaryl-CoA synthase.


Antioxidants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 535
Author(s):  
Dian-Guang Zhang ◽  
Tao Zhao ◽  
Xiao-Jian Xu ◽  
Wu-Hong Lv ◽  
Zhi Luo

Selenium (Se) is an essential micro-mineral and plays important roles in antioxidant responses, and also influences lipid metabolism and selenoprotein expression in vertebrates, but the effects and mechanism remain unknown. The study was undertaken to decipher the insights into dietary Se influencing lipid metabolism and selenoprotein expression in the anterior and middle intestine (AI and MI) of yellow catfish Pelteobagrus fulvidraco. Yellow catfish (weight: 8.27 ± 0.03 g) were fed a 0.03- (M-Se), 0.25- (A-Se), or 6.39- (E-Se) mg Se/kg diet for 12 wk. AI and MI were analyzed for triglycerides (TGs) and Se concentrations, histochemistry and immunofluorescence, enzyme activities, and gene and protein levelsassociated with antioxidant responses, lipid metabolism, endoplasmic reticulum (ER) stress, and selenoproteome. Compared to the A-Se group, M-Se and E-Se diets significantly decreased weight gain (WG) and increased TGs concentration in the AI and MI. In the AI, compared with A-Se group, M-Se and E-Se diets significantly increased activities of fatty acid synthase, expression of lipogenic genes, and suppressed lipolysis. In the MI, compared to the A-Se group, M-Se and E-Se diets significantly increased activities of lipogenesis and expression of lipogenic genes. Compared with A-Se group, E-Se diet significantly increased glutathione peroxidase (GPX) activities in the AI and MI, and M-Se diet did not significantly reduce GPX activities in the AI and MI. Compared with the A- Se group, E-Se diet significantly increased glutathione peroxidase (GPX) activities in the plasma and liver, and M-Se diet significantly reduced GPX activities in the plasma and liver. Compared with the A-Se group, M-Se and E-Se groups also increased glucose-regulated protein 78 (GRP78, ER stress marker) protein expression of the intestine. Dietary Se supplementation also differentially influenced the expression of the 28 selenoproteins in the AI and MI, many of which possessed antioxidant characteristics. Compared with the A-Se group, the M-Se group significantly decreased mRNA levels of txnrd2 and txnrd3, but made no difference on mRNA levels of these seven GPX proteins in the MI. Moreover, we characterized sterol regulatory element binding protein 1c (SREBP1c) binding sites of three ER-resident proteins (selenom, selenon, and selenos) promoters, and found that Se positively controlled selenom, selenon, and selenos expression via SREBP1c binding to the selenom, selenon, and selenos promoter. Thus, dietary marginal and excess Se increased TGs deposition of yellow catfish P. fulvidraco, which might be mediated by ER-resident selenoproteins expression and ER stress.


2014 ◽  
Vol 112 (5) ◽  
pp. 698-708 ◽  
Author(s):  
Jia-Lang Zheng ◽  
Zhi Luo ◽  
Mei-Qing Zhuo ◽  
Ya-Xiong Pan ◽  
Yu-Feng Song ◽  
...  

Carnitine has been reported to improve growth performance and reduce body lipid content in fish. Thus, we hypothesised that carnitine supplementation can improve growth performance and reduce lipid content in the liver and muscle of yellow catfish (Pelteobagrus fulvidraco), a commonly cultured freshwater fish in inland China, and tested this hypothesis in the present study. Diets containing l-carnitine at three different concentrations of 47 mg/kg (control, without extra carnitine addition), 331 mg/kg (low carnitine) and 3495 mg/kg (high carnitine) diet were fed to yellow catfish for 8 weeks. The low-carnitine diet significantly improved weight gain (WG) and reduced the feed conversion ratio (FCR). In contrast, the high-carnitine diet did not affect WG and FCR. Compared with the control diet, the low-carnitine and high-carnitine diets increased lipid and carnitine contents in the liver and muscle. The increased lipid content in the liver could be attributed to the up-regulation of the mRNA levels of SREBP, PPARγ, fatty acid synthase (FAS) and ACCa and the increased activities of lipogenic enzymes (such as FAS, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and malic enzyme) and to the down-regulation of the mRNA levels of the lipolytic gene CPT1A. The increased lipid content in muscle could be attributed to the down-regulation of the mRNA levels of the lipolytic genes CPT1A and ATGL and the increased activity of lipoprotein lipase. In conclusion, in contrast to our hypothesis, dietary carnitine supplementation increased body lipid content in yellow catfish.


2020 ◽  
Vol 21 (5) ◽  
pp. 1615 ◽  
Author(s):  
Shi-Cheng Ling ◽  
Mei-Qin Zhuo ◽  
Dian-Guang Zhang ◽  
Heng-Yang Cui ◽  
Zhi Luo

The present study was conducted to explore the mechanism of nano-Zn absorption and its influence on lipid metabolism in the intestine of yellow catfish Pelteobagrus fulvidraco. Compared to ZnSO4, dietary nano-Zn addition increased the triglyceride (TG) content, enzymatic activities of malic enzyme (ME) and fatty acid synthase (FAS), and up-regulated mRNA levels of 6pgd, fas, acca, dgat1, pparγ, and fatp4. Using primary intestinal epithelial cells of yellow catfish, compared to the ZnSO4 group, nano-Zn incubation increased the contents of TG and free fatty acids (FFA), the activities of glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6GPD), ME, and FAS, up-regulated mRNA levels of lipogenic genes (6pgd, g6pd, fas, dgat1, and pparγ), genes of lipid transport (fatp4 and ifabp), and Zn transport genes (znt5, znt7, mt, and mtf1), and increased the protein expression of fatty acid transport protein 4 (FATP4) and peroxisome proliferator activated receptor gamma (PPARγ). Further studies found that nano-Zn absorption was via the clathrin-dependent endocytic mechanism. PPARγ mediated the nano-Zn-induced increase in TG, and nano-Zn increased Zn accumulation and induced TG accumulation by activating the PPARγ pathway and up-regulating lipogenesis.


Sign in / Sign up

Export Citation Format

Share Document