scholarly journals Hepatic Overexpression of Hormone-sensitive Lipase and Adipose Triglyceride Lipase Promotes Fatty Acid Oxidation, Stimulates Direct Release of Free Fatty Acids, and Ameliorates Steatosis

2008 ◽  
Vol 283 (19) ◽  
pp. 13087-13099 ◽  
Author(s):  
Brendan N. Reid ◽  
Gene P. Ables ◽  
Oleg A. Otlivanchik ◽  
Gabriele Schoiswohl ◽  
Rudolf Zechner ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Oxidation ◽  
Hormone Sensitive Lipase ◽  
Acid Oxidation ◽  
Adipose Triglyceride Lipase ◽  
Triglyceride Lipase ◽  
Hormone Sensitive

scholarly journals EFFECTS OF CORTISOL ON CULTURED RAT HEART CELLS

1973 ◽  
Vol 57 (1) ◽  
pp. 109-116 ◽  
Author(s):  
J. V. Anastasia ◽  
R. L. McCarl
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Oxidation ◽  
Growth Medium ◽  
Rat Heart ◽  
Acid Oxidation ◽  
Heart Cells ◽  
Atp Production ◽  
Rat Heart Cells

This paper reports the determination of the ability of rat heart cells in culture to release [14C]palmitate from its triglyceride and to oxidize this fatty acid and free [14C]palmitate to 14CO2 when the cells are actively beating and when they stop beating after aging in culture. In addition, the levels of glucose, glycogen, and ATP were determined to relate the concentration of these metabolites with beating and with cessation of beating. When young rat heart cells in culture are actively beating, they oxidize free fatty acids at a rate parallel with cellular ATP production. Both fatty acid oxidation and ATP production remain constant while the cells continue to beat. Furthermore, glucose is removed from the growth medium by the cells and stored as glycogen. When cultured cells stop beating, a decrease is seen in their ability to oxidize free fatty acids and to release them from their corresponding triglycerides. Concomitant with decreased fatty acid oxidation is a decrease in cellular levels of ATP until beating ceases. Midway between initiation of cultures and cessation of beating the cells begin to mobilize the stored glycogen. When the growth medium is supplemented with cortisol acetate and given to cultures which have ceased to beat, reinitiation of beating occurs. Furthermore, all decreases previously observed in ATP levels, fatty acid oxidation, and esterase activity are restored.

Lipid and glycogen metabolism in the hypoxic heart: effects of epinephrine

1975 ◽  
Vol 229 (4) ◽  
pp. 885-889 ◽  
Author(s):  
Crass MF ◽  
GM Pieper
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Oxidation ◽  
Glycogen Metabolism ◽  
Acid Oxidation ◽  
Triglyceride Fatty Acid ◽  
Rat Hearts ◽  
Perfused Rat Hearts

The metabolism of cardiac lipids and glycogen in hypoxic and well-oxygenated perfused rat hearts was studied in the presence or absence of epinephrine. Heart lipids were pre-labeled in vivo with [1-14C]palmitate. Triglyceride disappearance (measured chemically and radiochemically) was observed in well-oxygenated hearts and was stimulated by epinephrine (4.1 X 10(-7)M). Utilization of tissue triglycerides was inhibited in hypoxic hearts in the presence or absence of added epinephrine. Hypoxia resulted in a small increase in tissue 14C-free fatty acids and inhibition of 14C-labeled triglyceride fatty acid oxidation. Epinephrine had no stimulatory effect on fatty acid oxidation in hypoxic hearts. Utilization of 14C-labeled phospholipids (and total phospholipids) was similar in well-oxygenated and hypoxic hearts with or without added epinephrine. These results suggested that the antilipolytic effects of hypoxia were predominant over the lipolytic effects of epinephrine. Glycogenolysis was stimulated threefold by epinephrine in well-oxygenated hearts. Hypoxia alone was a potent stimulus to glycogenolysis. Addition of epinephrine to perfusates of hypoxic hearts resulted in a slight enhancement of glycogenolysis.

Novel regulatory roles of carboxylesterase 3 in lipid metabolism and browning in 3T3-L1 white adipocytes

2019 ◽  
Vol 44 (10) ◽  
pp. 1089-1098 ◽  
Author(s):  
Sulagna Mukherjee ◽  
Minji Choi ◽  
Jong Won Yun
Keyword(s):  
Lipid Metabolism ◽  
Cell Model ◽  
Hormone Sensitive Lipase ◽  
Marker Genes ◽  
Acid Oxidation ◽  
Adipose Triglyceride Lipase ◽  
Triglyceride Lipase ◽  
White Adipocytes ◽  
Enhanced Expression ◽  
Hormone Sensitive

The role of carboxylesterase 3 (Ces3) in the lipolysis of adipocytes has been overlooked, as 2 major lipolytic enzymes, hormone-sensitive lipase and adipose triglyceride lipase, play more powerful roles in lipolysis. In this study, we explored the effects of Ces3 in lipid metabolism by activating and inhibiting, as well as silencing, Ces3-encoding gene in 3T3-L1 cell model. Our results demonstrated that activation of Ces3 increased adipogenesis, and attenuated lipogenesis, whereas it promoted lipolysis and fatty acid oxidation. In addition, activated Ces3 led to enhanced expression of core fat browning marker genes and proteins, suggesting that Ces3 may play a pivotal role in fat browning and thermogenesis. In contrast, deficiency of Ces3 nullified the browning effect in white adipocytes, along with decreased adipogenesis in 3T3-L1 adipocytes. Interestingly, the expression pattern of adipose triglyceride lipase was in line with Ces3, whereas hormone-sensitive lipase was independently regulated irrespective of Ces3 expression levels, suggesting that Ces3 may play an important and compensatory role in the breakdown of triglycerides in white adipocytes. In conclusion, we provide the first evidence that activation of Ces3 contributes in the browning of white adipocytes, and maintains a balance in lipid metabolism, which could be a potential strategy in fighting against obesity.

Plasma free fatty acids in mitochondrial fatty acid oxidation defects

1997 ◽  
Vol 267 (2) ◽  
pp. 143-154 ◽  
Author(s):  
G Martı́nez ◽  
G Jiménez-Sánchez ◽  
P Divry ◽  
C Vianey-Saban ◽  
E Riudor ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Oxidation ◽  
Acid Oxidation ◽  
Mitochondrial Fatty Acid Oxidation ◽  
Plasma Free Fatty Acids ◽  
Mitochondrial Fatty Acid

Fasting upregulates adipose triglyceride lipase and hormone-sensitive lipase levels and phosphorylation in mouse kidney

2015 ◽  
Vol 93 (3) ◽  
pp. 262-267 ◽  
Author(s):  
Phillip M. Marvyn ◽  
Ryan M. Bradley ◽  
Emily B. Button ◽  
Emily B. Mardian ◽  
Robin E. Duncan
Keyword(s):  
Fatty Acids ◽  
Hormone Sensitive Lipase ◽  
Binding Motif ◽  
Adipose Triglyceride Lipase ◽  
Triglyceride Lipase ◽  
Protein Levels ◽  
Fasted State ◽  
Esterified Fatty Acids ◽  
Glomerular Filtrate ◽  
Hormone Sensitive

Circulating non-esterified fatty acids (NEFA) rise during fasting and are taken up by the kidneys, either directly from the plasma or during re-uptake of albumin from glomerular filtrate, and are stored as triacylglycerol (TAG). Subsequent utilization of stored fatty acids requires their hydrolytic release from cellular lipid droplets, but relatively little is known about renal lipolysis. We found that total [3H]triolein hydrolase activity of kidney lysates was significantly increased by 15% in the fasted state. Adipose triglyceride lipase (Atgl) and hormone-sensitive lipase (Hsl) mRNA expression was time-dependently increased by fasting, along with other fatty acid metabolism genes (Pparα, Cd36, and Aox). ATGL and HSL protein levels were also significantly induced (by 239 ± 7% and 322 ± 8%, respectively). Concomitant with changes in total protein levels, there was an increase in ATGL phosphorylation at the AMPK-regulated serine 406 site in the 14-3-3 binding motif, and an increase in HSL phosphorylation at serines 565 and 660 that are regulated by AMPK and PKA, respectively. Using immunofluorescence, we further demonstrate nearly ubiquitous expression of ATGL in the renal cortex with a concentration on the apical/lumenal surface of some cortical tubules. Our findings suggest a role for ATGL and HSL in kidney lipolysis.

scholarly journals Metabolic characteristics of a human hepatoma cell line stably transfected with hormone-sensitive lipase

1999 ◽  
Vol 341 (2) ◽  
pp. 453-460 ◽  
Author(s):  
Richard J. PEASE ◽  
David WIGGINS ◽  
E. David SAGGERSON ◽  
Jeni TREE ◽  
Geoffrey F. GIBBONS
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Hepatoma Cell ◽  
Hormone Sensitive Lipase ◽  
Acid Oxidation ◽  
Hepatoma Cell Line ◽  
Wild Type ◽  
Transfected Cells ◽  
Oxidative Pathway ◽  
Hormone Sensitive

Clones of HepG2 cells were selected that stably express the cDNA for hormone-sensitive lipase (HSL). When cells were cultured in the presence of labelled extracellular oleate, accumulation of labelled fatty acid as cellular triacylglycerol (TAG) was significantly lower in the transfectants compared with the wild-type cells. There was no change in the net rate of phospholipid (PL) synthesis. Culture of cells containing isotopically prelabelled TAG resulted in a greater net loss of TAG from the transfected cells than from the wild-type cells. The excess loss of labelled TAG was primarily due to an increased TAG fatty acid oxidation. Free fatty acid release into the medium was not increased in the transfectants, nor was the very low rate of lipoprotein lipid secretion. Also, there was no increased net trafficking of fatty acids from TAG into PLs. Changes in the 3H:14C ratio of TAG prelabelled with [3H]glycerol and [14C]oleate suggested that none of excess TAG fatty acid released in the transfected cells underwent intracellular re-esterification to TAG prior to oxidation. The results suggest that fatty acids mobilized by HSL are directed immediately into the oxidative pathway and are not available for biosynthetic processes. It appears likely, therefore, that intracellular TAG-derived fatty acids which enter the oxidative pathway exist in a different compartment from those that are directed towards synthesis.

Circulating lipids are lowered but pancreatic islet lipid metabolism and insulin secretion are unaltered in exercise-trained female rats

2007 ◽  
Vol 32 (2) ◽  
pp. 241-248 ◽  
Author(s):  
Julien Lamontagne ◽  
Pellegrino Masiello ◽  
Mariannick Marcil ◽  
Viviane Delghingaro-Augusto ◽  
Yan Burelle ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Insulin Secretion ◽  
Fatty Acid ◽  
Lipid Metabolism ◽  
Free Fatty Acids ◽  
Fatty Acid Oxidation ◽  
Female Rats ◽  
Acid Oxidation ◽  
Β Cell ◽  
Glucose Stimulated Insulin Secretion

Deteriorating islet β-cell function is key in the progression of an impaired glucose tolerance state to overt type 2 diabetes (T2D), a transition that can be delayed by exercise. We have previously shown that trained rats are protected from heart ischemia–reperfusion injury in correlation with an increase in cardiac tissue fatty-acid oxidation. This trained metabolic phenotype, if induced in the islet, could also prevent β-cell failure in the pathogenesis of T2D. To assess the effect of training on islet lipid metabolism and insulin secretion, female Sprague–Dawley rats were exercised on a treadmill for 90 min/d, 4 d/week, for 10 weeks. Islet fatty-acid oxidation, the expression of key lipid metabolism genes, and glucose-stimulated insulin secretion were determined in freshly isolated islets from trained and sedentary control rats after a 48 h rest period from the last exercise. Although this moderate training reduced plasma glycerol, free fatty acids, and triglyceride levels by about 40%, consistent with reduced lipolysis from adipose tissue, it did not alter islet fatty-acid oxidation, nor the islet expression of key transcription factors and enzymes of lipid metabolism. The training also had no effect on glucose-stimulated insulin secretion or its amplification by free fatty acids. In summary, chronic exercise training did not cause an intrinsic change in islet lipid metabolism. Training did, however, substantially reduce the exposure of islets to exogenous lipid, thereby providing a potential mechanism by which exercise can prevent islet β-cell failure leading to T2D.

Differential regulation of stimulated glucose transport by free fatty acids and PPARα or -δ agonists in cardiac myocytes

2012 ◽  
Vol 302 (7) ◽  
pp. E872-E884 ◽  
Author(s):  
Mohamed Asrih ◽  
René Lerch ◽  
Irène Papageorgiou ◽  
Corinne Pellieux ◽  
Christophe Montessuit
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Cardiac Myocytes ◽  
Glucose Transport ◽  
Fatty Acid Oxidation ◽  
Insulin Signaling ◽  
Acid Oxidation ◽  
The Impact ◽  
Stimulation Of

Stimulation of glucose transport in response to insulin or metabolic stress is an important determinant of cardiac myocyte function and survival, particularly during ischemia-reperfusion episodes. The impact of dyslipidemia and its consequence PPAR activation on stimulated glucose transport in cardiac myocytes remains unknown. Isolated adult rat cardiac myocytes were chronically exposed to free fatty acids (FFA) or PPAR agonists. Insulin- (ISGT) and oligomycin-stimulated glucose transport (OSGT) and related cell signaling were analyzed. Exposure of cardiac myocytes to FFA reduced both ISGT and OSGT. Exposure to either PPARα or PPARδ agonists, but not to a PPARγ agonist, reduced ISGT but not OSGT and increased fatty acid oxidation (FAO). The reduction in ISGT was associated with impaired insulin signaling and, in the case of PPAR stimulation, overexpression of SOCS-3, a protein known to hinder proximal insulin signaling. In contrast, the reduction of OSGT could not be explained by a reduced activity of the cellular energy-sensing system, as assessed from the maintained phosphorylation state of AMPK. Inhibition of FAO at the level of mitochondrial acylcarnitine uptake restored OSGT but not ISGT. Seemingly paradoxically, further stimulation of FAO with PPARα or PPARδ agonists also restored OSGT but not ISGT. Together, these results suggest that inhibition of OSGT occurs downstream of energy gauging and is caused by some intermediate(s) of fatty acid oxidation, which does not appear to be acylcarnitines. The results indicate that the mechanisms underlying FFA-mediated inhibition of ISGT and OSGT differ remarkably.

scholarly journals Mitochondrial Fission Governed by Drp1 Regulates Exogenous Fatty Acid Usage and Storage in Hela Cells

Metabolites ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 322
Author(s):  
Jae-Eun Song ◽  
Tiago C. Alves ◽  
Bernardo Stutz ◽  
Matija Šestan-Peša ◽  
Nicole Kilian ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Lipid Droplets ◽  
Mitochondrial Fission ◽  
Acid Oxidation ◽  
Mitochondrial Morphology ◽  
Mitochondrial Fatty Acid Oxidation ◽  
Mitochondrial Fatty Acid ◽  
And Storage

In the presence of high abundance of exogenous fatty acids, cells either store fatty acids in lipid droplets or oxidize them in mitochondria. In this study, we aimed to explore a novel and direct role of mitochondrial fission in lipid homeostasis in HeLa cells. We observed the association between mitochondrial morphology and lipid droplet accumulation in response to high exogenous fatty acids. We inhibited mitochondrial fission by silencing dynamin-related protein 1(DRP1) and observed the shift in fatty acid storage-usage balance. Inhibition of mitochondrial fission resulted in an increase in fatty acid content of lipid droplets and a decrease in mitochondrial fatty acid oxidation. Next, we overexpressed carnitine palmitoyltransferase-1 (CPT1), a key mitochondrial protein in fatty acid oxidation, to further examine the relationship between mitochondrial fatty acid usage and mitochondrial morphology. Mitochondrial fission plays a role in distributing exogenous fatty acids. CPT1A controlled the respiratory rate of mitochondrial fatty acid oxidation but did not cause a shift in the distribution of fatty acids between mitochondria and lipid droplets. Our data reveals a novel function for mitochondrial fission in balancing exogenous fatty acids between usage and storage, assigning a role for mitochondrial dynamics in control of intracellular fuel utilization and partitioning.

Sign in / Sign up

Export Citation Format

Share Document