scholarly journals Hormonal activation of type-L hormone-sensitive lipase measured in defatted heart powders

1983 ◽  
Vol 212 (2) ◽  
pp. 379-383 ◽  
Author(s):  
W K Palmer ◽  
T A Kane
Keyword(s):  
Cyclic Amp ◽  
Diethyl Ether ◽  
Rat Heart ◽  
Hormone Sensitive Lipase ◽  
Dependent Manner ◽  
Ph Optimum ◽  
Protamine Sulphate ◽  
Hormone Sensitive ◽  
The Stability ◽  
Ether Treatment

Adrenaline, 3-isobutyl-1-methylxanthine (MIX) and dibutyryl cyclic AMP (Bt2 cyclic AMP) stimulated type-L hormone-sensitive lipase (HSL) activity when measurements were made on defatted rat heart powders. These lipolytic agents stimulated the activity of this enzyme in a time- and dose-dependent manner. This activation was reversible, because removal of adrenaline from the perfusate was accompanied by the return of type-L HSL activity to control levels. We have reported [Palmer, Caruso & Oscai (1981) Biochem. J. 198, 159-166] that perfusion with low levels of adrenaline, MIX or Bt2 cyclic AMP reduced type-L HSL activity below control levels when measurements were made in aqueous homogenates. However, in the present study, when activities were measured in acetone/diethyl ether heart powders, all concentrations of these agents studied stimulated enzyme activity, and at no concentration was there enzyme inhibition. These data suggest that acetone/diethyl ether treatment may remove a factor that plays a role in type-L HSL regulation. Type-L HSL activity measured in acetone/diethyl ether powders of control and stimulated rat heart exhibited properties that include alkaline pH optimum, serum requirement, activation by heparin and inhibition by high salt and protamine sulphate. These characteristics, in addition to the stability of the enzyme to treatment with organic solvents, fulfil the requirements for the type-L HSL classification.

scholarly journals Hormone-stimulated lipolysis in cardiac myocytes

1983 ◽  
Vol 216 (1) ◽  
pp. 241-243 ◽  
Author(s):  
W K Palmer ◽  
T A Kane
Keyword(s):  
Fatty Acid ◽  
Cyclic Amp ◽  
Cardiac Myocytes ◽  
Diethyl Ether ◽  
Lipase Activity ◽  
Intracellular Concentration ◽  
Hormone Sensitive Lipase ◽  
Extracellular Compartment ◽  
Triacylglycerol Content ◽  
Hormone Sensitive

Type L hormone-sensitive lipase (HSL) activity was increased approx. 35% above control in cardiac myocytes incubated for 15 min with 5 nM-adrenaline. Concomitantly. adrenaline-stimulated myocytes had a lower triacylglycerol content, released more non-esterified fatty acid and had a higher intracellular concentration of cyclic AMP than did myocytes incubated without hormone. The lipase activity measured in adrenaline-stimulated and non-stimulated myocytes was stable in acetone/diethyl ether, stimulated by serum and inhibited by NaCl. These properties are consistent with the type L designation of this HSL. The finding that type L HSL is stimulated by adrenaline indicates that the enzyme that is being activated is found in the cell and not associated with an extracellular compartment of the myocardium.

scholarly journals Effect of Gambisan on the Inhibition of Adipogenesis in 3T3-L1 Adipocytes

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Jung Won Kang ◽  
Dongwoo Nam ◽  
Kun Hyung Kim ◽  
Jeong-Eun Huh ◽  
Jae-Dong Lee
Keyword(s):  
Dna Content ◽  
Hormone Sensitive Lipase ◽  
Dependent Manner ◽  
Rt Pcr ◽  
Hormone Sensitive ◽  
Ldh Assay ◽  
Dose Dependent ◽  
Oil Red O Staining ◽  
Oil Red O

This study was conducted to explore the antiadipogenic effect and possible mechanism of Gambisan on 3T3-L1 cells. For quality control, Gambisan was standardized by HPLC and the standard compounds ephedrine, epigallocatechin-3-gallate, and caffeine were screened. Cultured 3T3-L1 cells that had been induced to differentiate were treated with various concentrations of Gambisan or its major component extracts (Ephedra intermediaSchrenk,Atractylodes lanceaDC., andThea sinensisL.) for 72 hours for MTT assay to determine cell viability or 10 days for LDH assay, triglyceride assay, DNA content measurement, Oil red O staining, RT-PCR, and western blot. Gambisan significantly inhibited adipogenesis in 3T3-L1 cells by reducing triglyceride contents and lipid accumulation in a dose-dependent manner without obvious cytotoxicity. Viability and DNA content in 3T3-L1 cells treated with Gambisan were significantly higher than cells treated with the major component extracts at every concentration. The anti-adipogenic effects of Gambisan appeared to be mediated by a significant downregulation of the expression of lipoprotein lipase mRNA and PPARγ, C/EBPα, and SREBP-1 protein apart from the expression of hormone-sensitive lipase. Gambisan could act as a possible therapeutic agent for obesity. However, further studies includingin vivoassays and clinical trials are needed to confirm the efficacy, safety and mechanisms of the antiobesity effects of Gambisan.

scholarly journals Crotonis Fructusand Its Constituent, Croton Oil, Stimulate Lipolysis in OP9 Adipocytes

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Mi-Seong Kim ◽  
Ha-Rim Kim ◽  
Hong-Seob So ◽  
Young-Rae Lee ◽  
Hyoung-Chul Moon ◽  
...  
Keyword(s):  
Positive Control ◽  
Hormone Sensitive Lipase ◽  
Dependent Manner ◽  
Glycerol Release ◽  
Croton Oil ◽  
Croton Tiglium ◽  
Hormone Sensitive ◽  
Main Component ◽  
Culture Supernatants ◽  
Dose Dependent

Introduction. Crotonis fructus (CF) is the mature fruit ofCroton tigliumL. and has been used for the treatment of gastrointestinal disturbance in Asia. It is well known that the main component of CF is croton oil (CO). The present study is to investigate the effects of CF extracts (CFE) and CO on lipolysis in OP9 adipocytes.Methods. Glycerol release to the culture supernatants was used as a marker of adipocyte lipolysis.Results. Treatment with various concentrations of CFE and CO stimulates glycerol release in a dose-dependent manner. The increase in glycerol release by CFE is more potent than isoproterenol, which is aβ-adrenergic agonist as a positive control in our system. The increased lipolysis by CFE and CO was accompanied by an increase of phosphorylated hormone sensitive lipase (pHSL) but not nonphosphorylated HSL protein and mRNA. Pretreatment with H89, which is a protein kinase A inhibitor, significantly abolished the CFE- and CO-induced glycerol release in OP9 adipocytes. These results suggest that CFE and CO may be a candidate for the development of a lipolysis-stimulating agent in adipocytes.

scholarly journals Acetylation of Cavin-1 Promotes Lipolysis in White Adipose Tissue

2017 ◽  
Vol 37 (16) ◽  
Author(s):  
Shui-Rong Zhou ◽  
Liang Guo ◽  
Xu Wang ◽  
Yang Liu ◽  
Wan-Qiu Peng ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
White Adipose Tissue ◽  
Molecular Mechanisms ◽  
Hormone Sensitive Lipase ◽  
Dependent Manner ◽  
Nutritional Regulation ◽  
Fat Mobilization ◽  
Hormone Sensitive ◽  
Shed Light

ABSTRACT White adipose tissue (WAT) serves as a reversible energy storage depot in the form of lipids in response to nutritional status. Cavin-1, an essential component in the biogenesis of caveolae, is a positive regulator of lipolysis in adipocytes. However, molecular mechanisms of cavin-1 in the modulation of lipolysis remain poorly understood. Here, we showed that cavin-1 was acetylated at lysines 291, 293, and 298 (3K), which were under nutritional regulation in WAT. We further identified GCN5 as the acetyltransferase and Sirt1 as the deacetylase of cavin-1. Acetylation-mimetic 3Q mutants of cavin-1 augmented fat mobilization in 3T3-L1 adipocytes and zebrafish. Mechanistically, acetylated cavin-1 preferentially interacted with hormone-sensitive lipase and recruited it to the caveolae, thereby promoting lipolysis. Our findings shed light on the essential role of cavin-1 in regulating lipolysis in an acetylation-dependent manner in WAT.

Activation of nucleotide oligomerization domain containing protein 1 induces lipolysis through NF-κB and the lipolytic PKA activation in 3T3-L1 adipocytes

2013 ◽  
Vol 91 (6) ◽  
pp. 428-434 ◽  
Author(s):  
Jaanki S. Purohit ◽  
Pan Hu ◽  
Guoxun Chen ◽  
Jay Whelan ◽  
Naima Moustaid-Moussa ◽  
...  
Keyword(s):  
Hormone Sensitive Lipase ◽  
Dependent Manner ◽  
Camp Production ◽  
Nucleotide Oligomerization ◽  
Hormone Sensitive ◽  
Sirna Knockdown ◽  
Dose Dependent ◽  
Nucleotide Oligomerization Domain ◽  
Oligomerization Domain

Obesity is associated with chronic inflammation. Toll-like receptors (TLR) and NOD-like receptors (NLR) are two families of pattern recognition receptors that play important roles in the immune response and inflammation in adipocytes. Activation of TLR4 has been shown to stimulate lipolysis from adipose tissue or adipocytes. However, effects of activation of nucleotide-oligomerization domain containing protein 1 (NOD1), one of the prominent members of NLRs, on adipocyte lipolysis have not been studied. Here we report that NOD1 activation by the synthetic ligands (Tri-DAP and C12-iEDAP) stimulated lipolysis in 3T3-L1 adipocytes in a time- and dose-dependent manner. C12-iEDAP-induced lipolysis was attenuated with NOD1 siRNA knockdown, demonstrating the specificity of the effects. Moreover, inhibition of the protein kinase A (PKA)/hormone sensitive lipase (HSL) and NF-κB pathways by the pharmacological inhibitors attenuated the lipolytic effects of C12-iEDAP. Furthermore, we show NOD1 activation induced PKA activation independent of cAMP production and inhibition of NF-κB pathways attenuated phosphorylation of selected PKA lipolytic targets (phosphorylation of Perilipin Ser 517 and HSL Ser 563). Taken together, our results demonstrate a novel role of NOD1 activation, via NF-κB/PKA lipolytic activation, in inducing lipolysis in adipocytes and suggest that NOD1 activation may contribute to dyslipidemia in obesity.

scholarly journals Insulin Regulates Adipocyte Lipolysis via an Akt-Independent Signaling Pathway

2010 ◽  
Vol 30 (21) ◽  
pp. 5009-5020 ◽  
Author(s):  
Sarah M. Choi ◽  
David F. Tucker ◽  
Danielle N. Gross ◽  
Rachael M. Easton ◽  
Lisa M. DiPilato ◽  
...  
Keyword(s):  
Insulin Action ◽  
Hormone Sensitive Lipase ◽  
Dependent Manner ◽  
Impaired Insulin ◽  
Hormone Sensitive ◽  
Phosphoinositide 3 Kinase ◽  
Impaired Insulin Action ◽  
Differential Phosphorylation ◽  
Dependent Pathway ◽  
Kinase A

ABSTRACT After a meal, insulin suppresses lipolysis through the activation of its downstream kinase, Akt, resulting in the inhibition of protein kinase A (PKA), the main positive effector of lipolysis. During insulin resistance, this process is ineffective, leading to a characteristic dyslipidemia and the worsening of impaired insulin action and obesity. Here, we describe a noncanonical Akt-independent, phosphoinositide-3 kinase (PI3K)-dependent pathway that regulates adipocyte lipolysis using restricted subcellular signaling. This pathway selectively alters the PKA phosphorylation of its major lipid droplet-associated substrate, perilipin. In contrast, the phosphorylation of another PKA substrate, hormone-sensitive lipase (HSL), remains Akt dependent. Furthermore, insulin regulates total PKA activity in an Akt-dependent manner. These findings indicate that localized changes in insulin action are responsible for the differential phosphorylation of PKA substrates. Thus, we identify a pathway by which insulin regulates lipolysis through the spatially compartmentalized modulation of PKA.

Relationship between type L hormone-sensitive lipase and endogenous triacylglycerol in rat heart

1984 ◽  
Vol 247 (4) ◽  
pp. R621-R625
Author(s):  
W. C. Miller ◽  
L. B. Oscai
Keyword(s):  
Lipoprotein Lipase ◽  
Cold Exposure ◽  
Lipase Activity ◽  
Rat Heart ◽  
Hormone Sensitive Lipase ◽  
Separate Experiment ◽  
Lipoprotein Lipase Activity ◽  
Physiological Conditions ◽  
Hormone Sensitive ◽  
Fat Feeding

The purpose of this study was to determine whether, under physiological conditions, intracellular lipoprotein lipase [type L hormone-sensitive lipase (HSL)] activity varied inversely with triacylglycerol (TG) content of the heart. The results show that fasting from 7:30 A.M. to 7:30 P.M. increased type L HSL activity from 72 +/- 1 to 96 +/- 1 U/g wet wt tissue (P less than 0.001) in the myocardium. At the same time, cardiac TG stores decreased from 1.83 +/- 0.03 to 1.37 +/- 0.01 mumol/g tissue (P less than 0.001). In a separate experiment, one night of eating a fat-rich diet (60% of calories from fat) caused a 42% increase in type L HSL activity, which was accompanied by a 42% reduction in the TG content of the heart. Likewise cold exposure (overnight) activated type L HSL (73%) and, at the same time, decreased cardiac TG stores (44%). When data from the fasting, fat-feeding, and cold-exposure experiments were combined, a significant correlation coefficient of -0.81 was obtained between type L HSL activity and TG content of the heart (P less than 0.001). These data provide evidence for a physiological relationship between intracellular lipoprotein lipase activity and cardiac TG content.

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