scholarly journals Regulation of pyruvate dehydrogenase activity in rat epididymal fat-pads and isolated adipocytes by adrenaline

1978 ◽  
Vol 174 (1) ◽  
pp. 119-130 ◽  
Author(s):  
S J Smith ◽  
E D Saggerson
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Acid Synthesis ◽  
Maximum Decrease ◽  
Isolated Adipocytes ◽  
Induced Changes ◽  
Relationship Of ◽  
The Relationship ◽  
Dose Dependent ◽  
Fat Pads

1. Dose-dependent effects of adrenaline on PDHa activity were investigated with both incubated rat epidiymal fat-pads and isolated adipocytes. 2. Adrenaline (10nM- 5 micrometer) decreased PDHa activity in fat-pads incubated with 5 mM-[U-14C]glucose + insulin (20 munits/ml). Changes in [U-14C]glucose incorporation into fatty acids in these tissues correlated only loosely with changes in PDHa activity. There was a good inverse relationship between adrenaline-induced changes in PDHa activity and increases in lipolysis (glycerol release). 3. Adrenaline (10nM - 0.5 micrometer) decreased PDHa activity in fat-pads incubated with 5 mM-[U-14C]pyruvate + insulin (20 munits/ml), whereas 1 micrometer- and 5 micrometer-adrenaline slightly increased PDHa activity. All concentrations of adrenaline tested decreased [U-14C]pyruvate incorporation into fatty acids. Between 10nM- and 0.5 micrometer-adrenaline percentage decreases in PDHa activity paralleled decreases in faty acid synthesis. 4. Effects of adrenaline on PDHa activity and fatty acid synthesis in fat-pads incubated with 5mM-[U-14C]pyruvate + insulin (20 munits/ml) could not be mimicked by addition of albumin-bound palmitate. 5. The response of PDHa activity to adrenaline (0.1 nM - 1 micrometer) in isolated adipocytes differed with the carbohydrate substrate used in the incubations. With 5 mM-glucose + insulin (20 munits/ml), PDHa activity was significantly increased by 10 nM-adrenaline, but not by 1 micrometer-adrenaline, the response to adrenaline being biphasic. There was some correlation between PDHa activity and accumulation of non-esterified fatty acids. With 5 mM-glucose alone adrenaline (0.1 nM - 1 micrometer) had no effect on PDHa activity even though lipolysis was increased by adrenaline (0.1 micrometer - 1 micrometer). With 5mM-fructose in the presence and absence of insulin, lipolytic doses of adrenaline decreased PDHa activity. No tested concentrations of adrenaline increased PDHa with this substrate. 6. In the presence of 5 mM-fructose, palmitate was significantly more effective than adrenaline with respect to the maximum decrease in PDHa activity that could be elicited. 4. The relationship of changes in PDHa activity to changes in lipogenesis and the likelihood of adrenaline-induced changes in PDHa activity being secondary to changes in non-esterified fatty acid metabolism are discussed.

scholarly journals Erhebungen zur Fettsäurenzusammensetzung von Rückenfett bei Thüringer Schweinen sowie zum Fett von Thüringer Knackwürsten aus dem Einzelhandel

2003 ◽  
Vol 46 (3) ◽  
pp. 257-267
Author(s):  
W. Reichardt ◽  
E. Gernand ◽  
S. Müller ◽  
H. Hartung ◽  
B. Eckert ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Polyunsaturated Fatty Acids ◽  
Linolenic Acid ◽  
Acid Composition ◽  
Retail Trade ◽  
Relationship Of ◽  
The Relationship

Abstract. Title of the paper: Examinations to the fatty acid composition of backfat at Thuringian pigs as well as to the fat of Thuringian cracking sausages from the retail trade The fat from the outer back bacon of Thuringian pigs (n = 751) was examined several years with regard to their fatty acid composition. The content of polyunsaturated fatty acids (PUFA) ranged at the backfat from 7.3 to 12.7% and the relationship of the n-6 and n-3 fatty acids varied from 4.4 to 11.3. PUFA contents in the backfat > 12 % were explained by high C18:2 or C18:3 contents of the food. Examination of the fatty acid composition of the fat of 21 fresh cracking sausages from the Thuringian retail trade on a random basis yielded, that the contents of PUFA and linolenic acid ranged from 6.2 to 15.8 % respectively from 0.8 to 2.0 % as well as the quotient of n-6 to n-3 fatty acids varied from 3.6 to 10.3.

The Relationship of Fasting Free Fatty Acids, Adipose Tissue, Insulin Resistance, and Fasting Glucose Concentrations with Subsequent ß-Cell Function in Nondiabetic Subjects

Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 1812-P
Author(s):  
MARIA D. HURTADO ◽  
J.D. ADAMS ◽  
MARCELLO C. LAURENTI ◽  
CHIARA DALLA MAN ◽  
CLAUDIO COBELLI ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Fatty Acids ◽  
Adipose Tissue ◽  
Free Fatty Acids ◽  
Cell Function ◽  
Fasting Glucose ◽  
Relationship Of ◽  
The Relationship

scholarly journals FSMP-15. EVALUATING THE ROLE OF LONG-CHAIN FATTY ACID METABOLISM IN PROMOTING GLIOBLASTOMA GROWTH

2021 ◽  
Vol 3 (Supplement_1) ◽  
pp. i19-i19
Author(s):  
Divya Ravi ◽  
Carmen del Genio ◽  
Haider Ghiasuddin ◽  
Arti Gaur
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Survival Rate ◽  
Tumor Progression ◽  
Acid Synthesis ◽  
Normal Brain ◽  
Acid Uptake ◽  
Exogenous Fatty Acid ◽  
Long Chain

Abstract Glioblastomas (GBM) or Stage IV gliomas, are the most aggressive of primary brain tumors and are associated with high mortality and morbidity. Patients diagnosed with this lethal cancer have a dismal survival rate of 14 months and a 5-year survival rate of 5.6% despite a multimodal therapeutic approach, including surgery, radiation therapy, and chemotherapy. Aberrant lipid metabolism, particularly abnormally active de novo fatty acid synthesis, is recognized to have a key role in tumor progression and chemoresistance in cancers. Previous studies have reported a high expression of fatty acid synthase (FASN) in patient tumors, leading to multiple investigations of FASN inhibition as a treatment strategy. However, none of these have developed as efficacious therapies. Furthermore, when we profiled FASN expression using The Cancer Genome Atlas (TCGA) we determined that high FASN expression in GBM patients did not confer a worse prognosis (HR: 1.06; p-value: 0.51) and was not overexpressed in GBM tumors compared to normal brain. Therefore, we need to reexamine the role of exogenous fatty acid uptake over de novofatty acid synthesis as a potential mechanism for tumor progression. Our study aims to measure and compare fatty acid oxidation (FAO) of endogenous and exogenous fatty acids between GBM patients and healthy controls. Using TCGA, we have identified the overexpression of multiple enzymes involved in mediating the transfer and activation of long-chain fatty acids (LCFA) in GBM tumors compared to normal brain tissue. We are currently conducting metabolic flux studies to (1) assess the biokinetics of LCFA degradation and (2) establish exogenous versus endogenous LCFA preferences between patient-derived primary GBM cells and healthy glial and immune cells during steady state and glucose-deprivation.

scholarly journals A novel acyl-CoA-binding protein from bovine liver. Effect on fatty acid synthesis

1987 ◽  
Vol 241 (1) ◽  
pp. 189-192 ◽  
Author(s):  
I B Mogensen ◽  
H Schulenberg ◽  
H O Hansen ◽  
F Spener ◽  
J Knudsen
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Binding Protein ◽  
Fatty Acid Synthetase ◽  
Bovine Liver ◽  
Acid Synthesis ◽  
Fatty Acid Binding Proteins ◽  
Fatty Acid Binding ◽  
Medium Chain ◽  
Chain Acyl

Bovine liver was shown to contain a hitherto undescribed medium-chain acyl-CoA-binding protein. The protein co-purifies with fatty-acid-binding proteins, but was, unlike these proteins, unable to bind fatty acids. The protein induced synthesis of medium-chain acyl-CoA esters on incubation with goat mammary-gland fatty acid synthetase. The possible function of the protein is discussed.

scholarly journals The regulation of glyceride synthesis in isolated white-fat cells. The effects of palmitate and lipolytic agents

1972 ◽  
Vol 128 (5) ◽  
pp. 1057-1067 ◽  
Author(s):  
E. D Saggerson
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Fat Cells ◽  
Glyceride Synthesis ◽  
Glucose Incorporation ◽  
High Concentrations ◽  
Stimulation Of

1. 0.5mm-Palmitate stimulated incorporation of [U-14C]glucose into glyceride glycerol and fatty acids in normal fat cells in a manner dependent upon the glucose concentration. 2. In the presence of insulin the incorporation of 5mm-glucose into glyceride fatty acids was increased by concentrations of palmitate, adrenaline and 6-N-2′-O-dibutyryladenosine 3′:5′-cyclic monophosphate up to 0.5mm, 0.5μm and 0.5mm respectively. Higher concentrations of these agents produced progressive decreases in the rate of glucose incorporation into fatty acids. 3. The effects of palmitate and lipolytic agents upon the measured parameters of glucose utilization were similar, suggesting that the effects of lipolytic agents are mediated through increased concentrations of free fatty acids. 4. In fat cells from 24h-starved rats, maximal stimulation of glucose incorporation into fatty acids was achieved with 0.25mm-palmitate. Higher concentrations of palmitate were inhibitory. In fat cells from 72h-starved rats, palmitate only stimulated glucose incorporation into fatty acids at high concentrations of palmitate (1mm and above). 5. The ability of fat cells to incorporate glucose into glyceride glycerol in the presence of palmitate decreased with increasing periods of starvation. 6. It is suggested that low concentrations of free fatty acids stimulate fatty acid synthesis from glucose by increasing the utilization of ATP and cytoplasmic NADH for esterification of these free fatty acids. When esterification of free fatty acids does not keep pace with their provision, inhibition of fatty acid synthesis occurs. Provision of free fatty acids far in excess of the esterification capacity of the cells leads to uncoupling of oxidative phosphorylation and a secondary stimulation of fatty acid synthesis from glucose.

scholarly journals Synthesis of fatty acids in the perfused mouse liver

1974 ◽  
Vol 142 (3) ◽  
pp. 611-618 ◽  
Author(s):  
D. Michael W. Salmon ◽  
Neil L. Bowen ◽  
Douglas A. Hems
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
De Novo ◽  
Saturated Fatty Acids ◽  
Carbon Sources ◽  
Acid Synthesis ◽  
Hepatic Glycogen ◽  
Total Rate ◽  
Glucose Carbon

1. Fatty acid synthesis de novo was measured in the perfused liver of fed mice. 2. The total rate, measured by the incorporation into fatty acid of3H from3H2O (1–7μmol of fatty acid/h per g of fresh liver), resembled the rate found in the liver of intact mice. 3. Perfusions with l-[U-14C]lactic acid and [U-14C]glucose showed that circulating glucose at concentrations less than about 17mm was not a major carbon source for newly synthesized fatty acid, whereas lactate (10mm) markedly stimulated fatty acid synthesis, and contributed extensive carbon to lipogenesis. 4. The identification of 50% of the carbon converted into newly synthesized fatty acid lends further credibility to the use of3H2O to measure hepatic fatty acid synthesis. 5. The total rate of fatty acid synthesis, and the contribution of glucose carbon to lipogenesis, were directly proportional to the initial hepatic glycogen concentration. 6. The proportion of total newly synthesized lipid that was released into the perfusion medium was 12–16%. 7. The major products of lipogenesis were saturated fatty acids in triglyceride and phospholipid. 8. The rate of cholesterol synthesis, also measured with3H2O, expressed as acetyl residues consumed, was about one-fourth of the basal rate of fatty acid synthesis. 9. These results are discussed in terms of the carbon sources of hepatic newly synthesized fatty acids, and the effect of glucose, glycogen and lactate in stimulating lipogenesis, independently of their role as precursors.

EFFECT OF ALLOXAN, INSULIN, AND THYROXINE ON CHOLESTEROL AND FATTY ACID SYNTHESIS BY RAT LIVER HOMOGENATES

1957 ◽  
Vol 35 (1) ◽  
pp. 15-23 ◽  
Author(s):  
J. F. Scaife ◽  
B. B. Migicovsky
Keyword(s):  
Carbon Dioxide ◽  
Fatty Acids ◽  
Fatty Acid ◽  
Rat Liver ◽  
Fatty Acid Synthesis ◽  
Sodium Acetate ◽  
Cholesterol Synthesis ◽  
Acid Synthesis ◽  
Liver Homogenates ◽  
Vitro Effect

The in vitro effect of alloxan and insulin on the synthesis of cholesterol and fatty acids from 1-C14-sodium acetate by rat liver homogenates has been examined. Alloxan caused a reduction in the incorporation of acetate into cholesterol, fatty acids, and C14O2, but an increase in the oxygen consumption and carbon dioxide production. The addition of insulin to homogenates caused a reduction in cholesterol synthesis but an increase in fatty acid synthesis both for normal and diabetic animals. Homogenates from thyrotoxic rats exhibited a marked reduction in cholesterol synthesis when compared with normal animals. C14O2 production by homogenates from starved rats was appreciably lower than for those from normal animals. With this exception no appreciable difference was found in the oxygen uptake, carbon dioxide, or C14O2 production in homogenates from normal, starved, thyroxine-treated, or diabetic animals. Synthesized cholesterol was found to be located principally in the particulate matter of the homogenates after they had been incubated with 1-C14-sodium acetate. Homogenates from starved rats showed no greater tendency to degrade preformed cholesterol during incubation than did those from normal rats.

scholarly journals New Insights on the Mechanism of Fatty Acids as Buccal Permeation Enhancers

Pharmaceutics ◽  
2018 ◽  
Vol 10 (4) ◽  
pp. 201 ◽  
Author(s):  
Cristina Padula ◽  
Silvia Pescina ◽  
Sara Nicoli ◽  
Patrizia Santi
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fluorescein Isothiocyanate ◽  
Penetration Enhancers ◽  
Systemic Delivery ◽  
Permeation Enhancers ◽  
Maximum Value ◽  
The Relationship ◽  
Insight Into ◽  
The Ideal

Buccal mucosa has recently received much attention as a potential route for systemic delivery of drugs, including biologics and vaccines. The aim of this work was to gain insight into the mechanism of fatty acids as buccal permeation enhancers, by studying the effect of a series of medium and long chain fatty acids on the permeation of a model high molecular weight and hydrophilic molecule, fluorescein isothiocyanate labelled dextran (FD-4, m.w. 4 kDa) across porcine esophageal epithelium. A parabolic relationship between fatty acid lipophilicity and enhancement was obtained, regardless of the presence and number of double bonds. The relationship, which resembles the well-known relationship between permeability and lipophilicity of transdermal delivery, presents a maximum value in correspondence of C10 (logP approx. 4). This is probably the ideal lipophilicity for the fatty acid to interact with the lipid domains of the mucosa. When the same analysis was performed on skin data, the same trend was observed, although the maximum value was reached for C12 (logP approx. 5), in agreement with the higher lipophilicity of the skin. The results obtained in the present work represent a significant advancement in the understanding of the mechanisms of action of fatty acids as buccal penetration enhancers.

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