scholarly journals Conversion of [U−14C]glucose into carbon dioxide, glycogen, cholesterol and fatty acids in liver slices from embryonic and growing chicks

1968 ◽  
Vol 108 (4) ◽  
pp. 655-661 ◽  
Author(s):  
Alan G. Goodridge
Keyword(s):  
Carbon Dioxide ◽  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Glucose Oxidation ◽  
Glycogen Synthesis ◽  
Liver Glycogen ◽  
Acid Synthesis ◽  
Low Fat Diet ◽  
Liver Slices

Incorporation of [U−14C]glucose into carbon dioxide, glycogen, cholesterol and fatty acids and of 3H2O into cholesterol and fatty acids was measured in liver slices from embryos and growing chicks. During the embryonic period, rates of incorporation were low and stable for all pathways. Fatty acid synthesis and glucose oxidation increased promptly when the chicks were fed, reaching plateau levels within 6 days. Cholesterol and glycogen synthesis increased only slightly when the birds were fed. After 5 and 11 days respectively, cholesterol and glycogen synthesis began to increase rapidly. The rate of glucose oxidation in liver slices from 4-week-old chicks was 20-fold greater than in slices of embryonic liver; glycogen, cholesterol and fatty acid synthesis had increased approximately 100-, 300- and 1000-fold respectively. The increase in the metabolism of [U−14C]glucose that occurred after hatching was probably due to the change from a high-fat non-carbohydrate diet (yolk) to a high-carbohydrate low-fat diet (mash).

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.

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 Regulation of lipogenesis. Stimulation of fatty acid synthesis in vivo and in vitro in the liver of the newly hatched chick

1970 ◽  
Vol 118 (2) ◽  
pp. 259-263 ◽  
Author(s):  
Alan G. Goodridge
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Latent Form ◽  
Triose Phosphate ◽  
Liver Slices ◽  
Stimulation Of

1. A single glucose meal stimulated the incorporation of acetate into fatty acids in liver slices. If the glucose was added in vitro, it had no effect. Fructose and glycerol in vitro markedly stimulated fatty acid synthesis from acetate. Fructose and glycerol probably by-passed a rate-controlling reaction between glucose and triose phosphate. This reaction may have been stimulated by glucose administered in vivo. 2. The stimulation of fatty acid synthesis caused by fructose did not require the synthesis of enzyme, thus indicating that fatty acid-synthesizing enzymes were present in a latent form in the livers from unfed chicks.

scholarly journals Fatty acid synthesis in the regenerating liver of the rat

1978 ◽  
Vol 170 (1) ◽  
pp. 1-8 ◽  
Author(s):  
C D Gove ◽  
D A Hems
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Partial Hepatectomy ◽  
Fatty Acid Synthesis ◽  
De Novo ◽  
Plasma Concentrations ◽  
Liver Glycogen ◽  
Acid Synthesis ◽  
Liver Cholesterol ◽  
Regenerating Liver

1. Synthesis de novo of fatty acids in the rat liver, measured per g wet wt. of tissue, was increased by a factor of about two, between 1 and 4 days after partial hepatectomy, compared with rates in sham-operated control rat livers. 2. There were no associated changes in the rates of liver cholesterol synthesis or of adipose-tissue fatty acid synthesis in rats after partial hepatectomy, compared with rates in sham-operated rats. 3. In regenerating livers, perfused under three different conditions, there was no alteration in the capacity for fatty acid synthesis compared with that of control rats. 4. The increased synthesis of fatty acids in regenerating liver was associated with insignificant increases in plasma concentrations of tricylglycerols and free fatty acids, with a decrease in content of liver glycogen, and with no change in hepatic activity of acetyl-CoA carboxylase. 5. The accelerated rate of synthesis of fatty adids in regenerating liver appears not to be due to any intrinsic alteration in hepatic capacity for fatty acid synthesis, but it may be caused by the continuous action on liver of unidentified circulating factors.

scholarly journals THE ESTIMATION OF FATTY ACID SYNTHESIS IN RAT LIVER SLICES

1953 ◽  
Vol 205 (1) ◽  
pp. 401-408
Author(s):  
Grace Medes ◽  
Morris A. Spirtes ◽  
Sidney Weinhouse
Keyword(s):  
Fatty Acid ◽  
Rat Liver ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Liver Slices

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 glucose concentration in the growth medium on the synthesis of fatty acids by the yeast Candida bogoriensis

1982 ◽  
Vol 28 (2) ◽  
pp. 223-230 ◽  
Author(s):  
Adrian J. Cutler ◽  
Robley J. Light
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Yeast Extract ◽  
Fatty Acid Synthesis ◽  
Acid Synthesis ◽  
Glucose Medium ◽  
Triglyceride Fraction ◽  
Low Glucose ◽  
Stimulation Of

The yeast Candida bogoriensis produced large quantities of an extracellular glycolipid, the diacetyl sophoroside of 13-hydroxydocosanoic acid, when grown on a standard glucose rich medium (3% glucose, 0.15% yeast extract), but not when grown on a low glucose medium (0.5% glucose, 0.4% yeast extract) (A. J. Cutler and R. J. Light. 1979. J. Biol. Chem. 254: 1944–1950). Glucose levels also affected the quantity and distribution of the free fatty acid and triglyceride fractions synthesized by this organism. Cells grown on the low glucose medium contained palmitate and stearate as the major fatty acids in these two fractions, and a 3-h incubation with [1-14C]acetate led primarily to the labeling of these two acids. Cells grown on the standard enriched glucose medium contained relatively less stearate and more behenate than the low glucose grown cells, and the incorporation of [1-14C]acetate into stearate was decreased, while that into behenate was increased.Supplementation of low glucose grown cells with glucose led to a rapid stimulation of fatty acid synthesis, primarily palmitate and stearate in the free fatty acid fraction and stearate in the triglyceride fraction. Total triglyceride began to increase a few hours after supplementation, but synthesis of the extracellular glycolipid, and hence 13-hydroxydocosanoic acid, did not occur until 12–24 h after supplementation. The stimulation by glucose of long chain fatty acid synthesis in C. bogoriensis was therefore a process distinct from the glucose stimulation of palmitate and stearate synthesis, though the two events may be causally related.

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