| 1. |
- Belfrage, Per, et al.
(author)
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Alterations of lipid metabolism in healthy volunteers during long-term ethanol intake
- 1977
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In: European Journal of Clinical Investigation. - : Wiley. - 0014-2972 .- 1365-2362. ; 7:2, s. 127-131
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Journal article (peer-reviewed)abstract
- Nine young, healthy male volunteers were given ethanol (75 g/day) for 5 weeks. The ethanol was divided into five daily doses and taken so that blood ethanol levels never exceeded 0.04% (w/v). During the latter part of the ethanol intake period, there was a significant, transient increase of plasma triglyceride (TG) concentrations followed by reduction to normal levels. A three-fold increase of lipoprotein lipase activity (LLA) occurred in biopsy specimens of adipose tissue. An increase of alpha-lipoprotein concentrations, which correlated significantly with the decrease in plasma TG levels and the increase in adipose LLA, was also observed during the ethanol intake period. No changes were observed in plasma cholesterol and beta-lipoprotein levels. A transient, three-fold increase of TG concentrations occurred in liver biopsy specimens. Ultrastructural and cytochemical examinations of the biopsy specimens showed hyperplasia of the smooth endoplasmic reticulum, and increased canallicular activity of gamma-glutamyl transferase (gamma-GT) activity in most subjects towards the end of and after the ethanol intake period. Serum gamma-GT levels also increased significantly.
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| 2. |
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| 3. |
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| 4. |
- Nilsson-Ehle, Peter, et al.
(author)
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Effects of ethanol intake on lipoprotein lipase activity in adipose tissue of fasting subjects
- 1978
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In: Lipids. - 0024-4201. ; 13:6, s. 433-437
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Journal article (peer-reviewed)abstract
- Ethanol (ca. 1 g/kg body weight) was given alone or together with glucose or lipid (mixed triglycerides) perorally to young, fasting subjects. The changes with time (0-6 hr) of lipoprotein lipase activity (LLA) in adipose tissue, plasma glycerol, triglyceride, insulin, blood glucose, and alcohol concentrations were followed. A maximal mean blood alcohol concentration of 0.09% (w/v) was obtained 1 hr after ingestion with no apparent intoxicating effects. Ethanol intake prevented the previously observed [Nilsson-Ehle, P., S. Carlstrom, and P. Belfrage, Scand, J. Clin. Lab. Invest. 35:373 (1975)] glucose-induced rapid elevation of adipose tissue LLA but had small effects on this enzymatic activity when given alone or together with lipid. Confirming results by others, ethanol intake decreased plasma glycerol concentration and increased plasma triglycerides, especially after intake of lipid. It is suggested that ethanol intake interferes with the normal carbohydrate-induced elevation of adipose tissue LLA after a mixed meal, thereby decreasing the removal capacity for circulating dietary lipid and causing enhanced and prolonged alimentary hyperlipemia.
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| 5. |
- Nilsson-Ehle, Peter, et al.
(author)
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Specific conditions for enhancement of lipoprotein lipase activity by platelets
- 1975
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In: Life Sciences. - : Elsevier BV. - 1879-0631 .- 0024-3205. ; 16:11, s. 1703-1709
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Journal article (peer-reviewed)abstract
- Homogenates of human blood platelets, but not of red blood cells, have been found to stimulate lipoprotein lipase activity only when assayed against an emulsified triglyceride substrate sonicated for a short period of time. The degree of stimulation was inversely related to the time of sonication of the substrate. Using chylomicrons as substrate no stimulation of lipoprotein lipase activity by platelet homogenate was seen.
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| 6. |
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| 7. |
- Bergström, Gunnel, et al.
(author)
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Proteolytic modification of pig and rat liver pyruvate kinase including the phosphorylatable site
- 1978
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In: Biochimica et Biophysica Acta. - 0006-3002 .- 1878-2434. ; 532:2, s. 259-267
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Journal article (peer-reviewed)abstract
- The phosphorylated or phosphate-accepting site of pyruvate kinase from pig and rat liver was removed without inactivation by incubation with subtilisin. At different time intervals the subtilisin was inactivated with phenylmethylsulfonyl fluoride and the amount of remaining phosphorylatable or phosphorylated sites of pyruvate kinase estimated by incubation with an excess of [32P]-ATP and protein kinase. It was found that to get the same rate of modification the subtilisin concentration required to modify unphosphorylated pyruvate kinase was approximately ten times higher than that used for removal of the phosphorylated site of phosphorylated site of phosphorylated enzyme. It was shown that the proteolytically-modified pyruvate kinase had an increased apparent Km for phosphoenolpyruvate without a change in V, when compared to unmodified unphosphorylated and phosphorylated pyruvate kinase. The removal of the phosphorylated site was not associated with loss of the allosteric sites for ATP and Fru-1,6-P2. The possibility that phosphorylation of the pyruvate kinase increases its degradation rate in vivo is briefly discussed.
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| 8. |
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| 9. |
- Dahlqvist, Ulla, et al.
(author)
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Endogenous substrates of protein kinase in rat liver cell sap under different dietary conditions
- 1978
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In: Biochimica et Biophysica Acta. - : Elsevier BV. - 0006-3002 .- 1878-2434 .- 0304-4165. ; 540:1, s. 13-23
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Journal article (peer-reviewed)abstract
- Liver cell sap from normally fed rats, rats fed with a high-carbohydrate diet and fasted rats was chromatographed on DEAE-cellulose (pH 7.0). The chromatogram from each diet group was analyzed for pyruvate kinase activity and endogenous substrates of cyclic AMP-stimulated protein kinase. The materials were pooled into five phosphorylatable fractions, in each of which phosphate incorporation at 0.1 mM and 1.0 mM [32P]ATP in the presence of cyclic AMP and protein kinase was determined. For characterization of the phosphorylatable components, thin-layer gel chromatography on Sephadex G-200 and polyacrylamide gel electrophoresis in detergent were used for determination of native and minimal molecular weights, respectively. Except for pyruvate kinase, eight components which incorporated at least 0.05 nmol of [32P]phosphate/g of liver were detected. The phosphorylation of four of them was stimulated by cyclic AMP. Their minimal molecular weights were 42000, 21000, 52000 and 49000. The component with a minimal molecular weight of 42000 seemed to have a native molecular weight of 160000. Both the 21000 and the 52000 component had a native molecular weight of about 110000-120000. The protein with a minimal molecular weight of 49000 could not be correlated with certainty to a native molecular weight. The proteins whose phosphorylation was not stimulated by cyclic AMP had minimal molecular weights of 54000, 39000, 34000 and 22000.
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| 10. |
- Edlund, Bror, et al.
(author)
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Amino acid sequence at the phosphorylated site of rat liver pyruvate kinase
- 1975
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In: Biochemical and Biophysical Research Communications - BBRC. - 0006-291X .- 1090-2104. ; 67:4, s. 1516-1521
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Journal article (peer-reviewed)abstract
- One dominating peptic phosphopeptide, Asx-Thr-Lys-Gly-Pro-Glx-Ile-Glx-Thr-Gly-Val-Leu-Arg-Arg-Ala-(32P)SerP-Val-Ala-Glx-Leu, was obtained from rat liver pyruvate kinase (type L) phosphorylated by cyclic 3′,5′-AMP-stimulated protein kinase from the same tissue. The sequence around the phosphorylated serine residue is similar to that of a corresponding but smaller peptic phosphopeptide previously isolated from pig liver (type L) pyruvate kinase, Leu-Arg-Arg-Ala-(32P)SerP-Leu.
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