Comparative effects of tumour necrosis factor-α (cachectin), interleukin-1-β and tumour growth on amino acid metabolism in the rat in vivo. Absorption and tissue uptake of α-amino[1-14C]isobutyrate

The effects of acute administration of either tumour necrosis factor-alpha (cachectin) (TNF) or interleukin-1-beta (IL-1), or of tumour growth (Walker-256 carcinosarcoma), on blood amino acid concentrations and tissue alpha-amino[1-14C]isobutyrate (AIB) uptake in virgin and lactating rats were compared. Both monokines decreased the blood concentrations of those amino acids (serine, glycine, alanine and proline) transported via the A system. Tumour growth decreased the blood concentrations of serine, proline and histidine, whereas the concentrations of glutamine and leucine were increased. IL-1 decreased the intestinal absorption of AIB in all groups studied; TNF or tumour growth had no effect. Tissue AIB uptake was increased (1.5-2.5-fold) in liver, whereas it was decreased in heart and skeletal muscle of the three treatment groups (except skeletal muscle of the IL-1-treated rats). Lactating rats had lower hepatic uptake of AIB compared with livers of virgin rats. IL-1 increased the hepatic uptake of AIB in lactating rats, but not to the values seen in virgin rats treated with IL-1; there was no effect of the cytokine on muscle or mammary-gland uptake. In adrenalectomized rats, the stimulatory effect of IL-1 on hepatic AIB uptake was diminished, whereas that of TNF still persisted. IL-1 caused a marked decrease of AIB uptake in muscle and heart of adrenalectomized rats, which was accompanied by an increase in the blood concentrations of branched-chain amino acids. These effects did not occur with TNF. It is concluded that the effects of the cytokines on tissue amino acid metabolism may depend on a differential endocrine response involving glucagon and/or glucocorticoids.

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Different roles of IL-1 and TNF on hemodynamics and interorgan amino acid metabolism in awake dogs

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1992.262.3.e275 ◽

1992 ◽

Vol 262 (3) ◽

pp. E275-E281

Author(s):

R. Fukushima ◽

H. Saito ◽

K. Taniwaka ◽

T. Hiramatsu ◽

Y. Morioka ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Interleukin 1 ◽

Hemodynamic Parameters ◽

Blood Flows ◽

Hyperdynamic State ◽

Necrosis Factor ◽

Glutamine Uptake

The present study examines the effects of interleukin 1 (IL-1) and tumor necrosis factor (TNF) on various hemodynamic parameters and interorgan fluxes of amino acids, glucose, and lactate in chronically catheterized awake dogs. The dogs received 5 micrograms.kg-1.h-1 of either human recombinant IL-1 beta or TNF intravenously for 2 h. Hemodynamic parameters and substrate fluxes across the gut and liver were determined during and 2 h after discontinuation of the cytokine infusions. Substrate fluxes were calculated by blood flows and arteriovenous differences. Both IL-1 and TNF enhanced the uptake of alanine, uptake of lactate, and output of glucose by the liver. These changes were associated with elevated arterial levels of alanine and lactate while arterial levels of glucose decreased. Uptake of glutamine by the liver was reduced by either IL-1 or TNF infusions. The effects of IL-1 and TNF on the hemodynamic parameters and on gut amino acid metabolism varied with the cytokine infused. IL-1 produced hyperdynamic state, increased splanchnic blood flow, and enhanced glutamine uptake by the gut. TNF infusion did not cause a hyperdynamic state, nor did it alter the gut handling of amino acids. We conclude that IL-1 and TNF exert distinct different effects on the systemic and hemodynamic parameters and on interorgan balances of amino acids, glucose, and lactate across the gut and the liver.

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Effects of tumor necrosis factor alpha on skeletal muscle amino acid metabolism studied in-vivo.

Journal of the American College of Nutrition ◽

10.1080/07315724.1996.10718583 ◽

1996 ◽

Vol 15 (2) ◽

pp. 164-168 ◽

Cited By ~ 16

Author(s):

J A Tayek

Keyword(s):

Skeletal Muscle ◽

Amino Acid ◽

Tumor Necrosis Factor ◽

Tumor Necrosis ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Necrosis Factor Alpha ◽

Factor Alpha ◽

Necrosis Factor

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The effects of tumour necrosis factor-α (cachectin) and tumour growth on hepatic amino acid utilization in the rat

Biochemical Journal ◽

10.1042/bj2660123 ◽

1990 ◽

Vol 266 (1) ◽

pp. 123-126 ◽

Cited By ~ 13

Author(s):

J M Argilés ◽

F J López-Soriano

Keyword(s):

Amino Acid ◽

Tumour Necrosis Factor ◽

Tumour Necrosis ◽

Tumour Growth ◽

Total Amino Acid ◽

Acute Administration ◽

Acid Uptake ◽

Necrosis Factor Alpha ◽

The Individual ◽

Necrosis Factor

The effects of acute administration of tumour necrosis factor-alpha (cachectin) (TNF-alpha) or of malignant tumour growth (Walker-256 carcinosarcoma) on hepatic availability and uptake of individual amino acids were compared. The results show that, in spite of lowering the hepatic availability of alanine, aspartate, serine, glycine and proline, the cytokine increased both the total amino acid hepatic uptake and the individual uptakes of alanine, glutamate, serine, threonine, proline, lysine and arginine, while decreasing those of leucine, isoleucine and phenylalanine. Tumour burden resulted in an increase in the hepatic availability of glutamine, threonine, glycine, lysine, leucine, isoleucine, valine and phenylalanine. Total liver amino acid uptake was unaffected, whereas the individual uptakes of alanine, threonine and proline were increased and those of glutamate, glutamine, serine and leucine were decreased. When effects of the cytokine are compared with those induced by tumour growth, there are similar increases in net utilization for alanine, proline and leucine, and a 3-fold difference in the increase observed for threonine. Unmatched effects are seen for glutamate, glutamine, aspartate, glycine, lysine, arginine, valine, phenylalanine and serine.

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Independent and combined actions of interleukin-1β, tumor necrosis factor α, and glucagon on amino acid metabolism in the isolated perfused rat liver

Metabolism ◽

10.1016/0026-0495(94)90261-5 ◽

1994 ◽

Vol 43 (7) ◽

pp. 822-829 ◽

Cited By ~ 13

Author(s):

J.P. De Bandt[ ◽

S.K. Lim ◽

F. Plassart ◽

C.Coudray Lucas ◽

C. Rey ◽

...

Keyword(s):

Amino Acid ◽

Tumor Necrosis ◽

Amino Acid Metabolism ◽

Tumor Necrosis Factor Α ◽

Acid Metabolism ◽

Isolated Perfused Rat Liver ◽

Perfused Rat Liver ◽

Combined Actions ◽

Factor Α ◽

Necrosis Factor

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Effect of thyroid hormones on metabolism. II. The effect of adrenalectomy or hypophysectomy on responses of rat liver enzyme activity to L-thyroxine injection

Canadian Journal of Biochemistry ◽

10.1139/o68-021 ◽

1968 ◽

Vol 46 (2) ◽

pp. 141-150 ◽

Cited By ~ 29

Author(s):

R. A. Freedland ◽

E. H. Avery ◽

A. R. Taylor

Keyword(s):

Enzyme Activity ◽

Amino Acid ◽

Carbohydrate Metabolism ◽

Amino Acid Metabolism ◽

Acid Metabolism ◽

Marked Effect ◽

Intact Animal ◽

Liver Enzyme Activity ◽

Enzyme Systems ◽

Adrenalectomized Rats

Many enzyme activities which were increased by hydrocortisone were decreased by adrenalectomy. This effect was more apparent with enzymes related to amino acid metabolism than those related to carbohydrate metabolism. The latter, although significantly increased by hydrocortisone, did not show marked decreases after adrenalectomy. Hypophysectomy decreased the activities of many enzyme systems associated with carbohydrate metabolism more drastically than did adrenalectomy. The results with the enzymes related to amino acid metabolism were not as clear. Several of these were decreased to a greater degree after hypophysectomy than after adrenalectomy. In contrast, several enzymes were also increased above the control values after hypophysectomy. Adrenalectomy was particularly efficient in decreasing the activities of several transaminases, and hypophysectomy had a marked effect upon decreasing TPN+-linked enzyme systems.The response of several enzymes to L-thyroxine injections was decreased in magnitude or eliminated after adrenalectomy. This was particularly true for enzymes associated with carbohydrate metabolism. Several enzymes increased by L-thyroxine in intact animals were actually decreased in adrenalectomized rats after this treatment. This was particularly true for serine dehydrase and glutamic–pyruvic transaminase. These results are strongly suggestive of a thyroxine–adrenal interaction in the intact animal. Hypophysectomy had a similar effect on enzyme responses to L-thyroxine, with the exception of glutaminase. Therefore, many of the effects of hypophysectomy may actually be related to a lack of adrenal function. It was observed that the removal of the adrenal had similar effects on responses of enzyme activity after thyroxine treatment, as did pituitary removal. Certain of the enzymes were decreased to a greater extent by hypophysectomy, and others were actually increased in activity after removal of the pituitary. It therefore appears that in many enzyme systems there is a complete requirement for the pituitary and (or) adrenals for a L-thyroxine effect on enzyme activity. In other enzyme systems the dependence appears to occur but does not appear to be complete.

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