Abstract
1. The activities of pyruvate dehydrogenase in rat lymphocytes and mouse macrophages are much lower than those of the key enzymes of glycolysis and glutaminolysis. However, the rates of utilization of pyruvate (at 2 mM), from the incubation medium, are not markedly lower than the rate of utilization of glucose by incubated lymphocytes or that of glutamine by incubated macrophages. This suggests that the low rate of oxidation of pyruvate produced from either glucose or glutamine in these cells is due to the high capacity of lactate dehydrogenase, which competes with pyruvate dehydrogenase for pyruvate. 2. Incubation of either macrophages or lymphocytes with dichloroacetate had no effect on the activity of subsequently isolated pyruvate dehydrogenase; incubation of mitochondria isolated from lymphocytes with dichloroacetate had no effect on the rate of conversion of [1-14C]pyruvate into 14CO2, and the double-reciprocal plot of [1-14C]pyruvate concentration against rate of 14CO2 production was linear. In contrast, ADP or an uncoupling agent increased the rate of 14CO2 production from [1-14C]pyruvate by isolated lymphocyte mitochondria. These data suggest either that pyruvate dehydrogenase is primarily in the a form or that pyruvate dehydrogenase in these cells is not controlled by an interconversion cycle, but by end-product inhibition by NADH and/or acetyl-CoA. 3. The rate of conversion of [3-14C]pyruvate into CO2 was about 15% of that from [1-14C]pyruvate in isolated lymphocytes, but was only 1% in isolated lymphocyte mitochondria. The inhibitor of mitochondrial pyruvate transport, alpha-cyano-4-hydroxycinnamate, inhibited both [1-14C]- and [3-14C]-pyruvate conversion into 14CO2 to the same extent, and by more than 80%. 4. Incubations of rat lymphocytes with concanavalin A had no effect on the rate of conversion of [1-14C]pyruvate into 14CO2, but increased the rate of conversion of [3-14C]pyruvate into 14CO2 by about 50%. This suggests that this mitogen causes a stimulation of the activity of pyruvate carboxylase.
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Selected References
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- Ardawi M. S., Newsholme E. A. Glutamine metabolism in lymphocytes of the rat. Biochem J. 1983 Jun 15;212(3):835–842. doi: 10.1042/bj2120835. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ardawi M. S., Newsholme E. A. Intracellular localization and properties of phosphate-dependent glutaminase in rat mesenteric lymph nodes. Biochem J. 1984 Jan 1;217(1):289–296. doi: 10.1042/bj2170289. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ardawi M. S., Newsholme E. A. Maximum activities of some enzymes of glycolysis, the tricarboxylic acid cycle and ketone-body and glutamine utilization pathways in lymphocytes of the rat. Biochem J. 1982 Dec 15;208(3):743–748. doi: 10.1042/bj2080743. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ardawi M. S., Newsholme E. A. Metabolism in lymphocytes and its importance in the immune response. Essays Biochem. 1985;21:1–44. [PubMed] [Google Scholar]
- Baumgarten E., Brand M. D., Pozzan T. Mechanism of activation of pyruvate dehydrogenase by mitogens in pig lymphocytes. Biochem J. 1983 Nov 15;216(2):359–367. doi: 10.1042/bj2160359. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
- Cooper R. H., Randle P. J., Denton R. M. Regulation of heart muscle pyruvate dehydrogenase kinase. Biochem J. 1974 Dec;143(3):625–641. doi: 10.1042/bj1430625. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Coore H. G., Denton R. M., Martin B. R., Randle P. J. Regulation of adipose tissue pyruvate dehydrogenase by insulin and other hormones. Biochem J. 1971 Nov;125(1):115–127. doi: 10.1042/bj1250115. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Culvenor J. G., Weidemann M. J. Phytohaemagglutinin stimulation of rat thymus lymphocytes glycolysis. Biochim Biophys Acta. 1976 Jul 21;437(2):354–363. doi: 10.1016/0304-4165(76)90005-2. [DOI] [PubMed] [Google Scholar]
- Curi R., Newsholme P., Newsholme E. A. Intracellular distribution of some enzymes of the glutamine utilisation pathway in rat lymphocytes. Biochem Biophys Res Commun. 1986 Jul 16;138(1):318–322. doi: 10.1016/0006-291x(86)90282-2. [DOI] [PubMed] [Google Scholar]
- Denton R. M., Randle P. J., Bridges B. J., Cooper R. H., Kerbey A. L., Pask H. T., Severson D. L., Stansbie D., Whitehouse S. Regulation of mammalian pyruvate dehydrogenase. Mol Cell Biochem. 1975 Oct 31;9(1):27–53. doi: 10.1007/BF01731731. [DOI] [PubMed] [Google Scholar]
- Denton R. M., Richards D. A., Chin J. G. Calcium ions and the regulation of NAD+-linked isocitrate dehydrogenase from the mitochondria of rat heart and other tissues. Biochem J. 1978 Dec 15;176(3):899–906. doi: 10.1042/bj1760899. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Denyer G. S., Kerbey A. L., Randle P. J. Kinase activator protein mediates longer-term effects of starvation on activity of pyruvate dehydrogenase kinase in rat liver mitochondria. Biochem J. 1986 Oct 15;239(2):347–354. doi: 10.1042/bj2390347. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Engel P. C., Jones J. B. Causes and elimination of erratic blanks in enzymatic metabolite assays involving the use of NAD+ in alkaline hydrazine buffers: improved conditions for the assay of L-glutamate, L-lactate, and other metabolites. Anal Biochem. 1978 Aug 1;88(2):475–484. doi: 10.1016/0003-2697(78)90447-5. [DOI] [PubMed] [Google Scholar]
- Halestrap A. P. The mitochondrial pyruvate carrier. Kinetics and specificity for substrates and inhibitors. Biochem J. 1975 Apr;148(1):85–96. doi: 10.1042/bj1480085. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hume D. A., Vijayakumar E. K., Schweinberger F., Russell L. M., Weidemann M. J. The role of calcium ions in the regulation of rat thymocyte pyruvate oxidation by mitogens. Biochem J. 1978 Sep 15;174(3):711–716. doi: 10.1042/bj1740711. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Leighton B., Budohoski L., Lozeman F. J., Challiss R. A., Newsholme E. A. The effect of prostaglandins E1, E2 and F2 alpha and indomethacin on the sensitivity of glycolysis and glycogen synthesis to insulin in stripped soleus muscles of the rat. Biochem J. 1985 Apr 1;227(1):337–340. doi: 10.1042/bj2270337. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McKeehan W. L. Glycolysis, glutaminolysis and cell proliferation. Cell Biol Int Rep. 1982 Jul;6(7):635–650. doi: 10.1016/0309-1651(82)90125-4. [DOI] [PubMed] [Google Scholar]
- Mukherjee S. P., Mukherjee C., Lynn W. S. Activation of pyruvate dehydrogenase in rat adipocytes by concanavalin A: evidence for insulin-like effect mediated by hydrogen peroxide. Biochem Biophys Res Commun. 1980 Mar 13;93(1):36–41. doi: 10.1016/s0006-291x(80)80242-7. [DOI] [PubMed] [Google Scholar]
- Myles D. D., Strong P., Sugden M. C. Errors arising from the use of [1-14C]pyruvate to measure flux through the liver pyruvate dehydrogenase complex. Biochem J. 1984 Mar 15;218(3):997–998. doi: 10.1042/bj2180997. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Newsholme P., Curi R., Gordon S., Newsholme E. A. Metabolism of glucose, glutamine, long-chain fatty acids and ketone bodies by murine macrophages. Biochem J. 1986 Oct 1;239(1):121–125. doi: 10.1042/bj2390121. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Newsholme P., Gordon S., Newsholme E. A. Rates of utilization and fates of glucose, glutamine, pyruvate, fatty acids and ketone bodies by mouse macrophages. Biochem J. 1987 Mar 15;242(3):631–636. doi: 10.1042/bj2420631. [DOI] [PMC free article] [PubMed] [Google Scholar]
- PORTZEHL H., CALDWELL P. C., RUEEGG J. C. THE DEPENDENCE OF CONTRACTION AND RELAXATION OF MUSCLE FIBRES FROM THE CRAB MAIA SQUINADO ON THE INTERNAL CONCENTRATION OF FREE CALCIUM IONS. Biochim Biophys Acta. 1964 May 25;79:581–591. doi: 10.1016/0926-6577(64)90224-4. [DOI] [PubMed] [Google Scholar]
- Randle P. J. Phosphorylation-dephosphorylation cycles and the regulation of fuel selection in mammals. Curr Top Cell Regul. 1981;18:107–129. doi: 10.1016/b978-0-12-152818-8.50013-x. [DOI] [PubMed] [Google Scholar]
- Randle P. J., Sugden P. H., Kerbey A. L., Radcliffe P. M., Hutson N. J. Regulation of pyruvate oxidation and the conservation of glucose. Biochem Soc Symp. 1978;(43):47–67. [PubMed] [Google Scholar]
- Whitehouse S., Cooper R. H., Randle P. J. Mechanism of activation of pyruvate dehydrogenase by dichloroacetate and other halogenated carboxylic acids. Biochem J. 1974 Sep;141(3):761–774. doi: 10.1042/bj1410761. [DOI] [PMC free article] [PubMed] [Google Scholar]