Abstract
The effects of aliphatic 2-oxocarboxylic acids, at concentrations of up to 40mm, on the function of pancreatic islets from ob/ob (obese–hyperglycaemic) mice were investigated. 1. 2-Oxopentanoate, dl-3-methyl-2-oxopentanoate, 4-methyl-2-oxopentanoate and 2-oxohexanoate all induced insulin release by isolated incubated islets and a biphasic insulin-secretory pattern in perfused mouse pancreas. The last two substances were similar in potency to glucose. Pyruvate, 2-oxobutyrate, 3-methyl-2-oxobutyrate and 2-oxo-octanoate did not induce insulin release significantly. 2. 2-Oxocarboxylic acids with significant insulin-secretory potency also induced significant 45Ca uptake by isolated incubated islets. 3. The rates of decarboxylation of [1-14C]pyruvate, 3-methyl-2-oxo[1-14C]butyrate and 4-methyl-2-oxo[1-14C]pentanoate were twice as high as the rates of oxidation of the corresponding U-14C-labelled compounds. However, whereas the rates of metabolism of labelled pyruvate and 3-methyl-2-oxobutyrate steadily increased over the concentration range 1–40mm, those of labelled 4-methyl-2-oxopentanoate and d-[U-14C]glucose levelled off at concentrations above 10mm. 4. Omission of 40CaCl2 from the incubation medium reduced the rate of oxidation of the insulin secretagogue [U-14C]4-methyl-2-oxopentanoate, but left that of the non-(insulin secretagogue) [U-14C]3-methyl-2-oxobutyrate unaffected. 5. Only glucose, and not pyruvate, 3-methyl-2-oxobutyrate and 4-methyl-2-oxopentanoate, significantly inhibited oxidation of endogenous fatty acids. 6. It is suggested that stimulus–secretion coupling and the resulting exocytosis of insulin in pancreatic β-cells may modulate both fuel oxidation and 45Ca uptake.
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- Ashcroft S. J., Hedeskov C. J., Randle P. J. Glucose metabolism in mouse pancreatic islets. Biochem J. 1970 Jun;118(1):143–154. doi: 10.1042/bj1180143. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Berne C. The metabolism of lipids in mouse pancreatic islets. The oxidation of fatty acids and ketone bodies. Biochem J. 1975 Dec;152(3):661–666. doi: 10.1042/bj1520661. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bernstein R. M., Davis B. M., Olefsky J. M., Reaven G. M. Hepatic insulin responsiveness in patients with endogenous hypertriglyceridaemia. Diabetologia. 1978 Apr;14(4):249–253. doi: 10.1007/BF01219424. [DOI] [PubMed] [Google Scholar]
- Billington D., Osmundsen H., Sherratt H. S. Mechanisms of the metabolic disturbances caused by hypoglycin and by pent-4-enoic acid. In vitro studies. Biochem Pharmacol. 1978;27(24):2879–2890. doi: 10.1016/0006-2952(78)90204-6. [DOI] [PubMed] [Google Scholar]
- Bowden J. A., Connelly J. L. Branched chain alpha-keto acid metabolism. II. Evidence for the common identity of alpha-ketoisocaproic acid and alpha-keto-beta-methyl-valeric acid dehydrogenases. J Biol Chem. 1968 Jun 25;243(12):3526–3531. [PubMed] [Google Scholar]
- Coore H. G., Randle P. J. Regulation of insulin secretion studied with pieces of rabbit pancreas incubated in vitro. Biochem J. 1964 Oct;93(1):66–78. doi: 10.1042/bj0930066. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grodsky G. M. A threshold distribution hypothesis for packet storage of insulin and its mathematical modeling. J Clin Invest. 1972 Aug;51(8):2047–2059. doi: 10.1172/JCI107011. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gunnarsson R., Hellerström C. Acute effects of alloxan on the metabolism and insulin secretion of the pancreatic B-cell. Horm Metab Res. 1973 Nov;5(6):404–409. doi: 10.1055/s-0028-1093913. [DOI] [PubMed] [Google Scholar]
- Hedeskov C. J., Hertz L., Nissen C. The effect of mannoheptulose on glucose- and pyruvate-stimulated oxygen uptake in normal mouse pancreatic islets. Biochim Biophys Acta. 1971 Feb 28;261(2):388–397. doi: 10.1016/0304-4165(72)90063-3. [DOI] [PubMed] [Google Scholar]
- Hellman B., Idahl L. A., Lenzen S., Sehlin J., Täljedal I. B. Further studies on the relationship between insulin release and lanthanum-nondisplaceable 45Ca2+ uptake by pancreatic islets: effects of fructose and starvation. Endocrinology. 1978 Jun;102(6):1856–1863. doi: 10.1210/endo-102-6-1856. [DOI] [PubMed] [Google Scholar]
- Hellman B., Idahl L. A., Lernmark A., Sehlin J., Täljedal I. B. The pancreatic beta-cell recognition of insulin secretagogues. Effects of calcium and sodium on glucose metabolism and insulin release. Biochem J. 1974 Jan;138(1):33–45. doi: 10.1042/bj1380033. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hellman B., Sehlin J., Täljedal I. B. Effects of glucose and other modifiers of insulin release on the oxidative metabolism of amino acids in micro-dissected pancreatic islets. Biochem J. 1971 Jul;123(4):513–521. doi: 10.1042/bj1230513. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hellman B., Sehlin J., Täljedal I. B. Effects of glucose on 45Ca2+ uptake by pancreatic islets as studied with the lanthanum method. J Physiol. 1976 Jan;254(3):639–656. doi: 10.1113/jphysiol.1976.sp011250. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hellman B. Studies in obese-hyperglycemic mice. Ann N Y Acad Sci. 1965 Oct 8;131(1):541–558. doi: 10.1111/j.1749-6632.1965.tb34819.x. [DOI] [PubMed] [Google Scholar]
- Henquin J. C. Relative importance of extracellular and intracellular calcium for the two phases of glucose-stimulated insulin release: studies with theophylline. Endocrinology. 1978 Mar;102(3):723–730. doi: 10.1210/endo-102-3-723. [DOI] [PubMed] [Google Scholar]
- Jain K., Asina S., Logothetopoulos J. Stimulation of proinsulin biosynthesis and insulin release by pyruvate and lactate. Biochem J. 1978 Oct 15;176(1):31–37. doi: 10.1042/bj1760031. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Johnson W. A., Connelly J. L. Cellular localization and characterization of bovine liver branched-chain -keto acid dehydrogenases. Biochemistry. 1972 May 9;11(10):1967–1973. doi: 10.1021/bi00760a036. [DOI] [PubMed] [Google Scholar]
- Lenzen S. Effects of alpha-ketocarboxylic acids and 4-pentenoic acid on insulin secretion from the perfused rat pancreas. Biochem Pharmacol. 1978 May 1;27(9):1321–1324. doi: 10.1016/0006-2952(78)90114-4. [DOI] [PubMed] [Google Scholar]
- Lenzen S. Insulin secretion by isolated perfused rat and mouse pancreas. Am J Physiol. 1979 Apr;236(4):E391–E400. doi: 10.1152/ajpendo.1979.236.4.E391. [DOI] [PubMed] [Google Scholar]
- Lenzen S., Joost H. G., Hasselblatt A. The inhibition of insulin secretion from the perfused rat pancreas after thyroxine treatment. Diabetologia. 1976 Oct;12(5):495–500. doi: 10.1007/BF01219514. [DOI] [PubMed] [Google Scholar]
- Lenzen S., Panten U., Hasselblatt A. Thyroxine treatment and insulin secretion in the rat. Diabetologia. 1975 Feb;11(1):49–55. doi: 10.1007/BF00422818. [DOI] [PubMed] [Google Scholar]
- Lin B. J., Haist R. E. Respiration and insulin synthesis in the islets of Langerhans. Can J Physiol Pharmacol. 1971 Jun;49(6):559–567. doi: 10.1139/y71-072. [DOI] [PubMed] [Google Scholar]
- Malaisse W. J., Sener A., Herchuelz A., Hutton J. C. Insulin release: the fuel hypothesis. Metabolism. 1979 Apr;28(4):373–386. doi: 10.1016/0026-0495(79)90111-2. [DOI] [PubMed] [Google Scholar]
- Panten U., Christians J., von Kriegstein E., Poser W., Hasselblatt A. Studies on the mechanism of L-leucine-and alpha-ketoisocaproic acid-induced insulin release from perifused isolated pancreatic islets. Diabetologia. 1974 Apr;10(2):149–154. doi: 10.1007/BF01219672. [DOI] [PubMed] [Google Scholar]
- Panten U. Effects of alpha-ketomonocarboxylic acids upon insulin secretion and metabolism of isolated pancreatic islets. Naunyn Schmiedebergs Arch Pharmacol. 1975;291(4):405–420. doi: 10.1007/BF00501798. [DOI] [PubMed] [Google Scholar]
- Panten U., Kriegstein E. v., Poser W., Schönborn J., Hasselblatt A. Effects of L-leucine and alpha-ketoisocaproic acid upon insulin secretion and metabolism of isolated pancreatic islets. FEBS Lett. 1972 Feb 1;20(2):225–228. doi: 10.1016/0014-5793(72)80801-9. [DOI] [PubMed] [Google Scholar]
- Parker P. J., Randle P. J. Partial purification and properties of branched-chain 2-oxo acid dehydrogenase of ox liver. Biochem J. 1978 Jun 1;171(3):751–757. doi: 10.1042/bj1710751. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rüdiger H. W., Langenbeck U., Goedde H. W. A simplified method for the preparation of 14 C-labelled branched-chain -oxo acids. Biochem J. 1972 Jan;126(2):445–446. doi: 10.1042/bj1260445. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sener A., Kawazu S., Hutton J. C., Boschero A. C., Devis G., Somers G., Herchuelz A., Malaisse W. J. The stimulus-secretion coupling of glucose-induced insulin release. Effect of exogenous pyruvate on islet function. Biochem J. 1978 Oct 15;176(1):217–232. doi: 10.1042/bj1760217. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Zaharko D. S., Beck L. V. Studies of a simplified plasma insulin immunoassaay using cellulose powder. Diabetes. 1968 Jul;17(7):444–459. doi: 10.2337/diab.17.7.444. [DOI] [PubMed] [Google Scholar]
- Zawalich W. S. Intermediary metabolism and insulin secretion from isolated rat islets of Langerhans. Diabetes. 1979 Mar;28(3):252–262. doi: 10.2337/diab.28.3.252. [DOI] [PubMed] [Google Scholar]