Summary
Previous studies have shown that auto-antibodies against insulin receptors found in certain patients with severe insulin resistance stimulate glucose transport and metabolism in fat cell and muscle preparations. The present studies show that preincubation of rat epididymal adipose tissue with 1∶1000 dilution of one such serum results in a two fold increase in the initial activities of pyruvate dehydrogenase and acetylCoA carboxylase. These increases are similar to the maximum effects of insulin. Incubation of isolated fat cells with the serum at the same concentration also resulted in the increased phosphorylation of three intracellular proteins with subunit molecular weights of 130,000, 35,000 and 22,000 to the same extent as observed with insulin. These findings lend further support to the view that the short term effects of insulin do not involve the entry of the insulin molecule (or part thereof) into cells of target tissues.
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Czech MP (1977) Molecular basis of insulin action. Annu Rev Biochem 46:359
Goldfine ID (1978) Insulin receptors and the site of insulin action. Life Sci 23:2639
Kahn CR, Baird KL (1978) The fate of insulin bound to adipocytes. J Biol Chem 253:4900
Lawrence JC, Larner J, Kahn CR, Roth J (1978) Auto-antibodies to the insulin receptor activate glycogen synthase in rat adipocytes. Mol Cell Biochem 22:153
Kahn CR, Flier JS, Bar RS, Archer JA, Gorden P, Martin MM, Roth J (1976) The syndromes of insulin resistance and acanthosis nigricans. Insulin-receptor disorders in man N Engl J Med 294:739–745
Kahn CR, Baird K, Flier JS, Jarrett DB (1977) Effects of autoantibodies to the insulin receptor on isolated adipocytes. Studies of insulin binding and insulin action. J Clin Invest 60:1094–1106
Jarrett DB, Roth J, Kahn CR, Flier JS (1976) Direct method for the detection and characterization of cell surface receptors for insulin by means of 125I-labelled auto-antibodies against the insulin receptor. Proc Natl Acad Sci USA 73:4115
LeMarchand-Brustel Y, Gorden P, Flier JS, Kahn CR, Freychet P (1978) Anti-insulin receptor antibodies inhibit insulin binding and stimulate glucose metabolism in skeletal muscle. Diabetologia 14:311
Denton RM, Randle PJ, Bridges BJ, Cooper RH, Kerbey AL, Pask HT, Severson DL, Stansbie D, Whitehouse S (1975) Regulation of mammalian pyruvate dehydrogenase. Mol Cell Biochem 9:27
Halestrap AP, Denton RM (1974) Hormonal regulation of adipose tissue acetylCoA carboxylase by changes in the polymeric state of the enzyme. Biochem J 142:365
Denton RM, Bridges BJ, Brownsey RW, Evans GL, Hughes WA, McCormack J (1978) Acute hormonal regulation of fatty acid synthesis in mammalian tissue. In: Dils R, Knudsen J (eds) Regulation of fatty acid & glycerolipid metabolism. Pergamon Press, Oxford, p 21
Denton RM, Hughes WA (1978) Minireview, pyruvate dehydrogenase and the hormonal regulation of fat synthesis in mammalian tissues. Int J Biochem 9:545
Benjamin WB, Singer I (1975) Action of insulin, epinephrine and dibutyryl cyclic adenosine 5′-monophosphate on fat cell protein phosphorylation. Cyclic adenosine 5′-monophosphate dependent and independent mechanisms. Biochemistry 14:3301
Avruch J, Leone GR, Martin DB (1976) Identification and subcellular distribution of adipocyte peptides and phosphopeptides. J Biol Chem 251:1505
Hughes WA, Brownsey RW, Denton RM (1977) The effect of insulin on the phosphorylation of pyruvate dehydrogenase and other proteins in adipose tissue. In: Pinna LA (ed) Phosphorylated proteins and related enzymes. Information Retrieval, London, p 17
Brownsey RW, Hughes WA, Denton RM, Mayer RJ (1977) Demonstration of the phosphorylation of acetylCoA carboxylase within rat epididymal fat cells. Biochem J 168:441
Brownsey RW, Hughes WA, Denton RM (1979) Adrenaline and the regulation of acetyl-coenzyme A carboxylase in rat epididymal adipose tissue. Biochem J 184:23
Huang FL, Glinsmann WH (1976) Separation and characterization of two phosphorylase phosphatase inhibitors from rabbit skeletal muscle. Eur J Biochem 70:419
Foulkes JG, Cohen P (1979) In vivo phosphorylation of inhibitor I from rabbit skeletal muscle in response to adrenaline. Eur J Biochem 97:251
Siein MW (1975) D-Glucose determination with hexokinase and glucose-6-phosphate dehydrogenase. In: Bergmeyer HU (ed) Methods of enzymatic analysis. Academic Press, London New York, p 117
Stansbie D, Brownsey RW, Crettaz M, Denton RM (1976) Acute effects in vivo of anti-insulin serum on rates of fatty acid synthesis and activities of acetylCoA carboxylase and pyruvate dehydrogenase in liver and epididymal adipose tissue of fed rats. Biochem J 160:413
McCormack JG, Denton RM (1977) Evidence that fatty acid synthesis in the interscapular brown adipose tissue of cold adapted rats is increased in vivo by insulin by mechanisms involving paralled activation of pyruvate dehydrogenase and acetylCoA carboxylase. Biochem J 166:637
Laemmli UK (1970) Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227:680
Severson DL, Denton RM, Bridges BJ, Pask HT, Randle PJ (1976) Exchangeable and total calcium pools in mitochondria of rat epididymal fat cells. Biochem J 154:209
Kahn CR, Baird KL, Jarrett DB, Flier JS (1978) Direct demonstration that receptor crosslinking or aggregation is important in insulin action. Proc Natl Acad Sci USA 75:4209
Carpentier JL, Gorden P, Barazzone P, Freychet P, Le Cam A, Orci L (1979) Intracellular localization of 125I-labelled insulin in hepatocytes from intact rat liver. Proc Natl Acad Sci USA 76:2803–2807
Linn TC, Srere PA (1979) Identification of ATP citrate lyase as a phosphoprotein. J Biol Chem 254:1691–1698
Alexander MC, Kowaloff EM, Witters LA, Dennihy DT, Avruch J (1979) Purification of a hepatic 123,000 dalton hormone stimulated 32P-peptide and its identification as ATP citrate lyase. J Biol Chem 245:8052–8056
Smith CJ, Wejksnora PJ, Warner JR, Rubin CS, Rosen OM (1979) Insulin-stimulated protein phosphorylation in 3T3-L1 preadipocytes. Proc Natl Acad Sci USA 76:2725–2729
Cohen P, Rylatt DB, Nimmo GA (1977) The hormonal control of glycogen metabolism; the amino acid sequence at the phosphorylation site of protein phosphatase inhibitor I. FEBS Lett 76:182
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Belsham, G.J., Brownsey, R.W., Hughes, W.A. et al. Anti-insulin receptor antibodies mimic the effects of insulin on the activities of pyruvate dehydrogenase and acetylCoA carboxylase and on specific protein phosphorylation in rat epididymal fat cells. Diabetologia 18, 307–312 (1980). https://doi.org/10.1007/BF00251011
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DOI: https://doi.org/10.1007/BF00251011