Summary
Freshly isolated and primary cultured adult rat cardiomyocytes were used to elucidate the mechanism of action of the new oral antidiabetic agent (±)-5-[4-(6-hydroxy-2, 5, 7, 8-tetramethyl-chro-man-2-yl-methoxy)benzyl]-2,4-thiazolidinedione (troglitazone) on the heart. Interaction with protein kinase C (PKC) and regulation of glucose transport were evaluated as possible sites of drug action. Acute treatment (30 min) of cardiomyocytes with troglitazone did not affect the phorbolester-induced membrane association of PKC-delta and PKC-epsilon, which represent the major isoforms present in these cells. However, under these conditions the phorboles-ter-mediated increase in membrane associated PKC activity was inhibited by 43 ± 4 % (n = 4) without affecting the basal distribution of PKC activity. In contrast to these findings, troglitazone had no acute effect on basal or insulin-stimulated glucose transport in freshly isolated cardiomyocytes; even after 120 min treatment an unaltered release of lactate was determined in the presence of the drug. After 20 h in serum-free culture troglitazone induced a dose-dependent increase in 2-deoxyglucose uptake reaching a 40-fold stimulation at 5 µmol/1. This was paralleled by a dose-dependent increase of glucose transporter-1 (GLUT1) and GLUT4 protein expression to 320 ± 80 and 156 ± 15 % of control, respectively. In addition, chronic exposure to troglitazone increased the GLUT4 abundance in a plasma membrane fraction about twofold. These data show that troglitazone exerts multiple effects on cardiomyocytes involving inhibition of PKC and regulation of glucose transporter expression and distribution. We suggest that an increased glucose supply may be beneficial for the diabetic heart and that modulation of PKC-activity could be relevant for improving insulin action in muscle tissue.
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Abbreviations
- PDD:
-
4-alpha-phorbol 12, 13-didecanoate
- PMA:
-
phorbol 12-myristate 13-acetate
- PKC:
-
protein kinase C
- GLUT:
-
glucose transporter isoform
- Hepes:
-
N-2-hydroxy-ethylpiperazine-N-2-ethanesulphonic acid.
References
Yoshioka T, Fujita T, Kanai T, Aizawa Y, Kurumada T, Hasegawa K (1989) Studies on hindered phenols and analogues. 1. Hypolipidemic and hypoglycemic agents with ability to inhibit lipid peroxidation. J Med Chem 32: 421–428
Fujiwara T, Yoshioka S, Yoshioka T, Ushiyama I, Horikoshi H (1988) Characterization of new oral antidiabetic agent CS-045: studies in KK and ob/ob mice and Zucker fatty rats. Diabetes 37: 1549–1558
Fujiwara T, Wada M, Fukuda K et al. (1991) Characterization of CS-045, a new oral antidiabetic agent, II. Effects on glycemic control and pancreatic islet structure at a late stage of the diabetic syndrome in C57BL/KsJ-db/db mice. Metabolism 40: 1213–1218
Lee M-K, Miles PDG, Khoursheed M, Gao K-M, Moossa AR, Olefsky JM (1994) Metabolic effects of troglitazone on fructose-induced insulin resistance in the rat. Diabetes 43: 1435–1439
Yoshioka S, Nishino H, Shiraki T et al. (1993) Antihyper-tensive effects of CS-045 treatment in obese Zucker rats. Metabolism 42: 75–80
Suter S, Nolan JJ, Wallance P, Gumbiner B, Olefsky JM (1992) Metabolic effects of new oral hypoglycemie agent CS-045 in NIDDM subjects. Diabetes Care 15: 193–203
Mimura K, Umeda F, Hiramatsu S et al. (1994) Effects of a new oral hypoglycemie agent (CS-045) on metabolic abnormalities and insulin resistance in type 2 diabetes. Diabet Med 11: 685–691
Nolan JJ, Ludvik B, Beerdsen P, Joyce M, Olefsky J (1994) Improvement in glucose tolerance and insulin resistance in obese subjects treated with troglitazone. N Engl J Med 331: 1188–1193
Kellerer M, Kroder G, Tippmer S et al. (1994) Troglitazone prevents glucose-induced insulin resistance of insulin receptor in rat-1 fibroblasts. Diabetes 43: 447–453
Ciaraldi TP, Gilmore A, Olefsky JM, Goldberg M, Heidenreich KA (1990) In vitro studies on the action of CS-045, a new antidiabetic agent. Metabolism 39: 1056–1062
Murano K, Inoue Y, Emoto M, Kaku K, Kaneko T (1994) CS-045, a new oral antidiabetic agent, stimulates fructose-2,6-bisphosphate production in rat hepatocytes. Eur J Pharmacol 254: 257–262
Bader S, Kiehn R, Häring HU (1993) Effect of CS-045 on the activity of insulin-receptor kinase in the skeletal muscle of insulin-resistant Zucker rats. Diabetes und Stoffwechsel 2: 55–61
Kobayashi M, Iwanishi M, Egawa K, Shigeta Y (1992) Pioglitazone increases insulin sensitivity by activating insulin receptor kinase. Diabetes 41: 476–483
Tafuri SR (1994) Troglitazone stimulates glucose uptake in 3T3-L1 adipocytes. Diabetes 43 [Suppl 1]: 761 (Abstract)
Götzsche O (1986) Myocardial cell dysfunction in diabetes mellitus. Diabetes 35: 1158–1162
Russ M, Eckel J (1995) Insulin action on cardiac glucose transport: studies on the role of protein kinase C. Biochim Biophys Acta 1265: 73–78
Eckel J, Asskamp B, Reinauer H (1991) Induction of insulin resistance in primary cultured adult cardiomyocytes. Endocrinology 129: 345–352
Bähr M, von Holtey M, Müller G, Eckel J (1995) Direct stimulation of myocardial glucose transport and glucose transport-1 (GLUT1) and GLUT4 protein expression by the sulfonylurea glimepiride. Endocrinology 136: 2547–2553
Eckel J, Pandalis G, Reinauer H (1983) Insulin action on glucose transport system in isolated cardiocytes from adult rat. Biochem J 21: 385–392
Hohorst HU (1963) Enzymatic determination of L-(+)-lac-tate. In: Bergmeyer HU (ed) Methods of enzymatic analysis. Academic Press, New York, pp 266–270
Kolter T, Uphues I, Wichelhaus A, Reinauer H, Eckel J (1992) Contraction-induced translocation of the glucose transporter GLUT4 in isolated ventricular cardiomyocytes. Biochem Biophys Res Commun 189: 1207–1214
Wichelhaus A, Russ M, Petersen S, Eckel J (1994) G protein expression and adenylate cyclase regulation in ventricular cardiomyocytes from STZ-diabetic rats. Am J Physiol 267: H548-H555
Takayama S, White MF, Kahn CR (1988) Phorbolester-in-duced serine phosphorylation of the insulin receptor decreases its tyrosine kinase activity. J Biol Chem 263: 3440–3447
Rybin VO, Steinberg SF (1994) Protein kinase C isoform expression and regulation in the developing heart. Circ Res 74: 299–309
Puceat M, Hilal-Dandan R, Strulovici B, Brunton LL, Brown JH (1994) Differential regulation of protein kinase C isoforms in isolated neonatal and adult rat cardiomyocytes. J Biol Chem 269: 16938–16944
Slieker LJ, Sundell KL, Bush KA, Sage SW, Fitch L, Schmiegel K (1994) Thiazolidinediones stimulate 2-deoxy-glucose uptake into G9 myocytes secondary to inhibition of oxidative phosphorylation. Diabetes 43 [Suppl 1]: 399 (Abstract)
Häring HU, Mehnert H (1993) Pathogenesis of type 2 (non-insulin-dependent) diabetes mellitus: candidates for a signal transmitter defect causing insulin resistance of the skeletal muscle. Diabetologia 36: 176–182
Takino H, Okuno S, Uotani S et al. (1994) Increased insulin responsiveness after CS-045 treatment in diabetes associated with Werner’s syndrome. Diabetes Res Clin Pract 24: 167–172
Ohsumi J, Sakakibara S, Yamaguchi J et al. (1994) Troglitazone prevents the inhibitory effects of inflammatory cyto-kines on insulin-induced adipocyte differentiation in 3T3-Ll cells. Endocrinology 135: 2279–2282
Takayama S, White MF, Lauris V, Kahn CR (1984) Phorbol ester modulate insulin receptor phosphorylation and insulin action in cultured hepatoma cells. Proc Natl Acad Sci USA 81: 7797–7801
Häring HU, Kirsch D, Obermaier B, Ermel B, Machicao F (1986) Tumor promoting phorbol esters increase the Km of the ATP-binding site of the insulin receptor kinase from rat adipocytes. J Biol Chem 261: 3869–3875
Chin JE, Liu F, Roth RA (1994) Activation of protein kinase C alpha inhibits insulin-stimulated tyrosine phosphorylation of insulin receptor substrate-1. Mol Endo 8: 51–58
Draznin B, Leitner JW, Sussman KE, Sherman NA (1988) Insulin and glucose modulate protein kinase C activity in rat adipocytes. Biochem Biophys Res Commun 156: 570–575
Farese RV, Standaert ML, Francois AJ et al. (1992) Effects of insulin and phorbol esters on subcellular distribution of protein kinase C isoforms in rat adipocytes. Biochem J 288: 319–323
Masuda K, Okamoto Y, Tsuura Y et al. (1995) Effects of troglitazone (CS-045) on insulin secretion in isolated rat pancreatic islets and HIT cells: an insulinotropic mechanism distinct from glibenclamide. Diabetologia 38: 24–30
Katz AM (1977) Physiology of the heart. Raven, New York
Shimabukuro M, Shinzato T, Higa S et al. (1995) Long-term troglitazone treatment preserves cardiac function of streptozotocin-induced diabetic rat. Diabetes 44 [Suppl 1]: 797 (Abstract)
Kraegen EW, Sowden JA, Halstead MB et al. (1993) Glucose transporters and in vivo glucose uptake in skeletal and cardiac muscle: fasting, insulin stimulation and immunoisolation studies of Glut1 and GIut4. Biochem J 295: 287–293
Uphues I, Kolter T, Goud B, Eckel J (1995) Failure of insulin-regulated recruitment of the glucose transporter GLUT4 in cardiac muscle of obese Zucker rats is associated with alterations of small-molecular-mass GTP-binding proteins. Biochem J 311: 161–166
Garvey WT, Hardin D, Juhaszova M, Dominguez JH (1993) Effects of diabetes on myocardial glucose transport system in rat: implications for diabetic cardiomyopathy. Am J Physiol 264: H837-H844
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Bähr, M., Spelleken, M., Bock, M. et al. Acute and chronic effects of troglitazone (CS-045) on isolated rat ventricular cardiomyocytes. Diabetologia 39, 766–774 (1996). https://doi.org/10.1007/s001250050509
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DOI: https://doi.org/10.1007/s001250050509