Journal List > Korean Diabetes J > v.32(3) > 1002215

Park, Lee, Ku, Jo, Lee, Min, Han, Kim, and Kim: The Effects of D-Chiro-Inositol on Glucose Metabolism in 3T3-L1 Cells

Abstract

Background

The target of the treatment of metabolic syndrome and diabetes is an improvement of insulin resistance. D-chiro-inositol (DCI) plays a role in a phospholipid mediating intracellular insulin action. In the previous studies, the urine level of DCI were decreased in the diabetic animal with insulin resistance. Some clinical studies showed that DCI improved a glucose level and HbA1c. Therefore we studied the relationship between DCI and glucose metabolism, especially insulin resistance.

Methods

To investigate the mechanism of DCI affecting the glucose metabolism, we examined the effects of DCI on 2-deoxyglucose uptake, gene expression of adipocytokines and AMPK pathway by using RT-PCR and western blot in 3T3-L1 cells.

Results

Insulin-stimulated 2-deoxyglucose uptake increased in DCI-treated cells by about 1.2-fold (relative to the control) and was inhibited by phosphoinositide 3-kinase (PI3 Kinase) inhibitors (Wortmanin, LY294002) and AMPK inhibitor (STO-609). In Western blot analysis, it didn't show the difference of phosphorylation of Akt and AMPK between DCI-treated group and control in 3T3-L1 cells. However, DCI decreased the gene expression of resistin in 3T3-L1 cells.

Conclusion

DCI may involve other pathway of insulin signaling, but not PI3 Kinase and AMPK signaling pathways and it may be useful in managing metabolic syndrome by improving insulin resistance through increasing glucose uptake and decreasing resistin relevant to insulin resistance.

Figures and Tables

Fig. 1
Effect of DCI on glucose uptake. DCI-induced glucose uptake is increased and is decreased by PI3 Kinase inhibitor (Wortmannin, Ly294002) and AMPK inhibitor (STO-609), relatively. After a 2 hrs starvation period, 3T3-L1 cells were preincubated with 100 µM DCI for 10 min. 5 mM NaCl was added as control for the osmtic effect. The 3T3-L1 cell were cultured in 10% FBS-DMEM media. In glucose uptake used by 2-deoxyglucose, DCI increased about 1.2 fold relative to control and inhibited by PI3 Kinase inhibitor (Wortmannin, LY294002) and AMPK inhibitor (STO-609).
kdj-32-196-g001
Fig. 2
Effects of DCI on Akt and AMPK. A. phosphorylation of Akt. B. phosphorylation of AMPK. It didn't show phosphorylation of Akt and AMPK between DCI-treated group and control. The 3T3-L1 cells were cultured in 10% FBS-DMEM media. At 30 minutes after insulin (10 µg/mL) or DCI (10 µM, 100 µM, 1 mM, 10 mM) treatment, total cell lysates were resolved by SDS-PAGE and analyzed by western blot using anti-Akt, anti-phospho (Ser473, Thr308), anti-AMPK, anti-phospho AMPK antobodies. The blot developed by ECL.
kdj-32-196-g002
Fig. 3
Effects of DCI on adipocytokines. A. Leptin gene expression after 24 hours-treatment. B. Resistin gene expression after 24 hours-treatment. Analysis of variance (ANOVA) was done among the three groups (Vehicle, DCI 100 µM and 1 mM groups). DCI 100 µM or 1 mM decreased significantly (P < 0.05) the gene expression (0.52 ± 0.18 or 0.45 ± 0.28) of resistin in 3T3-L1 cells (n = 4), compared to Vehicle group. DCI 100 µM or 1 mM did not change significantly the gene expression (0.93 ± 0.09 or 1.56 ± 0.49) of leptin in 3T3-L1 cells (n = 4), compared to Vehicle group. Extraction of total RNA and quantitative real-time RT-PCR were performed as described under Materials and Methods. Leptin and resistin gene expression normalized to β-actin mRNA level is relative to untreated control (vehicle) cells.
kdj-32-196-g003

References

1. Reaven GM. Role of insulin resistance in human disease. Diabetes. 1988. 37:1595–1607.
crossref
3. Krentz AJ. Insulin resistance. BMJ. 1996. 313:1385–1389.
4. Cefalu WT. Insulin resistance: cellular and clinical concepts. Exp Biol Med. 2001. 226:13–26.
crossref
5. Mlinar B, Marc J, Janez A, Pfeifer M. Molecular mechanisms of insulin resistance and associated diseases. Clinica Chimica Acta. 2007. 375:20–35.
crossref
6. Moller DE, Bjorbaek C, Vidal-Puig A. Candidate genes for insulin resistance. Diabetes car. 1996. 19:396–400.
crossref
7. Reaven GM. Pathophysiology of insulin resistance in human disease. Physiol Rev. 1995. 75:473–486.
crossref
8. DeFronzo RA, Bonnadonna RC, Ferrannini E. Pathogenesis of NIDDM. A ballanced overview. Diabetes Care. 1992. 15:318–368.
9. Ferrannini E, Buzziogoli G, Bonadinna R. Insulin resistance in essential hypertension. N Engl J Med. 1987. 317:350–357.
crossref
10. Shamiss A, Carroll J, Rosenthal T. Insulin reistance in secondary hypertension. Am J Hypertens. 1992. 5:26–28.
11. Polonsky KS, Sturis J, Bell GI. Seminars in Medicine of Beth Israel Hospital, Boston. Non-insulin-depenedent diabetes mellitus - genetically programmed failure of the beta cell to compensate for insulin resistance. N Engl J Med. 1996. 334:777–783.
12. Bailey CJ, Turner RC. Metformin N Engl. Med. 1996. 334:574–579.
13. Olefsky JM. Treatment of insulin resistance with peroxisome proliferator-activated receptor gamma agonist. J Clin Invest. 2000. 106:462–472.
14. Jones DR, Varela-Nieto I. The role of glycosyl-phophatidylinositol in signal transduction. Int J Biochem Cell Biol. 1998. 30:313–326.
15. Alan RS, Marvin IS, Steven J, Pedero C. Putative mediators of insulin action: Regulation of pyruvate dehydrogenase and adenylate cyclase activities. Proc Natl Acd Sci USA. 1982. 79:3513–3517.
16. Ortmeyer HK, Bodkin NL, Hansen BC, Larner J. In vivo D-chiro-inositol activates skeletal muscle glycogen synthase and inactivates glycogen phosphorylase in rhesus monkeys. J Nutr Biochem. 1995. 6:499–503.
crossref
17. Galasko GT, Abes S, Lilley K, Zhang C, Larner J. Circulating factors and insulin resistance. II The action of the novel myo-inositol cyclic 1,2-inositol phosphate phosphoglycan insulin antagonist from human in regulating pyruvate dehydrogenase phosphatase. J Clin Endocrinol Metab. 1996. 81:1051–1057.
18. Daughaday WH, Larner J. The renal excretion of inositol in normal and diabetic human being. J Clin Invest. 1954. 33:326–332.
19. Sun TH, Heimark DB, Nguygen T, Nadler JL, Larner J. Both myo-inositol to chiro-inositol epimerase activates and chiro-inositol to myo-inositol ratios are decreased in tissues of GK type 2 diabetic rats compared Wistar controls. Biochem Biophys Biophys Commun. 2002. 293:1092–1098.
20. Kennigton AS, Hill CR, Craig J, Bogardus CR, Raz I, Ortmeyer HK. Low urinary chiro-inositol excretion in noninsulin-dependent diabetes mellitus. N Engl J Med. 1990. 323:373–378.
21. Bates SH, Jones RB, Bailey CJ. Insulin-like effect of pinitol. Br J Pharmacol. 2000. 130:1944–1948.
crossref
22. Ostlund RE JR, McGill JB, Herskowitz I, Kipnis DM, Santiago JV. D-Chiro-Inositol metabolism in diabetes mellitus. Proc Natl Acad Sci USA. 1993. 90:9988–9992.
crossref
23. Shashkin PN, Shashkina EF, Fernqvist-Forbes E, Zhou YP, Grill V. Insulin mediators in man: effects of glucose ingestion and insulin resistance. Diabetologia. 1997. 40:557–563.
crossref
24. Larner J, Allan G, Kessier C, Reamer P, Gunn R, Huang LC. Phosphoinositol glycan derived mediators and insulin resistance. Prospects for diagnosis and therapy. J Basic Clin Physiol Pharmacol. 1998. 9:127–137.
crossref
25. Asplin I, Galasko G, Larner J. chiro-inositol deficiency and insulin resistance: A comparison of the chiro -inositol- and the myo-inositol-containg insulin mediators isolated from urine, hemodialysate, and muscle of control and type II diabetic subjects. Proc Natl Acad Sci USA. 1993. 90:5924–5928.
26. Orlicky DJ, Lieber JG, Morin CL, Evans RM. Synthesis and accumulation of a receptor regulatory protein associated with lipid droplet accumulation in 3T3-L1 cells. J Lipid Res. 1998. 39:1152–1161.
crossref
27. Nia JB, Roland G, David EJ. Regulated transport of the glucose transporter GLUT4 Nature molecula. biology. 2002. 3:267–277.
28. Saltiel AR, Kahn CR. Insulin signalling and the regulation of glucose and lipid metabolism. Nature. 2001. 414:799–806.
crossref
29. Kido Y, Nakae J, Accili D. The Insulin Receptor and Its Cellular Targets. J Clin Enodocrinol Metab. 2001. 86:972–979.
crossref
30. Robert VF. Insulin-Sensitive Phospholipid Signaling System and Glucose Transport. Update II. Exp Biol Med Vol. 2001. 226:283–295.
31. Chen H. Cellular inflammatory response: Novel insights for obesity and insulin resistance. Pharmacol Res. 2006. 53:469–477.
32. Zhao YF, Feng DD, Chen C. Contribution of adipocyte-derived factors to beta-cell dysfunction in diabetes. Int J Biochem Cell Biol. 2006. 38:804–819.
crossref
33. Ryu ST, Park SO, Kim SH. The Relation of Serum Adiponectin and Resistin Concentrations with Metabolic Risk Factors. J Kor Soc Endocrinol. 2005. 20:444–451.
crossref
34. Davis A, Christinansen M, Horoxitz JF, Klein S, Hellerstein MK. Effect of pinitol treatment on insulin action in subjects with insulin resistance. Diabetes Care. 2000. 23:1000–1005.
crossref
35. Kim JI, Kim JC, Kang MJ, Lee MS, Kim JJ. Effects of pinitol isolated from soybeans on glycemic control and cardiovascular risk factors in Korean patients with type II diabetes mellitus: a randomized controlled study. Eur J Clin Nutr. 2005. 59:456–458.
36. Kang MJ, Kim JI, Yoon SY, Kim JC, Cha IJ. Pinitol from soybeans postprandial blood glucose in patients with type 2 diabetes mellitus. J Med Food. 2006. 9:182–186.
38. Kahn BB, Alquier T, Carling D, Hardie DG. AMP-activated protein kinase: Ancient energy gauge provides clues to modern understanding of metabolism. Cell metab. 2005. 1:15–25.
crossref
39. Ronti T, Lupattelli G, Mannarino E. The endocrine function of adipose tissue: an update. Clin Endocrinol. 2006. 64:335–365.
crossref
40. Widajaja A, Stratton IM, Horn M, Holman RR, Turner R. Plasma leptin, obesity, and plasma insulin in type 2 diabetics. J Clin Endocrinol Metab. 1997. 82:654–657.
41. Tanizawa Y, Okuya S, Ishihara H, Asano T, Yada T. Direct stimulation of basal insulin secretion from isolated rat pancreatic beta cells. Endocrinology. 1997. 138:4513–4516.
42. McTernan CL, McTernan PG, Harte AL, Levick PI, Barnett AH. Resistin, central obesity, and type 2 diabetes. Lancet. 2002. 359:46–47.
crossref
43. Steppan CM, Bailey ST, Bhat S, Brown EJ, Banerjee RR. The hormone resistin link obesity to diabetes. Nature. 2001. 259:46–47.
44. Rajala MW, Obici S, Scherer PE, Rossetti L. Adipose-derived resistin and gut-derived resistin-like molecule-beta selectively impair insulin action on glucose production. J Clin Invest. 2003. 111:225–230.
TOOLS
Similar articles