Abstract
All glucokinase gene mutations identified to date have been localized to exons that are common to the pancreatic and hepatic isoforms of the enzyme. While impaired insulin secretion has been observed in glucokinase-deficient subjects the consequences of this mutation on hepatic glucose metabolism remain unknown. To examine this question hepatic glycogen concentration was measured in seven glucokinase-deficient subjects with normal glycosylated hemoglobin and 12 control subjects using 13C nuclear magnetic spectroscopy during a day in which three isocaloric mixed meals were ingested. The relative fluxes of the direct and indirect pathways of hepatic glycogen synthesis were also assessed using [1-13C]glucose in combination with acetaminophen to noninvasively sample the hepatic UDP-glucose pool. Average fasting hepatic glycogen content was similar in glucokinase-deficient and control subjects (279+/-20 vs 284+/-14 mM; mean+/-SEM), and increased in both groups after the meals with a continuous pattern throughout the day. However, the net increment in hepatic glycogen content after each meal was 30-60% lower in glucokinase-deficient than in the control subjects (breakfast, 46% lower, P < 0.02; lunch, 62% lower, P = 0.002; dinner; 30% lower, P = 0.04). The net increment over basal values 4 h after dinner was 105 +/-18 mM in glucokinase-deficient and 148+/-11 mM in control subjects (P = 0.04). In the 4 h after breakfast, flux through the gluconeogenic pathway relative to the direct pathway of hepatic glycogen synthesis was higher in glucokinase-deficient than in control subjects (50+/-2% vs 34+/-5%; P = 0.038). In conclusion glucokinase-deficient subjects have decreased net accumulation of hepatic glycogen and relatively augmented hepatic gluconeogenesis after meals. These results suggest that in addition to the altered beta cell function, abnormalities in liver glycogen metabolism play an important role in the pathogenesis of hyperglycemia in patients with glucokinase-deficient maturity onset diabetes of young.
Full Text
The Full Text of this article is available as a PDF (179.5 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bali D., Svetlanov A., Lee H. W., Fusco-DeMane D., Leiser M., Li B., Barzilai N., Surana M., Hou H., Fleischer N. Animal model for maturity-onset diabetes of the young generated by disruption of the mouse glucokinase gene. J Biol Chem. 1995 Sep 15;270(37):21464–21467. doi: 10.1074/jbc.270.37.21464. [DOI] [PubMed] [Google Scholar]
- Byrne M. M., Sturis J., Clément K., Vionnet N., Pueyo M. E., Stoffel M., Takeda J., Passa P., Cohen D., Bell G. I. Insulin secretory abnormalities in subjects with hyperglycemia due to glucokinase mutations. J Clin Invest. 1994 Mar;93(3):1120–1130. doi: 10.1172/JCI117064. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Clément K., Pueyo M. E., Vaxillaire M., Rakotoambinina B., Thuillier F., Passa P., Froguel P., Robert J. J., Velho G. Assessment of insulin sensitivity in glucokinase-deficient subjects. Diabetologia. 1996 Jan;39(1):82–90. doi: 10.1007/BF00400417. [DOI] [PubMed] [Google Scholar]
- DeFronzo R. A., Bonadonna R. C., Ferrannini E. Pathogenesis of NIDDM. A balanced overview. Diabetes Care. 1992 Mar;15(3):318–368. doi: 10.2337/diacare.15.3.318. [DOI] [PubMed] [Google Scholar]
- Fajans S. S. Scope and heterogeneous nature of MODY. Diabetes Care. 1990 Jan;13(1):49–64. doi: 10.2337/diacare.13.1.49. [DOI] [PubMed] [Google Scholar]
- Froguel P., Zouali H., Vionnet N., Velho G., Vaxillaire M., Sun F., Lesage S., Stoffel M., Takeda J., Passa P. Familial hyperglycemia due to mutations in glucokinase. Definition of a subtype of diabetes mellitus. N Engl J Med. 1993 Mar 11;328(10):697–702. doi: 10.1056/NEJM199303113281005. [DOI] [PubMed] [Google Scholar]
- Gidh-Jain M., Takeda J., Xu L. Z., Lange A. J., Vionnet N., Stoffel M., Froguel P., Velho G., Sun F., Cohen D. Glucokinase mutations associated with non-insulin-dependent (type 2) diabetes mellitus have decreased enzymatic activity: implications for structure/function relationships. Proc Natl Acad Sci U S A. 1993 Mar 1;90(5):1932–1936. doi: 10.1073/pnas.90.5.1932. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Grupe A., Hultgren B., Ryan A., Ma Y. H., Bauer M., Stewart T. A. Transgenic knockouts reveal a critical requirement for pancreatic beta cell glucokinase in maintaining glucose homeostasis. Cell. 1995 Oct 6;83(1):69–78. doi: 10.1016/0092-8674(95)90235-x. [DOI] [PubMed] [Google Scholar]
- Hager J., Blanché H., Sun F., Vaxillaire N. V., Poller W., Cohen D., Czernichow P., Velho G., Robert J. J., Cohen N. Six mutations in the glucokinase gene identified in MODY by using a nonradioactive sensitive screening technique. Diabetes. 1994 May;43(5):730–733. doi: 10.2337/diab.43.5.730. [DOI] [PubMed] [Google Scholar]
- Hwang J. H., Perseghin G., Rothman D. L., Cline G. W., Magnusson I., Petersen K. F., Shulman G. I. Impaired net hepatic glycogen synthesis in insulin-dependent diabetic subjects during mixed meal ingestion. A 13C nuclear magnetic resonance spectroscopy study. J Clin Invest. 1995 Feb;95(2):783–787. doi: 10.1172/JCI117727. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Iynedjian P. B., Pilot P. R., Nouspikel T., Milburn J. L., Quaade C., Hughes S., Ucla C., Newgard C. B. Differential expression and regulation of the glucokinase gene in liver and islets of Langerhans. Proc Natl Acad Sci U S A. 1989 Oct;86(20):7838–7842. doi: 10.1073/pnas.86.20.7838. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Magnuson M. A., Shelton K. D. An alternate promoter in the glucokinase gene is active in the pancreatic beta cell. J Biol Chem. 1989 Sep 25;264(27):15936–15942. [PubMed] [Google Scholar]
- Magnusson I., Rothman D. L., Jucker B., Cline G. W., Shulman R. G., Shulman G. I. Liver glycogen turnover in fed and fasted humans. Am J Physiol. 1994 May;266(5 Pt 1):E796–E803. doi: 10.1152/ajpendo.1994.266.5.E796. [DOI] [PubMed] [Google Scholar]
- Magnusson I., Rothman D. L., Katz L. D., Shulman R. G., Shulman G. I. Increased rate of gluconeogenesis in type II diabetes mellitus. A 13C nuclear magnetic resonance study. J Clin Invest. 1992 Oct;90(4):1323–1327. doi: 10.1172/JCI115997. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Matschinsky F. M. Glucokinase as glucose sensor and metabolic signal generator in pancreatic beta-cells and hepatocytes. Diabetes. 1990 Jun;39(6):647–652. doi: 10.2337/diab.39.6.647. [DOI] [PubMed] [Google Scholar]
- Matschinsky F., Liang Y., Kesavan P., Wang L., Froguel P., Velho G., Cohen D., Permutt M. A., Tanizawa Y., Jetton T. L. Glucokinase as pancreatic beta cell glucose sensor and diabetes gene. J Clin Invest. 1993 Nov;92(5):2092–2098. doi: 10.1172/JCI116809. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moore M. C., Cherrington A. D., Cline G., Pagliassotti M. J., Jones E. M., Neal D. W., Badet C., Shulman G. I. Sources of carbon for hepatic glycogen synthesis in the conscious dog. J Clin Invest. 1991 Aug;88(2):578–587. doi: 10.1172/JCI115342. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Roden M., Perseghin G., Petersen K. F., Hwang J. H., Cline G. W., Gerow K., Rothman D. L., Shulman G. I. The roles of insulin and glucagon in the regulation of hepatic glycogen synthesis and turnover in humans. J Clin Invest. 1996 Feb 1;97(3):642–648. doi: 10.1172/JCI118460. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rothman D. L., Magnusson I., Katz L. D., Shulman R. G., Shulman G. I. Quantitation of hepatic glycogenolysis and gluconeogenesis in fasting humans with 13C NMR. Science. 1991 Oct 25;254(5031):573–576. doi: 10.1126/science.1948033. [DOI] [PubMed] [Google Scholar]
- Shulman G. I., Cline G., Schumann W. C., Chandramouli V., Kumaran K., Landau B. R. Quantitative comparison of pathways of hepatic glycogen repletion in fed and fasted humans. Am J Physiol. 1990 Sep;259(3 Pt 1):E335–E341. doi: 10.1152/ajpendo.1990.259.3.E335. [DOI] [PubMed] [Google Scholar]
- Silver M. S., Joseph R. I., Chen C. N., Sank V. J., Hoult D. I. Selective population inversion in NMR. Nature. 1984 Aug 23;310(5979):681–683. doi: 10.1038/310681a0. [DOI] [PubMed] [Google Scholar]
- Stoffel M., Froguel P., Takeda J., Zouali H., Vionnet N., Nishi S., Weber I. T., Harrison R. W., Pilkis S. J., Lesage S. Human glucokinase gene: isolation, characterization, and identification of two missense mutations linked to early-onset non-insulin-dependent (type 2) diabetes mellitus. Proc Natl Acad Sci U S A. 1992 Aug 15;89(16):7698–7702. doi: 10.1073/pnas.89.16.7698. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sturis J., Kurland I. J., Byrne M. M., Mosekilde E., Froguel P., Pilkis S. J., Bell G. I., Polonsky K. S. Compensation in pancreatic beta-cell function in subjects with glucokinase mutations. Diabetes. 1994 May;43(5):718–723. doi: 10.2337/diab.43.5.718. [DOI] [PubMed] [Google Scholar]
- Sun F., Knebelmann B., Pueyo M. E., Zouali H., Lesage S., Vaxillaire M., Passa P., Cohen D., Velho G., Antignac C. Deletion of the donor splice site of intron 4 in the glucokinase gene causes maturity-onset diabetes of the young. J Clin Invest. 1993 Sep;92(3):1174–1180. doi: 10.1172/JCI116687. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Takeda J., Gidh-Jain M., Xu L. Z., Froguel P., Velho G., Vaxillaire M., Cohen D., Shimada F., Makino H., Nishi S. Structure/function studies of human beta-cell glucokinase. Enzymatic properties of a sequence polymorphism, mutations associated with diabetes, and other site-directed mutants. J Biol Chem. 1993 Jul 15;268(20):15200–15204. [PubMed] [Google Scholar]
- Tchobroutsky G. Blood glucose levels in diabetic and non-diabetic subjects. Diabetologia. 1991 Feb;34(2):67–73. doi: 10.1007/BF00500374. [DOI] [PubMed] [Google Scholar]
- Terauchi Y., Sakura H., Yasuda K., Iwamoto K., Takahashi N., Ito K., Kasai H., Suzuki H., Ueda O., Kamada N. Pancreatic beta-cell-specific targeted disruption of glucokinase gene. Diabetes mellitus due to defective insulin secretion to glucose. J Biol Chem. 1995 Dec 22;270(51):30253–30256. doi: 10.1074/jbc.270.51.30253. [DOI] [PubMed] [Google Scholar]
- Velho G., Froguel P., Clement K., Pueyo M. E., Rakotoambinina B., Zouali H., Passa P., Cohen D., Robert J. J. Primary pancreatic beta-cell secretory defect caused by mutations in glucokinase gene in kindreds of maturity onset diabetes of the young. Lancet. 1992 Aug 22;340(8817):444–448. doi: 10.1016/0140-6736(92)91768-4. [DOI] [PubMed] [Google Scholar]
- Vionnet N., Stoffel M., Takeda J., Yasuda K., Bell G. I., Zouali H., Lesage S., Velho G., Iris F., Passa P. Nonsense mutation in the glucokinase gene causes early-onset non-insulin-dependent diabetes mellitus. Nature. 1992 Apr 23;356(6371):721–722. doi: 10.1038/356721a0. [DOI] [PubMed] [Google Scholar]
- Zouali H., Vaxillaire M., Lesage S., Sun F., Velho G., Vionnet N., Chiu K., Passa P., Permutt A., Demenais F. Linkage analysis and molecular scanning of glucokinase gene in NIDDM families. Diabetes. 1993 Sep;42(9):1238–1245. doi: 10.2337/diab.42.9.1238. [DOI] [PubMed] [Google Scholar]