This Article Abstract Full Text (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kubaszek, A. Articles by Laakso, M. Search for Related Content PubMed PubMed Citation Articles by Kubaszek, A. Articles by Laakso, M.

The Association of the K121Q Polymorphism of the Plasma Cell Glycoprotein-1 Gene with Type 2 Diabetes and Hypertension Depends on Size at Birth

Department of Medicine (A.K., A.M., M.L.), University of Kuopio, 70210 Kuopio, Finland; National Public Health Institute (J.G.E.), Department of Epidemiology and Health Promotion, 00300 Helsinki, Finland; Department of Public Health (T.F.), University of Helsinki, 00300 Helsinki, Finland; and MRC Environmental Epidemiology Unit (C.O., D.J.P.B.), University of Southampton, Southampton General Hospital, 5016 6YD Southampton, United Kingdom

Address all correspondence and requests for reprints to: Markku Laakso, Professor and Chair, Department of Medicine, University of Kuopio, 70210 Kuopio, Finland. E-mail: markku.laakso{at}kuh.fi.

	Abstract

Top Abstract Introduction Subjects and Methods Results Discussion References

 
Birth weight and length serve as indicators of the intrauterine environment, and a small body size at birth is a predictor of type 2 diabetes and hypertension. Insulin is one of the growth factors regulating fetal growth. The plasma cell glycoprotein 1 (PC-1) gene impairs insulin signaling at the insulin receptor level. Therefore, we investigated whether the K121Q polymorphism of the PC-1 gene association with insulin sensitivity, insulin levels, and the prevalence of diabetes and hypertension in adult life depends on size at birth in 489 subjects born in Helsinki during 1924–1933. We found that the effect of the PC-1 gene polymorphism on insulin levels and insulin sensitivity, measured as the homeostasis model assessment for insulin resistance, depended on birth length because fasting insulin levels and insulin resistance were highest in subjects carrying the 121Q allele who were small at birth (P for interaction = 0.04 and 0.05). Additionally, in those whose birth length was up to 49 cm, the K121Q polymorphism of the PC-1 gene was associated with a 2-fold higher incidence of type 2 diabetes. Moreover, subjects who were short at birth and who had the 121Q allele had the highest incidence (31.6%) of type 2 diabetes together with hypertension. We conclude that the interaction between the K121Q polymorphism of the PC-1 gene and birth length affects insulin sensitivity and increases susceptibility to type 2 diabetes and hypertension in adulthood.

	Introduction

Top Abstract Introduction Subjects and Methods Results Discussion References

 
THE FETAL ORIGIN hypothesis proposes that adaptations to malnutrition during fetal development permanently change metabolism and predispose humans to metabolic and cardiovascular diseases in adult life (1). Because fetal adaptations include reduced growth, small size at birth is a marker of intrauterine environment. Low birth weight, thinness at birth, and short length have all been found to be associated with high rates of diabetes and hypertension (2, 3, 4, 5). Because insulin is one of the growth factors regulating fetal growth (6), adaptations to undernutrition can involve alteration in insulin action; as a result, insulin resistance can be initiated during intrauterine growth (7). Furthermore, gene expression can be permanently changed during fetal development, and therefore genes associated with insulin resistance could have different effects depending on size at birth. Indeed, the effect of the Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-2 gene on insulin sensitivity is modified by size at birth (8).

Plasma cell glycoprotein 1 (PC-1, ENPP1) is a promising candidate gene for type 2 diabetes because it inhibits autophosphorylation of insulin receptor (IR) (9) and impairs insulin signaling downstream of IR (10). PC-1 has been shown to interact directly with IR (9), and the 121Q variant (Gln121) in exon 4 has a greater inhibitory action on IR than does the 121K allele variant (Lys121) (11). Additionally, PC-1 has enzymatic activity, and it plays a role in the regulation of signaling by nucleotides (12). Moreover, the K121Q genotype has been shown to be associated with insulin resistance (13) and high glucose and insulin levels (14). No data are available on the association of the PC-1 gene polymorphism with intrauterine growth. Therefore, the aim of our study was to investigate whether the impact of the K121Q polymorphism of the PC-1 gene on insulin sensitivity, and the occurrence of diabetes and hypertension, depends on size at birth.

	Subjects and Methods

Top Abstract Introduction Subjects and Methods Results Discussion References

 
Subjects

The original epidemiological study of 7086 men and women, born as singletons at the Helsinki University Hospital during 1924–1933, has been previously described (5). A total of 647 subjects from the original cohort were invited to attend a clinical study after an overnight fast (15). DNA samples were available for 489 subjects [180 men and 309 women; mean age 70 ± 3 yr; mean body mass index (BMI) 26.5 ± 4.0 kg/m²] of the 500 participants who came to the clinic. Altogether, 94 subjects were either taking medication for type 2 diabetes or were diagnosed at the clinic, 209 were taking medication for hypertension, and 56 of them were taking medication for both.

An oral glucose tolerance test was performed with glucose and insulin measurements at baseline (0 min) and at 120 min after a 75-g glucose load. Plasma glucose was measured by a hexokinase method and insulin, proinsulin, and 32–33 split proinsulin were measured by two-site immunometric assay (16). The homeostasis model assessment for insulin resistance (HOMA-IR) was calculated using the following formula: fasting plasma glucose (mmol/liter) x fasting serum insulin (mU/liter)/22.5 (17). Serum lipid and lipoprotein concentrations were determined using standard methods.

Genotyping

Exon 4 of the PC-1 gene was amplified with PCR with a forward primer 5'-CTGTGTTCACTTTGGACATGTTG-3' and a reverse primer 5'-GACGTTGGAAGATACCAGGTTG-3' (13). The reaction was performed in a total volume of 20 µl containing 50 ng of genomic DNA, primers (0.5 µmol/µl), 0.375 U DNA polymerase (DynaZyme, Finnzymes, Espoo, Finland), and 100 µmol/liter deoxynucleotide triphosphate. PCR conditions were denaturation at 94 C for 4 min followed by 35 cycles of denaturation at 94 C for 40 sec, annealing at 62 C for 40 sec, and extension at 72 C for 40 sec with a final extension at 72 C for 4 min. The K121Q polymorphism was screened by the Eco47I restriction enzyme followed by polyacrylamide gel electrophoresis of the digested PCR products.

Statistical analysis

Data were analyzed with the SPSS/Windows program (version 10.0, SPSS Inc., Chicago, IL). Results are given as means ± SD unless differently indicated. Multiple linear regression was applied to compare the effect of the polymorphism on continuous variables after adjustment for age, sex, and current BMI. Plasma glucose, insulin, proinsulin, high-density lipoprotein cholesterol, and triglyceride values were log transformed before statistical analyses to achieve a normal distribution. Comparisons were made within length categories and within genotypes.

	Results

Top Abstract Introduction Subjects and Methods Results Discussion References

 
The frequency of the 121Q allele was 12.9% and did not differ from previous reports. The frequency distribution of the genotypes were in Hardy-Weinberg equilibrium. For all statistical analyses, the subjects with the Q121Q genotype (n = 9) were combined with the subjects with the K121Q genotype because of the small number of these subjects.

Subjects carrying the 121Q allele had lower ponderal index compared with subjects who had the K121K genotype, but there were no differences in birth weight and length (Table 1). BMI, systolic and diastolic blood pressures, and lipids and lipoproteins did not differ between subjects with the K121K genotype and those with the 121Q allele. Fasting glucose, 2-h glucose, insulin, and HOMA-IR did not differ between subjects with the K121K genotype and with the 121Q allele in the whole study group. The effect of the PC-1 gene polymorphism on insulin sensitivity, measured as fasting insulin levels or HOMA-IR, depended on birth length when subjects were divided into five length categories (P for interaction = 0.04 and 0.05, Table 2). Fasting insulin levels and HOMA-IR were highest in subjects carrying the 121Q allele who were small at birth. In subjects with normal size, there was no effect of the 121Q allele on insulin sensitivity.

View larger version (24K): [in this window] [in a new window]   FIG. 1. Prevalence (%) of type 2 diabetes, hypertension, and both conditions according to length at birth and the PC-1 gene polymorphism.

View larger version (14K): [in this window] [in a new window]   FIG. 2. HOMA-IR index (mean ± SEM) in subjects with type 2 diabetes and concomitant hypertension according to length at birth and the PC-1 gene polymorphism.

	Discussion

Top Abstract Introduction Subjects and Methods Results Discussion References

In our study, size at birth was related to markers of insulin resistance, such as 2-h plasma insulin level, fasting proinsulin, 32–33 split proinsulin, and HOMA-IR. We found an association of the 121Q allele with low ponderal index score, although there was no difference in birth length. This may suggest that PC-1 regulates intrauterine weight gain, as was previously shown for IGF-1 and glucokinase genes (18, 19). Subjects with the 121Q allele of the PC-1 gene can have altered response to insulin during fetal growth, resulting in decreased fetal weight gain. Insulin is an important growth determinant (6, 20, 21), especially in the third trimester, when fetal weight increases substantially. Thus, insulin sensitivity can be crucial for normal growth because subjects carrying risk genotypes, including the 121Q allele of the PC-1 gene, may be poorly adapted to undernutrition. PC-1 may affect insulin action also at the postreceptor site, but no influence of PC-1 on DNA synthesis has been found (10). Birth length may be also determined by other genes, which regulate fetal response to undernutrition and oxygen supply. Therefore, the interaction of the PC-1 gene with birth length may reflect interaction with environment or with other genes.

Subjects who had the 121Q allele of the PC-1 gene and who were short at birth were both hyperinsulinemic and insulin-resistant. They also had the highest prevalence of diabetes combined with hypertension. The prevalence of hypertension in patients with type 2 diabetes is around 60%, which is about 1.5–2 times higher than in the general population (22, 23). The causes for elevated blood pressure in patients with type 2 diabetes are unknown, but elevated blood pressure is often associated with hyperinsulinemia and insulin resistance (24, 25).

We found that the association of the 121Q allele with type 2 diabetes and hypertension was restricted to subjects who had impaired fetal growth, suggesting an interaction with environmental (for example, nutrition and oxygen supply) and genetic factors affecting intrauterine growth. The association of the PC-1 gene polymorphism with hypertension has not been previously reported. One possible mechanism explaining this association is insulin resistance. Indeed, the most insulin-resistant subjects in our study were subjects with the 121Q allele who were short at birth. These subjects also developed diabetes and hypertension (Fig. 2). Moreover, in this group, the prevalence of hypertension in subjects with diabetes was higher than in patients with diabetes in general. In hypertensive patients, insulin resistance is found mainly in skeletal muscle (26) where the PC-1 gene is expressed. However, it is also possible that the enzymatic role of PC-1 in regulating signaling by nucleotides through purinergic receptors may be important because they play a role in the development of hypertension (27, 28).

We conclude that there is an interaction between the K121Q polymorphism of the PC-1 gene and intrauterine environment. This interaction affects insulin sensitivity and increases susceptibility to type 2 diabetes and its association with hypertension.

	Footnotes

 
This work was supported by the British Heart Foundation, Finska Lakaresallskapet, the Academy of Finland, and the European Union (QLG1-CT-1999).

Abbreviations: BMI, Body mass index; HOMA-IR, homeostasis model assessment for insulin resistance; IR, insulin receptor; PC-1, plasma cell glycoprotein 1.

Received August 4, 2003.

Accepted January 23, 2004.

	References

Top Abstract Introduction Subjects and Methods Results Discussion References

 

1. Barker DJ 1998 In utero programming of chronic disease. Clin Sci (Lond) 95:115–128[Medline]
2. Law CM, de Swiet M, Osmond C, Fayers PM, Barker DJ, Cruddas AM, Fall CH 1993 Initiation of hypertension in utero and its amplification throughout life. Br Med J 306:24–27
3. Hales CN, Barker DJ, Clark PM, Cox LJ, Fall C, Osmond C, Winter PD 1991 Fetal and infant growth and impaired glucose tolerance at age 64. Br Med J 303:1019–1022
4. Eriksson J, Forsen T, Tuomilehto J, Osmond C, Barker D 2000 Fetal and childhood growth and hypertension in adult life. Hypertension 36:790–794[Abstract/Free Full Text]
5. Forsen T, Eriksson J, Tuomilehto J, Reunanen A, Osmond C, Barker D 2000 The fetal and childhood growth of persons who develop type 2 diabetes. Ann Intern Med 133:176–182[Abstract/Free Full Text]
6. Vorherr H 1982 Factors influencing fetal growth. Am J Obstet Gynecol 142:577–588[Medline]
7. Phillips DI 1996 Insulin resistance as a programmed response to fetal undernutrition. Diabetologia 39:1119–1122[Medline]
8. Eriksson JG, Lindi V, Uusitupa M, Forsen TJ, Laakso M, Osmond C, Barker DJ 2002 The effects of the Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-2 gene on insulin sensitivity and insulin metabolism interact with size at birth. Diabetes 51:2321–2324[Abstract/Free Full Text]
9. Maddux BA, Goldfine ID 2000 Membrane glycoprotein PC-1 inhibition of insulin receptor function occurs via direct interaction with the receptor -subunit. Diabetes 49:13–19[Abstract]
10. Kumakura S, Maddux BA, Sung CK 1998 Overexpression of membrane glycoprotein PC-1 can influence insulin action at a post-receptor site. J Cell Biochem 68:366–377[CrossRef][Medline]
11. Costanzo BV, Trischitta V, Di Paola R, Spampinato D, Pizzuti A, Vigneri R, Frittitta L 2001 The Q allele variant (GLN121) of membrane glycoprotein PC-1 interacts with the insulin receptor and inhibits insulin signaling more effectively than the common K allele variant (LYS121). Diabetes 50:831–836[Abstract/Free Full Text]
12. Terkeltaub RA 2001 Inorganic pyrophosphate generation and disposition in pathophysiology. Am J Physiol Cell Physiol 281:C1–C11
13. Pizzuti A, Frittitta L, Argiolas A, Baratta R, Goldfine I, Bozzali M, Ercolino T, Scarlato G, Iacoviello L, Vigneri R, Tassi V, Trischitta V 1999 A polymorphism (K121Q) of the human glycoprotein PC-1 gene coding region is strongly associated with insulin resistance. Diabetes 48:1881–1884[Abstract]
14. Gu HF, Almgren P, Lindholm E, Frittitta L, Pizzuti A, Trischitta V, Groop LC 2000 Association between the human glycoprotein PC-1 gene and elevated glucose and insulin levels in a paired-sibling analysis. Diabetes 49:1601–1603[Abstract]
15. Eriksson JG, Forsen T, Tuomilehto J, Jaddoe VW, Osmond C, Barker DJ 2002 Effects of size at birth and childhood growth on the insulin resistance syndrome in elderly individuals. Diabetologia 45:342–348[CrossRef][Medline]
16. Sobey WJ, Beer SF, Carrington CA, Clark PM, Frank BH, Gray IP, Luzio SD, Owens DR, Schneider AE, Siddle K 1989 Sensitive and specific two-site immunoradiometric assays for human insulin, proinsulin, 65–66 split and 32–33 split proinsulins. Biochem J 260:535–541[Medline]
17. Matthews DR, Hosker JP, Rudenski AS, Naylor BA, Treacher DF, Turner RC 1985 Homeostasis model assessment: insulin resistance and ß-cell function from fasting plasma glucose and insulin concentration. Diabetologia 28: 412–419
18. Vaessen N, Heutink P, Janssen JA, Witteman JC, Testers L, Hofman A, Lamberts SW, Oostra BA, Pols HA, van Duijn CM 2001 A polymorphism in the gene for IGF-I: functional properties and risk for type 2 diabetes and myocardial infarction. Diabetes 50:637–642[Abstract/Free Full Text]
19. Hattersley AT, Beards F, Ballantyne E, Appleton M, Harvey R, Ellard S 1998 Mutations in the glucokinase gene of the fetus result in reduced birth weight. Nat Genet 19:268–270[CrossRef][Medline]
20. Liu KS, Wang CY, Mills N, Gyves M, Ilan J 1985 Insulin-related genes expressed in human placenta from normal and diabetic pregnancies. Proc Natl Acad Sci USA 82:3868–3870[Abstract/Free Full Text]
21. Verhaeghe J, Van Bree R, Van Herck E, Laureys J, Bouillon R, Van Assche FA 1993 C-peptide, insulin-like growth factors I and II, and insulin-like growth factor binding protein-1 in umbilical cord serum: correlations with birth weight. Am J Obstet Gynecol 169:89–97[Medline]
22. Epstein M, Sowers JR 1992 Diabetes mellitus and hypertension. Hypertension 19:403–418[Abstract]
23. Sowers JR, Epstein M, Frohlich ED 2001 Diabetes, hypertension, and cardiovascular disease: an update. Hypertension 37:1053–1059[Abstract/Free Full Text]
24. Ferrannini E, Buzzigoli G, Bonadonna R, Giorico MA, Oleggini M, Graziadei L, Pedrinelli R, Brandi L, Bevilacqua S 1987 Insulin resistance in essential hypertension. N Engl J Med 317:350–357[Abstract]
25. DeFronzo RA, Ferrannini E 1991 Insulin resistance. A multifaceted syndrome responsible for NIDDM, obesity, hypertension, dyslipidemia, and atherosclerotic cardiovascular disease. Diabetes Care 14:173–194[Abstract]
26. Capaldo B, Lembo G, Napoli R, Rendina V, Albano G, Sacca L, Trimarco B 1991 Skeletal muscle is a primary site of insulin resistance in essential hypertension. Metabolism 40:1320–1322[CrossRef][Medline]
27. Burnstock G 2002 Purinergic signaling and vascular cell proliferation and death. Arterioscler Thromb Vasc Biol 22:364–373[Abstract/Free Full Text]
28. Guimaraes S, Albino-Teixeira A 1996 Hypertension due to chronic blockade of P1-purinoceptors. J Auton Pharmacol 16:367–370[Medline]

This article has been cited by other articles:

				I. D. Goldfine, B. A. Maddux, J. F. Youngren, G. Reaven, D. Accili, V. Trischitta, R. Vigneri, and L. Frittitta The Role of Membrane Glycoprotein Plasma Cell Antigen 1/Ectonucleotide Pyrophosphatase Phosphodiesterase 1 in the Pathogenesis of Insulin Resistance and Related Abnormalities Endocr. Rev., February 1, 2008; 29(1): 62 - 75. [Abstract] [Full Text] [PDF]

				S. D. Nath, V. S. Voruganti, N. H. Arar, F. Thameem, J. C. Lopez-Alvarenga, R. Bauer, J. Blangero, J. W. MacCluer, A. G. Comuzzie, and H. E. Abboud Genome Scan for Determinants of Serum Uric Acid Variability J. Am. Soc. Nephrol., December 1, 2007; 18(12): 3156 - 3163. [Abstract] [Full Text] [PDF]

				J. G. Eriksson Gene Polymorphisms, Size at Birth, and the Development of Hypertension and Type 2 Diabetes J. Nutr., April 1, 2007; 137(4): 1063 - 1065. [Abstract] [Full Text] [PDF]

				E. Lebenthal and D. M. Bier Novel Concepts in the Developmental Origins of Adult Health and Disease J. Nutr., April 1, 2007; 137(4): 1073 - 1075. [Full Text] [PDF]

				Y. Bottcher, A. Korner, T. Reinehr, B. Enigk, W. Kiess, M. Stumvoll, and P. Kovacs ENPP1 Variants and Haplotypes Predispose to Early Onset Obesity and Impaired Glucose and Insulin Metabolism in German Obese Children J. Clin. Endocrinol. Metab., December 1, 2006; 91(12): 4948 - 4952. [Abstract] [Full Text] [PDF]

				A. Rautanen, J. G. Eriksson, J. Kere, S. Andersson, C. Osmond, P. Tienari, H. Sairanen, D. J. P. Barker, D. I. W. Phillips, T. Forsen, et al. Associations of Body Size at Birth with Late-Life Cortisol Concentrations and Glucose Tolerance Are Modified by Haplotypes of the Glucocorticoid Receptor Gene J. Clin. Endocrinol. Metab., November 1, 2006; 91(11): 4544 - 4551. [Abstract] [Full Text] [PDF]

				H. Freeman and R.D. Cox Type-2 diabetes: a cocktail of genetic discovery Hum. Mol. Genet., October 15, 2006; 15(suppl_2): R202 - R209. [Abstract] [Full Text] [PDF]

				J. Bochenski, G. Placha, K. Wanic, M. Malecki, J. Sieradzki, J. H. Warram, and A. S. Krolewski New Polymorphism of ENPP1 (PC-1) Is Associated With Increased Risk of Type 2 Diabetes Among Obese Individuals Diabetes, September 1, 2006; 55(9): 2626 - 2630. [Abstract] [Full Text] [PDF]

				S. R. de Rooij, R. C. Painter, D. I.W. Phillips, C. Osmond, M. W.T. Tanck, J. C. Defesche, P. M.M. Bossuyt, R. P.J. Michels, O. P. Bleker, and T. J. Roseboom The Effects of the Pro12Ala Polymorphism of the Peroxisome Proliferator-Activated Receptor-{gamma}2 Gene on Glucose/Insulin Metabolism Interact With Prenatal Exposure to Famine Diabetes Care, May 1, 2006; 29(5): 1052 - 1057. [Abstract] [Full Text] [PDF]

				S. Bacci, O. Ludovico, S. Prudente, Y.-Y. Zhang, R. Di Paola, D. Mangiacotti, A. Rauseo, D. Nolan, J. Duffy, G. Fini, et al. The K121Q Polymorphism of the ENPP1/PC-1 Gene Is Associated With Insulin Resistance/Atherogenic Phenotypes, Including Earlier Onset of Type 2 Diabetes and Myocardial Infarction Diabetes, October 1, 2005; 54(10): 3021 - 3025. [Abstract] [Full Text] [PDF]

				N. Abate, M. Chandalia, P. Satija, B. Adams-Huet, S. M. Grundy, S. Sandeep, V. Radha, R. Deepa, and V. Mohan ENPP1/PC-1 K121Q Polymorphism and Genetic Susceptibility to Type 2 Diabetes Diabetes, April 1, 2005; 54(4): 1207 - 1213. [Abstract] [Full Text] [PDF]

This Article Abstract Full Text (PDF) Submit a related Letter to the Editor Purchase Article View Shopping Cart Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kubaszek, A. Articles by Laakso, M. Search for Related Content PubMed PubMed Citation Articles by Kubaszek, A. Articles by Laakso, M.