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OBJECTIVE—To classify type 1 diabetic females with bulimia nervosa (BN) by type of inappropriate compensatory behavior in order to prevent weight gain (ICB) and to investigate the group differences. RESEACH DESIGN AND METHODS—Type 1 diabetic females with BN, diagnosed by structured diagnostic interview based on DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th ed.) criteria, were classified by type of ICB as follows: 1) only severe insulin omission as an ICB (BN-I) (n = 22), 2) both severe insulin omission and self-induced vomiting and/or laxative abuse (BN-IP) (n = 22), or 3) no insulin omission but another ICB (BN-NI) (n = 11). The clinical characteristics of these three groups and a binge-eating disorder (BED) group (n = 24) were compared. RESULTS—The BN-IP and BN-I groups had the highest HbA1c levels. The BN-IP group had the highest rates of diabetic neuropathy, retinopathy, and nephropathy. The BN-NI group had the second highest rates of neuropathy and retinopathy. The BN-IP group had the highest frequencies of diabetes- and ketoacidosis-related hospital admissions, and the BN-I group had the second highest frequencies. The BN-NI group showed the highest scores on psychological tests related to depression, anxiety, eating disorder psychopathology, and perfectionism. The BN-NI group had the highest rate of history of visits to a psychiatrist, and the BN-IP group had the second highest history. CONCLUSIONS—Type 1 diabetic females with BN seem not to be homogenous and can be classified into three distinctive subgroups by type of ICB. Individuals with BN-IP had the most severe problems with both medical and psychological/behavioral aspects. Individuals with BN-NI manifested the highest psychological distress. The BN-I group had comparatively mild distress despite having the poorest metabolic control. Each BN group manifested more severe pathology than the BED group.

Advanced glycation end product (AGE) engagement of a cell surface receptor for AGE (RAGE) has been implicated in the development of diabetic complications. In this study, we determined the RAGE mRNA levels in monocytes from type 1 diabetic patients and analyzed their relationship with diabetic vascular complications. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis revealed that the monocyte expression of RAGE mRNA was significantly lower in patients with retinopathy than in those without retinopathy and was also significantly down-regulated in patients with nephropathy in comparison with those without nephropathy. Experiments with monocyte-enriched cultures revealed that RAGE mRNA and protein levels were down-regulated by the exposure to glyceraldehyde-derived AGE-the recently identified high-affinity RAGE ligand. Accordingly, we then assayed for the serum levels of glyceraldehyde-derived AGE as well as those of carboxymethyllysine (CML)-the known RAGE ligand and related them to the monocyte levels of RAGE mRNA. This screen revealed a negative correlation between the two parameters. The results thus suggest that the decrease in monocyte RAGE expression can be at least partly accounted for by the ligand engagement and may be a factor contributing to the development of diabetic vascular complications.

Spontaneously hypertensive rats (SHR) are the most extensively used animal model for genetic hypertension, increased stroke damage, and insulin resistance syndromes; however, the identification of target genes has proved difficult. SHR show elevated sympathetic nerve activity, and stimulation of the central blood pressure control centers with glutamate or nicotine results in exaggerated blood pressure responses, effects that appear to be genetically determined. Kynurenic acid, a competitive glutamate antagonist and a non-competitive nicotinic antagonist, can be synthesized in the brain by the enzyme kynurenine aminotransferase-1 (KAT-1). We have previously shown that KAT-1 activity is significantly reduced in SHR compared with normotensive Wistar Kyoto rats (WKY). Here we show that KAT-1 contains a missense mutation, E61G, in all the strains of SHR examined but not in any of the WKY or outbred strains. Previous studies on F2 rats from a cross of stroke-prone SHR and WKY have shown a suggestive level of linkage between elevated blood pressure and the KAT-1 locus on chromosome 3. In addition, the mutant enzyme expressed in Escherichia coli displays altered kinetics. This mutation may explain the enhanced sensitivity to glutamate and nicotine seen in SHR that may be related to an underlying mechanism of hypertension and increased sensitivity to stroke.

Bioactivity of Insulin-like growth factors (IGEs) are positively or negatively regulated by IGF binding proteins (IGFBPs). Like IGFs, production of IGFBPs are influenced by a number of hormonal factors. We studied the effects of cytokines on production of IGFBPs in human fibroblasts in culture. Both IL-1beta and TNF-alpha inhibited IGFBP-3 (42/38 KDa species) production in a concentration dependent manner judged by Western ligand blot. Expression of IGFBP-3 mRNA was also decreased by these cytokines. Moreover, the treatment with IL-1beta and TNF-alpha resulted in appearance of smaller mol weight (26 KDa) immunoreactive IGFBP-3 fragment(s) which lacked the ability to bind 125I-IGFs, indicating that these cytokines degrade IGFBP-3 via activation of proteases. Both IL-1beta and TNF-alpha decreased production of IGFBP-4, whereas they increased that of IGFBP-6, IL-6 had little effect on production of IGFBPs. Likewise, interferon-gamma failed to affect of production of IGFBPs except at high concentrations. The present data demonstrate that cytokines, especially IL-1beta and TNF-alpha are potent regulators of IGFBPs production and degradation. These cytokines may alter tissue uptake of IGFs and help to counteract the catabolic state induced by them.

Beta 3-adrenergic receptors are expressed mainly in adipose tissues and play an important role in lipolysis and thermogenesis. Chronic administration of beta 3-adrenergic receptor agonists into obese rodents reduce the size of adipocytes by the breakdown of triglyceride and ameliorate insulin resistance associated with the normalization of the expression of adipocytokines, such as leptin and tumor necrosis factor-alpha. However, acute administration of the drugs induce remarkable insulin secretion, the mechanism of which is still unclear. Although the effect of beta 3-adrenergic receptor agonists may be different between rodents and human, these drugs are promising as anti-obese or anti-diabetic agents, and several clinical studies are underway.

To assess the use of fasting plasma glucose (FPG) alone for the screening of diabetes as defined by a 2-h plasma glucose (2-h PG) > or =11.1 mmol/l following a 75-g oral glucose tolerance test, we collated the results from 17512 subjects aged 30-89 years without a previous history of diabetes from 12 general population-based Asian studies. The performance of FPG corresponding to the 2-h PG > or =11.1 mmol/l was characterized. The prevalence of diabetes was 4.0% by the FPG criteria only and 6.0% by the 2-h PG criteria only. The FPG value of 7.0 mmol/l gave a sensitivity for diabetes as defined by a 2-h PG > or =11.1 mmol/l of 46% and specificity of 99%. The FPG associated with a 2-h PG > or =11.1 mmol/l with optimal sensitivity and specificity was 5.8 mmol/l (sensitivity 79%, specificity 85%). The optimal FPG cut-point was affected by gender, age, body mass index and the presence of hypertension, and the resulting sensitivity and specificity corresponding to each optimal cut-point changed. The FPG was a specific but insensitive screening test for diabetes defined by 2-h PG > or =11.1 mmol/l. There seems to be ethnic differences with respect to optimal FPG cut-point, and different screening strategies may be necessary in different parts of the world.

In 1995, the Japan Diabetes Society (JDS) appointed the Committee for the Classification and Diagnosis of Diabetes Mellitus. The Committee presented a final report in May 1999 in Japanese. This is the English version with minor modifications for readers outside Japan. Concept of diabetes mellitus: Diabetes mellitus represents a group of diseases of heterogeneous etiology, characterized by chronic hyperglycemia and other metabolic abnormalities, which are due to deficiency of insulin effect. After a long duration of metabolic derangement, specific complications of diabetes (retinopathy, nephropathy, and neuropathy) may occur. Arteriosclerosis is also accelerated. Depending on the severity of the metabolic abnormality, diabetes may be asymptomatic, or may be associated with symptoms (thirst, polyuria, and weight loss), or may progress to ketoacidosis and coma. Classification ( cf. Tables 1 and 2 and Fig. 1) : Both etiological classification and staging of pathophysiology by the degree of deficiency of insulin effect need to be considered. The etiological classification of diabetes and related disorders of glycemia includes, (1) type 1; (2) type 2; (3) those due to specific mechanisms and diseases; and (4) gestational diabetes mellitus. Type 1 is characterized by destructive lesions of pancreatic β cells either by an autoimmune mechanism or of unknown cause. Type 2 diabetes is characterized by combinations of decreased insulin secretion and decreased insulin sensitivity (insulin resistance). Category (3) includes two subgroups; subgroup A is diabetes in which specific mutations have been identified as a cause of genetic susceptibility, while subgroup B is diabetes associated with other pathologic conditions or diseases. The staging of glucose metabolism includes normal, borderline and diabetic stages. The diabetic stage is further classified into three substages; non-insulin requiring, insulin-requiring for glycemic control, and insulin-dependent (ID) for survival. In each individual, these stages may vary according to the deterioration or the improvement of the metabolic state, either spontaneously or by treatment. Diagnosis ( cf. Tables 3 and 4) : The confirmation of chronic hyperglycemia is a prerequisite for the diagnosis of diabetes mellitus. The state of glycemia may be classified within three categories, diabetic type; borderline type; and normal type. Diabetic type is defined when fasting plasma glucose (FPG) is 7.0 mmol/l (126 mg/dl) or higher, and/or plasma glucose 2 h after 75 g glucose load (2hPG) is 11.1 mmol/l (200 mg/dl) or higher. A casual plasma glucose (PG) ≥11.1 mmol/l (200 mg/dl) also indicates diabetic type. Normal type is defined when FPG is below 6.1 mmol/l (110 mg/dl) and 2hPG below 7.8 mmol/l (140 mg/dl). Borderline type includes those who are neither diabetic nor normal types. These cutoff values are for venous PG measurements. The persistence of ‘diabetic type' in a subject indicates that he or she has diabetes. For children, a dose of 1.75 g/kg (maximum, 75 g) is used for oral glucose tolerance test (OGTT). The procedure for clinical diagnosis is as follows. 1Diabetes mellitus is diagnosed when hyperglycemia meeting the criteria for ‘diabetic type' is shown on two or more occasions examined on separate days. 2Diabetes can be diagnosed by a single PG test of ‘diabetic type' if one of the following three conditions co-exists, (1) typical symptoms of diabetes mellitus; (2) HbA 1c ≥6.5% by a standardized method; or (3) unequivocal diabetic retinopathy. 3If the above conditions ((1) or (2)) have been present in the past and well documented, the subject is diagnosed either to have diabetes or to be suspected of diabetes, even if the present level of glycemia does not reach that of ‘diabetic type'. 4If the diagnosis of diabetes cannot be established by these procedures, re-testing of PG is recommended after an appropriate interval. 5The physician should assess not only the presence or absence of diabetes, but also its etiology and glycemic stage, and the presence and absence of diabetic complications or associated conditions. Epidemiological aspects and screening: In order to determine the prevalence of diabetes in a population, ‘diabetic type' may be regarded as ‘diabetes'. The use of 2hPG cutoff level of ≥11.1 mmol/l (200 mg/dl) is recommended. If this is difficult, the FPG cutoff level of ≥7.0 mmol/l (126 mg/dl) can be used, but is likely to lead to under-ascertainment. For screening, the most important point is not to overlook ‘diabetes'. In addition to parameters of hyperglycemia, clinical information such as family history, obesity etc., should be regarded as indications for further testing. Normal type and borderline type: Only FPG and 2hPG are adopted as cutoff values, but in clinical situations, it is recommended to measure PG also at 30 and 60 min during 75 g OGTT. Among people with normal type, those with 1hPG higher than 10.0 mmol/l (180 mg/dl) are at higher risk to develop diabetes than those with lower 1hPG. When OGTT is performed, the borderline type corresponds to the sum of impaired fasting glycemia (IFG) plus impaired glucose tolerance (IGT) according to the new WHO report. Subjects in this category are at higher risk of developing diabetes than those with ‘normal type'. Those with low insulinogenic index (the ratio of increment of plasma insulin to that of PG at 30 min during OGTT) are at particularly high risk to develop diabetes. Microvascular complications are rare but arteriosclerotic complications are fairly frequent in this category. Gestational diabetes mellitus ( GDM ) : The current definition of GDM is ‘ any glucose intolerance developed or detected during pregnancy'. We adopt the proposal of the Japan Society of Gynecology and Obstetrics for the diagnosis of GDM (1984). GDM is defined when two or more values during a 75 g OGTT are higher than the following cutoff levels; FPG ≥5.5 mmol/l (100 mg/dl), 1hPG ≥10.0 mmol/l (180 mg/dl) and 2hPG ≥8.3 mmol/l (150 mg/dl). As a screening test, subjects with casual PG ≥5.5 mmol/l (100 mg/dl) are recommended for further testing. Patients who have had documented glucose intolerance before pregnancy, and who present as ‘diabetic type' should be under closer supervision than those who develop GDM during pregnancy for the first time. HbA 1c : There is a large overlap in the distribution of HbA 1c between groups with ‘normal type' and ‘borderline type' and mild ‘diabetic type'. Therefore, HbA 1c is not a suitable parameter to detect mild glucose intolerance. HbA 1c higher than 6.5% suggests diabetes, but HbA 1c below 6.5% alone should not be taken as evidence against the diagnosis of diabetes. Comparison with reports of American Diabetes Association ( ADA ) in 1997 and WHO in 1999: The present report is unique in the following points when compared with those of the ADA ‘Diabetes Care 20 (1997) 1183' and WHO ‘Report of a WHO Consultation (1999)'. (1) Diabetes due to specific mechanisms and diseases is divided into two subgroups; diabetes in which genetic susceptibility is clarified at the DNA level and diabetes associated with other diseases or conditions. (2) Cutoff PG levels are the same as those of ADA and WHO, but a term ‘type' is added to each glycemic category, because a single coding of ‘diabetic type' hyperglycemia does not define diabetes. Diabetes is diagnosed when ‘diabetic type' hyperglycemia is shown on two or more occasions. (3) A single ‘diabetic type' hyperglycemia is considered sufficient for the diagnosis of diabetes, if the patient has typical symptoms, HbA 1c ≥6.5%, or diabetic retinopathy. (4) OGTT is recommended for those with mild hyperglycemia, because FPG criteria alone would overlook many subjects with ‘diabetic type' in Japan. High 1hPG without elevation of FPG and 2hPG is also considered to be a risk factor for future diabetes. (5) Borderline type in the present report corresponds to the sum of IFG and IGT by WHO when OGTT is performed. (6) New criteria for GDM by OGTT are proposed.

Hyperinsulinemia has been shown to be associated with diabetic angiopathy. Migration and proliferation of vascular smooth muscle cells (VSMC) are the processes required for the development of atherosclerosis. In this study, we attempted to determine whether insulin affects mitogenic signaling induced by plateletderived growth factor (PDGF) in a rat VSMC cell line (A10 cells). PDGF stimulated DNA synthesis which was totally dependent on Ras, because transfection of dominant negative Ras resulted in complete loss of PDGF-stimulated DNA synthesis. Initiation of DNA synthesis was preceded by activation of Raf-1, MEK and MAP kinases (Erk 1 and Erk2). Treatment of the cells with PD98059, an inhibitor of MAPK kinase (MEK) attenuated but did not abolish PDGF-stimulated DNA synthesis, suggesting that MAPK is required but not essential for DNA synthesis. PDGF also stimulated phosphorylation of protein kinase B (Akt/PKB) and p70 S6Kinase (p70S6K) in a wortmannin-sensitive manner. Rapamycin, an inhibitor of p70S6K, markedly suppressed DNA synthesis. Low concentrations of insulin (1-10 nmol/l) alone showed little mitogenic activity and no significant effect on MAPK activity. However, the presence of insulin enhanced both DNA synthesis and MAPK activation by PDGF. The enhancing effect of insulin was not seen in cells treated with PD98059. Insulin was without effect on PDGF-stimulated activations of protein kinase B (Akt/PKB) and p70S6K. We conclude that insulin, at pathophysiologically relevant concentrations, potentiates the PDGFstimulated DNA synthesis, at least in part, by potentiating activation of the MAPK cascade. These results are consistent with the notion that hyperinsulinemia is a risk factor for the development of atherosclerosis.

Several lines of evidence suggest that ATP-sensitive potassium (KATP) channels are involved in glucose uptake by insulin target tissues. The aim of the present study was to prove directly the effect of KATP channel activity on glucose transport into cultured human skeletal muscle cells. We used potassium channel openers PCO-400 and nicorandil alone or in combination with channel blockers glibenclamide and gliclazide to examine their effects on insulin- or high glucose concentration-induced glucose uptake using 2-deoxy-D-3H-glucose or 3-O-methyl-D-3H- glucose as tracer, respectively. PCO-400 inhibited the basal (non-stimulated) uptake of 2-DG or 3-OMG at the glucose concentration of 5mM. PCO-400 and nicorandil dose-dependently inhibited insulin-stimulated glucose uptake, and their inhibitory effects were reversed by glibenclamide or gliclazide. In addition, PCO-400 inhibited high glucose concentration-facilitated glucose transport in the absence of insulin, and this effect was also antagonized by both sulfonylurea drugs. Regarding the mechanism by which KATP channels modulate glucose transport, we focused on protein kinase C (PKC), because PKC has been supposed to participate in both insulin- and high glucose concentration -stimulated glucose transport. PMA (phorbol 12-myristate 13-acetate) dose-dependently reversed the PCO-400-induced suppression of insulin-stimulated glucose uptake. On the other hand, PCO-400 at the concentration that inhibited glucose uptake caused no alteration of membrane-associated PKC activity in the presence of insulin or PMA. From these results we conclude that KATP channels modulate the basal and insulin-or high glucose level-stimulated glucose transport in skeletal muscle through a mechanism independent of PKC.

Troglitazone is effective in approximately 50% in patients with type 2 diabetes (NIDDM). In this study, we investigated the relations between serum leptin levels and clinical efficacy of troglitazone. Forty-five type 2 diabetic patients (23 men and 22 women) from our outpatient clinic were treated with troglitazone 400 mg daily for 12 weeks. Fasting plasma glucose (FPG), HbA1c, body weight, serum insulin and leptin concentrations were measured before and after troglitazone treatment. After 12 weeks of troglitazone treatment, FPG (before versus after, 179+/-33 vs. 138+/-26 mg/dl, mean+/-SD), HbA1c (7.8+/-1.3 vs. 6.9+/-1.0%), IRI (8.3+/-4.3 vs. 6.3+/-3.4 microU/ml) and HOMA-R index (homeostasis model assessment of insulin resistance) (3.8+/-2.4 vs. 2.2+/-1.3) decreased significantly, while body mass index (BMI) slightly increased (26.3+/-3.5 vs. 26.6+/- 3.6 kg/m(2)), and serum leptin remained unchanged (8.5+/-7.2 vs. 9.1+/-8.7 ng/ml). Reduction in FPG (DeltaFPG) after troglitazone treatment were correlated with reduction in HOMA-R (DeltaHOMA-R) (r=0.721, P

Deposition of hyaluronan has been implicated in the pathogenesis of diabetic glomerulosclerosis. We hypothesized the involvement of hyaluronan in diabetic tubulointerstitial fibrosis. We investigated high-glucose effect on hyaluronan production by rat renal interstitial fibroblasts (normal rat kidney [NRK] cells) and examined the role of hyaluronan in NRK cell proliferation. The involvement of protein kinase C (PKC) and transforming growth factor-[beta ] (TGF-[beta ]) in this response was also examined. After 24 hours of incubation in medium containing 25.6 mmol/L glucose, production of hyaluronan by NRK cells was significantly increased compared with medium containing 5.6 mmol/L glucose ( P [lt ] .01). L -glucose and mannitol had no effect on hyaluronan production. High glucose enhanced basal in situ PKC activity ( P [lt ] .01), and both an activator of PKC (phorbol 12-myristate 13-acetate; [PMA]) and TGF-[beta ] 1 were able to increase hyaluronan production by NRK cells ( P [lt ] .01). The effect of high glucose on hyaluronan production was diminished by coincubating cells with PKC inhibitors (staurosporine [Stp] or calphostin C [CpC]) or with an anti-TGF-[beta ] neutralizing antibody. Stimulation of hyaluronan production by PMA was also normalized by anti TGF[beta ] neutralizing antibody, but the effect of TGF-[beta ]1 was not affected by inhibition of PKC. Finally, incubating quiescent NRK cells with 50 or 100 ng/mL hyaluronan for 24 hours significantly increased NRK cell number ( P [lt ] .01). In conclusion, high glucose stimulates hyaluronan production through the PKC/TGF-[beta ] cascade. Increased hyaluronan promotes NRK cell proliferation. These results suggest that hyaluronan may play a role in the pathogenesis of interstitial fibrosis in diabetic kidney disease.

Mutations in transcription factors that play a role in the development of the endocrine pancreas, such as insulin promoter factor-1 and NeuroD1/BETA2, have been associated with diabetes. Cell type–specific members of the basic helix-loop-helix (bHLH) family of transcription factors play essential roles in the development and maintenance of many differentiated cell types, including pancreatic β-cells. Neurogenin 3 is a bHLH transcription factor that is expressed in the developing central nervous system and the embryonic pancreas. Mice lacking this transcription factor fail to develop any islet endocrine cells and die postnatally from diabetes. Because neurogenin 3 is required for the development of β-cells and other pancreatic islet cell types, we considered it a candidate diabetes gene. We screened the coding region of the human neurogenin 3 gene (NEUROG3) for mutations in a group of unrelated Japanese subjects with maturity-onset diabetes of the young (MODY). We found three sequence variants: a deletion of 2-bp in the 5′-untranslated region (NEUROG3-g.-44–45delCA), a G-to-A substitution in codon 167 (g.499G/A), resulting in a Gly-to-Arg replacement (G/R167), and a T-to-C substitution in codon 199 (g.596T/C), resulting in a Phe/Ser polymorphism F/S199. These polymorphisms were not associated with MODY, thereby suggesting that mutations in NEUROG3 are not a common cause of MODY in Japanese patients.

To investigate the contribution of the liver to whole-body insulin resistance in patients with type 2 diabetes mellitus, we analyzed the early decline (slope "a") in the baseline plasma glucose level following acute hyperinsulinemia in the initial phase of a euglycemic hyperinsulinemic clamp study, rather than using an isotope-dilution method. Slope "a" was comparable among groups of diabetic and non-diabetic subjects, and did not correlate well with glucose infusion rate (GIR), an index of peripheral (primarily skeletal muscle) insulin resistance. In contrast, slope "a" was significantly lower in obese (BMI25) type 2 diabetic patients compared with their non-obese counterparts, consistent with the general belief that obesity is a condition of insulin resistance in liver as well as in peripheral tissues. A subset of six insulin-resistant (nearly zero GIR) type 2 diabetic patients (pubertal adolescents) demonstrated a markedly blunted slope "a". Their insulin resistance (GIR) substantially recovered concomitant with an increase in slope "a" after pretreatment with somatostatin analogue in two cases studied, suggesting possible suppression of hepatic glucose production through lowering of plasma glucagon concentrations. Furthermore, slope "a" correlated significantly (r = -0.480, p0.0001) with HOMA index (FPG x FIRI), the latter being recently regarded as an index of hepatic insulin resistance. These data showed that slope "a" obtained from euglycemic hyperinsulinemic clamp may be a clinically useful index of hepatic insulin resistance rather than an index of peripheral insulin resistance.

Aims/hypothesis. Mutations in the transcription factor hepatocyte nuclear factor (HNF)-4α are the cause of one form of maturity-onset diabetes of the young, MODY1. The HNF-4γ is structurally related to HNF-4α and is expressed together with HNF-4α in pancreatic islets. We therefore tested the hypothesis that genetic variation in the HNF-4γ gene (HNF4G) is associated with MODY in Japanese subjects. Methods. We screened the protein coding region of HNF4G (exons 3–11) for mutations in 57 unrelated Japanese subjects with MODY by amplifying each exon and adjacent intron region using the polymerase chain reaction (PCR) and specific primers and then directly sequencing the PCR products. The frequency of each variant was compared between patients with MODY and a group of non-diabetic subjects. Results. We found ten sequence variants, two of these were located in exons: exon 6, a silent substitution in codon 144, c.432A/G and exon 7, a G-to-A substitution in codon 190 (c.570G/A) resulting in a conservative Met-to-Ile substitution (M/I190) in the putative ligand-binding region of HNF-4γ protein. The remaining eight variants were located in introns. There was no significant difference in the frequency of these polymorphisms between subjects with MODY and non-diabetic control subjects. Conclusion/interpretation. Genetic variation in the coding region of HNF4G is unlikely to be a major cause of MODY in Japanese people. [Diabetologia (2000) 43: 1064–1069]

OBJECTIVE: Serum triglyceride levels are important in the development of atherosclerosis. Although triglyceride levels are generally increased in the postprandial periods, the association between postprandial triglyceride (pTG) levels and atherosclerosis has not been investigated in diabetic patients. To investigate the role of pTG levels in atherosclerosis, we examined the correlation between pTG levels and carotid intimal-medial thickness (IMT). RESEARCH DESIGN AND METHODS: Carotid IMT was measured by ultrasonography in 61 patients with type 2 diabetes. Plasma glucose (PG), insulin, total cholesterol, triglycerides, and HDL cholesterol levels were measured after overnight fasting and 4 h after a meal. RESULTS: Carotid IMT of the patients with fasting hypertriglyceridemia was greater than that of the patients with normal fasting triglyceride (fTG) levels (0.85+/-0.12 vs. 0.76+/-0.14 mm; P = 0.02). The carotid IMT was increased in the patients with pTG levels >2.27 mmol/l. The normo-normo (NN) and normo-hyper (NH) groups consisted of patients with normal fTG levels but with pTG levels 2.27 mmol/l, respectively. Patients with both hypertriglyceridemia and pTG levels >2.27 mmol/l formed the hyper-hyper (HH) group. Carotid IMT was significantly increased in the NH (0.86+/-0.13 mm) and HH (0.85+/-0.12 mm) groups compared with the NN group (0.73+/-0.13 mm; P

Mutations in the transcription factors hepatocyte nuclear factor (HNF)-4alpha and -1alpha, insulin promoter factor-1, and HNF-1beta are the causes of four forms of maturity-onset diabetes of the young (MODY1 and 3-5, respectively). The winged-helix transcription factor HNF-3beta has been implicated in the regulation of expression of each of these MODY genes, suggesting that mutations in the HNF-3beta gene (HNF3B) may also cause MODY. We have tested this hypothesis by screening a panel of 57 unrelated Japanese subjects with a clinical diagnosis of MODY for mutations in HNF3B. This analysis revealed four frequent polymorphisms that were not associated with MODY, including one in the promoter region (-213A/G), two silent mutations in the codons for Ala 97 (291C/T) and Gly 279 (837A/G), and one in the 3'-untranslated region (1424C/T). Two rare substitutions in the 5'-untranslated region, -156C/T and -67A/C, were found in a heterozygous state in two subjects, and two subjects were heterozygous for putative missense mutations, S109N (326G > A) and A328V (983C>T). The two missense mutations were not found in 106 normal chromosomes from nondiabetic subjects. It was not possible to test for co-segregation of these mutations with diabetes and thus, it is unclear whether or not these mutations can cause MODY. The results of our study suggest that mutations in HNF3B are not a common cause of MODY in Japanese subjects.

Although most of patients with non-insulin-dependent diabetes mellitus (NIDDM) have insulin resistance, it is unknown whether a molecule might interfere with insulin action. Membrane glycoprotein PC-1 (plasma cell antigen-1), which inhibits insulin receptor tyrosine kinase activity, was isolated from fibroblasts of NIDDM patients. Because PC-1 content in skeletal muscle and adipose tissue correlated with whole body insulin sensitivity, PC-1 might play a role in insulin resistance. In order to know whether PC-1 activity of fibroblasts is also elevated in Japanese NIDDM patients, and whether PC-1 activity correlates with the parameters of insulin resistance in vivo or not, we measured PC-1 activity of cultured fibroblasts from 17 patients with NIDDM and seven healthy controls. PC-1 activity of the NIDDM patients was 85.2 +/- 33.1 nmol/mg per min (mean +/- S.D.), and was higher than that of healthy controls (42.6 +/- 12.7 nmol/mg per min, P = 0.0002). Insulin sensitivity was measured in 11 of 17 NIDDM patients by the artificial pancreas. PC-1 activity of the patients with insulin resistance (glucose infusion rate3.0 mg/kg per min, n = 7) was elevated to 99.9 +/- 31.9 nmol/mg per min, while that of the other patients (n = 4) was 55.3 +/- 7.5 nmol/mg per min (P = 0.003). In conclusion, glycoprotein PC-1 activity of dermal fibroblasts is correlated with insulin resistance in patients with NIDDM.

In a hospital cohort study, we examined whether or not ACE (Angiotensin-I converting enzyme) and AGT (Angiotensinogen) gene polymorphisms were associated with the development of nephropathy in long-term Japanese insulin-dependent diabetes mellitus (IDDM) patients with or without proliferative retinopathy, and whether or not the polymorphisms were associated with an arteriosclerotic family history in first degree relatives of the patients. A total of 201 patients with IDDM for more than 10 years and 159 patients with IDDM for more than 15 years were randomly selected in our hospital. All patients received uniform diabetes management and were divided into three groups, no nephropathy, incipient nephropathy and clinical nephropathy groups. There were no differences in clinical characteristics excluding urinary albumin to creatinine ratio and systolic blood pressure between the three groups. ACE I/D polymorphism was related to plasma ACE activity, but there were no associations between ACE I/D polymorphism and the development of diabetic nephropathy, nor was renal deterioration observed in patients with proliferative retinopathy even in those with a history of diabetes for more than 15 years. The AGT polymorphism did not have an additive effect on the association between ACE polymorphism and the development of diabetic nephropathy in patients with or without retinopathy. Development of diabetic nephropathy in the patients with or without proliferative retinopathy did not result in ACE or AGT polymorphisms. On the other hand, the ACE DD genotype was associated with a family history of ischemic heart disease in first degree relatives (X2 score = 9.04, P < 0.05). ACE and AGT gene polymorphisms may not play a role in the protective or accelerative effect against the development of diabetic nephropathy in the patients with or without proliferative retinopathy, but ACE gene polymorphism might be related to an arteriosclerotic family history in Japanese IDDM patients.

To date, evidence for long-term renoprotection with angiotensin receptor blockers (ARBs) has come almost exclusively from Caucasian patients (1–3), despite Japanese people being at high risk of diabetic nephropathy and very susceptible to end-stage renal disease (4–6). We conducted the INNOVATION Study (Incipient to Overt: Angiotensin II Blocker, Telmisartan, Investigation on Type 2 Diabetic Nephropathy) to evaluate the efficacy of an ARB in preventing transition from microalbuminuria to overt nephropathy in Japanese patients (7). This study is the first large-scale clinical study to investigate prevention of overt diabetic nephropathy using an ARB in normotensive and hypertensive Japanese patients with type 2 diabetes. The randomized, multicenter, double-blind, placebo-controlled trial was performed in patients aged from 30 to 74 years with type 2 diabetes and urinary albumin-to-creatinine ratio (UACR) 100–300 mg/g and serum creatinine

Advanced glycation end products (AGEs) and receptor for AGE (RAGE)-mediated mechanism has been implicated in the pathogenesis of the vascular derangements.1–3 Yonekura et al recently identified a novel splice variant of RAGE that would serve as a decoy receptor, and named it endogenous secretory RAGE (esRAGE).4 esRAGE is secreted from expresser cells exemplified by vascular endothelial cells and is able to captures RAGE ligands extracellularly, thereby protecting cells from AGE-induced injury.4 Recently, we reported that type 1 diabetic patients with high serum esRAGE levels were resistant to developing early retinal complications than those with low esRAGE levels.5 Moreover, plasma esRAGE is found to be a novel biomarker and a potential protective factor in metabolic syndrome and atherosclerosis.6 It is thus expected that esRAGE plays a protective role in the development of diabetic vascular complications. The balance or imbalance between RAGE ligand and esRAGE levels may be a …

OBJECTIVE Heterozygous mutations in the transcription factors hepatocyte nuclear factor (HNF)-1α, HNF-1β, and HNF-4α are associated with maturity-onset diabetes of the young (MODY) and are believed to cause this form of diabetes by impairing pancreatic β-cell function. The HNFs also play a central role in the tissue-specific regulation of gene expression in liver and kidney, suggesting that patients with MODY due to a mutation in HNF-1α, HNF-1β, or HNF-4α may exhibit abnormal liver or kidney function. Here, we have examined liver and kidney function in a series of Japanese patients with HNF-4α/MODY1, HNF-1α/MODY3, and HNF-1β/MODY5 diabetes. RESEARCH DESIGN AND METHODS Clinical and biochemical data were obtained from Japanese subjects with HNF-1α, HNF-1β, and HNF-4α diabetes. The clinical data included information on BMI, age at diagnosis, current treatment, and the presence and nature of any complications. The biochemical studies examined liver and kidney function and included measures of alanine and aspartate aminotransferase, γ-glutamyl transpeptidase, blood urea nitrogen, creatinine, uric acid, total and HDL cholesterol, triglycerides, and 17 serum proteins. RESULTS The present age and duration of diabetes were similar in patients with HNF-1α, HNF-1β, or HNF-4α diabetes, as was the age at diagnosis of diabetes in the youngest generation. All subjects were lean. Of the subjects with HNF-1α and HNF-4α diabetes, 50% were treated with insulin, as were all three subjects with HNF-1β diabetes. Retinopathy was present in patients with each form of diabetes. None of the subjects with HNF-4α diabetes had evidence of nephropathy, whereas 36% of the patients with HNF-1α diabetes and 100% of those with HNF-1α diabetes showed diminished kidney function. The three subjects with HNF-1β diabetes also had abnormally high serum creatinine, uric acid, and blood urea nitrogen levels, which are consistent with impaired kidney function, and one of seven subjects with HNF-1α diabetes had a mild elevation in creatinine and blood urea nitrogen levels. These values were within the normal range in the three patients with HNF-4α diabetes. Although the HNFs play a role in regulating the expression of the genes for most, if not all, serum proteins, there was no decrease in the levels of any of the 17 serum proteins examined, and most were within or slightly above the normal range. Lipoprotein(a) [Lp(a)] levels were elevated in the three patients with HNF-4α diabetes and in one patient with HNF-1β diabetes, and in a second patient with HNF-1β diabetes, Lp(a) was at the upper limit of normal. CONCLUSIONS The results indicate that as in white patients, MODY resulting from mutations in the HNF-1α, HNF-1β, and HNF-4α genes in Japanese patients may be a severe disease similar to classic type 2 diabetes. In addition, they suggest that patients with HNF-1β diabetes may be characterized by diminished kidney function and perhaps abnormal liver function. Further studies are needed to determine whether tests of liver and kidney function will be useful in the diagnosis and subclassification of MODY.

Disproportional hyperproinsulinemia is a sensitive marker for beta-cell dysfunction. The objective of this study was to assess the proinsulin profile in persons with insulin-dependent diabetes mellitus (IDDM) after pancreas-kidney transplantation. We determined serum insulin, C-peptide, and proinsulin concentrations during an oral glucose challenge in five pancreas-kidney transplant recipients, nine nondiabetic kidney transplant recipients, and 17 normal subjects. Basal proinsulin concentrations were significantly increased in pancreas-kidney recipients (geometric mean [+/-1 SE range], 6.0 [5.5 to 6.4] pmol/L) and kidney recipients (6.4 [5.4 to 7.5] pmol/L) compared with the normal subjects (2.8 [2.5 to 3.2] pmol/L). Integrated proinsulin concentrations during the oral glucose load were also higher in pancreas-kidney recipients (1.4 [1.1 to 1.8] nmol/L x min) and kidney recipients (1.5 [1.2 to 2.0] nmol/L x min) versus normal subjects (0.8 [0.7 to 0.9] nmol/L x min). There was no difference in basal or integrated proinsulin concentrations between the two transplant groups. Even after adjustment for the glomerular filtration rate (GFR), basal and incremental proinsulin concentrations continued to be higher in the transplant groups than in the normal subjects. Proinsulin to C-peptide molar ratios both before and after the glucose load were similar in the three groups. From these findings, we conclude that pancreas-kidney transplantation provokes proportional hyperproinsulinemia, which is closely associated with its reduced clearance in the kidneys.

A 34-year-old female IDDM patient complained of chest oppression in hypoglycemic episodes and electrocardiograms revealed reversible ischemic changes occuring concomitantly with hypoglycemia. The ECG changes improved and the chest oppression disappeared following increasing blood glucose level by glucose intake. Master's double load test and treadmill load test were positive for ischemic changes. Radioisotopic myocardial scintigraphy by thallium and BMIPP did not show any filling defects and coronary angiography revealed no remarked stenosis in the coronary arteries. She had no mitochondrial tRNA Leu (A→G) gene mutation at nucleotide position 3243, but both the patient and her mother had a G-to-A transition within the replication origin of the light strand at nucleotide position 5744 of the mitochondrial gene. As the patient's maternal family had no history of ischemic heart disease, it is not clear whether mitochondrial gene mutation at nucleotide position 5744 reflects the occurence of cardiac ischemia. Some disorders of microcirculation in capillary vessels in cardiac muscles may occur in such patients.

A mitochondrial tRNALeu(UUR) mutation at nucleotide 3,243 is known to be found in most patients with MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes) and has also been identified in several families with maternally inherited diabetes mellitus and hearing loss. We report here audiologic features in patients with hearing loss associated with the mutation. Four patients without and five with MELAS were studied. Most of the patients had bilateral progressive sensorineural hearing loss. The most common shape of the audiogram was sloping, while cases in the advanced stages had flat audiograms. Speech discrimination scores were generally poor and did not parallel the degree of hearing loss. The present study suggests that the lesion for hearing loss could include both cochlear and retrocochlear involvement, but does not demonstrate a significant difference in the audiologic findings between patients with and without MELAS.

Tubulointerstitial damage plays a crucial role in the progression of kidney diseases, including diabetic nephropathy (1). Among several distinct types of fatty acid–binding protein (FABP), liver-type FABP (l-FABP) is abundantly expressed in hepatocytes and constitutively expressed in proximal tubular cells of the kidney (2). l-FABP incorporates albumin-bound free fatty acids (FFAs) that are filtered through the glomeruli into proximal tubular cells and transports FFAs from the cytosol to the nucleus (3). In transgenic mice expressing human l-FAPB, protein overload, resulting in massive proteinuria, upregulated renal l-FABP expression and increased its urinary excretion (4), suggesting that urinary l-FABP may reflect tubulointerstitial damage. Recently, in patients with nondiabetic glomerular disease, urinary excretion of l-FABP increased in parallel with the severity of tubulointerstitial injury and correlated with proteinuria and the rate of progression of renal disease, suggesting that l-FABP may be a useful indicator for the progression of nondiabetic kidney disease (4,5). To determine the clinical significance of l-FABP in patients with diabetic nephropathy, we conducted a cross-sectional study comparing urinary l-FABP excretion in diabetic patients with serial stages of kidney disease. Adult patients with type 2 diabetes were recruited from the outpatient clinic of the Division of Nephrology and Hypertension, Diabetes Center, Tokyo Women’s Medical University …

To evaluate the pancreatic amylin in the pathogenesis of non-insulin-dependent diabetes mellitus (NIDDM), we determined the pancreatic amylin (IRA) and insulin (IRI) contents of pancreata obtained at autopsy from diabetics and nondiabetics. IRA was extracted from the tail of the pancreas using formic acid and assayed with a human amylin kit. Following gel filtration of amylin on a Sephadex G-50 column, it was eluted in a similar fraction to insulin. The pancreatic IRA content was significantly higher (p0.01) in NIDDM subjects compared with nondiabetics, with the mean values being 4.25 +/- 1.62 and 0.085 +/- 0.022 microgram/g, respectively. The IRA content of two IDDM pancreata was low. No significant relationship was found between the IRA and the IRI contents or between the IRA content and the duration of diabetes. However, there was a tendency for the IRA content to increase in longstanding diabetes. Men had a significantly higher pancreatic IRA content than women. The four subjects with very high IRA levels (10 micrograms/g) were all elderly men with a long duration of diabetes. Thus, although the pancreatic amylin content was increased in NIDDM, no significant relationship to the clinical features of the disease was found.

We showed previously that the disproportionate elevation of serum proinsulin at fasting and after glucose ingestion in Type 2 diabetes is reduced to nearly normal after improvement of glycemic control by diet therapy. In this study, we investigated the effect of sulfonylurea (SU) treatment on serum proinsulin levels and proinsulin/insulin ratio (PI/I) during oral glucose tolerance test in patients with Type 2 diabetes. Thirteen diabetic patients (age 56 +/- 9 years, body mass index 22.4 +/- 1.9 kg/m2, mean +/- SD) were examined by 75 g oral glucose tolerance test (OGTT) before and after glycemic control by SU therapy. Mean interval of two OGTTs was 126 days. Serum proinsulin was measured by the radioimmunoassay using a human proinsulin-specific antiserum. When glycemic control improved after SU therapy (mean fasting plasma glucose 11.5 and 6.0 mmol/l, before and after SU treatment), fasting insulin, proinsulin and PI/I ratio did not change significantly. Insulin response during OGTT markedly increased after SU therapy. Summed value of insulin (sigma I) increased from 634 to 1064 pmol/l after SU (P < 0.01), whereas summed proinsulin (sigma PI) did not change significantly (146 and 159 pmol/l), resulting in a significant decrease in sigma PI/sigma I (23.6-15.1%, P < 0.05). We conclude that the disproportionate elevation of proinsulin during OGTT in patients with Type 2 diabetes can be reduced after glycemic control by SU treatment, chiefly by a selective increase in insulin response.

We studied a woman with acanthosis nigricans and insulin resistance. The patient's Epstein-Barr virus-transformed lymphocytes revealed slightly decreased insulin binding and markedly decreased insulin-stimulated autophosphorylation of the insulin receptor. The nucleotide sequence analysis of the patient's genomic DNA revealed a 3-basepair in-frame deletion in one allele, resulting in the loss of leucine at position 999 of the insulin receptor (delta Leu999). The messenger ribonucleic acid transcripts from the mutant allele in the patient's lymphocytes were not decreased. Insulin-stimulated autophosphorylation of the insulin receptor from cells expressing delta Leu999 mutant insulin receptor complementary DNA was markedly decreased. The proband, her mother, elder brother, and younger brother, who were heterozygous for this mutation, showed moderate or marked hyperinsulinemia during oral glucose tolerance tests. Although fasting glucose levels were normal and fasting insulin values were preserved in all subjects with the mutation for the 8-yr period of observation, a tendency of progressive increase in postload glucose levels was observed. These results suggest that the delta Leu999 mutation, which reduces tyrosine kinase activity, was responsible for insulin resistance and contributed to postload hyperglycemia.

Although the insulin gene region is implicated in susceptibility to Type 1 (insulin-dependent) diabetes mellitus in Caucasians, significance of this region to Type 1 diabetes in Japanese remains unclear because the class 1 alleles (shorter insertion) of the variable number of tandem repeat in the 5′ region of the insulin gene are predominant in both diabetic and nondiabetic subjects. The 5′ insulin gene polymorphism was analysed in 75 Japanese patients and 69 control subjects with a precise method using PvuII and a polymorphism specific probe, which enabled us to divide class 1 alleles into four subclasses. Allelic frequencies were not significantly different between Type 1 diabetic patients and control subjects. The polymorphism in the 3′ untranslated region of the insulin gene (1127/ PstI) was also analysed and found to be tightly linked to the 5′ insulin gene polymorphism, and thus was not associated with diabetes. Interaction between HLA-DR and the insulin gene region, which was reported in the French study, was not observed in Japanese. These results suggest that the insulin gene region is not a valuable genetic risk factor for Type 1 diabetes in Japanese.

When a patient is aged and osteoporotic, the collapse of the graft bone used in lumbar interbody fusion is a common problem [1] and occurs even if some type of spinal instrumentation such as a Zielke system or Steffee VSP plate is added. Before 1988, we performed posterior lumbar interbody fusion (PLIF), using only autograft with spinal instrumentation. Among 19 patients whose age was over 60.3 (16%) had graft bone collapse which resulted in pseudoarthrosis. Pain at the donor site is also a common complaint after surgery. To prevent these problems, we have used a hydroxyapatite (HA) block as the interbody spacer, and we will analyze the results here.

We reported that insulin sensitivity is inhibited by interruption of the hepatic parasympathetic reflex by surgical denervation of the liver or pharmacological blockade of the cholinergic neurotransmitter in rats (123). Therefore, we tested the hypothesis that parasympathetic neuropathy is associated with insulin resistance in type 2 diabetic patients. At the present time, only one method is available to directly measure autonomic nerve activity (4), and there are no methods available to measure hepatic parasympathetic nerve activity in humans. Thus, we used the deep breathing test to evaluate a cardiovascular parasympathetic nerve function. Hepatic parasympathetic neuropathy will often occur in parallel with cardiovascular parasympathetic neuropathy, because diabetic autonomic neuropathy is a systemic distal polyneuropathy. A total of 42 patients …

Intravenous fluorescein angiography has been widely used in evaluating diabetic retinopathy. Diabetic patients in whom fluorescein angiography is crucial are likely to have chronic kidney disease (CKD) because retinopathy and nephropathy usually progress in parallel. Although numerous reports have been published concerning the development of adverse reactions after fluorescein angiography (1–3), to the best of our knowledge, it has never been debated in the literature whether fluorescein (noniodinated contrast media) induces nephropathy as does iodinated radiocontrast. Therefore, we conducted this hospital-based retrospective cohort study to determine whether fluorescein angiography is associated with deterioration of renal function in diabetic patients with CKD. Among consecutive diabetic patients undergoing fluorescein angiography to assess retinopathy at the Department of Ophthalmology, …

Three families with abnormal insulinemia have been reported in Japan and sequencing analysis revealed that they had the same point mutation in one allele of the insulin genes causing [Leu A3]insulin. To estimate whether or not this same mutation came from a common ancestor we determined the sequence of the hypervariable region 5′-flanking the third [Leu A3]insulin allele (insulin Tochigi). This region is composed of 42 tandem repeating oligonucleotides, is 599 base pairs long and the sequence is 5′ cdi jfa faa aba baa aaa fab aaa caa aac aca cba aaf ccb 3′ (abbreviated as a = ACAGGGGTGTGGGG; b = ACAGGGGTCTGGGG; c = ACAGGGGTCCTGGGG; d = ACAGGGGTCCGGGG; f = ACAGGGGTCCCGGGG; i = ACAGGGTCCTGGGG; j = ACAGGGGTGTGAGG). The length of this region is different from those of the first and second [Leu A3]insulin alleles (insulin Wakayama I,II). This difference suggests either that insulin Tochigi and insulin Wakayama I,II are not of the same origin, or that three cases of [Leu A3]insulin in Japan have the same ancestor but recombination has occurred in this region at some point in the past.

Oxidative stress has been demonstrated to play an essential role in the destruction of pancreatic β-cells without infiltrating inflammatory cells in mice with type 1 diabetes (1). Recently, it was reported that a nucleotide substitution in mitochondrial DNA, a C-to-A transversion at nucleotide position 5178 within the NADH dehydrogenase subunit 2 gene, resulting in a Leu→Met substitution (Mt5178A), is related to longevity and that individuals with Mt5178C are more susceptible to adult-onset diseases than those with Mt5178A (2). Mt5178C/A genotype may influence oxidative damage to mitochondrial DNA. Myers et al. (3) recently reported that the specific inhibition of mitochondrial oxidative phosphorylation induced hyperexpression of GAD in pancreatic β-cells. Inhibitors of NADH-ubiquinone …