Raised monocyte chemotactic protein-1 (MCP-1)/CCL2 in cerebrospinal fluid of patients with neuropsychiatric lupus

BACKGROUND

An imbalance in cytokine homoeostasis is thought to have a key role in the neuropsychiatric syndromes of systemic lupus erythematosus (NPSLE), and recently, a role for chemokines has been noted.

OBJECTIVE

To compare concentrations of monocyte chemotactic protein-1 (MCP-1)/CCL2 in cerebral spinal fluid (CSF) of patients with SLE, and with and without neuropsychiatric symptoms.

METHODS

CSF was obtained from 185 patients with SLE: 96 with NPSLE and 89 patients with SLE without neuropsychiatric symptoms (non-NPSLE patients). MCP-1/CCL2 concentrations were measured with an ELISA.

RESULTS

The average concentration of CSF MCP-1/CCL2 in patients with NPSLE was 1959 pg/ml, and in non-NPSLE patients 712 pg/ml. The average MCP-1/CCL2 concentration was significantly higher in the NPSLE group than in the non-NPSLE group (p<0.001). In one representative patient with NPSLE, MCP-1/CCL2 levels in the CSF decreased in parallel with a decline in neuropsychiatric symptoms.

CONCLUSIONS

CSF MCP-1/CCL2 levels are higher in patients with NPSLE than in non-NPSLE patients. MCP-1/CCL2 may have an important role in the expression of NPSLE. These results indicate that CSF MCP-1/CCL2 reflects an inflammatory activity in the brain, suggesting that it might be used as a diagnostic tool and a monitor for therapeutic responses in patients with NPSLE.

Interleukin 6, adiponectin, leptin, and insulin resistance in nonobese Japanese type 2 diabetic patients

The aim of the present study was to investigate the relationships between interleukin 6 (IL-6) and insulin resistance, serum leptin, serum adiponectin, or serum lipids including triglycerides in 98 nonobese Japanese type 2 diabetic patients. Insulin resistance was estimated by the insulin resistance index of homeostasis model assessment (HOMA-IR). Serum IL-6 concentration was negatively correlated to high-density lipoprotein cholesterol (r = -0.295, P = .004), but was not associated with HOMA-IR (r = 0.016, P = .871), body mass index (BMI) (r = 0.090, P = .375), systolic (r = 0.169, P = .116) and diastolic (r = -0.061, P = .570) blood pressures, leptin (r = 0.062, P = .544), and adiponectin (r = -0.020, P = .841) in these patients. In contrast, serum leptin level was positively correlated to HOMA-IR (r = 0.291, P = .004), BMI (r = 0.338, P < .001), and systolic blood pressure (r = 0.241, P = .025). Serum adiponectin level was negatively correlated to HOMA-IR (r = -0.288, P = .005), BMI (r = -0.308, P = .002), diastolic blood pressure (r = -0.269, P = .012), and triglycerides (r = -0.338, P < .001), and positively correlated to high-density lipoprotein cholesterol (r = 0.300, P = .003) in our patients. From these results, it can be suggested that fasting serum IL-6 is not a major factor responsible for the evolution of insulin resistance in nonobese Japanese type 2 diabetic patients.

Factors responsible for deteriorating glucose tolerance in newly diagnosed type 2 diabetes in Japanese men

Hyperglycemia frequently continues to worsen even after the diagnosis of overt diabetes. The aim of this study is to evaluate the factors contributing to increasing glucose intolerance after onset of type 2 diabetes in Japanese subjects. Five hundred fifty newly diagnosed type 2 diabetic patients were classified into 3 degrees of hyperglycemia based on plasma glucose levels estimated by 75-g oral glucose tolerance test: diabetes mellitus with isolated fasting hyperglycemia (DM/IFH), DM with isolated postchallenge hyperglycemia (DM/IPH), and DM with fasting and postchallenge hyperglycemia (DM/FPH). In addition, the DM/IFH and DM/IPH groups were subdivided to clarify the determinants of fasting and postchallenge hyperglycemia. Insulin secretion was evaluated by insulinogenic index, and insulin sensitivity was evaluated by composite index of insulin sensitivity (ISI composite). The insulinogenic index in DM/IFH was highest of the 3 groups (P < .0001). The insulinogenic index in DM/IPH was higher than in DM/FPH (P < .0001). The international sensitivity index composite in DM/IPH was highest of the 3 groups (P < .05). Although impaired early-phase insulin secretion plays the crucial role in deterioration from DM/IFH to DM/FPH in Japanese subjects, impaired early-phase insulin secretion and decreased insulin sensitivity both are factors in deterioration from DM/IPH to DM/FPH. In addition, comparison of subgroups of DM/IFH and DM/IPH shows that although decreased early-phase insulin secretion plays the more significant role in postchallenge hyperglycemia in Japanese subjects, insulin sensitivity is the more important factor in fasting hyperglycemia.

Three measures of tumor necrosis factor alpha activity and insulin resistance in nonobese Japanese type 2 diabetic patients

The aim of the present study was to investigate the relationship between insulin resistance and tumor necrosis factor alpha (TNF-alpha) as well as soluble TNF receptors (sTNF-R), body mass index (BMI), leptin, adiponectin, and serum lipid profile including triglycerides in nonobese Japanese patients with type 2 diabetes. A total of 88 nonobese Japanese type 2 diabetic patients were studied. The duration of diabetes was 11.0 +/- 0.8 years. In conjunction with BMI, glycosylated hemoglobin (HbA1c), fasting concentrations of plasma glucose, serum lipids (triglycerides, high-density lipoprotein cholesterol, and total cholesterol), serum leptin, serum adiponectin, serum TNF-alpha, and soluble TNF receptors (sTNF-R1 and sTNF-R2) were also measured. Insulin resistance was estimated by the insulin resistance index of homeostasis model assessment. Insulin resistance was positively correlated with BMI, triglycerides, leptin, and total cholesterol and negatively correlated with adiponectin and high-density lipoprotein cholesterol. In contrast, insulin resistance was not associated with TNF-alpha, nor sTNF-R (sTNF-R1 and sTNF-R2) in our diabetic patients. There was no significant relationship between the 3 measures of TNF-alpha system (TNF-alpha, sTNF-R1, and sTNF-R2) and BMI, serum triglycerides, leptin, or adiponectin in these patients. From these results, it can be concluded that peripheral levels of TNF-alpha system activity are not a major factor responsible for insulin resistance in nonobese Japanese type 2 diabetic patients.

Insulin secretion and insulin sensitivity in Japanese subjects with impaired fasting glucose and isolated fasting hyperglycemia

Impaired fasting glucose (IFG) is a subgroup of impaired glucose regulation exhibiting an elevated fasting glucose levels without elevated 2-h glucose levels on oral glucose tolerance test (OGTT). Diabetes mellitus with isolated fasting hyperglycemia (DM/IFH) is a similar subgroup of diabetes having higher fasting glucose levels with 2-h glucose levels within the non-diabetic range. The aim of this study is to profile the characteristics of these subgroups to estimate the factors involved in the development from normal glucose tolerance (NGT) via IFG to DM/IFH. Five hundred and sixty seven Japanese males were classified on the basis of 75 g OGTT into four groups, NGT, IFG, DM/IFH, and isolated impaired glucose tolerance (isolated IGT). Insulin secretion was evaluated by insulinogenic index, insulin sensitivity was evaluated by ISI composite, and insulin secretory patterns were compared additionally. IFG and DM/IFH subjects exhibited both lower insulin secretion and lower insulin sensitivity than NGT subjects. There was an insulin peak in NGT, IFG, and DM/IFH at 60 min, which did not occur in isolated IGT. Impaired early-phase and basal insulin secretion and decreased insulin sensitivity both are estimated as factors in progression from NGT via IFG to DM/IFH in these subjects. IFG and DM/IFH subjects have definite fasting hyperglycemia in contrast to isolated IGT subjects, 2-h glucose levels being maintained within the non-diabetic range partly by the insulin peak at 60 min.

Soluble TNF receptors and albuminuria in non-obese Japanese type 2 diabetic patients

The aim of this study was to investigate the relationships between albuminuria and tumor necrosis factor (TNF)-alpha or soluble TNF receptors (sTNF-R1, sTNF-R2) in eighty-eight non-obese Japanese type 2 diabetic patients stratified into two groups according to albuminuria status-microalbuminuria or normoalbuminuria. Patients with microalbuminuria were older and had significantly higher concentrations of sTNF-R1 and sTNF-R2 than those with normoalbuminuria. There was, however, no significant difference in sex, diabetes duration, smoking, BMI, systolic and diastolic blood pressure, HbA (1c), serum creatinine, and lipid profile between the two groups. Although serum TNF-alpha was positively correlated to serum sTNF-R1 and sTNF-R2, serum TNF-alpha level did not differ with respect to albuminuria. Univariate regression analysis showed that urinary albumin concentration was positively correlated to age (r=0.380, p<0.001), serum creatinine (r=0.214, p<0.05) and concentrations of sTNF-R1 (r=0.364, p<0.001) and sTNF-R2 (r=0.342, p<0.005). Other variables, including TNF-alpha, were not associated with albuminuria. Multiple regression analyses showed that urinary albumin concentration was independently predicted by the level of sTNF-R1 (F=32.1), which explained 26.3% of the variability of urinary albumin concentration. From these results, it can be concluded that serum soluble TNF receptor is an important independent factor associated with albuminuria in non-obese Japanese type 2 diabetic patients.

Single nucleotide polymorphisms in the gene encoding the major histocompatibility complex class II transactivator (CIITA) in systemic lupus erythematosus

BACKGROUND

The major histocompatibility complex (MHC) class II transactivator (CIITA) is a master switch of antigen presentation and activates expression of the MHC II gene. Insufficient up regulation of MHC class II molecules is reported to be one of the major immunological mechanisms in systemic lupus erythematosus (SLE).

OBJECTIVE

To examine the association between single nucleotide polymorphisms (SNPs) in the human CIITA gene (MHC2TA) and SLE.

METHODS

Promoters and coding regions of MHC2TA were evaluated for polymorphisms in 100 patients with SLE and 100 healthy donors. Eight oligonucleotide primer sets that covered the coding region and each promoter region were used for genomic analysis of SNPs.

RESULTS

Allele frequencies of previously reported SNPs did not differ between healthy donors and patients with SLE. Additionally, a new polymorphism in an intronic region at nt 485 (A-->A/G) was identified, which is close to the polymorphism at nt 474 that has been associated with one of the disease causing CIITA cDNA mutations in bare lymphocyte syndrome. This SNP was found in 11% of patients with SLE and in 3% of healthy donors, suggesting it may have a role in the pathogenesis of SLE.

CONCLUSIONS

A newly identified polymorphism in an intronic region at nt 485 (A-->A/G) may have an important role in the pathogenesis of SLE.

Preparation of a liquid nitrogen target for measurement of γ-rays in the 14N(, )15N reaction as an intensity standard in energy regions up to 11MeV

We have developed a liquid nitrogen (N(2)) target that allows us to clearly measure gamma-rays below 2 MeV and to improve neutron beam availability. The intensity of the prompt 2223 keV gamma-ray from the (1)H(n, gamma) reaction in the present target could be reduced to about 160 in comparison with the one in the commercially available melamine (C(3)H(6)N(6)) target. The statistics of the full-energy-peak counts were improved by factors of 15-30 and about 4 in the energy regions below and above 2 MeV, respectively.

Soluble E-selectin, leptin, triglycerides, and insulin resistance in nonobese Japanese type 2 diabetic patients

The aim of the present study was to investigate the relationships between insulin resistance and soluble E-selectin, body mass index (BMI), leptin, and serum lipid profile including triglycerides in nonobese Japanese type 2 diabetic patients. A total of 97 nonobese Japanese type 2 diabetic patients aged 43 to 84 years were examined. The duration of diabetes was 11.2 +/- 0.8 years. In conjunction with BMI and fasting concentrations of plasma glucose, serum lipids (triglycerides, total cholesterol, and high-density lipoprotein cholesterol) and serum insulin, soluble E-selectin, and leptin were also measured. The low-density lipoprotein (LDL) cholesterol level was calculated using the Friedewald formula. Insulin resistance was estimated by the homeostasis model assessment. The subjects were divided into 2 groups according to the value of insulin resistance estimated by the homeostasis model assessment. Values greater than 2.5 were indicative of the insulin-resistant state, and values less than 2.5 were indicative of the insulin-sensitive state. The insulin-resistant group had significantly higher levels of E-selectin, leptin, triglycerides, total and LDL cholesterol, and diastolic blood pressure as compared with the insulin-sensitive group. There was, however, no significant difference in age, sex, diabetes duration, BMI, systolic blood pressure, HbA1c, and high-density lipoprotein cholesterol between the 2 groups. Univariate regression analysis showed that insulin resistance was positively correlated to E-selectin (r = 0.305, P = .003), BMI (r = 0.283, P = .006), leptin (r = 0.296, P = .004), HbA1c (r = 0.241, P = .018), serum triglycerides (r = 0.385, P < .001), serum total (r = 0.240, P = .019) and LDL cholesterol (r = 0.254, P = .013) levels, and systolic (r = 0.247, P = .024) and diastolic (r = 0.305, P = .006) blood pressure. Multiple regression analyses showed that insulin resistance was independently predicted by serum E-selectin (F = 18.4), serum leptin (F = 14.0) and serum triglycerides (F = 20.0) levels, which explained 45.0% of the variability of insulin resistance. From these results, it can be concluded that in conjunction with serum triglycerides and serum leptin, serum E-selectin is another important independent factor associated with insulin resistance in nonobese Japanese type 2 diabetic patients.

High remnant lipoprotein levels in patients with variant angina

BACKGROUND

Dyslipidemia with increased oxidative stress but without elevation of low-density lipoprotein cholesterol has been recently implicated in the pathogenesis of coronary vasospasm.

HYPOTHESIS

Disordered triglyceride-rich lipoprotein metabolism may be linked to the genesis of coronary artery spasm.

METHODS

Both serum remnant lipoprotein (RLP) and alpha-tocopherol levels were determined in 18 patients with the active stage of variant angina (VA), in 16 patients with the inactive stage of variant angina (IVA), and in 19 control subjects (CONTROL).

RESULTS

The RLP levels were significantly (p < 0.05) higher in VA (6.4 +/- 2.7 mg/dl) than in IVA (4.4 +/- 1.5 mg/dl). In contrast, alpha-tocopherol levels were significantly lower in VA than that in CONTROL. Serum trigyceride levels were not significantly different among the study groups, although serum high-density lipoprotein cholesterol levels were significantly lower in VA than in CONTROL. Smoking was significantly (p < 0.05) more prevalent in VA (72%) than in IVA (25%) and CONTROL (37%). Serum RLP levels correlated positively with triglyceride levels (R = 0.73) and correlated inversely with alpha-tocopherol levels (R = -0.31) significantly in all study subjects.

CONCLUSIONS

Patients with active stage of variant angina had higher RLP levels than inactive patients with variant angina and lower alpha-tocopherol levels than control subjects. Disordered triglyceride-rich lipoprotein metabolism with increased oxidative stress appears to be linked to the activity of coronary vasospasm, suggesting a possible role in its pathogenesis.

Insulin secretion and insulin sensitivity at different stages of glucose tolerance: a cross-sectional study of Japanese type 2 diabetes

To evaluate the factors causing glucose intolerance in type 2 diabetes in Japan, insulin secretion and insulin sensitivity were compared across the range of glucose tolerance. Subjects were divided into 3 groups: normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and type 2 diabetes (DM) according to the criteria of the World Health Organization (WHO). We examined insulin secretion and insulin sensitivity using fasting blood glucose and insulin levels and 75 g oral glucose tolerance test (OGTT). We used homeostasis model assessment (HOMA) beta-cell and insulinogenic index (30 minutes) to estimate insulin secretion and HOMA-insulin resistance (IR) and insulin sensitivity index (ISI) composite for insulin sensitivity. Although insulin resistance plays an important role in the development of diabetes in many ethnic populations, the differences in insulin sensitivity between NGT and IGT and between IGT and DM are small in Japanese patients. On the other hand, as glucose intolerance increases, insulin secretion decreases most remarkably both between NGT and IGT and between IGT and DM in Japanese patients. Decreasing insulin secretion and decreasing insulin sensitivity both occur in developing type 2 diabetes in Japanese patients, but decreased basal and early-phase insulin secretion had more pronounced contribution to glucose tolerance than the indices of insulin sensitivity. Japanese type 2 diabetic patients are characterized by a larger decrease in insulin secretion and show less attribution of insulin resistance.

Bridging a 30-mm nerve defect using collagen filaments

This article describes a 30-mm regeneration of severed peripheral nerve axons along collagen filaments. Two thousand or 4000 31-mm-long collagen filaments were grafted to bridge a 30-mm defect of the rat sciatic nerve. A collagen tube was grafted as a control. The mean number and mean fiber diameter of regenerated myelinated axons were 330 +/- 227 and 2.7 +/- 0.9 microm in the distal end of the 2000 collagen-filaments nerve guide, and 564 +/- 275 and 2.5 +/- 1.1 microm in the distal end of the 4000 collagen-filaments nerve guide at 12 weeks postoperatively, whereas in the distal end of the collagen tube, no regenerated axon was found. These results suggest that the collagen filaments guide axons of the rat's sciatic nerve to regenerate for 30 mm and act as a scaffold for axonal regeneration. Thirty-millimeter nerve regeneration of a 1-mm-diameter rat sciatic nerve by an artificial nerve guarantees a clinical application of the implant which should be very important for patients and surgeons.

IGT with fasting hyperglycemia is more strongly associated with microalbuminuria than IGT without fasting hyperglycemia

Previous studies have established that impaired glucose tolerance (IGT) patients with fasting hyperglycemia (IGT/FH: fasting plasma glucose (FPG) level 6.1-7.0 mmol/l and 2 h PG level of 7.8-11.1 mmol/l) exhibit higher insulin resistance than those with isolated IGT (FPG level <6.1 mmol/l and 2 h PG level of 7.8-11.1 mmol/l), but the association with microalbuminuria has not been determined. Here, we evaluate the prevalence of microalbuminuria in non-diabetic Japanese males 20-70 years of age. The subjects were classified into four groups based on the results of OGTT: normal glucose tolerance (NGT: n=71), impaired fasting glucose (IFG: n=24), isolated IGT (n=36), and IGT/FH (n=23). A urinary albumin-to-creatinine ratio (ACR) from 30 to 300 microg/mg creatinine was counted as microalbuminuria. The prevalence of microalbuminuria was higher in subjects with IGT/FH than in subjects with isolated IGT (26% versus 14%). Logistic regression analysis showed microalbuminuria to be more significantly associated with IGT/FH (OR=3.82, 95% CI 1.09-13.36) than with isolated IGT (OR=1.75, 95% CI 0.50-6.17). While insulin resistance (HOMA-IR) in isolated IGT was not significantly different from that in NGT, insulin resistance in IGT/FH was significantly higher (P<0.01). Regression analysis of ACR in IGT showed a significant correlation with insulin resistance (P=0.012). Accordingly, microalbuminuria is more strongly associated with IGT/FH than with isolated IGT, most likely due to the higher insulin resistance.

Pharmacogenetics of disease-modifying anti-rheumatic drugs

The outcome of treatment with disease-modifying anti-rheumatic drugs (DMARDs) in rheumatoid arthritis (RA) patients is considerably variable and is also unpredictable. It would be useful clinically if physicians were able to predict responses to DMARDs prior to their administration. One possible cause of differences in efficacy and adverse drug reactions is genetic variation in how individuals metabolize drugs. Based on pharmacogenetics, tailor-made drug therapy, also called personalized drug therapy or individual drug therapy, will be possible with analysis of genetic polymorphism, such as single nucleotide polymorphism (SNP), and analysis of haplotype and diplotype configuration. Several studies of the correlation between the genetic polymorphism of enzymes metabolizing several DMARDs and efficacy or adverse drug reactions have already been reported, suggesting that pharmacogenetics will be applicable to the treatment of RA in the near future.

Prevalence of periodontal bacterial infection in non-obese Japanese type 2 diabetic patients: relationship with C-reactive protein and albuminuria

The aim of the present study was to investigate the relationship between periodontal bacteria infection ( Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Prevotella intermedius) and C-reactive protein (CRP) and albuminuria in non-obese Japanese type 2 diabetic patients. One hundred and thirty-four non-obese Japanese type 2 diabetic patients without evidence of current acute illness including clinically significant acute infectious disease were enrolled into the study. The degree of periodontal bacterial infection was evaluated using IgG titer against Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, or Prevotella intermedius. The bacterial sonic extracts were used as antigens. High-sensitivity CRP (hCRP), glucose, glycosylated hemoglobin (HbA (1c)), and lipids were also measured after an overnight fast. Urinary albumin excretion rate as a ratio of urinary albumin and urinary creatinine was assessed in a morning spot urine sample using a commercial enzymatic immunoassay. The prevalence of Porphyromonas gingivalis infection was 52.2 % and that of Actinobacillus actinomycetemcomitans and Prevotella intermedius was 7.5 and 14.2 %, respectively. IgG titer against Porphyromonas gingivalis significantly correlated with CRP (r = 0.225, p < 0.001) and albuminuria (r = 0.185, p < 0.05), while IgG titer against Actinobacillus actinomycetemcomitans or Prevotella intermedius was not associated with either parameter. These results suggest that among periodontal bacteria, Porphyromonas gingivalis infection is associated with atherosclerosis in non-obese Japanese type 2 diabetic patients.

Restoration of function after spinal cord transection using a collagen bridge

The restoration of function of transected adult mammalian spinal cord without living tissue has not been reported previously. We report the first success of functional restoration of transected spinal cord without living tissue. We grafted collagen filaments parallel or transverse to the axis of the spinal cord to bridge 5-mm defects of 47 adult rat spinal cords. Twenty-five rats were used as a control. Of the 72 rats, 42 rats survived the experimental period. At 4 weeks postoperatively, regenerated axons crossed the proximal and distal spinal cord-implant interfaces in all 5 rats of the parallel-grafted group. At 12 weeks postoperatively, the rats in the parallel-grafted group (8 rats) could walk, run, and climb with hind-forelimb coordination. The somatosensory-evoked potentials were seen. Results suggest that the collagen filaments support the axonal regeneration of the transected spinal cord and the restoration of function when grafted parallel to the axis of the spinal cord. The functional restoration appeared to be permanent, raising the possibility of therapeutic application in humans.

Bridging a spinal cord defect using collagen filament

STUDY DESIGN

A rat model of spinal cord defect was designed to evaluate the effect of collagen filament implant on nerve regeneration in the spinal cord defect.

OBJECTIVES

To bridge a spinal cord defect and restore the function in adult mammals.

SUMMARY OF BACKGROUND DATA

Resection of the spinal cord in mammals is always followed by motor paralysis and loss of voluntary function below the lesion. Partial success in bridging the ends of the spinal cord after complete resection was reported. However, restoration of function has not been reported in adult mammalian.

MATERIALS AND METHODS

Four thousand collagen filaments 5-mm-long were grafted to bridge a 5-mm defect of rat spinal cord. Controls had their spinal cord defect left ungrafted after resection. At 1-week intervals, animals were evaluated functionally. After 4 and 12 weeks, animals were evaluated histologically. After 12 weeks, animals were evaluated electrophysiologically.

RESULTS

The severed spinal cord axons regenerated along the collagen filament implant crossing the proximal and distal spinal cord implant interfaces at 4 weeks after surgery. The rats with collagen filament grafts could walk, run, and climb with hind forelimb coordination at 12 weeks after surgery. Sensory-evoked potential waveform was found in the rats with collagen filament at 12 weeks after surgery.

CONCLUSIONS

The collagen filaments support the axonal regeneration of the transected spinal cord and the restoration of function.

Platelet count is independently associated with insulin resistance in non-obese Japanese type 2 diabetic patients

The aim of the present study was to investigate the relationship between platelet count and insulin resistance in non-obese Japanese type 2 diabetic patients. A total of 163 non-obese Japanese type 2 diabetic patients (112 men and 51 women, aged 36 to 84 years, body mass index [BMI] 16.2 to 26.9 kg/m(2)) were studied. In conjunction with BMI, glycosylated hemoglobin (HbA(1c)), fasting concentrations of plasma glucose and serum lipids (triglycerides, low-density lipoprotein [LDL] cholesterol, high-density lipoprotein [HDL] cholesterol, and total cholesterol), and hematological parameters (platelets, white blood cell count, red blood cell count, hematocrit, hemoglobin) were measured. LDL cholesterol was calculated using the Friedewald formula. Insulin resistance was estimated by the insulin resistance index of homeostasis model assessment (HOMA-IR). Univariate regression analysis showed that HOMA-IR was positively correlated to BMI (r = 0.465, P <.0001), HbA(1c) (r = 0.423, P <.0001), platelet count (r = 0.310, P <.0001), triglycerides (r = 0.277, P <.0005), white blood cell count (r =.222, P =.005), red blood cell count (r = 0.210, P =.008), hematocrit (r = 0.156, P =.047), total cholesterol (r = 0.178, P =.023), and systolic (r = 0.216, P =.011) and diastolic (r = 0.263, P =.002) blood pressure, and inversely correlated to HDL cholesterol (r = -0.312, P <.0001) level in our diabetic patients. Multiple regression analysis showed that HOMA-IR was independently predicted by BMI (P <.0001, F = 22.45), HbA(1c) (P <.0001, F = 16.15), platelet count (P <.0001, F = 10.75), and serum triglycerides (P <.0001, F = 10.47) levels, which explained 34% of the variability of HOMA-IR in non-obese Japanese type 2 diabetic patients. These results indicate that not only BMI, HbA(1c), and triglycerides levels but also platelet counts are independent predictor of insulin resistance in non-obese Japanese type 2 diabetic patients.

Hypoadiponectinemia is associated with visceral fat accumulation and insulin resistance in Japanese men with type 2 diabetes mellitus

The aim of the present study was to investigate the association of serum adiponectin concentration with regional adiposity and insulin resistance in subjects with type 2 diabetes mellitus. A total of 73 Japanese men with type 2 diabetes (aged 59 +/- 11 years and body mass index [BMI] 23.8 +/- 3.0 kg/m(2), mean +/- SD) were studied. Fasting serum adiponectin and leptin concentrations were determined by radioimmunoassay. Regional adiposity was measured by abdominal computed tomography (CT) at the umbilical level, and insulin resistance was estimated by homeostasis model assessment (HOMA-R). Univariate regression analysis showed that serum adiponectin levels were negatively correlated with subcutaneous and visceral fat areas. With multivariate regression analysis, visceral fat area was a predominant determinant of serum adiponectin levels. In contrast, subcutaneous fat area was strongly associated with serum leptin concentrations. Among subcutaneous and visceral fat areas, BMI, and serum leptin levels, both subcutaneous and visceral fat areas were independently associated with HOMA-R. In another model incorporating serum adiponectin levels, serum adiponectin levels were selected as an independent determinant of HOMA-R instead of visceral fat area. In conclusion, hypoadiponectinemia was associated with visceral fat accumulation rather than subcutaneous fat depot in Japanese men with type 2 diabetes mellitus. Both subcutaneous and visceral fat accumulation contribute to insulin resistance in these subjects, and the contribution of visceral fat may be mediated, in part, by hypoadiponectinemia.

Factors responsible for development from normal glucose tolerance to isolated postchallenge hyperglycemia

OBJECTIVE

Isolated postchallenge hyperglycemia (IPH), defined as fasting plasma glucose (FPG) level <7.0 mmol/l and 2-h plasma glucose (PG) level >/=11.1 mmol/l, is a subtype of early-stage diabetes. This study evaluates the metabolic profiles of insulin secretion and insulin sensitivity in IPH to clarify the factors responsible for development of this form of type 2 diabetes.

RESEARCH DESIGN AND METHODS

We conducted cross-sectional analysis of 231 Japanese men aged 20-70 years. The subjects were classified into the following three groups, based on the results of a 75-g oral glucose tolerance test (OGTT): 1) normal glucose tolerance (NGT), defined as FPG level <6.1 mmol/l and 2-h PG level <7.8 mmol/l (n = 89); 2) impaired glucose tolerance (IGT), defined as FPG level <7.0 mmol/l and 2-h PG level of 7.8-11.1 mmol/l (n = 94); and 3) IPH (n = 48). We compared the three groups for insulin secretion (insulinogenic index) and insulin sensitivity (index of insulin resistance using homeostasis model assessment [HOMA-IR]).

RESULTS

The insulinogenic index in IPH was the lowest of the three groups (P < 0.001 versus NGT). The HOMA-IR in the IGT and IPH groups were significantly higher than in the NGT group (P < 0.001), but both were similar. By linear regression analysis, the insulinogenic index rather than fasting insulin or HOMA-IR was the more significant factor in the 2-h PG level in IGT and IPH.

CONCLUSIONS

Subjects with IPH exhibited distinctly impaired early-phase insulin secretion and only mild insulin resistance, indicating that reduced insulin secretion is the primary determinant of deterioration from NGT to IGT and IPH in development of type 2 diabetes in these subjects.

Relationship of regional adiposity to serum leptin level in nonobese Japanese type 2 diabetic male patients

BACKGROUND

The aim of the present study was to investigate the relationships between serum leptin levels and regional adipose fat area, BMI, and the measures of variables including serum insulin in nonobese Japanese type 2 diabetic patients.

METHODS

A total of 121 nonobese Japanese type 2 diabetic patients [aged 35 to 83 years, body mass index (BMI) (15.4 to 26.8 kg/m(2))] were studied. They all were male patients. In conjunction with serum leptin level, BMI, glycosylated hemoglobin (HbA(1c)), and fasting concentrations of plasma glucose and serum insulin and lipids (triglycerides, total and HDL cholesterol) were measured.

RESULTS

Univariate regression analysis showed that serum leptin levels were positively correlated to subcutaneous (r=0.566, P<0.0001) and visceral (r=0.481, P<0.001) fat area in our diabetic patients. Furthermore, serum leptin levels were positively correlated to serum insulin (r=0.517, P<0.0001), BMI (r=0.428, P<0.0001), serum triglycerides (r=0.279, P<0.005), and age (r=0.225, P<0.05). There was, however, no relationship between serum leptin levels and measures of other variables including total and HDL cholesterol. Multiple regression analyses showed that serum leptin levels were predicted by subcutaneous fat area (F=5.92, P<0.0001) and serum insulin level (F=5.60, P<0.0001), which explained 29.0% of the variability of serum leptin concentrations in our nonobese Japanese type 2 diabetic male patients. Visceral fat area, BMI, serum triglycerides, and age, however, were not independently associated with serum leptin levels in our patients.

CONCLUSIONS

These results indicate that serum leptin levels are reflective of subcutaneous fat area in nonobese Japanese type 2 diabetic male patients.