Effect of nifedipine on adiponectin in hypertensive patients with type 2 diabetes mellitus.

Nifedipine, a dihydropyridine calcium antagonist, improves endothelial function in patients with hypercholesterolaemia by enhancing nitric oxide (NO) activity, and increases endothelial NO bioavailability by antioxidant mechanisms. We administered a long-acting nifedipine formulation (controlled release (CR) nifedipine: 20 mg/day) to hypertensive patients for 6 months. There were no other changes of drug treatment during therapy with CR nifedipine. Clinical and biochemical data obtained before and after CR nifedipine administration were compared. All markers were measured by enzyme-linked immunosorbant assay. The levels of soluble markers (soluble CD40 ligand, soluble P-selectin, and soluble E-selectin), microparticles (MP) (platelet-derived MP, monocyte-derived MP, and endothelial cell-derived MP), and adiponectin differed between the control group and the hypertension group. The levels of these markers were also different in hypertensive patients with and without type 2 diabetes compared with the control group. In the hypertensive patients with type 2 diabetes, all markers except adiponectin decreased significantly after 3 months of CR nifedipine treatment. In contrast, markers were unchanged in the hypertensive patients without type 2 diabetes. Adiponectin was increased after 6 months of CR nifedipine treatment in hypertensive patients with type 2 diabetes. The effects of CR nifedipine on platelet/monocyte activation and adiponectin levels demonstrated in the present study indicate the potential effectiveness of calcium antagonist therapy for hypertensive patients with type 2 diabetes.

Effects of pitavastatin on adiponectin in patients with hyperlipidemia.

The effects of treatment with pitavastatin on inflammatory and platelet activation markers and adiponectin in 117 patients with hyperlipidemia were investigated to determine whether pitavastatin may prevent the progression of atherosclerotic changes in hyperlipidemic patients. Adiponectin levels prior to pitavastatin treatment in hyperlipidemic patients with and without diabetes were lower than levels in normolipidemic controls. Both total cholesterol and the low-density lipoprotein cholesterol decreased significantly after pitavastatin administration. Additionally, hyperlipidemic patients with or without type 2 diabetes exhibited a significant increase in adiponectin levels 6 months after pitavastatin treatment (diabetes: 3.52 +/- 0.80 vs. 4.52 +/- 0.71 microg/ml, p < 0.001; no diabetes: 3.48 +/- 0.71 vs. 4.23 +/- 0.82 microg/ml, p < 0.05). However, high-sensitivity C-reactive protein, platelet-derived microparticle and soluble P-selectin did not exhibit any differences before or after pitavastatin administration. Levels of adiponectin significantly increased after pitavastatin administration in the group of lower soluble P-selectin (soluble P-selectin before pitavastatin treatment <200 ng/ml). These results suggest that pitavastatin possesses an adiponectin-increasing effect in patients with hyperlipidemia and this effect is influenced by intensive platelet activation.

Genetic analysis of HLA, NA and HPA typing in type 2 diabetes and ASO.

We examined the genetic status of human leucocyte antigens (HLA), human platelet alloantigens (HPA) and neutrophil-specific antigens (NA) in patients with type 2 diabetes mellitus and diabetic arteriosclerosis obliterans (ASO). To our knowledge, the present study is the first report showing the relationship among three genetic factors in type 2 diabetes mellitus and ASO patients. HLA typing was performed by the polymerase chain reaction (PCR)-restriction fragment length polymorphism method. HPA-typing and NA-typing were by a PCR-sequence-specific primer method. The incidence of HLA-DRB1*1501 was found to be significant in type 2 diabetes and non-diabetic, particularly ASO-positive patients, compared to control subjects. There were no differences in NA1/NA2 between the control and diabetic or non-diabetic ASO groups. However, the frequency of NA2/NA2 in ASO-positive diabetes and non-diabetic ASO patients was significantly higher than controls. The a/b genotype of HPA-5a/5b was significantly lower in type 2 diabetes and non-diabetic ASO-positive patients than in controls. These findings suggest that genetic studies of HLA, NA and HPA could be useful to understand the pathogenesis of type 2 diabetes and ASO.

Benidipine improves oxidized LDL-dependent monocyte and endothelial dysfunction in hypertensive patients with type 2 diabetes mellitus.

We investigated the effects of long-term benidipine treatment on levels of monocyte and endothelial cell activation markers in hypertensive patients with (n = 28) and without (n = 10) type 2 diabetes mellitus. Benidipine, 4 mg/day, was administered for 6 months; there were no other changes in any of the patients pharmacologic regimens during benidipine treatment. Clinical and biochemical data obtained before and after benidipine administration were compared; all markers were measured by ELISA. The levels of platelet activation markers (CD62P, CD63, and PAC-1), microparticles (monocyte-derived microparticles: MDMPs, and endothelial cell-derived microparticles: EDMPs), chemokines (monocyte chemotactic peptide 1: MCP-1, regulated on activation normally T-cell expressed and secreted: RANTES) and soluble adhesion markers (soluble E-selectin and soluble ICAM-1) differed in the control and hypertension groups. In addition, levels of platelet, monocyte, and endothelial cell activation markers, microparticles, chemokines, and soluble adhesion molecules were higher in hypertensive patients than in those without type 2 diabetes. Furthermore, benidipine administration decreased the concentrations of all these markers. The effect of this drug was significant in diabetes patients with high levels of antioxidized low-density lipoprotein (LDL) antibody. These results suggest that benidipine is effective for the treatment of oxLDL-dependent vascular disorders in hypertensive patients with type 2 diabetes.

Detection of monocyte-derived microparticles in patients with Type II diabetes mellitus.

AIMS/HYPOTHESIS: The role of plasma monocyte-derived microparticles (MDMPs) and platelet-activation markers (platelet-derived microparticle [PDMP], platelet-bound CD62P [plt-CD62P], and platelet-bound CD63 [plt-CD63]) in diabetic vascular complications is not clear. We measured and compared plasma concentrations of MDMPs and the platelet-activation markers to investigate their possible contribution to diabetic vascular complications. METHODS: Activated platelets and microparticles (PDMP and MDMP) were analysed by flow cytometry. Concentrations of serum sE-selectin were measured with enzyme-linked immunosorbent assay. RESULTS: The concentration of MDMPs in diabetic patients was higher than in normal subjects. We found no differences in the binding of anti-GPIIb/IIIa and anti-GPIb monoclonal antibodies between groups. There were differences, however, in the concentrations of PDMPs, plt-CD62P, and plt-CD63 between Type II (non-insulin-dependent) diabetes mellitus patients and control subjects (PDMPs: 585 +/- 25 vs 263 +/- 9, p < 0.01; plt-CD62P: 28.1 % +/- 1.4 % vs 9.4 % +/- 0.6 %, p < 0.001; plt-CD63: 28.1 % +/- 1.4 % vs 8.6 % +/- 0.5 %, p < 0.001). Amounts of MDMPs correlated positively with these platelet activation markers, and the relation between PDMP and MDMP was the most significant. The concentration of MDMP in patients who had diabetes complicated with nephropathy, retinopathy, or neuropathy was higher than in those without diabetes-related complications. The increase in MDMP was particularly significant in patients with nephropathy. Concentrations of sE-selectin were higher in Type II diabetes patients than in control subjects, and correlated with MDMP, PDMP, plt-CD62P, and plt-CD63 levels in nephropathy patients. CONCLUSION/INTERPRETATION: In Type II diabetes patients, we detected increased activation of monocytes, which could have been stimulated by activated platelets and PDMPs. Because the activation of monocytes is associated with vascular endothelial damage, high concentrations of MDMPs could indicate vascular complications in diabetes patients, especially those who have diabetes-related nephropathy.

Significance of chemokines and activated platelets in patients with diabetes.

Levels of platelet-derived microparticles (PMPs), platelet activation markers (P-selectin expressed on, or annexin V binding to, platelets (plt:P-selectin or plt:annexin V, respectively)), chemokines (IL-8, monocyte chemotactic peptide-1 (MCP-1), and regulated on activation normally T-cell expressed and secreted (RANTES)), and soluble P- and E-selectins were compared in peripheral blood from diabetic and control patients in order to develop a better understanding of their potential contribution to diabetic vascular complications. Significant increases were found for PMPs, plt:P-selectin, MCP-1, RANTES and soluble P- and E-selectins in diabetic individuals, whereas IL-8 levels were similar. Furthermore, after ticlopidine treatment, most of these factors receded to baseline levels observed in non-diabetic patients. Our findings indicate that ticlopidine might be able to prevent or reduce vascular complications in diabetic patients.

Effects of beraprost and cilostazol and renal function on serum thrombomodulin levels in diabetic patients.

Serum thrombomodulin (TM) levels were determined in diabetic patients, and the effects of diabetic complications and renal function on TM were studied. Serum TM levels increased in diabetics, and patients with diabetic nephropathy tended to manifest higher levels of TM. There was a significant correlation between TM and serum creatinine levels. In addition, there was a significant elevation in serum TM levels in diabetics over time (1 year to 1 year 8 months), and the changes were particularly evident in patients who had a higher TM level from before the observation period. Furthermore, when patients were treated with an antiplatelet agent--beraprost (CAS 88475-69-8) or cilostazol (CAS 73963-72-1)--a significant reduction in TM levels was observed after 3 months. It is suggested that TM could be used as index to assess the development of clinical complications in diabetics and that anti-platelet agents have potential usefulness in delaying the aggravation of diabetic complications.

Effect of sarpogrelate hydrochloride on platelet-derived microparticles and various soluble adhesion molecules in diabetes mellitus.

We measured platelet-derived microparticles, activated platelets, and various adhesion molecules in 48 patients with diabetes mellitus. We also performed a comparative study of these parameters before and after administration of sarpogrelate hydrochloride. The numbers of platelet-derived microparticles and activated platelets were increased significantly in diabetic patients, and CD63-positive platelets were increased in patients with diabetic complications and poorly controlled blood glucose. Soluble adhesion molecules and thrombomodulin were also increased significantly. After administration of sarpogrelate hydrochloride, not only CD62p- and CD63-positive platelets, but also platelet-derived microparticles were decreased significantly. Soluble adhesion molecules and thrombomodulin were also significantly decreased after the treatment. These data suggest that (a) in patients with diabetes, antiplatelet therapy with sarpogrelate hydrochloride is a useful antithrombin therapy because it suppresses the production of intrinsic coagulants by activated platelets; and (b) sarpogrelate hydrochloride decreases endothelial cell damage via adhesion molecules.

Serum concentration and renal handling of 1,5-anhydro-D-glucitol in patients with chronic renal failure.

We measured serum and urinary 1,5-anhydro-D-glucitol (1,5-AG) during a glucose tolerance test (GTT) in patients with chronic renal failure (CRF) and compared the fractional excretion of 1,5-AG (FEAG) with that of diabetes mellitus (DM) patients and healthy controls. The mean serum 1,5-AG in CRF patients [60 +/- 23(SE) mumol/L] was significantly lower than in controls (155 +/- 7 mumol/L) in spite of a normal glycaemia. The levels in the CRF group were similar to those in the DM group. During GTT, the blood glucose profile in the CRF group was not significantly different from that of the control group, and urinary glucose excretion was negligible. However, FEAG was significantly higher in CRF patients than in controls. These data suggest that serum 1,5-AG in patients with CRF decreases due to a decrease in 1,5-AG reabsorption, independently of glucose excretion, and that serum and/or urinary 1,5-AG can be a useful marker for renal tubular dysfunction because the 1,5-AG reabsorption system is more vulnerable than the glucose reabsorption system.

Measurement of serum leptin in patients with chronic renal failure on hemodialysis.

BACKGROUND: Leptin, the product of the obese gene, is produced exclusively in fat cells. SUBJECTS, MATERIALS AND METHODS: To evaluate the clinical significance of measuring serum leptin in 56 patients with chronic renal failure on hemodialysis (HD), we measured leptin levels using radioimmunoassay in 34 normal volunteers and in 56 patients on HD. RESULTS: Normal serum leptin averaged 5.7 +/- 0.7 (mean +/- SEM) ng/ml, which correlated significantly (p < 0.001) with the body fat percentage as measured by bioelectrical impedance analysis. Serum leptin in HD patients ranged from 1.3 to 142 ng/ml. The mean serum leptin analyzed after the logarithmic conversion was 5.6 ng/ml, which was not significantly different from the normal control value, although the body fat percentage was significantly lower than normal volunteers. There was a significant (p < 0.01) positive correlation between body fat percentage and serum leptin in both normal controls and HD patients. The slope of the regression curve was steeper in HD patients than in normal controls. CONCLUSION: (1) serum leptin levels to body fat mass are significantly higher in HD patients than controls; (2) the variability is much wider in HD patients; and (3) a significant relation exists between percent body fat and log serum leptin, the relation being steeper in HD patients than in controls.

Effect of treatment with 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors on serum coenzyme Q10 in diabetic patients.

Serum coenzyme Q10 (CoQ10: 2-(3,7,11,15,19,23,27,31,35,39-decamethyl-2,6,10,14,18,22,26,30,34 ,38 -tetracontadecaenyl)-5,6-dimethoxy-3-methyl-1,4-benzoquinone, CAS 303-98-0) and cholesterol levels were measured to assess the effect of cholesterol-lowering therapy in patients with non-insulin-dependent diabetes mellitus (NIDDM). Twenty healthy volunteers, 97 NIDDM patients and 2 patients with familial hypercholesterolemia were studied. None had overt heart failure or any other heart disease. Mean serum CoQ10 concentrations were significantly (p < 0.01) lower in diabetic patients with normal serum cholesterol concentrations, either with or without administration of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (HMG-CoA RIs) including simvastatin (normal: 0.91 +/- 0.26 (mean +/- SD) mumol 1(-1); diabetic with HMG-CoA RI: 0.63 +/- 0.19; diabetic without HMG-CoA RI: 0.66 +/- 0.21). CoQ10 concentrations were higher (1.37 +/- 0.48, p < 0.001) in diabetic patients with hypercholesterolemia. Simvastatin or low density lipoprotein apheresis decreased serum CoQ10 concentrations along with decreasing serum cholesterol. Oral CoQ10 supplementation in diabetic patients receiving HMG-CoA RI significantly (p < 0.001) increased serum CoQ10 from 0.81 +/- 0.24 to 1.47 +/- 0.44 mumol 1(-1), without affecting cholesterol levels. It significantly (p < 0.03) decreased cardiothoracic ratios from 51.4 +/- 5.1 to 49.2 +/- 4.7%. In conclusion, serum CoQ10 levels in NIDDM patients are decreased and may be associated with subclinical diabetic cardiomyopathy reversible by CoQ10 supplementation.

Significance of platelet-derived microparticles and activated platelets in diabetic nephropathy.

We measured levels of platelet-derived microparticles (PMP), which have coagulative activity and are produced by platelet activation or physical stimulation, and CD62P/CD63-positive platelets in patients with diabetes mellitus to determine their clinical significance and effects on complications of diabetes including diabetic nephropathy. We also compared these levels before and after administration of the antiplatelet drug cilostazol. Plasma PMP and CD62P/CD63-positive platelet levels were significantly higher in patients with diabetes mellitus than normal controls. CD62P-positive platelet levels were significantly higher in patients with nephropathy than in patients without complications. After administration of cilostazol, PMP and CD62P/CD63-positive platelet levels were significantly decreased. The increases in platelet activity and its related procoagulant activity appear to account in part for the hypercoagulability observed in diabetes mellitus. Our findings suggest that activated platelets might play a role in the development of diabetic nephropathy. Furthermore, antiplatelet therapy with cilostazol for diabetic patients may be useful as antithrombin therapy including antiplatelet therapy, since it suppresses the production of intrinsic coagulants produced by platelet activation.

Effect of cilostazol on soluble adhesion molecules and platelet-derived microparticles in patients with diabetes.

We evaluated the plasma concentrations of soluble adhesion molecules and platelet-derived microparticles (PMP) in patients with non-insulin dependent diabetes mellitus (NIDDM) and studied the effect of cilostazol on PMP generation. There were differences in the levels of soluble adhesion molecules between NIDDM patients (N = 43) and the control subjects (N = 30) (soluble thrombomodulin: 11.5+/-5.3 vs. 7.0+/-1.2 TU/ml, p<0.0001; soluble vascular cell adhesion molecule-1: 708+/-203 vs. 492+/-113 ng/dl, p<0.0001; soluble intercellular cell adhesion molecules- 1: 274+/-65 vs. 206+/-48 ng/dl, p<0.0001; soluble P-selectin: 194+/-85 vs. 125+/-43 ng/dl, p<0.0001). There were also differences in the levels of PMP and platelet activation markers between NIDDM patients and the controls (PMP: 943+/-504 vs. 488+/-219/10(4) plt, p<0.0001; platelet CD62P: 9.2+/-4.6 vs. 4.4+/-4.3%, p<0.001; platelet CD63: 10.2+/-4.5 vs. 4.5+/-3.3%, p<0.0001; platelet annexin V: 9.1+/-3.9 vs. 5.3+/-3.8%, p<0.001). To study the release of PMP into plasma, a modified cone-and-plate viscometer was used. Increased release of PMP from platelets was observed in diabetic plasma compared to normal plasma under high shear stress conditions (2,672+/-645 vs. 1,498+/-386/10(4) plt, p<0.05). Therefore, one cause of PMP elevation in NIDDM may be high shear stress. The levels of PMP, activated platelets, and soluble adhesion molecules all decreased significantly after treatment with cilostazol. These results suggest that cilostazol may be useful for the inhibition of both PMP-dependent and -independent vascular damage in NIDDM.

Histocompatibility antigens and polymyalgia rheumatica in a Japanese patient with insulin-dependent diabetes mellitus.

A 30-year-old Japanese female developed insulin-dependent diabetes mellitus (IDDM). She later complained of muscle pains at the age of 37. Erythrocyte sedimentation rate and C-reactive protein were abnormal, with negative antinuclear antibody and rheumatoid factor tests. The diagnosis of polymyalgia rheumatica (PMR) was made. She had HLA phenotypes including A2 and without DR4, consistent with common types of Japanese PMR. Her DNA typing included DQB1*0303 which is positively associated with Japanese IDDM. It seems likely that she suffered from these diseases at a young age on the basis of having the HLA-susceptibility to both PMR and IDDM.

Plasma free thyroxine (FT4) concentrations during hemodialysis in patients with chronic renal failure: effects of plasma non-esterified fatty acids on FT4 measurement.

Plasma free T4 (FT4) concentrations could be increased during hemodialysis in patients with chronic renal failure (CRF) because an increase in non-esterified fatty acids (NEFA) could interfere with the binding of T4 to thyroxine-binding globulin. To evaluate the effect of hemodialysis on the FT4 concentration in patients with CRF, we measured the FT4 in 39 patients with CRF by four assay methods including equilibrium dialysis, the 125I-T4 analog method and enzyme immunoassay. The addition of the fatty acid sodium oleate to normal pooled sera led to a marked increase in FT4 as measured by equilibrium dialysis (Model FT4). A moderate increase in the serum FT4 concentration also was observed with an IMX enzyme immunoassay kit, whereas the Coat-A-Count analog method demonstrated no interference by sodium oleate. The mean serum FT4 prior to hemodialysis measured by equilibrium dialysis did not differ significantly from that in the normal control, although those measured by analog methods (Coat-A-Count and Amerlex) and IMX were subnormal. The FT4 by IMX were albumin-dependent, and the values decreased as the samples were serially diluted, but Model FT4 was not affected by the albumin level or the serial dilution. FT4 by Model FT4 showed a marked increase beginning 10 min after the start of dialysis, and it correlated well with the plasma concentration of NEFA and the NEFA/albumin molar ratio. The other three assay methods, including one which is not affected by NEFA, did not show a change in FT4 at 10 min, but a significant increase of 11 to 17% was observed by the end of dialysis. The TSH concentration decreased significantly during hemodialysis. These data suggest that (1) the low serum FT4 in hemodialysis patients measured by some immunoassay methods may be an underestimation due to the low albumin level; (2) FT4 actually increases during hemodialysis due to the actual increase in NEFA, although the marked increase in FT4 during hemodialysis as measured by equilibrium dialysis is an overestimation due to the in vitro generation of NEFA; and (3) one should beware of aberrations in thyroid hormone parameters during hemodialysis and potential complications.

Thyroid cell proliferation-inhibiting activity in serum of patients with chronic renal failure on hemodialysis.

To investigate the possible humoral factor(s) influencing thyroid cell activity in chronic renal failure, we measured serum activity which stimulates or inhibits the [3H]thymidine incorporation by using a cultured functioning rat thyroid cell line (FRTL-5 cells) in 17 patients on hemodialysis and 19 healthy controls. Polyethylene glycol-treated serum was centrifuged and FRTL-5 cells were cultured with the supernatant. Thyroid stimulating activity was determined by [3H]thymidine incorporation after incubation for 72 h. There was no significant difference in [3H]thymidine incorporation between cultures incubated with patient and normal serum, suggesting the absence of the stimulating activity. But when patient serum was added to cultures together with 20 or 50 microU/ml of TSH, the TSH-stimulated increase in [3H]thymidine incorporation was significantly decreased, indicating the presence of thyroid inhibiting activity, which possibly inhibits the thyroid cell growth. This activity was not significantly altered by hemodialysis. No significant correlation was observed between this activity and serum levels of thyroid hormones or the iodine concentration. Patients on hemodialysis therefore have serum thyroid inhibiting activity which is nondialysable, differs from iodine, and could influence the thyroid cell growth.

A case of iatrogenic growth retardation induced by a corticosteroid-containing anti-allergic drug.

A nine-year old boy developed reduced growth velocity at the age of seven. The peak plasma growth hormone (GH) response to 3,4-dihydroxyphenylalanine, GH-releasing factor and insulin was 10.2, 8.1 and 7.6 micrograms/l, respectively, suggesting that the GH reserve was slightly reduced. Serum cortisol was undetectable and urinary excretion of 17-hydroxycorticosteroid was low (0.22-0.31 mg/day), but there were no physical or biochemical signs of adrenocortical insufficiency. He had taken an anti-allergic drug containing 0.25 mg of betamethasone and 2 mg of d-chlorpheniramine maleate per tablet for about 2 years to treat allergic rhinitis. Catch-up growth occurred when this drug was stopped. The present case suggests that daily administration of 0.25 mg of betamethasone can induce growth retardation and that ingestion of corticosteroid-containing preparations needs to be excluded in children who develop short stature without other symptoms.

Analysis of platelet abnormalities in uremia with and without Glanzmann's thrombasthenia.

Uremia causes a bleeding tendency associated with platelet dysfunction, and previous studies have shown abnormalities of platelet glycoprotein (GP) Ib or GPIIb/IIIa and a tendency for platelet activation in uremia. The present study compared the abnormalities of platelet function in uremia with (n = 1) or without (n = 18) associated Glanzmann's thrombasthenia. There was a significant difference between ristocetin-induced agglutination of platelets from the uremic patients without Glanzmann's thrombasthenia and platelets from healthy controls (n = 15). In addition, a reduction of GPIb expression by uremic platelets along with normal GPIIb/IIIa expression was confirmed using flow cytometry. Many coagulation markers were increased in the uremic patient with Glanzmann's thrombasthenia, suggesting that the coagulation was enhanced and the platelets were prone to activation. However, the thrombasthenic platelets actually showed little increase in the binding of a monoclonal anti-CD63 antibody directed against lysosomal integral membrane protein (which is expressed after platelet activation), while uremic platelets showed a marked increase. In addition, the expression of GPIb by thrombasthenic platelets was normal, while that of GPIIb/IIIa was markedly decreased. Our results suggest that thrombasthenic platelets are resistant to activation and to the degradation of GPIb under uremic condition and that this difference from 'ordinary' uremic platelets be related to the difference in GPIIb/IIIa.