Frequency of Hypoglycemia Assessed by Continuous Glucose Monitoring in Advanced CKD.

BACKGROUND: Hypoglycemia represents a risk for serious morbidity. We evaluated the prevalence and risk factors of hypoglycemia by continuous glucose monitoring (CGM) in patients with CKD with or without diabetes. METHODS: In this cross-sectional study, outpatients with CKD stages G3-G5 (including hemodialysis) and type 2 diabetes without CKD were enrolled and underwent intermittently scanned CGM measurements for 7 days. The burden of CGM-measured hypoglycemia was assessed using the 7-day sum of area over the curve with glucose levels <70 mg/dl and the sum of time spent <54 mg/dl. RESULTS: A total of 366 participants (148 participants with CKD and diabetes, 115 with CKD and without diabetes, and 103 without CKD and with diabetes) were included. Glucose levels of <54 mg/dl were observed in 41% of participants with CKD and diabetes, 48% of participants with CKD and without diabetes, and 14% of participants with diabetes and without CKD. However, only two participants reported hypoglycemic symptoms during CGM measurements, which were confirmed and documented by capillary blood glucose measurements. Between-group differences of 7-day area over the curve (<70 mg/dl) were as follows: hemodialysis group versus CKD stage G4 and G5 groups, -0.25 min·mg/dl per hour (95% confidence interval [CI], -6.40 to -0.59) P <0.001; CKD stage G4 and G5 groups versus CKD stage G3 group, -0.08 min·mg/dl per hour (95% CI, -0.0 to -0.50) P =0.15; and CKD stage G3 group versus diabetes without CKD group, -0.14 min·mg/dl per hour (95% CI, -0.0 to -0.20) P =0.01. In addition, the subgroup analysis of the diabetic or nondiabetic and at daytime or nighttime showed that the 7-day area over the curve (<70 mg/dl) and time spent (<54 mg/dl) was larger with worse kidney function. CONCLUSIONS: The lowering level of kidney function was strongly associated with the burden of hypoglycemia in patients with CKD.

The effects of ipragliflozin on the liver-to-spleen attenuation ratio as assessed by computed tomography and on alanine transaminase levels in Japanese patients with type 2 diabetes mellitus.

We assessed the effects of a 12-week ipragliflozin treatment on the liver-to-spleen attenuation ratio (L/S ratio) using computed tomography and on alanine transaminase (ALT) levels in Japanese patients with type 2 diabetes mellitus (T2DM). Sixty-two patients with T2DM [age, 56 ± 8 years; hemoglobin A1c (HbA1c) levels, 8.1 ± 0.9%; body mass index (BMI), 27.5 ± 3.3 kg/m2] were randomly assigned in a 2:1 ratio to receive ipragliflozin (50 mg/day; ipragliflozin group; n = 40) or continued treatment (control group; n = 22) for 12 weeks. The primary endpoints were changes in ALT levels; the secondary endpoints included changes in the L/S ratio and in the visceral fat area (VFA) and subcutaneous fat area (SFA) before and after 12 weeks of the treatment as assessed by computed tomography. ALT levels (-12.45 vs. +5.82 IU/l, P < 0.001), L/S ratio (+0.07 vs. -0.08, P < 0.001), SFA (-5.8 vs. +13.3 cm2, P < 0.05), and VFA (+1.4 vs. +20.4 cm2, P < 0.05) significantly changed from baseline in the ipragliflozin group compared with the values in the control group. Multiple regression analysis among all subjects revealed that the independent factor contributing to the %ΔALT and %ΔL/C ratio was treatment group alone (ipragliflozin group = 1; control group = 0; ß coefficient = -32.08, P < 0.001 and ß coefficient = 19.98, P < 0.05, respectively). Thus, ipragliflozin may lower ALT levels associated with increased L/S ratios, indicating its potential therapeutic efficacy in T2DM-associated hepatic steatosis.

Serum CETP status is independently associated with reduction rates in LDL-C in pitavastatin-treated diabetic patients and possible involvement of LXR in its association.

BACKGROUND: Statins decrease cholesteryl ester transfer protein (CETP) levels, which have been positively associated with hepatic lipid content as well as serum low density lipoproteins-cholesterol (LDL-C) levels. However, the relationship between the CETP status and statin-induced reductions in LDL-C levels has not yet been elucidated in detail. We herein examined the influence of the CETP status on the lipid-reducing effects of pitavastatin in hypercholesterolemic patients with type 2 diabetes mellitus as well as the molecular mechanism underlying pitavastatin-induced modifications in CETP levels. METHODS: Fifty-three patients were treated with 2 mg of pitavastatin for 3 months. Serum levels of LDL-C, small dense (sd) LDL-C, and CETP were measured before and after the pitavastatin treatment. The effects of pitavastatin, T0901317, a specific agonist for liver X receptor (LXR) that reflects hepatic cholesterol contents, and LXR silencing on CETP mRNA expression in HepG2 cells were also examined by a real-time PCR assay. RESULTS: The pitavastatin treatment decreased LDL-C, sdLDL-C, and CETP levels by 39, 42, and 23%, respectively. Despite the absence of a significant association between CETP and LDL-C levels at baseline, baseline CETP levels and its percentage change were an independent positive determinant for the changes observed in LDL-C and sdLDL-C levels. The LXR activation with T0901317 (0.5 µM), an in vitro condition analogous to hepatic cholesterol accumulation, increased CETP mRNA levels in HepG2 cells by approximately 220%, while LXR silencing markedly diminished the increased expression of CETP. Pitavastatin (5 µM) decreased basal CETP mRNA levels by 21%, and this was completely reversed by T0901317. CONCLUSION: Baseline CETP levels may predict the lipid-reducing effects of pitavastatin. Pitavastatin-induced CETP reductions may be partially attributed to decreased LXR activity, predictable by the ensuing decline in hepatic cholesterol synthesis. TRIAL REGISTRATION: UMIN Clinical Trials Registry ID UMIN000019020.

Switching from atorvastatin to rosuvastatin lowers small, dense low-density lipoprotein cholesterol levels in Japanese hypercholesterolemic patients with type 2 diabetes mellitus.

AIMS: This open-label, randomized, parallel-group comparative study compared the efficacy of rosuvastatin (5mg/day) and atorvastatin (10mg/day) for reduction of small dense low-density lipoprotein cholesterol (sd LDL-C) levels in Japanese patients with type 2 diabetes mellitus (T2DM). METHODS: Patients with T2DM and hypercholesterolemia with detectable sd LDL-C after receiving 10mg/day atorvastatin for ≥ 24 weeks were randomly assigned to receive rosuvastatin (5mg/day; switched treatment) or atorvastatin (10mg/day; continued treatment) for 12 weeks. The primary endpoints were changes in sd LDL-C levels and sd LDL-C/total LDL-C ratio evaluated using the LipoPhor AS(®) system. RESULTS: There were no significant percent changes from baseline for LDL-C levels between the switched (n=55) and the continued treatment group (n=56). However, the former group exhibited a statistically significant reduction from baseline of sd LDL-C levels, sd LDL-C/total LDL-C ratio compared with the latter group (-3.8 mg/dL vs. -1.4 mg/dL, p=0.014; -2.3% vs. -0.6%, p=0.004, respectively). Multiple regression analysis among all subjects revealed that independent factors contributing to the reduction in sd LDL-C levels were a change in LDL-C (p=0.003) and triglyceride (TG) levels (p=0.006), treatment group (the switched group=1, the continued group=0; standard coefficient=-1.2, p=0.034) and baseline glycated hemoglobin A1c (HbA1c) (p=0.045), respectively. CONCLUSION: Switching from 10mg atorvastatin to 5mg rosuvastatin may be a useful therapeutic option to reduce sd LDL-C levels in Japanese hypercholesterolemic patients with T2DM.

Ipragliflozin lowers small, dense low-density lipoprotein cholesterol levels in Japanese patients with type 2 diabetes mellitus.

AIMS: This preliminary randomized, parallel-group comparative study evaluated the efficacy of ipragliflozin for reduction of small dense low-density lipoprotein cholesterol (sd LDL-C) levels in Japanese patients with type 2 diabetes mellitus (T2DM). METHODS: Sixty-two patients with T2DM (age, 56 ± 8 years; hemoglobin A1c levels, 8.1 ± 0.9%; BMI, 27.5 ± 3.3 kg/m2) were randomly assigned in a 2:1 ratio to receive ipragliflozin (50 mg/day) (treatment group; n = 40) or continued treatment (control group; n = 22) for 12 weeks. The primary endpoints were changes in sd LDL-C levels detected using the LipoPhor AS® system; the secondary endpoints included changes in the sd LDL-C/large buoyant LDL-C (lb LDL-C) ratio, a surrogate marker for LDL particle size, and percent changes in routine lipid parameters. RESULTS: The treatment group exhibited a statistically significant reduction from baseline for LDL-C levels (-0.37 mg/dL vs. 14.4 mg/dL, p = 0.038), sd LDL-C levels (-1.28 mg/dL vs. 2.81 mg/dL, p = 0.012), and sd LDL-C/lb LDL-C ratio (-3.20% vs. 4.58%, p = 0.040) compared with the control group. Multiple regression analysis among all subjects revealed change in TG levels (p = 0.011) and LDL-C levels (p = 0.024) as well as change in body weight (p = 0.006) as independent factors contributing to the reduction in sd LDL-C. CONCLUSIONS: Ipragliflozin may have a potential for lowering sd LDL-C levels associated with increasing LDL particle size in Japanese patients with T2DM.

Non-high-density cholesterol level as a predictor of maximum carotid intima-media thickness in Japanese subjects with type 2 diabetes: a comparison with low-density lipoprotein level.

AIM: To determine whether non-high-density lipoprotein cholesterol (non-HDL-C) level, in comparison with low-density lipoprotein cholesterol (LDL-C) level, is useful for predicting the values of various surrogate atherosclerosis markers in Japanese subjects with type 2 diabetes (T2DM). METHODS: Data were retrieved from medical records of 265 subjects with T2DM who underwent laboratory tests to evaluate for atherosclerosis by using the following parameters: brachial-ankle pulse wave velocity, mean and maximum carotid intima-media thickness (mean CIMT and max-CIMT), and ankle-brachial index, with simultaneous fasting blood sampling for routine lipid parameters. RESULTS: In a multiple stepwise regression analysis, non-HDL-C level, but not LDL-C level, positively correlated with max-CIMT (ß coefficient = 0.14, F = 6.84). Stepwise logistic regression analysis revealed that a 0.26 mmol/L (10 mg/dL) increase in non-HDL-C level, but not LDL-C level, was significantly associated with high risk of max-CIMT (≥1.1 mm; odds ratio, 1.096; 95 % confidence interval, 1.003-1.202; p = 0.046). However, in a receiver operating characteristic curve (ROC) analysis, the addition of non-HDL-C level to the three significant independent variables obtained from the stepwise analyses did not significantly increased the area under the ROC curve (from 0.7789 to 0.7864, p = 0.4343). CONCLUSIONS: Non-HDL-C levels may be non-inferior to LDL-C level for the prediction of high-risk max-CIMT in Japanese subjects with T2DM.

Chronic hyperglycemia may attenuate the serum-uric-acid-lowering effect of low-dose febuxostat in Japanese patients with type 2 diabetes mellitus.

AIMS: This study investigated the independent predictors of the serum uric acid (sUA)-lowering effect of low-dose febuxostat, a novel xanthine oxidase inhibitor, in Japanese patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: Data of 130 T2DM patients who had been taking febuxostat 10 mg once daily for elevated sUA (≥7 mg/dl) for at least 12 weeks were retrieved from medical records. Spearman's rank correlation coefficients were calculated to determine the correlations between sets of two independent continuous variables. Multiple stepwise linear regression analysis was used to determine independent predictors of the percent change of sUA levels after 12 weeks of febuxostat treatment (%ΔsUA). RESULTS: Among all patients, %ΔsUA was significantly correlated with age (ρ = 0.192, P = 0.030) and mean glycated hemoglobin (HbA1c) level (ρ = -0.186, P = 0.036). Multiple stepwise linear regression analysis of all patients revealed that major independent factors contributing to %ΔsUA were mean HbA1c (ß = -3.14, P = 0.022) and mean glycated albumin (ß = -0.743, P = 0.013) levels. CONCLUSIONS: High HbA1c and glycated albumin levels significantly attenuated the sUA-lowering effect of low-dose febuxostat in Japanese patients with T2DM. Further detailed analysis using a larger population is warranted to confirm these findings.

Is glycated albumin useful for differential diagnosis between fulminant type 1 diabetes mellitus and acute-onset autoimmune type 1 diabetes mellitus?

BACKGROUND: Markedly elevated plasma glucose and relatively low HbA1c compared to plasma glucose is one diagnostic criterion for fulminant type 1 diabetes mellitus (FT1DM). Glycated albumin (GA) is a glycemic control marker that reflects glycemic control in shorter period than HbA1c. This study investigated whether GA is useful for differential diagnosis between FT1DM and acute-onset autoimmune type 1 diabetes mellitus (T1ADM) or not. METHODS: This study included 38 FT1DM patients and 31 T1ADM patients in whom both HbA1c and GA were measured at the time of diagnosis. RESULTS: In FT1DM patients, as compared to T1ADM patients, both HbA1c and GA were significantly lower (HbA1c; 6.6±0.9% vs. 11.7±2.6%, P<0.0001, GA; 22.9±4.8% vs. 44.3±8.3%, P<0.0001). For differential diagnosis between FT1DM and T1ADM, ROC analysis showed that the optimum cut-off value for GA was 33.5% with sensitivity and specificity of 97.4% and 96.8%, respectively, while the optimum cut-off value for HbA1c was 8.7% with sensitivity and specificity of 100% and 83.9%, respectively. CONCLUSIONS: GA also may be useful for the differential diagnosis between FT1DM and T1ADM when the cut-off value can be set at 33.5%.

The glycated albumin to glycated haemoglobin ratio increases along with the fibrosis stage in non-alcoholic steatohepatitis.

BACKGROUND: We previously reported that the indicator of glycaemic control, glycated albumin (GA) levels, are low in relation to glycaemia in patients with high alanine aminotransferase (ALT) levels in non-alcoholic fatty liver disease because of chronic inflammation, and that the GA/glycated haemoglobin ratio (G/H ratio) is inversely correlated with hepatic function in patients with chronic liver disease. The severity of liver fibrosis is known to be a good indicator for surveillance, and for determining the prognosis and optimal treatment of non-alcoholic steatohepatitis (NASH). In this study, we aimed to investigate the clinical usefulness of measuring the G/H ratio for predicting the severity of liver fibrosis in patients with NASH. METHODS: The study subjects were 36 patients with histologically diagnosed NASH (19 men, 17 women; mean age 54.8±12.2 years, body mass index 28.3±5.0 kg/m2). The relationships of the G/H ratio to hepatic function tests and fibrosis stage in the liver were investigated. RESULTS: The G/H ratio in patients with NASH was inversely correlated with ALT (P<0.001) and platelet count (P<0.0001). Furthermore, the G/H ratio was positively correlated with the fibrosis stage in liver (P=0.003). CONCLUSIONS: These results suggest that the G/H ratio increases along with the fibrosis stage in patients with NASH.

Obesity may attenuate the HbA1c-lowering effect of sitagliptin in Japanese type 2 diabetic patients.

UNLABELLED: Aims/Introduction: The aim of the present study was to assess the independent predictors of the HbA1c-lowering effect of sitagliptin in Japanese type 2 diabetic patients. MATERIALS AND METHODS: Data were retrieved from the medical records of 151 type 2 diabetic patients who had been taking sitagliptin 25 or 50 mg once daily for inadequate glycemic control for at least 12 weeks, with or without other oral hypoglycemic agents. Spearman's rank correlation coefficients were calculated to investigate correlations between two independent continuous variables. Multiple stepwise regression analysis was used to identify independent predictors of reductions in HbA1c levels after 12 weeks of sitagliptin treatment (ΔHbA1c). RESULTS: In all patients combined, Spearman's rank correlation coefficients showed that ΔHbA1c was significantly correlated with baseline HbA1c alone (r = 0.371, P < 0.0001). However, multiple linear regression analysis among all patients using baseline variables revealed that the independent factors contributing to ΔHbA1c, in order of importance, were method of prescribing (P < 0.0001), baseline HbA1c (P < 0.0001), body mass index (BMI; P = 0.004), and duration of diabetes (P = 0.024). CONCLUSIONS: Our analysis may provide novel evidence that increased BMI contributes, in part, to attenuation of the HbA1c-lowering effect of sitagliptin in Japanese type 2 diabetic patients. Analysis of a larger population over a longer period of time is warranted to confirm these findings. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00156.x, 2011).

Glycated albumin levels are higher relative to HbA1c levels in people with autoimmune acute-onset type 1 diabetes mellitus than in people with type 2 diabetes mellitus at the time of diagnosis.

Glycated albumin (GA) is a new glycemic control indicator. GA/HbA1c ratio in autoimmune acute-onset type 1 diabetes mellitus patients was significantly higher than in type 2 diabetes mellitus patients at the time of diagnosis. This difference might reflect speed of increase in plasma glucose after the onset of diabetes.

1,5-Anhydroglucitol levels are low irrespective of plasma glucose levels in patients with chronic liver disease.

BACKGROUND: Serum 1,5-anhydroglucitol (1,5-AG) is a known marker reflecting recent glycaemic control. In this study, we examined serum 1,5-AG levels in chronic liver disease (CLD) patients with and without diabetes mellitus. METHODS: Eighty patients with CLD were compared with 667 subjects without CLD. Glycaemic control of the CLD patients was evaluated by estimated glycated haemoglobin (HbA(1C)) calculated using the equation by Rohlfing et al. from mean plasma glucose because CLD patients have apparently low HbA(1C). RESULTS: When the study participants were divided into subgroups stratified by HbA(1C) levels, the CLD patients whose estimated HbA(1C) levels were less than 7.0% showed significantly lower 1,5-AG than their counterparts of the control subjects. Stepwise multivariable analysis revealed that estimated HbA(1C) was the significant explanatory variable for 1,5-AG in the CLD patients. However, in the CLD patients with estimated HbA(1C) less than 5.8%, only hepaplastin test was the significant explanatory variable for 1,5-AG. CONCLUSIONS: Serum 1,5-AG levels are low irrespective of plasma glucose levels in the CLD patients with and without diabetes. The CLD patients who had low serum 1,5-AG levels were associated with deteriorated liver function.

Association of serum glycated albumin to haemoglobin A1C ratio with hepatic function tests in patients with chronic liver disease.

BACKGROUND: In patients with chronic liver disease (CLD), glycated haemoglobin (HbA(1C)) levels have been shown to be apparently lower than real values, whereas serum glycated albumin (GA) levels are apparently higher. The present study was aimed to examine whether both glycaemic indices are influenced by hepatic function. METHODS: Subjects consisted of 82 patients with CLD. Various indicators for hepatic function as well as HbA(1C) and GA were also measured. Estimated HbA(1C) values were calculated from the mean plasma glucose levels. Two hundred and two type 2 diabetic patients without CLD were studied as controls. RESULTS: Although GA was strongly correlated with HbA(1C) in patients with CLD as well as diabetic patients, GA levels in patients with CLD were relatively higher than those in diabetic patients. In patients with estimated HbA(1C) < or = 5.8%, GA levels significantly increased but HbA(1C) levels decreased as a function of decreasing hepaplastin test (HPT). The ratio of GA/HbA(1C) (G/H ratio) increased as a function of decreasing HPT. In patients with estimated HbA(1C) > 5.8%, in contrast, GA levels were independent of HPT levels. In the patients with CLD, GA and HbA(1C) were associated with mean plasma glucose levels and some indicators for hepatic function. The multivariate analysis revealed a significant association of G/H ratio with HPT, cholinesterase and direct bilirubin. The G/H ratio was not associated with the mean plasma glucose but with HPT and cholinesterase levels. CONCLUSIONS: The G/H ratio correlates with hepatic function but not with plasma glucose levels. Therefore, CLD should be suspected for diabetic patients with an elevated G/H ratio.

Characteristics of undiagnosed diabetes mellitus in a population undergoing health screening in Japan: target populations for efficient screening.

AIMS: To estimate the prevalence of undiagnosed diabetes mellitus and its relationship with various risk factors in a population undergoing health screening in Japan. METHODS: Oral glucose tolerance tests were carried out in a total sample of 14,674 Japanese subjects undergoing health screening, aged 20-83 years and without known diabetes. The prevalence of glucose tolerance categories (1999 WHO criteria) was adjusted for sample probabilities. The optimal FPG cut-off point for screening diabetes was estimated using ROC curve analysis for the continuous value of FPG corresponding to a 2-h PG of 200 mg/dl. The number needed to screen (NNTS) to identify one person with undiagnosed diabetes with various risk factors was estimated using the following equation: the number of undiagnosed diabetic plus nondiabetic subjects/the number of undiagnosed diabetic subjects. RESULTS: The prevalence of undiagnosed diabetes among men and women was 6.4% (NNTS 15.7) and 3.2% (NNTS 31.7), respectively. The optimal FPG cut-off point for screening diabetes among men and women was 105 and 106 mg/dl, respectively. NNTS was lower in individuals with more risk factors, e.g. aging (> or =50), BMI (> or =25), hypertension (SBP> or =140 mmHg and/or DBP> or =90 mmHg) and dyslipidemia (TC> or =220 and/or HDL-C<40 and/or TG> or =150 mg/dl), resulting in the lowest NNTS in individuals having all four risk factors among men (6.1) and women (6.7), respectively. CONCLUSIONS: In Japan, screening for diabetes may be more efficient among individuals having an FPG of more than 105-106 mg/dl and with more risk factors, especially in men.

CLD (chronic liver diseases)-HbA1C as a suitable indicator for estimation of mean plasma glucose in patients with chronic liver diseases.

In patients with chronic liver diseases (CLD), turnover of erythrocytes is increased whereas that of serum albumin is decreased. Thus, glycated hemoglobin (HbA(1C)) and glycated albumin (GA) cannot be used as adequate indicators for chronic plasma glucose control in diabetic patients with CLD. In this investigation, we have proposed CLD-HbA(1C), a novel long-term glycemic control marker by using measured HbA(1C) and GA. We studied 82 patients with CLD in whom glycemic control was regarded as to be stable. Daily plasma glucose profiles were monitored and estimated levels of HbA(1C) were calculated on the conversion formula established by Rohlfing et al. [C.L. Rohlfing, J.D. England, H.M. Wiedmeyer, A. Tennill, R.R. Little, D.E. Goldstein, Defining the relationship between plasma glucose and HbA1c, Diabetes Care 25 (2002) 275-278]. Cholinesterase (ChE) as an indicator for hepatic function was determined at the same time when HbA(1C) and GA levels were measured. CLD-HbA(1C) was defined as the average of measured HbA(1C) and GA/3, based upon the results that among healthy individuals, GA levels were roughly estimated at approximately threefold higher than HbA(1C) levels. While measured HbA(1C) levels in patients with CLD were generally lower than estimated HbA(1C) levels, GA/3 values were generally higher than estimated HbA(1C) levels. Such discrepancies lineally increased in accordance with a decrease in ChE levels. On the other hand, CLD-HbA(1C) levels were highly correlated with estimated HbA(1C) levels (R=0.883), while no significant correlation between CLD-HbA(1C) and ChE was noted. In conclusion, CLD-HbA(1C) has been found a superior chronic glycemic control marker than HbA(1C) or GA in diabetic patients with chronic liver diseases.

Myxedema ascites with an extremely elevated CA125 Level: a case report.

Carbohydrate antigen 125 (CA125) is a tumor-marker frequently associated with ovarian malignancies; however, benign gynecologic conditions (e.g. ovarian cysts) commonly cause a smaller increase in CA125 levels. This report describes an elderly Japanese woman with high CA125 levels and massive ascites caused by hypothyroidism. A 67-year-old woman presented herself with a weight gain of about 12 kg and abdominal distension. Her serum CA125 level was markedly elevated (822 U/ml) and abdominal CT revealed a right ovarian cyst and massive ascites. Hormonal laboratory data showed severe primary hypothyroidism with a serum TSH of 594 IU/L and a free thyroxin level of 0.05 ng/dl. Ascitic fluid was found to be exudate with a high protein content of 42 g/L. Cytological analysis and FDG-PET showed no evidence of malignancy. The ascites completely disappeared and serum CA125 normalized after adequate hormonal replacement therapy. These data suggest that hypothyroidism should be considered in patients with ascites and elevated serum CA125.

Function of hormone-sensitive lipase in diacylglycerol-protein kinase C pathway.

To explore the functional effects of hormone-sensitive lipase (HSL) in diacylglycerol (DAG) metabolism, Chinese hamster ovary cells were stably transfected with rat HSL cDNA (wt-HSL), inactive mutant S423A-HSL cDNA (S423A) and pcDNA3 vector alone (Ct). [(14)C]Glucose-incorporation into triglyceride (TG) was 75% lower in the presence or absence of insulin in cells expressing wt-HSL compared to Ct or S423A. [(14)C]Glucose-incorporation into DAG was 33% lower without insulin and 51% lower with insulin in cells expressing wt-HSL compared to Ct or S423A. Insulin stimulated glucose-incorporation into DAG 2.2-fold in S423A and Ct cells, whereas only a 50% increase was observed in cells expressing wt-HSL. Phospholipase C-mediated release of DAG from membrane phospholipids was reduced 70% in cells expressing wt-HSL compared to Ct or S423A. Western blot analysis showed that membrane-bound protein kinase C (PKC)-alpha and -epsilon were decreased 40-50% in cells expressing wt-HSL grown in high glucose with insulin. These data show that HSL potentially hydrolyzes cellular DAG generated either by de novo synthesis from glucose or release from membrane phospholipids by phospholipase C, resulting in a reduction in the translocation of DAG-sensitive PKCs.

Effect of cilostazol on impaired vasodilatory response of the brachial artery to ischemia in smokers.

The vascular endothelial function of smokers is known to be impaired. This study investigated whether cilostazol could improve the vasodilatory response of the brachial artery to ischemia, an indicator of endothelial function, in ten male smokers. Endothelium-dependent vasodilatation and endothelium-independent vasodilatation of the brachial artery were measured in 11 male non-smokers and 20 male smokers with matching age and weight. The results showed that the vasodilatory response to reactive hyperemia was significantly smaller in the smokers (4.8 +/- 1.6%) when compared to that in the non-smokers (7.6 +/- 2.5%) (p = 0.0013). However, no significant difference in the vasodilatory response to isosorbide dinitrate was observed between the two groups. In addition, there were no significant differences in serum lipid, Lp (a), or blood homocysteine between the smokers and non-smokers. When 150 mg/day of cilostazol was administered for two weeks, the vasodilatory response to reactive hyperemia significantly improved (4.2 +/- 1.2% to 7.8 +/- 3.5%, p = 0.0032). The increased vasodilatory response to reactive hyperemia by cilostazol was reduced after cessation of the drug (4.5 +/- 1.5%). These findings suggest that cilostazol improves vascular endothelial dysfunction in smokers.

Pitavastatin-induced thrombomodulin expression by endothelial cells acts via inhibition of small G proteins of the Rho family.

OBJECTIVE: 3-hydroxyl-3-methyl coenzyme A reductase inhibitors (statins) can function to protect the vasculature in a manner that is independent of their lipid-lowering activity. The main feature of the antithrombotic properties of endothelial cells is an increase in the expression of thrombomodulin (TM) without induction of tissue factor (TF) expression. We investigated the effect of statins on the expression of TM and TF by endothelial cells. METHODS AND RESULTS: The incubation of endothelial cells with pitavastatin led to a concentration- and time-dependent increase in cellular TM antigen and mRNA levels. In contrast, the expression of TF mRNA was not induced under the same conditions. A nuclear run-on study revealed that pitavastatin accelerates TM transcription rate. The stimulation of TM expression by pitavastatin was prevented by either mevalonate or geranylgeranylpyrophosphate. Specific inhibition of geranylgeranyltransferase-I and Rac/Cdc42 by GGTI-286 and Clostridium sordellii lethal toxin, respectively, enhanced TM expression, whereas inactivation of Rho by Clostridium botulinum C3 exoenzyme was ineffective. CONCLUSIONS: Statins regulate TM expression via inhibition of small G proteins of the Rho family; Rac/Cdc42. A statin-mediated increase in TM expression by endothelial cells may contribute to the beneficial effects of statins on endothelial function.