Fibroblast growth factor 23 inhibits osteoblastic gene expression and induces osteoprotegerin in vascular smooth muscle cells.

BACKGROUND AND AIMS: Elevated fibroblast growth factor 23 (FGF23) levels are associated with cardiovascular mortality in patients with chronic kidney disease. However, both clinical and basic research have demonstrated conflicting evidence regarding the pathophysiological role of FGF23 in vascular calcification. The aim of this study was to determine the role of FGF23 in the osteoblastic gene expression in vascular smooth muscle cells (SMCs). METHODS AND RESULTS: We transduce human aortic SMCs (HASMCs) expressing klotho and FGF receptors with the adenovirus expressing human FGF23 (Ad-FGF23). We observed significant decreases in the expression of osteoblast-marker genes including BMP2, BMP4, MSX2, RUNX2 and ALP, as well as reduced calcification. Notably, Ad-FGF23 increased mRNA and protein levels of osteoprotegerin (OPG), and human OPG promoter was activated by FGF23. Moreover, in HASMCs overexpressing klotho, FGF23 upregulated OPG expression, whereas depletion of klotho by siRNA attenuated FGF23-induced OPG expression. Furthermore, in 73 consecutive patients with type 2 diabetes mellitus undergoing cardiac computed tomography to determine coronary calcium scores (CCSs), serum FGF23 levels were positively correlated with OPG independent of phosphate and estimated glomerular filtration rate (eGFR, r = 0.65, p < 0.01). Serum FGF23 levels were significantly elevated in patients with high CCSs (≧100) compared to those with low CCSs (<100). CONCLUSIONS: Our in vitro results indicate that FGF23 suppresses osteoblastic gene expression and induces OPG expression in HASMCs. Together with our cross-sectional clinical assessment, the present study lends support to our hypothesis that FGF23 counteracts osteogenic conversion of vascular SMCs as a part of a compensatory mechanism to mitigate vascular calcification.

Constitutively active heat shock factor 1 enhances glucose-driven insulin secretion.

Weak pancreatic ß-cell function is a cause of type 2 diabetes mellitus. Glucokinase regulates insulin secretion via phosphorylation of glucose. The present study focused on a system for the self-protection of pancreatic cell by expressing heat shock factor (HSF) and heat shock protein (HSP) to improve insulin secretion without inducing hypoglycemia. We previously generated a constitutively active form of human HSF1 (CA-hHSF1). An adenovirus expressing CA-hHSF1 using the cytomegalovirus promoter was generated to infect mouse insulinoma cells (MIN6 cells). An adenovirus expressing CA-hHSF1 using a human insulin promoter (Ins-CA-hHSF1) was also generated to infect rats. We investigated whether CA-hHSF1 induces insulin secretion in MIN6 cells and whether Ins-CA-hHSF1 can improve blood glucose and serum insulin levels in healthy Wister rats and type 2 diabetes mellitus model rats. CA-hHSF1 expression increased insulin secretion 1.27-fold compared with the overexpression of wild-type hHSF1 in MIN6 cells via induction of HSP90 expression and subsequent activation of glucokinase. This mechanism is associated with activation of both glucokinase and neuronal nitric oxide synthase. Ins-CA-hHSF1 improved blood glucose levels in neonatal streptozotocin-induced diabetic rats. Furthermore, Ins-CA-hHSF1 reduced oral glucose tolerance testing results in healthy Wister rats because of an insulin spike at 15 minutes; however, it did not induce hypoglycemia. CA-hHSF1 induced insulin secretion both in vitro and in vivo. These findings suggest that gene therapy with Ins-CA-hHSF1 will be able to be used to treat patients with type 2 diabetes mellitus and impaired glucose tolerance without causing hypoglycemia at fasting.

Clinical significance of neutrophil apoptosis in peripheral blood of patients with type 2 diabetes mellitus.

UNLABELLED: Although neutrophils are essential components of the natural immune system, they have also been implicated in the pathogenesis of tissue injuries. We assessed the clinical significance of neutrophil apoptosis in the peripheral blood of patients with type 2 diabetes mellitus (T2DM). PATIENTS AND METHODS: The study included 52 patients with T2DM (30 men, 22 women). Control subjects were 16 healthy volunteers without diabetes (7 men, 9 women). Neutrophil apoptosis levels were measured active caspase-3 positive rate by flow cytometry. RESULTS: The mean rate of neutrophil apoptosis in patients with T2DM was 15.0% (95% confidence interval [CI]: 9.5% approximately 20.5%), while that in the control group was 5.8% (95% CI: 1.6% approximately 10.0%). There were significant negative correlations between neutrophil apoptosis rate and hemoglobin (Hb) A1c levels (r = -0.352, P < .01). The mean rate of neutrophil apoptosis in the patient group with the 3 major complications (diabetic retinopathy, nephropathy, and neuropathy) was 11.1% (95% CI: 5.5%-16.7%, n = 36) and that of another group without complications was 23.8% (95% CI: 11.4%-36.2%, n = 16). There was a significant difference between these 2 groups (P < .05). CONCLUSIONS: The neutrophil apoptosis rate in patients with T2DM was significantly correlated with HbA1C levels. The mean rate of neutrophil apoptosis in the patient group with 3 major diabetic complications remained lower than that in another patient group without complications. The inhibition of neutrophil apoptosis by chronic hyperglycemia is thought to promote tissue injury and to enhance the risk of microangiopathy.

Doctor-patient communication: a comparison between telemedicine consultation and face-to-face consultation.

OBJECTIVE: The objective of this study was to compare doctor-patient communications in clinical consultations via telemedicine technology to doctor-patient communications in face-to-face clinical consultations. METHOD: Five doctors who had been practicing internal medicine for 8 to 18 years, and twenty patients were enrolled in this study; neither doctors nor patients had previous experience of telemedicine. The patients received both a telemedicine consultation and a face-to-face consultation. Three measures--video observation, medical record volume, and participants' satisfaction--were used for the assessment. RESULTS: It was found that the time spent on the telemedicine consultation was substantially longer than the time spent on the face-to-face consultation. No statistically significant differences were found in the number of either closed or open-ended questions asked by doctors between both types of consultation. Empathy-utterances, praise-utterances, and facilitation-utterances were, however, seen less in the telemedicine consultations than in the face-to-face consultations. The volume of the medical records was statistically smaller in the telemedicine consultations than in the face-to-face consultations. Patients were satisfied with the telemedicine consultation, but doctors were dissatisfied with it and felt hampered by the communication barriers. CONCLUSIONS: This study suggests that new training programs are needed for doctors to develop improved communication skills and the ability to express empathy in telemedicine consultations.

HSF1 and constitutively active HSF1 improve vascular endothelial function (heat shock proteins improve vascular endothelial function).

We have been examining the role of heat shock factor 1 (HSF1) in the pleiotropic effects of statins. In parallel studies, we found that statin induces the nuclear translocation of HSF1 and that a decoy oligonucleotide encoding the heat shock element inhibits the statin-induced expression of heat shock protein 70, endothelial nitric oxide synthase (eNOS) and thrombomodulin. Also, in vascular endothelial cells, increases in the expression of human HSF1 corresponded with elevated steady-state levels of eNOS and thrombomodulin and reduced levels of endothelin-1 and plasminogen activator inhibitor-1. We also found that heat shock proteins induced eNOS and thrombomodulin expression and reduced PAI-1 and ET-1 expression. In particular, a combination of HSP70 and HSP90 strongly induced eNOS expression and reduced PAI-1 expression. In the current studies, we generated a constitutively active form of HSF1 and found that it is more effective than the wild-type HSF at inducing thrombomodulin and eNOS expression and decreasing endothelin-1 and plasminogen activator inhibitor-1 expression. These results show that the wild-type and constitutively active forms of HSF1 induce anticoagulation and relaxation factors in vascular endothelial cells and could therefore be used to treat cardiovascular disease.

Simvastatin induces heat shock factor 1 in vascular endothelial cells.

Statins not only reduce serum cholesterol but they also improve vascular endothelial function independent of their lipid-lowering effects. However, except for the mechanism of nitric oxide induction via calveolin, the physiologic basis for the pleiotropic effect of statins remains unknown. In the present study, we investigated the relationship between the effects of statins on vascular endothelial cell function and heat shock proteins. We found that, in vascular endothelial cells, simvastatin increased the steady-state levels of heat shock proteins 90 and 70, and heme oxygenase-1 and caused the nuclear translocation of heat shock factor 1. A decoy oligonucleotide encoding the heat shock element inhibited statin-induced expression of heat shock protein 70, endothelial nitric oxide synthase, and thrombomodulin. This decoy oligonucleotide also inhibited the ability of statin to reduce endothelin-1 and plasminogen activator inhibitor-1 expression. These results indicate that statins improve vascular endothelial function via heat shock factor 1, which may contribute to their ability to improve cardiovascular disease.

Type 2 diabetes mellitus complicated with smoldering myeloma and non-alcoholic steatohepatitis.

We report a 59-year-old woman with type 2 diabetes mellitus (DM) complicated with smoldering myeloma and non-alcoholic steatohepatitis. A diagnosis of smoldering myeloma was made on the basis of elevation of IgA, M-protein (type:IgA-lambda) and histological findings of bone marrow without bone lesion. As to liver dysfunction, anti-HBV, anti-HCV and a series of auto-immune antibody were negative. She had no alcohol drinking habit and histological findings showed pericellular fibrosis without fatty degeneration, suggesting liver cirrhosis due to non-alcoholic steatohepatitis (NASH). To date, there are no reports of cases with DM, NASH and myeloma. Particular attention may be necessary for these complications.

CD40 ligation releases immature dendritic cells from the control of regulatory CD4+CD25+ T cells.

We report that disruption of CD154 in nonobese diabetic (NOD) mice abrogates the helper function of CD4+CD25- T cells without impairing the regulatory activity of CD4+CD25+ T cells. Whereas CD4+ T cells from NOD mice enhanced a diabetogenic CD8+ T cell response in monoclonal TCR-transgenic NOD mice, CD4+ T cells from NOD.CD154(-/-) mice actively suppressed it. Suppression was mediated by regulatory CD4+CD25+ T cells capable of inhibiting CD8+ T cell responses induced by peptide-pulsed dendritic cells (DCs), but not peptide/MHC monomers. It involved inhibition of DC maturation, did not occur in the presence of CD154+ T-helper cells, and could be inhibited by activation of DCs with LPS, CpG DNA, or an agonistic anti-CD40 mAb. Thus, in at least some genetic backgrounds, CD154-CD40 interactions and innate stimuli release immature DCs from suppression by CD4+CD25+ T cells.

Hormone replacement therapy decreases insulin resistance and lipid metabolism in Japanese postmenopausal women with impaired and normal glucose tolerance.

OBJECTS: To investigate the effect of combined estrogen and progesterone therapy on insulin resistance (IR) and carbohydrate and lipid metabolism in postmenopausal women (PMW) with impaired (IGT) and normal glucose tolerance (NGT). METHODS: Sixteen Japanese PMW with IGT and 33 with NGT received daily oral hormone replacement therapy (HRT; 0.625 mg of conjugated equine estrogen plus 2.5 mg of medroxyprogesterone acetate) for 12 months. As controls, 13 Japanese PMW with IGT and 31 with NGT were enrolled and not treated by HRT. Fasting plasma glucose (FPG), fasting immunoreactive insulin (IRI), and IR were measured in each subject at study initiation and 12 months later. We used homeostasis model assessment (HOMA) to determine IR. RESULTS: FPG and HOMA IR were decreased in both HRT groups, and fasting IRI was reduced in the HRT-NGT group. In controls, FPG, fasting IRI, and HOMA IR were unaltered. Total and low-density lipoprotein cholesterol were decreased and high-density lipoprotein cholesterol was increased in both HRT groups, but triglyceride was unchanged. In controls, lipid metabolism was unaltered. CONCLUSION: HRT decreased IR and improved carbohydrate and lipid metabolism in Japanese PMW with IGT and NGT. These beneficial effects argue for the use of HRT in PMW with IGT as well as NGT.