ROCK2-induced metabolic rewiring in diabetic podocytopathy

Loss of podocytes is a common feature of diabetic renal injury and a key contributor to the development of albuminuria. We found that podocyte Rho associated coiled-coil containing protein kinase 2 (ROCK2) is activated in rodent models and patients with diabetes. Mice that lacked ROCK2 only in podocytes (PR2KO) were resistant to albuminuria, glomerular fibrosis, and podocyte loss in multiple animal models of diabetes (i.e., streptozotocin injection, db/db, and high-fat diet feeding). RNA-sequencing of ROCK2-null podocytes provided initial evidence suggesting ROCK2 as a regulator of cellular metabolism. In particular, ROCK2 serves as a suppressor of peroxisome proliferator-activated receptors α (PPARα), which rewires cellular programs to negatively control the transcription of genes involved in fatty acid oxidation and consequently induce podocyte apoptosis. These data establish ROCK2 as a nodal regulator of podocyte energy homeostasis and suggest this signaling pathway as a promising target for the treatment of diabetic podocytopathy.

ROCK2 is found to be activated in 3 diabetic models and patients with diabetes. ROCK2 deletion in podocytes protects against diabetic kidney injury, with the beneficial effect of ROCK2 inhibition observed due to rescued PPARα signaling, leading to a recovery of fatty acid metabolism.

ROCK Inhibition May Stop Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease and is strongly associated with cardiovascular mortality. Given the pandemic of obesity and diabetes, the elucidation of the molecular underpinnings of DKD and establishment of effective therapy are urgently required. Studies over the past decade have identified the activated renin-angiotensin system (RAS) and hemodynamic changes as important therapeutic targets. However, given the residual risk observed in patients treated with RAS inhibitors and/or sodium glucose co-transporter 2 inhibitors, the involvement of other molecular machinery is likely, and the elucidation of such pathways represents fertile ground for the development of novel strategies. Rho-kinase (ROCK) is a serine/threonine kinase that is under the control of small GTPase protein Rho. Many fundamental cellular processes, including migration, proliferation, and survival are orchestrated by ROCK through a mechanism involving cytoskeletal reorganization. From a pathological standpoint, several analyses provide compelling evidence supporting the hypothesis that ROCK is an important regulator of DKD that is highly pertinent to cardiovascular disease. In cell-based studies, ROCK is activated in response to a diverse array of external stimuli associated with diabetes, and renal ROCK activity is elevated in the context of type 1 and 2 diabetes. Experimental studies have demonstrated the efficacy of pharmacological or genetic inhibition of ROCK in the prevention of diabetes-related histological and functional abnormalities in the kidney. Through a bird’s eye view of ROCK in renal biology, the present review provides a conceptual framework that may be widely applicable to the pathological processes of multiple organs and illustrate novel therapeutic promise in diabetology.

ROCK2 regulates TGF-β-induced expression of CTGF and profibrotic genes via NF-κB and cytoskeleton dynamics in mesangial cells

The small GTPase Rho and its effector Rho kinase (ROCK) are involved in the pathogenesis of diabetic kidney disease. Rho kinase has two isoforms: ROCK1 and ROCK2. However, it remains unclear which is mainly involved in the progression of diabetic glomerulosclerosis and the regulation of profibrotic mediators. Glomeruli isolated from type 2 diabetic db/db mice demonstrated increased gene expression of transforming growth factor (TGF)-β and its downstream profibrotic mediators. Chemical inhibition of ROCK suppressed the expression of profibrotic mediators in both isolated glomeruli and cultured mesangial cells. An investigation of mechanisms underlying this observation revealed activated ROCK functions through the phosphorylation of JNK and Erk and the nuclear translocation of NF-κB via actin dynamics. Knockdown by siRNA against ROCK1 and ROCK2 showed that ROCK2 but not ROCK1 controls this fibrotic machinery. Further in vivo experiments showed that ROCK2 activity in the renal cortex of db/db mice was elevated compared with control db/m mice. Importantly, oral administration of ROCK2 inhibitor attenuated renal ROCK2 activity, albuminuria, and glomerular fibrosis in db/db mice. These observations indicate that ROCK2 is a key player in the development of diabetic renal injury. Glomerular ROCK2 may be a potential therapeutic target for the treatment of diabetic kidney disease.

Rho-Kinase Blockade Attenuates Podocyte Apoptosis by Inhibiting the Notch Signaling Pathway in Diabetic Nephropathy

Podocyte apoptosis is a key process in the onset of diabetic nephropathy. A significant body of evidence shows that the Notch signaling pathway plays a central role in this process. We found that Rho-kinase mediates transforming growth factor β (TGF-β)-induced Notch ligand Jag1 expression. Importantly, TGF-β-mediated podocyte apoptosis was attenuated by Rho-kinase inhibition. Mechanistically, Rho-kinase regulated Jag1 induction via the extracellular signal-regulated kinase (ERK) 1/2 and c-Jun N-terminal kinase (JNK) but not Smad pathways. Consistently, the Rho-kinase inhibitor fasudil prevented albuminuria and the urinary excretion of nephrin in db/db mice and reduced the prevalence of podocyte apoptosis and Jag1 expression. Finally, the expression of Jag1 and apoptosis markers such as Bax and cyclin-dependent kinase inhibitor 1A (CDKN1A) was decreased in podocytes derived from db/db mice treated with fasudil. The present study provides evidence that Rho-kinase plays a key role in podocyte apoptosis. Rho-kinase is an attractive therapeutic target for diabetic nephropathy.

MR Imaging of Hepatocellular Carcinoma

In order to clarify the factors contributing to the signal intensities (SIs) of HCC on T1-weighted images, the amount of water, lipid, copper (Cu), iron (Fe), and manganese (Mn) was determined in HCC and surrounding hepatic parenchyma of 13 patients. The relationships among these findings, the histopathologic findings, and the SIs of T1-weighted images were evaluated.

Among the 13 HCC, 3 had a high SI, 5 were isointense, and 5 had a low SI on T1-weighted images compared to the surrounding hepatic parenchyma. The paramagnetic ions which contributed to the SI patterns were assumed to be Cu in HCC (38.0±62.4 μg/g ww), and Fe in the liver (61.1±42.4 μg/g ww) and HCC (40.0±34.3 μg/g ww). In 8 HCC with high- or isointensity, 2 were grades I, 5 were grade II, and one was grade III according to the Edmondson-Steiner's histopathologic classification. It is concluded that the SI patterns alone can not be a sign of low grade malignancy because of the existence of Fe in livers and HCC.

Clinical Significance of the Champagne Bottle Neck Sign in the Extracranial Carotid Arteries of Patients with Moyamoya Disease

BACKGROUND AND PURPOSE

The champagne bottle neck sign represents a rapid reduction in the extracranial ICA diameters and is a characteristic feature of Moyamoya disease. However, the clinical significance of the champagne bottle neck sign is unclear. We investigated the relationship between the champagne bottle neck sign and the clinical and hemodynamic stages of Moyamoya disease.

MATERIALS AND METHODS

We analyzed 14 patients with Moyamoya disease before revascularization (5 men, 9 women; age, 43.2 ± 19.3 years). The ratio of the extracranial ICA and common carotid artery diameters was determined using carotid ultrasonography or cerebral angiography; a ratio of < 0.5 was considered champagne bottle neck sign-positive. The clinical disease stage was determined using the Suzuki angiographic grading system. CBF and cerebral vasoreactivity also were measured.

RESULTS

The ICA/common carotid artery ratio (expressed as median [interquartile range]) decreased as the clinical stage advanced (stages I-II, 0.71 [0.60-0.77]; stages III-IV, 0.49 [0.45-0.57]; stages V-VI, 0.38 [0.34-0.47]; P < .001). Lower ICA/common carotid artery ratio tended to occur in symptomatic versus asymptomatic arteries (0.47 [0.40-0.53] versus 0.57 [0.40-0.66], respectively; P = .06). Although the ICA/common carotid artery ratio was not related to cerebral perfusion, it decreased as cerebral vasoreactivity decreased (P < .01). All champagne bottle neck sign-positive arteries were classified as Suzuki stage ≥III, 73% were symptomatic, and 89% exhibited reduced cerebral vasoreactivity. In contrast, all champagne bottle neck sign-negative arteries were Suzuki stage ≤III, 67% were asymptomatic, and all showed preserved cerebral vasoreactivity.

CONCLUSIONS

The champagne bottle neck sign was related to advanced clinical stage, clinical symptoms, and impaired cerebral vasoreactivity. Thus, detection of the champagne bottle neck sign might be useful in determining the clinical and hemodynamic stages of Moyamoya disease.

Neurotrophic and neuroprotective properties of exendin-4 in adult rat dorsal root ganglion neurons: involvement of insulin and RhoA

Glucagon-like peptide-1 (GLP-1) is thought to preserve neurons and glia following axonal injury and neurodegenerative disorders. We investigated the neurotrophic and neuroprotective properties of exendin (Ex)-4, a synthetic GLP-1 receptor (GLP-1R) agonist, on adult rat dorsal root ganglion (DRG) neurons and PC12 cells. GLP-1R was predominantly localized on large and small peptidergic neurons in vivo and in vitro, suggesting the involvement of GLP-1 in both the large and small sensory fiber functions. Ex-4 dose-dependently (1 ≤ 10 ≤ 100 nM) promoted neurite outgrowth and neuronal survival at 2 and 7 days in culture, respectively. Treatment with 100 nM Ex-4 restored the reduced neurite outgrowth and viability of DRG neurons caused by the insulin removal from the medium and suppressed the activity of RhoA, an inhibitory regulator for peripheral nerve regeneration, in PC12 cells. Furthermore, these effects were attenuated by co-treatment with phosphatidylinositol-3'-phosphate kinase (PI3K) inhibitor, LY294002. These findings imply that Ex-4 enhances neurite outgrowth and neuronal survival through the activation of PI3K signaling pathway, which negatively regulates RhoA activity. Ex-4 and other GLP-1R agonists may compensate for the reduced insulin effects on neurons, thereby being beneficial for the treatment of diabetic neuropathy.

Measurement of the inclusive electron neutrino charged current cross section on carbon with the T2K near detector

The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ∼1  GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged ν(e) charged current cross section on carbon is measured to be ⟨σ⟩(ϕ)=1.11±0.10(stat)±0.18(syst)×10⁻³⁸ cm²/nucleon. The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23×10⁻³⁸ cm²/nucleon and the GENIE prediction is 1.08×10⁻³⁸ cm²/nucleon. The total ν(e) charged current cross-section result is also in agreement with data from the Gargamelle experiment.

Rho-kinase regulation of TNF-α-induced nuclear translocation of NF-κB RelA/p65 and M-CSF expression via p38 MAPK in mesangial cells

The small GTPase Rho and its downstream effector, Rho-associated coiled-coil containing protein kinase (Rho-kinase), regulate a number of cellular processes, including organization of the actin cytoskeleton, cell adhesion, and migration. While pharmacological inhibitors of Rho-kinase signaling are known to block renal inflammation, the molecular basis for this effect is unclear. Here, we provide evidence that proinflammatory TNF-α promotes mesangial expression of macrophage colony-stimulating factor (M-CSF), a key regulator for the growth and differentiation of mononuclear phagocytes, in a Rho-kinase-dependent manner. Consistent with this observation, TNF-α-mediated renal expression of M-CSF in insulin-resistant db/db mice was downregulated by Rho-kinase inhibition. Small interfering RNA-facilitated knockdown of Rho-kinase isoforms ROCK1 and ROCK2 indicated that both isoforms make comparable contributions to regulation of M-CSF expression in mesangial cells. From a mechanistic standpoint, Western blotting and EMSA showed that Rho-kinase and its downstream target p38 MAPK regulate nuclear translocation of NF-κB RelA/p65 and subsequent DNA binding activity, with no significant effects on IκBα degradation and RelA/p65 phosphorylation. Moreover, we showed that Rho-kinase-mediated cytoskeletal organization is required for the nuclear uptake of RelA/p65. Collectively, these findings identify Rho-kinase as a critical regulator of chemokine expression and macrophage proliferation.

Precise measurement of the neutrino mixing parameter θ23 from muon neutrino disappearance in an off-axis beam

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter θ23. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57×10(20) protons on target, T2K has fit the energy-dependent νμ oscillation probability to determine oscillation parameters. The 68% confidence limit on sin(2)(θ23) is 0.514(-0.056)(+0.055) (0.511±0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Δm32(2)=(2.51±0.10)×10(-3)  eV(2)/c(4) (inverted hierarchy: Δm13(2)=(2.48±0.10)×10(-3)  eV(2)/c(4)). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

Observation of electron neutrino appearance in a muon neutrino beam

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm(32)(2) and a CP violating phase δ(CP). In this neutrino oscillation scenario, assuming |Δm(32)(2)|=2.4×10(-3)  eV(2), sin(2)θ(23)=0.5, and Δm322>0 (Δm(32)(2)<0), a best-fit value of sin(2)2θ(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at δ(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of θ(13) from reactor experiments, some values of δ(CP) are disfavored at the 90% C.L.

Measurement of neutrino oscillation parameters from muon neutrino disappearance with an off-axis beam

The T2K Collaboration reports a precision measurement of muon neutrino disappearance with an off-axis neutrino beam with a peak energy of 0.6 GeV. Near detector measurements are used to constrain the neutrino flux and cross section parameters. The Super-Kamiokande far detector, which is 295 km downstream of the neutrino production target, collected data corresponding to 3.01×10(20) protons on target. In the absence of neutrino oscillations, 205±17 (syst) events are expected to be detected while only 58 muon neutrino event candidates are observed. A fit to the neutrino rate and energy spectrum, assuming three neutrino flavors and normal mass hierarchy yields a best-fit mixing angle sin2(θ23)=0.514±0.082 and mass splitting |Δm(32)(2)|=2.44(-0.15)(+0.17)×10(-3) eV2/c4. Our result corresponds to the maximal oscillation disappearance probability.

Preventive effect of nucleoprotein on hindlimb unloading-induced capillary regression in rat soleus muscle

We investigated the preventive effects of nucleoprotein on capillary regression and mitochondrial dysfunction induced by unloading in the soleus muscle of rats. Nucleoprotein is a supplement made from soft roe of salmon, and its major components are nucleotides and protamine. Adult male Sprague-Dawley rats were divided randomly into control, hindlimb unloading (HU), and hindlimb unloading plus nucleoprotein administration (HU+ NP) groups. Hindlimb unloading was carried out for 2 weeks in the rats belonging to the HU and the HU+ NP groups. The rats of the HU+ NP group were administered nucleoprotein (500 mg/kg) using a feeding needle twice a day for 2 weeks. Hindlimb unloading resulted in capillary regression, decreased succinate dehydrogenase activity of the muscle fiber, and decreased PGC-1α expression in the soleus muscle. These effects were prevented by administration of nucleoprotein. Nucleoprotein appears to prevent capillary regression and mitochondrial dysfunction caused by unloading of the skeletal muscle. Therefore, nucleoprotein supplementation may be an effective therapy for maintaining capillary network and mitochondrial metabolism of the muscle fiber during an unloading period.

Fasudil inhibits ER stress-induced VCAM-1 expression by modulating unfolded protein response in endothelial cells

The process of atherosclerosis is affected by interactions among numerous biological pathways. Accumulating evidence shows that endoplasmic reticulum (ER) stress plays a crucial role in the development of atherosclerosis. Rho-kinase is an effector of small GTP-binding protein Rho, and has been implicated as an atherogenic factor. Previous studies demonstrated that fasudil, a specific Rho-kinase inhibitor, exerts a cardioprotective effect by downregulating ER stress signaling. However, the molecular link between ER stress and Rho-kinase in endothelial cells has not been elucidated. In this study, we investigated the mechanisms by which fasudil regulates endothelial inflammation during ER stress. Tunicamycin, an established ER stress inducer, increased vascular cellular adhesion molecule (VCAM)-1 expression in endothelial cells. Intriguingly, fasudil inhibited VCAM-1 induction. From a mechanistic stand point, fasudil inhibited expression of activating transcription factor (ATF)4 and subsequent C/EBP homologous protein (CHOP) induction by tunicamycin. Furthermore, fasudil attenuated tunicamycin-induced phophorylation of p38MAPK that is crucial for the atherogenic response during ER stress. These findings indicate that Rho-kinase regulates ER stress-mediated VCAM-1 induction by ATF4- and p38MAPK-dependent signaling pathways. Rho-kinase inhibition by fasudil would be an important therapeutic approach against atherosclerosis, in particular, under conditions of ER stress.

Interactions between serum vitamin D levels and vitamin D receptor gene FokI polymorphisms for renal function in patients with type 2 diabetes

BACKGROUND

We aimed to examine associations among serum 25-hydroxyvitamin D (25OHD) levels, 1,25-dihyroxyvitamin D (1,25OHD) levels, vitamin D receptor (VDR) polymorphisms, and renal function based on estimated glomerular filtration rate (eGFR) in patients with type 2 diabetes.

METHODS

In a cross-sectional study of 410 patients, chronic kidney disease (CKD) stage assessed by eGFR was compared with 25OHD, 1,25OHD, and VDR FokI (rs10735810) polymorphisms by an ordered logistic regression model adjusted for the following confounders: disease duration, calendar month, use of angiotensin converting enzyme inhibitors/angiotensin receptor blockers or statins, and serum calcium, phosphate, and intact parathyroid hormone levels.

RESULTS

1,25OHD levels, rather than 25OHD levels, showed seasonal oscillations; peak levels were seen from May to October and the lowest levels were seen from December to February. These findings were evident in patients with CKD stage 3 ~ 5 but not stage 1 ~ 2. eGFR was in direct proportion to both 25OHD and 1,25OHD levels (P<0.0001), but it had stronger linearity with 1,25OHD (r = 0.73) than 25OHD (r = 0.22) levels. Using multivariate analysis, 1,25OHD levels (P<0.001), but not 25OHD levels, were negatively associated with CKD stage. Although FokI polymorphisms by themselves showed no significant associations with CKD stage, a significant interaction between 1,25OHD and FokITT was observed (P = 0.008). The positive association between 1,25OHD and eGFR was steeper in FokICT and CC polymorphisms (r = 0.74) than FokITT polymorphisms (r = 0.65).

CONCLUSIONS

These results suggest that higher 1,25OHD levels may be associated with better CKD stages in patients with type 2 diabetes and that this association was modified by FokI polymorphisms.

Haemoglobin A1c cut-off point to identify a high risk group of future diabetes: results from the Omiya MA Cohort Study

AIMS

Using the HbA(1c) level to define diabetes has several advantages and these advantages also apply to define a high-risk group. However, the risk of diabetes increases as HbA(1c) increases and a certain degree of arbitrariness in the cut-off for the high risk group is unavoidable. The aim of this study was to determine the HbA(1c) cut-off for defining a high-risk group that corresponds to the fasting plasma glucose cut-off by comparing the risk of diabetes against the fasting plasma glucose and HbA(1c) levels in the Japanese population.

METHODS

A retrospective cohort study was conducted using data from annual health examinations performed in Omiya city. A total of 11,271 subjects between the ages of 40 and 79 years without diabetes at baseline were followed for up to 7 years. According to the new diagnostic criteria, diabetes was defined as an fasting plasma glucose level ≥ 7 mmol/l or an HbA(1c) level ≥ 48 mmol/mol (≥ 6.5%) or a self-report. The HbA(1c) cut-off corresponding to the fasting plasma glucose cut-off was determined using the incidence, hazard ratio, and a receiver operating characteristic analysis.

RESULTS

Eight hundred and sixty subjects developed diabetes. The incidence, hazard ratio, and receiver operating characteristic analysis all indicated that an HbA(1c) cut-off of 39 mmol/mol (5.7%) corresponded to an fasting plasma glucose level of 5.6 mmol/l.

CONCLUSIONS

Our results suggested that the HbA(1c) cut-off for high-risk of diabetes should be 39 mmol/mol (5.7%), consistent with the American Diabetes Association recommendation. Further research is needed to determine whether our results are applicable to other populations.

Thrombin induces MCP-1 expression through Rho-kinase and subsequent p38MAPK/NF-κB signaling pathway activation in vascular endothelial cells

Thrombin has been shown to increase expression of chemokines such as monocyte chemoattractant protein 1 (MCP-1) in endothelial cells, leading to the development of atherosclerosis. However, the precise mechanism of this induction remains unknown. In the present study, we investigated whether the small G protein RhoA, and its effector, Rho-kinase are involved in MCP-1 induction by thrombin in endothelial cells. Y-27632, a specific Rho-kinase inhibitor, potently inhibited MCP-1 induction by thrombin. Y-27632 significantly decreased the chemotactic activity of thrombin-stimulated supernatants of endothelial cells on monocytes. Importantly, fasudil, a specific Rho-kinase inhibitor, attenuated MCP-1 gene expression in the aorta of db/db mice. Y-27632 attenuated thrombin-mediated phosphorylation of p38MAPK and p65, indicating that Rho-kinase mediates thrombin-induced MCP-1 expression through p38MAPK and NF-κB activation. Our findings demonstrate that the Rho/Rho-kinase signaling pathway plays a critical role in thrombin-mediated MCP-1 expression and function, and suggest that Rho/Rho-kinase may be an important target in the development of new therapeutic strategies for atherosclerosis.

Lower osteocalcin and osteopontin contents of the femoral head in hip fracture patients than osteoarthritis patients

In patients with femoral neck fracture, clinical factors, bone metabolism markers (in serum, urine, and bone), bone mineral density, radiographic parameters, and bone histomorphometric parameters were investigated to detect determinants of fragility fracture. The osteocalcin/deoxypyridinoline ratio and osteopontin/calcium ratio of cortical bone were selected as significant predictors.

INTRODUCTION

Measurement of bone mineral density is widely used to assess bone strength, but this also depends on other bone components and on bone structure. The objective of this study was to investigate risk factors for fracture related to bone quality, the patient's history, and the patient's lifestyle.

METHODS

Twenty-one patients with femoral neck fracture and 18 patients with osteoarthritis were enrolled. Blood and urine samples were collected on admission to hospital, and bone samples were obtained from femoral necks resected during surgery. Multivariate logistic regression analysis was performed using osteoarthritis and femoral neck fracture as combined variables to assess the influence of alcohol or coffee intake, eating natto (fermented soybeans), osteocalcin and calcium concentrations, the osteocalcin/deoxypyridinoline ratio and osteopontin/calcium ratios of cortical bone and cancellous bone, various bone histomorphometric parameters, the bone mineral density of the lumbar spine and the intact contralateral femoral neck, and various radiographic parameters of the spine

RESULTS

By forward stepwise multivariate analysis, the osteocalcin/deoxypyridinoline and osteopontin/calcium ratios of cortical bone were selected as significant factors for fracture (the odds ratios were 0.493 and <0.001, respectively; both P<0.001).

CONCLUSIONS

A decrease of osteopontin and osteocalcin in bone is important for promoting vulnerability to hip fracture.

Association of polymorphism of estrogen receptor-alpha gene with circulating levels of adiponectin in postmenopausal women with type 2 diabetes

AIM

Menopause is a risk factor for cardiovascular disease (CVD) in women because of the reduction in endogenous estrogen. Recently, single nucleotide polymorphisms (SNPs) of the estrogen receptor alpha (ESR-1) gene (c.454-397T>C) associated with the prognosis of myocardial infarction in postmenopausal women were identified; however, the mechanism by which genetic variation of ESR-1 contributes to the pathogenesis of CVD is unknown. Circulating levels of adipokines and inflammatory cytokines predict CVD risk; hence, this study aimed to investigate whether ESR-1 genotypes (c.454-397T>C) might influence circulating levels of adipokines and inflammatory cytokines in postmenopausal women with type 2 diabetes.

METHODS

Sixty-three postmenopausal women with type 2 diabetes were recruited. Serum levels of adiponectin, resistin, interleukin-6 (IL-6), and high-sensitive C-reactive protein (hs-CRP) were determined.

RESULTS

The genotype of ESR-1 was closely associated with serum adiponectin, which was decreased in subjects with the T allele and was lowest in those with the T/T genotype. Multiple logistic regression analysis revealed independent contribution of the homozygote for the T allele to low serum levels of adiponectin.

CONCLUSION

The T allele of the c.454-397T>C SNP of ESR-1 is associated with low serum levels of adiponectin, which may lead to a high risk of CVD in postmenopausal women.

Heating properties of the needle type applicator made of shape memory alloy by 3-D anatomical human head model

Since the human brain is protected by the skull, it is not easy to non-invasively heat deep brain tumors with electromagnetic energy for hyperthermia treatments. Generally, needle type applicators were used in clinical practice to heat brain tumors. To expand the heating area of needle type applicators, we have developed a new type of needle made of a shape memory alloy (SMA). In this paper, heating properties of the proposed SMA needle type applicator were discussed. Here, in order to apply the SMA needle type applicator clinically. First, we constructed an anatomical 3-D FEM model from MRI and X-ray CT images using 3D-CAD software. Second, we estimated electric and temperature distributions to confirm the SMA needle type applicator using the FEM soft were JMAG-Studio. From these results, it was confirmed that the proposed method can expand the heating area and control the heating of various sizes of brain tumors.

Association of urinary albumin excretion with insulin resistance in Japanese subjects: impact of gender difference on insulin resistance

OBJECTIVE

To investigate the relationship between homeostasis model assessment for insulin resistance (HOMA-R) and urinary albumin excretion in Japanese and clarify gender difference in albuminuria-related insulin resistance.

METHODS

The subject group consisted of 752 Japanese who had no history of diabetes, hypertension or dyslipidemia. After anthropometric examination, fasting blood samples were obtained to determine plasma glucose (FPG), lipids and HOMA-R. The urinary excretion of albumin in the first void urine was expressed as the creatinine ratio (ACR, mg/gCr). Estimated glomerular filtration rate (eGFR) was calculated from serum creatinine using the formula for Japanese.

RESULTS

HOMA-R showed a significant correlation with ACR, and the correlation between HOMA-R and ACR was evident in the subjects with central obesity, whereas no significant correlation was found in the non-obese subjects. There was no correlation between HOMA-R and eGFR. HOMA-R increased according to the quintile of ACR and followed a significant trend. This association was obvious in males; however, in females there was no significant trend. Multiple regression analysis revealed that HOMA-R showed a significant correlation with age, waist circumference, blood pressure and serum triglyceride. In addition, ACR exhibited an independent association with HOMA-R. The association of HOMA-R and ACR was observed only in males, and was not present in females.

CONCLUSION

Microalbuminuria is associated with insulin resistance in Japanese, where central obesity might play an essential role. This association is gender-specific suggesting the involvement of sex hormones in the pathogenesis of albuminuria-related insulin resistance.

Degradation of PEP-19, a calmodulin-binding protein, by calpain is implicated in neuronal cell death induced by intracellular Ca2+ overload

Excessive elevation of intracellular Ca2+ levels and, subsequently, hyperactivation of Ca2+/calmodulin-dependent processes might play an important role in the pathologic events following cerebral ischemia. PEP-19 is a neuronally expressed polypeptide that acts as an endogenous negative regulator of calmodulin by inhibiting the association of calmodulin with enzymes and other proteins. The aims of the present study were to investigate the effect of PEP-19 overexpression on cell death triggered by Ca2+ overload and how the polypeptide levels are affected by glutamate-induced excitotoxicity and cerebral ischemia. Expression of PEP-19 in HEK293T cells suppressed calmodulin-dependent signaling and protected against cell death elicited by Ca2+ ionophore. Likewise, primary cortical neurons overexpressing PEP-19 became resistant to glutamate-induced cell death. In immunoprecipitation assay, wild type PEP-19 associated with calmodulin, whereas mutated PEP-19, which contains mutations within the calmodulin binding site of PEP-19, failed to associate with calmodulin. We found that the mutation abrogates both the ability to suppress calmodulin-dependent signaling and to protect cells from death. Additionally, the endogenous PEP-19 levels in neurons were significantly reduced following glutamate exposure, this reduction precedes neuronal cell death and can be blocked by treatment with calpain inhibitors. These data suggest that PEP-19 is a substrate for calpain, and that the decreased PEP-19 levels result from its degradation by calpain. A similar reduction of PEP-19 also occurred in the hippocampus of gerbils subjected to transient global ischemia. In contrast to the reduction in PEP-19, no changes in calmodulin occurred following excitotoxicity, suggesting the loss of negative regulation of calmodulin by PEP-19. Taken together, these results provide evidence that PEP-19 overexpression enhances resistance to Ca2+-mediated cytotoxicity, which might be mediated through calmodulin inhibition, and also raises the possibility that PEP-19 degradation by calpain might produce an aberrant activation of calmodulin functions, which in turn causes neuronal cell death.

Finite element analysis of the needle type applicator made of shape memory alloy

In this paper, we propose a new heating method in which we use shape memory alloy (SMA) in a needle type applicator for brain tumor hyperthermia. In order to expand the heating area of a needle type applicator and to control the heating pattern for various sizes of tumors, some kinds of SMA needle type applicators were developed. To apply the proposed heating method safely to clinical hyperthermia, it is necessary to make appropriate thermal distribution to the region of the brain tumor. However, it is not easy to predict the three dimensional temperature distribution during the human brain tumor hyperthermia. Therefore, we estimated the temperature distribution inside the agar phantom by the finite element method (FEM). Here, first, the computer simulation results of temperature distributions under the different heating times are discussed. Second, a comparison of the heating properties obtained by using the needle type electrodes made of different shaped SMA is discussed. From these results, it is confirmed that the proposed heating method can expand the heating area and control the heating pattern for the various sizes of brain tumors.

Improvement of needle type applicator made of shape memory alloy

This paper discusses radio frequency (RF) interstitial hyperthermia for brain tumors with a developed needle type applicator made of a shape memory alloy (SMA). The problem with the heating method of interstitial hyperthermia is the small heating area. So, we proposed a new heating method using a needle type electrode made of SMA which consists of nickel (Ni), copper (Cu) and titanium (Ti) for expanding the heating area. Here, we proposed the heating method that the leading end of needle type electrode was divided into four parts and the leading end spreads in four directions with a temperature rise. First, the proposed RF interstitial hyperthermia system with the SMA needle was presented. Second, the results obtained by the experimental heating of the agar phantom by using the developed SMA needle type applicator were presented. Third, comparing experimental results, we discussed the heating properties of the developed system. Finally, from these results, it is confirmed that the developed needle type applicator made of SMA is useful for wide heating by invasive hyperthermia.

The Rho-kinase inhibitor, fasudil, attenuates diabetic nephropathy in streptozotocin-induced diabetic rats

This study aimed to investigate the effect of the Rho-kinase inhibitor fasudil on the development of diabetic nephropathy and clarify a contribution of the Rho/Rho-kinase pathway to the pathogenesis of diabetic nephropathy. Diabetes was induced in male Sprague-Dawley rats with an intraperitoneal injection of streptozotocin. Animals were then divided into the following 4 groups; normal control rats, diabetic rats, diabetic rats administered fasudil orally and diabetic rats administered fluvastatin (3-hydroxy-methylglutaryl coenzyme A reductase inhibitor, statin) orally. After 1 month of treatment, neither fasudil nor statin had any influence on blood glucose or blood pressure in diabetic rats. While urinary excretion of albumin and 8-hydroxydeoxyguanosine (8-OHdG) was increased in diabetic rats, both of these increases were abolished by fasudil and statin. Rho activity was enhanced in the renal cortex of diabetic rats compared to normal controls, and this enhancement was abolished by statin treatment. Expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) mRNA was up-regulated in the renal cortex of diabetic rats, and this was abolished by fasudil as well as statin. Expression of NOX4 mRNA (catalytic subunit of NAD(P)H oxidase) was up-regulated in the renal cortex of diabetic rats, an effect which was also abolished by fasudil as well as statin. The present study demonstrates that the Rho/Rho-kinase pathway is involved in up-regulation of TGF-beta, CTGF and NAD(P)H oxidase in diabetic kidney. We conclude that suppression of the Rho/Rho-kinase pathway could be a new strategy for the treatment of diabetic nephropathy.

Heating properties of developed needle type applicator made of shape memory alloy

This paper discusses radio frequency (RF) interstitial hyperthermia for a brain tumor with a needle type applicator made of a shape memory alloy (SMA). In this method, it is necessary to make appropriate thermal distribution to the region of the brain tumor. However, it is not easy to predict the thermal distribution during the heating. We estimated the temperature distribution inside an agar phantom by the finite element method (FEM), and heated the agar phantom with the developed needle type applicator. Here, first, the developed RF interstitial hyperthermia system with the SMA needle was presented. Second, the results obtained by the computer simulation and the experimental heating results of the agar phantom by using the developed SMA needle type applicator were presented. Comparing computer simulation results and experimental results, we discussed the heating properties of the developed system. Finally, from these results, it is confirmed that the developed needle type applicator made of SMA is useful for wide heating of invasive hyperthermia.

Transforming growth Factor–Beta signaling is enhanced following Mitomycin-C treatment of islet xenograft

Mitomycin-C (MMC) is categorized as an agent that causes genotoxic stress by triggering various intracellular signaling pathways. We have previously shown that MMC pretreatment of highly immunogenic crude islets leads to significant prolongation of graft survival in a rat-to-mouse model. In the present study, we examined whether TH1/TH2 cytokine, including the inflammatory cytokines interferon-gamma and interleukin (IL)-2, or the Th2 group, IL-4, IL-10, TNF-alpha, IL-1 beta, IL-6, GM-CSF, and transforming growth factor (TGF)-beta were up-regulated or down-regulated following MMC treatment of islets. We found changes in TGF-beta messenger RNA (mRNA) transcription as the only events among the measured cytokines. TGF-beta concentration was elevated in blebs formed under the kidney capsule, but not in the serum or ascites among animals given MMC-treated islets than in animals given untreated islets, suggesting local processes induced by MMC might inhibit xenograft rejection.

Characteristics of pancreas transplantation currently performed in japan

The Pancreas Transplantation (tx) Program under the Japanese Organ Transplant Act was started in 2000. PTx is indicated for type 1 diabetic patients on hemodialysis therapy. As of April 2003 93 patients are listed as candidates. Ten cases of PTx with enteric or bladder-drained technique were performed during the last 3 years as well as nine SPK and one PAK. Of 10 cases, nine recipients are insulin-free with HbA1c values ranging from 4.4% to 5.7%, although exogenous insulin was required in six cases temporarily, namely for a median 63 days (12 to 225 days). One case was lost due to pancreatic graft thrombosis. All 10 kidney grafts are functioning. Based on the experiences with 14 cases of pancreas tx using non-heart-beating (NHB) donors, we defined the criteria of NHB donor as: age younger than 40 years and cessation of respiratory support. One case of SPK with graft of NHB donor was done, and the recipient is off insulin. Pancreas and kidney are allocated for SPK if the recipient shares at least one HLA-DR antigen. Marginal donors were defined as higher mean donor age, median 37 (range 18 to 58 years); mean 38 +/- 12 years), and no death cause of by trauma. The revascularization of gastroduodenal artery to the pancreatic graft was performed in eight cases to minimize the risk of ischemic injury to the pancreatic graft and technical failure in cases of marginal donor.

Pancreas-kidney transplantation in Japan: impact of cyclosporine on the development of immunosuppressive therapy

The number of pancreas transplants reached 16,043 worldwide in October 2001, with 1800 performed in 2000. Since the introduction of cyclosporine (CyA) in 1979, a regimen consisting of CyA, azathioprine, and steroids has been shown to improve long-term survival of clinical transplants. In Japan, the first simultaneous pancreas-kidney transplantation was performed in 1984, using organs from a brain-dead donor. This procedure was followed by 14 pancreas transplantations from cardiac arrest donors. All cases utilized a CyA-based regimen with antilymphocyte globulin or OKT3 induction. Six of the 15 recipients required less insulin postoperatively. Under a new transplant law enforced in 1997, 10 pancreas/pancreas-kidney transplantations were performed in patients diagnosed with end-stage renal failure due to diabetes mellitus type 1. In 1 patient, the graft failed due to venous thrombosis, but the other 9 recipients achieved an increased quality of life without the need for insulin or for dialysis. Pancreas transplantation represents an effective treatment worldwide and in Japan, due to the availability of CyA or tacrolimus in combination with other agents such as antilymphocyte globulin, OKT3, or mycophenolate mofetil. This investigation presents the results of pancreas-kidney transplantation in Japan, in comparison with those worldwide, and describes a recent case in Japan.

Telescience testbed experiments of intracellular recordings in the Xenopus oocyte

The feasibility of intracellular recordings under constraints for experimental conditions in outer space were tested at a telescience testbed of the National Space Development Agency of Japan. We attempted to study the dose-response relationship of adenosine-induced potential changes in the Xenopus oocyte. The testbed simulated the distance from a ground control room to oocytes in an orbital laboratory; signals were delayed and compressed from one "station" to other. A microelectrode was inserted into the oocyte using remote control on the manipulator and on the xyz-planes of the platform with stereoscopic pictures observed through a head mounted display. When the transfer rate of the visual signals was decreased from 1.5 Mbps to 128 Kbps, insertion of the electrode became almost impossible because of reduced picture quality. Once the electrode was inserted, however, dose-dependent adenosine responses could be observed with little trouble.

Antibodies to GAD in Japanese patients classified as Type 2 diabetes at diagnosis. High titre of GAD Ab is a predictive marker for early insulin treatment--report of west Japan (Kyushu, Yamaguchi, Osaka) study for GAD Ab(+) diabetes

AIM

We evaluated the prevalence of GAD Ab in Japanese Type 2 diabetic patients treated with oral hypoglycaemic agents (OHA) and/or diet and followed GAD Ab(+) patients to assess the usefulness of GAD Ab as a marker for future insulin treatment prospectively.

METHODS

A total of 2658 Japanese Type 2 diabetic patients treated by OHA and/or diet were randomly selected between April 1996 and December 1998. The clinical characteristics at entry were assessed and patients were followed for 1-3 years.

RESULTS

The overall prevalence of GAD Ab among Type 2 diabetic patients was 2.0%. Forty-five had a history of diabetes of < or = 5 years (short history) while those with duration > 5 years (long history) totalled nine. Among them, 47% of patients with a short history did not require insulin in the follow-up period. However, none of those with a long history required insulin treatment within 2 years. Comparison of patients based on GAD titre in those with short history showed that 33% of patients in the high-titre group (> or = 20 U) required no insulin treatment in the first year of follow-up. In contrast, this proportion was 80% in the first and 67% in the second year in the low-titre group (< 20 U).

CONCLUSIONS

The prevalence of GAD Ab in Japanese patients with a short and long history of diabetes was 2.8% and 0.9%, respectively. The presence of GAD Ab in Japanese Type 2 diabetic patients with a short history of diabetes is a marker for early insulin treatment.

A case of apolipoprotein C-II deficiency with coronary artery disease

A 56-year-old male with apolipoprotein C-II deficiency experienced a myocardial infarction without pancreatitis. A coronary angiogram showed complete occlusions of both the right and circumflex coronary arteries. His serum lipid levels were as follows: fasting total cholesterol 3.15 mmol/l; postprandial total cholesterol 3.62 mmol/l; fasting triglycerides 1.46 mmol/A; postprandial triglycerides 6.14 mmol/l; fasting high-density lipoprotein-cholesterol 0.47 mmol/l; and postprandial high-density lipoprotein cholesterol 0.36 mmol/l. His fasting level of plasma apolipoprotein C-II was 0.005 g/l, but his plasma levels of other apolipoproteins were within normal ranges. A DNA sequence analysis of the apolipoprotein C-II gene showed no mutations in exon 1, 2, 3, or 4, where most gene mutations related to apolipoprotein C-II deficiency occur. We report this patient's very rare heterozygous apolipoprotein C-II deficiency with coronary artery disease. Although this patient had some risk factors for coronary artery disease, coronary atherosclerosis in this patient might have occurred as a result of lipoprotein abnormalities caused by at least one mutation in the apolipoprotein C-II gene.