Development and validation of a scoring system for prediction of insulin requirement for optimal control of blood glucose during glucocorticoid treatments.

AIMS: We have developed and validated a novel scoring system to predict insulin requirement for optimal control of blood glucose during glucocorticoid (GC) treatments, by retrospective analyses of clinical parameters before GC treatment. METHODS: Three hundred-three adults (the Developing set) undergoing their first treatment of prednisolone (PSL) were divided into two groups, depending on treatment with or without insulin. Independent risk factors for insulin requirement were identified by a stepwise logistic regression analysis after univariate analyses between the two groups. We constructed a point-addition scoring system consisting of several categories and their coefficients in each risk factor derived from another logistic regression analysis. We validated it to two validation sets, A and B. RESULTS: Male, higher levels of fasting plasma glucose (FPG), HbA1c, and serum creatinine (CRE) and a higher initial dose of PSL were identified as the risk factors. The sensitivity, specificity, and accuracy were 90.0%, 88.1%, and 88.4%; 87.5%, 66.7%, and 70.5%; 83.3%, 76.1%, and 76.6% in the Developing set, Validation set A, and Validation set B, respectively, when the scoring system was applied. CONCLUSIONS: The scoring system is a valid and reliable tool to predict insulin requirements in advance during GC treatment.

TAFRO syndrome: 2 cases and review of the literature.

Recently, more than ten cases of thrombocytopenia, anasarca, fever, reticulin fibrosis, and organomegaly (TAFRO) syndrome or Castleman-Kojima disease exhibiting such symptoms as thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly have been reported in Japan. We have found two cases of TAFRO syndrome and have reviewed another eighteen previously reported cases. Histological findings of the lymph nodes and levels of interleukin 6 (IL-6) and vascular endothelial growth factor in both serum/plasma and effusions are important characteristics for diagnosing this syndrome.

Blockade of Sphingosine 1-Phosphate Receptor 2 Signaling Attenuates High-Fat Diet-Induced Adipocyte Hypertrophy and Systemic Glucose Intolerance in Mice.

Sphingosine 1-phosphate (S1P) is known to regulate insulin resistance in hepatocytes, skeletal muscle cells, and pancreatic ß-cells. Among its 5 cognate receptors (S1pr1-S1pr5), S1P seems to counteract insulin signaling and confer insulin resistance via S1pr2 in these cells. S1P may also regulate insulin resistance in adipocytes, but the S1pr subtype(s) involved remains unknown. Here, we investigated systemic glucose/insulin tolerance and phenotypes of epididymal adipocytes in high-fat diet (HFD)-fed wild-type and S1pr2-deficient (S1pr2(-/-)) mice. Adult S1pr2(-/-) mice displayed smaller body/epididymal fat tissue weights, but the differences became negligible after 4 weeks with HFD. However, HFD-fed S1pr2(-/-) mice displayed better scores in glucose/insulin tolerance tests and had smaller epididymal adipocytes that expressed higher levels of proliferating cell nuclear antigen than wild-type mice. Next, proliferation/differentiation of 3T3-L1 and 3T3-F442A preadipocytes were examined in the presence of various S1pr antagonists: JTE-013 (S1pr2 antagonist), VPC-23019 (S1pr1/S1pr3 antagonist), and CYM-50358 (S1pr4 antagonist). S1P or JTE-013 treatment of 3T3-L1 preadipocytes potently activated their proliferation and Erk phosphorylation, whereas VPC-23019 inhibited both of these processes, and CYM-50358 had no effects. In contrast, S1P or JTE-013 treatment inhibited adipogenic differentiation of 3T3-F442A preadipocytes, whereas VPC-23019 activated it. The small interfering RNA knockdown of S1pr2 promoted proliferation and inhibited differentiation of 3T3-F442A preadipocytes, whereas that of S1pr1 acted oppositely. Moreover, oral JTE-013 administration improved glucose tolerance/insulin sensitivity in ob/ob mice. Taken together, S1pr2 blockade induced proliferation but suppressed differentiation of (pre)adipocytes both in vivo and in vitro, highlighting a novel therapeutic approach for obesity/type 2 diabetes.

Impaired ß-cell function attenuates training effects by reducing the increase in heart rate reserve in patients with myocardial infarction.

BACKGROUND: Insulin resistance (IR) is characterized as a metabolic disorder syndrome that is upstream of hypertension, dyslipidemia, and diabetes mellitus (DM). This study investigated exercise training effects on the exercise tolerance and heart rate dynamics in patients with IR or pancreatic ß-cell dysfunction. METHODS: Seventy patients (mean age, 60.1 years) with myocardial infarction (MI) participating in a phase II cardiac rehabilitation program were studied. Patients diagnosed with DM were excluded. Homeostasis model-assessment indices were used to divide patients into three groups - A: IR; B: normal; and C: ß-cell dysfunction. A cardiopulmonary exercise test (CPX) was performed and peak oxygen uptake (V˙O2) was measured. After baseline testing, subjects participated in a supervised, combined aerobic and resistance exercise program. RESULTS: Peak V˙O2 at baseline was comparable among the three groups, and it improved after training in all groups (p<0.05). However, both the increase and percentage increase in peak V˙O2 were smaller in Group C than in Group A (p<0.05). Heart rate (HR) reserve (peak HR-rest HR), and HR recovery immediately 1min after exercise during CPX were calculated in 45 patients who were not taking negative chronotropic agents. Group C alone did not show any significant increase in HR reserve. HR reserve at both baseline and after training had significant positive correlations with peak V˙O2. HR recovery was 1.9 beats/min lower in group C than group A, but this was not significant. HR recovery in group C did not increase after cardiac rehabilitation. CONCLUSION: Impaired HR reserve increase after training in patients with pancreatic ß-cell dysfunction attenuates exercise training effects on functional capacity. Comprehensive treatment including vigorous exercise training will be needed in such prediabetic patients.

Successful natural interferon-ß plus ribavirin therapy in a chronic hepatitis C patient after discontinuation of interferon-α treatment due to arrhythmia and interstitial pneumonia.

A 71-year-old female patient with hepatitis C virus genotype 1 had previously discontinued interferon (IFN)-α plus ribavirin therapy, pegylated IFN-α (pegIFN-α) monotherapy, and natural IFN-α monotherapy because of arrhythmia, interstitial pneumonia, and severe neurovegetative symptoms. She subsequently completed 72 weeks of natural IFN-ß plus ribavirin therapy without remarkable adverse effects and achieved a sustained viral response, suggesting differences in the pharmacological properties and biological effects of IFN-α and IFN-ß. Thus, natural IFN-ß plus ribavirin therapy may be a treatment option for patients with poor tolerance to IFN-α or pegIFN-α treatments.

Effect of nematode Trichinella infection on glucose tolerance and status of macrophage in obese mice.

We investigated the effect of Trichinella infection on glucose tolerance and (pro- or anti-inflammatory) macrophage status in adipose tissue. Ob/ob mice and high fat-fed mice (obesity model) and C57/BL mice (control mice) were orally infected with (infected group) or without (uninfected group) 400 Trichinella per mouse. Four weeks later, the mice were subjected to investigation, which showed that fasting plasma glucose levels decreased in the infected group of C57/BL and ob/ob mice. Glucose tolerance, evaluated with intraperitoneal GTT, improved in the infected group of ob/ob mice and high fat-fed mice compared with the uninfected groups. Additional assay included anti-inflammatory macrophage (M2) markers and pro-inflammatory macrophage (M1) markers, with the aim to explore the effect of Trichinella infection on adipose tissue inflammation, since our previous study identified anti-inflammatory substances in secreted proteins by Trichinella. The result showed that mRNA levels of M2 markers, such as CD206, arginase and IL-10, increased, whereas M1 markers, such as CD11c, iNOS and IL-6, decreased in the stromal vascular fraction (SVF) isolated from epididymal fat in ob/ob mice. Residential macrophages obtained from the peritoneal lavage exhibited lower M1 markers and higher M2 markers levels in the infected group than in the uninfected group. Trichinella infection increases the ratio of M2/M1 systemically, which results in an improvement in pro-inflammatory state in adipose tissue and amelioration of glucose tolerance in obese mice.

The role of small proliferative adipocytes in the development of obesity: comparison between Otsuka Long-Evans Tokushima Fatty (OLETF) rats and non-obese Long-Evans Tokushima Otsuka (LETO) rats.

Obesity consists of hypertrophy and hyperplasia of adipocytes. Although the number of adipocytes is influenced by anatomical location, nutritional environment, hormone and genetic variation, it has been thought to be determined by the proliferation of precursor cells and subsequent differentiation. However, our recent research has identified the population of small adipocytes less than 20 µm in diameter, exhibiting tiny or no lipid droplets and expressing adipocyte marker proteins (small proliferative adipocytes: SPA) in isolated adipocytes. Notably, 5-bromo-2'-deoxyuridine (BrdU) incorporation and proliferating cell nuclear antigen (PCNA) expression were detected in these cells. In this study, we investigated the role of SPA in development of adipose tissue using genetically obese diabetic Otsuka Long-Evans Tokushima Fatty (OLETF) rats and their non-obese and non-diabetic littermates, Long-Evans Tokushima Otsuka (LETO) rats. Proliferation of SPA was determined by measurement of PCNA at the protein level in isolated fractions of adipocytes with collagenase digestion. In general, expression levels of PCNA rose, reached a maximum, and declined in adipose tissues during aging. The expression levels of PCNA were maximum in epididymal fat at 32 w and 12 w of age in LETO and OLETF, respectively. They reached the maximum at 20 w of age both in LETO and OLETF in mesenteric fat. Although the PCNA expression level was higher in OLETF in the early period, it reversed later. Enlargement of adipocytes developed during aging, which was enhanced when the expression levels of PCNA declined. These results suggest that proliferation of SPA may prevent adipocyte hypertrophy and the resultant development of metabolic disorders.

Small proliferative adipocytes: identification of proliferative cells expressing adipocyte markers.

It has been thought that adipocytes lack proliferative ability and do not revert to precursor cells. However, numerous findings that challenge this notion have also been reported. The idea that adipocytes dedifferentiate to fibroblast-like cells with increasing cell number was reported in 1975. This possibility has been ignored despite knowledge gained in the 1990s regarding adipocyte differentiation. Several studies on proliferation and dedifferentiation of adipocytes have been published, most of which were conducted from the perspective of regenerative medicine. However, the concept of proliferation of adipocytes remains unclear. In this study, we postulate a new population of adipocytes, which consist of small sized cells (less than 20 µm in diameter) expressing adipocyte markers, such as adiponectin and peroxisome proliferator-activated receptor γ (PPARγ), but not possessing large lipid droplets. These cells show marked ability to incorporate 5-bromo-2'-deoxyuridine (BrdU), for which reason we termed them "small proliferative adipocytes (SPA)". In addition, SPA are observed in the stromal vascular fraction. Since SPA are morphologically different from mature adipocytes, we regarded them as committed progenitor cells. When proliferation of adipocytes in vivo is assessed by measuring BrdU incorporation and expression levels of proliferating cell nuclear antigen (PCNA) in isolated fractions of adipocytes from adipose tissues, subcutaneous SPA proliferate less actively than visceral SPA. Treatment with pioglitazone increases the number of proliferating SPA in subcutaneous, but not visceral, fat, suggesting that SPA may be important in regulating systemic insulin sensitivity and glucose metabolism.

Localization of multidomain adaptor proteins, p140Cap and vinexin, in the pancreatic islet of a spontaneous diabetes mellitus model, Otsuka Long-Evans Tokushima Fatty rats.

We have shown that two multidomain adaptor proteins, p140Cap and vinexin, interact with each other and are likely to be involved in neurotransmitter release. Because the basic molecular mechanism governing neurotransmitter and insulin secretion is conserved, these two proteins may also to play pivotal roles in insulin secretion. We therefore performed some characterization of p140Cap and vinexin in pancreas of a wild-type rat or a spontaneous type 2 diabetes mellitus (DM) model, the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. These two proteins were detected in Wistar rat pancreas by Western blotting. Immunohistochemistry revealed that p140Cap and vinexin are enriched in ß and α cells, respectively, in the rat pancreas. We then found that pancreatic islet structure was disorganized in the OLETF rat with hyperinsulinemia or with hyperglycemia, based on immunohistochemical analyses of vinexin. In ß cells of these model rats, p140Cap was distributed in a cytoplasmic granular pattern as in the control rats, although its expression was reduced to various extents from cell to cell. These results may suggest possible involvement of p140Cap in insulin secretion, and reduction of p140Cap might be related to abnormal insulin secretion in DM.

Pioglitazone enhances small-sized adipocyte proliferation in subcutaneous adipose tissue.

The possibility that mature adipocytes proliferate has not been fully investigated. In this study, we demonstrate that adipocytes can proliferate. 5-bromo-2'-deoxyuridine (BrdU)-labeled adipocyte like cells, most of which were less than 30 µm in diameter, were observed in adipose tissue. Proliferating cell nuclear antigen (PCNA) was simultaneously detected in BrdU-labeled nuclei. Observation of individual mature adipocytes of smeared specimens on glass slides revealed that small sized adipocytes more frequently incorporated BrdU. Cultured mature adipocytes using the ceiling-cultured method showed clustering of proliferating cells in small-sized adipocytes. These small cultured adipocytes, but not large ones, extensively incorporated BrdU. Quantified analysis of BrdU incorporation demonstrated that mature visceral adipocytes, including epididymal, mesenteric and perirenal adipocytes, proliferated more actively than subcutaneous ones. On the other hand, treatment with pioglitazone (Pio), a ligand of peroxisome proliferator-activated receptor γ, containing food for 2w, elevated BrdU incorporation and expression of PCNA in mature adipocytes isolated from subcutaneous, but not visceral adipose tissue. Moreover, Pio induced increased BrdU-labeled small-sized subcutaneous adipocytes, which was associated with an increased number of total small adipocytes in subcutaneous adipose tissue. In conclusion, mature adipocytes have a subgroup representing the potential to replicate, and this proliferation is more active in visceral adipocytes. Treatment with Pio increases proliferation in subcutaneous adipocytes. These results may explain the mechanism of Pio-induced hyperplasia especially in subcutaneous adipocytes.

Dehydroepiandrosterone reduces preadipocyte proliferation via androgen receptor.

Several studies have suggested that both testosterone and dehydroepiandrosterone (DHEA) have weight-reducing and antidiabetic effects, especially in rodent studies; however, the precise mechanism of their action remains unclear. Here, we investigated the effect of DHEA on cell growth in adipose tissue. The appearance of senescence-associated ß-galactosidase in stromal vascular fraction (SVF) isolated from Otsuka Long-Evans Tokushima fatty rats, an animal model of inherent obese type 2 diabetes, was prevented by DHEA administration. Next, the effects of DHEA and testosterone were compared in vivo and in vitro to evaluate whether these hormones influence cell growth in adipose tissue. Both DHEA and testosterone reduced body weight and epididymal fat weight equivalently when administered for 4 wk. To assess the effect of DHEA and testosterone on cell growth in adipose tissue, 5-bromo-2'-deoxyuridine (BrdU) uptake by SVF was measured. Quantification analysis of BrdU uptake by examining DNA isolated from each SVF revealed that treatment with DHEA and testosterone reduced cell replication. These results indicated that DHEA- and testosterone-induced decreased adiposity was associated with reduced SVF growth. Incubation with DHEA and testosterone equally decreased BrdU uptake by 3T3-L1 preadipocytes. Pretreatment with the androgen receptor (AR) inhibitor flutamide, but not the estrogen receptor inhibitor fulvestrant, abolished these effects. Knockdown of AR with siRNA also inhibited DHEA-induced decreases in BrdU uptake. These results suggest that DHEA-induced growth suppression of preadipocytes is mediated via AR. Therefore, both DHEA and testosterone similarly decrease adipocyte growth possibly via a common mechanism.

A novel liposome surface modification agent that prolongs blood circulation and retains surface ligand reactivity.

Liposomes are recognized as potentially useful drug carriers but many problems preclude practical medical application. Liposomes bind with serum proteins (opsonization) and are captured by the reticuloendothelial system cells in the liver and spleen, which limits their ability to deliver drugs to other target sites. Modification of lipids with flexible, hydrophilic polymers such as poly(ethylene glycol) (PEG) to yield sterically stabilized liposomes is one approach to improve liposome blood circulation and tissue distribution properties. In this study, we examined liposomes prepared using lipids modified with a new branched oligoglycerol (BGL) moiety for steric stabilization. This novel BGL comprised 14 glycerol units (termed BGL014) connected with flexible ether linkages, resulting in a branched cascade-like structure that is highly expanded in aqueous solution. BGL014 was coupled to 1,2-distearoylphosphatidylethanolamine to yield BGL014-modified lipids. Incorporation of BGL014 into liposomes (BGL014L) resulted in long blood circulation times, despite a much thinner fixed aqueous layer thickness compared to PEG formulations. BGL014 produced a liposome surface coating that appears to function through steric inhibition of non-specific protein binding without strong interference of specific protein-binding reactions. Liposome structure and functionality was maintained following BGL014-modification, as the incorporation ratio of drug remained high. These results suggest that the BGL014 modification of liposomes is a promising approach to produce stable and long circulating drug carriers capable of selective binding to specific proteins.

Impact of contrast-induced nephropathy and cardiovascular events by serum cystatin C in renal insufficiency patients undergoing cardiac catheterization.

We assessed the usefulness of serum cystatin C for predicting contrast-induced nephropathy (CIN) in patients (n = 100) undergoing coronary catheterization. After a 12-month follow-up, the incidence of CIN was 8.3% (n = 5) in patients with mild renal insufficiency (estimated glomerular filtration rate [eGFR] 60-89 mL/min per 1.73 m²), 34.4% (n = 10) in those with moderate renal insufficiency (eGFR 30-59 mL/min per 1.73 m²), and 100% (n = 3) in those with severe renal insufficiency (eGFR 15-29 mL/min per 1.73 m²). The sensitivity was 81.8% and specificity was 90.9% at the cutoff level of serum cystatin C >1.18 mg/L. Serum cystatin C levels were significantly (P < .001) higher in the patients with moderate renal insufficiency in the CIN group than those in the non-CIN group. Multivariate logistic regression analysis demonstrated that baseline serum cystatin C independently predicted short-term mortality (odds ratio [OR], 0.311; 95% confidence interval [CI] 0.058-0.538; P = .026). Baseline serum cystatin C significantly predicted the occurrence of CIN in the patients with moderate renal insufficiency.

Preparation and properties of branched oligoglycerol modifiers for stabilization of liposomes.

We examined the effect on drug delivery of liposomes with surfaces that were modified with branched oligoglycerols (BGLs) and explored possible formulation advantages to increase drug exposure. BGL012 is a branched oligoglycerol derivative with a cascade-like structure of 12 glycerol units, characterized as a widely spread structure in aqueous solution. We prepared BGL-phospholipid derivatives (BGL-PEs), including BGL012, by coupling 1,2-distearoylphosphatidylethanolamine to BGLs. BGL012-PE modification of the liposomes (BGL012L) achieved a long circulation time after intravenous injection in rats. The circulation lifetime of BGL012L was almost the same as that of polyethylene glycol (PEG)-modified liposomes. The surface of BGL012L induced the formation of a fixed aqueous layer and reduced protein adsorption on the liposome surface, without strong interference with the binding reaction on the liposome. Thus, the newly synthesized branched oligoglycerol derivatives are considered to have useful hydrophilic and physical properties for modifying the liposome surface to increase drug exposure.

Cystatin C: a better marker to detect coronary artery sclerosis.

BACKGROUND: Nowadays, early detection and treatment can often keep chronic kidney disease patients from getting worse and prevent the occurrence of cardiovascular disease. Cystatin C (Cys-C) is a new marker for renal dysfunction. This study investigated whether Cys-C played an important role for screening coronary artery disease. METHODS: The consecutive 88 outpatients (51 males and 37 females), who were suspected of having effort angina pectoris or asymptomatic ischemic heart disease, were enrolled. Serum Cys-C, which was obtained within 3 months before coronary angiography, was assessed with the presence or absence of coronary arteriosclerosis, the number of culprit arteries, and blood biochemical parameters. RESULTS: Mean serum Cys-C was 0.82+/-0.29 mg/l. Significant differences in the estimated creatinine clearance (p=0.036), hemoglobin A1c (p=0.01), left ventricular ejection fraction (p=0.01), creatinine (p=0.007), Cys-C (p=0.006), and high-density lipoprotein (HDL) cholesterol (p=0.001) were observed between the patients with or without coronary arteriosclerosis. Serum Cys-C was significantly greater in the multi-vessel disease (MVD) group than the 0 vessel disease (0VD) group (p<0.001). HDL cholesterol was significantly lower in the MVD group than the 0VD and single-vessel disease groups (p=0.002 and p=0.005, respectively). CONCLUSION: The results of this study suggest Cys-C might be one of the risk factors for coronary arteriosclerosis in the patients with suspected ischemic heart disease without any history of coronary artery disease. Cys-C was a useful marker to detect coronary artery disease and the level of Cys-C could reflect the severity of coronary arteriosclerosis.

A nanoparticle system specifically designed to deliver short interfering RNA inhibits tumor growth in vivo.

Use of short interfering RNA (siRNA) is a promising new approach thought to have a strong potential to lead to rapid development of gene-oriented therapies. Here, we describe a newly developed, systemically injectable siRNA vehicle, the "wrapsome" (WS), which contains siRNA and a cationic lipofection complex in a core that is fully enveloped by a neutral lipid bilayer and hydrophilic polymers. WS protected siRNA from enzymatic digestion, providing a long half-life in the systemic circulation. Moreover, siRNA/WS leaked from blood vessels within tumors into the tumor tissue, where it accumulated and was subsequently transfected into the tumor cells. Because the transcription factor KLF5 is known to play a role in tumor angiogenesis, we designed KLF5-siRNA to test the antitumor activity of siRNA/WS. KLF5-siRNA/WS exhibited significant antitumor activity, although neither WS containing control scrambled-siRNA nor saline containing KLF5-siRNA affected tumor growth. KLF5-siRNA/WS inhibited Klf5 expression within tumors at both mRNA and protein levels, significantly reducing angiogenesis, and we detected no significant acute or long-term toxicity. Our findings support the idea that siRNA/WS can be used to knock down specific genes within tumors and thereby exert therapeutic effects against cancers.