Repetitive transcranial magnetic stimulation for protection against delayed neuronal death induced by transient ischemia

OBJECT: Data in the present study demonstrate that repetitive transcranial magnetic stimulation (rTMS) induces ischemic tolerance against delayed neuronal death (DND) of hippocampal neurons following an otherwise lethal ischemic insult. METHODS: Various regimens of rTMS were delivered to adult gerbils at various times prior to an episode of ischemia induced by transient (5-minute) bilateral common carotid artery (CCA) occlusion. The extent of DND in the CA1 region of the hippocampus was assessed quantitatively 7 days after the transient ischemic episode. When rTMS was delivered 2 to 5 days prior to bilateral CCA occlusion, DND was substantially attenuated; delivery of rTMS 12 to 24 hours prior to occlusion induced partial tolerance. In the group of animals that had received stimulation 2 days prior to occlusion, neuron density in the CA1 sector was significantly higher (three gerbils, 210.33, 86.01% of normal) than in the group that experienced ischemia only (three gerbils, 10.66, 4.36% of normal). A similar degree of neuron sparing occurred when stimulation was delivered 3, 4, or 5 days prior to occlusion. Note that rTMS was effective when it was delivered at frequencies of 25 and 50 Hz. Stimulation at 25 Hz for 128 seconds (3200 pulses) was more effective than stimulation at 50 Hz for 64 seconds (3200 pulses) or 128 seconds (6400 pulses), however. CONCLUSIONS: Noninvasive rTMS represents an important tool for exploring the mechanisms of ischemic tolerance and preventing ischemic neuronal damage.     

Application of a Machine Learning Algorithm for Structural Brain Images in Chronic Schizophrenia to Earlier Clinical Stages of Psychosis and Autism Spectrum Disorder: A Multiprotocol Imaging Dataset Study

Background and HypothesisMachine learning approaches using structural magnetic resonance imaging (MRI) can be informative for disease classification; however, their applicability to earlier clinical stages of psychosis and other disease spectra is unknown. We evaluated whether a model differentiating patients with chronic schizophrenia (ChSZ) from healthy controls (HCs) could be applied to earlier clinical stages such as first-episode psychosis (FEP), ultra-high risk for psychosis (UHR), and autism spectrum disorders (ASDs).Study DesignTotal 359 T1-weighted MRI scans, including 154 individuals with schizophrenia spectrum (UHR, n = 37; FEP, n = 24; and ChSZ, n = 93), 64 with ASD, and 141 HCs, were obtained using three acquisition protocols. Of these, data regarding ChSZ (n = 75) and HC (n = 101) from two protocols were used to build a classifier (training dataset). The remainder was used to evaluate the classifier (test, independent confirmatory, and independent group datasets). Scanner and protocol effects were diminished using ComBat.Study ResultsThe accuracy of the classifier for the test and independent confirmatory datasets were 75% and 76%, respectively. The bilateral pallidum and inferior frontal gyrus pars triangularis strongly contributed to classifying ChSZ. Schizophrenia spectrum individuals were more likely to be classified as ChSZ compared to ASD (classification rate to ChSZ: UHR, 41%; FEP, 54%; ChSZ, 70%; ASD, 19%; HC, 21%).ConclusionWe built a classifier from multiple protocol structural brain images applicable to independent samples from different clinical stages and spectra. The predictive information of the classifier could be useful for applying neuroimaging techniques to clinical differential diagnosis and predicting disease onset earlier.     

Effect of the XIAP inhibitor Embelin on TRAIL-induced apoptosis of pancreatic cancer cells

BACKGROUND: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potent inducer of apoptosis in a wide variety of tumor cells, while it has no toxicity for the majority of normal cells.Therefore, TRAIL may be a suitable agent for anticancer therapy. We previously reported that a number of pancreatic cancer cell lines show resistance to TRAIL-induced apoptosis via overexpression of XIAP and FLIP. The present study was conducted to further examine TRAIL-based therapeutic strategies by aiming to restore functional apoptotic pathways in resistant pancreatic cancer cells. METHODS: In various pancreatic cancer cell lines, TRAIL-induced apoptosis was evaluated in the presence or absence of an XIAP-inhibitor (Smac peptide). Second, TRAIL-induced apoptosis was evaluated in TRAIL-resistant AsPC-1 cells with or without FLIP antisense. Third, the combined effect of Smac peptide and FLIP antisense was tested, and the activation of apoptosis-related caspases and poly (ADP-ribose) polymerase was evaluated. Finally, TRAIL-induced apoptosis was evaluated in the presence or absence of FLIP antisense and an XIAP inhibitor (embelin). RESULTS: Smac peptide enhanced TRAIL-induced apoptosis in a dose-dependent manner for several pancreatic cancer cell lines, but showed no effect on TRAIL-resistant AsPC-1 cells. Smac peptide alone had no influence on cell viability. TRAIL-induced apoptosis was restored in TRAIL-resistant AsPC-1 cells by exposure to FLIP antisense, which suppressed the expression of FLIP. The effect of TRAIL was augmented by the combination of FLIP antisense and Smac peptide. Similarly, TRAIL-induced apoptosis was restored by the combination of FLIP antisense and embelin. Activation of apoptotic caspases and cleavage of poly (ADP-ribose) polymerase was observed after sensitization of TRAIL-resistant pancreatic cancer cells. CONCLUSIONS: Pancreatic cancer cells gain resistance to TRAIL-induced apoptosis via expression of the antiapoptotic proteins XIAP and FLIP. Smac peptide and FLIP antisense could restore the apoptotic effect of TRAIL. An XIAP inhibitor, embelin, enhanced the effect of TRAIL in the presence of FLIP antisense. These findings may provide useful information for the development of TRAIL-based therapeutic strategies by restoring functional apoptotic pathways in resistant pancreatic cancer cells. In addition, a low molecular weight XIAP inhibitor like embelin could be a lead compound for the development of effective XIAP inhibitors.     

Polyarthritis Caused by Methimazole in Two Japanese Patients with Graves’ Disease

In many countries, methimazole (MMI) therapy is the first-line treatment in children with Graves’ disease (GD). The rate of side effects of antithyroid drugs (ATDs) in children has been reported to range between 6% and 35%. Of these side effects, polyarthritis is uncommon but serious, and can also develop as a part of the antineutrophil cytoplasmic antibody-associated vasculitis that is induced by ATDs. Here, we describe two GD girl patients aged 15 years and 11 years who developed polyarthritis. The onset of polyarthritis in these patients was 24 days and 28 days after the initiation of MMI therapy, respectively. MMI was suspected of causing the polyarthritis in the two patients and was withdrawn. The symptoms of polyarthritis disappeared rapidly following cessation of treatment. Subsequently, one patient was treated with 131I therapy and the other patient was subjected to thyroidectomy. Although it rarely occurs in pediatric GD patients, severe polyarthritis is a serious side effect of MMI and is an indication for prompt cessation of treatment. Conflict of interest:None declared.     

Validation of a reference control for an SYBR-Green fluorescence assay-based real-time PCR for detection of bovine herpesvirus 5 in experimentally exposed bovine embryos

The objective of this study was to optimize an internal control to improve SYBR-Green-based qPCR to amplify/detect the BoHV-5 US9 gene in bovine embryos produced in vitro and experimentally exposed to the virus. We designed an SYBR-Green-based binding assay that is quick to perform, reliable, easily optimized and compares well with the published assay. Herein we demonstrated its general applicability to detect BoHV-5 US9 gene in bovine embryos produced in vitro experimentally exposed to BoHV-5. In order to validate the assay, three different reference genes were tested; and the histone 2a gene was shown to be the most adequate for normalizing the qPCR reaction, by considering melting and standard curves (p < 0.05). On the other hand, no differences were found in the development of bovine embryos in vitro whether they were exposed to BoHV-5 reference and field strains comparing to unexposed embryos. The developed qPCR assay may have important field applications as it provides an accurate BoHV-5 US9 gene detection using a proven reference gene and is considerably less expensive than the TaqMan qPCR currently employed in sanitary programs.     

Activation of proprotein convertase in the mouse habenula causes depressive-like behaviors through remodeling of extracellular matrix

The lateral habenula (LHb) attracts a growing interest as a regulator of monoaminergic activity which were frequently reported to be defective in depression. Here we found that chronic social defeat stress (CSDS) increased production of pro-inflammatory cytokines in LHb associated with mobilization of monocytes and remodeling of extracellular matrix by increased matrix metalloproteinase (MMP) activity. RNA-seq analysis identified proprotein convertase Pcsk5 as an upstream regulator of MMP activation, with upregulation in LHb neurons of mice with susceptibility to CSDS. PCSK5 facilitated motility of microglia in vitro by converting inactive pro-MMP14 and pro-MMP2 to their active forms, highlighting its role in mobilization of microglia and monocytes in neuroinflammation. Suppression of Pcsk5 expression via small interfering RNA (siRNA) ameliorated depressive-like behaviors and pathological mobilization of monocytes in mice with susceptibility to CSDS. PCSK5-MMPs signaling pathway could be a target for development of the antidepressants targeting the inflammatory response in specific brain regions implicated in depression.Subject terms: Cellular neuroscience, Gene expression analysis     

Increased bone resorption may play a crucial role in the occurrence of osteopenia in patients with type 2 diabetes: Possible involvement of accelerated polyol pathway in its pathogenesis

In order to investigate the underlying mechanism of alterations in bone mineral metabolism in patients with type 2 diabetes, we determined circulating levels of bone functional markers along with urinary excretion of sorbitol (SOR) and bone mineral density (BMD), and also examined their mutual interrelationship. A total of 151 male type 2 diabetic patients were examined in this study. Forty-eight age-matched male healthy subjects were also studied as the controls. A significant reduction of serum intact osteocalcin (i-OC) was found in the diabetic groups (p<0.01). On the other hand, circulating levels of tartrate resistant acid phosphatase (TRAP) in the diabetic patients were significantly higher than those in the controls (p<0.01). Interestingly, a significantly negative relationship was observed between BMD and serum TRAP (p<0.01), although no significant relationship was noted between BMD and serum i-OC in diabetic patients. Urinary excretion of SOR was significantly elevated in the diabetic patients when compared with the controls (p<0.01). In addition, a significantly positive correlation was observed between serum TRAP and urinary SOR (p<0.01), but not between serum i-OC and urinary SOR. Elevated serum TRAP in diabetes was reduced after the administration of aldose reductase inhibitor (p<0.05). It seems most likely that the increase in osteoclastic function probably due to accelerated polyol pathway plays a crucial role in the pathogenesis of decreased bone mineral content in male patients with type 2 diabetes.     

Altered relationship between body fat and plasma adiponectin in end-stage renal disease

Patients with end-stage renal disease (ESRD) show an inverse association between body mass index and risk of death from cardiovascular disease. Paradoxical epidemiology may suggest some beneficial effects of body fat in ESRD. Because an antiatherogenic adipocytokine adiponectin is increased in uremic plasma, we tested a hypothesis that, in ESRD, plasma adipocytokine profile may be less atherogenic or that the relationship between body fat and adipocytokines may be altered. The subjects were 103 patients with ESRD undergoing hemodialysis and 166 healthy subjects comparable in age and sex. We measured body fat mass by dual-energy x-ray absorptiometry and plasma levels of adiponectin and leptin by enzyme-linked immunosorbent assay. The ESRD group showed a significant increase in plasma adiponectin, leptin, and adiponectin/leptin ratio than the healthy subjects. Although sex and fat mass were significant factors correlating with plasma adiponectin level in the healthy group, none of these were significantly associated with plasma adiponectin in the patients with ESRD. In contrast, leptin showed significant relationships with sex and fat mass regardless of the presence of ESRD. Plasma adiponectin correlated negatively with plasma triglycerides and positively with high-density lipoprotein cholesterol in both healthy and ESRD groups, suggesting that uremic adiponectin retains its actions in favor of its antiatherogenicity. Thus, plasma adipocytokine profile was altered in ESRD, and the effects of body fat and sex on adiponectin were less significant in the patients with ESRD.