Exceptionally Stable Dimers and Trimers of Au25 Clusters Linked with a Bidentate Dithiol: Synthesis, Structure and Chirality Study.

A bidentate chiral dithiol (diBINAS) is utilised to bridge Au25 nanoclusters to form oligomers. Separation by size allows the isolation of fractions that are stable thanks to the bidentate nature of the linker. The structure of the products is elucidated by small-angle X-ray scattering and calculated using density functional theory. Additional structural details are studied by diffusion-ordered nuclear magnetic resonance spectroscopy, transmission electron microscopy and matrix-assisted laser desorption/ionization time of flight mass spectrometry. Significant changes in the optical properties are analysed by UV/Vis and fluorescence spectroscopies, with the latter demonstrating a strong emission enhancement. Furthermore, the emergent chiral characteristics are studied by circular dichroism. Due to the geometry constraints of the nanocluster assemblies, diBINAS can be regarded as a templating molecule, taking a step towards the directed self-assembly of metal clusters.

Differential expression profile between amygdala and blood during chronic lithium treatment in a rat model of depression - a pilot study.

Lithium is a mood stabilizer widely used in the pharmacotherapy of bipolar disorder and treatment­resistant depression. Taking into account dysregulated inflammatory activity in depression and the immunomodulatory role of lithium, we hypothesized that genes associated with inflammatory responses may be potential biomarkers of lithium action. We aimed to compare gene expression changes between the brain and the periphery after chronic lithium administration in an animal model of depression. Depressive behavior was induced by chronic mild stress protocol for 4 weeks. After 2 weeks, rats started to receive lithium (study group) or water (reference group). The control group were rats not exposed to stress. Amygdala, hippocampus, frontal cortex and peripheral blood were analyzed using whole transcriptome expression microarrays. Changes were confirmed with qPCR and ELISA assay. After 2 weeks of lithium administration, we observed significant changes in gene expression between amygdala and peripheral blood. Logistic regression analysis determined Alox15 expression as a predictor of lithium status, as its expression was tissue­specific and increased in amygdala and decreased in blood. Analysis of serum ALOX15 protein revealed its upregulation after two­week lithium administration. Our study suggests that lithium may have therapeutic potential in depressive behaviors. These results indicate immunomodulatory effect of lithium and that Alox15 may be a new potential marker of chronic lithium treatment.

Early synaptic deficits in GSK-3ß overexpressing mice.

Synaptic dysfunction is the prominent feature of many neuropsychiatric and neurological diseases, in which glycogen synthase kinase 3ß (GSK-3ß) has been shown to play a role. Overexpression of constitutively active form of GSK-3ß (GSK-3ß[S9A]) in mice recapitulates the cognitive and structural brain deficits characteristic for manic phase of bipolar disorder (BD). Yet, the mechanisms underlying GSK-3ß-induced synaptic dysfunction have not been fully elucidated. The aim of the present study was to dissect the effect of GSK-3ß overactivity on synaptic function in adolescent (3-week-old) mice. We found that overactivity of GSK-3ß in adolescent transgenic mice leads to an alteration in dendritic spines morphology of granule cells in dentate gyrus (DG) without changes in overall spine density. There was an increase in the number of thin, presumably immature dendritic spines in GSK-3ß[S9A] mice. Subsequent electrophysiological analysis showed changes in excitatory synaptic transmission manifested by an increase of inter-event intervals of miniature excitatory postsynaptic currents (mEPSCs) in DG granule cells and an increase in the number of silent (unfunctional) synapses at the perforant path-DG pathway in GSK-3ß[S9A] mice. Altogether, our data indicate that GSK-3ß overactivity leads to synaptic deficits in adolescent, GSK-3ß[S9A] mice. These data might provide potential mechanisms underlying GSK-3ß-induced synaptic dysfunction in psychiatric disorders.

Dysregulation of miRNAs Levels in Glycogen Synthase Kinase-3ß Overexpressing Mice and the Role of miR-221-5p in Synaptic Function.

Glycogen synthase kinase-3ß (GSK-3ß) is a highly expressed kinase in the brain, where it has an important role in synaptic plasticity. Aberrant activity of GSK-3ß leads to synaptic dysfunction which results in the development of several neuropsychiatric and neurological diseases. Notably, overexpression of constitutively active form of GSK-3ß (GSK-3ß[S9A]) in mice recapitulates the cognitive and structural defects characteristic for neurological and psychiatric disorders. However, the mechanisms by which GSK-3ß regulates synaptic functions are not clearly known. Here, we investigate the effects of GSK-3ß overactivity on neuronal miRNA expression in the mouse hippocampus. We found that GSK-3ß overactivity downregulates miRNA network with a potent effect on miR-221-5p (miR-221*). Next, characterization of miR-221* function in primary hippocampal cell culture transfected by miR-221* inhibitor, showed no structural changes in dendritic spine shape and density. Using electrophysiological methods, we found that downregulation of miR-221* increases excitatory synaptic transmission in hippocampal neurons, probably via postsynaptic mechanisms. Thus, our data reveal potential mechanism by which GSK-3ß and miRNAs might regulate synaptic function and therefore also synaptic plasticity.

Raman Spectroscopic Fingerprints of Atomically Precise Ligand Protected Noble Metal Clusters: Au38 (PET)24 and Au38-x Agx (PET)24.

Distinct Raman spectroscopic signatures of the metal core of atomically precise, ligand-protected noble metal nanoclusters are reported using Au38 (PET)24 and Au38-x Agx (PET)24 (PET = 2-phenylethanethiolate, -SC2 H4 C6 H5 ) as model systems. The fingerprint Raman features (occurring <200 cm-1 ) of these clusters arise due to the vibrations involving metal atoms of their Au23 or Au23-x Agx cores. A distinct core breathing vibrational mode of the Au23 core has been observed at 90 cm-1 . Whereas the breathing mode shifts to higher frequencies with increasing Ag content of the cluster, the vibrational signatures due to the outer metal-ligand staple motifs (between 200 and 500 cm-1 ) do not shift significantly. DFT calculations furthermore reveal weak Raman bands at higher frequencies compared to the breathing mode, which are associated mostly with the rattling of two central gold atoms of the bi-icosahedral Au23 core. These vibrations are also observed in the experimental spectrum. The study indicates that low-frequency Raman spectra are a characteristic fingerprint of atomically precise clusters, just as electronic absorption spectroscopy, in contrast to the spectrum associated with the ligand shell, which is observed at higher frequencies.

Molecular Regulation of the Melatonin Biosynthesis Pathway in Unipolar and Bipolar Depression.

Melatonin is a neurohormone that maintains the circadian rhythms of the body. By regulating the secretion of other hormones and neurotransmitters, it acts as a pleiotropic modulator that affects, for example, reproductive, immune, cardiovascular, sleep, and wake systems and mood. Thus, synthetic melatonin has become an essential component in the treatment of depressive disorders. Although we know the pathway of melatonin action in the brain, we lack comprehensive cross-sectional studies on the periphery of depressed patients. This study aimed to comprehensively analyze the differences between healthy control subjects (n = 84) and unipolar and bipolar depression patients (n = 94), including an analysis of the melatonin pathway at the level of the genes and serum biomarkers. An innovative approach is a pilot study based on gene expression profiling carried out on clinical and cell culture models using agomelatine and melatonin. We confirmed the melatonin biosynthesis pathway's molecular regulation dysfunctions, with a specific pattern for unipolar and bipolar depression, at the AANAT gene, its polymorphisms (rs8150 and rs3760138), and examined the serum biomarkers (serotonin, AANAT, ASMT, and melatonin). The biological pathway analysis uncovered pathways and genes that were uniquely altered after agomelatine treatment in a clinical model and melatonin treatment in a cell culture model. In both models, we confirmed the immunomodulatory effect of melatonin agents in depression.

Transcriptome Changes in Three Brain Regions during Chronic Lithium Administration in the Rat Models of Mania and Depression.

Lithium has been the most important mood stabilizer used for the treatment of bipolar disorder and prophylaxis of manic and depressive episodes. Despite long use in clinical practice, the exact molecular mechanisms of lithium are still not well identified. Previous experimental studies produced inconsistent results due to different duration of lithium treatment and using animals without manic-like or depressive-like symptoms. Therefore, we aimed to analyze the gene expression profile in three brain regions (amygdala, frontal cortex and hippocampus) in the rat model of mania and depression during chronic lithium administration (2 and 4 weeks). Behavioral changes were verified by the forced swim test, open field test and elevated maze test. After the experiment, nucleic acid was extracted from the frontal cortex, hippocampus and amygdala. Gene expression profile was done using SurePrint G3 Rat Gene Expression whole transcriptome microarrays. Data were analyzed using Gene Spring 14.9 software. We found that chronic lithium treatment significantly influenced gene expression profile in both mania and depression models. In manic rats, chronic lithium treatment significantly influenced the expression of the genes enriched in olfactory and taste transduction pathway and long non-coding RNAs in all three brain regions. We report here for the first time that genes regulating olfactory and taste receptor pathways and long non-coding RNAs may be targeted by chronic lithium treatment in the animal model of mania.

Genes involved in glucocorticoid receptor signalling affect susceptibility to mood disorders.

OBJECTIVES: In mood disorders chronic stress contributes to decreased glucocorticoid receptor signalling in the brain and resistance in the periphery. We hypothesised that aberrant glucocorticoid receptor function may result from genetic predisposition and that decreased GR signalling in the brain correlates with the expression of genes regulating GR complex formation. METHODS: We performed the association analysis of 698 patients: 490 patients with bipolar disorder and 208 patients with major depressive disorder and 564 control subjects. We genotyped 11 variants using TaqMan assays. Gene expression in the brain tissue was done in male Wistar rats after chronic mild stress protocol. The SRSF5 serum concentration was performed using ELISA. Data were analysed in Statistica and GraphPad. RESULTS: We found an association of STIP1 and SRSF5 variants with major depressive disorder and BAG1 variant with bipolar disorder. Gene expression analysis in a rat model of depression confirmed significant changes in the expression of SRSF5, BAG1, and FKBP4 in the brain. For SRSF5, we observed significantly increased expression in the serum of depressed females and male rats exposed to chronic stress. CONCLUSIONS: Our results indicate the involvement of genes associated with GR function, SRSF5, BAG1, and FKBP4 with susceptibility to mood disorders.

Clock genes polymorphisms in male bipolar patients with comorbid alcohol abuse.

BACKGROUND: Psychiatric comorbidity affects 24-65% patients with bipolar disorder (BD), 45% of which have alcohol abuse/dependence (AAD). Despite the fact that BD has an equal incidence in both genders, AAD more often occurs in men. We hypothesized that the presence of BD and AAD, reported as a secondary diagnosis, may result from a common genetic background. However, specific genetic factors predispose to gender differences. METHODS: Based on the relationship between circadian clock genes pathway and BD/AAD we decided to test the connection of four core clock genes with common genetic background of both diseases. We analyzed 436 patients with BD, among which 17% were diagnosed with AAD. The control group consisted of 417 healthy subjects. We analyzed 44 SNPs of the previously described core molecular clock genes: CLOCK, ARNTL, TIMELESS and PER3. RESULT: We found association of ARNTL gene (rs11600996) and PER3 gene (rs228642) polymorphisms with an increased risk of BD/AAD in a group of male patients. We also found that two other polymorphisms of PER3 gene, rs228682 and rs2640909, were associated with both AAD and family history of affective disorders. LIMITATIONS: Possible factors that could have influenced the results are: relatively small sample size, gender disproportion and unverifiable data form the patient interview. CONCLUSIONS: Our study confirms the existence of a link between clock genes and increased risk of alcohol abuse/dependence in male patients and the accumulation of risk genes in patients with a positive family history.

Dysregulation of miR-499, miR-708 and miR-1908 during a depression episode in bipolar disorders.

Affective disorders include unipolar disorder (UP) (depression episodes) and bipolar disorder (BP) (depression and mania episodes). Currently, no biological markers are known that can help to differentiate these disorders. However, recent studies have suggested that psychiatric disorders can be connected with small, non-coding RNA, like microRNA. The objective of this study was to analyse the expression level of three microRNAs (miR-499, miR-708, miR-1908) in bipolar and unipolar disorder during depression episodes and after entering the remission state. The group consisted of adult women only, 17 UP (age: 50±17) and 15 BP (age: 33±13) patients. The expression level of miRNAs was investigated by RT-qPCR with the TaqMan assay. Our study has shown a lower expression level of miR-499 (p=0.008), miR-708 (p=0.02) and miR-1908 (p=0.004) in depression episodes of the bipolar disorder patients in comparison to remission state. We have not found similar differences in unipolar disorder and between those types in acute phase of depression and during remission. Obtained results indicate that miRNAs: miR-499, miR-708 and miR-1908 are the most promising candidates for biomarkers of depression episodes of bipolar disorder.

Columnar self-assembly of N,N',N''-trihexylbenzene-1,3,5-tricarboxamides investigated by means of NMR spectroscopy and computational methods in solution and the solid state.

The columnar self-assembly resulting from units of N,N',N''-trihexylbenzene-1,3,5-tricarboxamide is investigated in solution and the solid state by means of NMR spectroscopy. A parallel computational study utilizing both semiempirical and DFT methods allows comparison between experimental results and calculated data for self-assembled and non-assembled structural hypotheses. The hybrid functional B3LYP is compared with the B3LYP-D and B97D functionals to assess contributions due to dispersion interactions. Interatomic distances are studied utilizing ROE experiments on proton spins in solution. Isotropic shifts as measured experimentally are shown to offer a method to assess the self-assemblies 'on-the-fly'. The anisotropic part of the shift interaction for carbon nuclei is probed in the solid state with specific magic-angle spinning experiments. The sensitivity of the NMR parameters for various carbon environments with respect to the orientation of the substituents and packing effects is investigated computationally. We show that all the utilized experimental techniques, in both solution and the solid state, and in combination with DFT calculations, are capable of discerning between assembled and non-assembled systems and offer a robust set of independent tools to highlight atomic details in self-organized structures.

Venlafaxine and sertraline does not affect the expression of genes regulating stress response in female MDD patients. / Wenlafaksyna i sertralina nie wplywaja na ekspresje genów regulujacych poziom kortyzolu u kobiet chorych na depresje.

OBJECTIVES: The aim of this study was to analyze the expression of 3 genes involved in the regulation of HPA axis: GR, HSP90 and FKBP5, in patients with major depressive disorder (MDD) before antidepressant treatment and after 8 weeks of pharmacotherapy. Additionally, we analyzed the level of glucocorticoid receptor isoforms before and after treatment. METHODS: The study included 30 female patients (aged 18-60 years), with major depres- sive disorder diagnosed on the basis of the Structured Clinical Interview for DSM-IV (SCID). Antidepressant treatment included use of sertraline or venlafaxine. The assessment of patients' mental state (severity of depression) was checked by the Hamilton Depression Rating Scale (HDRS). After 8 weeks of treatment, the same clinical and molecular tests were performed. All of the patients underwent dexamethasone suppression test (DST). MRNA was isolated from the peripheral blood to evaluate the expression of the studied genes using real-time PCR with TaqMan probes. The concentration of GR isoforms (α and ß) in serum was also determined using ELISA. Statistical analysis was performed using Statistica v.12.0 software. RESULTS: The abnormal cortisol level was only seen in 20% of patients. Dysregulation on HPA axis was observed in 10% of patients. We observed significant clinical improvement after 8 weeks of pharmacotherapy in all patients. Almost the whole group of patients (except one patient) showed full remission of symptoms. We observed significant moderate correlation between cortisol level after DST before treatment and after 8 weeks of pharmacotherapy (r2 = 0.44). The results showed no significant difference in the expression of 3 analyzed genes compared before and after 8 weeks of therapy. The results of ELISA showed decreased level of α isoform after pharmacotherapy, independent of drug. CONCLUSIONS: The results showed no significant changes in the expression of genes involved in the stress axis activity during antidepressant therapy.

A multifaceted approach to hydrogen storage.

The widespread adoption of hydrogen as an energy carrier could bring significant benefits, but only if a number of currently intractable problems can be overcome. Not the least of these is the problem of storage, particularly when aimed at use onboard light-vehicles. The aim of this overview is to look in depth at a number of areas linked by the recently concluded HYDROGEN research network, representing an intentionally multi-faceted selection with the goal of advancing the field on a number of fronts simultaneously. For the general reader we provide a concise outline of the main approaches to storing hydrogen before moving on to detailed reviews of recent research in the solid chemical storage of hydrogen, and so provide an entry point for the interested reader on these diverse topics. The subjects covered include: the mechanisms of Ti catalysis in alanates; the kinetics of the borohydrides and the resulting limitations; novel transition metal catalysts for use with complex hydrides; less common borohydrides; protic-hydridic stores; metal ammines and novel approaches to nano-confined metal hydrides.

Matrix metalloproteinases in type 2 diabetes and non-diabetic controls: effects of short-term and chronic hyperglycaemia.

INTRODUCTION: The role of matrix metalloproteinases (MMPs) in type 2 diabetes mellitus (DM) is not clear as increased activation of MMPs in the vasculature contrasts with decreased activity of MMPs in the kidneys, contributing to development of nephropathy. MATERIAL AND METHODS: We measured serum MMP-2 and MMP-9 in 22 subjects with type 2 DM age (mean ± SD) 56.7 ±16.8 years, BMI 31.8 ±4.6 kg/m(2), HbA(1c) 8.45 ±1.78% and in 32 controls, age 39.2 ±16.0 years, BMI 35.2 ±8.5 kg/m(2). In 15 subjects with 2 DM we also measured MMP-2 and MMP-9 at discharge from hospital and after 3 months (n = 8). In controls, MMP-2 and -9 were also measured during 75 g oral glucose tolerance test (OGTT). RESULTS: Concentrations of MMP-2 and MMP-9 were lower in subjects with type 2 DM (219 ±62 ng/ml vs. 305 ±63 ng/ml and 716 ±469 ng/ml vs. 1285 ±470 ng/ml, for MMP-2 and MMP-9, respectively, p < 0.05). MMP-9 concentrations fell at 120 min of OGTT from 1675 ±372 ng/ml to 1276 ±422 ng/ml (p < 0.05). In diabetic subjects there was a correlation between MMP-9 and HbA(1c) (r = 0.51, p< 0.05). In subjects with diabetes there was a fall of HbA(1c) from 9.77 ±1.76% to 8.36 ±1.54% (p < 0.01), at three months post-discharge. There was no difference in MMP-2, but there was a fall in MMP-9 at three months post-discharge in comparison to concentrations observed at admission (854 ±560 ng/ml vs. 500 ±235 ng/ml, p= 0.02). CONCLUSIONS: Matrix metalloproteinases in type 2 and MMP-9 concentrations were lower in subjects with 2 DM than in non-diabetic controls. Regulation of MMPs appears to be complex as hyperglycaemia during OGTT results in a decrease in MMP-9, while chronic hyperglycaemia, reflected by HbA(1c), correlates with MMP-9 concentrations in subjects with 2 DM.