Sex-specific contribution of glucocorticoid receptor alpha isoforms to anxiety and depressive-like behavior in mice.

Adolescent stress predisposes individuals to increased risk for anxiety and depression in adulthood. The stress response is mediated by the glucocorticoid receptor (GR) via regulation of GR-responsive genes involved in brain reaction to stress. Although dysregulation of GR in depression is well documented, this is the first study investigating the role of GRα isoforms in pathogenesis of depression. We exposed adolescent male and female C57BL/6J mice to chronic unpredictable stress (CUS) for 12 days starting at postnatal day 28 (PND28). Tests evaluating anxiety and depressive-like behaviors were performed at PND70. We analyzed corticosterone concentrations in serum, levels of GRα isoforms (95, 67, 50, 40, and 25 kDa), and mRNA levels of GR-responsive genes (GR, FKBP5, BDNF, and IL-1ß) in the hippocampus and the prefrontal cortex (PFC). CUS increased anxiety and depressive-like behavior in adult animals of both sexes, but did not affect corticosterone serum levels, 95 and 67 kDa GR isoforms. However, the levels of shorter GRα isoforms (50, 40, and 25 kDa) were altered in adult mice underwent CUS, in sex- and brain structure-specific way. Changes in gene expression revealed that female depressive-like behavior could be related to increased levels of IL-1ß in hippocampus and reduced BDNF levels in both hippocampus and PFC. However, in males, adolescent CUS increased expression of GR in adult hippocampus and BDNF in PFC. These findings suggest that adolescent stress altered levels of GRα isoforms, especially those with lower molecular weight, in sex- and tissue-specific ways, contributing to anxiety and depression in adult mice.

Predictors of health related-quality of life among elderly with disabilities.

AIM: There have been no previous studies of health-related quality of life (HRQOL) among adults aged 65 years and older with disabilities in Serbia. The aim of study was to identify predictors of HRQOL in the context of sociodemographic characteristics, disability aetiology, comorbid diseases, indices of comorbidities, realization of social rights, and domestic violence. METHODS: The cross-sectional study involved 275 consecutive elderly outpatients with disabilities. They were recruited by general practitioners at Primary Health Centers in Belgrade, Serbia, from March to May 2015. Data were acquired through face-to-face interviews and general practitioners' charts, while the generic 36-item Short Form Health Survey was used to assess HRQOL. In statistical analysis, Student's t-test, Z-test, Spearman's correlation test, and both univariate and multivariate linear regression were performed. RESULTS: Multivariate analysis revealed that a higher Functional Comorbidity Index (ß = -0.194, P < 0.01) and not asking for realization of right to assistance and care financial benefits (ß = -0.142, P < 0.05) were predictors of a lower scores Mental Composite Score (F = 9.262; P < 0.001). Not asking for realization of right to assistance and care financial benefits (ß = -0.187, P < 0.01), congestive heart failure (ß = -0.123, P < 0.05), and stroke (ß = -0.120, P < 0.05) were predictors of a lower Physical Composite Score (F = 7.169, P < 0.001). CONCLUSIONS: This study provides valuable data for better understanding the underlying factors associated with the HRQOL of elderly persons with disabilities, and currently, these are the only available data of their kind in Serbia. National authorities could identify predictors of HRQOL as a basic starting point for improving the social welfare and health-care systems. Better prevention and management of clinical factors, increased access to social services, and enhanced delivery of social services will improve the ageing process and HRQOL of this vulnerable population.

Dysbiosis of microbiome and probiotic treatment in a genetic model of autism spectrum disorders.

Recent studies have determined that the microbiome has direct effects on behavior, and may be dysregulated in neurodevelopmental conditions. Considering that neurodevelopmental conditions, such as autism, have a strong genetic etiology, it is necessary to understand if genes associated with neurodevelopmental disorders, such as Shank3, can influence the gut microbiome, and if probiotics can be a therapeutic tool. In this study, we have identified dysregulation of several genera and species of bacteria in the gut and colon of both male and female Shank3 KO mice. L. reuteri, a species with decreased relative abundance in the Shank3 KO mice, positively correlated with the expression of gamma-Aminobutyric acid (GABA) receptor subunits in the brain. Treatment of Shank3 KO mice with L. reuteri induced an attenuation of unsocial behavior specifically in male Shank3 mice, and a decrease in repetitive behaviors in both male and female Shank3 KO mice. In addition, L. reuteri treatment affected GABA receptor gene expression and protein levels in multiple brain regions. This study identifies bacterial species that are sensitive to an autism-related mutation, and further suggests a therapeutic potential for probiotic treatment.

Lymphocyte levels of redox-sensitive transcription factors and antioxidative enzymes as indicators of pro-oxidative state in depressive patients.

BACKGROUND: Oxidative stress is reliably observed in major depressive disorder (MDD). However, molecular data on the principal cellular redox-sensitive transcriptional factors and the levels of their downstream-regulated antioxidant enzymes in MDD are scarce. METHODS: In the peripheral blood mononuclear cells (PBMC) of subjects with a current episode of MDD (n = 30) and healthy controls (n = 35), we investigated alterations in the levels of redox-sensing nuclear factor (erythroid-derived 2)-like 2 (Nrf2) protein, its inhibitor Keap1, and nuclear factor-κB (NF-κB), along with their cognate downstream effectors, the antioxidant enzymes (AOEs): manganese and copper zinc superoxide dismutase (MnSOD and CuZnSOD, respectively), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GLR). RESULTS: MDD subjects exhibited higher levels of Nrf2 and its regulator Keap1, as well as NF-κB in the cytoplasm of PBMC compared to controls. This state was further reflected by increased levels of MnSOD, CuZnSOD and CAT proteins and by the lack of correlation between MnSOD and CAT, which could indicate impaired oxidative detoxification capacity in MDD patients. Moreover, increased levels of MnSOD, CuZnSOD and CAT in MDD patients positively correlated with levels of Nrf2, while increased levels of SODs were also positively related to NF-κB. There were no differences regarding the levels of GPx and GLR proteins, but the ratio of GLR/GPx was reduced, suggesting diminished capacity of GPx in antioxidative defence in PBMC of MDD subjects. CONCLUSION: These data provide evidence that MDD is characterized by up-regulation of redox-sensitive transcriptional factors (Nrf2 and NF-κB) and AOEs (MnSOD, CuZnSOD and CAT), indicating pro-oxidative state in the PBMC of MDD patients.

Ketamine's Amelioration of Fear Extinction in Adolescent Male Mice Is Associated with the Activation of the Hippocampal Akt-mTOR-GluA1 Pathway.

Fear-related disorders, including post-traumatic stress disorder (PTSD), and anxiety disorders are pervasive psychiatric conditions marked by persistent fear, stemming from its dysregulated acquisition and extinction. The primary treatment for these disorders, exposure therapy (ET), relies heavily on fear extinction (FE) principles. Adolescence, a vulnerable period for developing psychiatric disorders, is characterized by neurobiological changes in the fear circuitry, leading to impaired FE and increased susceptibility to relapse following ET. Ketamine, known for relieving anxiety and reducing PTSD symptoms, influences fear-related learning processes and synaptic plasticity across the fear circuitry. Our study aimed to investigate the effects of ketamine (10 mg/kg) on FE in adolescent male C57 BL/6 mice at the behavioral and molecular levels. We analyzed the protein and gene expression of synaptic plasticity markers in the hippocampus (HPC) and prefrontal cortex (PFC) and sought to identify neural correlates associated with ketamine's effects on adolescent extinction learning. Ketamine ameliorated FE in the adolescent males, likely affecting the consolidation and/or recall of extinction memory. Ketamine also increased the Akt and mTOR activity and the GluA1 and GluN2A levels in the HPC and upregulated BDNF exon IV mRNA expression in the HPC and PFC of the fear-extinguished mice. Furthermore, ketamine increased the c-Fos expression in specific brain regions, including the ventral HPC (vHPC) and the left infralimbic ventromedial PFC (IL vmPFC). Providing a comprehensive exploration of ketamine's mechanisms in adolescent FE, our study suggests that ketamine's effects on FE in adolescent males are associated with the activation of hippocampal Akt-mTOR-GluA1 signaling, with the vHPC and the left IL vmPFC as the proposed neural correlates.

Contribution of the opioid system to depression and to the therapeutic effects of classical antidepressants and ketamine.

Major depressive disorder (MDD) afflicts approximately 5 % of the world population, and about 30-50 % of patients who receive classical antidepressant medications do not achieve complete remission (treatment resistant depressive patients). Emerging evidence suggests that targeting opioid receptors mu (MOP), kappa (KOP), delta (DOP), and the nociceptin/orphanin FQ receptor (NOP) may yield effective therapeutics for stress-related psychiatric disorders. As depression and pain exhibit significant overlap in their clinical manifestations and molecular mechanisms involved, it is not a surprise that opioids, historically used to alleviate pain, emerged as promising and effective therapeutic options in the treatment of depression. The opioid signaling is dysregulated in depression and numerous preclinical studies and clinical trials strongly suggest that opioid modulation can serve as either an adjuvant or even an alternative to classical monoaminergic antidepressants. Importantly, some classical antidepressants require the opioid receptor modulation to exert their antidepressant effects. Finally, ketamine, a well-known anesthetic whose extremely efficient antidepressant effects were recently discovered, was shown to mediate its antidepressant effects via the endogenous opioid system. Thus, although opioid system modulation is a promising therapeutical venue in the treatment of depression further research is warranted to fully understand the benefits and weaknesses of such approach.

SARS-CoV-2 and Plasmodium falciparum coinfection: a case report.

BACKGROUND: A rare case of coinfection of Plasmodium falciparum and SARS-CoV-2 disease in Croatia is presented in this report. METHODS: We tracked epidemiological and laboratory findings in a patient with SARS-CoV-2 and Plasmodium falciparum coinfection. A complete blood count was performed using the Sysmex XN-2000 analyser (Sysmex Corporation, Kobe, Japan), coagulation analyses were performed using the BCS XP coagulometer (Siemens Healthineers AG, Erlangen, Germany). Procalcitonin (PCT) and Interleukin-6 (IL-6) were measured by electrochemiluminescence immunoassay (ECLIA) using the Cobas e411 (Roche Diagnostics GmbH, Mannheim, Germany) analyser and high sensitivity troponin I (hsTnI) was measured using the Dimension EXL with LM analyser (Siemens Healthcare Diagnostics, Newark, USA). All other biochemistry analyses were performed using the Olympus AU680 (Beckman Coulter, Brea, California, USA) analyser. White blood cell differential analysis has been performed by examining the blood smear using the CellaVision DM1200 (CellaVision AB, Lund, Sweden) automatic analyser. RESULTS: Even though the patient's initial health condition was disturbed, as a result of the physician's comprehensive anamnesis accompanied by laboratory findings, prompt diagnosis and appropriate therapy were assured, and consequently, the patient recovered. CONCLUSION: In a pandemic, testing each febrile patient for the SARS-CoV-2 virus is of essential importance. However, the possibility of coinfection with another infectious disease agent cannot be disregarded.

Effectiveness of Epidural Steroid Injection Depending on Discoradicular Contact: A Prospective Randomized Trial.

Lumbar radicular pain is a major public health and economic problem. It is among the most common reasons for professional disability. The most common cause of lumbar radicular pain is intervertebral disc herniation, which results from degenerative disc changes. The dominant pain mechanisms are direct pressure of the hernia on the nerve root and the local inflammatory process triggered by intervertebral disc herniation. Treatment of lumbar radicular pain includes conservative, minimally invasive, and surgical treatment. The number of minimally invasive procedures is constantly increasing, and among these methods is epidural administration of steroids and local anesthetic through a transforaminal approach (ESI TF). The aim of this research was to examine the effectiveness of ESI TF as measured by a visual analog scale (VAS) and the Oswestry Disability Index (ODI), depending on whether there is contact between the herniated intervertebral disc and the nerve root. In both groups of participants, there was a significant reduction in pain intensity, but there was no significant difference between the groups. In the group with disc herniation and nerve root contact, the only significant reduction was in pain intensity (p < 0.001). There were no significant differences in measurements in other domains of the ODI. In the group without disc herniation and nerve contact, there was a significant difference in all domains except weight lifting. In the group without contact, there was significant improvement after 1 month (p = 0.001) and 3 months (p < 0.001) according to the ODI, while there was no significant improvement in the group with contact. In addition, there were no significant differences in the distribution of participants based on the ODI and whether disc herniation and nerve contact was present. The results suggest that transforaminal epidural administration of steroids is a clinically effective method for treating lumbar radicular pain caused by intervertebral disc herniation in people with and without nerve root contact, without significant differences.

Tryptophan metabolites in depression: Modulation by gut microbiota.

Clinical depression is a multifactorial disorder and one of the leading causes of disability worldwide. The alterations in tryptophan metabolism such as changes in the levels of serotonin, kynurenine, and kynurenine acid have been implicated in the etiology of depression for more than 50 years. In recent years, accumulated evidence has revealed that gut microbial communities, besides being essential players in various aspects of host physiology and brain functioning are also implicated in the etiology of depression, particularly through modulation of tryptophan metabolism. Therefore, the aim of this review is to summarize the evidence of the role of gut bacteria in disturbed tryptophan metabolism in depression. We summed up the effects of microbiota on serotonin, kynurenine, and indole pathway of tryptophan conversion relevant for understanding the pathogenesis of depressive behavior. Moreover, we reviewed data regarding the therapeutic effects of probiotics, particularly through the regulation of tryptophan metabolites. Taken together, these findings can open new possibilities for further improvement of treatments for depression based on the microbiota-mediated modulation of the tryptophan pathway.

GluN2A-ERK-mTOR pathway confers a vulnerability to LPS-induced depressive-like behaviour.

Inflammation plays a key role in the pathogenesis of the major depressive disorder. Namely, neuroinflammation can induce the production of neuroactive metabolites that interfere with N-methyl-D-aspartate receptors (NMDAR)-mediated glutamatergic neurotransmission and contribute to depressive-like behaviour. On the other hand, mammalian target of rapamycin (mTOR) activity with synaptogenic effects is the main mediator of antidepressant effects of several potent NMDAR antagonists. In this study, we investigated the specific role of GluN2A subunits of NMDAR on the activity of mTOR signaling and behaviour in lipopolysaccharide (LPS)-induces model of depression. The results showed that mice lacking GluN2A subunit did not display depressive-like behavior after the immune challenge, opposite to LPS-treated wild-type mice. Specifically, in GluN2A knockout mice, we estimated the activity of the mTOR pathway in the hippocampus and prefrontal cortex (PFC) by measuring synaptic levels of upstream regulators (p-Akt, p-ERK, and p-GSK3ß) and downstream effectors (p-mTOR, and p-p70S6K) of mTOR activity. In addition, we assessed the changes in the levels of two important synaptic markers, GluA1 and PSD-95. Contrary to downregulated mTOR signaling and decreased synaptic markers in LPS-treated wild-type animals, the resilience of GluN2A KO mice to depressive-like behaviour was paralleled with sustained mTOR signaling activity synaptic stability in hippocampus and PFC. Finally, we disclosed that resistance of GluN2A knockouts to LPS-induced depressive-like behavior was ERK-dependent. These findings demonstrate that GluN2A-ERK-mTOR signaling is a vulnerability factor of inflammation-related depressive behaviour, making this signaling pathway the promising target for developing novel antidepressants.

Laboratory policies and practices for thyroid function tests in Croatia: survey on behalf of Working Group for Laboratory Endocrinology of the Croatian Society of Medical Biochemistry and Laboratory Medicine.

Introduction: Laboratory plays important part in screening, diagnosis, and management of thyroid disorders. The aim of this study was to estimate current laboratory preanalytical, analytical and postanalytical practices and policies in Croatia. Materials and methods: Working Group for Laboratory Endocrinology of the Croatian Society of Medical Biochemistry and Laboratory Medicine designed a questionnaire with 27 questions and statements regarding practices and protocols in measuring thyroid function tests. The survey was sent to 111 medical biochemistry laboratories participating in external quality assurance scheme for thyroid hormones organized by Croatian Centre for Quality Assessment in Laboratory Medicine. Data is presented as absolute numbers and proportions. Results: Fifty-three participants returned the questionnaire. Response rate varied depending on question, yielding a total survey response rate of 46-48%. All respondents perform thyroid stimulating hormone (TSH). From all other thyroid tests, most performed is free thyroxine (37/53) and least TSH-stimulating immunoglobulin (1/53). Laboratories are using nine different immunoassay methods. One tenth of laboratories is verifying manufacturer's declared limit of quantification for TSH and one third is verifying implemented reference intervals for all performed tests. Most of laboratories (91%) adopt the manufacturer's reference interval for adult population. Reference intervals for TSH are reported with different percentiles (90, 95 or 99 percentiles). Conclusion: This survey showed current practices and policies in Croatian laboratories regarding thyroid testing. The results identified some critical spots and will serve as a foundation in creating national guidelines in order to harmonize laboratory procedures in thyroid testing in Croatia.

The FKBP5 genotype and childhood trauma effects on FKBP5 DNA methylation in patients with psychosis, their unaffected siblings, and healthy controls.

Hypothalamic-pituitary-adrenal (HPA) axis activity mediates the relationship between childhood trauma (CT) and psychosis. The FKBP5 gene, one of the key regulators of HPA axis activity after stress exposure, has been found associated with psychosis. Allele-specific and CT related FKBP5 demethylation in intron 7 was revealed in different psychiatric disorders. However, no studies have investigated FKBP5 methylation in subjects with different genetic liability for psychosis. A total of 144 participants were included in the study: 48 patients with psychotic disorders, 50 unaffected siblings, and 46 healthy controls. CT was assessed by Childhood Trauma Questionnaire. The FKBP5 rs1360780 was genotyped and FKBP5 methylation analyses were performed using bisulfite conversion followed by Sanger sequencing at three CpG sites in intron 7. Mixed linear model was used to assess group differences depending on rs1360780 T allele and CT. Results showed a significant T allele-dependent decrease of FKBP5 methylation in patients compared to unaffected siblings and controls. Effect of interaction between T allele and CT exposure on FKBP5 demethylation was found in controls. No effect of both risk factors (T allele and CT) on FKBP5 methylation level was found in unaffected siblings. We confirmed previous evidence of the association between the FKBP5 rs1360780 T allele, CT, and decreased FKBP5 methylation in intron 7. Allele-specific FKBP5 demethylation found in patients could shed a light on altered HPA axis activity in a subgroup of patients related to stress-induced psychosis. FKBP5 methylation and potential protective mechanisms in unaffected siblings after trauma exposure require further investigation.

Analytical bias of automated immunoassays for six serum steroid hormones assessed by LC-MS/MS.

INTRODUCTION: There is a growing amount of evidence showing the significant analytical bias of steroid hormone immunoassays, but large number of available immunoassays makes conduction of a single comprehensive study of this issue hardly feasible. Aim of this study was to assess the analytical bias of six heterogeneous immunoassays for serum aldosterone, cortisol, dehydroepiandrosterone sulphate (DHEAS), testosterone, 17-hydroxyprogesterone (OHP) and progesterone using the liquid chromatography coupled to the tandem mass spectrometry (LC-MS/MS). MATERIALS AND METHODS: This method comparison study included 49 serum samples. Testosterone, DHEAS, progesterone and cortisol immunoassays were performed on the Abbott Architect i2000SR or Alinity i analysers (Abbott Diagnostics, Chicago, USA). DiaSorin's Liaison (DiaSorin, Saluggia, Italy) and DIAsource's ETI-Max 3000 analysers (DIAsource ImmunoAssays, Louvain-La-Neuve, Belgium) were chosen for aldosterone and OHP immunoassay testing, respectively. All immunoassays were evaluated against the LC-MS/MS assay relying on the commercial kit (Chromsystems, Gräfelfing, Germany) and LCMS-8050 analyser (Shimadzu, Kyoto, Japan). Analytical biases were calculated and method comparison was conducted using weighted Deming regression analysis. RESULTS: Depending on the analyte and specific immunoassay, mean relative biases ranged from -31 to + 137%. Except for the cortisol, immunoassays were positively biased. For none of the selected steroids slope and intercept 95% confidence intervals simultaneously contained 0 and 1, respectively. CONCLUSIONS: Evaluated immunoassays failed to satisfy requirements for methods' comparability and produced significant analytical biases in respect to the LC-MS/MS assay, especially at low concentrations.

Test results comparison and sample stability study: is the BD Barricor tube a suitable replacement for the BD RST tube?

INTRODUCTION: The aim was to evaluate the BD Barricor tubes by comparison with the BD Rapid Serum Tubes (RST) through measuring 25 analytes and monitoring sample stability after 24 hours and 7 days. MATERIALS AND METHODS: Samples of 52 patients from different hospital departments were examined. Blood was collected in BD RST and BD Barricor tubes (Becton, Dickinson and Company, Franklin Lakes, USA). Analytes were measured by Beckman Coulter AU 480 (Beckman Coulter, Brea, USA), Dimension EXL (Siemens Healthcare Diagnostics, Newark, USA) and ARCHITECT i2000SR (Abbott Diagnostics, Lake Forest, USA). Between-tube comparison for each analyte was performed, along with testing analyte stability after storing samples at 4 °C. RESULTS: BD Barricor tubes showed unacceptable bias compared to BD RST tubes for potassium (K) (- 4.5%) and total protein (4.4%). Analyte stability after 24 hours was acceptable in both tested tubes for most of analytes, except for glucose, aspartate aminotransferase (AST) and lactate dehydrogenase (LD) in BD Barricor and free triiodothyronine in BD RST sample tubes. Analyte stability after 7 days was unacceptable for sodium, K, calcium, creatine kinase isoenzyme MB, AST, LD and troponin I in both samples; additionally for glucose, alkaline phosphatase and albumin in BD Barricor. CONCLUSION: All analytes, except K and total protein, can be measured interchangeably in BD RST and BD Barricor tubes, applying the same reference intervals. For most of the analytes, sample re-analysis can be performed in both tubes after 24 hours and 7 days, although BD RST tubes show better 7-day analytes stability over BD Barricor tubes.

Role of Tryptophan in Microbiota-Induced Depressive-Like Behavior: Evidence From Tryptophan Depletion Study.

During the past decade, there has been a substantial rise in the knowledge about the effects of gut microbiota on host physiology and behavior, including depressive behavior. Initial studies determined that gut microbiota can regulate host tryptophan levels, which is a main serotonin precursor. A dysfunctional serotonergic system is considered to be one of the main factors contributing to the development of depression. Therefore, we hypothesized that regulation of brain tryptophan and serotonin can explain, at least partly, the effects of microbiota on depressive behavior. To test this hypothesis, we examined depressive-like behavior and brain levels of serotonin and tryptophan, of germ free (GF) and specific-pathogen free (SPF) mice under basal conditions, or after acute tryptophan depletion (ATD) procedure, which is a method to decrease tryptophan and serotonin levels in the brain. In basal conditions, GF mice exhibited less depressive-like behavior in sucrose preference, tail-suspension and forced swim tests, compared to SPF mice. In addition, in mice that were not subjected to ATD, GF mice displayed higher levels of tryptophan, serotonin and 5-hydroxyindoleacetic acid (the main degradation product of serotonin) in medial prefrontal cortex (mPFC) and hippocampus (HIPPO), compared to SPF mice. Interestingly, ATD increased depressive-like behavior of GF, but not of SPF mice. These behavioral changes were accompanied by a stronger reduction of tryptophan, serotonin and 5-hydroxyindoleacetic acid in mPFC and HIPPO in GF mice after ATD, when compared to SPF mice. Therefore, the serotonergic system of GF mice is more vulnerable to the acute challenge of tryptophan reduction, and GF mice after tryptophan reduction behave more similarly to SPF mice. These data provide functional evidence that microbiota affects depression-like behavior through influencing brain tryptophan accessibility and the serotonergic system.

Gene network analysis reveals a role for striatal glutamatergic receptors in dysregulated risk-assessment behavior of autism mouse models.

Autism spectrum disorder (ASD) presents a wide, and often varied, behavioral phenotype. Improper assessment of risks has been reported among individuals diagnosed with ASD. Improper assessment of risks may lead to increased accidents and self-injury, also reported among individuals diagnosed with ASD. However, there is little knowledge of the molecular underpinnings of the impaired risk-assessment phenotype. In this study, we have identified impaired risk-assessment activity in multiple male ASD mouse models. By performing network-based analysis of striatal whole transcriptome data from each of these ASD models, we have identified a cluster of glutamate receptor-associated genes that correlate with the risk-assessment phenotype. Furthermore, pharmacological inhibition of striatal glutamatergic receptors was able to mimic the dysregulation in risk-assessment. Therefore, this study has identified a molecular mechanism that may underlie risk-assessment dysregulation in ASD.

Antidepressants affect gut microbiota and Ruminococcus flavefaciens is able to abolish their effects on depressive-like behavior.

Accumulating evidence demonstrates that the gut microbiota affects brain function and behavior, including depressive behavior. Antidepressants are the main drugs used for treatment of depression. We hypothesized that antidepressant treatment could modify gut microbiota which can partially mediate their antidepressant effects. Mice were chronically treated with one of five antidepressants (fluoxetine, escitalopram, venlafaxine, duloxetine or desipramine), and gut microbiota was analyzed, using 16s rRNA gene sequencing. After characterization of differences in the microbiota, chosen bacterial species were supplemented to vehicle and antidepressant-treated mice, and depressive-like behavior was assessed to determine bacterial effects. RNA-seq analysis was performed to determine effects of bacterial treatment in the brain. Antidepressants reduced richness and increased beta diversity of gut bacteria, compared to controls. At the genus level, antidepressants reduced abundances of Ruminococcus, Adlercreutzia, and an unclassified Alphaproteobacteria. To examine implications of the dysregulated bacteria, we chose one of antidepressants (duloxetine) and investigated if its antidepressive effects can be attenuated by simultaneous treatment with Ruminococcus flavefaciens or Adlercreutzia equolifaciens. Supplementation with R. flavefaciens diminished duloxetine-induced decrease in depressive-like behavior, while A. equolifaciens had no such effect. R. flavefaciens treatment induced changes in cortical gene expression, up-regulating genes involved in mitochondrial oxidative phosphorylation, while down-regulating genes involved in neuronal plasticity. Our results demonstrate that various types of antidepressants alter gut microbiota composition, and further implicate a role for R. flavefaciens in alleviating depressive-like behavior. Moreover, R. flavefaciens affects gene networks in the brain, suggesting a mechanism for microbial regulation of antidepressant treatment efficiency.

Convergence of glycogen synthase kinase 3ß and GR signaling in response to fluoxetine treatment in chronically stressed female and male rats.

Accumulating evidence strongly suggest that impaired glucocorticoid receptor (GR) signaling is involved in stress-related mood disorders, and nominate GR as a potential target for antidepressants (ADs). It is known that different classes of ADs affects the GR action via modifying its phosphorylation, while the mechanism through which ADs alter GR phosphorylation targeted by GSK3ß, a kinase modulated via serotonin neurotransmission, are unclear. On this basis, we investigated whether GSK3ß-GR signaling could be a convergence point of fluoxetine action on brain function and behavior, by examining its effect on GSK3ß targeted-GR phosphorylation on threonine 171 (pGR171), and expression of GR-regulated genes in the hippocampus of female and male rats exposed to chronic isolation stress. Stress induced sex-specific GSK3ß-targeted phosphorylation of pGR171 in the nucleus of the hippocampus of stressed animals. Namely, while in females stress triggered coupled action of GSK3ß-pGR171 signaling, in males changes in pGR171 levels did not correspond to GSK3ß activity. On the other hand, fluoxetine managed to up-regulate this pathway in sex-unbiased manner. Furthermore, fluoxetine reverted stress-induced changes in most of the analyzed genes in males, CRH, 5-HT1a and p11, while in females its effect was limited to CRH. These data further suggest that pGR171 signaling affects cellular localization of GR in response to chronic stress and fluoxetine in both sexes. Collectively, our results describe a novel convergence point between GR signaling and GSK3ß pathway in rat hippocampus in response to stress and fluoxetine in both sexes and its involvement in fluoxetine-regulated brain function in males.

Distinct modifications of hippocampal glucocorticoid receptor phosphorylation and FKBPs by lipopolysaccharide in depressive female and male rats.

Inflammation plays a critical role in pathogenesis of depression and can affect the hypothalamic-pituitary-adrenal axis activity. Accordingly, in this study we investigated the role of hippocampal glucocorticoid receptor in mediating the effects of inflammation on behaviour of female and male Wistar rats. We studied the effects of lipopolysaccharide on the levels of glucocorticoid receptors and its co-chaperones FK506 binding protein 52 and FK506 binding protein 51, the levels of glucocorticoid receptor phospho-isoforms, pGR-232 and pGR-246, and glucocorticoid receptor up-stream kinases. In order to assess transcriptional activity of glucocorticoid receptor, we measured mRNA levels of several glucocorticoid receptor-regulated genes. We demonstrated that lipopolysaccharide induced depressive-like behaviour and elevated serum corticosterone in both sexes. However, it affected glucocorticoid receptor signalling in the nucleus of females and males differently - in females it elevated levels of glucocorticoid receptors, pGR-246 and FK506 binding protein 52, while in males it decreased levels of glucocorticoid receptor, both co-chaperons and pGR-246. Alterations in pGR-246 were associated with alterations of c-Jun N-terminal kinases. Altered nuclear levels of total glucocorticoid receptors and pGR-246 were accompanied by sex-specific reduction in brain-derived neurotrophic factor and cyclooxygenase-2 mRNA and sex-unspecific reduction in the expression of p11 and glucocorticoid receptor genes. These alterations may ultimately affect different glucocorticoid receptor -associated processes involved in depressive-like behaviour in males and females.

Falsely elevated serum oestradiol due to exemestane therapy.

In this study, we present a case of falsely elevated oestradiol (E2) concentration, determined by two immunoassays, in a breast cancer patient receiving exemestane therapy. The positive bias of immunochemical measurements was revealed using liquid chromatography tandem mass spectrometry which showed undetectable E2 concentration. The discrepancy is expected to be a consequence of the structural resemblance of E2 and exemestane sharing the same steroidal backbone. Inaccurate laboratory findings in therapy monitoring, as in this case, may lead to unnecessary changes of therapy.