Some clinical studies have reported reduced peripheral glial cell line-derived neurotrophic factor (GDNF) level in elderly patients with major depressive disorder (MDD). We verified whether a reduction in plasma GDNF level was associated with MDD.

Plasma GDNF level was measured in 23 healthy control subjects and 23 MDD patients before and after 6 weeks of treatment.

Plasma GDNF level in MDD patients at baseline did not differ from that in healthy controls. Plasma GDNF in MDD patients did not differ significantly from baseline to the end of treatment. GDNF level was significantly lower in recurrent-episode MDD patients than in first-episode patients before and after treatment.

Our findings revealed significantly lower plasma GDNF level in recurrent-episode MDD patients, although plasma GDNF levels in MDD patients and healthy controls did not differ significantly. The discrepancy between our study and previous studies might arise from differences in the recurrence of depression or the ages of the MDD patients.

Glutamatergic neurotransmission via the N-methyl-d-aspartate (NMDA) receptor is integral to the pathophysiology of depression. This study was performed to examine whether amino acids related to NMDA receptor neurotransmission are altered in the serum of patients with depression.

We measured the serum levels of d-serine, l-serine, glycine, glutamate and glutamine in patients with depression (n=70), and age-matched healthy subjects (n=78).

Serum levels of d-serine and l-serine in patients with depression were significantly higher than those of healthy controls (p<0.001). In contrast, serum levels of glycine, glutamate and glutamine did not differ between the two groups. Interestingly, the ratio of l-serine to glycine in patients was significantly higher than that of healthy controls (p<0.001).

This study suggests that serine enantiomers may be peripheral biomarkers for depression, and that abnormality in the d-serine-l-serine-glycine cycle plays a role in the pathophysiology of depression.

Among the 28 metalloproteinases described so far, 23 can be found in the human organism, but only few are expressed in the human brain. The main objective of this study was to analyse the relationship between MMP-2, MMP-9 and TIMP-2 gene expression and cognitive performance.

The study comprised 234 subjects: patients suffering from recurrent depressive disorder (rDD, n=139) and healthy subjects (HS, n=95). The cognitive function assessment was carried out with the help of the following tests: Trail Making Test, The Stroop Test, Verbal Fluency Test and Auditory Verbal Learning Test. Gene expression on the mRNA and protein level was evaluated for MMP-2, MMP-9 and TIMP-2 in both groups using RNA extraction, reverse transcription and enzyme-linked immunosorbent assay.

Both mRNA and protein expression levels of all the genes were significantly lower in rDD subjects as compared with HS. Having analysed the entire experimental group (N=234), significant interrelations were found between the expression of the analysed genes and the results of the tests used to measure cognitive functions. Increased expression on both the mRNA and the protein level was associated in each case with better performance of all the tests conducted. After carrying out a separate analysis on the people from the rDD group and the HS group, similar dependencies were still observed.

The results of our study show decreased expression of MMP-2, MMP-9 and TIMP-2 genes on both mRNA and protein levels in depression. Elevated expression of MMP-2, MMP-9, TIMP-2 positively affects cognitive efficiency: working memory, executive functions, attention functions, direct and delayed auditory–verbal memory, the effectiveness of learning processes and verbal fluency. The study highlights the important role of peripheral matrix metalloproteinases genes in depression and cognitive functions.

Neuroimaging studies of depression considered as a stress-related disorder have shown uncoupling in regional cerebral blood flow (rCBF) and regional cerebral metabolic rate for glucose (rCMRglc). We hypothesised that the mismatch change of rCBF and rCMRglc could be a stress-related phenomenon.

We exposed male rats to 15-min period of forced swim (FS), followed by the measurement of rCBF using N-isopropyl-4-[123I] iodoamphetamine (123I-IMP) and rCMRglc using 2-deoxy-2-[18F] fluoro-D-glucose (18F-FDG).

The uptake rate of 18F-FDG in the FS group showed a significant decrease in the prefrontal cortex (0.86±0.20%ID/g, p<0.01) and thalamus (0.77±0.17%ID/g, p<0.05) and tended to be lower in the hippocampus (0.58±0.13%ID/g) and cerebellum (0.59±0.13%ID/g) without overt alteration in the uptake rate of 123I-IMP.

The FS stress can cause mismatch change of rCBF and rCMRglc, which reflect a stress-related phenomenon.

We hypothesised that men and women who engage in extreme or high-risk sports would score higher on standardised measures of bipolarity and impulsivity compared to age and gender matched controls.

Four-hundred and eighty extreme or high-risk athletes (255 males and 225 females) and 235 age-matched control persons (107 males and 128 females) were enrolled into the web-based case-control study. The Mood Disorder Questionnaire (MDQ) and Barratt Impulsiveness Scale (BIS-11) were administered to screen for bipolarity and impulsive behaviours, respectively.

Results indicated that extreme or high-risk athletes had significantly higher scores of bipolarity and impulsivity, and lower scores on cognitive complexity of the BIS-11, compared to controls. Further, there were positive correlations between the MDQ and BIS-11 scores.

These results showed greater rates of bipolarity and impulsivity, in the extreme or high-risk athletes, suggesting these measures are sensitive to high-risk behaviours.

The precise aetiology of schizophrenia remains unclear. The neurodevelopmental hypothesis of schizophrenia has been proposed based on the accumulation of genomic or neuroimaging studies.

In this study, we examined the catecholaminergic neuronal networks in the frontal cortices of disrupted-in-schizophrenia 1 (DISC1) knockout (KO) mice, which are considered to be a useful model of schizophrenia.

Six DISC1 homozygous KO mice and six age-matched littermates were used. The animals’ brains were cut into 20-μm-thick slices, which were then immunohistochemically stained using an anti-tyrosine hydroxylase (TH) monoclonal antibody.

The TH-immunopositive fibres detected in the orbitofrontal cortices of the DISC1 KO mice were significantly shorter than those seen in the wild-type mice.

These neuropathological findings indicate that the hypofrontal symptoms of schizophrenia are associated with higher mental function deficiencies or cognitive dysfunction such as a loss of working memory.

We examined Theory of Mind (ToM) abilities in adolescents with early-onset schizophrenia (EOS) and their correlation with clinical findings and Executive Functions (EF).

The ToM abilities of 12 adolescents with EOS were compared with those of healthy participants matched in age and educational level. The Moving Shapes Paradigm was used to explore ToM abilities in three modalities: random movement, goal-directed movement and ToM – scored on the dimensions of intentionality, appropriateness and length of each answer. EF was tested using Davidson’s Battery and the clinical psychopathology with the Positive and Negative Syndrome Scale (PANSS).

Adolescents with EOS were significantly more impaired than controls in the three dimensions evaluated for the goal-directed and ToM modalities. Regarding the random movement modality, the only difference was in appropriateness (p<0.01). No correlation with age or level of education was evident for ToM skills. Total PANSS score was negatively correlated with appropriateness score for the goal-directed (p=0.02) and ToM modalities (p=0.01). No correlation existed between performance in the ToM Animated Tasks and positive, negative or disorganisation PANSS subscores. No correlations were found among the three scores in the Moving Shapes Paradigm and any measures of the accuracy of the three tasks assessing EF.

Our results confirm previous findings of ToM deficits in adult individuals with schizophrenia and attest the severity of these deficits in patients with EOS.

Treatment-resistant depression is a challenging problem in the clinical setting. Tipepidine has been used as a non-narcotic antitussive in Japan since 1959.

We administered tipepidine to 11 patients with treatment-resistant depression. Tipepidine was given for 8 weeks as an augmentation.

Tipepidine significantly improved depression scores on the Hamilton Rating Scale for depression. Add-on treatment with tipepidine significantly improved scores on the trail making test and Rey auditory verbal learning test. However, no changes were observed in blood concentrations of stress-related hormones (adrenocorticotropic hormone, cortisol, dehydroepiandrosterone sulphate) with tipepidine augmentation.

Tipepidine might be a potential therapeutic drug for treatment-resistant depression.

Immune system activation is involved in the pathophysiology of panic disorder (PD). We investigated INF-γ+874 A/T, TNF-α-308 G/A, and IL-10-1082 G/A single nucleotide polymorphisms (SNPs) to determine their association with PD.

This study enroled 135 PD patients and 135 healthy controls. INF-γ+874 A/T (rs2430561), TNF-α-308 G/A (rs1800629), and IL-10-1082 G/A (rs1800896) were genotyped.

There were no differences in genotypes or allele frequencies between the patient and control groups, regardless of accompanying agoraphobia. However, for female patients, the G allele frequency in IL-10 SNP was higher in the control group than in the patient group. Additionally, the female control group had a higher frequency of the A/G and G/G genotype in the IL-10 SNP than the female patient group.

We suggest that the G allele in IL-10-1082 G/A might have a role in reducing the manifestations of PD in female patients. Further studies are needed to extend and confirm our findings.

11β-dehydroxysteroid dehydrogenase (HSD) types 1 and 2, enzymes are involved in the activation and inactivation of glucocorticoids in vivo, respectively. Indirect evidence implicates two enzymes in the aetiology of depression but no study has directly assessed the potential role of 11 β-HSD1 in animal tests.

We assessed 11 β-HSD1 knockout mice in the forced swim test (FST), tail suspension test (TST) and for locomotor activity.

Genetic ablation of the 11β-HSD1 gene results in an antidepressant-like phenotype in the FST; the most widely utilised animal test of antidepressant activity, but not in the related TST. This may be related to the different biological substrates underlying these tests. The decreased FST immobility was not due to alterations in general activity.

Taken together these results suggest that 11β-HSD1 may play an important role in depression-related behaviours and further studies are necessary to fully characterise its role in such behaviour.

To evaluate the influence of acute restraint stress (ARS) on plasma enkephalinase and oxytocinase activities. ARS modifies basal activities in cortico-limbic regions of rats and induces changes in the correlations observed between these regions. The interactions between plasma and cortico-limbic activities will be also evaluated.

Enkephalinase (AlaAP and LeuAP) and oxytocinase (P-LeuAP) activities were fluorometrically determined in plasma of control and stressed rats using aminoacyl-β-naphthylamides (aaNNap), AlaNNap and LeuNNap as substrates.

No differences in enzymatic activities were observed between control and stressed animals in plasma. In contrast, highly significant positive and negative correlations between plasma and cortico-limbic regions were demonstrated in controls. Stress conditions significantly alter the pattern of these correlations.

The present results clearly support a connection between plasma and brain involving certain neuropeptidase activities that change under stress conditions.

After the prevalence of syphilis had reached historic lows, the Center for Disease Control devised a plan to eradicate syphilis in the United States. Since that decree there has been a dramatic rise in new cases. Psychosis is an ominous symptom of neurosyphilis.

We report a case of neurosyphilis that was misdiagnosed and staged incorrectly.

Failure to diagnose neurosyphilis was associated with prolonged psychosis that has been refractory to antipsychotic treatment.

Psychiatrists should renew their vigilance for neurosyphilis in the setting of a positive screening test and psychosis.