Narcolepsy is a chronic sleep disorder long hypothesised to be an autoimmune disease. Complement-mediated immune mechanisms have not been investigated in detail in narcolepsy. Our aim was to establish the significance of classical pathway activation in narcolepsy.

Sera of 42 narcolepsy patients and 26 healthy controls were screened with ELISA to determine the levels of C1q, C3a, C4d and complement component 4 binding protein (C4BP). A home-made ELISA method was developed to detect antibodies to C4BP-alpha (anti-C4BPA). The correlation between complement levels and clinical findings was examined.

C1q levels were significantly higher in narcolepsy patients while C4d and C4BP levels were significantly lower compared to healthy controls. C3a levels were comparable among patients and controls. Eleven narcolepsy patients showed serum anti-C4BPA levels. Total rapid eye movements (REM) time, sleep onset latency, REM sleep latency, sleep activity, percentage of wakefulness after sleep onset and Epworth sleepiness scale scores were correlated with levels of different complement factors.

Complement-mediated immune mechanisms might partake in narcolepsy pathogenesis. The precise role of autoantibodies on complement level alterations needs to be investigated. Levels of complement factors and degradation products may potentially be utilised as biomarkers to predict the clinical severity of narcolepsy.

This study was aimed at evaluating the efficacy of glucosamine and potential mechanisms of actions in a neuropathic pain model in rats.

Glucosamine (500, 1000 and 2000 mg/kg) was administered via gavage route, 1 day before the chronic constriction injury (CCI) of sciatic nerve and daily for 14 days (prophylactic regimen), or from days 5 to 14 post-injury (therapeutic regimen), as the indicators of neuropathic pain, mechanical allodynia, cold allodynia and thermal hyperalgesia were assessed on days 0, 3, 5, 7, 10 and 14 after ligation. Inducible nitric oxide synthase (iNOS) and tumour necrosis factor alpha (TNF-α) gene expressions were measured by real-time polymerase chain reaction. TNF-α protein content was measured using the enzyme-linked immunosorbent assay method.

Three days after nerve injury, the threshold of pain was declined among animals subjected to neuropathic pain. Mechanical and cold allodynia, as well as thermal hyperalgesia were attenuated by glucosamine (500, 1000, 2000 mg/kg) in the prophylactic regimen. However, existing pain was not decreased by this drug. Increased mRNA expression of iNOS and TNF-α was significantly reduced in the spinal cord of CCI animals by glucosamine (500, 1000, 2000 mg/kg) in the prophylactic regimen. The overall expression of spinal TNF-α was increased by CCI, but this increase was reduced in animals receiving glucosamine prophylactic treatment.

Findings suggest that glucosamine as a safe supplement may be a useful candidate in preventing neuropathic pain following nerve injury. Antioxidant and anti-inflammatory effects may be at least in part responsible for the antinociceptive effects of this drug.

The coronavirus disease 2019 (COVID-19) pandemic and the necessary social isolation and distancing measures – that were adopted to prevent spreading the virus, including the suspension of university classes – negatively impacted the mental health of young adults. The aim of the current study was to investigate whether returning to online classes, even not presential, during the social isolation of the COVID-19 pandemic, affected the mental health of university students.

Forty students (10 men and 30 women) (age, 22.3 ± 3.8 years; body mass, 62.5 ± 17.8 kg; height, 165.6 ± 8.7 cm) from undergraduate health courses participated in the study. The students answered a self-administered questionnaire designed to gather personal and quarantine information as well as information about the frequency of depression (PHQ-9) and anxiety (GAD-7) symptoms. The questionnaire was answered before and after the return to online classes.

There was a significantly lower frequency of depression symptoms after the return to online classes (Z = −2.27; p = 0.02). However, there was no difference in anxiety symptoms before and after returning to online classes (Z = −0.51; p = 0.61).

Return to online classes positively impacted the mental health (decrease of frequency of depression symptoms) of university students. Future studies are needed to observe whether the changes observed after returning to school are maintained over time.

The aim of this study was to investigate the possible impact of the Covid-19 pandemic on general health, mental well-being, and experiences of control compared to pre-pandemic populations. Our hypotheses were that we would observe a significantly lower level of psychological well-being and general health in the 2020 sample compared to the pre-pandemic samples, and that we would observe younger age groups to be the most affected.

Two representative Danish populations (2016, n = 1656) and (2017, n = 3366) were compared to a representative Danish population (2020, n = 1538) sampled during the first lockdown in May 2020. Two-tailed tests of proportions were used to investigate possible differences between samples in proportions reporting poorer mental well-being measured by 5-item World Health Organization Well-Being Index, general health, and internal locus of control.

Younger men (aged 18–24) and younger women (aged 18–44) as well as elderly women (aged 65–74) reported lower mental well-being during the early phase of the pandemic compared to the population from 2016. Both women and men in 2020 reported significantly lower levels of internal locus of control compared to the 2017 sample. This was especially true for younger men and women. There were no statistically significant differences in general health between populations.

This study partly supports the hypothesis that the Covid-19 pandemic affected mental well-being negatively among younger persons. However, longitudinal studies are needed to investigate possible long-term effects of the pandemic on mental health and well-being. Further, qualitative studies are needed to investigate the in-depth consequences of Covid-19.

Sensorimotor gating is experimentally operationalized by the prepulse inhibition (PPI) of the startle response (SR). Previous studies suggest high test-retest reliability of PPI and potential correlation with working memory (WM). Here, we aimed to validate and extend the test-retest reliability of PPI in healthy humans and its correlation with WM performance.

We applied an acoustic startle PPI paradigm with four different prepulse intensities (64, 68, 72 and 76 dB) and two different WM tasks [n-back, change detection task (CDT)] in a group of 26 healthy adults (final sample size n = 23). To assess test-retest reliability, we performed all tests on two separate days ~27 days (range: 21–32 days) apart.

We were able to confirm high test-retest reliability of the PPI with a mean intraclass correlation (ICC) of > 0.80 and significant positive correlation of PPI with n-back but not with CDT performance. Detailed analysis showed that PPI across all prepulse intensities significantly correlated with both the 2-back and 0-back conditions, suggesting regulation by cross-conditional processes (e.g. attention). However, when removing the 0-back component from the 2-back data, we found a specific and significant correlation with WM for the 76-dB PPI condition.

With the present study, we were able to confirm the high test-retest reliability of the PPI in humans and could validate and expand on its correlation with WM performance.

S100B is a glial cell protein with bimodal function. In low concentrations, it exerts neurotrophic effects, but higher levels reflect neuronal distress. Recent research suggests that this molecule may be a biomarker of response to electroconvulsive therapy (ECT). We examined the effect of ECT on serum S100B and its utility as 1) a biomarker of a depressive state and 2) a predictor of ECT response. We also wanted to ensure that ECT does not cause a marked serum S100B elevation, indicating neural distress.

We measured serum S100B in 22 in-patients treated with ECT due to depression. Depression severity was assessed using 17-item Hamilton Rating Scale for Depression (HAMD-17). The data were collected before an ECT series, within 1 week after the series (post-ECT), and at a 6-month follow-up. Changes in serum S100B and clinical outcomes were tested using a linear mixed model. A relationship between serum S100B and the clinical outcomes was examined using Spearman’s and partial correlation.

Serum S100B did not change significantly immediately after an ECT series or 6 months later. The post-ECT serum S100B change was not associated with the clinical effect (rho = 0.14, n = 22, p = 0.54). The baseline serum S100B did not predict the clinical effect when controlling for age (r = 0.02, n = 22, df = 19, p = 0.92).

The study neither supports serum S100B as a state marker of depression nor a predictor of ECT response. No evidence for ECT-related neural distress was found.

Several studies have reported that the pandemic of coronavirus disease 2019 (COVID-19) influenced cognitive function in the elderly. However, the effect of COVID-19-related fear on brain atrophy has not been evaluated. In this study, we evaluated the relation between brain atrophy and the effect of COVID-19-related fear by analysing changes in brain volume over time using magnetic resonance imaging (MRI).

Participants were 25 Japanese patients with mild cognitive impairment (MCI) or subjective cognitive decline (SCD), who underwent 1.5-tesla MRI scan twice, once before and once after the pandemic outbreak of COVID-19, and the Fear of Coronavirus Disease 2019 Scale (FCV-19S) assessment during that period. We computed regional brain atrophy per day between the 1st and 2nd scan, and evaluated the relation between the FCV-19S scores and regional shrinkage.

There was significant positive correlation between the total FCV-19S score and volume reduction per day in the right posterior cingulate cortex. Regarding the subscales of FCV-19S, we found significant positive correlation between factor 2 of the FCV-19S and shrinkage of the right posterior cingulate cortex.

There was positive correlation between the FCV-19S score and regional brain atrophy per day. Although it is already known that the psychological effects surrounding the COVID-19 pandemic cause cognitive function decline, our results further suggest that anxiety and fear related to COVID-19 cause regional brain atrophy.

Acetylcholinesterase inhibitors are the focus of interest in the management of schizophrenia. We aimed to investigate the effects of acute galangin administration, a flavonoid compound with acetylcholinesterase inhibiting activity, on schizophrenia-associated cognitive deficits in rats and schizophrenia models in mice.

Apomorphine-induced prepulse inhibition (PPI) disruption for cognitive functions, nicotinic, muscarinic, and serotonergic mechanism involvement, and brain acetylcholine levels were investigated in Wistar rats. Apomorphine-induced climbing, MK-801-induced hyperlocomotion, and catalepsy tests were used as schizophrenia models in Swiss albino mice. The effects of galangin were compared with acetylcholinesterase inhibitor donepezil, and typical and atypical antipsychotics haloperidol and olanzapine, respectively.

Galangin (50,100 mg/kg) enhanced apomorphine-induced PPI disruption similar to donepezil, haloperidol, and olanzapine (p < 0.05). This effect was not altered in the combination of galangin with the nicotinic receptor antagonist mecamylamine (1 mg/kg), the muscarinic receptor antagonist scopolamine (0.05 mg/kg), or the serotonin-1A receptor antagonist WAY-100635 (1 mg/kg) (p > 0.05). Galangin (50,100 mg/kg) alone increased brain acetylcholine concentrations (p < 0.05), but not in apomorphine-injected rats (p > 0.05). Galangin (50 mg/kg) decreased apomorphine-induced climbing and MK-801-induced hyperlocomotion similar to haloperidol and olanzapine (p < 0.05), but did not induce catalepsy, unlike them.

We suggest that galangin may help enhance schizophrenia-associated cognitive deficits, and nicotinic, muscarinic cholinergic, and serotonin-1A receptors are not involved in this effect. Galangin also exerted an antipsychotic-like effect without inducing catalepsy and may be considered as an advantageous antipsychotic agent.

Social distancing to limit COVID-19 transmission has led to extensive lifestyle changes, including for people with dementia (PWD). The aim of this study, therefore, was to assess the impact of lockdown on the mental health of PWD and their carers.

Forty-five carers of PWD completed a telephone interview during the baseline assessment of the SOLITUDE study to gather information on life conditions and changes in symptoms of PWD during lockdown. Associations between changes in symptoms of PWD and carers’ concerns and mental health were investigated.

About 44% of carers experienced anxiety and irritability and reported changes in behavioural and cognitive symptoms in PWD. These changes were associated with worse carers’ mental health and concerns about faster disease progression (χ2 = 13.542, p < 0.001).

COVID-19-related social isolation has had a negative impact on patients’ and carers’ mental health. Potential long-term neurocognitive consequences require further investigation.

It has been postulated that neurotrophin dysregulation leads to disorganisation in neuronal networks, which results in schizophrenia. The current study sets out to evaluate if the finding of lower brain-derived neurotrophic factor (BDNF) levels in schizophrenia patients could be confirmed in an independent cohort and to investigate if the BDNF levels can be altered with different treatment modalities such as electroconvulsive therapy (ECT) and/or antipsychotic pharmacotherapy (PT).

A total of 54 male patients with schizophrenia and 35 healthy controls were included in the study. Schizophrenia patients were subdivided into two groups as the ones who underwent ECT + PT and only PT. Clinical and sociodemographic data questionnaire, Positive and Negative Syndrome Scale (PANSS) and blood sample collection for BDNF assessment were applied to all patients (on first and last days of admissions) and healthy participants (on the day of the interview). Then, clinical parameters and blood sample outcomes were statistically analysed.

Mean BDNF levels of healthy individuals were significantly higher than mean pre- and post-treatment BDNF levels in both PT only and ECT + PT groups. While serum BDNF levels did not increase after ECT + PT, there was a trend level increase in the PT only group. There was no significant correlation between the changes in serum BDNF levels with total PANSS scores in either group after treatment.

We could confirm previously suggested data of lower serum BDNF levels in schizophrenia patients compared to healthy population but we could not find significant increase in serum BDNF levels with ECT + PT or only PT as some previous studies suggested.

Autoimmune mechanisms are related to disease development in a subgroup of patients with psychosis. The contribution of immunoglobulin G (IgG) antibodies against myelin oligodendrocyte glycoprotein (MOG) is mainly unclear in this context.

Therefore, two patients with psychosis and anti-MOG antibodies – detected in fixed cell-based and live cell-based assays – are presented.

Patient 1 suffered from late-onset psychosis with singular white matter lesions in magnetic resonance imaging (MRI) and intermittent electroencephalography (EEG) slowing. Patient 2 suffered from a chronic paranoid–hallucinatory disorder with intermittent confusional states, non-specific white matter alterations on MRI, a disorganised alpha rhythm on EEG, and elevated cerebrospinal fluid protein. Both patients had anti-MOG antibody titres of 1 : 320 in serum (reference < 1 : 20).

The arguments for and against a causal role for anti-MOG antibodies are discussed. The antibodies could be relevant, but due to moderate titres, they may have caused a rather ‘subtle clinical picture’ consisting of psychosis instead of ‘classical’ MOG encephalomyelitis.

Akathisia is among the most unpleasant side effects related to antipsychotic drug (AP) use, and possible associations between akathisia and agitation, depression and suicidal behaviour, respectively, have been described in previous literature. New generation antipsychotics are however regarded less prone to induce this particular adverse effect compared to older drugs, but evidence is incomplete and in need of confirmation from clinically relevant samples and settings. We, therefore, aim to investigate akathisia at hospital discharge for patients consecutively admitted with acute-phase psychosis and treated with atypical antipsychotics according to guideline-concordant clinical practice.

This exploratory study is part of a naturalistic randomised controlled study in patients admitted with acute phase psychosis (N = 109). We report cross-sectional data at discharge/first follow-up after acute psychiatric hospital admission for patients with schizophrenia and related psychotic disorders.

There were statistically significant positive associations between akathisia and the following; suicidality in men (Beta 0.306, p = 0.048), but not in women; agitation in those previously unexposed to antipsychotics (Beta 0.288, p = 0.047) and depression in those exposed to antipsychotics before hospital admittance (Beta 0.375, p = 0.031).

Main findings were that akathisia is still a prevalent side effect in a clinically relevant sample of patients treated with atypical antipsychotics. Our results suggest that akathisia is significantly associated with depression, suicidality and agitation in different subgroups of patients receiving APs. Akathisia can be detrimental and the relations between akathisia and depression, suicidality and agitation should be investigated further in prospective, hypothesis-testing studies with larger samples.