Pineal gland abnormality in major depressive disorder

Intranasal delivery of paroxetine: A preclinical study on pharmacokinetics, depressive-like behaviour, and neurochemical sex differences

Treatment of major depressive disorder remains a major unmet clinical need. Given the advantages of intranasal administration for targeted brain delivery, the present study aimed at investigating the pharmacokinetics of paroxetine, after its intranasal instillation and assessing its potential therapeutic effect on female and male mice subjected to unpredictable chronic mild stress (UCMS) protocol. IN administration revealed direct nose-to-brain paroxetine delivery but dose- and sex-dependent differences. Pharmacokinetics was nonlinear and paroxetine concentrations were consistently higher in plasma and brain of male mice. Additionally, UCMS decreased animal preference for sucrose in both male and female mice following acute (p < 0.01) and chronic stress (p < 0.05), suggesting anhedonia. Both male and female mice exhibited depressive-like behavior in the forced swimming test. UCMS females displayed a significantly longer immobility time and shorter climbing time than the control group (p < 0.05), while no differences were found between male mice. Two weeks of paroxetine intranasal administration reduced immobility time and lengthened climbing and swimming time, approaching values similar to those observed in the healthy control group. The therapeutic effect was stronger on female mice. Importantly, melatonin plasma levels were significantly decreased in female mice following UCMS (p < 0.05), while males exhibited heightened corticosterone levels. On the other hand, treatment with IN paroxetine significantly increased corticosterone and melatonin levels in both sexes compared to healthy mice (p < 0.05). Intranasal paroxetine delivery undoubtedly ameliorated the behavioral despair, characteristic of depressive-like animals. Despite its efficiency in male and female mice subjected to UCMS, females were more prone to this novel therapeutic strategy.

Pineal Abnormalities in Psychosis and Mood Disorders: A Systematic Review

The pineal gland (PG) is a small interhemispheric brain structure that influences human physiology in many ways, most importantly via secretion of the hormone melatonin which is known to regulate sleep and wakefulness. Here, we systematically reviewed existing neuroimaging studies of PG structure, and/or melatonin release (MLT) in psychosis and mood disorders. Medline, PubMed, and Web of Science databases were searched (on 3 February 2023), yielding 36 studies (8 PG volume, 24 MLT). The findings showed smaller-than-normal PG volume in people with schizophrenia, regardless of symptom severity and illness stage; and smaller-than-normal PG volume in major depression, with some indication of this being present only in certain subgroups, or in those with high scores on the 'loss of interest' symptom. There was considerable evidence of lower-than-normal MLT as well as aberrant MLT secretion pattern in schizophrenia. A similar picture, though less consistent than that seen in schizophrenia, emerged in major depression and bipolar disorder, with some evidence of a transient lowering of MLT following the initiation of certain antidepressants in drug-withdrawn patients. Overall, PG and MLT aberrations appear to represent transdiagnostic biomarkers for psychosis and mood disorders, but further work is needed to establish their clinical correlates and treatment implications.

Pineal morphology of the clinical high-risk state for psychosis and different psychotic disorders

BACKGROUND

Pineal volume reductions have been reported in schizophrenia and clinical high-risk states for the development of psychosis, supporting the role of melatonin dysregulation in the pathophysiology of psychosis. However, it remains unclear whether pineal volume is associated with the later onset of psychosis in individuals at clinical high-risk (CHR) of psychosis or if pineal atrophy is specific to schizophrenia among different psychotic disorders.

METHODS

This magnetic resonance imaging study examined the volume of and cyst prevalence in the pineal gland in 135 individuals at CHR of psychosis [52 (38.5%) subsequently developed psychosis], 162 with first-episode psychosis (FEP), 89 with chronic schizophrenia, and 87 healthy controls. The potential contribution of the pineal morphology to clinical characteristics was also examined in the CHR and FEP groups.

RESULTS

Pineal volumes did not differ significantly between the CHR, FEP, and chronic schizophrenia groups, but were significantly smaller than that in healthy controls. However, pineal volumes were not associated with the later onset of psychosis in the CHR group or FEP sub-diagnosis (i.e., schizophrenia, schizophreniform disorder, affective psychosis, and other psychoses). No significant differences were observed in the prevalence of pineal cysts between the groups, and it also did not correlate with clinical characteristics in the CHR and FEP groups.

CONCLUSION

These results suggest that pineal atrophy is a general vulnerability marker of psychosis, while pineal cysts do not appear to contribute to the pathophysiology of psychosis.

Features of Cognitive and Emotional Sphere of a Teenager with Epiphysis Pathology and Concomitant Speech Disorder: An Analysis of a Single Case

<p style="text-align: justify;">The study of the features of cognitive impairments in various cerebral organic pathologies allows us to understand the role of individual structures of the brain in the implementation of mental activity and determine the appropriate ways of providing psychological assistance to patients. In a situation of rare pathology, the analysis of individual clinical cases is useful. The aim of this research was to study the state of cognitive functions in a 13-year-old male teenager with a cystic restructuring of the pineal gland and concomitant undifferentiated impairment of expressive speech. Changes in the epiphysis were detected in the patient in less than a month before this psychological study. During the examination, methods of pathopsychological and neuropsychological diagnostics, and projective graphic tests were used. In the course of neuropsychological research on a teenager, a violation of the ability to compose a syllabic kinetic scheme of utterance and, in general, a lack of dynamic and kinesthetic praxis, as well as interhemispheric interaction and auditory-speech memory were revealed. The main ways of providing psychological assistance to the patient were identified: neuropsychological correction aimed at restoring impaired speech function based on preserved higher mental functions, and restoration of the communicative function of speech. The obtained results of psychological research require further understanding and verification, primarily in order to understand the pathogenesis of cognitive disorders in the situation of cystic pineal gland rearrangement.</p>

Pineal cysts without hydrocephalus: microsurgical resection via an infratentorial-supracerebellar approach-surgical strategies, complications, and their avoidance

Indications for surgery of pineal cysts without ventriculomegaly are still under debate. In view of the limited data for pineal cyst resection in the absence of hydrocephalus, and the potential risk of this approach, we have analyzed our patient cohort focusing on strategies to avoid complications according to our experience in a series of 73 pineal cyst patients. From 2003 to 2015, we reviewed our database retrospectively for all patients operated on a pineal cyst. Furthermore, we prospectively collected patients from 2016 to 2020. In summary, 73 patients with a pineal cyst were treated surgically between 2003 and 2020. All patients were operated on via a microscopic supracerebellar-infratentorial (SCIT) approach. The mean follow-up period was 26.6 months (range: 6-139 months). Seventy-three patients underwent surgery for a pineal cyst. An absence of enlarged ventricles was documented in 62 patients (51 female, 11 male, mean age 28.1 (range 4-59) years). Main presenting symptoms included headache, visual disturbances, dizziness/vertigo, nausea/emesis, and sleep disturbances. Complete cyst resection was achieved in 59/62 patients. Fifty-five of 62 (89%) patients improved after surgery with good or even excellent results according to the Chicago Chiari Outcome Scale, with complete or partial resolution of the leading symptoms. Pineal cysts resection might be an indication in certain patients for surgery even in the absence of ventriculomegaly. The high percentage of postoperative resolution of quality-of-life impairing symptoms in our series seems to justify surgery. Preoperatively, other causes of the leading symptoms have to be excluded.

Relationship between pineal gland, sleep and melatonin in fibromyalgia women: a magnetic resonance imaging study

A total of 80% of fibromyalgia (FM) population have reported poor sleep. In this regard, the pineal gland, involved in circadian rhythm processes as a key neuroendocrine organ which mainly synthesises and secretes melatonin, has never been studied before in this population. Therefore, this study aimed to evaluate the parenchyma pineal volume and its relation to sleep hours, sleep quality index and melatonin level at night. A total of 50 participants, 30 women with FM and 20 healthy control women underwent cranial magnetic resonance imaging. The total pineal volume, cyst pineal volume and parenchyma pineal volume were manually calculated in cubic millimetres. Also, the total pineal volume was estimated using Hasehawa method. Parenchyma pineal volume was significantly correlated with sleep hours (p-value = 0.041) and nocturnal melatonin level (p-value = 0.027). Moreover, there was also a non-significant correlation between parenchyma pineal volume and sleep quality index (p-value = 0.055). Furthermore, a mean parenchyma pineal volume of 102.00 (41.46) mm³ was observed, with a prevalence of 29.60% cyst in FM group. This is the first study that has reported pineal gland volumes, cyst prevalence and correlative relationships between parenchyma pineal volume and sleep hours and melatonin levels in women with FM.

Potential contribution of pineal atrophy and pineal cysts toward vulnerability and clinical characteristics of psychosis

BACKGROUND

Magnetic resonance imaging (MRI) studies reported pineal gland atrophy in schizophrenia patients and individuals at a clinical high risk of developing psychosis, implicating abnormalities in melatonin secretion in the pathophysiology of psychosis. However, it currently remains unclear whether the morphology of the pineal gland contributes to symptomatology and sociocognitive functions.

METHODS

This MRI study examined pineal gland volumes and the prevalence of pineal cysts as well as their relationship with clinical characteristics in 57 at risk mental state (ARMS) subjects, 63 patients with schizophrenia, and 61 healthy controls. The Social and Occupational Functioning Assessment Scale (SOFAS), the Schizophrenia Cognition Rating Scale (SCoRS), and the Brief Assessment of Cognition in Schizophrenia (BACS) were used to assess sociocognitive functions, while the Positive and Negative Syndrome Scale was employed to evaluate clinical symptoms in ARMS subjects and schizophrenia patients.

RESULTS

Pineal gland volumes were significantly smaller in the ARMS and schizophrenia groups than in the controls, while no significant differences were observed in the prevalence of pineal cysts. Although BACS, SCoRS, and SOFAS scores were not associated with pineal morphology, patients with pineal cysts in the schizophrenia group exhibited severe positive psychotic symptoms with rather mild negative symptoms.

CONCLUSION

The present results indicate the potential of pineal atrophy as a vulnerability marker in various stages of psychosis and suggest that pineal cysts influence the clinical subtype of schizophrenia.

[Interaction of insomnia in old age and associated diseases : Cognitive, behavioral and neurobiological aspects]

The prevalence of insomnia is particularly high in old age. Sleep disturbances and impaired daytime functioning reflected in mood swings and concentration difficulties are often accompanied by other mental disorders such as depression. The objective of this article is to shed light on the role of insomnia in the context of frequent comorbidities in middle and old age. The focus is on the identification of linkage points between insomnia and associated diseases on a neurobiological level; however, possible distinguishing features are also named and deliberations on cognitive behavioral aspects and integrative theories, such as the hyperarousal theory are discussed. In order to provide an outlook for future research opportunities, the UK Biobank is presented as a promising resource of long-term data. Finally, the contents of the preceding deliberations are critically reflected and practical implications for the treatment of older patients with insomnia are derived.

Pineal Gland Volume in Major Depressive and Bipolar Disorders

Abnormal melatonin secretion has been demonstrated in patients with affective disorders such as major depressive disorder (MDD) and bipolar disorder (BD). However, magnetic resonance imaging (MRI) studies that previously investigated the volume of the pineal gland, which regulates circadian rhythms by secreting melatonin, in these patients reported inconsistent findings. The present study employed MRI to examine pineal gland volumes and pineal cyst prevalence in 56 MDD patients (29 currently depressed and 27 remitted patients), 26 BD patients, and matched controls (33 for MDD and 24 for BD). Pineal volumes and cyst prevalence in the current MDD, remitted MDD, and BD groups did not significantly differ from those of the healthy controls. However, pineal gland volumes were significantly smaller in the current MDD subgroup of non-melancholic depression than in the melancholic MDD subgroup. Interestingly, pineal volumes correlated negatively with the severity of loss of interest in the current MDD group. Medication and the number of affective episodes were not associated with pineal volumes in the MDD or BD group. While these results do not suggest that pineal volumes reflect abnormal melatonin secretion in affective disorders, they do point to the possibility that pineal abnormalities are associated with clinical subtypes of MDD and its symptomatology.