Familial Psychosis Associated With a Missense Mutation at MACF1 Gene Combined With the Rare Duplications DUP3p26.3 and DUP16q23.3, Affecting the CNTN6 and CDH13 Genes

Role of microtubule actin crosslinking factor 1 (MACF1) in bipolar disorder pathophysiology and potential in lithium therapeutic mechanism

Bipolar affective disorder (BPAD) are life-long disorders that account for significant morbidity in afflicted patients. The etiology of BPAD is complex, combining genetic and environmental factors to increase the risk of disease. Genetic studies have pointed toward cytoskeletal dysfunction as a potential molecular mechanism through which BPAD may arise and have implicated proteins that regulate the cytoskeleton as risk factors. Microtubule actin crosslinking factor 1 (MACF1) is a giant cytoskeletal crosslinking protein that can coordinate the different aspects of the mammalian cytoskeleton with a wide variety of actions. In this review, we seek to highlight the functions of MACF1 in the nervous system and the molecular mechanisms leading to BPAD pathogenesis. We also offer a brief perspective on MACF1 and the role it may be playing in lithium's mechanism of action in treating BPAD.

Sonic hedgehog pathway as a new target of atypical antipsychotics: Revisiting of amisulpride and aripiprazole effects in a rat model of schizophrenia

OBJECTIVES

Schizophrenia is a chronic mental illness presented by cognitive deficits that precede its positive and negative symptoms. Sonic hedgehog (Shh)-pathway contributes to its pathophysiology. Shh has a role in neurogenesis as it regulates proliferation and survival of neural cells. In this study, effects of the anti-psychotics Amisulpride and/or Aripiprazole on the Shh-pathway and its relation to cognitive functions and neurogenesis in a rat model of schizophrenia were tested.

METHODS

60 male Wistar rats were allocated into the following groups: control, socially isolated, amisulpride and/or aripiprazole-treated groups. Rats were then subjected to behavioral, biochemical, and histopathological tests to assess the impact of these drugs on Shh-pathway.

KEY FINDINGS

Cognitive-dysfunction was evidenced in socially isolated group in novel object, three-chamber, and Morris water maze tests, associated by disorganised Shh-pathway proteins levels concentrations, increased glial fibrillary acidic protein (GFAP)-stained astrocytes. Treated groups favorably reversed these changes evidenced by increased Shh, transmembrane patched-1 and smoothened, glioma-associated-oncogene (GLI)-1 levels, dopamine-1 receptors and brain derived neurotrophic factor, and decreased GLI-3 protein, GFAP immune reaction in astrocytes and inflammatory markers compared to socially isolated group.

CONCLUSION

Amisulpride and/or aripiprazole have a favorable role in turning on Shh-pathway with subsequent beneficial cognitive and neurogenesis effects.

Exome sequencing of Japanese schizophrenia multiplex families supports the involvement of calcium ion channels

Background

Most sequencing studies of schizophrenia (SCZ) have focused on de novo genetic variants due to interpretability. However, investigating shared rare variants among patients in the same multiplex family is also important. Relatively large-scale analyses of SCZ multiplex families have been done in Caucasian populations, but whether detected variants are also pathogenic in the Japanese population is unclear because of ethnic differences in rare variants.

Materials and methods

We performed whole-exome sequencing (WES) of 14 Japanese SCZ multiplex families. After quality control and filtering, we identified rare variants shared among affected persons within the same family. A gene ontology (GO) analysis was performed to identify gene categories possibly affected by these candidate variants.

Results

We found 530 variants in 486 genes as potential candidate variants from the 14 SCZ multiplex families examined. The GO analysis demonstrated significant enrichment in calcium channel activity.

Conclusion

This study provides supporting evidence that calcium ion channel activity is involved in SCZ. WES of multiplex families is a potential means of identifying disease-associated rare variants for SCZ.