Calcium channel blockers for antipsychotic-induced tardive dyskinesia

Effect of rs1108580 of DBH and rs1006737 of CACNA1C on Cognition and Tardive Dyskinesia in a North Indian Schizophrenia Cohort

Genetic perturbations in dopamine neurotransmission and calcium signaling pathways are implicated in the etiology of schizophrenia. We aimed to test the association of a functional splice variant each in Dopamine β-Hydroxylase (DBH; rs1108580) and Calcium voltage-gated channel subunit alpha1 C (CACNA1C; rs1006737) genes in these pathways with schizophrenia (506 cases, 443 controls); Abnormal Involuntary Movement Scale (AIMS) scores in subjects assessed for tardive dyskinesia (76 TD-positive, 95 TD-negative) and Penn Computerized Neurocognitive Battery (PennCNB) scores (334 cases, 234 controls). The effect of smoking status and SNP genotypes on AIMS scores were assessed using ANOVA; health status and SNP genotypes on three performance functions of PennCNB cognitive domains were assessed by ANCOVA with age and sex as covariates. Association with Positive and Negative Syndrome Scale (PANSS) scores in the TD cohort and cognitive scores in healthy controls of the cognition cohort were tested by linear regression. None of the markers were associated with schizophrenia. Smoking status [F(2, 139) = 10.6; p = 5 × 10-5], rs1006737 [F(2, 139) = 7.1; p = 0.001], TD status*smoking [F(2, 139) = 8.0; p = 5.0 × 10-4] and smoking status*rs1006737 [F(4, 139) = 2.7; p = 0.03] had an effect on AIMS score. Furthermore, rs1006737 was associated with orofacial [F(2, 139) = 4.6; p = 0.01] and limb-truncal TD [(F(2, 139) = 3.8; p = 0.02]. Main effect of rs1108580 on working memoryprocessing speed [F(2, 544) = 3.8; p = 0.03] and rs1006737 on spatial abilityefficiency [F(1, 550) = 9.4; p = 0.02] was identified. Health status*rs1006737 interaction had an effect on spatial memoryprocessing speed [F(1, 550) = 6.9; p = 0.01]. Allelic/genotypic association (p = 0.01/0.03) of rs1006737 with disorganized/concrete factor and allelic association of rs1108580 (p = 0.04) with a depressive factor of PANSS was observed in the TD-negative subcohort. Allelic association of rs1006737 with sensorimotor dexterityaccuracy (p = 0.03), attentionefficiency (p = 0.05), and spatial abilityefficiency (p = 0.02); allelic association of rs1108580 with face memoryaccuracy (p = 0.05) and emotionefficiency (p = 0.05); and allelic/genotypic association with emotionaccuracy (p = 0.003/0.009) were observed in healthy controls of the cognition cohort. These association findings may have direct implications for personalized medicine and cognitive remediation.

Movement disorders of the mouth: a review of the common phenomenologies

Movement disorders of the mouth encompass a spectrum of hyperactive movements involving the muscles of the orofacial complex. They are rare conditions and are described in the literature primarily in case reports originating from neurologists, psychiatrists, and the dental community. The focus of this review is to provide a phenomenological description of different oral motor disorders including oromandibular dystonia, orofacial dyskinesia and orolingual tremor, and to offer management strategies for optimal treatment based on the current literature. A literature search of full text studies using PubMed/Medline and Cochrane library combined with a manual search of the reference lists was conducted until June 2021. Results from this search included meta-analyses, systematic reviews, reviews, clinical studies, case series, and case reports published by neurologists, psychiatrists, dentists and oral and maxillofacial surgeons. Data garnered from these sources were used to provide an overview of most commonly encountered movement disorders of the mouth, aiding physicians in recognizing these rare conditions and in initiating appropriate therapy.

Influence of magnesium supplementation and L-type calcium channel blocker on haloperidol-induced movement disturbances

Haloperidol (Hal) is an antipsychotic related to movement disorders. Magnesium (Mg) showed benefits on orofacial dyskinesia (OD), suggesting its involvement with N-methyl-D-aspartate receptors (NMDAR) since it acts blocking calcium channels. Comparisons between nifedipine (NIF; a calcium channel blocker) and Mg were performed to establish the Mg mechanism. Male rats concomitantly received Hal and Mg or NIF for 28 days, and OD behaviors were weekly assessed. Both Mg and NIF decreased Hal-induced OD. Hal increased Ca²⁺-ATPase activity in the striatum, and Mg reversed it. In the cortex, both Mg and NIF decreased such activity. Dopaminergic and glutamatergic immunoreactivity were modified by Hal and treatments: i) in the cortex: Hal reduced D1R and D2R, increasing NMDAR immunoreactivity. Mg and NIF reversed this Hal influence on D1R and NMDAR, while only Mg reversed Hal effects on D2R levels; ii) in the striatum: Hal decreased D2R and increased NMDAR while Mg and NIF decreased D1R and reversed the Hal-induced decreasing D2R levels. Only Mg reversed the Hal-induced increasing NMDAR levels; iii) in the substantia nigra (SN): while Hal increased D1R, D2R, and NMDAR, both Mg and NIF reversed this influence on D2R, but only Mg reversed the Hal-influence on D1R levels. Only NIF reversed the Hal effects on NMDAR immunoreactivity. These findings allow us to propose that Mg may be useful to minimize Hal-induced movement disturbances. Mg molecular mechanism seems to be involved with a calcium channel blocker because the NIF group showed less expressive effects than the Mg group.

Study-based registers reduce waste in systematic reviewing: discussion and case report

BACKGROUND

Maintained study-based registers (SBRs) have, at their core, study records linked to, potentially, multiple other records such as references, data sets, standard texts and full-text reports. Such registers can minimise and refine searching, de-duplicating, screening and acquisition of full texts. SBRs can facilitate new review titles/updates and, within seconds, inform the team about the potential workload of each task.

METHODS

We discuss the advantages/disadvantages of SBRs and report a case of how such a register was used to develop a successful grant application and deliver results-reducing considerable redundancy of effort.

RESULTS

SBRs saved time in question-setting and scoping and made rapid production of nine Cochrane systematic reviews possible.

CONCLUSION

Whilst helping prioritise and conduct systematic reviews, SBRs improve quality. Those funding information specialists for literature reviewing could reasonably stipulate the resulting SBR to be delivered for dissemination and use beyond the life of the project.