Effect of clonazepam treatment on antipsychotic drug-induced Meige syndrome and changes in plasma levels of GABA, HVA, and MHPG during treatment

Risperidone response in patients with schizophrenia drives DNA methylation changes in immune and neuronal systems

Background: The choice of efficient antipsychotic therapy for schizophrenia relies on a time-consuming trial-and-error approach, whereas the social and economic burdens of the disease call for faster alternatives. Material & methods: In a search for predictive biomarkers of antipsychotic response, blood methylomes of 28 patients were analyzed before and 4 weeks into risperidone therapy. Results: Several CpGs exhibiting response-specific temporal dynamics were identified in otherwise temporally stable methylomes and noticeable global response-related differences were observed between good and bad responders. These were associated with genes involved in immunity, neurotransmission and neuronal development. Polymorphisms in many of these genes were previously linked with schizophrenia etiology and antipsychotic response. Conclusion: Antipsychotic response seems to be shaped by both stable and medication-induced methylation differences.

Altered coupling of resting-state cerebral blood flow and functional connectivity in Meige syndrome

Introduction

Meige syndrome (MS) is an adult-onset segmental dystonia disease, mainly manifested as blepharospasm and involuntary movement caused by dystonic dysfunction of the oromandibular muscles. The changes of brain activity, perfusion and neurovascular coupling in patients with Meige syndrome are hitherto unknown.

Methods

Twenty-five MS patients and thirty age- and sex-matched healthy controls (HC) were prospectively recruited in this study. All the participants underwent resting-state arterial spin labeling and blood oxygen level-dependent examinations on a 3.0 T MR scanner. The measurement of neurovascular coupling was calculated using cerebral blood flow (CBF)-functional connectivity strength (FCS) correlations across the voxels of whole gray matter. Also, voxel-wised analyses of CBF, FCS, and CBF/FCS ratio images between MS and HC were conducted. Additionally, CBF and FCS values were compared between these two groups in selected motion-related brain regions.

Results

MS patients showed increased whole gray matter CBF-FCS coupling relative to HC (t = 2.262, p = 0.028). In addition, MS patients showed significantly increased CBF value in middle frontal gyrus and bilateral precentral gyrus.

Conclusion

The abnormal elevated neurovascular coupling of MS may indicate a compensated blood perfusion in motor-related brain regions and reorganized the balance between neuronal activity and brain blood supply. Our results provide a new insight into the neural mechanism underlying MS from the perspective of neurovascular coupling and cerebral perfusion.

Marked Improvement of Meige Syndrome in a Japanese Male Patient with Schizophrenia After Switching from Risperidone to Paliperidone: A Case Report

Meige syndrome is a relatively rare type of oral facial dystonia. The dominant symptoms involve involuntary eye blinking and chin thrusting. Some patients may experience excessive tongue protrusion, squinting, muddled speech, or uncontrollable contraction of the platysma muscle. A 44-year-old Japanese male was suffering from schizophrenia. The initial presentation of his psychosis consisted of auditory hallucinations, delusions of persecution, psychomotor excitement, loosening association, and restlessness. After being prescribed several antipsychotic drugs, risperidone was started and gradually increased to 4 mg/day. The above symptoms were relieved, particularly auditory hallucination and excitement were promptly improved. Persecutory delusion, however persisted, and deteriorated. At one year after the start of this risperidone regimen, he exhibited severe blepharospasm symptoms (increased rate of eye blinking, light sensitivity) and oromandibular symptoms (trismus, jaw pain, dysarthria). He was diagnosed with Meige syndrome. His antipsychotic drug was changed from risperidone to paliperidone. Two months after switching from risperidone to paliperidone, his eye blinking, light sensitivity, jaw pain, and trismus gradually improved, although the dysarthria persisted. Six months after starting paliperidone, his symptoms of Meige syndrome were completely remitted. He has been well without relapse at 12 mg/day of paliperidone. The case suggests that Meige syndrome is relieved by changing from risperidone to paliperidone. The precise mechanism of the relief remains, however, unknown.

Associations between baseline plasma MHPG (3-methoxy-4-hydroxyphenylglycol) levels and clinical responses with respect to milnacipran versus paroxetine treatment

The purpose of this study was to investigate the effects of milnacipran and paroxetine on plasma levels of catecholamine metabolites, and we attempted to elucidate the differences between the mechanisms of these drugs in catecholaminergic neurons. In depressed patients, we investigated the relationships among pretreatment levels of catecholamine metabolites, the changes in plasma catecholamine metabolite levels before and after administration of milnacipran or paroxetine, and clinical response to these drugs. Responders to milnacipran showed lower pretreatment levels of plasma 3-methoxy-4-hydroxyphenylglycol (pMHPG) than did nonresponders to milnacipran; there was also a positive correlation between changes in pMHPG levels and percent improvement of the score on the 17-item Hamilton Rating Scale for Depression (HRSD). On the other hand, responders to paroxetine showed higher pretreatment levels of pMHPG than did nonresponders to paroxetine, and a negative correlation was observed between changes in pMHPG levels and percent improvement of the HRSD score. However, a significant difference was not observed in the pretreatment plasma level of homovanillic acid between responders and nonresponders to treatment with milnacipran or paroxetine. These results suggest that there is an association between baseline pMHPG levels and clinical responses with respect to milnacipran versus paroxetine treatment.