Association Between Serum Neurofilament Light Chain and Neurochemistry Deficits in Patients with Spinocerebellar Ataxia Type 3.

Extensive evidence supports the claim that the serum neurofilament light chain (sNfL) can be used as a biomarker to monitor disease severity in patients with spinocerebellar ataxia type 3 (SCA3). However, little is known about the associations between sNfL levels and neurochemical alterations in SCA3 patients. In this study, we performed a cross-sectional study to analyze the association between sNfL and brain metabolic changes in SCA3 patients. The severity of ataxia was assessed by using the Scale for the Assessment and Rating of Ataxia (SARA) and the International Cooperative Ataxia Rating Scale (ICARS). The sNfL levels and brain metabolic changes, represented by N-acetyl aspartate (NAA)/creatine (Cr) and choline complex (Cho)/Cr ratios, were measured by a single-molecule array and proton magnetic resonance spectroscopy, respectively. In this cohort, we observed consistently elevated sNfL levels and reduced brain metabolites in the cerebellar hemispheres, dentate nucleus, and cerebellar vermis. However, this correlation was further validated in the cerebellar cortex after analysis using pairwise comparisons and a Bonferroni correction. Taken together, our results further confirmed that sNfL levels were increased in SCA3 patients and were negatively correlated with metabolic changes in the cerebellar cortex. Our data also support the idea that sNfL levels are a promising potential complementary biomarker for patients with SCA3.

Evaluation of Relationships between Corticospinal Excitability and Somatosensory Deficits in the Acute and Subacute Phases of Stroke.

BACKGROUND: Somatosensory deficits are common symptoms post stroke. Repetitive transcranial magnetic stimulation (rTMS) over the motor cortex is able to promote motor rehabilitation, whereby its impact on somatosensory functioning remains unknown. This study was designed to evaluate the association between somatosensory deficits and corticospinal excitability following stroke, with the purpose to provide insights on rTMS interventions for the management of somatosensory deficits. METHODS: Somatosensory functioning and corticospinal excitability (motor-evoked potential, MEP; cortical silence period, CSP) were evaluated from a group of sixteen patients with unilateral ischemic stroke in the acute or subacute phase. RESULTS: Results indicated that the uncommon presentation of larger MEPs in ipsilesional vs. contralesional motor cortex was associated with worse somatosensory function compared to those with a smaller MEP in ipsilesional motor cortex. Moreover, increased MEP ratio (ipsilesional vs. contralesional motor cortex) was associated with better somatosensory function in patients with well-preserved somatosensory function. CONCLUSIONS: In well-recovered patients, an increased MEP ratio between the ipsilesional and contralesional motor cortex could be an indicator of improved somatosensory functioning following stroke.

Autonomic dysfunction as the initial presentation in spinocerebellar ataxia type 3: A case report and review of the literature.

Spinocerebellar ataxia type 3 (SCA3), as the most frequent autosomal dominant ataxia worldwide, is characterized by progressive cerebellar ataxia, dysarthria and extrapyramidal signs. Additionally, autonomic dysfunction, as a common clinical symptom, present in the later stage of SCA3. Here, we report a 44-year-old male patient with early feature of autonomic dysfunction includes hyperhidrosis and sexual dysfunction, followed by mild ataxia symptoms. The Unified Multiple System Atrophy Rating Scale (UMSARS) indicated significant dysautonomia during autonomic function testing. Combination of early and autonomic abnormalities and ataxia would be more characteristic of the cerebellar type of multiple system atrophy (MSA-C), the patient's positive family history and identification of an ATXN3 gene mutation supported SCA3 diagnosis. To best of our knowledge, the feature as the initial presentation in SCA3 has not been described. Our study demonstrated that autonomic dysfunction may have occurred during the early stages of SCA3 disease.