No abstract

In Huntington's disease (HD), the main clinical symptoms include depression, apathy, cognitive deficits, motor deficiencies and involuntary movements. Cognitive, mood and behavioral changes may precede motor symptoms by up to 15 years. The treatment of these diverse symptoms is challenging. Tetrabenazine and deutetrabenazine are the only medications specifically approved for Huntington's chorea, but they do not affect the non-motor symptoms. For these, antidepressants, antipsychotics, and benzodiazepines have demonstrated benefit in some cases and can be used off-label. These drugs, due to sedative side effects, may negatively influence cognition. Sixteen patients having HD received a 12-week off-label cariprazine (CAR) treatment (1.5–3 mg/day). Cognitive performance and behavioral changes were measured by the Addenbrooke Cognitive Examination (ACE) test, the Cognitive and Behavioral part of the Unified Huntington's Disease Rating Scale (UHDRS), and the Beck Depression Inventory (BDI). Mixed model for repeated measures was fitted to the data, with terms of visit, baseline (BL) and their interaction. Cariprazine treatment resulted in the following changes from BL to week 12, respectively: the mean score of BDI decreased from 17.7 ± 10.7 to 10.0 ± 10.7 (p <0.0097), while the Behavioral Assessment score of the UHDRS decreased from 54.9 ± 11.3 to 32.5 ± 15.4 (p < 0.0001); ACE score increased from 75.1 ± 11.0 to 89.0 ± 9.3 (p < 0.0001); Cognitive Verbal Fluency score from 6.2 ± 2.5 to 7.7 ± 2.7 (p < 0.0103); Symbol Digit Test from 9.2 ± 6.9 to 12.3 ± 8.9 (p < 0.0009). Mild akathisia was the most frequent side effect, presenting in 2 out of 16 patients (12.5%). We conclude that CAR had a positive effect on depressive mood, apathy and cognitive functions in patients with early stage of HD. Based on the neurobiological basis of these symptoms, CAR can improve the dopamine imbalance of the prefrontal cortex. This draws attention to the transdiagnostic approach which supports the further understanding of the similar symptomatology of different neuropsychiatric disorders and helps to identify new indications of pharmaceutical compounds.

Pompe disease is caused by the accumulation of glycogen in the lysosomes due to a deficiency of the lysosomal acid-α-glucosidase (GAA) enzyme. Depending on residual enzyme activity, the disease manifests two distinct phenotypes. In this study, we assess an enzymatic and genetic analysis of Hungarian patients with Pompe disease. Twenty-four patients diagnosed with Pompe disease were included. Enzyme activity of acid-α-glucosidase was measured by mass spectrometry. Sanger sequencing and an MLPA of the GAA gene were performed in all patients. Twenty (83.33%) patients were classified as having late-onset Pompe disease and four (16.66%) had infantile-onset Pompe disease. Fifteen different pathogenic GAA variants were detected. The most common finding was the c.-32-13 T > G splice site alteration. Comparing the α-glucosidase enzyme activity of homozygous cases to the compound heterozygous cases of the c.-32-13 T > G disease-causing variant, the mean GAA activity in homozygous cases was significantly higher. The lowest enzyme activity was found in cases where the c.-32-13 T > G variant was not present. The localization of the identified sequence variations in regions encoding the crucial protein domains of GAA correlates with severe effects on enzyme activity. A better understanding of the impact of pathogenic gene variations may help earlier initiation of enzyme replacement therapy (ERT) if subtle symptoms occur. Further information on the effect of GAA gene variation on the efficacy of treatment and the extent of immune response to ERT would be of importance for optimal disease management and designing effective treatment plans.