Alternative splicing of exon 10 in the tau gene as a target for treatment of tauopathies

Tau aggregation is one of the major features in Alzheimer's disease and in several other tauopathies, including frontotemporal dementia with Parkinsonism linked to chromosome 17 (FTDP-17), and progressive supranuclear palsy (PSP). More than 35 mutations in the tau gene have been identified from FTDP-17 patients. A group of these mutations alters splicing of exon 10, resulting in an increase in exon 10 inclusion into tau mRNA. Abnormal splicing with inclusion of exon 10 into tau mRNA has also been observed in PSP and AD patients. These results indicate that abnormal splicing of exon 10, leading to the production of tau with exon 10, is probably one of the mechanisms by which tau accumulates and aggregates in tauopathic brains. Therefore, modulation of exon 10 splicing in the tau gene could potentially be targeted to prevent tauopathies. To identify small molecules or compounds that could potentially be developed into drugs to treat tauopathies, we established a cell-based high-throughput screening assay. In this review, we will discuss how realistic, specific biological molecules can be found to regulate exon 10 splicing in the tau gene for potential treatment of tauopathies

Demencia frontotemporal no familiar y epilepsia generalizada Frontotemporal dementia non familial and generalized epilepsy

Se presenta un paciente de 62 años, sin antecedentes familiares de demencia, que a los 45 años debuta con crisis súbitas de disnea, visión borrosa, caída al suelo y movimientos repetitivos de brazos. Tratado por epilepsia con fenitoína y ácido valproico, repite esporádicamente crisis semejantes. Hace 4 años sus familiares notan cambios de personalidad, irritabilidad y conductas obsesivas. Hace 2 años aparecen episodios de desorientación de días de duración, algunos con alucinaciones auditivas y también fenómenos convulsivos. Ultimamente presenta crisis polimorfas, algunas con prolongada alteración de conciencia, estados catatoniformes y relajación esfinteriana. Examen físico y neurológico sin anormalidades. Evaluación neuropsicológica evidenció consistentes defectos en funciones frontales. EEG mostraron lentitud generalizada y actividad irritativa esporádica en regiones frontotemporales. Atrofia cortical de predominio anterior en CT scan e hipoperfusión fronto-temporal bilateral en SPECT. Exámenes de laboratorio y LCR normales. CONCLUSIÓN: La asociación de DFT con epilepsia, en forma no familiar, sugiere un síndrome neurodegenerativo cortical diferente.<br>A 62 year-old patient is presented, without family antecedents of dementia who begins with 45 years of age with sudden crisis of dyspnea, blurred vision, fall to the floor and repetitive jerks of arms. Tried by epilepsy with phenytoin and valproate repeats similar crisis sporadically. Four years ago their relatives began to notice changes of personality, irritability and obsessive behaviors. Later on, are added episodes of disorientation of days of duration, some with auditory hallucinations and also convulsive manifestations. Finally appear polymorphic crisis, some with continue alteration of consciousness, catatonic states and sphincteric incontinence. Physical and neurological examination without abnormalities. Neuropsychological evaluation evidenced consistent defects in frontal functions. EEG showed widespread slowness and sporadic irritative activity in frontotemporal regions. Anterior cortical atrophy in CTscan and bilateral frontotemporal hypoperfusion in SPECT. Labs exams and CSF were normal. CONCLUSION: The association of FTD and epilepsy, in non-family form, suggests a different neurodegenerative cortical syndrome