Generation of 3 spinocerebellar ataxia type 1 (SCA1) patient-derived induced pluripotent stem cell lines LUMCi002-A, B, and C and 2 unaffected sibling control induced pluripotent stem cell lines LUMCi003-A and B

Spinocerebellar ataxia type 1 (SCA1) is a hereditary neurodegenerative disease caused by a CAG repeat expansion in exon 8 of the ATXN1 gene. We generated induced pluripotent stem cells (hiPSCs) from a SCA1 patient and his non-affected sister by using non-integrating Sendai Viruses (SeV). The resulting hiPSCs are SeVfree, express pluripotency markers, display a normal karyotype, retain the mutation (length of the CAG repeat expansion in the ATXN1 gene) and are able to differentiate into the three germ layers in vitro

Paradoxical effect of baclofen on social behavior in the fragile X syndrome mouse model

Introduction: Fragile X syndrome (FXS) is a common monogenetic cause of intellectual disability, autism spectrum features, and a broad range of other psychiatric and medical problems. FXS is caused by the lack of the fragile X mental retardation protein (FMRP), a translational regulator of specific mRNAs at the postsynaptic compartment. The absence of FMRP leads to aberrant synaptic plasticity, which is believed to be caused by an imbalance in excitatory and inhibitory network functioning of the synapse. Evidence from studies in mice demonstrates that GABA, the major inhibitory neurotransmitter in the brain, and its receptors, is involved in the pathogenesis of FXS. Moreover, several FXS phenotypes, including social behavior deficits, could be corrected in Fmr1 KO mice after acute treatment with GABAB agonists. Methods: As FXS would probably require a lifelong treatment, we investigated the effect of chronic treatment with the GABAB agonist baclofen on social behavior in Fmr1 KO mice on two behavioral paradigms for social behavior: the automated tube test and the three-chamber sociability test. Results: Unexpectedly, chronic baclofen treatment resulted in worsening of the FXS phenotypes in these behavior tests. Strikingly, baclofen treatment also affected wild-type animals in both behavioral tests, inducing a phenotype similar to that of untreated Fmr1 KO mice. Conclusion: Altogether, the disappointing results of recent clinical trials with the R-baclofen enantiomer arbaclofen and our current results indicate that baclofen should be reconsidered and further evaluated before its application in targeted treatment for FXS

Bioenergetics in fibroblasts of patients with Huntington disease are associated with age at onset

Objective We aimed to assess whether differences in energy metabolism in fibroblast cell lines derived from patients with Huntington disease were associated with age at onset independent of the cytosine-adenine-guanine (CAG) repeat number in the mutant allele. Methods For this study, we selected 9 pairs of patients with Huntington disease matched for mutant CAG repeat size and sex, but with a difference of at least 10 years in age at onset, using the Leiden Huntington disease database. From skin biopsies, we isolated fibroblasts in which we (1) quantified the ATP concentration before and after a hydrogen-peroxide challenge and (2) measured mitochondrial respiration and glycolysis in real time, using the Seahorse XF Extracellular Flux Analyzer XF24. Results The ATP concentration in fibroblasts was significantly lower in patients with Huntington disease with an earlier age at onset, independent of calendar age and disease duration. Maximal respiration, spare capacity, and respiration dependent on complex II activity, and indices of mitochondrial respiration were significantly lower in patients with Huntington disease with an earlier age at onset, again independent of calendar age and disease duration. Conclusions A less efficient bioenergetics profile was found in fibroblast cells from patients with Huntington disease with an earlier age at onset independent of mutant CAG repeat size. Thus, differences in bioenergetics could explain part of the residual variation in age at onset in Huntington disease

Generation of genetically matched hiPSC lines from two mosaic facioscapulohumeral dystrophy type 1 patients

Facioscapulohumeral dystrophy type 1 (FSHD1) is caused by contraction of the D4Z4 repeat array on chromosome 4q resulting in sporadic misexpression of the transcription factor DUX4 in skeletal muscle tissue. In ~4% of families, de novo D4Z4 contractions occur after fertilization resulting in somatic mosaicism with control and FSHD1 cell populations present within the same patient. Reprogramming of mosaic fibroblasts from two FSHD1 patients into human induced pluripotent stem cells (hiPSCs) generated genetically matched control and FSHD1 hiPSC lines. All hiPSC lines contained a normal karyotype, expressed pluripotency genes and differentiated into cells from the three germ layers

Generation of 3 human induced pluripotent stem cell lines LUMCi005-A, B and C from a Hereditary Cerebral Hemorrhage with Amyloidosis-Dutch type patient

Hereditary Cerebral Hemorrhage with Amyloidosis-Dutch type (HCHWA-D) is an autosomal dominant hereditary disease caused by a point mutation in exon 17 of the APP gene. We generated human induced pluripotent stem cells (hiPSCs) from a symptomatic HCHWA-D patient by using non-integrating Sendai virus (SeV). The newly generated hiPSCs express all pluripotency markers, have a normal karyotype, carry the Dutch mutation, can differentiate in the three germ layers in vitro and are SeV free

Presence of inclusions positive for polyglycine containing protein, FMRpolyG, indicates that repeat-associated non-AUG translation plays a role in fragile X-associated primary ovarian insufficiency

STUDY QUESTION: Does repeat-associated non-AUG (RAN) translation play a role in fragile X-associated primary ovarian insufficiency (FXPOI), leading to the presence of polyglycine containing protein (FMRpolyG)-positive inclusions in ovarian tissue? SUMMARY ANSWER: Ovaries of a woman with FXPOI and of an Fmr1 premutation (PM) mouse model (exCGG-KI) contain intranuclear inclusions that stain positive for both FMRpolyG and ubiquitin. WHAT IS KNOWN ALREADY: Women who carry the FMR1 PM are at 20-fold increased risk to develop primary ovarian insufficiency (FXPOI). A toxic RNA gain-of-function has been suggested as the underlying mechanism since the PM results in increased levels of mRNA containing an expanded repeat, but reduced protein levels of fragile X mental retardation protein (FMRP). Recently, RAN translation has been shown to occur from FMR1 mRNA that contains PM repeat expansions, leading to FMRpolyG inclusions in brain and non-CNS tissues of fragile X-associated tremor/ataxia syndrome (FXTAS) patients. STUDY DESIGN, SIZE, DURATION: Ovaries of a woman with FXPOI and women without PM (controls), and ovaries from wild-type and exCGG-KI mice were analyzed by immunohistochemistry for the presence of inclusions that stained for ubiquitin and FMRpolyG. The ovaries from wild-type and exCGG-KI mice were further characterized for the number of follicles, Fmr1 mRNA levels and FMRP protein expression. The presence of inclusions was also analyzed in pituitaries of a man with FXTAS and the exCGG-KI mice. PARTICIPANTS/MATERIALS, SETTING, METHODS: Human ovaries from a woman with FXPOI and two control subjects an

Reversibility of neuropathology and motor deficits in an inducible mouse model for FXTAS

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder affecting carriers of the fragile X-premutation, who have an expanded CGG repeat in the 5