Development of an oral treatment that rescues gait ataxia and retinal degeneration in a phenotypic mouse model of familial dysautonomia.

Familial dysautonomia (FD) is a rare neurodegenerative disease caused by a splicing mutation in elongator acetyltransferase complex subunit 1 (ELP1). This mutation leads to the skipping of exon 20 and a tissue-specific reduction of ELP1, mainly in the central and peripheral nervous systems. FD is a complex neurological disorder accompanied by severe gait ataxia and retinal degeneration. There is currently no effective treatment to restore ELP1 production in individuals with FD, and the disease is ultimately fatal. After identifying kinetin as a small molecule able to correct the ELP1 splicing defect, we worked on its optimization to generate novel splicing modulator compounds (SMCs) that can be used in individuals with FD. Here, we optimize the potency, efficacy, and bio-distribution of second-generation kinetin derivatives to develop an oral treatment for FD that can efficiently pass the blood-brain barrier and correct the ELP1 splicing defect in the nervous system. We demonstrate that the novel compound PTC258 efficiently restores correct ELP1 splicing in mouse tissues, including brain, and most importantly, prevents the progressive neuronal degeneration that is characteristic of FD. Postnatal oral administration of PTC258 to the phenotypic mouse model TgFD9;Elp1Δ20/flox increases full-length ELP1 transcript in a dose-dependent manner and leads to a 2-fold increase in functional ELP1 in the brain. Remarkably, PTC258 treatment improves survival, gait ataxia, and retinal degeneration in the phenotypic FD mice. Our findings highlight the great therapeutic potential of this novel class of small molecules as an oral treatment for FD.

Rescue of a familial dysautonomia mouse model by AAV9-Exon-specific U1 snRNA.

Familial dysautonomia (FD) is a currently untreatable, neurodegenerative disease caused by a splicing mutation (c.2204+6T>C) that causes skipping of exon 20 of the elongator complex protein 1 (ELP1) pre-mRNA. Here, we used adeno-associated virus serotype 9 (AAV9-U1-FD) to deliver an exon-specific U1 (ExSpeU1) small nuclear RNA, designed to cause inclusion of ELP1 exon 20 only in those cells expressing the target pre-mRNA, in a phenotypic mouse model of FD. Postnatal systemic and intracerebral ventricular treatment in these mice increased the inclusion of ELP1 exon 20. This also augmented the production of functional protein in several tissues including brain, dorsal root, and trigeminal ganglia. Crucially, the treatment rescued most of the FD mouse mortality before one month of age (89% vs 52%). There were notable improvements in ataxic gait as well as renal (serum creatinine) and cardiac (ejection fraction) functions. RNA-seq analyses of dorsal root ganglia from treated mice and human cells overexpressing FD-ExSpeU1 revealed only minimal global changes in gene expression and splicing. Overall then, our data prove that AAV9-U1-FD is highly specific and will likely be a safe and effective therapeutic strategy for this debilitating disease.

Tissue- and cell-type-specific molecular and functional signatures of 16p11.2 reciprocal genomic disorder across mouse brain and human neuronal models.

Chromosome 16p11.2 reciprocal genomic disorder, resulting from recurrent copy-number variants (CNVs), involves intellectual disability, autism spectrum disorder (ASD), and schizophrenia, but the responsible mechanisms are not known. To systemically dissect molecular effects, we performed transcriptome profiling of 350 libraries from six tissues (cortex, cerebellum, striatum, liver, brown fat, and white fat) in mouse models harboring CNVs of the syntenic 7qF3 region, as well as cellular, transcriptional, and single-cell analyses in 54 isogenic neural stem cell, induced neuron, and cerebral organoid models of CRISPR-engineered 16p11.2 CNVs. Transcriptome-wide differentially expressed genes were largely tissue-, cell-type-, and dosage-specific, although more effects were shared between deletion and duplication and across tissue than expected by chance. The broadest effects were observed in the cerebellum (2,163 differentially expressed genes), and the greatest enrichments were associated with synaptic pathways in mouse cerebellum and human induced neurons. Pathway and co-expression analyses identified energy and RNA metabolism as shared processes and enrichment for ASD-associated, loss-of-function constraint, and fragile X messenger ribonucleoprotein target gene sets. Intriguingly, reciprocal 16p11.2 dosage changes resulted in consistent decrements in neurite and electrophysiological features, and single-cell profiling of organoids showed reciprocal alterations to the proportions of excitatory and inhibitory GABAergic neurons. Changes both in neuronal ratios and in gene expression in our organoid analyses point most directly to calretinin GABAergic inhibitory neurons and the excitatory/inhibitory balance as targets of disruption that might contribute to changes in neurodevelopmental and cognitive function in 16p11.2 carriers. Collectively, our data indicate the genomic disorder involves disruption of multiple contributing biological processes and that this disruption has relative impacts that are context specific.

Selective retinal ganglion cell loss and optic neuropathy in a humanized mouse model of familial dysautonomia.

Familial dysautonomia (FD) is an autosomal recessive neurodegenerative disease caused by a splicing mutation in the gene encoding Elongator complex protein 1 (ELP1, also known as IKBKAP). This mutation results in tissue-specific skipping of exon 20 with a corresponding reduction of ELP1 protein, predominantly in the central and peripheral nervous system. Although FD patients have a complex neurological phenotype caused by continuous depletion of sensory and autonomic neurons, progressive visual decline leading to blindness is one of the most problematic aspects of the disease, as it severely affects their quality of life. To better understand the disease mechanism as well as to test the in vivo efficacy of targeted therapies for FD, we have recently generated a novel phenotypic mouse model, TgFD9; IkbkapΔ20/flox. This mouse exhibits most of the clinical features of the disease and accurately recapitulates the tissue-specific splicing defect observed in FD patients. Driven by the dire need to develop therapies targeting retinal degeneration in FD, herein, we comprehensively characterized the progression of the retinal phenotype in this mouse, and we demonstrated that it is possible to correct ELP1 splicing defect in the retina using the splicing modulator compound (SMC) BPN-15477.

Evaluating adherence, tolerability and safety of oral calcium citrate in elderly osteopenic subjects: a real-life non-interventional, prospective, multicenter study.

BACKGROUND: Osteoporosis is a common concern in the elderly that leads to fragile bones. Calcium supplementation plays a crucial role in improving bone health, reducing fracture risk, and supporting overall skeletal strength in this vulnerable population. However, there is conflicting evidence on the safety of calcium supplements in elderly individuals. AIM: The aim of this study was to evaluate the adherence, safety and tolerability of calcium citrate supplementation in elderly osteopenic subjects. METHODS: In this non-interventional, prospective, multicenter study, subjects received daily 500 mg calcium citrate supplementation for up to one year. Adherence was calculated based on compliance and persistence. Safety was assessed through adverse reactions (ARs), deaths, and clinical laboratory evaluations. RESULTS: A total of 268 Caucasian subjects (91.4% female, mean age 70 ± 4.5 years) participated in the study. Mean adherence to treatment was 76.6 ± 29.5% and half of subjects had an adherence of 91% and ~ 33% of participants achieved complete (100%) adherence. ARs were reported by nine (3.9%) subjects, primarily gastrointestinal disorders, with no serious ARs. The frequency of all adverse events (including ARs) was significantly higher in subjects with adherence of < 80% (41.6%; 32/77) vs. those with adherence ≥ 80% (11%; 16/145, p < 0.0001). Both systolic and diastolic blood pressure decreased from baseline to follow-up visit (change of -2.8 ± 13.9 mmHg, p = 0.0102 and -2.1 ± 10.4 mmHg, p = 0.0116, respectively). CONCLUSION: This study demonstrated favorable adherence to calcium citrate supplementation in elderly osteopenic subjects. The occurrence of ARs, though generally mild, were associated with lower adherence to calcium supplementation.

Sexual Dysfunctions in Females with Parkinson's Disease: A Cross-Sectional Study with a Psycho-Endocrinological Perspective.

Background and Objectives: Normal human sexual functioning is a complex integration of an intact neuroanatomic substrate, vascular supply, a balanced hormonal profile, and a predominance of excitatory over inhibitory psychological mechanisms. However, sexual functioning in Parkinson's disease (PD) is often overlooked in clinical practice, especially in female patients. Materials and Methods: In this cross-sectional study, we have investigated the frequency of sexual dysfunction and the possible correlation with psycho-endocrinological factors in a sample of women with idiopathic PD. Patients were assessed using a semi-structured sexual interview, in addition to psychometric tools, including the Hamilton Rating Scale for Anxiety and for Depression and the Coping Orientation to the Problems Experiences-New Italian Version. Specific blood tests, including testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), estrogen E2, prolactin (PRL), and vitamin D3 were also evaluated. Results: Our results reported a statistical difference in sexual intercourse frequency before and after the onset of PD (p < 0.001). The percentage of women who complained about reduced sexual desire increased after diagnosis (52.7%) compared to the period before the onset of the illness (36.8%). The endocrinological profile in females with PD revealed statistically significant differences regarding testosterone (p < 0.0006), estradiol (p < 0.00), vitamin D3 (p < 0.006), and calcium (0.002). Depression (44% characterized by perceived feelings of anger and frustration during sexual intercourse) and anxiety symptoms (29.5% reported feelings of fear and anxiety for not satisfying the partner) with abnormal coping strategies (48.14% experienced feelings of anger and intolerance) were also found to be statistically significant. This study showed a high frequency of sexual dysfunction in female patients with PD, which correlated with sexual hormone abnormalities, mood/anxiety, and coping strategies alterations. This supports the idea that there is a need to better investigate the sexual function of female patients with PD to provide them with an adequate therapeutic approach and potentially improve quality of life.

ELP1 Splicing Correction Reverses Proprioceptive Sensory Loss in Familial Dysautonomia.

Familial dysautonomia (FD) is a recessive neurodegenerative disease caused by a splice mutation in Elongator complex protein 1 (ELP1, also known as IKBKAP); this mutation leads to variable skipping of exon 20 and to a drastic reduction of ELP1 in the nervous system. Clinically, many of the debilitating aspects of the disease are related to a progressive loss of proprioception; this loss leads to severe gait ataxia, spinal deformities, and respiratory insufficiency due to neuromuscular incoordination. There is currently no effective treatment for FD, and the disease is ultimately fatal. The development of a drug that targets the underlying molecular defect provides hope that the drastic peripheral neurodegeneration characteristic of FD can be halted. We demonstrate herein that the FD mouse TgFD9;IkbkapΔ20/flox recapitulates the proprioceptive impairment observed in individuals with FD, and we provide the in vivo evidence that postnatal correction, promoted by the small molecule kinetin, of the mutant ELP1 splicing can rescue neurological phenotypes in FD. Daily administration of kinetin starting at birth improves sensory-motor coordination and prevents the onset of spinal abnormalities by stopping the loss of proprioceptive neurons. These phenotypic improvements correlate with increased amounts of full-length ELP1 mRNA and protein in multiple tissues, including in the peripheral nervous system (PNS). Our results show that postnatal correction of the underlying ELP1 splicing defect can rescue devastating disease phenotypes and is therefore a viable therapeutic approach for persons with FD.

Effects of COVID-19 in Endocrine Patients: A Cross-Sectional Study.

Introduction: Home confinement due to COVID-19 lockdown led to changes in daily routines, including social interactions, as well as restrictions on the possibility of playing sports and eating habits. These changes could have a greater impact on patients suffering from chronic diseases, such as endocrine patients, especially in emotional and behavioral dimensions. Materials and Methods: This study aimed to assess the effects of COVID-19-induced quarantine on daily habits in a group of patients with endocrine disorders, focusing on food consumption, eating habits and sleep during the confinement. Eighty-five endocrine patients were enrolled. A structured interview was administered to investigate socio-demographic information, general medical conditions, and habits adopted during quarantine. All patients underwent the Spielberger State Anxiety Inventory (STAI-Y1) to assess state anxiety. Result: Results showed that subjects mainly had a sedentary lifestyle. We found a significant increase in the number of cigarettes in smokers and in meals consumed during confinement, as well as a high rate of sleep disturbance, especially insomnia. Notably, physical well-being resulted to be a predictive factor (OR = 0.38; 95%CI = [0.95,0.66]), whereas anxiety was a risk factor for sleep disorder (OR = 1.22; 95%CI = [1.10,1.40]), as was working in public and private offices and being a student. Conclusions: Changes in daily habits were likely due to the alterations in routine, resulting in greater boredom and inactivity during the day. In addition, future research should focus on the importance of patient adherence to therapy.

Exon-specific U1 snRNAs improve ELP1 exon 20 definition and rescue ELP1 protein expression in a familial dysautonomia mouse model.

Familial dysautonomia (FD) is a rare genetic disease with no treatment, caused by an intronic point mutation (c.2204+6T>C) that negatively affects the definition of exon 20 in the elongator complex protein 1 gene (ELP1 also known as IKBKAP). This substitution modifies the 5' splice site and, in combination with regulatory splicing factors, induces different levels of exon 20 skipping, in various tissues. Here, we evaluated the therapeutic potential of a novel class of U1 snRNA molecules, exon-specific U1s (ExSpeU1s), in correcting ELP1 exon 20 recognition. Lentivirus-mediated expression of ELP1-ExSpeU1 in FD fibroblasts improved ELP1 splicing and protein levels. We next focused on a transgenic mouse model that recapitulates the same tissue-specific mis-splicing seen in FD patients. Intraperitoneal delivery of ELP1-ExSpeU1s-adeno-associated virus particles successfully increased the production of full-length human ELP1 transcript and protein. This splice-switching class of molecules is the first to specifically correct the ELP1 exon 20 splicing defect. Our data provide proof of principle of ExSpeU1s-adeno-associated virus particles as a novel therapeutic strategy for FD.

Sexual Dysfunction in Parkinson Disease: A Multicenter Italian Cross-sectional Study on a Still Overlooked Problem.

BACKGROUND: Prevalence rates of sexual dysfunction (SD) in Parkinson's disease (PD) are likely to be underestimated and their etiology is still unknown. More understanding of this issue is needed. AIM: To investigate prevalence of SD and its variables, including gender differences, in a sample of PD patients. METHODS: This multicenter observational study included 203 patients (113 males and 90 females) affected by PD (diagnosed according to UK Parkinson's Disease Society Brain Bank clinical diagnostic criteria 28), and living in 3 different Italian regions. Patients were evaluated using a semi-structured interview (a 40-item ad hoc questionnaire, developed by the authors to investigate patient's 3 main life areas: sociodemographic information, illness perception, and sexuality) and specific standardized scales to investigate SD, as well as by means of tools to assess their motor impairment, daily life activities, and disease-related caregiver burden (CBI). MAIN OUTCOME MEASURES: The International Index of Erectile Function and the Female Sexual Function Index. RESULTS: Sexual dysfunction was observed in about 68% of men, and in around 53% of women loss of libido being the main sexual concern in both sexes. Men were significantly more affected by SD than women (χ2 (1) = 4.34, P-value = .037), but no difference in the severity of the dysfunction emerged between genders. Around 85% of PD patients had a stable couple relationship, and about 40% were satisfied with such a relationship. However, about 57% of the patients stated that the disease affected their sexual life, especially due to reduced sexual desire, and the frequency of sexual intercourses. Moreover, significant differences between subjects with SD and subjects without SD were found in UPDRS (I-II-III domains), in Hamilton Depression Rating Scale and CBI scores. CLINICAL IMPLICATIONS: Clinicians dealing with PD should pay more attention to sexual issues, as discussing and treating sexual problems enters the framework of a holistic approach, which is mandatory in chronic illness. STRENGTHS & LIMITATIONS: The major strengths of this study include the multicenter nature of the study, to overcome single-center methodological bias. The main limitation is the relatively small sample size, and the absence of a control group, even if there are growing literature data on sexuality and aging supporting our findings. CONCLUSION: SD is a highly prevalent and devastating problem in patients affected by PD, negatively affecting their quality of life. Raciti L, De Cola MC, Ortelli P, et al. Sexual Dysfunction in Parkinson Disease: A Multicenter Italian Cross-sectional Study on a Still Overlooked Problem. J Sex Med 2020;17:1914-1925.

Sensory and autonomic deficits in a new humanized mouse model of familial dysautonomia.

Familial dysautonomia (FD) is an autosomal recessive neurodegenerative disease that affects the development and survival of sensory and autonomic neurons. FD is caused by an mRNA splicing mutation in intron 20 of the IKBKAP gene that results in a tissue-specific skipping of exon 20 and a corresponding reduction of the inhibitor of kappaB kinase complex-associated protein (IKAP), also known as Elongator complex protein 1. To date, several promising therapeutic candidates for FD have been identified that target the underlying mRNA splicing defect, and increase functional IKAP protein. Despite these remarkable advances in drug discovery for FD, we lacked a phenotypic mouse model in which we could manipulate IKBKAP mRNA splicing to evaluate potential efficacy. We have, therefore, engineered a new mouse model that, for the first time, will permit to evaluate the phenotypic effects of splicing modulators and provide a crucial platform for preclinical testing of new therapies. This new mouse model, TgFD9; Ikbkap(Δ20/flox) was created by introducing the complete human IKBKAP transgene with the major FD splice mutation (TgFD9) into a mouse that expresses extremely low levels of endogenous Ikbkap (Ikbkap(Δ20/flox)). The TgFD9; Ikbkap(Δ20/flox) mouse recapitulates many phenotypic features of the human disease, including reduced growth rate, reduced number of fungiform papillae, spinal abnormalities, and sensory and sympathetic impairments, and recreates the same tissue-specific mis-splicing defect seen in FD patients. This is the first mouse model that can be used to evaluate in vivo the therapeutic effect of increasing IKAP levels by correcting the underlying FD splicing defect.

Denosumab Inhibition of RANKL and Insulin Resistance in Postmenopausal Women with Osteoporosis.

The tumor necrosis factor-related cytokine receptor activator of nuclear factor kappa B ligand (RANKL) has been proposed as predictor of incident type 2 diabetes mellitus, and experimental blockade of RANKL resulted in a marked improvement of glucose tolerance. Denosumab is a fully human monoclonal antibody that binds to RANKL and prevents osteoclast formation, function and survival, leading to fracture risk reduction. The aim of our study was to investigate glucometabolic parameters, insulin resistance, and lipid profile in non-diabetic women receiving denosumab. Forty-eight women with postmenopausal osteoporosis were enrolled and treated with a subcutaneous dose (60 mg) of denosumab. At baseline and after 4, 12, ad 24 weeks, insulin resistance was computed by homeostasis model assessment of insulin resistance (HOMA-IR) and total cholesterol, triglycerides and HDL cholesterol were also measured. At baseline and after 24 weeks, bone turn-over markers were also evaluated. After denosumab administration, with the exception of a slight reduction of insulin and HOMA-IR values after 4 weeks (p < 0.05), neither fasting plasma glucose nor insulin and insulin resistance were significantly changed. Lipid parameters remained unchanged at each time-points of this study. A reduction of C-telopeptide of type 1 collagen (-63%, p < 0.0001) and osteocalcin (-45%, p < 0.0001), as bone resorption and formation markers, respectively, were observed after 24 weeks. Baseline levels of bone biomarkers were not predictive of HOMA-IR, and changes of osteocalcin were not associated to markers of glucose control. In osteoporotic otherwise healthy postmenopausal women, denosumab was not associated with relevant modification of insulin resistance and lipid profile.

Effects of strontium ranelate on bone mass and bone turnover in women with thalassemia major-related osteoporosis.

Subjects affected by thalassemia major (TM) often have reduced bone mass and increased fracture risk. Strontium ranelate (SrR) is an effective treatment for postmenopausal and male osteoporosis. To date, no data exist on the use of SrR in the treatment of TM-related osteoporosis. Our aim was to evaluate the effects of SrR on bone mineral density (BMD), bone turnover markers and inhibitors of Wnt signaling (sclerostin and DKK-1). Twenty-four TM osteoporotic women were randomized to receive daily SrR 2 g or placebo in addition to calcium carbonate (1,000 mg) and vitamin D (800 IU). BMD at the lumbar spine and femoral neck, bone turnover markers (C-terminal telopeptide of procollagen type I [CTX], bone-specific alkaline phosphatase [BSAP]) and insulin-like growth factor-1 (IGF-1), sclerostin and DKK-1 were assessed at baseline and after 24 months. Back pain was measured by visual analog scale (VAS) every 6 months. After 24 months, TM women treated with SrR had increased their spine BMD values in comparison to baseline (p < 0.05). Moreover, they also exhibited a reduction of CTX and sclerostin levels (but not DKK-1) and exhibited an increase of BSAP and IGF-1 (p < 0.05); however, no significant changes were observed in the placebo group. In the SrR group, a reduction of back pain was observed after 18 months in comparison to baseline (p < 0.05) and after 24 months in comparison to placebo (p < 0.05). Our study reports for the first time the effects of SrR in the treatment of TM-related osteoporosis. SrR treatment improved BMD and normalized bone turnover markers, as well as lowering sclerostin serum levels.

Altered Tnnt3 characterizes selective weakness of fast fibers in mice overexpressing FSHD region gene 1 (FRG1).

Facioscapulohumeral muscular dystrophy (FSHD), a common hereditary myopathy, is characterized by atrophy and weakness of selective muscle groups. FSHD is considered an autosomal dominant disease with incomplete penetrance and unpredictable variability of clinical expression within families. Mice overexpressing FRG1 (FSHD region gene 1), a candidate gene for this disease, develop a progressive myopathy with features of the human disorder. Here, we show that in FRG1-overexpressing mice, fast muscles, which are the most affected by the dystrophic process, display anomalous fast skeletal troponin T (fTnT) isoform, resulting from the aberrant splicing of the Tnnt3 mRNA that precedes the appearance of dystrophic signs. We determine that muscles of FRG1 mice develop less strength due to impaired contractile properties of fast-twitch fibers associated with an anomalous MyHC-actin ratio and a reduced sensitivity to Ca(2+). We demonstrate that the decrease of Ca(2+) sensitivity of fast-twitch fibers depends on the anomalous troponin complex and can be rescued by the substitution with the wild-type proteins. Finally, we find that the presence of aberrant splicing isoforms of TNNT3 characterizes dystrophic muscles in FSHD patients. Collectively, our results suggest that anomalous TNNT3 profile correlates with the muscle impairment in both humans and mice. On the basis of these results, we propose that aberrant fTnT represents a biological marker of muscle phenotype severity and disease progression.

Towards a Deeper Understanding: Utilizing Machine Learning to Investigate the Association between Obesity and Cognitive Decline-A Systematic Review.

Background/Objectives: Several studies have shown a relation between obesity and cognitive decline, highlighting a significant global health challenge. In recent years, artificial intelligence (AI) and machine learning (ML) have been integrated into clinical practice for analyzing datasets to identify new risk factors, build predictive models, and develop personalized interventions, thereby providing useful information to healthcare professionals. This systematic review aims to evaluate the potential of AI and ML techniques in addressing the relationship between obesity, its associated health consequences, and cognitive decline. Methods: Systematic searches were performed in PubMed, Cochrane, Web of Science, Scopus, Embase, and PsycInfo databases, which yielded eight studies. After reading the full text of the selected studies and applying predefined inclusion criteria, eight studies were included based on pertinence and relevance to the topic. Results: The findings underscore the utility of AI and ML in assessing risk and predicting cognitive decline in obese patients. Furthermore, these new technology models identified key risk factors and predictive biomarkers, paving the way for tailored prevention strategies and treatment plans. Conclusions: The early detection, prevention, and personalized interventions facilitated by these technologies can significantly reduce costs and time. Future research should assess ethical considerations, data privacy, and equitable access for all.

Transcriptome analysis in a humanized mouse model of familial dysautonomia reveals tissue-specific gene expression disruption in the peripheral nervous system.

Familial dysautonomia (FD) is a rare recessive neurodevelopmental disease caused by a splice mutation in the Elongator acetyltransferase complex subunit 1 (ELP1) gene. This mutation results in a tissue-specific reduction of ELP1 protein, with the lowest levels in the central and peripheral nervous systems (CNS and PNS, respectively). FD patients exhibit complex neurological phenotypes due to the loss of sensory and autonomic neurons. Disease symptoms include decreased pain and temperature perception, impaired or absent myotatic reflexes, proprioceptive ataxia, and progressive retinal degeneration. While the involvement of the PNS in FD pathogenesis has been clearly recognized, the underlying mechanisms responsible for the preferential neuronal loss remain unknown. In this study, we aimed to elucidate the molecular mechanisms underlying FD by conducting a comprehensive transcriptome analysis of neuronal tissues from the phenotypic mouse model TgFD9; Elp1Δ20/flox. This mouse recapitulates the same tissue-specific ELP1 mis-splicing observed in patients while modeling many of the disease manifestations. Comparison of FD and control transcriptomes from dorsal root ganglion (DRG), trigeminal ganglion (TG), medulla (MED), cortex, and spinal cord (SC) showed significantly more differentially expressed genes (DEGs) in the PNS than the CNS. We then identified genes that were tightly co-expressed and functionally dependent on the level of full-length ELP1 transcript. These genes, defined as ELP1 dose-responsive genes, were combined with the DEGs to generate tissue-specific dysregulated FD signature genes and networks. Within the PNS networks, we observed direct connections between Elp1 and genes involved in tRNA synthesis and genes related to amine metabolism and synaptic signaling. Importantly, transcriptomic dysregulation in PNS tissues exhibited enrichment for neuronal subtype markers associated with peptidergic nociceptors and myelinated sensory neurons, which are known to be affected in FD. In summary, this study has identified critical tissue-specific gene networks underlying the etiology of FD and provides new insights into the molecular basis of the disease.

Splice modulators target PMS1 to reduce somatic expansion of the Huntington's disease-associated CAG repeat.

Huntington's disease (HD) is a dominant neurological disorder caused by an expanded HTT exon 1 CAG repeat that lengthens huntingtin's polyglutamine tract. Lowering mutant huntingtin has been proposed for treating HD, but genetic modifiers implicate somatic CAG repeat expansion as the driver of onset. We find that branaplam and risdiplam, small molecule splice modulators that lower huntingtin by promoting HTT pseudoexon inclusion, also decrease expansion of an unstable HTT exon 1 CAG repeat in an engineered cell model. Targeted CRISPR-Cas9 editing shows this effect is not due to huntingtin lowering, pointing instead to pseudoexon inclusion in PMS1. Homozygous but not heterozygous inactivation of PMS1 also reduces CAG repeat expansion, supporting PMS1 as a genetic modifier of HD and a potential target for therapeutic intervention. Although splice modulation provides one strategy, genome-wide transcriptomics also emphasize consideration of cell-type specific effects and polymorphic variation at both target and off-target sites.

Bone Health Status in Individuals with Amyotrophic Lateral Sclerosis: A Cross-Sectional Study on the Role of the Trabecular Bone Score and Its Implications in Neurorehabilitation.

Background and Objectives: Osteoporosis is a metabolic skeletal disease resulting in low bone mass with increased bone fragility and susceptibility to fractures. May lead to rapid loss of bone mineral density (BMD) due to physical inactivity and reduced muscle contractions. Generally, the diagnosis of osteoporosis is made using dual X-ray absorptiometry (DXA), by measuring BMD and the trabecular bone score (TBS), which can be useful for detecting bone fragility and susceptibility to fractures. Therefore, the aim of this study was to investigate, using BMD and TBS, the bone health status in a sample of amyotrophic lateral sclerosis (ALS) inpatients attending neurorehabilitation. Materials and Methods: Thirty-nine patients were included in the study and underwent electrocardiogram and blood tests, including calcium and parathyroid hormone, as well as vitamin D dosage, and DXA. Results: We found that the TBS of patients with osteoporosis was lower than that of those ALS patients with osteopenia or normal bone status, both in the lumbar spine and femoral neck, although no statistical significance was reached. In addition, Spearman's correlation coefficient indicated a moderate correlation between TBS and lumbar spine BMD (r = -0.34) and a mild correlation between TBS and femoral neck BMD (r = -0.28). Conclusions: This study confirmed the hypothesis that ALS patients may exhibit deteriorated bone health with lower bone density and focused on the possible role of the TBS in the multidisciplinary approach to ALS.

Reduction of retinal ganglion cell death in mouse models of familial dysautonomia using AAV-mediated gene therapy and splicing modulators.

Familial dysautonomia (FD) is a rare neurodevelopmental and neurodegenerative disease caused by a splicing mutation in the Elongator Acetyltransferase Complex Subunit 1 (ELP1) gene. The reduction in ELP1 mRNA and protein leads to the death of retinal ganglion cells (RGCs) and visual impairment in all FD patients. Currently patient symptoms are managed, but there is no treatment for the disease. We sought to test the hypothesis that restoring levels of Elp1 would thwart the death of RGCs in FD. To this end, we tested the effectiveness of two therapeutic strategies for rescuing RGCs. Here we provide proof-of-concept data that gene replacement therapy and small molecule splicing modifiers effectively reduce the death of RGCs in mouse models for FD and provide pre-clinical foundational data for translation to FD patients.