Activity-induced MeCP2 phosphorylation regulates retinogeniculate synapse refinement.

Mutations in MECP2 give rise to Rett syndrome (RTT), an X-linked neurodevelopmental disorder that results in broad cognitive impairments in females. While the exact etiology of RTT symptoms remains unknown, one possible explanation for its clinical presentation is that loss of MECP2 causes miswiring of neural circuits due to defects in the brain's capacity to respond to changes in neuronal activity and sensory experience. Here, we show that MeCP2 is phosphorylated at four residues in the mouse brain (S86, S274, T308, and S421) in response to neuronal activity, and we generate a quadruple knock-in (QKI) mouse line in which all four activity-dependent sites are mutated to alanines to prevent phosphorylation. QKI mice do not display overt RTT phenotypes or detectable gene expression changes in two brain regions. However, electrophysiological recordings from the retinogeniculate synapse of QKI mice reveal that while synapse elimination is initially normal at P14, it is significantly compromised at P20. Notably, this phenotype is distinct from the synapse refinement defect previously reported for Mecp2 null mice, where synapses initially refine but then regress after the third postnatal week. We thus propose a model in which activity-induced phosphorylation of MeCP2 is critical for the proper timing of retinogeniculate synapse maturation specifically during the early postnatal period.

Activity-Induced MeCP2 Phosphorylation Regulates Retinogeniculate Synapse Refinement.

Mutations in MECP2 give rise to Rett syndrome (RTT), an X-linked neurodevelopmental disorder that results in broad cognitive impairments in females. While the exact etiology of RTT symptoms remains unknown, one possible explanation for its clinical presentation is that loss of MeCP2 causes miswiring of neural circuits due to defects in the brain's capacity to respond to changes in neuronal activity and sensory experience. Here we show that MeCP2 is phosphorylated at four residues in the brain (S86, S274, T308, and S421) in response to neuronal activity, and we generate a quadruple knock-in (QKI) mouse line in which all four activity-dependent sites are mutated to alanines to prevent phosphorylation. QKI mice do not display overt RTT phenotypes or detectable gene expression changes in two brain regions. However, electrophysiological recordings from the retinogeniculate synapse of QKI mice reveal that while synapse elimination is initially normal at P14, it is significantly compromised at P20. Notably, this phenotype is distinct from that previously reported for Mecp2 null mice, where synapses initially refine but then regress after the third postnatal week. We thus propose a model in which activity-induced phosphorylation of MeCP2 is critical for the proper timing of retinogeniculate synapse maturation specifically during the early postnatal period. SIGNIFICANCE STATEMENT: Rett syndrome (RTT) is an X-linked neurodevelopmental disorder that predominantly affects girls. RTT is caused by loss of function mutations in a single gene MeCP2. Girls with RTT develop normally during their first year of life, but then experience neurological abnormalities including breathing and movement difficulties, loss of speech, and seizures. This study investigates the function of the MeCP2 protein in the brain, and how MeCP2 activity is modulated by sensory experience in early life. Evidence is presented that sensory experience affects MeCP2 function, and that this is required for synaptic pruning in the brain. These findings provide insight into MeCP2 function, and clues as to what goes awry in the brain when the function of MeCP2 is disrupted.

The impact of ocrelizumab on health-related quality of life in individuals with multiple sclerosis.

BACKGROUND: Ocrelizumab is approved for the treatment of both relapsing and progressive multiple sclerosis (MS). OBJECTIVE: To examine the impact of ocrelizumab on health-related quality of life (HRQOL) in individuals with MS. METHODS: Ninety-eight individuals with relapsing and 32 with progressive MS were enrolled. Participants were administered a battery of patient-reported outcome (PRO) measures at their first ocrelizumab infusion, and infusions at 6 and 12 months. PRO measures included the Medical Outcomes Study SF-36 and Neuro-QoL. RESULTS: At baseline, participants had low mean scores across HRQOL domains. After 12 months, increases were observed on SF-36 Role-Physical, General Health, Vitality, Role-Emotional, Mental health and Mental Component Summary. On Neuro-QoL, improvements were seen in Positive Affect, Anxiety, Emotional and Behavioral Dyscontrol and Fatigue. Several demographic and clinical characteristics were associated with HRQOL at baseline. The strongest associations were between physical HRQOL measures and measures of MS disability. Associations between the longitudinal change in HRQOL scores and baseline demographic and clinical characteristics were mild. CONCLUSIONS: We observed significant improvements across multiple mental HRQOL domains at 12 months in individuals treated with ocrelizumab. These findings support the use of HRQOL measures to provide a subjective measure of treatment impact that complements traditional outcomes.

Comparison of health-related quality of life across treatment groups in individuals with multiple sclerosis.

BACKGROUND: Outcome measures typically used to evaluate disease modifying therapies (DMTs) provide important information regarding their effects on disease activity, but they do not capture the full impact of living with multiple sclerosis (MS). Patient reported outcome measures (PROs) are increasingly being used to capture an individual's subjective experience of disease. We compared DMTs across a wide range of PRO outcomes in individuals with MS. METHODS: Subjects enrolled in SysteMS completed the computer adaptive testing version of the Neuro-QoL within four weeks of a clinical neurological exam. Neuro-QoL measures included the following 11 health-related quality of life (HRQOL) domains: Ability to participate in Social Roles and Activities, Anxiety, Cognitive Function, Depression, Emotional and Behavioral Dyscontrol, Fatigue, Lower Extremity Function (mobility), Positive Affect and Wellbeing, Satisfaction with Social Roles and Activities, Stigma, and Upper Extremity Function (fine motor). Treatments were grouped based on the three main modes of delivery: injectable, oral and infusion. The three treatment groups were compared using linear regression adjusting for two sets of covariates (set 1: age, sex, disease duration and EDSS; set 2: age, sex, disease duration, EDSS and treatment duration). We also compared the individual treatments using linear regression. RESULTS: After adjusting for the first set of clinical and demographic features of MS, there was a difference between treatment groups for Upper Extremity Function and Stigma. Subjects using injectable treatments reported better functioning in terms of Upper Extremity Function and Stigma than subjects using infusion treatments. In addition, subjects using injectable treatments reported better Upper Extremity Function than subjects treated with oral DMTs. When all individual treatments were compared, interferon-treated subjects reported significantly better functioning in terms of Stigma than natalizumab treated subjects. When further adjusting for time on treatment, the group differences were attenuated and no longer statistically significant. CONCLUSION: We examined differences between MS treatment groups across a wide range of HRQOL outcomes. The results suggest that overall there are few differences between treatments on the physical, cognitive and emotional dimensions of well-being.