Axonal degeneration is a critical, early event in many acute and chronic neurological disorders. It has been consistently observed after traumatic brain injury, but whether axon degeneration is a driver of traumatic brain injury remains unclear. Molecular pathways underlying the pathology of traumatic brain injury have not been defined, and there is no efficacious treatment for traumatic brain injury. Here we show that mice lacking the mouse Toll receptor adaptor Sarm1 (sterile α/Armadillo/Toll-Interleukin receptor homology domain protein) gene, a key mediator of Wallerian degeneration, demonstrate multiple improved traumatic brain injury-associated phenotypes after injury in a closed-head mild traumatic brain injury model. Sarm1(-/-) mice developed fewer β-amyloid precursor protein aggregates in axons of the corpus callosum after traumatic brain injury as compared to Sarm1(+/+) mice. Furthermore, mice lacking Sarm1 had reduced plasma concentrations of the phophorylated axonal neurofilament subunit H, indicating that axonal integrity is maintained after traumatic brain injury. Strikingly, whereas wild-type mice exibited a number of behavioural deficits after traumatic brain injury, we observed a strong, early preservation of neurological function in Sarm1(-/-) animals. Finally, using in vivo proton magnetic resonance spectroscopy we found tissue signatures consistent with substantially preserved neuronal energy metabolism in Sarm1(-/-) mice compared to controls immediately following traumatic brain injury. Our results indicate that the SARM1-mediated prodegenerative pathway promotes pathogenesis in traumatic brain injury and suggest that anti-SARM1 therapeutics are a viable approach for preserving neurological function after traumatic brain injury.

Postpartum depression (PPD) affects up to 1 in 8 women. The early postpartum period is characterized by a downward physiological shift from relatively elevated levels of sex steroids during pregnancy to diminished levels after parturition. Sex steroids influence functional brain connectivity in healthy non-puerperal subjects. This study tests the hypothesis that PPD is associated with attenuation of resting-state functional connectivity (rs-fc) within corticolimbic regions implicated in depression and alterations in neuroactive steroid concentrations as compared to healthy postpartum women. Subjects (n=32) were prospectively evaluated during pregnancy and in the postpartum with repeated plasma neuroactive steroid measurements and mood and psychosocial assessments. Healthy comparison subjects (HCS) and medication-free subjects with unipolar PPD (PPD) were examined using functional magnetic resonance imaging (fMRI) within 9 weeks of delivery. We performed rs-fc analysis with seeds placed in the anterior cingulate cortex (ACC), and bilateral amygdalae (AMYG), hippocampi (HIPP) and dorsolateral prefrontal cortices (DLPFC). Postpartum rs-fc and perinatal neuroactive steroid plasma concentrations, quantified by liquid chromatography/mass spectrometry, were compared between groups. PPD subjects showed attenuation of connectivity for each of the tested regions (i.e. ACC, AMYG, HIPP and DLPFC) and between corticocortical and corticolimbic regions vs. HCS. Perinatal concentrations of pregnanolone, allopregnanolone and pregnenolone were not different between groups. This is the first report of a disruption in the rs-fc patterns in medication-free subjects with PPD. This disruption may contribute to the development of PPD, at a time of falling neuroactive steroid concentrations.

Canavan's disease (CD) is a fatal pediatric leukodystrophy caused by mutations in aspartoacylase (AspA) gene. Currently, there is no effective treatment for CD; however, gene therapy is an attractive approach to ameliorate the disease. Here, we studied progressive neuropathology and gene therapy in short-lived (≤ 1 month) AspA(-/-) mice, a bona-fide animal model for the severest form of CD. Single intravenous (IV) injections of several primate-derived recombinant adeno-associated viruses (rAAVs) as late as postnatal day 20 (P20) completely rescued their early lethality and alleviated the major disease symptoms, extending survival in P0-injected rAAV9 and rAAVrh8 groups to as long as 2 years thus far. We successfully used microRNA (miRNA)-mediated post-transcriptional detargeting for the first time to restrict therapeutic rAAV expression in the central nervous system (CNS) and minimize potentially deleterious effects of transgene overexpression in peripheral tissues. rAAV treatment globally improved CNS myelination, although some abnormalities persisted in the content and distribution of myelin-specific and -enriched lipids. We demonstrate that systemically delivered and CNS-restricted rAAVs can serve as efficacious and sustained gene therapeutics in a model of a severe neurodegenerative disorder even when administered as late as P20.

These data suggest an imbalance between glutamatergic neurotransmission and GABA-ergic neurotransmission in ASD. Higher Gln levels and lower GABA/Cre levels were associated with lower IQ and greater impairments in social cognition across groups.

Purpose: Primary analysis of VISION showed tepotinib had durable clinical activity in patients with MET exon 14 (METex14) skipping non–small cell lung cancer (NSCLC). We present updated outcomes for clinically relevant subgroups. Patients and Methods: This phase II, open-label, multi-cohort study of 500 mg (450 mg active moiety) tepotinib in patients with METex14 skipping NSCLC assessed efficacy and safety in predefined subgroups according to age, prior therapies (chemotherapy and immune checkpoint inhibitors), and brain metastases. An ad hoc retrospective analysis using Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria assessed intracranial activity. Results: 152 patients were evaluable for efficacy (median age: 73.1). Overall, objective response rate (ORR) was 44.7% [95% confidence interval (CI): 36.7–53.0]. Patients aged <75 (n = 84) and ≥75 (n = 68) had ORRs of 48.8% (95% CI: 37.7–60.0) and 39.7% (95% CI: 28.0–52.3), respectively. Treatment-naïve (n = 69) versus previously treated (n = 83) patients showed consistent efficacy [ORR (95% CI): 44.9% (32.9–57.4) vs. 44.6% (33.7–55.9); median duration of response (95% CI): 10.8 (6.9–not estimable) vs. 11.1 (9.5–18.5) months]. Of 15 patients analyzed by RANO-BM (12 received prior radiotherapy), 13 achieved intracranial disease control; 5 of 7 patients with measurable brain metastases had partial intracranial responses. Of 255 patients evaluable for safety, 64 (25.1%) experienced grade ≥3 treatment-related adverse events (TRAE), leading to discontinuation in 27 patients (10.6%). Rates of adverse events (AE) were broadly consistent irrespective of prior therapies. Conclusions: Tepotinib showed meaningful activity across subgroups by age, prior therapies, and brain metastases, with a manageable safety profile and few treatment discontinuations. See related commentary by Rosner and Spira, p. 1055