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Glioblastoma, a formidable brain tumor characterized by dysregulated NAD metabolism, poses a significant therapeutic challenge. The NAMPT inhibitor FK866, which induces NAD depletion, has shown promise in controlling tumor proliferation and modifying the tumor microenvironment. However, the clinical efficacy of FK866 as a single drug therapy for glioma is limited. In this study, we aim to disrupt NAD metabolism using fluorinated NAD precursors and explore their synergistic effect with FK866 in inducing cytotoxicity in glioblastoma cells. The synthesized analogue of nicotinamide riboside (NR), ara-F nicotinamide riboside (F-NR), inhibits nicotinamide ribose kinase (NRK) activity in vitro, reduces cellular NAD levels, and enhances FK866’s cytotoxicity in U251 glioblastoma cells, indicating a collaborative impact on cell death. Metabolic analyses reveal that F-NR undergoes conversion to fluorinated nicotinamide mononucleotide (F-NMN) and other metabolites, highlighting the intact NAD metabolic pathway in glioma cells. The activation of SARM1 by F-NMN, a potent NAD-consuming enzyme, is supported by the synergistic effect of CZ-48, a cell-permeable SARM1 activator. Temporal analysis underscores the sequential nature of events, establishing NAD depletion as a precursor to ATP depletion and eventual massive cell death. This study not only elucidates the molecular intricacies of glioblastoma cell death but also proposes a promising strategy to enhance FK866 efficacy through fluorinated NAD precursors, offering potential avenues for innovative therapeutic interventions in the challenging landscape of glioblastoma treatment.

Abstract Objectives Parents play a pivotal role in child development and several parental factors have been identified as risk or protective factors for childhood anxiety and depression. To assess and target these parental factors in interventions, there is a need for a comprehensive, easy‐to‐use instrument. Method This study aimed to investigate the psychometric properties of an adapted version of the Parenting to Reduce Child Anxiety and Depression Scale, PaRCADS(N) in a Norwegian community sample (N = 163) of parents of children aged 8–12 years. Results Our findings indicate that PaRCADS(N) has acceptable psychometric properties. These results are comparable to those of the original study of the PaRCADS in Australia. Conclusion Based on these results, we recommend that PaRCADS(N) can be utilized by health care workers as a tool for assessment and identification of parental practices related to child anxiety and/or depression to target relevant risk and protective factors in treatment and prevention.

SARM1 is a key player in axon degeneration. Here, the authors generate a nanobody, which specifically recognizes the NMN-bound state of SARM1 and helps resolve the SARM1 structure in an intermediate state of activation.

Abstract Voxel-based morphometry (VBM) is a popular non-invasive magnetic resonance imaging technique to investigate brain gray matter (GM) differences between groups. Recently, two VBM studies in migraine have been published in The Journal of Headache and Pain. Reviewing the two and those previous published VBM studies, we found considerable variations of the results. Spatially diverse brain regions with decreased and increased GM alterations and null findings have been reported. It is interesting to know whether there is a reliable brain morphological signature for migraine. Coordinate-based meta-analysis (CBMA) is increasingly used to quantitatively pool individual neuroimaging studies to identify consistent and reliable findings. Several CBMA have been conducted, however, their results were inconsistent. The algorithms for CBMA have evolved and more eligible VBM studies in migraine have been published. We therefore conducted an updated CBMA using the latest algorithms for CBMA, seed-based d mapping with permutation of subject images (SDM-PSI). The present CBMA of 32 VBM studies (41 datasets comprising 1252 patients and 1025 healthy controls) found no evidence of consistent GM alterations in migraine. Sensitivity analysis, subgroup meta-analyses, and meta-regression analyses revealed that the result was robust. This negative result indicates that there is no reliable brain morphological signature for migraine. VBM investigations in migraine remain a heterogeneous field. Many potential confounding factors, such as underpowered sample sizes, variations in demographic and clinical characteristics, and differences in MRI scanners, head coils, scanning parameters, preprocessing procedures, and statistical strategies may cause the inconsistences of the results. Future VBM studies are warranted to enroll well-characterized and homogeneous subtype samples with appropriate sample sizes, comprehensively assess comorbidities and medication status, and use well-validated and standardized imaging protocols and processing and analysis pipelines to produce robust and replicable results in migraine.

Summary: SARM1, an NAD-utilizing enzyme, regulates axonal degeneration. We show that CZ-48, a cell-permeant mimetic of NMN, activated SARM1 in vitro and in cellulo to cyclize NAD and produce a Ca2+ messenger, cADPR, with similar efficiency as NMN. Knockout of NMN-adenylyltransferase elevated cellular NMN and activated SARM1 to produce cADPR, confirming NMN was its endogenous activator. Determinants for the activating effects and cell permeability of CZ-48 were identified. CZ-48 activated SARM1 via a conformational change of the auto-inhibitory domain and dimerization of its catalytic domain. SARM1 catalysis was similar to CD38, despite having no sequence similarity. Both catalyzed similar set of reactions, but SARM1 had much higher NAD-cyclizing activity, making it more efficient in elevating cADPR. CZ-48 acted selectively, activating SARM1 but inhibiting CD38. In SARM1-overexpressing cells, CZ-48 elevated cADPR, depleted NAD and ATP, and induced non-apoptotic death. CZ-48 is a specific modulator of SARM1 functions in cells. : Biochemistry; Enzymology; Biochemical Mechanism Subject Areas: Biochemistry, Enzymology, Biochemical Mechanism

SARM1 regulates axonal degeneration through its NAD-metabolizing activity and is a drug target for neurodegenerative disorders. We designed and synthesized fluorescent conjugates of styryl derivative with pyridine to serve as substrates of SARM1, which exhibited large red shifts after conversion. With the conjugates, SARM1 activation was visualized in live cells following elevation of endogenous NMN or treatment with a cell-permeant NMN-analog. In neurons, imaging documented mouse SARM1 activation preceded vincristine-induced axonal degeneration by hours. Library screening identified a derivative of nisoldipine (NSDP) as a covalent inhibitor of SARM1 that reacted with the cysteines, especially Cys311 in its ARM domain and blocked its NMN-activation, protecting axons from degeneration. The Cryo-EM structure showed that SARM1 was locked into an inactive conformation by the inhibitor, uncovering a potential neuroprotective mechanism of dihydropyridines.

Abstract Background Preventive efforts targeting childhood anxiety and depression symptoms have the potential to alter the developmental trajectory of depression and anxiety disorders across the lifespan. Substantial previous research suggests that modifiable parenting factors such as parental aversiveness and over-involvement are associated with childhood anxiety, depressive and internalising symptoms, indicating that parents can play a critical role in prevention. The Parenting Resilient Kids study is a new evidence-based online parenting program designed to prevent anxiety and depression problems in primary school-aged children by reducing family-based risk factors and enhancing protective factors through increased positive interactions between parent and child. Methods/design The current study is a parallel group superiority randomised controlled trial with parent-child dyads randomised to the intervention or active-control group in a 1:1 ratio. The intervention group will receive the Parenting Resilient Kids program consisting of a feedback report on parenting behaviours and up to 12 interactive online modules personalised based on responses to the parent survey. The active-control group will receive a standardised package of online educational materials about child development and wellbeing. The trial website is programmed to run a stratified random allocation sequence (based on parent gender) to determine group membership. We aim to recruit 340 parent-child dyads (170 dyads per group). We hypothesise that the intervention group will show greater improvement in parenting risk and protective factors from baseline to 3-month follow-up (primary outcome), which will in turn mediate changes in child depressive and anxiety symptoms from baseline to 12 and 24 months (co-primary outcomes). We also hypothesise that the intervention group will show greater benefits from baseline to 3-, 12- and 24-month follow-up, with regard to: child depressive and anxiety symptoms (co-primary outcomes); and child and parent health-related quality of life, and overall family functioning (secondary outcomes). Discussion This randomised controlled trial will examine the efficacy of the Parenting Resilient Kids program as a preventive intervention for anxiety and depression symptoms in primary school-aged children, as well as changes in child and parent health-related quality of life. Findings from this study will examine design features that render web-based prevention programs effective and the extent to which parents can be engaged and motivated to change through a minimally guided parenting program. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR): Trial ID ACTRN12616000621415 Registered on 13 May 2016. Updated on 3 March 2017.

The cytokine transforming growth factor-β (TGF-β) can induce normal breast epithelial cells to take on a mesenchymal phenotype, termed epithelial-to-mesenchymal transition (EMT). While the transcriptional and proteomic changes during TGF-β-induced EMT have been described, the metabolic rewiring that occurs in epithelial cells undergoing EMT is not well understood. Here, we quantitively analyzed the TGF-β-induced metabolic reprogramming during EMT of non-transformed NMuMG mouse mammary gland epithelial cells using nuclear magnetic resonance (NMR) spectroscopy. We found that TGF-β elevates glycolytic and tricarboxylic acid (TCA)-cycle activity and increases glutaminolysis. Additionally, TGF-β affects the hexosamine pathway, arginine-proline metabolism, the cellular redox state, and strongly affects choline metabolism during EMT. TGF-β was found to induce phosphocholine production. A kinase inhibitor RSM-93A that inhibits choline kinase α (CHKα) mitigated TGF-β-induced changes associated with EMT, i.e., increased filamentous (F)-actin stress fiber formation and N-Cadherin mesenchymal marker expression.

Background Involving parents in the prevention of mental health problems in children is prudent given their fundamental role in supporting their child’s development. However, few measures encapsulate the range of risk and protective factors for child anxiety and depression that parents can potentially modify. The Parenting to Reduce Child Anxiety and Depression Scale (PaRCADS) was developed as a criterion-referenced measure to assess parenting against a set of evidence-based parenting guidelines for the prevention of child anxiety and depressive disorders. Methods In Study 1, 355 parents of children 8–11 years old across Australia completed the PaRCADS and measures of parenting, general family functioning, child anxiety and depressive symptoms, and parent and child health-related quality of life. Their children completed measures of parenting, anxiety and depressive symptoms, and health-related quality of life. In Study 2, six subject-experts independently evaluated the PaRCADS items for item-objective congruence and item-relevance. Item analysis was conducted by examining item-total point-biserial correlation, difficulty index, B-index, and expert-rated content validity indices. Reliability (or dependability) was assessed by agreement coefficients for single administration. Construct validity was examined by correlational analyses with other measures. Results Four items were removed to yield a 79-item, 10-subscale PaRCADS. Reliability estimates for the subscale and total score range from .74 to .94. Convergent validity was indicated by moderate to strong correlations with other parenting and family functioning measures, and discriminant validity was supported by small to moderate correlations with a measure of parents’ health-related quality of life. Higher scores on the PaRCADS were associated with fewer anxiety and depressive symptoms and better health-related quality of life in the child. PaRCADS total score was associated with parental age, parent reported child’s history of mental health diagnosis and child’s current mental health problem. Discussion Results showed that the PaRCADS demonstrates adequate psychometric properties that provide initial support for its use as a measure of parenting risk and protective factors for child anxiety and depression. The scale may be used for intervention and evaluative purposes in preventive programs and research.

Vascular endothelial growth factor (VEGF) signal transduction is central to angiogenesis in development and in pathological conditions such as cancer, retinopathy and ischemic diseases. However, no detailed mass-action models of VEGF receptor signaling have been developed. We constructed and validated the first computational model of VEGFR2 trafficking and signaling, to study the opposing roles of Gab1 and Gab2 in regulation of Akt phosphorylation in VEGF-stimulated endothelial cells. Trafficking parameters were optimized against 5 previously published in vitro experiments, and the model was validated against six independent published datasets. The model showed agreement at several key nodes, involving scaffolding proteins Gab1, Gab2 and their complexes with Shp2. VEGFR2 recruitment of Gab1 is greater in magnitude, slower, and more sustained than that of Gab2. As Gab2 binds VEGFR2 complexes more transiently than Gab1, VEGFR2 complexes can recycle and continue to participate in other signaling pathways. Correspondingly, the simulation results show a log-linear relationship between a decrease in Akt phosphorylation and Gab1 knockdown while a linear relationship was observed between an increase in Akt phosphorylation and Gab2 knockdown. Global sensitivity analysis demonstrated the importance of initial-concentration ratios of antagonistic molecular species (Gab1/Gab2 and PI3K/Shp2) in determining Akt phosphorylation profiles. It also showed that kinetic parameters responsible for transient Gab2 binding affect the system at specific nodes. This model can be expanded to study multiple signaling contexts and receptor crosstalk and can form a basis for investigation of therapeutic approaches, such as tyrosine kinase inhibitors (TKIs), overexpression of key signaling proteins or knockdown experiments.