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The dynamic interplay between mental health difficulties and the family environment in early adolescence
Background: Adolescents experiencing mental health problems have an elevated risk of persisting difficulties as they transition into adulthood, stressing the importance of identifying modifiable factors impacting mental health during adolescence. The family environment is recognised as a key influence on adolescent mental health in theory and interventions. Notably, few studies have disentangled within-person and between-person effects in relating adolescent mental health and the family environment. Methods: We analysed data from 1067 adolescents across three waves using panel graphical vector autoregressive modelling, separating contemporaneous and temporal within-person and between-person associations in relationships between mental health difficulties (i.e., emotional, hyperactivity/inattention, conduct problems) and family-related factors (i.e., aspects of the general family environment, parent-child relationships, and sibling dynamics). We also assessed how the different mental health difficulties and family environment factors were themselves interrelated over time. The mean age (in years) was 10.51 at Wave 1, 12.49 at Wave 2, and 14.49 at Wave 3. Results: Emotional symptoms predicted increases in hyperactivity/inattention and more sibling problems over time. Lack of family support and negative feelings towards family were reciprocally related, indicative of a reinforcing loop. Both mental health difficulties and family environment factors exhibited considerable stability. In contemporaneous within-person associations, mental health difficulties were strongly interrelated, as were aspects of the family environment. Furthermore, conduct problems were linked to externalising behaviours (e.g., fighting with parents, bothering siblings) and emotional symptoms to internalising experiences of family dynamics (e.g., feeling negative towards family, being bothered by siblings). Negative feelings towards family and hyperactivity/inattention were strongly predicted by included variables, while emotional symptoms, fighting with parents, and lacking family support were predictive of other variables. Conclusions: Our findings point to the importance of emotional problems in adolescence, which may contribute to worsened hyperactivity/inattention and more problems with siblings over time, and the interrelatedness of mental health and the family environment. Alleviating internalising problems in affected adolescents may help mitigate development of other mental health difficulties and negative sibling dynamics.
Brain signatures of nociplastic pain: Fibromyalgia Index and descending modulation at population level.
Nociplastic pain is defined by altered nociceptive processing in the absence of clear peripheral damage or somatosensory lesions. The Fibromyalgia Index (FMI), derived from the 2016 diagnostic criteria, is increasingly used as a marker of nociplastic pain severity in clinical studies, yet its neurobiological validity remains untested at scale. Using multimodal neuroimaging data from over 40,000 participants in UK Biobank, we examined whether FMI scores were associated with altered functional and structural connectivity within the descending pain modulatory system (DPMS), a brain network involved in endogenous pain control and implicated in nociplastic pain conditions. Functional connectivity was assessed using resting-state functional MRI (rfMRI), and structural connectivity using diffusion-weighted MRI (dMRI) tractography. Connectivity was quantified between seven DPMS regions: periaqueductal grey (PAG), rostral ventromedial medulla (RVM), hypothalamus, amygdala, rostral and subgenual anterior cingulate cortex (rACC, sgACC), and dorsolateral prefrontal cortex (dlPFC). Multi-group structural equation models (SEMs) tested associations between FMI scores and connectivity, stratified by chronic pain status. Mediation models evaluated which aspects of nociplastic pain accounted for the observed associations: widespread pain and SPACE symptoms (Sleep disturbance, Pain, Affect, Cognitive problems, and low Energy). To assess specificity, we repeated analyses using the Douleur Neuropathique 4 (DN4), a measure of neuropathic pain, and average pain intensity as comparison outcomes. In 22,139 individuals with chronic pain (58% female; mean age 64.8, SD 7.59) FMI scores were associated with altered structural connectivity between the PAG and amygdala (β=0.023, 95%CI: 0.0087 to 0.039; Pcorr=0.0125) and between the PAG and hypothalamus (β= -0.029, 95%CI: -0.043 to -0.015; Pcorr =0.0013). Functional connectivity in the same circuits showed smaller effects. These associations were not observed in individuals without chronic pain. Mediation analyses revealed that PAG-amygdala and PAG-hypothalamus connectivity were partially explained by fatigue, sleep duration, and widespread pain. DPMS connectivity was not significantly associated with neuropathic pain or average pain intensity. These findings suggest that FMI scores reflect biologically meaningful changes in brain connectivity, particularly in subcortical DPMS circuits implicated in affective and homeostatic dimensions of pain. Structural connectivity was more strongly associated with FMI than functional measures, possibly reflecting cumulative effects of chronic pain on white matter architecture. The absence of similar associations for other pain outcomes supports the specificity of FMI as a marker of nociplastic pain severity. These results provide a neurobiological basis for the FMI and support its use in population research and biomarker development for nociplastic pain.
TDP-43 pathology is associated with divergent protein profiles in ALS brain and spinal cord.
Neuronal and glial cytoplasmic inclusions positive for TAR DNA-binding protein 43 (TDP-43) are the defining pathological hallmark of 97% of amyotrophic lateral sclerosis (ALS) and 50% of frontotemporal dementia (FTD). The ALS-FTD clinicopathological spectrum variably involves cortical and spinal anterior horn cell pathology. The broader protein composition of these inclusions is of major importance to understanding pathogenesis, clinical heterogeneity and biomarker development. This study examined the proteome associated with TDP-43 inclusions in ALS, using mass spectrometry-based proteomic analysis of spinal cord and cerebral cortex from donors with phosphoTDP-43 positive ALS (n = 16), alpha-synuclein positive Parkinson's disease (PD, n = 8), phosphotau and beta-amyloid positive Alzheimer's disease (AD, n = 8) and age matched non-neurological controls (n = 8), comparing ALS with non-ALS conditions, spinal cord with cerebral cortex samples, and detergent-soluble with -insoluble fractions. Increased abundance of TDP-43 in the detergent-insoluble fraction of ALS cortex and spinal cord tissue confirmed disease-specific protein enrichment by serial fractionation. The most striking alterations between ALS and other conditions were found in the detergent-insoluble fraction of spinal cord, with predominant enrichment of endosomal and extracellular vesicle pathways. In the cortex mitochondrial membrane/envelope and ion transmembrane transport pathways were enriched in the detergent-insoluble fraction. RNA/DNA metabolic processes (in spinal cord) versus mitochondrial and synaptic protein pathways (in cortex) were upregulated in the detergent-soluble fraction of ALS cases and downregulated in the insoluble protein fraction. Whilst motor cortex and spinal cord may not optimally reflect disease-specific pathways in AD, in PD a significant enrichment of alpha-synuclein in the detergent-insoluble fraction of spinal cord was found. Among proteins concordantly elevated in the detergent-insoluble fractions of spinal cord and cortex, there was greater representation of proteins encoded by ALS-associated genes, specifically Cu/Zn superoxide dismutase 1, valosin containing protein and TDP-43 (odds ratio 16.34, p = 0.002). No significant increase in TDP-43 interacting proteins was observed in either detergent-soluble or -insoluble fractions. Together, this study shows a divergence in the composition of proteins associated with TDP-43 positive detergent-insoluble inclusions between spinal cord and cerebral cortex. A common upregulation of proteins encoded by ALS-causing genes implicates their role in the pathogenesis of the ALS-FTD spectrum of diseases beyond TDP-43. Data are available via ProteomeXchange with identifier PXD067060.
Risk and protective factors of healthy cognitive ageing across diverse global cohorts and causal effect of education
The global rise in cognitive impairment calls for preventive strategies through early identification of risk and protective factors in the community, healthy elderly, that take into account cultural and geographic diversity. This study investigates how risk and protective factors influence cognitive functioning and depressive symptoms of older adults across six diverse cohorts (n=1,636) from Europe, Asia, and Australia. We found that younger age at baseline and longer education covary with better baseline cognitive function, with a marginal average effect of education beyond individual, geographical, and birth cohort differences. Harnessing multimodal brain MRI, we nd that this relationship is mediated by normalised grey matter, with a statistically significant pooled effect across cohorts. Using a natural experiment, we then establish the causal effect of education on cognition six decades later. By including underrepresented populations and by generalising findings, this research extends the evidence base beyond dominant Western-focused research norms, underscoring a call for inclusive and equitable access to education to enhance lifelong cognitive trajectories
SLC45A4 is a pain gene encoding a neuronal polyamine transporter.
Polyamines are regulatory metabolites with key roles in transcription, translation, cell signalling and autophagy1. They are implicated in multiple neurological disorders, including stroke, epilepsy and neurodegeneration, and can regulate neuronal excitability through interactions with ion channels2. Polyamines have been linked to pain, showing altered levels in human persistent pain states and modulation of pain behaviour in animal models3. However, the systems governing polyamine transport within the nervous system remain unclear. Here, undertaking a genome-wide association study (GWAS) of chronic pain intensity in the UK Biobank (UKB), we found a significant association between pain intensity and variants mapping to the SLC45A4 gene locus. In the mouse nervous system, Slc45a4 expression is enriched in all sensory neuron subtypes within the dorsal root ganglion, including nociceptors. Cell-based assays show that SLC45A4 is a selective plasma membrane polyamine transporter, and the cryo-electron microscopy (cryo-EM) structure reveals a regulatory domain and basis for polyamine recognition. Mice lacking SLC45A4 show normal mechanosensitivity but reduced sensitivity to noxious heat- and algogen-induced tonic pain that is associated with reduced excitability of C-polymodal nociceptors. Our findings therefore establish a role for neuronal polyamine transport in pain perception and identify a target for therapeutic intervention in pain treatment.
Cardiac intermediary metabolism in heart failure: substrate use, signalling roles and therapeutic targets.
The number of patients with heart failure is expected to rise sharply owing to ageing populations, poor dietary habits, unhealthy lifestyles and improved survival rates from conditions such as hypertension and myocardial infarction. Heart failure is classified into two main types: heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). These forms fundamentally differ, especially in how metabolism is regulated, but they also have shared features such as mitochondrial dysfunction. HFrEF is typically driven by neuroendocrine activation and mechanical strain, which demands a higher ATP production to sustain cardiac contraction. However, the primary energy source in a healthy heart (fatty acid β-oxidation) is often suppressed in HFrEF. Although glucose uptake increases in HFrEF, mitochondrial dysfunction disrupts glucose oxidation, and glycolysis and ketone oxidation only partially compensate for this imbalance. Conversely, HFpEF, particularly in individuals with metabolic diseases, such as obesity or type 2 diabetes mellitus, results from both mechanical and metabolic overload. Elevated glucose and lipid levels overwhelm normal metabolic pathways, leading to an accumulation of harmful metabolic byproducts that impair mitochondrial and cellular function. In this Review, we explore how disruptions in cardiac metabolism are not only markers of heart failure but also key drivers of disease progression. We also examine how metabolic intermediates influence signalling pathways that modify proteins and regulate gene expression in the heart. The growing recognition of the role of metabolic alterations in heart failure has led to groundbreaking treatments that target these metabolic disruptions, offering new hope for these patients.
AAV microdystrophin gene replacement therapy for Duchenne muscular dystrophy: progress and prospects.
Duchenne muscular dystrophy (DMD) is caused by pathogenic sequence variants occurring in the DMD gene which lead to the loss of the dystrophin protein, a molecular 'shock absorber' that protects muscle from contraction-induced injury. The large size of the dystrophin open reading frame precludes delivery of the full-length protein using a single adeno-associated virus (AAV) vector, which led to the development of internally-deleted dystrophin minigenes encoding partially-functional dystrophin. Indeed, five such microdystrophin therapies have been assessed in various clinical programmes. In 2023, Elevidys (Sarepta Therapeutics) received accelerated approval based on levels of dystrophin as a surrogate biomarker. In 2024, it received full approval despite unclear efficacy (i.e. not meeting primary or secondary outcomes in a phase 3 trial). Additionally, in 2025, two DMD individuals treated with Elevidys died after acute liver failure. A separate microdystrophin therapy, PF-06939926 (Pfizer) was discontinued for both efficacy and safety reasons (including the deaths of two clinical trial participants). Solid Biosciences, Genethon, REGENXBIO, and Insmed continue to develop microdystrophin therapies differing in transgene structure, promoter sequences, and AAV serotype. Here we describe recent progress in AAV-microdystrophin therapeutics development, and discuss the challenges facing such approaches, including pre-existing anti-capsid immunity, anti-transgene immunity, the unknown functionality of microdystrophin transgenes, transduction of muscle stem cells, and long-term transgene persistence.
Changes in sensorimotor network dynamics in resting-state recordings in Parkinson's disease.
Non-invasive recordings of magnetoencephalography have been used for developing biomarkers for neural changes associated with Parkinson's disease that can be measured across the entire course of the disease. These studies, however, have yielded inconsistent findings. Here, we investigated whether analysing motor cortical activity within the context of large-scale brain network activity provides a more sensitive marker of changes in Parkinson's disease using magnetoencephalography. We extracted motor cortical beta power and beta bursts from resting-state magnetoencephalography scans of patients with Parkinson's disease (N = 28) and well-matched healthy controls (N = 36). To situate beta bursts in their brain network contexts, we used a time-delay-embedded hidden Markov model to extract brain network activity and investigated co-occurrence patterns between brain networks and beta bursts. Parkinson's disease was associated with decreased beta power in motor cortical power spectra, but no significant differences in motor cortical beta-burst dynamics occurred when using a conventional beta-burst analysis. Dynamics of a large-scale sensorimotor network extracted with the time-delay-embedded hidden Markov model approach revealed significant decreases in the occurrence of this network with Parkinson's disease. By comparing conventional burst and time-delay-embedded hidden Markov model state occurrences, we observed that motor beta bursts occurred during both sensorimotor and non-sensorimotor network activations. When using the large-scale network information provided by the time-delay-embedded hidden Markov model to focus on bursts that were active during sensorimotor network activations, significant decreases in burst dynamics could be observed in patients with Parkinson's disease. In conclusion, our findings suggest that decreased motor cortical beta power in Parkinson's disease is prominently associated with changes in sensorimotor network dynamics using magnetoencephalography. Thus, investigating large-scale networks or considering the large-scale network context of motor cortical activations may be crucial for identifying alterations in the sensorimotor network that are prevalent in Parkinson's disease and might help resolve contradicting findings in the literature.
Alcohol Use and Risk of Dementia in Diverse Populations: Evidence from Cohort, Case-control and Mendelian randomization Approaches
Objectives To investigate the relationship between alcohol consumption and dementia. Design Prospective cohort and case-control analyses combined with linear and nonlinear Mendelian randomization. Setting Two large-scale population-based cohorts: the US Million Veteran Program and UK Biobank. Genetic analyses used summary statistics from genome-wide association studies (GWAS). Participants 559,559 adults aged 56–72 years at baseline were included in observational analyses (mean follow-up: 4 years in the US cohort; 12 years in the UK cohort). Genetic analyses used summary data from multiple large GWAS consortia (2.4 million participants). Main outcome measures Incident all-cause dementia, determined through health record linkage, and genetic proxies. Results During follow-up, 14,540 participants developed dementia and 48,034 died. Observational phenotype-only analyses revealed U-shaped associations between alcohol and dementia risk: higher risk was observed among non-drinkers, heavy drinkers (>40 drinks per week; hazard ratio [HR]=1.41, 95% confidence interval[CI] 1.15-1.74), and those with alcohol use disorder (AUD) (HR=1.51[CI 1.42-1.60]) compared with light drinkers. In contrast, Mendelian randomization genetic analysis identified a monotonic increase in dementia risk with greater alcohol consumption. A one standard deviation increase in log-transformed drinks per week was associated with a 15% dementia increase (IVW OR=1.15[1.03-1.27]). A two-fold increase in AUD prevalence was associated with a 16% increase in dementia risk (inverse-variance weighted [IVW] OR=1.16[1.03-1.30]). Alcohol intake increased dementia, but individuals who developed dementia also experienced a decline in alcohol intake over time, suggesting reverse causation—where early cognitive decline leads to reduced alcohol consumption— underlies the supposed protective alcohol effects in observational studies. Conclusions These findings provide evidence for a relationship between all types of alcohol use and increased dementia risk. While correlational observational data suggested a protective effect of light drinking, this could be in part attributable to reduced drinking seen in early dementia; genetic analyses did not support this, suggesting that any level of alcohol consumption may contribute to dementia risk. Public health strategies that reduce the prevalence of alcohol use disorder could potentially lower the incidence of dementia by up to 16%.
Will Human-Animal Chimeras Cause Moral Confusion? Exploring Public Attitudes.
Recent medical research involving human-monkey chimeras, human brain organoids in rats, and the transplantation of a gene-edited pig heart and gene-edited pig kidneys in living human beings have intensified the debate about whether we should create human-animal chimeras for biomedical purposes and, if so, how we should treat them. Influential views in the debate frequently appeal to assumptions regarding how people will react to such chimeras. It has, for example, been argued that the most important objection against creating such chimeras is that this will result in inexorable moral confusion about species boundaries and will, as a result, threaten the social order. But is this indeed the case? We conducted three empirical studies to examine laypeople's views on the creation and treatment of various types of human-animal chimeras. Our studies indicate that laypeople find typical cases of xenotransplantation (i.e., the transplantation of an animal organ into a human patient) morally unproblematic. They assign the same moral status to humans with animal organs as to non-chimeric humans. By contrast, they sometimes (but not always) assign slightly higher moral status to animals with human organs than to non-chimeric animals. Overall, however, there is little indication of chimera technology blurring the line between humans and animals, and thus of the technology causing moral confusion.
A cross-species analysis of neuroanatomical covariance sex differences in humans and mice.
BACKGROUND: Structural covariance within the brain is thought to reflect inter-regional sharing of developmental influences. This hypothesis has proved difficult to test but can be informatively probed by the study of sex differences. Here, we use neuroimaging in humans and mice to study sex-differences in anatomical covariance- asking (1) are there sex differences in structural covariance and (2) do regions that share the same developmental influences, as exhibited by shared sex differences in volume, also show shared sex differences in volume covariance. This study design illuminates both the biology of sex-differences and theoretical models for anatomical covariance- benefitting from tests of inter-species convergence. METHODS: Brain volume correlations for males and females across 255 regions in mice (n = 423) and 378 regions in humans (n = 436) were calculated using volumetric measures obtained from structural MRI. Mean correlations for each sex were compared within species to determine whether covariance sex differences exist. Specific covariances with strong sex differences in each species were identified via permutation tests for statistical significance. Brain maps of regional average structural covariance sex-bias were generated for mice and humans. Regional average structural covariance sex-bias and volumetric sex-bias were correlated to identify whether these features align in their direction of sex-bias. RESULTS: We find that volumetric structural covariance is stronger in adult females than males for both wild-type mice and healthy human subjects: 98% of comparisons with statistically significant covariance sex differences in mice are female-biased, while 76% of such comparisons are female-biased in humans (q