Citations

With rapid industrial expansion, air pollution’s adverse neurological effects have gained increasing attention. Children face a greater risk of neurological damage because of their higher breathing rates, developing brains, and limited ability to detoxify harmful substances. Fine particulate matter has been identified as a primary neurotoxic contributor affecting developing brains. Strong evidence connects environmental pollutant exposure to the prevalence of Autism Spectrum Disorder (ASD), a neurodevelopmental condition marked by lasting difficulties with social communication and interaction. This study explores the association between long-term PM2.5 exposure and ASD symptom exacerbation, investigating underlying mechanisms. We hypothesize that long-term PM2.5 exposure exacerbates ASD symptoms through neuroinflammatory activation, leading to neuronal damage and impaired synaptic plasticity. Our investigation employs three complementary approaches: First, integrated analysis combining Global Burden of Disease data with Mendelian randomization demonstrates a significant association between PM2.5 exposure and increased ASD severity risk. Second, utilizing the China High-Resolution Air Pollution Database in conjunction with cohort studies, we provide evidence that ambient air pollution substantially influences autism severity, with PM2.5 identified as the predominant environmental determinant. Third, through network toxicology, single-cell transcriptomics, and animal experimentation, we demonstrate that chronic PM2.5 exposure exacerbates valproic acid-induced autism-like behaviors in murine models, identifying CTNNB1, PTEN, CCR2, AKT1, and mTOR as potential core mediating genes. Importantly, these findings represent preliminary results. Several potential confounding factors such as co-exposure to other pollutants and socioeconomic variables have not been fully addressed. While our multi-modal approach provides converging lines of evidence, further validation in larger, more diverse populations with refined control of confounders will be essential to establish causality and elucidate mechanisms. Nonetheless, these early insights advance our understanding of PM2.5-induced neurotoxicity in the context of ASD and offer timely, albeit preliminary, evidence to inform public health policy.

Introduction : The incidence of spontaneous clinical improvement in acute cardiomyopathy (ACM) patients treated with evidence based medical therapy is unknown. We hypothesized that pts without LV dilatation at presentation would have the greatest potential for recovery of ejection fraction (EF). Methods: A multi-center NHLBI sponsored trial, Intervention in Myocarditis and Acute Cardiomyopathy II (IMAC 2) was designed to study the clinical course of ACM and the mechanisms associated with outcomes. A clinical, echocardiography, and genetics core lab are established. Results: 15 centers have enrolled 215 pts, mean age 45 ± 14 yrs, 34% female, NYHA class I–IV% 18/54/21/7, baseline EF 0.25 ± 0.09. Therapy included 80% beta blockers and 92% ACE or ARB treated. All patients enrolled had symptoms for ≤ 6 mos and were diagnosed with acute, idiopathic cardiomyopathy or myocarditis. Baseline and 6 mo echoes in 140 pts reviewed by the core lab demonstrated increased ejection fraction (EF): 0.25 ± 0.09 to 0.40 ± 0.11 p<0.001; mean increase 0.15 ± 0.10. Recovery in EF from baseline to 6 mos was related to LVEDD at baseline as shown in the Figure . Kaplan Meier survival n=207 at 1 and 2 years 96% and 94% and transplant free survival at 1 and 2 yrs 92% and 91%. Conclusions: Results of IMAC 2 reveal a marked spontaneous improvement in EF over 6 months, greatest in those with non-dilated LVEDD at baseline, and excellent overall survival in ACM pts treated with evidence based therapies.

Excess fat within bone marrow is associated with lower bone density. Metabolic stressors such as chronic caloric restriction (CR) can exacerbate marrow adiposity, and increased glucocorticoid signaling and adrenergic signaling are implicated in this phenotype. The current study tested the role of glucocorticoid signaling in CR-induced stress by conditionally deleting the glucocorticoid receptor ( Nr3c1 ; hereafter abbreviated as GR) in bone marrow osteoprogenitors (Osx1-Cre) of mice subjected to CR and ad libitum diets. Conditional knockout of the GR (GR-CKO) reduced cortical and trabecular bone mass as compared to WT mice under both ad libitum feeding and CR conditions. No interaction was detected between genotype and diet, suggesting that the GR is not required for CR-induced skeletal changes. The lower bone mass in GR-CKO mice, and the further decrease in bone by CR, resulted from suppressed bone formation. Interestingly, treatment with the β-adrenergic receptor antagonist propranolol mildly but selectively improved metrics of cortical bone mass in GR-CKO mice during CR, suggesting interaction between adrenergic and glucocorticoid signaling pathways that affects cortical bone. GR-CKO mice dramatically increased marrow fat under both ad libitum and CR-fed conditions, and surprisingly propranolol treatment was unable to rescue CR-induced marrow fat in either WT or GR-CKO mice. Additionally, serum corticosterone levels were selectively elevated in GR-CKO mice with CR, suggesting the possibility of bone–hypothalamus–pituitary–adrenal crosstalk during metabolic stress. This work highlights the complexities of glucocorticoid and β-adrenergic signaling in stress-induced changes in bone mass, and the importance of GR function in suppressing marrow adipogenesis while maintaining healthy bone mass.