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Expression of SMARCD1 interacts with age in association with asthma control on inhaled corticosteroid therapy.
BackgroundGlobal gene expression levels are known to be highly dependent upon gross demographic features including age, yet identification of age-related genomic indicators has yet to be comprehensively undertaken in a disease and treatment-specific context.MethodsWe used gene expression data from CD4+ lymphocytes in the Asthma BioRepository for Integrative Genomic Exploration (Asthma BRIDGE), an open-access collection of subjects participating in genetic studies of asthma with available gene expression data. Replication population participants were Puerto Rico islanders recruited as part of the ongoing Genes environments & Admixture in Latino Americans (GALA II), who provided nasal brushings for transcript sequencing. The main outcome measure was chronic asthma control as derived by questionnaires. Genomic associations were performed using regression of chronic asthma control score on gene expression with age in years as a covariate, including a multiplicative interaction term for gene expression times age.ResultsThe SMARCD1 gene (SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily D member 1) interacted with age to influence chronic asthma control on inhaled corticosteroids, with a doubling of expression leading to an increase of 1.3āunits of chronic asthma control per year (95% CI [0.86, 1.74], pā=ā6āĆā10-ā9), suggesting worsening asthma control with increasing age. This result replicated in GALA II (pā=ā3.8āĆā10-ā8). Cellular assays confirmed the role of SMARCD1 in glucocorticoid response in airway epithelial cells.ConclusionFocusing on age-dependent factors may help identify novel indicators of asthma medication response. Age appears to modulate the effect of SMARCD1 on asthma control with inhaled corticosteroids
Miscarriage and stillbirth following maternal Zika virus infection in nonhuman primates.
Zika virus (ZIKV) infection is associated with congenital defects and pregnancy loss. Here, we found that 26% of nonhuman primates infected with Asian/American ZIKV in early gestation experienced fetal demise later in pregnancy despite showing few clinical signs of infection. Pregnancy loss due to asymptomatic ZIKV infection may therefore be a common but under-recognized adverse outcome related to maternal ZIKV infection
Fetal Demise and Failed Antibody Therapy During Zika Virus Infection of Pregnant Macaques
Zika virus (ZIKV) infection of pregnant women is associated with pathologic complications of fetal development. Here, we infect pregnant rhesus macaques (Macaca mulatta) with a minimally passaged ZIKV isolate from Rio de Janeiro, where a high rate of fetal development complications was observed. The infection of pregnant macaques with this virus results in maternal viremia, virus crossing into the amniotic fluid (AF), and in utero fetal deaths. We also treated three additional ZIKV-infected pregnant macaques with a cocktail of ZIKV-neutralizing human monoclonal antibodies (nmAbs) at peak viremia. While the nmAbs can be effective in clearing the virus from the maternal sera of treated monkeys, it is not sufficient to clear ZIKV from AF. Our report suggests that ZIKV from Brazil causes fetal demise in non-human primates (NHPs) without additional mutations or confounding co-factors. Treatment with a neutralizing anti-ZIKV nmAb cocktail is insufficient to fully stop vertical transmission
AI is a viable alternative to high throughput screening: a 318-target study
: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNetĀ® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNetĀ® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery
Inhibition of IGF-1R Prevents Ionizing Radiation-Induced Primary Endothelial Cell Senescence
<div><p>Accelerated senescence is a primary response to cellular stresses including DNA damaging agents (e.g., ionizing radiation) and is widely believed to be caused by continuous proliferative signaling in the presence of cell cycle arrest. Studies of signal transduction pathways leading to accelerated senescence have revealed that inhibition of mammalian target of rapamycin (mTOR) by rapamycin rescues cells from senescence. However, the molecular mechanisms upstream of mTOR following ionizing radiation (IR) are not well defined. We investigated signal transduction leading to IR-induced accelerated senescence in human pulmonary artery endothelial cells (HPAEC). Exposure of HPAEC to X-rays (10 Gy, 2.4 Gy/min) upregulated senescence markers including p53, p21/waf1, and senescence-associated beta galactosidase (SA-Ī²-gal). Ly294002 (a phosphatidylinositol-3-kinase [PI3K] inhibitor) or rapamycin (an mTOR inhibitor) blocked the induction of cellular senescence markers suggesting roles for PI3K and mTOR. Pathway-directed microarrays revealed increased transcription of insulin-like growth factor I (IGF-1), a modulator of cell growth and proliferation upstream of mTOR. qRT-PCR confirmed that both IGF-1 and IGF-2 mRNA were increased in response to X-rays, and ELISA showed increased secretion of IGF-1 protein into the medium of irradiated HPAEC. Consistent with upregulation of these ligands, we found that X-ray exposure led to hyperphosphorylation of IGF-1R, the receptor for IGF-1 and -2. Treatment with AG1024, an IGF-1R inhibitor, suppressed IR-induced upregulation of p53, p21/waf1, and SA-Ī²-gal. Together these findings suggest that IGF-1R is a key regulator of IR-induced accelerated senescence in a pathway that requires intact mTOR activity upstream of both p53 and p21/waf1. </p> </div
IR-induced IGF-1R-mediated accelerated senescence requires intact mTOR.
<p>Subconfluent HPAEC were treated with 5 Ī¼M AG1024 or DMSO for 30 minutes and subjected to 10 Gy X-rays. At 3 and 72 hours post-irradiation, whole cell lysates were prepared and western blotting for phospho-S6 (Ser 235/236) was performed.</p