270. Independent mechanisms of inflammation and myeloid bias in VEXAS syndrome.
作者: Varun K Narendra.;Tandrila Das.;Linsey J Wierciszewski.;Rebecca J Londoner.;Joshua K Morrison.;Pia Martindale.;Tessa Devine.;Kevin Chen.;Michael Trombetta.;Yuzuka Kanno.;Alejandro E Casiano.;Elisa de Stanchina.;Caleb A Lareau.;Scott W Lowe.;Alexander D Gitlin.
来源: Nature. 2025年
Somatically acquired mutations in the E1 ubiquitin-activating enzyme UBA1 within hematopoietic stem and progenitor cells (HSPCs) were recently identified as the cause of the adult-onset autoinflammatory syndrome VEXAS (vacuoles, E1 enzyme, X linked, autoinflammatory, somatic)1. UBA1 mutations in VEXAS lead to clonal expansion within the HSPC and myeloid, but not lymphoid, compartments. Despite its severity and prevalence, the mechanisms whereby UBA1 mutations cause multiorgan autoinflammation and hematologic disease are unknown. Here, we employ somatic gene editing approaches to model VEXAS-associated UBA1 mutations in primary macrophages and HSPCs. Uba1-mutant macrophages exposed to inflammatory stimuli underwent aberrant apoptotic and necroptotic cell death mediated by Caspase-8 and RIPK3-MLKL, respectively. Accordingly, in mice challenged with TNF or LPS, the UBA1 inhibitor TAK-243 exacerbated inflammation in a RIPK3-Caspase-8-dependent manner. In contrast, Uba1 mutation in HSPCs induced an unfolded protein response and myeloid bias independently of RIPK3-Caspase-8. Mechanistically, aberrant cell death of Uba1-mutant macrophages coincided with a kinetic defect in Lys63/Met1 (i.e., linear) polyubiquitylation of inflammatory signaling complexes. Collectively, our results link VEXAS pathogenesis with that of rarer monogenic autoinflammatory syndromes; highlight specific ubiquitin-associated defects stemming from an apical mutation in the ubiquitylation cascade; and support therapeutic targeting of the inflammatory cell death axis in VEXAS.
271. Accelerating the discovery of multicatalytic cooperativity.
Cooperative catalysis, in which multiple catalytic units operate synergistically, underpins a variety of synthetically and mechanistically important organic reactions1-4. Despite its potential utility in new reactivity contexts, approaches to the discovery of cooperative catalysts have been limited, typically relying on serendipity or on prior knowledge of single-catalyst reactivity1,5. Systematic searches for unanticipated types of catalyst cooperativity must contend with vast combinatorial complexity and are therefore not undertaken6-10. Here, we describe a pooling-deconvolution algorithm, inspired by group testing11, that identifies cooperative catalyst behaviors with low experimental cost while accommodating potential inhibitory effects between catalyst candidates. The workflow was validated first on simulated cooperativity data, and then by experimentally identifying previously documented cooperativity between organocatalysts in an enantioselective oxetane-opening reaction. The workflow was then applied in a discovery context to a Pd-catalyzed decarbonylative cross-coupling reaction, enabling the identification of several ligand pairs that promote the target transformation at substantially lower catalyst loading and temperature than previously reported with single ligand systems.
272. Brain dynamics reflecting an intra-network brain state is associated with increased posttraumatic stress symptoms in the early aftermath of trauma.
作者: Mohammad Se Sendi.;Zening Fu.;Nathaniel G Harnett.;Sanne J H van Rooij.;Victor Vergara.;Diego A Pizzagalli.;Nikolaos P Daskalakis.;Stacey L House.;Francesca L Beaudoin.;Xinming An.;Thomas C Neylan.;Gari D Clifford.;Tanja Jovanovic.;Sarah D Linnstaedt.;Laura T Germine.;Kenneth A Bollen.;Scott L Rauch.;John P Haran.;Alan B Storrow.;Christopher Lewandowski.;Paul I Musey.;Phyllis L Hendry.;Sophia Sheikh.;Christopher W Jones.;Brittany E Punches.;Robert A Swor.;Nina T Gentile.;Vishnu P Murty.;Lauren A Hudak.;Jose L Pascual.;Mark J Seamon.;Erica Harris.;Anna M Chang.;Claire Pearson.;David A Peak.;Roland C Merchant.;Robert M Domeier.;Niels K Rathlev.;Brian J O'Neil.;Paulina Sergot.;Leon D Sanchez.;Steven E Bruce.;John F Sheridan.;Steven E Harte.;Ronald C Kessler.;Karestan C Koenen.;Samuel A McLean.;Jennifer S Stevens.;Vince D Calhoun.;Kerry J Ressler.
来源: Nat Ment Health. 2025年3卷2期185-198页
Post-traumatic stress (PTS) encompasses a range of psychological responses following trauma, which may lead to more severe outcomes such as post-traumatic stress disorder (PTSD). Identifying early neuroimaging biomarkers that link brain function to PTS outcomes is critical for understanding PTSD risk. This longitudinal study examines the association between brain dynamic functional network connectivity (dFNC) and current/future PTS symptom severity, and the impact of sex on this relationship. By analyzing 275 participants' dFNC data obtained ~2 weeks after trauma exposure, we noted that brain dynamics of an inter-network brain state link negatively with current (r=-0.197, pcorrected = 0.0079) and future (r=-0.176, pcorrected = 0.0176) PTS symptom severity. Also, dynamics of an intra-network brain state correlated with future symptom intensity (r = 0.205, pcorrected = 0.0079). We additionally observed that the association between the network dynamics of the inter-network and intra-network brain state with symptom severity is more pronounced in female group. Our findings highlight a potential link between brain network dynamics in the aftermath of trauma with current and future PTSD outcomes, with a stronger effect in female group, underscoring the importance of sex differences.
|