Costantino Iadecola

Background: Non-traumatic intracerebral hemorrhage (ICH) is independently associated with long-term increased risk of major arterial ischemic events. Whether hematoma volume influences this risk is poorly understood. Methods: We pooled individual patient data from the MISTIE III (Minimally Invasive Surgery Plus Alteplase for Intracerebral Hemorrhage Evacuation phase 3) and the ATACH-2 (Antihypertensive Treatment of Acute Cerebral Hemorrhage) trials. The exposure was hematoma volume. In the primary analysis, hematoma volume was treated as a continuous measure after natural logarithmic transformation to approximate linearity, and in the secondary analysis, it was dichotomized by the median. The outcome was an ischemic stroke, adjudicated centrally within each trial. We evaluated the association between hematoma volume and the risk of an ischemic stroke using Cox regression analyses after …

Hypertension (HTN), a disease afflicting over one billion individuals worldwide, is a leading cause of cognitive impairment, the mechanisms of which remain poorly understood. In the present study, in a mouse model of HTN, we find that the neurovascular and cognitive dysfunction depends on interleukin (IL)-17, a cytokine elevated in individuals with HTN. However, neither circulating IL-17 nor brain angiotensin signaling can account for the dysfunction. Rather, IL-17 produced by T cells in the dura mater is the mediator released in the cerebrospinal fluid and activating IL-17 receptors on border-associated macrophages (BAMs). Accordingly, depleting BAMs, deleting IL-17 receptor A in brain macrophages or suppressing meningeal T cells rescues cognitive function without attenuating blood pressure elevation, circulating IL-17 or brain angiotensin signaling. Our data unveil a critical role of meningeal T cells and …

Objective Although acute brain infarcts are common after surgical aortic valve replacement (SAVR), they are often unassociated with clinical stroke symptoms. The relationship between clinically “silent” infarcts and in‐hospital delirium remains uncertain; obscured, in part, by how infarcts have been traditionally summarized as global metrics, independent of location or structural consequence. We sought to determine if infarct location and related structural connectivity changes were associated with postoperative delirium after SAVR. Methods A secondary analysis of a randomized multicenter SAVR trial of embolic protection devices (NCT02389894) was conducted, excluding participants with clinical stroke or incomplete neuroimaging (N = 298; 39% female, 7% non‐White, 74 ± 7 years). Delirium during in‐hospital recovery was serially screened using the Confusion Assessment Method. Parcellation and …

Acute depletion of meningeal lymphatic vessels impairs the clearance of cerebrospinal fluid and brain macromolecules. A new study by Antila et al. shows that amyloid pathology in Alzheimer’s disease is neither improved nor aggravated by genetic expansion or depletion of meningeal lymphatic vessels.

ImportanceCerebral amyloid angiopathy (CAA) is a common cause of spontaneous intracerebral hemorrhage in older patients. Although other types of intracranial hemorrhage can occur in conjunction with CAA-related intracerebral hemorrhage, the association between CAA and other subtypes of intracranial hemorrhage, particularly in the absence of intracerebral hemorrhage, remains poorly understood.ObjectiveTo determine whether CAA is an independent risk factor for isolated nontraumatic subdural hemorrhage (SDH).Design, Setting, and ParticipantsA population-based cohort study was performed using a 2-stage analysis of prospectively collected data in the UK Biobank cohort (discovery phase, 2006-2022) and the All of Us Research Program cohort (replication phase, 2018-2022). Participants included those who contributed at least 1 year of data while they were older than 50 years, in accordance with the …

Ubiquitin modifications alter protein function and stability, thereby regulating cell homeostasis and viability, particularly under stress. Ischemic stroke induces protein ubiquitination at the ischemic periphery, wherein cells remain viable, however the identity of ubiquitinated proteins is unknown. Here, we employed a proteomics approach to identify these proteins in mice undergoing ischemic stroke. The data are available in a searchable web interface (https://hochrainerlab.shinyapps.io/StrokeUbiOmics/). We detected increased ubiquitination of 198 proteins, many of which localize to the postsynaptic density (PSD) of glutamatergic neurons. Among these were proteins essential for maintaining PSD architecture, such as PSD95, as well as NMDA and AMPA receptor subunits. The largest enzymatic group at the PSD with elevated post-ischemic ubiquitination were kinases, such as CaMKII, PKC, Cdk5, and Pyk2, whose …

Neurofluids is a term introduced to define all fluids in the brain and spine such as blood, cerebrospinal fluid, and interstitial fluid. Neuroscientists in the past millennium have steadily identified the several different fluid environments in the brain and spine that interact in a synchronized harmonious manner to assure a healthy microenvironment required for optimal neuroglial function. Neuroanatomists and biochemists have provided an incredible wealth of evidence revealing the anatomy of perivascular spaces, meninges and glia and their role in drainage of neuronal waste products. Human studies have been limited due to the restricted availability of noninvasive imaging modalities that can provide a high spatiotemporal depiction of the brain neurofluids. Therefore, animal studies have been key in advancing our knowledge of the temporal and spatial dynamics of fluids, for example, by injecting tracers with different …

Elevated blood pressure is a well-established risk factor for age-related cognitive decline. Long linked to cognitive impairment on vascular bases, increasing evidence suggests a potential association of hypertension with the neurodegenerative pathology underlying Alzheimer disease. Hypertension is well known to disrupt the structural and functional integrity of the cerebral vasculature. However, the mechanisms by which these alterations lead to brain damage, enhance Alzheimer pathology, and promote cognitive impairment remain to be established. Furthermore, critical questions concerning whether lowering blood pressure by antihypertensive medications prevents cognitive impairment have not been answered. Recent developments in neurovascular biology, brain imaging, and epidemiology, as well as new clinical trials, have provided insights into these critical issues. In particular, clinical and basic findings …