Biology subjects

Terrando, N.

Publications and source records attributed to Terrando, N..

7 recordsLinked to original sources

bioRxiv2025

Pericytes Repair Engineered Defects in the Basement Membrane to Restore Barrier Integrity in an in vitro Model of the Blood-Brain Barrier.

Pericytes play a key role in the brain where they support the blood-brain barrier (BBB). Their loss has been reported in response to systemic inflammation and neurodegenerative disease. We recently demonstrated that iPSC-derived brain pericyte-like cells (BPLCs) and brain microvascular endothelial cell (BMEC)-like cells collaboratively form a nascent, 3D basement membrane when cultured across a nanoporous membrane1. Building on this, we aimed to engineer defects in the basement membrane to investigate whether pericytes could facilitate its repair. In BMEC monocultures, we observed that micropore patterns in nanomembranes created discontinuities in laminin, which destabilized barrier function. Remarkably, the addition of pericytes to the basal side of the membrane restored both laminin integrity and barrier function. Our results align with the role of pericytes as support cells for microvasculature and encourage the use of our tissue barrier platform (the {micro}SiM) to model neurological disorders involving pericyte dysfunction and/or disruption of basement membrane.

bioengineering↗

bioRxiv2023

Neutrophilia with damage to the blood-brain barrier and neurovascular unit following acute lung injury

BackgroundThe role of neutrophils in mediating neurovascular vulnerability has been increasingly implicated in various acute inflammatory models of neuroimmune crosstalk between the periphery and the brain. Whether neurovascular vulnerability is similarly modulated in the context of frequent, but not acute, inflammatory activation in the periphery is the aim of our study. Such a model of frequent inflammatory irritation is pertinent to understanding the neurologic risk of constant exposure to aerosolized environmental hazards leading to progressive pulmonary disease. MethodsTo model repeated pulmonary inflammation, we applied a three-dose regimen of intranasal (i.n.) lipopolysaccharide (LPS) in C57BL/6J mice and studied the impact on the inflammatory environment of the brain, with a specific focus on neutrophil dynamics at the neurovascular unit (NVU). Tissue and circulatory inflammatory profiles were screened via bronchoalveolar lavage (BAL) protein content and cellularity, transcript analysis of brain tissue, and flow cytometry of peripheral blood. Intravital two-photon microscopy (2PM) of the brain vasculature identified neutrophil dynamics at the NVU. Immunofluorescence validated neutrophil dynamics and identified neuroinflammatory hallmarks and peripheral immune factor interactions at the NVU. In vivo findings were corroborated and replicated in murine and human microphysiological systems (MPS) modeling the blood-brain barrier as a proxy demonstration of the translational relevance of our findings. Results2PM of tdTomato-Ly6G+ neutrophils demonstrated increased levels of circulating neutrophils and corresponding engagement with the brain vasculature after the three-dose repeated i.n. exposure regimen. Neutrophilia at the NVU was corroborated with increased transcript levels of Ly6G and other pro-inflammatory markers. This coordination between endothelial physiology and neutrophil phenotypes was recapitulated in murine and human MPS models. System-wide neutrophilia in the lung and circulation was found to be cotemporaneous to neutrophilia at the NVU based on the cellularity of BAL and peripheral blood samples collected at the same endpoints. Immunohistochemical analysis of brain tissue implicates temporal coordination between vascular surface adhesion molecules with changes in neutrophil dynamics from adhesion, crawling, stalling, and transmigration. Extravasation of neutrophils was complemented by sustained paravascular deposition of fibrinogen and microgliosis up to 72 hours after the final i.n. dosing. Microglia-associated effector functions for synaptic pruning and regulation of neutrophil activity demonstrated distinct temporal profiles. ConclusionsOur results identify systemic levels of neutrophilia accompanied by ingress and extravascular accumulation in brain parenchyma that correlated with sustained microglial activation. This neutrophil-centric lung-brain interaction is complemented by the observation of paravascular fibrinogen deposition that alters synaptic metabolism. Thus, we propose a mechanistic role for neutrophilia and associated inflammatory dysregulation as essential mediators along the lung-brain neuroimmune axis in a generalizable model of repeated respiratory exposure to inflammatory agents. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=119 SRC="FIGDIR/small/562508v2_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@113d747org.highwire.dtl.DTLVardef@19a8a5corg.highwire.dtl.DTLVardef@f1a1eaorg.highwire.dtl.DTLVardef@1bd23c7_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

bioRxiv2023

Vagus nerve stimulation rescues persistent pain following orthopedic surgery in adult mice.

Postoperative pain is a major clinical problem imposing a significant burden on our patients and society. Up to 57% of patients experience persistent postoperative pain 2 years after orthopedic surgery [49]. Although many studies have contributed to the neurobiological foundation of surgery-induced pain sensitization, we still lack safe and effective therapies to prevent the onset of persistent postoperative pain. We have established a clinically relevant orthopedic trauma model in mice that recapitulates common insults associated with surgery and ensuing complications. Using this model, we have started to characterize how induction of pain signaling contributes to neuropeptides changes in dorsal root ganglia (DRG) and sustained neuroinflammation in the spinal cord [62]. Here we have extended the characterization of pain behaviors for >3 months after surgery, describing a persistent deficit in mechanical allodynia in both male and female C57BL/6J mice after surgery. Notably, we have applied a novel minimally invasive bioelectronic approach to percutaneously stimulate the vagus nerve (termed pVNS) [24] and tested its anti-nociceptive effects in this model. Our results show that surgery induced a strong bilateral hind-paw allodynia with a slight decrease in motor coordination. However, treatment with pVNS for 30-minutes at10 Hz weekly for 3 weeks prevented pain behavior compared to naive controls. pVNS also improved locomotor coordination and bone healing compared to surgery without treatment. In the DRGs, we observed that vagal stimulation fully rescued activation of GFAP positive satellite cells but did not affect microglial activation. Overall, these data provide novel evidence for the use of pVNS to prevent postoperative pain and may inform translational studies to test anti-nociceptive effects in the clinic.

neuroscience↗

bioRxiv2022

Conserved YKL-40 changes in mice and humans after postoperative delirium.

Delirium is a common postoperative neurologic complication among older adults. Despite its prevalence of 14-50% and likely association with inflammation, the exact mechanisms underlying postoperative delirium are unclear. This project aimed at characterizing systemic and central nervous system (CNS) inflammatory changes following surgery in both mice and humans. Matched plasma and cerebrospinal fluid (CSF) samples from the "Investigating Neuroinflammation Underlying Postoperative Brain Connectivity Changes, Postoperative Cognitive Dysfunction, Delirium in Older Adults" (INTUIT; NCT03273335) were used to parallel murine endpoints. Delirium-like behavior was evaluated in aged mice using the 5-Choice Serial Reaction Time Test (5-CSRTT). Using a well-established orthopedic surgical model in the FosTRAP reporter mouse, we detected neuronal changes in the prefrontal cortex, an area implicated in attention, but notably not in the hippocampus. In aged mice, plasma interleukin-6 (IL-6), chitinase-3-like protein 1 (YKL-40), and neurofilament light chain (NfL) levels increased after orthopedic surgery, but hippocampal YKL-40 expression was decreased. Given the growing role of YKL-40 in delirium and other neurodegenerative conditions, we assayed human plasma and CSF samples. Plasma YKL-40 levels were also similarly increased after surgery, with a trend toward greater post-operative plasma YKL-40 increase in patients with delirium. In contrast to plasma, YKL-40 levels in CSF decreased following surgery, which paralleled the findings in the mouse brain. Finally, we confirmed changes in blood-brain barrier (BBB) after surgery as early as 9 hours in mice, which warrants for more detailed and acute evaluations of BBB integrity following surgery in humans. All together, these results provide a nuanced understanding of the neuroimmune interactions underlying post-operative delirium in mice and humans, and highlight translational biomarkers to test potential cellular targets and mechanisms.

neuroscience↗

bioRxiv2021

URMC-099 Prophylaxis Repairs Hippocampal Vascular Damage in an Orthopedic Model of Delirium Superimposed on Dementia

Systemic perturbations can drive a neuroimmune cascade after surgical trauma, including affecting the blood-brain barrier (BBB), activating microglia, and contributing to cognitive deficits such as delirium. Delirium superimposed on dementia (DSD) is a particularly debilitating complication that renders the brain further vulnerable to neuroinflammation and neurodegeneration, albeit these molecular mechanisms remain poorly understood. Here we have used an orthopedic model of tibial fracture/fixation in APPSwDI/mNos2-/- AD (CVN-AD) mice to investigate relevant pathogenetic mechanisms underlying DSD. We conducted the present study in 6 months-old CVN-AD mice, an age at which we speculated amyloid-{beta} pathology had not saturated BBB and neuroimmune functioning. We found that URMC-099, our brain-penetrant anti-inflammatory neuroprotective drug, prevented inflammatory endothelial activation, breakdown of the BBB, synapse loss, and microglial activation in our DSD model. Taken together, our data link post-surgical endothelial activation, microglial MafB immunoreactivity, and synapse loss as key substrates for DSD, all of which can be prevented by URMC-099.

neuroscience↗

bioRxiv2020

Annexin-A1 tripeptide attenuates surgery-induced neuroinflammation and memory deficits through regulation of the NLRP3 inflammasome

Neuroinflammation is a growing hallmark of perioperative neurocognitive disorders (PNDs), including delirium and longer-lasting cognitive deficits. We have developed a clinically-relevant orthopedic mouse model to study the impact of a common surgical procedure on the vulnerable brain. The mechanism underlying PNDs remain unknown. Here we evaluated the impact of surgical trauma on the NLRP3 inflammasome signaling, including the expression of apoptosis-associated speck-like protein containing a CARD (ASC), caspase-1, and IL-1{beta} in the hippocampus of C57BL6/J male mice, adult (3-months) and aged (>18-months). Surgery triggered ASC specks formation in CA1 hippocampal microglia, but without inducing significant morphological changes in NLRP3 and ASC knockout mice. Since no therapies are currently available to treat PNDs, we assessed the neuroprotective effects of a biomimetic peptide derived from the endogenous inflammation-ending molecule, Annexin-A1 (ANXA1). We tested the hypothesis that this peptide (ANXA1sp) inhibits NLRP3 inflammasome activation, thus preventing microglial activation and hippocampal-dependent memory deficits. Together these results uncover a previously underrecognized role of the NLRP3 inflammasome in triggering postoperative neuroinflammation and offer a new target for advancing treatment of PNDs through resolution of inflammation.

neuroscience↗

bioRxiv2019

The broad spectrum mixed-lineage kinase 3 inhibitor URMC-099 prevents acute microgliosis and cognitive decline in a mouse model of perioperative neurocognitive disorders

Perioperative neurocognitive disorders (PND), including delirium and postoperative cognitive dysfunction, are serious complications that afflict up to 50% of surgical patients and for which there are no disease-modifying therapeutic options. Here, we test whether prophylactic treatment with the broad spectrum mixed-lineage kinase 3 inhibitor URMC-099 prevents surgery-induced neuroinflammation and cognitive impairment in a translational model of orthopedic surgery-induced PND. We used a combination of two-photon scanning laser microscopy and CLARITY with light-sheet microscopy to define surgery-induced changes in microglial dynamics and morphology. Orthopedic surgery induced widespread microglial activation in the hippocampus and cortex that accompanied impairments in episodic memory. URMC-099 prophylaxis prevented these neuropathological sequelae without impacting bone fracture healing. Together, these findings provide compelling evidence for the advancement of URMC-099 as a therapeutic option for PND.

neuroscience↗