Human primary (hpBMEC) and induced pluripotent stem cell (iPSC)-derived brain microvascular endothelial-like cells (hiBMEC) are interchangeably used in blood-brain barrier models to study neurological diseases and drug delivery. Both hpBMEC and hiBMEC use glutamine as a source of carbon and nitrogen to produce metabolites and build proteins essential to cell function and communication. We used metabolomic, transcriptomic, and computational methods to examine how hpBMEC and hiBMEC metabolize glutamine, which may impact their utility in modeling the blood-brain barrier. We found that glutamine metabolism was systemically different between the two cell types. hpBMEC had a higher metabolic rate and produced more glutamate and GABA, while hiBMEC rerouted glutamine to produce more glutathione, fatty acids, and asparagine. Higher glutathione production in hiBMEC correlated with higher oxidative stress compared to hpBMEC. α-ketoglutarate (α-KG) supplementation increased glutamate secretion from hiBMEC to match that of hpBMEC; however, α-KG also decreased hiBMEC glycolytic rate. These fundamental metabolic differences between BMEC types may impactin vitroblood-brain barrier model function, particularly communication between BMEC and surrounding cells, and emphasize the importance of evaluating the metabolic impacts of iPSC-derived cells in disease models.
more »
« less
Early and enduring: Targeting the endothelium for blood-brain barrier protection
The disruption of the blood-brain barrier marks a pivotal early pathological event in ischemic stroke that significantly contributes to subsequent permanent damage. Here we delve into the ramifications of a study conducted by Xu and colleagues, which underscores the essential role of the protein peroxiredoxin-4 in cerebrovascular endothelial cells. Peroxiredoxin-4 was shown to preserve blood-brain barrier integrity during the early stages after cerebral ischemia and reperfusion, ultimately leading to improved long-term outcomes.
more »
« less
- Award ID(s):
- 1916894
- PAR ID:
- 10523787
- Publisher / Repository:
- Sage Journals
- Date Published:
- Journal Name:
- Journal of Cerebral Blood Flow & Metabolism
- ISSN:
- 0271-678X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Following traumatic brain injury (TBI), secondary brain damage due to chronic inflammation is the most predominant cause of the delayed onset of mood and memory disorders. Currently no therapeutic approach is available to effectively mitigate secondary brain injury after TBI. One reason is the blood–brain barrier (BBB), which prevents the passage of most therapeutic agents into the brain. Peptides have been among the leading candidates for CNS therapy due to their low immunogenicity and toxicity, bioavailability, and ease of modification. In this study, we demonstrated that non-invasive intranasal (IN) administration of KAFAK, a cell penetrating anti-inflammatory peptide, traversed the BBB in a murine model of diffuse, moderate TBI. Notably, KAFAK treatment reduced the production of proinflammatory cytokines that contribute to secondary injury. Furthermore, behavioral tests showed improved or restored neurological, memory, and locomotor performance after TBI in KAFAK-treated mice. This study demonstrates KAFAK’s ability to cross the blood–brain barrier, to lower proinflammatory cytokines in vivo, and to restore function after a moderate TBI.more » « less
-
Treating the brain is challenging due to the restrictive blood–brain barrier, and modulus-mismatched implants often cause problems. Herein, we have fabricated copolymer hydrogels from thermoresponsive polymer, poly(N-isopropylacrylamide) (PNIPAAm), -r-hydrophilic polymer, poly(acrylic acid) (PAA), which are injectable and transform into soft implants above their lower critical solution temperature (LCST). PAA concentration can be leveraged to tune the LCST and viscosity of the PNIPAAm–r–PAA hydrogel in solution. Furthermore, the Young’s moduli of these materials, ranging from 1-4 kPa, are close to rat and human brain tissue, potentially leading to less inflammation and rejection due to significant modulus mismatch.more » « less
-
Regoes, Roland R. (Ed.)While highly active antiretroviral therapy (HAART) is successful in controlling the replication of Human Immunodeficiency Virus (HIV-1) in many patients, currently there is no cure for HIV-1, presumably due to the presence of reservoirs of the virus. One of the least studied viral reservoirs is the brain, which the virus enters by crossing the blood-brain barrier (BBB) via macrophages, which are considered as conduits between the blood and the brain. The presence of HIV-1 in the brain often leads to HIV associated neurocognitive disorders (HAND), such as encephalitis and early-onset dementia. In this study we develop a novel mathematical model that describes HIV-1 infection in the brain and in the plasma coupled via the BBB. The model predictions are consistent with data from macaques infected with a mixture of simian immunodeficiency virus (SIV) and simian-human immunodeficiency virus (SHIV). Using our model, we estimate the rate of virus transport across the BBB as well as viral replication inside the brain, and we compute the basic reproduction number. We also carry out thorough sensitivity analysis to define the robustness of the model predictions on virus dynamics inside the brain. Our model provides useful insight into virus replication within the brain and suggests that the brain can be an important reservoir causing long-term viral persistence.more » « less
-
Abstract Recent developments in digital light processing (DLP) can advance the structural and biochemical complexity of perfusablein vitromodels of the blood–brain barrier. Here, we describe a strategy to functionalize complex, DLP-printed vascular models with multiple peptide motifs in a single hydrogel. Different peptides can be clicked into the walls of distinct topologies, or the peptide motifs lining channel walls can differ from those in the bulk of the hydrogel. The flexibility of this approach is used to both characterize the effects of various bioactive domains on endothelial coverage and tight junction formation, in addition to facilitating astrocyte attachment in the hydrogel surrounding the endothelialized vessel to mimic endothelial–astrocyte interaction. Peptides derived from proteins mediating cell-extracellular matrix (e.g. RGD and IKVAV) and cell–cell (e.g. HAVDI) adhesions are used to mediate endothelial cell attachment and coverage. HAVDI and IKVAV-lined channels exhibit significantly greater endothelialization and increased zonula-occluden-1 (ZO-1) localization to cell–cell junctions of endothelial cells, indicative of tight junction formation. RGD is then used in the bulk hydrogel to create an endothelial–astrocyte co-culture model of the blood–brain barrier that overcomes the limitations of previous platforms incapable of complex topology or tunable bioactive domains. This approach yields an adjustable, biofabricated platform to interrogate the effects of cell-matrix interaction on blood–brain barrier mechanobiology.more » « less
An official website of the United States government

