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Ushio-Fukai, M.

Publications and source records attributed to Ushio-Fukai, M..

4 recordsLinked to original sources

Endothelial Cu Uptake Transporter CTR1 Senses Disturbed Flow to Promote Atherosclerosis through Cuproptosis

Endothelial cells (ECs) lining blood vessels sense disturbed blood flow (D-flow), which drives mitochondrial dysfunction and atherosclerosis. Copper (Cu) is an essential micronutrient, and its disruption of homeostasis has been implicated in atherosclerosis. Cellular Cu levels are tightly controlled by Cu transport proteins including the Cu importer CTR1. Cuproptosis is a recently discovered form of regulated cell death triggered by mitochondrial Cu accumulation, but its endogenous stimulants and role in atherosclerosis remain unknown. Using EC-specific CTR1-deficient mice and cultured ECs, we show that endothelial CTR1 responds to D-flow by increasing mitochondrial Cu levels through its interaction with the mitochondrial Cu transporter SLC25A3 at caveolae/lipid rafts. This leads to the aggregation of lipoylated mitochondrial proteins, mitochondrial dysfunction, and cuproptosis, thereby exacerbating atherosclerosis. Importantly, mitochondria-targeted Cu-chelating nanoparticles effectively mitigate D-flow-induced cuproptosis and atherosclerosis, highlighting the endothelial CTR1-SLC25A3-mitochondrial Cu axis as a potential therapeutic target.

cell biology↗

Altered Copper Transport in Oxidative Stress-Dependent Brain Endothelial Barrier Dysfunction Associated with Alzheimer's Disease

Oxidative stress and blood-brain barrier (BBB) disruption due to brain endothelial barrier dysfunction contribute to Alzheimers Disease (AD), which is characterized by beta-amyloid (A{beta}) accumulation in senile plaques. Copper (Cu) is implicated in AD pathology and its levels are tightly controlled by several Cu transport proteins. However, their expression and role in AD, particularly in relation to brain endothelial barrier function remains unclear. In this study, we examined the expression of Cu transport proteins in the brains of AD mouse models as well as their involvement in A{beta}42-induced brain endothelial barrier dysfunction. We found that the Cu uptake transporter CTR1 was upregulated, while the Cu exporter ATP7A and/or ATP7B were downregulated in the hippocampus of AD mouse models, and in A{beta}42-treated human brain microvascular endothelial cells (hBMECs). In the 5xFAD AD mouse model, Cu levels (assessed by ICP-MS) were elevated in the hippocampus. Moreover, A{beta}42-induced reactive oxygen species (ROS) production, ROS-dependent loss in barrier function in hBMEC (measured by transendothelial electrical resistance), and tyrosine phosphorylation of VE-cadherin were all inhibited by either a membrane permeable Cu chelator or by knocking down CTR1 expression. These findings suggest that dysregulated expression of Cu transport proteins may lead to intracellular Cu accumulation in the AD brain, and that A{beta}42 promotes ROS-dependent brain endothelial barrier dysfunction and VE-Cadherin phosphorylation in a CTR1-Cu-dependent manner. Our study uncovers the critical role of Cu transport proteins in oxidative stress-related loss of BBB integrity in AD. HighlightsO_LIUpregulation of the Cu importer CTR1 and downregulation of the Cu exporter ATP7A in the hippocampus of AD mouse models C_LIO_LIA{beta}42 increases CTR1 expression while reduces ATP7A and ATP7B levels in human brain microvascular ECs. C_LIO_LIA{beta}42 triggers increased reactive oxygen species (ROS) production in human brain microvascular ECs through a CTR1- and Cu-dependent manner. C_LIO_LIA{beta}42 induces endothelial barrier dysfunction in human brain microvascular ECs through a CTR1-Cu-ROS-pendent manner. C_LI

neuroscience↗

Endothelial Drp1 Couples VEGF-induced Redox Signaling with Glycolysis Through Cysteine Oxidation to Drive Angiogenesis

Angiogenesis plays a vital role for postnatal development and tissue repair following ischemia. Reactive oxygen species (ROS) generated by NADPH oxidases (NOXes) and mitochondria act as signaling molecules that promote angiogenesis in endothelial cells (ECs) which mainly relies on aerobic glycolysis for ATP production. However, the connections linking redox signaling with glycolysis are not well understood. The GTPase Drp1 is a member of the dynamin superfamily that moves from cytosol to mitochondria through posttranslational modifications to induce mitochondrial fission. The role of Drp1 in ROS-dependent VEGF signaling and angiogenesis in ECs has not been previously described. Here, we identify an unexpected function of endothelial Drp1 as a redox sensor, transmitting VEGF-induced H2O2 signals to enhance glycolysis and angiogenesis. Loss of Drp1 expression in ECs inhibited VEGF-induced angiogenic responses. Mechanistically, VEGF rapidly induced the NOX4-dependent sulfenylation (CysOH) of Drp1 on Cys644, promoting disulfide bond formation with the metabolic kinase AMPK and subsequent sulfenylation of AMPK at Cys299/304 via the mitochondrial fission-mitoROS axis. This cysteine oxidation of AMPK, in turn, enhanced glycolysis and angiogenesis. In vivo, mice with EC-specific Drp1 deficiency or CRISPR/Cas9-engineered "redox-dead" (Cys to Ala) Drp1 knock-in mutations exhibited impaired retinal angiogenesis and post-ischemic neovascularization. Our findings uncover a novel role for endothelial Drp1 in linking VEGF-induced mitochondrial redox signaling to glycolysis through a cysteine oxidation-mediated Drp1-AMPK redox relay, driving both developmental and reparative angiogenesis.

cell biology↗

Myeloid Drp1 Deficiency Limits Revascularization in Ischemic Muscles via Inflammatory Macrophage Polarization and Metabolic Reprograming

In the preclinical model of peripheral arterial disease (PAD), M2-like anti-inflammatory macrophage polarization and angiogenesis are required for revascularization. The regulation of cell metabolism and inflammation in macrophages is tightly linked to mitochondrial dynamics. Drp1, a mitochondrial fission protein, has shown context-dependent macrophage phenotypes with both pro- and anti-inflammatory characteristics. However, the role of macrophage Drp1 in reparative neovascularization remains unexplored. Here we show that Drp1 expression was significantly increased in F4/80+ macrophages within ischemic muscle at day 3 after hindlimb ischemia (HLI), an animal model of PAD. Myeloid-specific Drp1-/- mice exhibited reduced limb perfusion recovery, angiogenesis and muscle regeneration after HLI. These effects were associated with an increase in pro-inflammatory M1-like macrophages, p-NFkB and TNF, and reduced anti-inflammatory M2-like macrophages and p-AMPK in ischemic muscle of myeloid Drp1-/- mice. In vitro, Drp1-/- macrophages under hypoxia serum starvation (HSS), an in vitro PAD model, demonstrated enhanced glycolysis via reducing p-AMPK as well as mitochondrial dysfunction and excessive mitochondrial ROS, resulting in increased M1-gene and reduced M2-gene expression. Conditioned media from HSS-treated Drp1-/- macrophages exhibited increased secretion of pro-inflammatory cytokines and suppressed angiogenic responses in cultured endothelial cells. Thus, Drp1 deficiency in macrophages under ischemia drives inflammatory metabolic reprogramming and macrophage polarization, thereby limiting revascularization in experimental PAD.

cell biology↗