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1.
J Cereb Blood Flow Metab ; 44(3): 355-366, 2024 03.
Article En | MEDLINE | ID: mdl-37933727

Intracerebral hemorrhage (ICH) mobilizes circulating leukocytes that contribute to neuroinflammation and neural injury. However, little is known about the endogenous regulatory immune mechanisms to restrict neuroinflammation following ICH. We examined the role of group 2 innate lymphoid cells (ILC2) that are a specialized subset of innate immune modulators in a mouse model of ICH. We found accumulation of ILC2 in the brain following acute ICH and a concomitant increase of ILC2 within the peripheral lymph nodes. Depletion of ILC2 exacerbated neurodeficits and brain edema after ICH in male and female mice. This aggravated ICH injury was accompanied by augmented microglia activity and leukocyte infiltration. In contrast, expansion of ILC2 using IL-33 led to reduced ICH injury, microglia activity and leukocyte infiltration. Notably, elimination of microglia using a colony stimulating factor 1 receptor inhibitor diminished the exacerbation of ICH injury induced by depletion of ILC2. Brain-infiltrating ILC2 had upregulation of IL-13 after ICH. Results from in vitro assays revealed that ILC2 suppressed thrombin-induced inflammatory activity in microglia-like BV2 cells. Thus, our findings demonstrate that ILC2 suppress neuroinflammation and acute ICH injury.


Brain Injuries , Immunity, Innate , Male , Female , Mice , Animals , Neuroinflammatory Diseases , Lymphocytes/metabolism , Cerebral Hemorrhage/pathology , Brain Injuries/metabolism , Microglia/metabolism
2.
Stroke Vasc Neurol ; 8(5): 424-434, 2023 10.
Article En | MEDLINE | ID: mdl-37072337

BACKGROUND: Acute brain ischaemia elicits pronounced inflammation, which aggravates neural injury. However, the mechanisms governing the resolution of acute neuroinflammation remain poorly understood. In contrast to regulatory T and B cells, group 2 innate lymphoid cells (ILC2s) are immunoregulatory cells that can be swiftly mobilised without antigen presentation; whether and how these ILC2s participate in central nervous system inflammation following brain ischaemia is still unknown. METHODS: Leveraging brain tissues from patients who had an ischaemic stroke and a mouse model of focal ischaemia, we characterised the presence and cytokine release of brain-infiltrating ILC2s. The impact of ILC2s on neural injury was evaluated through antibody depletion and ILC2 adoptive transfer experiments. Using Rag2-/-γc-/- mice receiving passive transfer of IL-4-/- ILC2s, we further assessed the contribution of interleukin (IL)-4, produced by ILC2s, in ischaemic brain injury. RESULTS: We demonstrate that ILC2s accumulate in the areas surrounding the infarct in brain tissues of patients with cerebral ischaemia, as well as in mice subjected to focal cerebral ischaemia. Oligodendrocytes were a major source of IL-33, which contributed to ILC2s mobilisation. Adoptive transfer and expansion of ILC2s reduced brain infarction. Importantly, brain-infiltrating ILC2s reduced the magnitude of stroke injury severity through the production of IL-4. CONCLUSIONS: Our findings revealed that brain ischaemia mobilises ILC2s to curb neuroinflammation and brain injury, expanding the current understanding of inflammatory networks following stroke.


Brain Injuries , Brain Ischemia , Stroke , Humans , Mice , Animals , Immunity, Innate , Interleukin-4 , Lymphocytes , Neuroinflammatory Diseases , Inflammation
3.
Anal Methods ; 15(2): 171-178, 2023 Jan 06.
Article En | MEDLINE | ID: mdl-36504026

Surface chemistry of electrodes plays a critical role in the fields of electrochemistry and electric-field-assisted separation. In this study, making ingenious use of the ordered mesoporous structure of silica materials and the electrochemical stability of ionic liquids (ILs) when integrated with polyvinylpyrrolidone (PVP), the PVP-modified IL-mesoporous silica/platinum wire (Pt/PVP@meso-SiO2@IL) was fabricated to increase hydroelectric stability and avoid the problem of electrode polarization. The effect of different amounts of mesoporous silica material used to modify the surface of the Pt electrode was systematically investigated. As a result, we successfully obtained a highly ordered mesoporous Pt/PVP@meso-SiO2 material with smooth surface. Because pentyl triethylamine bis(trifluoromethylsulfonyl) imide exhibits a wide electrochemical window between -3 to 3 V, this IL was chosen to modify mesopores under vacuum. Even after repeatedly applying electric field on Pt/PVP@meso-SiO2@IL 100 times, this working electrode remained stable and showed high hydroelectric stability. After verifying the feasibility of this method, it was successfully applied in the electric-field-assisted separation of 2.0 and 3.0 µm polystyrene particles without any impediment from electrode polarization problems. This work provides a brand-new insight for resolving the problem of electrode polarization by developing a versatile tool for the electroseparation of micro-objects.

4.
FASEB J ; 36(12): e22616, 2022 12.
Article En | MEDLINE | ID: mdl-36394527

Cerebral ischemia activates neural progenitors that participate in brain remodeling following acute injury. Sphingosine-1-phosphate receptor (S1PR) signaling governs cell proliferation and mobilization, yet its potential impact on neural progenitors and stroke recovery remains poorly understood. The goal of this study was to investigate the impact of S1PR modulation on post-stroke neurogenesis and functional recovery, using a S1PR modulator BAF312. Mice were subjected to 60 min middle cerebral artery occlusion (MCAO) and received BAF312 starting from day 3 after MCAO until the end of experiment. BAF312 facilitated motor function recovery in MCAO mice until day 14 after surgery. Flow cytometry analysis revealed that BAF312 treatment led to an increase of type A cells in subventricular zone (SVZ), but not other progenitor cell subsets in MCAO mice. We found an increase of BrdU incorporation in SVZ DCX+ cells from MCAO mice receiving BAF312 and augmented proliferation of DCX+ cells in cultured neurospheres isolated from SVZ tissues. Notably, a S1PR1 antagonist W146 abolished BAF312-induced increase of SVZ type A cells from MCAO mice and proliferation of DCX+ cells in cultured neurospheres. Additionally, the benefit of BAF312 to improve neurogenesis and stroke recovery remains in Rag2-/- mice lacking of T and B cells. Our results demonstrate that S1PR modulation improves neurogenesis and functional recovery following brain ischemia.


Brain Ischemia , Stroke , Mice , Animals , Recovery of Function , Sphingosine-1-Phosphate Receptors , Neurogenesis/physiology , Stroke/drug therapy , Infarction, Middle Cerebral Artery
6.
Anal Chem ; 94(23): 8474-8482, 2022 06 14.
Article En | MEDLINE | ID: mdl-35652329

A circular nonuniform electric field strategy coupled with gel electrophoresis was proposed to control the precise separation and efficient concentration of nano- and microparticles. The circular nonuniform electric field has the feature of exponential increase in the electric field intensity along the radius, working with three functional zones of migration, acceleration, and concentration. The distribution form of electric field lines is regulated in functional zones to control the migration behaviors of particles for separation and concentration by altering the relative position of the ring electrode (outside) and rodlike electrode (inner). The circular nonuniform electric field promotes the target-type and high-precision separation of nanoparticles based on the difference in charge-to-size ratio. The concentration multiple of nanoparticles is also controlled randomly with the alternation of radius, taking advantage of vertical extrusion and concentric converging of the migration path. This work provides a brand new insight into the simultaneous separation and concentration of particles and is promising for developing a versatile tool for the separation and preparation of various samples instead of conventional methods.


Electricity , Nanoparticles , Electrodes , Electrophoresis/methods , Particle Size
7.
Acta Biomater ; 146: 197-210, 2022 07 01.
Article En | MEDLINE | ID: mdl-35487423

Exposure to a nuclear accident or a radiological attack may cause serious death events due to ionizing radiation-induced injury and acute radiation syndrome (ARS). Recombinant human granulocyte colony-stimulating factor (G-CSF) is now used for the treatment of ARS. However, the current injection formulation might not ensure treatment as early as possible after a nuclear accident, resulting in a decrease in therapeutic efficiency. In the present study, we have developed a G-CSF wearable system (GWS) consisting of a commercial microchip, a temperature sensor, a gamma-ray detection sensor, a flexible heater, and a G-CSF temperature-sensitive microneedle (GTSMN) patch. G-CSF-containing hyaluronic acid solutions were cast into the mold to obtain G-CSF microneedles (GMNs), which were coated with a temperature-sensitive layer of dodecanoic acid-cetylamine salt to obtain GTSMNs. The flexible heater was prepared by jet printing Ag nanoparticle inks. The GWS and its components are explored and optimized in the aspects of electronics, mechanics, heat transfer and drug diffusion. The γ radiation signal is sensitively monitored by the GWS. The wearable G-CSF system immediately releases G-CSF into the body in response to signal feedback and provides maximal protection against ionizing radiation-induced injury. Therefore, the GWS is a promising wearable system against emergent ionizing radiation injury. STATEMENT OF SIGNIFICANCE: Ionizing radiation-induced injury is always the very important public health problem all the global people care. Some medicines have been applied to protect the body from the injury. Unfortunately, sometimes the injuries accidently happen and the medicines cannot be administered in time, leading to serious acute radiation syndrome. Here, we design a wearable system loading G-CSF that has been approved by FDA to protect the body from ionizing radiation-induced injury. This system consists of a commercial microchip, a temperature sensor, a Gamma-ray detection sensor, a flexible heater, and a G-CSF temperature-sensitive microneedle patch. It can monitor γ radiation and immediately release G-CSF into the body to protect the body to the maximal extent. Therefore, the system is a promising wearable medical device against emergent ionizing radiation injury.


Acute Radiation Syndrome , Metal Nanoparticles , Wearable Electronic Devices , Acute Radiation Syndrome/drug therapy , Gamma Rays , Granulocyte Colony-Stimulating Factor/pharmacology , Granulocyte Colony-Stimulating Factor/therapeutic use , Humans , Radiation, Ionizing , Recombinant Proteins/therapeutic use , Silver
8.
Cell Death Dis ; 13(1): 33, 2022 01 10.
Article En | MEDLINE | ID: mdl-35013119

Aged microglia display augmented inflammatory activity after neural injury. Although aging is a risk factor for poor outcome after brain insults, the precise impact of aging-related alterations in microglia on neural injury remains poorly understood. Microglia can be eliminated via pharmacological inhibition of the colony-stimulating factor 1 receptor (CSF1R). Upon withdrawal of CSF1R inhibitors, microglia rapidly repopulate the entire brain, leading to replacement of the microglial compartment. In this study, we investigated the impact of microglial replacement in the aged brain on neural injury using a mouse model of intracerebral hemorrhage (ICH) induced by collagenase injection. We found that replacement of microglia in the aged brain reduced neurological deficits and brain edema after ICH. Microglial replacement-induced attenuation of ICH injury was accompanied with alleviated blood-brain barrier disruption and leukocyte infiltration. Notably, newly repopulated microglia had reduced expression of IL-1ß, TNF-α and CD86, and upregulation of CD206 in response to ICH. Our findings suggest that replacement of microglia in the aged brain restricts neuroinflammation and brain injury following ICH.


Aging/drug effects , Brain/drug effects , Cerebral Hemorrhage/drug therapy , Microglia/drug effects , Neuroinflammatory Diseases/drug therapy , Aging/pathology , Aminopyridines/administration & dosage , Aminopyridines/pharmacology , Animals , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/pathology , Brain/immunology , Brain/pathology , Brain Injuries/drug therapy , Brain Injuries/etiology , Brain Injuries/immunology , Brain Injuries/pathology , Cell Death/drug effects , Cerebral Hemorrhage/complications , Cerebral Hemorrhage/immunology , Cerebral Hemorrhage/pathology , Chemotaxis, Leukocyte/drug effects , Disease Models, Animal , Mice , Microglia/immunology , Microglia/pathology , Neuroinflammatory Diseases/etiology , Neuroinflammatory Diseases/immunology , Neuroinflammatory Diseases/pathology , Pyrroles/administration & dosage , Pyrroles/pharmacology , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors
9.
Int J Pharm ; 611: 121278, 2022 Jan 05.
Article En | MEDLINE | ID: mdl-34774693

Oral delivery of nanoparticles possesses many advantages for delivery of active pharmaceutical ingredients (APIs) to the gastrointestinal tract. However, the poor physical stability of nanoparticles in liquid state is often a challenge. Removing water from the nanosuspensions and transforming the nanoparticles into solid particulate matter in the form of, e.g., tablets could be a potential approach to increase the stability of nanoparticles. The aim of this study was to transform nanoparticles into compacts and to investigate the redispersion of nanoparticles from compacts as well as the dissolution behavior of these compacts. DL-lactide-co-glycolide copolymer (PLGA) nanoparticles and celecoxib (CLX) nanoparticles were used as two model nanoparticle systems and fabricated into nano-embedded microparticles (NEMs) and subsequently compressed into compacts. The compacts were evaluated with respect to the redispersibility of the nanoparticles, as well as the dissolution characteristics of CLX. The results showed that the NEMs could be readily compressed into compacts with sufficient mechanical strength. The size of the redispersed PLGA nanoparticles from the compacts using 2-hydroxypropyl-ß-cyclodextrin (HPßCD) as stabilizer was comparable to the original nanoparticles. In contrast, the redispersibility of CLX nanoparticles from the compacts was not as effective as for the PLGA nanoparticles evidenced by a significant increase in the size and polydispersity index (PDI) of the redispersed nanoparticles. Nonetheless, an obvious enhancement in dissolution rate of CLX was observed from the compacts with CLX nanoparticles. It is concluded that transforming polymeric nanoparticles into compacts via NEMs provides stabilization and allows redispersion into original nanoparticles. Despite the reduced redispersibility, compacts loaded with nanoparticles exhibited improved dissolution rate compared with the crystalline drug. Loading of nanoparticles into compacts is a promising approach to overcome the poor stability of nanoparticle within oral drug delivery of nanoparticles.


Nanoparticles , 2-Hydroxypropyl-beta-cyclodextrin , Celecoxib , Drug Delivery Systems , Polymers
10.
FASEB J ; 35(11): e21856, 2021 11.
Article En | MEDLINE | ID: mdl-34606651

Neuromyelitis optica spectrum disorder (NMOSD) is a severe central nervous system (CNS) autoimmune disease that primarily damages the optic nerves and spinal cord. Group 2 innate lymphoid cells (ILC2) are potent producers of type 2 cytokines that orchestrate immune and inflammatory responses. However, the role of ILC2 in CNS autoimmune diseases remains unknown. In patients with NMOSD, we identified a significant reduction of ILC2 in peripheral blood, which was correlated with disease severity. Using a mouse model of NMOSD induced by intracerebral injection of NMOSD-IgG with complement, we found CNS infiltration of ILC2 mainly expressing interleukin (IL)-5 and IL-13. The depletion of ILC2 led to increased CNS lesion volume, reduced CNS glucose metabolism, and augmented astrocyte injury and demyelination. The exacerbated NMOSD pathology was accompanied by increased accumulation of Iba1+ cells and complement activity in CNS lesions. In addition, the expansion of ILC2 using IL-33 attenuated NMO pathology. Collectively, these findings suggest a beneficial role of ILC2 in NMOSD, which deserves further investigation for future design of immune therapies to treat patients with NMOSD.


Immunity, Innate , Lymphocytes/immunology , Neuromyelitis Optica/immunology , Neuromyelitis Optica/pathology , Severity of Illness Index , Adult , Animals , Astrocytes/metabolism , Central Nervous System/immunology , Central Nervous System/metabolism , Complement System Proteins/metabolism , Disease Models, Animal , Female , Humans , Interleukin-33/administration & dosage , Interleukin-33/genetics , Male , Mice , Mice, Inbred C57BL , Middle Aged , Neuromyelitis Optica/blood , Neuromyelitis Optica/drug therapy , Recombinant Proteins/administration & dosage , Treatment Outcome
11.
Neuroreport ; 32(17): 1349-1356, 2021 12 08.
Article En | MEDLINE | ID: mdl-34718246

BACKGROUND: Intracerebral hemorrhage (ICH) is aggravated by immune cells that participate in the inflammatory response from the blood-brain barrier (BBB). O-Glycosylation has been reported to regulate the inflammatory response in the central nervous system but its cerebral protective effects remain unknown. Therefore, this study was carried out to investigate the protective effects of O-GlcNAcylation in a murine model of ICH and the possible mechanisms involved. METHODS: The effects of O-GlcNAcylation on hematoma and edema formation were tested using pathological and dry/wet weight methods, whereas its effects on neural function were determined using neurologic tests. The effect of O-GlcNAcylation on BBB integrity was determined by Evans blue dye extrusion. Flow cytometry was used to quantify the immune cells in the central nervous system. Immunofluorescence was used to detect the protective effect of O-GlcNAcylation in ICH. RESULTS: The hematoma volume was significantly lower in the prevention and treatment groups than in the control group after ICH induction, indicating that O-GlcNAcylation had reduced the formation of cerebral hematoma in ICH. In the prevention and treatment groups, the modified neurological severity score, corner turn test and rotating rod test results were improved and the BBB integrity was better than that in the control group. O-GlcNAcylation also regulated the microglia, neutrophils and other central nervous system immune cells after ICH, effectively reducing the inflammatory response. CONCLUSIONS: O-GlcNAcylation played an important role in suppressing the inflammatory response, enhancing the BBB integrity and reducing edema after ICH.


Blood-Brain Barrier/drug effects , Brain Edema/metabolism , Cerebral Hemorrhage/metabolism , Hematoma/metabolism , Neuroinflammatory Diseases/metabolism , Neuroprotective Agents/pharmacology , Pyrans/pharmacology , Thiazoles/pharmacology , beta-N-Acetylhexosaminidases/antagonists & inhibitors , Animals , B-Lymphocytes/drug effects , Behavior, Animal , Blood-Brain Barrier/metabolism , Brain Edema/physiopathology , CD4-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/drug effects , Cerebral Hemorrhage/physiopathology , Cytokines/drug effects , Cytokines/metabolism , Disease Models, Animal , Hematoma/physiopathology , Killer Cells, Natural/drug effects , Mice , Microglia/drug effects , Neuroinflammatory Diseases/physiopathology , Neutrophils/drug effects , Protein Processing, Post-Translational/drug effects , Rotarod Performance Test
12.
Sci Transl Med ; 13(605)2021 08 04.
Article En | MEDLINE | ID: mdl-34349037

Acute brain insults elicit pronounced inflammation that amplifies brain damage in intracerebral hemorrhage (ICH). We profiled perihematomal tissue from patients with ICH, generating a molecular landscape of the injured brain, and identified formyl peptide receptor 1 (FPR1) as the most abundantly increased damage-associated molecular pattern (DAMP) receptor, predominantly expressed by microglia. Circulating mitochondrial N-formyl peptides, endogenous ligands of FPR1, were augmented and correlated with the magnitude of brain edema in patients with ICH. Interactions of formyl peptides with FPR1 activated microglia, boosted neutrophil recruitment, and aggravated neurological deficits in two mouse models of ICH. We created an FPR1 antagonist T-0080 that can penetrate the brain and bind both human and murine FPR1. T-0080 attenuated brain edema and improved neurological outcomes in ICH models. Thus, FPR1 orchestrates brain inflammation after ICH and could be targeted to improve clinical outcome in patients.


Brain Injuries , Receptors, Formyl Peptide , Animals , Cerebral Hemorrhage , Humans , Inflammation , Mice , Neutrophil Infiltration , Signal Transduction
13.
FASEB J ; 35(6): e21617, 2021 06.
Article En | MEDLINE | ID: mdl-33982343

Intracerebral hemorrhage (ICH) is a severe stroke subtype without effective pharmacological treatment. Following ICH, peripheral leukocytes infiltrate into the brain and contribute to neuroinflammation and brain edema. However, the intercellular machinery controlling the initiation and propagation of leukocyte infiltration remains elusive. Exosomes are small extracellular vesicles released from donor cells and bridge intercellular communication. In this study, we investigated the effects of inhibition of exosome release on neuroinflammation and ICH injury. Using a mouse model of ICH induced by collagenase injection, we found that ICH induced an increase of exosome level in the brain. Inhibition of exosome release using GW4869 augmented neurological deficits and brain edema after ICH. The exacerbation of ICH injury was accompanied by increased barrier disruption and brain infiltration of leukocytes. The detrimental effects of GW4869 were ablated in ICH mice receiving antibody depletion of Gr-1+ myeloid cells. Extracted exosomes from the ICH brains suppressed the production of inflammatory factors by splenocytes. Additionally, exosomes extracted from brain tissues of donor ICH mice reduced ICH injury in recipient mice. These results demonstrate that inhibition of exosome release augments neuroinflammation and ICH injury. The impact of exosomes released from the ICH brain on the immune system deserves further investigation.


Brain/pathology , Cerebral Hemorrhage/complications , Exosomes/pathology , Inflammation/pathology , Neurons/pathology , Animals , Brain/metabolism , Cerebral Hemorrhage/chemically induced , Exosomes/metabolism , Inflammation/etiology , Inflammation/metabolism , Male , Mice , Mice, Inbred C57BL , Neurons/metabolism
14.
Drug Deliv ; 28(1): 206-217, 2021 Dec.
Article En | MEDLINE | ID: mdl-33472443

Corneal neovascularization (CNV) is the major cause of blindness after eye injury; however, only several drugs can be applied and the invasive administration ways (i.e., intravitreal injection and subconjunctival injection) are used. Resveratrol is a highly effective anti-VEGF agent against CNV. However, its applications are limited due to its strong hydrophobicity and instability. Here, we developed a resveratrol-loaded ocular lamellar crystalline gel (ROLG) for high inhibition of CNV. ROLGs were composed of resveratrol, glyceryl monooleate (GMO), ethanol, and water, and their lamellar crystalline structures were identified by polarizing light microscopy and small-angle X-ray scattering. High drug loading (4.4 mg/g) of ROLGs was achieved due to the hydrogen bonding between GMO and resveratrol. Resveratrol showed sustained release with 67% accumulative release in 7 h, which was attributed to the slow erosion of gels. Resveratrol in ROLGs had a high corneal permeation 3 times higher than resveratrol in hyaluronic acid suspensions (RHSs). ROLGs were administered to rats only once a day because of their strong retention on the cornea surface. ROLGs were safe due to the very little contact of ethanol in ROLGs to the cornea. CNV post-rat corneal alkaline injury was highly inhibited by ROLGs, resulting from the attenuation of corneal VEGF expression and then corneal healing was improved. The ROLG was a promising ocular medicine for the prevention of CNV.


Corneal Neovascularization/prevention & control , Enzyme Inhibitors/administration & dosage , Gels , Liquid Crystals , Resveratrol/administration & dosage , Vascular Endothelial Growth Factor A/drug effects , Wound Healing/drug effects , Administration, Ophthalmic , Animals , Burns, Chemical/metabolism , Burns, Chemical/pathology , Cell Line , Computer Simulation , Corneal Injuries/chemically induced , Corneal Injuries/metabolism , Corneal Injuries/pathology , Corneal Neovascularization/metabolism , Corneal Neovascularization/pathology , Crystallization , Delayed-Action Preparations , Drug Carriers , Drug Liberation , Enzyme Inhibitors/pharmacology , Epithelial Cells/drug effects , Epithelium, Corneal/cytology , Epithelium, Corneal/drug effects , Ethanol , Eye Burns/chemically induced , Eye Burns/metabolism , Eye Burns/pathology , Glycerides , Humans , In Vitro Techniques , Molecular Docking Simulation , Ocular Absorption , Powder Diffraction , Rats , Resveratrol/pharmacology , Scattering, Small Angle , Spectroscopy, Fourier Transform Infrared , Tomography, Optical Coherence , Vascular Endothelial Growth Factor A/metabolism , Water
15.
Front Cell Neurosci ; 14: 575690, 2020.
Article En | MEDLINE | ID: mdl-33343302

Background: Intracerebral hemorrhage (ICH) is a fatal subtype of stroke that lacks effective therapy. Blood-brain barrier (BBB) damage is a hallmark of ICH-induced brain injury that leads to edema formation, leukocytes infiltration, influx of blood components into the perihematomal (PHE) region, and eventually brain injury. Astrocytes are essential for the formation and maintenance of the BBB by providing secreted molecules that contribute to the association between these cells. Sonic hedgehog (SHH) derived from astrocytes promotes the maturity and integrity of the BBB by upregulating tight junctions (TJs) in brain capillary endothelial cells (ECs). However, the effect of SHH on BBB in ICH has not been investigated. Methods: Cyclopamine (CYC) is a potent, selective inhibitor that specifically blocks the SHH signaling pathway. Here, we used pharmacological inhibitions (CYC and its derivatives) to determine a critical role of the SHH signaling pathway in promoting BBB integrity after ICH by mechanisms of regulating the TJ proteins in vivo and in vitro. Results: The expression of astrocytic SHH was upregulated in mouse brains after ICH. Compared with the vehicle-treated group, inhibition of the SHH signaling pathway with CYC and its derivatives treatments aggravated neurological function deficits, brain edema, hematoma volume, and BBB impairment by downregulating TJs in ECs through the SHH-Gli-1 axis in vivo and in vitro. Conclusions: SHH signaling pathway at the level of the BBB provides a barrier-promoting effect, suggesting that the SHH signaling pathway may function as a potential therapeutic target for restoring BBB function in ICH.

16.
J Exp Med ; 217(12)2020 12 07.
Article En | MEDLINE | ID: mdl-32870258

Perihematomal edema (PHE) occurs within hours after intracerebral hemorrhage (ICH), leading to secondary injury manifested by impaired blood-brain barrier (BBB) integrity and destruction of adjacent tissue. To dissect the mechanisms underlying PHE formation, we profiled human and mouse perihematomal tissues and identified natural killer (NK) cells as the predominant immune cell subset that outnumbers other infiltrating immune cell types during early stages of ICH. Unbiased clustering of single-cell transcriptional profiles revealed two major NK cell subsets that respectively possess high cytotoxicity or robust chemokine production features in the brain after ICH, distinguishing them from NK cells of the periphery. NK cells exacerbate BBB disruption and brain edema after ICH via cytotoxicity toward cerebral endothelial cells and recruitment of neutrophils that augment focal inflammation. Thus, brain-bound NK cells acquire new features that contribute to PHE formation and neurological deterioration following ICH.


Brain Edema/etiology , Brain/pathology , Cerebral Hemorrhage/complications , Disease Progression , Killer Cells, Natural/immunology , Animals , Antibodies, Monoclonal/immunology , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/pathology , Brain Edema/immunology , Cerebral Hemorrhage/immunology , Chemokine CXCL2/metabolism , Disease Models, Animal , Endothelial Cells/drug effects , Endothelial Cells/pathology , Female , Humans , Inflammation/pathology , Killer Cells, Natural/drug effects , Male , Mice, Inbred C57BL , Poly I-C/pharmacology , Transcriptome/genetics
17.
Front Cell Neurosci ; 14: 154, 2020.
Article En | MEDLINE | ID: mdl-32655370

Background: Non-alcoholic fatty liver disease (NAFLD) is a common liver condition characterized by a significant accumulation of lipids in the liver without excessive alcohol consumption. Accumulating evidence suggests a significantly increased risk of intracerebral hemorrhage (ICH) in NAFLD patients. However, it remains poorly understood whether and how NAFLD affects the outcome of hemorrhagic brain injury. Here, we examined the effects of diet-induce NAFLD on ICH injury and neuroinflammation in mice. Methods: NAFLD was induced in C57BL/6 mice by feeding with a methionine-choline deficient (MCD) diet for 4 weeks. Collagenase and autologous blood models were used to evaluate the effects of NAFLD on ICH injury and neuroinflammation. Results: MCD diet for 4 weeks induces NAFLD and hyperlipidemia in mice. Mice receiving the MCD diet have aggravated neurological deficits and brain edema after ICH. The augmentation of ICH injury was accompanied by brain infiltration of neutrophils and monocytes and increased production of pro-inflammatory factors. Before ICH, MCD diet-induced mobilization of neutrophils and monocytes in the periphery. Notably, the detrimental effects of NAFLD on ICH injury was ablated in mice receiving antibody depletion of neutrophils and monocytes. Conclusions: These results suggest that NAFLD exacerbates neuroinflammation and ICH injury.

18.
Front Immunol ; 11: 759, 2020.
Article En | MEDLINE | ID: mdl-32477329

Brain ischemia induces systemic immunosuppression and increases a host's susceptibility to infection. MicroRNAs (miRNAs) are molecular switches in immune cells, but the alterations of miRNAs in human immune cells in response to brain ischemia and their impact on immune defense remain elusive. Natural killer (NK) cells are critical for early host defenses against pathogens. In this study, we identified reduced counts, cytokine production, and cytotoxicity in human peripheral blood NK cells obtained from patients with acute ischemic stroke. The extent of NK cell loss of number and activity was associated with infarct volume. MicroRNA sequencing analysis revealed that brain ischemia significantly altered miRNA expression profiles in circulating NK cells, in which miRNA-451a and miRNA-122-5p were dramatically upregulated. Importantly, inhibition of miR-451a or miR-122-5p augmented the expression of activation-associated receptors in NK cells. These results provide the first evidence that brain ischemia alters miRNA signatures in human NK cells.


Brain Ischemia/metabolism , Ischemic Stroke/metabolism , Killer Cells, Natural/metabolism , MicroRNAs/metabolism , Adult , Aged , Aged, 80 and over , Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , Cohort Studies , Gene Expression Profiling , Healthy Volunteers , Humans , Lectins, C-Type/metabolism , Leukocytes, Mononuclear , MicroRNAs/genetics , Middle Aged , NK Cell Lectin-Like Receptor Subfamily K/metabolism
19.
Acta Biomater ; 112: 87-100, 2020 08.
Article En | MEDLINE | ID: mdl-32450231

Amifostine is a cytoprotective agent against the hematopoietic damage induced by ionizing radiation, although the intravenous injection of amifostine is a unique administration method with strict dosing time limitation. Hence, the fields of application of amifostine are greatly limited. Here, we developed an amifostine-loaded armored microneedle (AAMN) with long-term prevention of hematopoietic injury induced by ionizing radiation. First, amifostine-loaded hyaluronic acid microneedles (AMNs) were fabricated, and the AMNs were then dipped in an N-vinyl-2-pyrrolidone (NVP) solution followed by ultraviolet (UV) photocuring to obtain AAMNs. AAMNs were nail-shaped with much higher mechanical strength compared to the conical shape and weak strength of AMNs, which was verified by their in silico simulation. In the in vitro release experiment, more than 55% of amifostine was released from AAMNs within 10 min, and 95% was released in 60 min. Drug skin permeation of AAMNs was also high, at twice that of AMNs. AAMNs provided long-term protection of the hematopoietic system from radiation within 3-7 h pre-radiation compared to the unique amifostine injection 0.5 h pre-radiation because topical application of AAMNs led to the long-term maintenance of the in vivo effective drug concentration. More importantly, AAMNs led to the survival of all irradiated mice due to intravenous amifostine. AAMNs are a promising transdermal delivery system of amifostine for long-term protection against ionizing radiation-induced injury. STATEMENT OF SIGNIFICANCE: An amifostine-loaded dissolving armored microneedle (AAMN) patch is developed for long-term prevention of ionizing radiation-induced injury. High drug loads in microneedles (MNs) with adequate mechanical strength is a challenge. We fabricated armors on the surface of high amifostine-loaded hyaluronic acid microneedles (AMNs) by dipping the tips of AMNs in N-vinyl-2-pyrrolidone (NVP) solutions and then subjecting them to UV irradiation, and high-strength armored AMNs (AAMNs) were obtained. AAMNs show deeper skin insertion and much higher drug permeation than AMNs. The controlled drug release from AAMNs in the mouse skins provides a long-term protection of radiation-induced injury with 3-7 h administration pre-radiation compared to the merely 0.5-h point of amifostine injection.


Amifostine , Administration, Cutaneous , Animals , Mice , Needles , Radiation, Ionizing , Transdermal Patch
20.
Biomolecules ; 9(12)2019 12 04.
Article En | MEDLINE | ID: mdl-31817275

Experimental autoimmune encephalomyelitis (EAE) is attenuated in nicotinic acetylcholine receptor (nAChR) α9 subunit knock-out (α9 KO) mice. However, protection is incomplete, raising questions about roles for related, nAChR α10 subunits in ionotropic or recently-revealed metabotropic contributions to effects. Here, we demonstrate reduced EAE severity and delayed onset of disease signs in nAChR α9/α10 subunit double knock-out (DKO) animals relative to effects in wild-type (WT) control mice. These effects are indistinguishable from contemporaneously-observed effects in nicotine-treated WT or in α9 KO mice. Immune cell infiltration into the spinal cord and brain, reactive oxygen species levels in vivo, and demyelination, mostly in the spinal cord, are reduced in DKO mice. Disease severity is not altered relative to WT controls in mice harboring a gain-of-function mutation in α9 subunits. These findings minimize the likelihood that additional deletion of nAChR α10 subunits impacts disease differently than α9 KO alone, whether through ionotropic, metabotropic, or alternative mechanisms. Moreover, our results provide further evidence of disease-exacerbating roles for nAChR containing α9 subunits (α9*-nAChR) in EAE inflammatory and autoimmune responses. This supports our hypothesis that α9*-nAChR or their downstream mediators are attractive targets for attenuation of inflammation and autoimmunity.


Encephalomyelitis, Autoimmune, Experimental/genetics , Receptors, Nicotinic/genetics , Animals , Encephalomyelitis, Autoimmune, Experimental/metabolism , Female , Gain of Function Mutation , Male , Mice , Mice, Knockout , Reactive Oxygen Species/metabolism , Severity of Illness Index
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