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1.
Nanotechnology ; 2024 May 06.
Article En | MEDLINE | ID: mdl-38710176

Electrochromic polymers (ECPs) have great application potential in flexible displays, and there is an increasing expectation of using green methods to form ECP films. Herein, we propose a modified microemulsion method to prepare Cyan/Magenta/Yellow (C/M/Y) water-dispersed electrochromic polymer nanoparticles systems. Three polymer films (WDECP-C/M/Y) maintain similar electrochemical properties compared to their corresponding organic solvent-based polymer films. It is intriguing that WDECP-C/M/Y exhibit better electrochromic properties in terms of higher cycling stability (97.24%, 95.05%, and 52.84%, respectively) and faster switching time (0.94 s, 1.09 s, and 1.34 s for coloring time, respectively) due to the introduction of nanoparticles. In addition, it can achieve various desired colors by blending the C/M/Y water-dispersed electrochromic polymer nanoparticles systems in different ratios. The calculated chromaticity coordinates of the blending polymer films show close values to the experimental observation, and the calculated ΔE*ab values range from 2.6 to 10.3, which may provide theoretical guidance for precisely color control. Finally, large-scale and patterned devices were assembled, which can achieve colored-to-colorless reversible electrochromism at a low driving voltage of 0 to 1.5 V. This work puts forward a universal and environmentally sustainable strategy to prepare water-dispersed electrochromic polymer nanoparticles systems, demonstrating their wide range of applications in display devices and electronic tags.

2.
Macromol Rapid Commun ; : e2400031, 2024 Apr 15.
Article En | MEDLINE | ID: mdl-38620002

The systematic study of two ionic porous organic polymers (iPOPs) based on viologens and their first applications in the electrochromic field are reported. The viologen-based iPOPs are synthesized by electrochemical polymerization with cyano groups, providing a simple and controllable method for iPOPs that solves the film preparation problems common to viologens. After the characterization of these iPOPs, a detailed study of their electrochromic properties is conducted. The iPOP films based on viologens structure exhibit excellent electrochromic properties. In addition, the resulting iPOP films show high sensitivity to electrolyte ions of different sizes in the redox process. Electrochemical and electrochromic data of the iPOPs explain this phenomenon in detail. These results demonstrate that iPOPs of this type are ideal candidates as electrochromic materials due to their inherent porous structures and ion-rich properties.

3.
Mol Biol Rep ; 51(1): 558, 2024 Apr 20.
Article En | MEDLINE | ID: mdl-38643323

BACKGROUND: Our previous research shows that Curcumin (CUR) attenuates myocardial ischemia-reperfusion injury (MIRI) by reducing intracellular total RNA m6A levels. However, the mechanism remains unknown. METHODS: For ischemia-reperfusion (IR), H9c2 cells were cultured for 6 h in serum-free low-glycemic (1 g/L) medium and a gas environment without oxygen, and then cultured for 6 h in high-glycemic (4.5 g/L) medium supplemented with 10% FBS and a 21% oxygen environment. The effects of different concentrations of CUR (5, 10, and 20 µM) treatments on signaling molecules in conventionally cultured and IR-treated H9c2 cells were examined. RESULTS: CUR treatment significantly up-regulated the H2S levels, and the mRNA and protein expression of cystathionine γ-lyase (CSE), and down-regulated the mRNAs and proteins levels of thiosulfate sulfurtransferase (TST) and ethylmalonic encephalopathy 1 (ETHE1) in H9c2 cells conventionally cultured and subjected to IR. Exogenous H2S supply (NaHS and GYY4137) significantly reduced intracellular total RNA m6A levels, and the expression of RNA m6A "writers" METTL3 and METTL14, and increased the expression of RNA m6A "eraser" FTO in H9c2 cells conventionally cultured and subjected to IR. CSE knockdown counteracted the inhibitory effect of CUR treatment on ROS production, promotion on cell viability, and inhibition on apoptosis of H9c2 cells subjected to IR. CONCLUSION: CUR attenuates MIRI by regulating the expression of H2S level-regulating enzymes and increasing the endogenous H2S levels. Increased H2S levels could regulate the m6A-related proteins expression and intracellular total RNA m6A levels.


Curcumin , Hydrogen Sulfide , Myocardial Reperfusion Injury , Humans , Myocardial Reperfusion Injury/drug therapy , Myocardial Reperfusion Injury/metabolism , Curcumin/pharmacology , Hydrogen Sulfide/pharmacology , Hydrogen Sulfide/metabolism , RNA , Oxygen/metabolism , Methyltransferases/metabolism , Mitochondrial Proteins/metabolism , Nucleocytoplasmic Transport Proteins , Alpha-Ketoglutarate-Dependent Dioxygenase FTO
4.
Vet Sci ; 11(4)2024 Apr 15.
Article En | MEDLINE | ID: mdl-38668443

Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) play key roles in regulating testosterone secretion and spermatogenesis in male mammals, respectively, and they maintain the fertility of male animals by binding to their corresponding receptors. We designed and prepared a recombinant LH receptor (LHR) subunit vaccine and a recombinant FSH receptor (FSHR) subunit vaccine and used male Sprague Dawley (SD) rats as a model to examine their effects on testicular development, spermatogenesis, and testosterone secretion in prepubertal and pubertal mammals. Both vaccines (LHR-DTT and FSHR-DTT) significantly decreased the serum testosterone level in prepubertal rats (p < 0.05) but had no effect on the testosterone secretion in pubertal rats; both vaccines decreased the number of cell layers in the seminiferous tubules and reduced spermatogenesis in prepubertal and pubertal rats. Subunit vaccine FSHR-DTT decreased the sperm density in the epididymis in both prepubertal and pubertal rats (p < 0.01) and lowered testicular index and sperm motility in pubertal rats (p < 0.05), whereas LHR-DTT only reduced the sperm density in the epididymis in pubertal rats (p < 0.05). These results indicate that the FSHR subunit vaccine may be a promising approach for immunocastration, but it still needs improvements in effectiveness.

5.
PLoS One ; 19(4): e0302407, 2024.
Article En | MEDLINE | ID: mdl-38640125

Xinnaotongluo liquid has been used to improve the clinical symptoms of patients with myocardial infarction. However, the molecular mechanism of Xinnaotongluo liquid is not completely understood. H9c2 cells exposed to hypoxia/reoxygenation (H/R) was used to simulate damage to cardiomyocytes in myocardial infarction in vitro. The biological indicators of H9c2 cells were measured by cell counting kit-8, enzyme linked immunoabsorbent assay, and western blot assay. In H/R-induced H9c2 cells, a markedly reduced murine double minute 2 (MDM2) was observed. However, the addition of Xinnaotongluo liquid increased MDM2 expression in H/R-induced H9c2 cells. And MDM2 overexpression strengthened the beneficial effects of Xinnaotongluo liquid on H9c2 cells from the perspective of alleviating oxidative damage, cellular inflammation, apoptosis and ferroptosis of H/R-induced H9c2 cells. Moreover, MDM2 overexpression reduced the protein expression of p53 and Six-Transmembrane Epithelial Antigen of Prostate 3 (STEAP3). Whereas, STEAP3 overexpression hindered the function of MDM2-overexpression in H/R-induced H9c2 cells. Our results insinuated that Xinnaotongluo liquid could protect H9c2 cells from H/R-induced damage by regulating MDM2/STEAP3, which provide a potential theoretical basis for further explaining the working mechanism of Xinnaotongluo liquid.


Drugs, Chinese Herbal , Hypoxia , Myocardial Infarction , Animals , Male , Apoptosis/drug effects , Cell Hypoxia , Hypoxia/drug therapy , Hypoxia/metabolism , Myocardial Infarction/drug therapy , Myocardial Infarction/metabolism , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Proto-Oncogene Proteins c-mdm2/genetics , Proto-Oncogene Proteins c-mdm2/metabolism , Rats , Drugs, Chinese Herbal/pharmacology
6.
Int J Mol Sci ; 25(6)2024 Mar 15.
Article En | MEDLINE | ID: mdl-38542311

Blast-induced neurotrauma (BINT) is a pressing concern for veterans and civilians exposed to explosive devices. Affected personnel may have increased risk for long-term cognitive decline and developing tauopathies including Alzheimer's disease-related disorders (ADRD) or frontal-temporal dementia (FTD). The goal of this study was to identify the effect of BINT on molecular networks and their modulation by mutant tau in transgenic (Tg) mice overexpressing the human tau P301L mutation (rTg4510) linked to FTD or non-carriers. The primary focus was on the phosphoproteome because of the prominent role of hyperphosphorylation in neurological disorders. Discrimination learning was assessed following injury in the subsequent 6 weeks, using the automated home-cage monitoring CognitionWall platform. At 40 days post injury, label-free phosphoproteomics was used to evaluate molecular networks in the frontal cortex of mice. Utilizing a weighted peptide co-expression network analysis (WpCNA) approach, we identified phosphopeptide networks tied to associative learning and mossy-fiber pathways and those which predicted learning outcomes. Phosphorylation levels in these networks were inversely related to learning and linked to synaptic dysfunction, cognitive decline, and dementia including Atp6v1a and Itsn1. Low-intensity blast (LIB) selectively increased pSer262tau in rTg4510, a site implicated in initiating tauopathy. Additionally, individual and group level analyses identified the Arhgap33 phosphopeptide as an indicator of BINT-induced cognitive impairment predominantly in rTg4510 mice. This study unveils novel interactions between ADRD genetic susceptibility, BINT, and cognitive decline, thus identifying dysregulated pathways as targets in potential precision-medicine focused therapeutics to alleviate the disease burden among those affected by BINT.


Frontotemporal Dementia , Tauopathies , Mice , Humans , Animals , tau Proteins/genetics , tau Proteins/metabolism , Frontotemporal Dementia/genetics , Phosphopeptides , Tauopathies/metabolism , Mice, Transgenic , Cognition , Disease Models, Animal
7.
Article En | MEDLINE | ID: mdl-37957857

OBJECTIVE: Endothelial cells (ECs) can provide cell protection for cardiomyocytes (CMs) under hypoxia-reoxygenation (HR) conditions by secreting derived factors. This study aimed to explore the role of curcumin (CUR) in ECs for protecting CMs from HR injury. METHODS: A co-culture system for ECs and CMs was set up, and subjected to HR. The transcription, expression, and secretion of FGF2 were detected by RT-qPCR, western blot, and ELISA, respectively. siRNAs specifically targeting FGF2 were transfected into ECs. FGF2 receptor- specific inhibitors (AZD4547) were used to treat CMs. RESULTS: The co-culture with ECs did not affect the proliferation of CMs, while CUR and ECs co-culture had a synergistic effect on promoting the proliferation of CMs in HR. Furthermore, the co-culture with ECs did not affect the apoptosis and autophagy of CMs in HR. However, the co-culture of ECs after CUR treatment inhibited the apoptosis and autophagy of CMs in HR. CUR treatment significantly enhanced FGF2 mRNA, protein, and secretion levels of ECs in HR. In addition, CUR treatment increased FGF2 levels in the CMs medium in the ECs and CMs co-culture system. The reduction of FGF2 levels in the medium and the inhibition of FGF2 receptors significantly inhibited the proliferation of CMs and significantly promoted the apoptosis and autophagy of CMs in HR. CONCLUSION: Focusing on the protective effects of CUR and ECs on cardiomyocytes is of great significance for the treatment of clinical myocardial HR injury.

8.
ACS Appl Mater Interfaces ; 15(46): 53984-53995, 2023 Nov 22.
Article En | MEDLINE | ID: mdl-37934922

This work presents a new strategy to achieve a truly black electrochromic film and develop available intelligent eye-protection filters with "day mode" and "night mode", promising to minimize the harmful effects of light on eyes. The soluble red-to-transparent electrochromic polymer P1 was constructed using quinacridone as the basic unit and introduced dual-donor proDOT and DTC units with similar electron-donating capabilities. The beneficial broader absorption associated with the dual-donor in P1 results in ideal spectrum complementarity with P2 (cyan-to-transparent) in the visible region (380-780 nm). In addition to complementary colors, both polymers exhibit good compatibility with respect to electrochemical and electrochromic properties. Therefore, a P1/P2 film with a mass ratio of 1:1.5 for blending is preferred to obtain truly black color with fast switching time and good cyclic stability. Furthermore, an electrochromic device for intelligent eye-protection filters was designed and assembled with the P1/P2 film as the electrochromic layer and P3 featuring a yellow (antiblue ray)-to-dark gray color change as the ion storage layer. The assembled prototype electrochromic device demonstrated promising applications in intelligent day-night optical adjustment for eye-protection filters.

9.
Acta Neuropathol Commun ; 11(1): 144, 2023 09 06.
Article En | MEDLINE | ID: mdl-37674234

Mild traumatic brain injury (mTBI) induced by low-intensity blast (LIB) is a serious health problem affecting military service members and veterans. Our previous reports using a single open-field LIB mouse model showed the absence of gross microscopic damage or necrosis in the brain, while transmission electron microscopy (TEM) identified ultrastructural abnormalities of myelin sheaths, mitochondria, and synapses. The neurovascular unit (NVU), an anatomical and functional system with multiple components, is vital for the regulation of cerebral blood flow and cellular interactions. In this study, we delineated ultrastructural abnormalities affecting the NVU in mice with LIB exposure quantitatively and qualitatively. Luminal constrictive irregularities were identified at 7 days post-injury (DPI) followed by dilation at 30 DPI along with degeneration of pericytes. Quantitative proteomic analysis identified significantly altered vasomotor-related proteins at 24 h post-injury. Endothelial cell, basement membrane and astrocyte end-foot swellings, as well as vacuole formations, occurred in LIB-exposed mice, indicating cellular edema. Structural abnormalities of tight junctions and astrocyte end-foot detachment from basement membranes were also noted. These ultrastructural findings demonstrate that LIB induces multiple-component NVU damage. Prevention of NVU damage may aid in identifying therapeutic targets to mitigate the effects of primary brain blast injury.


Blast Injuries , Brain Concussion , Brain Injuries , Animals , Mice , Proteomics , Arvicolinae , Basement Membrane
10.
J Histochem Cytochem ; 71(9): 481-493, 2023 09.
Article En | MEDLINE | ID: mdl-37599425

Gelatin zymography is widely used to detect gelatinase activity, which is performed on unfixed tissue because it is assumed that fixation inactivates enzymes. However, using fixed tissues has several advantages over using fresh tissues for such prevention of tissue decay, thereby preserving the proteins as well as the morphology and structure of the specimens. In this study, we investigated the effects of the four commonly used fixatives (ethanol, acetone, zinc-based fixative (ZBF), and paraformaldehyde (PFA)) on the gelatinolytic activity in mouse brain tissue. Multiple protocols were employed to extract proteins from the fixed brain tissue. Western blotting and in-gel zymography (IGZ) were used to detect the gelatinase proteins and gelatinolytic activity of the extractions, respectively. In situ zymography (ISZ) revealed that ethanol, acetone, ZBF, and short-time PFA fixation did not inhibit gelatinolytic activity. Neither 1% Triton + 1 M NaCl nor 10% DMSO + 1 M NaCl was effective in extracting proteins from ethanol-, acetone-, ZBF-, or PFA-fixed brain tissues. However, 8 M urea + 4% CHAPS effectively extracted gelatinase proteins from ethanol- and acetone-fixed tissues while retaining the gelatinolytic activity. 2% SDS effectively extracted gelatinase proteins from ethanol-, acetone-, and ZBF-fixed tissues while retaining the gelatinolytic activity. Although 2% SDS + heating extracted gelatinase proteins from ethanol-, acetone-, ZBF-, and even long-term PFA-fixed tissues, the gelatinolytic activity was not retained. Our findings suggest that both ISZ and IGZ can be performed on fixed brain tissue, which is anticipated to be an improvement over the conventionally used gelatin zymography methods. (J Histochem Cytochem 71: 481-493, 2023).


Acetone , Gelatin , Animals , Mice , Sodium Chloride , Brain , Ethanol , Fixatives
11.
Small ; 19(45): e2303359, 2023 Nov.
Article En | MEDLINE | ID: mdl-37415549

This work presents a new strategy to achieve highly stable electrochromic devices and bilayer film construction. A novel solution-processable electrochromic polymer P1-Boc with quinacridone as the conjugated backbone and t-Boc as N-substituted non-conjugated solubilizing groups is designed. Thermal annealing of P1-Boc film results in the cleavage of t-Boc groups and the formation of N─H⋯O═C hydrogen-bonding crosslinked network, which changes its intrinsic solubility characteristics into a solvent-resistant P1 film. This film retains the electrochemical behavior and spectroelectrochemistry properties of the original P1-Boc film. Intriguingly, the electrochromic device based on the P1 film exhibits an ultrafast switching time (0.56/0.80 s at 523 nm) and robust electrochromic stability (retaining 88.4% of the initial optical contrast after 100 000 cycles). The observed cycle lifetime is one of the highest reported for all-organic electrochromic devices. In addition, a black-transparent bilayer electrochromic film P1/P2 is developed in which the use of the solvent-resistant P1 film as the bottom layer avoids interface erosion of the solution-processable polymer in a multilayer stacking.

12.
Comb Chem High Throughput Screen ; 26(10): 1848-1855, 2023.
Article En | MEDLINE | ID: mdl-36177634

OBJECTIVE: Myocardial ischemia-reperfusion (IR) injury is an unresolved medical problem with a high incidence. This study aims to analyze the novel molecular mechanism by which curcuminoids protect cardiomyocytes from IR injury. METHODS: A IR model In Vitro of rat cardiomyocytes H9c2 cells was structured. Curcumin (CUR) and its derivatives, demethoxycurcumin (DMC) and bisdemethoxycurcumin (BDMC) treated H9c2 cells, and reactive oxygen species (ROS) production, viability, apoptosis, mitochondrial membrane potential (MMP), oxidative stress and total RNA m6A levels of H9c2 cells were detected by using DCFH-DA stain, CCK-8, flow cytometry, Hoechst 33342 stain, TMRM stain, ELISA and RTqPCR. FB23 was used in rescue experiments. RESULTS: IR significantly increased ROS production, decreased cell viability, and induced apoptosis, MMP loss, and oxidative stress. In addition, IR induced an increase in total RNA m6A levels and changes in m6A-related proteins expression. CUR (10 µM), DMC (10 µM) and BDMC (10 µM), significantly inhibited IR-induced ROS production, apoptosis, MMP loss and oxidative stress, and enhanced cell viability. Furthermore, CUR, DMC and BDMC altered the expression pattern of m6A-related proteins and reduced IR-induced total m6A levels. There was no significant difference in the effects of the three. CUR's protective effect was partially reduced by FB23. CONCLUSION: Curcuminoids attenuate myocardial IR injury by regulating total RNA m6A levels.


Curcumin , Myocardial Reperfusion Injury , Rats , Animals , Diarylheptanoids/pharmacology , Diarylheptanoids/metabolism , Myocardial Reperfusion Injury/drug therapy , Myocardial Reperfusion Injury/metabolism , Reactive Oxygen Species/metabolism , Cell Line, Tumor , Curcumin/pharmacology , Apoptosis , RNA/metabolism , Myocytes, Cardiac/metabolism
13.
Neurotrauma Rep ; 3(1): 27-38, 2022.
Article En | MEDLINE | ID: mdl-35141713

Mild traumatic brain injury induced by low-intensity blast (LIB) exposure poses concerns in military personnel. Using an open-field, non-inertial blast model and assessments by conventional behavioral tests, our previous studies revealed early-phase anxiety-like behaviors in LIB-exposed mice. However, the impact of LIB upon long-term anxiety-like behaviors requires clarification. This study applied a highly sensitive automated home-cage monitoring (HCM) system, which minimized human intervention and environmental changes, to assess anxiety-like responses in mice 3 months after LIB exposure. Initial assessment of 72-h spontaneous activities in a natural cage condition over multiple light and dark phases showed altered sheltering behaviors. LIB-exposed mice exhibited a subtle, but significantly decreased, duration of short shelter visits as compared to sham controls. Other measured responses between LIB-exposed mice and sham controls were insignificant. When behavioral assessments were performed in a challenged condition using an aversive spotlight, LIB-exposed mice demonstrated a significantly higher frequency of movements of shorter distance and duration per movement. Taken together, these findings demonstrated the presence of chronic anxiety-like behaviors assessed by the HCM system under both natural and challenged conditions in mice occurring post-LIB exposure. This model thus provides a platform to test for screening and interventions on anxiety disorders occurring after LIB non-inertial brain injury.

14.
Neurobiol Dis ; 165: 105634, 2022 04.
Article En | MEDLINE | ID: mdl-35077822

Neurocognitive consequences of blast-induced traumatic brain injury (bTBI) pose significant concerns for military service members and veterans with the majority of "invisible injury." However, the underlying mechanism of such mild bTBI by low-intensity blast (LIB) exposure for long-term cognitive and mental deficits remains elusive. Our previous studies have shown that mice exposed to LIB result in nanoscale ultrastructural abnormalities in the absence of gross or apparent cellular damage in the brain. Here we tested the hypothesis that glutamatergic hyperexcitability may contribute to long-term learning deficits. Using brain slice electrophysiological recordings, we found an increase in averaged frequencies with a burst pattern of miniature excitatory postsynaptic currents (mEPSCs) in hippocampal CA3 neurons in LIB-exposed mice at 1- and 7-days post injury, which was blocked by a specific NMDA receptor antagonist AP5. In addition, cognitive function assessed at 3-months post LIB exposure by automated home-cage monitoring showed deficits in dynamic patterns of discrimination learning and cognitive flexibility in LIB-exposed mice. Collected hippocampal tissue was further processed for quantitative global-proteomic analysis. Advanced data-independent acquisition for quantitative tandem mass spectrometry analysis identified altered expression of proteins involved in synaptic plasticity and serine protease inhibitors in LIB-exposed mice. Some were correlated with the ability of discrimination learning and cognitive flexibility. These findings show that acute glutamatergic hyperexcitability in the hippocampus induced by LIB may contribute to long-term cognitive dysfunction and protein alterations. Studies using this military-relevant mouse model of mild bTBI provide valuable insights into developing a potential therapeutic strategy to ameliorate hyperexcitability-modulated LIB injuries.


Blast Injuries , Proteomics , Animals , Blast Injuries/complications , Blast Injuries/metabolism , Hippocampus/metabolism , Mice , Neuronal Plasticity , Serine Proteinase Inhibitors/metabolism
15.
J Vasc Res ; 58(5): 301-310, 2021.
Article En | MEDLINE | ID: mdl-34218226

Endothelial dysfunction plays a central role in the patho-genesis of diabetic vascular complications. 2,3,5,4'-tetra-hydroxystilbene-2-O-ß-D-glucoside (TSG), an active component extracted from the roots of Polygonum multiflorum Thunb, has been shown to have strong antioxidant and antiapoptotic activities. In the present study, we investigated the protective effect of TSG on apoptosis induced by high glucose in human umbilical vein endothelial cells (HUVECs) and the possible mechanisms. Our data demonstrated that TSG significantly reversed the high glucose-induced decrease in cell viability, suppressed high glucose-induced generation of intracellular reactive oxygen species (ROS), the activity of caspase-3, and decreased the percentage of apoptotic cells in a dose-dependent manner. In addition, we found that TSG not only increased the expression of Bcl-2, while decreasing Bax expression, but also activated phosphorylation of Akt and endothelial nitric oxide synthase (eNOS) with subsequent nitric oxide production and ultimately reduced high glucose-induced apoptosis. However, the antiapoptotic effects of TSG were abrogated by pretreatment of the cells with PI3K inhibitor (LY294002) or eNOS inhibitor NG-L-nitro-arginine methyl ester, respectively. These results suggest that TSG inhibits high glucose-induced apoptosis in HUVECs through inhibition of ROS production, activation of the PI3K/Akt/eNOS pathway, and upregulation of the Bcl-2/Bax ratio, and thus may demonstrate significant potential for preventing diabetic cardiovascular complications.


Apoptosis/drug effects , Glucose/toxicity , Glucosides/pharmacology , Human Umbilical Vein Endothelial Cells/drug effects , Nitric Oxide Synthase Type III/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Stilbenes/pharmacology , bcl-2-Associated X Protein/metabolism , Cells, Cultured , Human Umbilical Vein Endothelial Cells/enzymology , Human Umbilical Vein Endothelial Cells/pathology , Humans , Nitric Oxide/metabolism , Phosphorylation , Reactive Oxygen Species/metabolism , Signal Transduction
16.
Mil Med ; 186(Suppl 1): 601-609, 2021 01 25.
Article En | MEDLINE | ID: mdl-33499439

INTRODUCTION: Blast overpressure exposure, an important cause of traumatic brain injury (TBI), may occur during combat or military training. TBI, most commonly mild TBI, is considered a signature injury of recent combat in Iraq and Afghanistan. Low intensity primary blast-induced TBI (bTBI), caused by exposure to an explosive shock wave, commonly leaves no obvious physical external signs. Numerous studies have been conducted to understand its biological effects; however, the role of shock wave energy as related to bTBI remains poorly understood. This report combines shock wave analysis with established biological effects on the mouse brain to provide insights into the effects of shock wave physics as related to low intensity bTBI outcomes from both open-air and shock tube environments. METHODS: Shock wave peak pressure, rise time, positive phase duration, impulse, shock velocity, and particle velocity were measured using the Missouri open-air blast model from 16 blast experiments totaling 122 mice to quantify physical shock wave properties. Open-air shock waves were generated by detonating 350-g 1-m suspended Composition C-4 charges with targets on 1-m elevated stands at 2.15, 3, 4, and 7 m from the source. RESULTS: All mice sustained brain injury with no observable head movement, because of mice experiencing lower dynamic pressures than calculated in shock tubes. Impulse, pressure loading over time, was found to be directly related to bTBI severity and is a primary shock physics variable that relates to bTBI. DISCUSSION: The physical blast properties including shock wave peak pressure, rise time, positive phase duration, impulse, shock velocity, and particle velocity were examined using the Missouri open-air blast model in mice with associated neurobehavioral deficits. The blast-exposed mice sustained ultrastructural abnormalities in mitochondria, myelinated axons, and synapses, implicating that primary low intensity blast leads to nanoscale brain damage by providing the link to its pathogenesis. The velocity of the shock wave reflected back from the target stand was calculated from high-speed video and compared with that of the incident shock wave velocity. Peak incident pressure measured from high sample rate sensors was found to be within 1% of the velocity recorded by the high-speed camera, concluding that using sensors in or close to an animal brain can provide useful information regarding shock velocity within the brain, leading to more advanced knowledge between shock wave physics and tissue damage that leads to bTBIs.


Brain Injuries, Traumatic , Afghanistan , Animals , Disease Models, Animal , Iraq , Mice , Missouri , Physics
17.
Front Neurol ; 12: 818169, 2021.
Article En | MEDLINE | ID: mdl-35095749

Most traumatic brain injuries (TBIs) during military deployment or training are clinically "mild" and frequently caused by non-impact blast exposures. Experimental models were developed to reproduce the biological consequences of high-intensity blasts causing moderate to severe brain injuries. However, the pathophysiological mechanisms of low-intensity blast (LIB)-induced neurological deficits have been understudied. This review provides perspectives on primary blast-induced mild TBI models and discusses translational aspects of LIB exposures as defined by standardized physical parameters including overpressure, impulse, and shock wave velocity. Our mouse LIB-exposure model, which reproduces deployment-related scenarios of open-field blast (OFB), caused neurobehavioral changes, including reduced exploratory activities, elevated anxiety-like levels, impaired nesting behavior, and compromised spatial reference learning and memory. These functional impairments associate with subcellular and ultrastructural neuropathological changes, such as myelinated axonal damage, synaptic alterations, and mitochondrial abnormalities occurring in the absence of gross- or cellular damage. Biochemically, we observed dysfunctional mitochondrial pathways that led to elevated oxidative stress, impaired fission-fusion dynamics, diminished mitophagy, decreased oxidative phosphorylation, and compensated cell respiration-relevant enzyme activity. LIB also induced increased levels of total tau, phosphorylated tau, and amyloid ß peptide, suggesting initiation of signaling cascades leading to neurodegeneration. We also compare translational aspects of OFB findings to alternative blast injury models. By scoping relevant recent research findings, we provide recommendations for future preclinical studies to better reflect military-operational and clinical realities. Overall, better alignment of preclinical models with clinical observations and experience related to military injuries will facilitate development of more precise diagnosis, clinical evaluation, treatment, and rehabilitation.

18.
Neuromolecular Med ; 23(1): 118-129, 2021 03.
Article En | MEDLINE | ID: mdl-32926329

The abundance of docosahexaenoic acid (DHA) in phospholipids in the brain and retina has generated interest to search for its role in mediating neurological functions. Besides the source of many oxylipins with pro-resolving properties, DHA also undergoes peroxidation, producing 4-hydroxyhexenal (4-HHE), although its function remains elusive. Despite wide dietary consumption, whether supplementation of DHA may alter the peroxidation products and their relationship to phospholipid species in brain and other body organs have not been explored sufficiently. In this study, adult mice were administered a control or DHA-enriched diet for 3 weeks, and phospholipid species and peroxidation products were examined in brain, heart, and plasma. Results demonstrated that this dietary regimen increased (n-3) and decreased (n-6) species to different extent in all major phospholipid classes (PC, dPE, PE-pl, PI and PS) examined. Besides changes in phospholipid species, DHA-enriched diet also showed substantial increases in 4-HHE in brain, heart, and plasma. Among different brain regions, the hippocampus responded to the DHA-enriched diet showing significant increase in 4-HHE. Considering the pro- and anti-inflammatory pathways mediated by the (n-6) and (n-3) polyunsaturated fatty acids, unveiling the ability for DHA-enriched diet to alter phospholipid species and lipid peroxidation products in the brain and in different body organs may be an important step forward towards understanding the mechanism(s) for this (n-3) fatty acid on health and diseases.


Brain/drug effects , Dietary Supplements , Docosahexaenoic Acids/pharmacology , Heart/drug effects , Lipid Peroxidation/drug effects , Myocardium/metabolism , Phospholipids/metabolism , Aldehydes/metabolism , Animals , Brain/metabolism , Chromatography, Liquid , Docosahexaenoic Acids/administration & dosage , Male , Mice , Mice, Inbred C57BL , Organ Specificity , Oxidation-Reduction , Phospholipids/analysis , Plasma , Random Allocation , Tandem Mass Spectrometry
19.
Exp Ther Med ; 19(2): 1554-1559, 2020 Feb.
Article En | MEDLINE | ID: mdl-32010338

Garlic (Allium sativum) has been widely used for culinary and medicinal purposes. Aged garlic extract (AGE) and sulfur-containing compounds, including S-allylcysteine (SAC) are well documented botanical active components of garlic. AGE is prepared by the prolonged extraction of fresh garlic with aqueous ethanol and is considered a nutritional supplement with potential to promote human health. SAC is a water-soluble organosulfur compound and the most abundant component of AGE. Studies have demonstrated that both AGE and SAC can exert neuroprotective effects against neuroinflammation and neurodegeneration. Another bioactive component in AGE is N-α-(1-deoxy-D-fructos-1-yl)-L-arginine (FruArg) although less is known about the metabolic activity of this compound. The main aim of this review was to provide an undated overview of the neuroprotective perspectives of these active garlic components (AGE, SAC and FruArg). Of interest, our studies and those of others indicate that both AGE and FruArg are involved in the regulation of gene transcription and protein expression. AGE has been shown to reverse 67% of the transcriptome alteration induced by endotoxins-lipopolysaccharide (LPS), and FruArg has been shown to account for the protective effects by reversing 55% of genes altered in a cell-based neuroinflammation paradigm stimulated by LPS in murine BV-2 microglial cells. AGE and FruArg can alleviate neuroinflammatory responses through a variety of signaling pathways, such as Toll-like receptor and interleukin (IL)-6 signaling, as well as by upregulating the nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated oxidative stress pathways known to promote microglial resiliency against neuroinflammation and neurodegeneration. The capability of FruArg to pass through the blood-brain barrier further supports its potential as a therapeutic compound. In summary, these experimental results provide new insight into the understanding of the neuroprotective effects of garlic components in promoting brain resiliency for health benefits.

20.
Neuromolecular Med ; 22(2): 278-292, 2020 06.
Article En | MEDLINE | ID: mdl-31900786

Spinal cord injury (SCI) is a deliberating disorder with impairments in locomotor deficits and incapacitating sensory abnormalities. Harpagophytum procumbens (Hp) is a botanical widely used for treating inflammation and pain related to various inflammatory and musculoskeletal conditions. Using a modified rodent contusion model of SCI, we explored the effects of this botanical on locomotor function and responses to mechanical stimuli, and examined possible neurochemical changes associated with SCI-induced allodynia. Following spinal cord contusion at T10 level, Hp (300 mg/kg, p.o.) or vehicle (water) was administered daily starting 24 h post-surgery, and behavioral measurements made every-other day until sacrifice (Day 21). Hp treatment markedly ameliorated the contusion-induced decrease in locomotor function and increased sensitivity to mechanical stimuli. Determination of Iba1 expression in spinal cord tissues indicated microglial infiltration starting 3 days post-injury. SCI results in increased levels of 4-hydroxynonenal, an oxidative stress product and proalgesic, which was diminished at 7 days by treatment with Hp. SCI also enhanced antioxidant heme oxygenase-1 (HO-1) expression. Concurrent studies of cultured murine BV-2 microglial cells revealed that Hp suppressed oxidative/nitrosative stress and inflammatory responses, including production of nitric oxide and reactive oxygen species, phosphorylation of cytosolic phospholipases A2, and upregulation of the antioxidative stress pathway involving the nuclear factor erythroid 2-related factor 2 and HO-1. These results support the use of Hp for management of allodynia by providing resilience against the neuroinflammation and pain associated with SCI and other neuropathological conditions.


Harpagophytum/chemistry , Hyperalgesia/drug therapy , Oxidative Stress/drug effects , Phytotherapy , Plant Extracts/therapeutic use , Spinal Cord Injuries/complications , Aldehydes/metabolism , Animals , Drug Evaluation, Preclinical , Gene Expression Regulation/drug effects , Heme Oxygenase (Decyclizing)/biosynthesis , Heme Oxygenase (Decyclizing)/genetics , Hyperalgesia/etiology , Inflammation , Male , Mice , Motor Activity/drug effects , NF-E2-Related Factor 2/biosynthesis , NF-E2-Related Factor 2/genetics , Nitric Acid/metabolism , Plant Extracts/chemistry , Plant Extracts/pharmacology , Rats , Rats, Sprague-Dawley , Reactive Nitrogen Species/metabolism , Reactive Oxygen Species/metabolism , Single-Blind Method , Touch
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