Injury Model Research Articles

Regional variations in hyperpolarized 129Xe lung MRI: Insights from CSI-CSSR and CSSR in healthy and irradiated rat models.

To compare pulmonary function metrics obtained with hyperpolarized xenon-129 (HXe) MRS, using chemical shift saturation recovery (CSSR) and CSI-CSSR, in healthy rats and a rat model of radiation-induced lung injury. HXe-MR data were acquired in two healthy rats and one rat with radiation-induced lung injury using whole-lung spectroscopy and CSI-CSSR techniques. The CSI-CSSR acquisitions were performed with both fixed TE and variable TE. Apparent alveolar septal wall thickness, gas transfer dynamics, and regional lung function were quantified and compared across acquisition methods. Spectral analysis included alignment of dissolved-phase frequency spectra using the membrane resonance as reference, segmentation of gas-phase (GP) frequency distribution, and characterization of gas uptake in the vasculature. Complex GP line shapes were observed in rat lungs, necessitating pixel-wise CSI analysis and membrane resonance alignment for improved quantification. Notable differences in alveolar septal wall thickness, dissolved-phase GP ratios, and GP and red blood cell frequencies were found between acquisition techniques and lung conditions. CSI-CSSR provided unique insights into regional lung function, including the identification of distinct GP frequency zones potentially corresponding to different airway structures, and the ability to map relative xenon gas transport. Metrics from fixed-TE and variable-TE acquisitions usually differed by less than 10%, but the latter yielded a 20% SNR gain. HXe-MRS and CSI-CSSR techniques provide similar but not universally interchangeable insights into lung function, particularly in the presence of pathology.

Berberine ameliorates septic cardiomyopathy through protecting mitochondria and upregulating Notch1 signaling in cardiomyocytes

IntroductionSeptic cardiomyopathy (SCM) arises as a consequence of sepsis-associated cardiovascular dysfunction, for which there is currently no specific targeted therapy available. Previous studies have demonstrated the beneficial therapeutic effect of berberine (BBR) on SCM; however, the underlying mechanisms of action remain unclear. The objective of this is to elucidate how BBR alleviates SCM.MethodsSeptic cardiomyopathy rat model was established by performing cecal ligation and puncture (CLP), while a cardiomyocyte injury model was provoked in H9C2 cells using lipopolysaccharide (LPS). Cardiac function was assessed through echocardiography, and myocardial histopathology was examined with hematoxylin-eosin (HE) staining. Cardiomyocyte viability was determined through Cell Counting Kit-8 (CCK8) assay, and measurement of ATP levels was done with an ATP assay kit. Mitochondrial ultrastructure was observed using transmission electron microscopy. Real-time polymerase chain reaction (RT-PCR) and Western blotting were employed to analyze the expression of Notch1 signaling pathway components and downstream molecules in myocardial tissues and cells.ResultIn vivo, BBR markedly improved symptoms and cardiac function in SCM rats, leading to enhanced ATP content, and ameliorated mitochondrial structure. Additionally, BBR increased Notch1 protein expression in myocardial tissue of the rats. In vitro, BBR elevated the survival rates of H9C2 cell, improved mitochondrial morphology, and raised ATP levels. The mRNA expression of Notch1, Hes1, and Hes2, and Notch1 protein expression was upregulated by BBR. While these effects were reversed upon inhibiting the Notch1 signaling pathway.ConclusionBBR improves septic cardiomyopathy by modulating Notch1 signaling to protect myocardial mitochondria.

A study on Modeling and Simulation of Sports Training Injury Optimization from a Biomechanical Perspective

With the development of artificial intelligence technology today, sports training is one of the important ways to keep people healthy. Reasonable sports training can keep people happy, and can also improve the physical quality of athletes. However, because the intensity of sports training is greater than the physical endurance, it may lead to physical injury. The sports training injury model can collect the physical data of athletes, and simulate whether the actions that athletes want to practice are standard and correct through the collected data. If there are errors in the simulated exercise actions, the wrong exercise actions can be corrected in time, so as to reduce the incidence of sports injury accidents. The construction of the experimental model and the calculation and analysis process of the construction data are very complex, and the existing simulation models are difficult to achieve this, which has a significant impact on the subsequent development of the simulation model. In view of this phenomenon, this paper, on the basis of the sports training injury model, combined with the neural network method, conducted an effective research on the construction of the sports training injury model, and inspected the performance of the model by testing the accuracy of the evaluation of the injury risk level, the degree of sports training injury, and the accuracy of the evaluation of the prediction results of the sports training injury model. The experimental data shows that the maximum accuracy of the sports training injury model in the horizontal and vertical directions was 94.43% and 95.26% respectively, and the maximum accuracy of the single injury degree and the composite injury degree was 48.68% and 55.01% respectively, which had high accuracy and operational efficiency, and can effectively avoid the occurrence of training injury.

Lgr5+ intestinal stem cells are required for organoid survival after genotoxic injury.

Progenitors and mature cells can maintain the intestinal epithelium by dedifferentiation and facultative intestinal stem cell (fISC) function when active ISCs (aISCs) are lost to damage. Here, we modeled fISC activation in intestinal organoids with doxorubicin (DXR), a chemotherapeutic known to ablate Lgr5+ aISCs in vivo. Similar fISC gene activation was observed between organoids treated with low vs high DXR, despite significantly decreased survival at the higher dose. aISCs exhibit dose-dependent loss after DXR but survive at doses compatible with organoid survival. We ablated residual aISCs after DXR using a Lgr52A-DTR allele and observed that aISC survival of the initial genotoxic insult is required for organoid survival following DXR. These results suggest that while typical fISC genes are activated by DXR injury in organoids, functional stemness remains dependent on the aISC pool. Finally, we show that human intestinal organoids require higher doses of DXR to induce loss of survival and downregulation of LGR5. Our data establish a reproducible model of DXR injury in intestinal organoids and reveal differences in in vitro responses to an established in vivo damage modality.

A nanofibrous polycaprolactone/collagen neural guidance channel filled with sciatic allogeneic schwann cells and platelet-rich plasma for sciatic nerve repair.

Sciatic nerve damage, a common condition affecting approximately 2.8% of the US population, can lead to significant disability due to impaired nerve signal transmission, resulting in loss of sensation and motor function in the lower extremities. In this study, a neural guidance channel was developed by rolling a nanofibrous scaffold produced via electrospinning. The scaffold's microstructure, biocompatibility, biodegradation rate, porosity, mechanical properties, and hemocompatibility were evaluated. Platelet-rich plasma (PRP) activated with 30,000 allogeneic Schwann cells (SCs) was injected into the lumen of the channels following implantation into a rat model of sciatic nerve injury. Recovery of motor function, sensory function, and muscle re-innervation was assessed using the sciatic function index (SFI), hot plate latency time, and gastrocnemius muscle wet weight loss. Results showed mean hot plate latency times of Autograft: 7.03, PCL/collagen scaffolds loaded with PRP and SCs (PCLCOLPRPSCs): 8.34, polymer-only scaffolds (PCLCOL): 10.66, and untreated animals (Negative Control): 12.00. The mean SFI values at week eight were Autograft: -49.30, PCLCOLPRPSCs: -64.29, PCLCOL: -75.62, and Negative Control: -77.14. The PCLCOLPRPSCs group showed a more negative SFI compared to the Autograft group but performed better than both the PCLCOL and Negative Control groups. These findings suggest that the developed strategy enhanced sensory and functional recovery compared to the negative control and polymer-only scaffold groups.

Exploring the mechanism of sesamin for the treatment of PM2.5-induced cardiomyocyte damage based on transcriptomics, network pharmacology and experimental verification

IntroductionExposure to fine particulate matter (PM2.5) is known to be associated with cardiovascular diseases. Sesamin (Ses) is a natural phenolic compound found in sesame seeds and sesame oil. Ferroptosis is a novel mode of cell death characterised by iron-dependent lipid peroxidation. This study aims to explore whether PM2.5 can induce ferroptosis in H9C2 cells and to investigate the precise protective mechanism of Ses.MethodsBased on transcriptomic data, PM2.5 may induce ferroptosis in cardiomyocytes. The ferroptosis inducer erastin and ferroptosis inhibitor ferrostatin-1 (Fer-1) were used to illustrate the mechanisms involved in PM2.5-induced H9C2 cell injury. Using network pharmacology, the pharmacological mechanism and potential therapy targets of Ses were explored for the treatment of PM2.5-induced cardiomyocyte injury. H9C2 cells were cultured and pretreated with Fer-1 or different concentrations of Ses, and then cardiomyocyte injury model was established using erastin or PM2.5. Indicators of oxidative responses, including total superoxide dismutase, reduced glutathione, glutathione peroxidase and malondialdehyde, were measured. The expression levels of ferroptosis-related proteins were determined through Western blot analysis.ResultsResults demonstrate that PM2.5 induces ferroptosis in H9C2 cells and Ses exerts a protective effect by suppressing ACSL4-mediated ferroptosis.DiscussionOverall, these findings elucidate a novel mechanism by which Ses ameliorates the detrimental effects of PM2.5 on cardiomyocytes.

Most AOTL type A and type B thoracolumbar primary fracture line follow the mechanism of an imaging-based injury model.

Based on the phenomenon that most thoracolumbar primary fracture line passes the center of the pedicle, we proposed an injury mechanism model to evaluate. Consecutive patients with thoracolumbar fractures treated operatively between October 2019, and December 2020 were analyzed retrospectively. Demographic and spinal radiographical parameters were measured and recorded. Pedicle hyperintensity on T2-weighted sagittal MR images was labeled. We examined the relationship between the course of the line (Radius) connecting the center of the pedicle of the injured vertebra and the IAR and orientation of the thoracolumbar primary fracture line. A partial correlation test was calculated to find correlations between demographic and spinal radiographical parameters. Nonlinear regression analysis was run with the Radius as the dependent variable and the other spinal kyphosis parameters as the independent variables to verify this model. Ninety-seven patients with 104 thoracolumbar fractures were included in this study. Ninety-four (90.4%) thoracolumbar fractures showed a high signal on MRI T2 through the pedicle. Involvement of the center of the pedicle was distributed among most AOTL Type A and Type B thoracolumbar fractures. In total, 92.3% of primary vertebral fracture lines followed the Radius of the model (r2 = 0.940). We provide a simple and quantifiable spinal instantaneous injury mechanism model for thoracolumbar fractures. Specifically, most AOTL type A and B thoracolumbar primary fracture line conforms to this model.

Salvianolate injection ameliorates cardiomyopathy by regulating autophagic flux through miR-30a/becn1 axis in zebrafish.

Salvianolate is a compound mainly composed of salvia magnesium acetate, which is extracted from the Chinese herb Salvia miltiorrhiza. In recent years, salvianolate injection has been widely used in the treatment of cardiovascular diseases, but the mechanism of how it can alleviate cardiotoxicity remains unclear. The cardiac injury model was constructed by treatment with doxorubicin (Dox) or azithromycin (Azi) in zebrafish larvae. Heart phenotype, heart rate, and cardiomyocyte apoptosis were observed in the study. RNA-seq analysis was used to explore the underlying mechanism of salvianolate treatment. Moreover, cardiomyocyte autophagy was assessed by in situ imaging. In addition, the miR-30a/becn1 axis regulation by salvianolate was further investigated. Salvianolate treatment reduced the proportion of pericardial edema, recovered heart rate, and inhibited cardiomyocyte apoptosis in Dox/Azi-administered zebrafish larvae. Mechanistically, salvianolate regulated the lysosomal pathway and promoted autophagic flux in zebrafish cardiomyocytes. The expression level of becn1 was increased in Dox-induced myocardial tissue injury after salvianolate administration; overexpression of becn1 in cardiomyocytes alleviated the Dox/Azi-induced cardiac injury and promoted autophagic flux in cardiomyocytes, while becn1 knockdown blocked the effects of salvianolate. In addition, miR-30a, negatively regulated by salvianolate, partially inhibited the cardiac amelioration of salvianolate by targeting becn1directly. This study has proved that salvianolate reduces cardiomyopathy by regulating autophagic flux through the miR-30a/becn1 axis in zebrafish and is a potential drug for adjunctive Dox/Azi therapy.

HES1 revitalizes the functionality of aged adipose-derived stem cells by inhibiting the transcription of STAT1.

The effectiveness of adipose-derived stem cells (ADSCs) in therapy diminishes with age. It has been reported that transcription factors (TFs) play a crucial role in the aging and functionality of stem cells. Nevertheless, there is limited understanding regarding the involvement of TFs in the aging mechanism of ADSCs. RNA sequencing (RNA-seq) was utilized to discern the differentially expressed genes in ADSCs obtained from donors of varying ages. TFs exhibiting significant variations across age groups were identified and subsequently validated. ADSCs were manipulated to exhibit either enhanced expression or reduced levels of HES1 and STAT1 via lentivirus transfection and small interfering RNA (siRNA) techniques. The impact of these genetic alterations on ADSCs' proliferation, migration, and cellular senescence was assessed using EdU, transwell, and senescence-activated β-galactosidase (SA-β-gal) staining assays. The DNA sequences bound by HES1 were investigated through the CUT & Tag assay. Lastly, the therapeutic efficacy of aged ADSCs with HES1 overexpression was evaluated in skin injury model of male Sprague-Dawley rats. 678 genes showed differential expression between ADSCs obtained from young and old donors (Y-ADSCs and O-ADSCs), with 47 of these genes being TFs. Notably, the expression of the TF hairy and enhancer of split 1 (HES1) was notably reduced in ADSCs from old donors. Introducing HES1 overexpression in aged ADSCs resulted in improved cellular function and the suppression of cellular senescence, while reducing HES1 levels in young ADSCs had the opposite effect. Mechanistically, HES1 was found to interact with the promoter region of another TF, signal transducer and activator of transcription 1 (STAT1), to inhibit its transcription. Knocking down STAT1 could fully reverse the negative effects caused by decreased HES1 in ADSCs, leading to a reduction in the secretion of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-8. Ultimately, restoring HES1 expression in aged ADSCs demonstrated enhanced therapeutic potential in promoting skin wound healing. HES1 acts as an inhibitor of cellular senescence in the aging progression of ADSCs through the modulation of STAT1 expression, suggesting a promising avenue for rejuvenating senescent ADSCs and improving wound healing.

Targeting of ubiquitination and degradation of KLF15 by E3 ubiquitin ligase KBTBD7 regulates LPS-induced septic brain injury in microglia

Septic brain injury is a serious disease of the central nervous system that involves inflammation. Kelch repeat and BTB domain containing 7 (KBTBD7), an E3 ubiquitin ligase, is demonstrated to facilitate the pathological changes of various diseases, but its impact on septic brain injury is unclear. In this study, a rat model of septic brain injury was induced by cecal ligation and puncture (CLP). The neurobehavioral score and survival rate of CLP group were worse than those of sham group. In addition, CLP was found to evoke microglia activation, increase inflammation, induce the activation of NLRP3 inflammasome and NF-κB signaling pathway, and upregulate KBTBD7 expression. Immunofluorescence revealed strong positive KBTBD7 staining in CLP rat microglia. Furthermore, primary microglia were exposed to lipopolysaccharide (LPS) to explore the role and mechanism of KBTBD7. The results showed that KBTBD7 expression was increased in LPS-treated microglia. Knockdown of KBTBD7 markedly inhibited LPS-induced proinflammatory cytokine release, as well as the activation of NLRP3 inflammasome and NF-κB signaling pathway. The downstream molecular mechanism of KBTBD7 was then mined. Notably, co-immunoprecipitation (co-IP) results confirmed that KBTBD7 was a novel interacting protein of KLF transcription factor 15 (KLF15) and acted as an E3 ubiquitin ligase that catalyzed the ubiquitination degradation of KLF15 through the ubiquitin-proteasome system. Moreover, recovery experiment data suggested that KLF15 knockdown abolished the anti-inflammatory role of KBTBD7 knockdown in microglia, implying that KLF15 influenced the function of KBTBD7. Taken together, our results reveal a novel KBTBD7-KLF15 signal transduction pathway involved in septic brain injury and provide a potential therapeutic strategy for its treatment.

The trans-differentiation promotion of parietal epithelial cells by magnesium isoglycyrrhizinate to improve podocyte injury induced by high fructose consumption

BackgroundPodocytes have limited proliferative capacity, which leads to irreversible glomerular injury in diverse kidney diseases. Magnesium isoglycyrrhizinate (MgIG), a hepatoprotective agent in clinic, has been reported to improve glomerular podocyte injury. However, the underlying mechanism of MgIG in ameliorating podocyte injury remains unclear. PurposeGlomerular parietal epithelial cells (PECs) are recognized as podocyte progenitors and play a pivotal role in the recovery following glomerular injury. This work aims to investigate the protective mechanisms of MgIG in mitigating glomerular injury by promoting PEC trans-differentiation. Study DesignA rat model of progressive glomerular podocyte injury, and in vitro models using the primary podocytes and primary PECs, were established to further explore the pharmacological mechanism of MgIG. MethodsFour-week-old male Sprague-Dawley (SD) rats were fed a 10% fructose solution for 3, 6, 9 and 12 weeks to induce glomerular injury. The effect of MgIG on the progressive changes in podocytes and PECs, and the correlation between PEC density and podocyte loss, were analyzed. The mechanism of MgIG in triggering PEC trans-differentiation was investigated, by examining adenosine secretion in injured podocytes, as well as the expression of cluster of differentiation 44 (CD44), nephrin, adenosine receptor A2B (ARA2B) and glucocorticoid receptor (GR) in PECs were examined both in vivo and in vitro. ResultsRats fed a high fructose diet exhibited progressive changes in glomerular PECs, including increased cell density and a preference for trans-differentiation. A positive correlation was observed between PEC density and podocyte loss. Co-culture experiments demonstrated that extracellular adenosine accumulation in injured podocytes induced by high fructose exposure promoted PEC trans-differentiation via ARA2B. MgIG significantly improved podocyte injury and exhibited effects similar to dexamethasone on nephrin upregulation activation and CD44 inhibition. Moreover, the inhibitory effect of MgIG on PEC ARA2B activation was more effective than that of dexamethasone. The co-expression of paired box 2 (PAX2)+-Nephrin+ in glomeruli indicated that MgIG induced PEC trans-differentiation and podocyte regeneration in model rats. Accordingly, podocyte loss and increased urine albumin-to-creatinine ratio (UACR) were also alleviated. Moreover, MgIG, which acts as a GR agonist to activate GR, reversed the upregulation of CD44 and decreased ARA2B induced by tumor necrosis factor-α (TNF-α) in primary PECs. The siRNA interference experiment manifested that MgIG exhibited a more pronounced enhancement of GR upregulation, in contrast to ARA2B activation, to promote PEC trans-differentiation. ConclusionThis work reports for the first time that PECs respond to the accumulation of extracellular adenosine from injured podocytes via activating ARA2B and focuses on the role of adenosine and adenosine receptors in the trans-differentiation of PECs. Furthermore, this study provides the first evidence that MgIG may promote podocyte regeneration by enhancing PEC trans-differentiation through GR activation, providing a research basis for investigating the glucocorticoid-like activity of MgIG in ameliorating glomerular podocyte injury.

Discovery of phenazine derivatives as a new class of non-classical ferroptosis inhibitors and efficacy evaluation on a mouse model of liver injury

Ferroptosis is an iron-dependent regulated cell death, which has been implicated in the onset and progression of numerous diseases. Ferroptosis inhibitors are thought as potential agents for treating these related diseases. However, the majority of currently available ferroptosis inhibitors are antioxidants or iron chelators (called classical ferroptosis inhibitors), which might have potential risks of side effects during clinical use. Herein, we report the discovery of phenazine derivatives as a new class of non-classical ferroptosis inhibitors. Structure-activity relationship of these series compounds led to the discovery of the most active compound 13l with an EC50 value of 0.0007 μM. Mechanistically, 13l could inhibit NCOA4-mediated ferritinophagy, hence protecting cells from ferroptosis. Notably, in the acetaminophen-induced acute liver injury model, 13l showed an excellent therapeutic effect. Overall, this compound reported here could be a promising lead compound for drug discovery targeting ferroptosis.

Kaempferol alleviates myocardial ischemia injury by reducing oxidative stress via the HDAC3-mediated Nrf2 signaling pathway

IntroductionKaempferol (KAE) is a flavonoid found in various plants. Recent studies showed that high dietary intake of KAE was associated with a lower risk of myocardial infarction; however, the cardioprotective mechanism of KAE remains unknown. ObjectivesTo determine the effect of KAE on cardiac injury in isoproterenol (ISO)-induced rats and cobalt chloride (CoCl2)-treated cardiomyocytes, and the underlying mechanisms. MethodsMale rats were pretreated with different doses of KAE for 14 days, and then injected with ISO to induce myocardial ischemia injury. We also established a model of myocardial cell injury using rat H9c2 cardiomyocytes stimulated with CoCl2. ResultsWe found that KAE pretreatment significantly alleviated myocardial injury and improved cardiac function in ISO-injected rats. In addition, KAE reduced oxidative stress in rats with myocardial ischemia by decreasing malondialdehyde concentration and increasing superoxide dismutase activity, and protection of the myocardial mitochondrial structure. KAE also attenuated CoCl2-induced injuryof H9c2 cardiomyocytes via suppression ofoxidative stress. With regard to the mechanism, we found that KAE down-regulated HDAC3 expression and up-regulated Nrf2 expression in ISO-induced rats and CoCl2-stimulated cardiomyocytes. Incubation of cardiomyocytes with HDAC3-selective inhibitor RGFP966 augmented the protective effect of KAE and reduced oxidative stress. By contrast, HDAC3 overexpression by adenovirus attenuated the effect of KAE on oxidative stress compared with KAE treatment group. HDAC3 also regulated Nrf2 expression in the cardiomyocytes with RGFP966 or an adenovirus overexpressing HDAC3; but Nrf2 inhibition reduced the effect of KAE on ROS generation in CoCl2-induced cardiomyocytes. Immunoprecipitation assay showed that HDAC3 interacted with Nrf2 in cardiomyocytes. Further studies found that KAE increased the acetylation level of Nrf2, while HDAC3 overexpression decreased the acetylation of Nrf2 compared with KAE treatment group. ConclusionOur data show that KAE ameliorates cardiac injury by reducing oxidative stress via the HDAC3-mediated Nrf2 signaling pathway in cardiomyocytes.

Intramuscular injection of Bothrops jararaca venom provoked acute kidney injury (AKI): Underpinned by impaired renal filtration, Na+ handling, and tissue damage

Globally, about 2.5 million people are victims of snakebites annually. In Brazil, the most clinically relevant snake is the Bothrops jararaca. The symptoms of envenomation are acute inflammation at the bite site and bleeding disorders. Despite kidney failure being the main cause of death after envenomation, kidney damage is not completely understood, and there are no clinically representative in vivo models. This work aimed to characterize the acute kidney injury (AKI) induced by intramuscular injection (IM) of Bothrops jararaca (Bjc) venom in male Wistar rats. The control group received 0.9% saline solution. Three doses of venom (3.5, 6.0, and 8.0 mg/kg) were administered IM into the posterior region of the right knee. After the injection, the rats were kept in metabolic cages. The following parameters were analyzed after 24 h: the extent of muscle damage and kidney damage (urinary creatinine, proteinuria, plasma creatinine, and renal tissue histology). All rats presented a hemorrhagic lesion at the injection site in a dose-dependent manner. Biochemical parameters indicated kidney damage: plasma creatinine accumulation, decreased glomerular filtration rate, albuminuria and proteinuria, and disturbance in Na+ homeostasis. Histological analyses showed glomerular injury, tissue discontinuity more evident in the cortex and tubular dilatation, and collagen deposition. The decline in renal function and tissue damage indicated the occurrence of AKI. Therefore, a Bjc venom-induced in vivo model of renal injury has been established for future studies.

Diammonium glycyrrhizinate alleviates iron overload-induced liver injury in mice via regulating the gut-liver axis

BackgroundEvidence indicates a close association between iron overload (IO) and the pathogenesis of chronic liver diseases, highlighting the potential for interventions targeted at IO to impede or decelerate the progression of chronic liver diseases. Diammonium glycyrrhizinate (DG), the medicinal form of glycyrrhizic acid, a principal constituent of licorice, has been clinically employed as a hepatoprotective agent; however, its protective effect against IO-induced liver injury and underlying molecular mechanisms remain elusive. PurposeThe aim of the present study is to investigate the hepatoprotective effect of DG against IO-induced liver injury with a focus on the gut-liver axis. Study design and methodsAnimal models of IO-induced liver injury and DG treatment have been established in vivo. Iron deposition, liver injury, intestinal barrier damage, and liver inflammation were assessed in mice treated with iron dextran or DG. The microbiome composition in feces was analyzed using 16S rRNA full-length sequencing. Bile acids (BAs) profiles in feces were detected by UPLC-Q-TOF-MS technique, and the expression levels of receptors, enzymes or transporters involved in BAs metabolism were also determined. ResultsDG partially reduced the iron deposition and the levels of ferrous ion in the livers of mice with IO, thereby mitigating oxidative damage. DG also improved gut microbiota dysbiosis, repaired intestinal barrier damage, inhibited endotoxin translocation to the liver, and subsequently suppressed TLR4/NF-κB/NLRP3 pathway-mediated liver inflammation caused by IO. Moreover, DG modulated BAs metabolism disorder in IO mice, reducing the accumulation of BAs in the liver. ConclusionDG alleviates IO-induced liver injury in mice by regulating the gut-liver axis. This study provides novel insights into the underlying mechanisms through which DG ameliorates liver injury caused by IO.

Hepatoprotective effects of the xanthine oxidase inhibitor Febuxostat against thioacetamide-induced liver injury in rats: The role of the Nrf2/ HO-1 and TLR4/ NF-κB pathways

Experimental models of liver injury have been established utilizing thioacetamide (TAA), a classic liver toxic chemical that causes organ damage via oxidative stress and inflammatory induction. This study examined the impact of Febuxostat (a xanthine oxidase inhibitor; Febu, 10–15 mg/kg, orally) against TAA (500 mg/kg, i.p.) -induced liver injury in rats.Febu significantly attenuated TAA-induced alterations in liver function parameters, in addition to promoting hepatic antioxidant effects through a significant elevation of Heme-oxygenase-1(HO-1), nuclear factor erythroid 2-related factor2 (Nrf2), reduced glutathione (GSH) and superoxide dismutase (SOD) levels and reduction in hepatic malondialdehyde (MDA) content. Moreover, Febu improved the hepatic anti-inflammatory status by increasing the anti-inflammatory cytokine Interleukin (IL-10) level and reducing the levels of the pro-inflammatory cytokines (Nuclear factor kappa B (NF-κB), IL-1β, high-mobility group box1 (HMGB1), receptor for advanced glycation end products (RAGE), and toll-like receptor4 (TLR4) levels, in addition to suppressing the increased protein and mRNA expression levels of tumor necrosis factor alpha (TNF-α) and IL-6, hepatic expression of TNF-α and activated mitogen-activated protein kinases (p-JNK/p-p38 MAPK). Histopathologically, Febu markedly normalized TAA-induced alteration in liver sections. In conclusion, Febu, in a dose-dependent fashion, refines TAA-induced hepatotoxicity by enhancing antioxidant capabilities and decreasing inflammatory signals.

The Neuroprotective Mechanisms of PPAR-γ: Inhibition of Microglia-Mediated Neuroinflammation and Oxidative Stress in a Neonatal Mouse Model of Hypoxic-Ischemic White Matter Injury.

Neuroinflammation and oxidative stress, mediated by microglial activation, hinder the development of oligodendrocytes (OLs) and delay myelination in preterm infants, leading to white matter injury (WMI) and long-term neurodevelopmental sequelae. Peroxisome proliferator-activated receptor gamma (PPAR-γ) has been reported to inhibit inflammation and oxidative stress via modulating microglial polarization in various central nervous system diseases. However, the relationship between PPAR-γ and microglial polarization in neonatal WMI is not well understood. Therefore, this study aimed to elucidate the role and mechanisms of PPAR-γ in preterm infants affected by WMI. In this study, an invivo hypoxia-ischemia (HI) induced brain WMI neonatal mouse model was established. The mice were administered intraperitoneally with either RSGI or GW9662 to activate or inhibit PPAR-γ, respectively. Additionally, an invitro oxygen-glucose deprivation (OGD) cell model was established and pretreated with pcDNA 3.1-PPAR-γ or si-PPAR-γ to overexpress or silence PPAR-γ, respectively. The neuroprotective effects of PPAR-γ were investigated invivo. Firstly, open field test, novel object recognization test, and beam-walking test were employed to assess the effects of PPAR-γ on neurobehavioral recovery. Furthermore, assessment of OLs loss and OL-maturation disorder, the number of myelinated axons, myelin thickness, synaptic deficit, activation of microglia and astrocyte, and blood-brain barrier (BBB) were used to evaluate the effects of PPAR-γ on pathological repair. The mechanisms of PPAR-γ were explored both invivo and invitro. Assessment of microglia polarization, inflammatory mediators, reactive oxygen species (ROS), MDA, and antioxidant enzymes was used to evaluate the anti-inflammatory and antioxidative effects of PPAR-γ activation. An assessment of HMGB1/NF-κB and NRF2/KEAP1 signaling pathway was conducted to clarify the mechanisms by which PPAR-γ influences HI-induced WMI in neonatal mice. Activation of PPAR-γ using RSGI significantly mitigated BBB disruption, promoted M2 polarization of microglia, inhibited activation of microglia and astrocytes, promoted OLs development, and enhanced myelination in HI-induced WMI. Conversely, inhibition of PPAR-γ using GW9662 further exacerbated the pathologic hallmark of WMI. Neurobehavioral tests revealed that neurological deficits were ameliorated by RSGI, while further aggravated by GW91662. In addition, activation of PPAR-γ significantly alleviated neuroinflammation and oxidative stress by suppressing HMGB1/NF-κB signaling pathway and activating NRF2 signaling pathway both invivo and invitro. Conversely, inhibition of PPAR-γ further exacerbated HI or OGD-induced neuroinflammation, oxidative stress via modulation of the same signaling pathway. Our findings suggest that PPAR-γ regulates microglial activation/polarization as well as subsequent neuroinflammation/oxidative stress via the HMGB1/NF-κB and NRF2/KEAP1 signaling pathway, thereby contributing to neuroprotection and amelioration of HI-induced WMI in neonatal mice.

NASA’s Top Human System Research and Technology Needs for Mars

NASA is working with industry and international partners to return humans to the Moon and to eventually enable humans to explore Mars. Within NASA, several organizations work together to identify, prioritize, fund, execute, and operationalize the research and technology development (R&TD) that will be necessary to enable crew health and performance (CHP) during these future missions. These organizations include flight programs, the Health and Medical Technical Authority (HMTA), the Human Research Program, the Space Technology Mission Directorate, System Capability Leadership Teams, and other organizations, many of which existed for several years prior to the creation of the Moon-to-Mars (M2M) Program Office in 2023. A variety of constructs, vocabularies, and processes exist for managing risks and supporting strategic planning across these organizations. For example, M2M objectives, program risks, human system risks, human research gaps, capability gaps, and envisioned futures are all constructs currently used within NASA to identify and prioritize R&TD needs. These strategic planning constructs are evolving to allow M2M objectives and R&TD investments to be aligned and traced at a detailed level. A recognized need exists among stakeholder organizations to identify and communicate the highest CHP R&TD priorities in a unified and digestible way that addresses the perspectives of NASA’s CHP community. To achieve this, the HMTA arranged a series of discussions with representatives of NASA’s CHP community, during which the 8 highest priority CHP capabilities that will enable human missions to Mars, referred to as the “top human system capability needs for Mars”, were identified. The list includes Earth-independent human operations; Mars-duration food system; Mars-duration effects on human physiology; risk mitigations for vehicle atmospheres; computational injury and anthropometric models; exploration exercise countermeasures; individual variability in responses to spaceflight; and sensorimotor countermeasures. Existing tools and processes for strategic planning and risk management were evaluated, as well as the technical practicalities, cost, and schedule feasibility associated with potential R&TD investments in different capability need areas. This capability needs report is not owned by any one NASA organization and does not replace existing strategic or program planning processes; rather it aims to complement and inform them with a unified set of community generated priorities. These top capability needs will be re-evaluated periodically based on R&TD progress and the evolving M2M architecture.

Exosomes Derived from Antler Mesenchymal Stem Cells Promote Wound Healing by miR-21-5p/STAT3 Axis.

Deer antlers, unique among mammalian organs for their ability to regenerate annually without scar formation, provide an innovative model for regenerative medicine. This study explored the potential of exosomes derived from antler mesenchymal stem cells (AMSC-Exo) to enhance skin wound healing. We explored the proliferation, migration and angiogenesis effects of AMSC-Exo on HaCaT cells and HUVEC cells. To investigate the skin repairing effect of AMSC-Exo, we established a full-thickness skin injury mouse model. Then the skin thickness, the epidermis, collagen fibers, CD31 and collagen expressions were tested by H&E staining, Masson's trichrome staining and immunofluorescence experiments. MiRNA omics analysis was conducted to explore the mechanism of AMSC-Exo in skin repairing. AMSC-Exo stimulated the proliferation and migration of HaCaT cells, accelerated the migration and angiogenesis of HUVEC cells. In the mouse skin injury model, AMSC-Exo stimulated angiogenesis and regulated the extracellular matrix by facilitating the conversion of collagen type III to collagen type I, restoring epidermal thickness to normal state without aberrant hyperplasia. Notably, AMSC-Exo enhanced the quality of wound healing with increased vascularization and reduced scar formation. MiRNAs in AMSC-Exo, especially through the miR-21-5p/STAT3 signaling pathway, played a crucial role in these processes. This study underscores the efficacy of AMSC-Exo in treating skin wounds, suggesting a new approach for enhancing skin repair and regeneration.

Effectiveness of the injectable hyaluronic acid-based microparticles loaded with cannabidiol on rat sciatic nerve injury model

Effectiveness of the injectable hyaluronic acid-based microparticles loaded with cannabidiol on rat sciatic nerve injury model