Osr2 functions as a biomechanical checkpoint to aggravate CD8+ T cell exhaustion in tumor.

Alterations in extracellular matrix (ECM) architecture and stiffness represent hallmarks of cancer. Whether the biomechanical property of ECM impacts the functionality of tumor-reactive CD8+ T cells remains largely unknown. Here, we reveal that the transcription factor (TF) Osr2 integrates biomechanical signaling and facilitates the terminal exhaustion of tumor-reactive CD8+ T cells. Osr2 expression is selectively induced in the terminally exhausted tumor-specific CD8+ T cell subset by coupled T cell receptor (TCR) signaling and biomechanical stress mediated by the Piezo1/calcium/CREB axis. Consistently, depletion of Osr2 alleviates the exhaustion of tumor-specific CD8+ T cells or CAR-T cells, whereas forced Osr2 expression aggravates their exhaustion in solid tumor models. Mechanistically, Osr2 recruits HDAC3 to rewire the epigenetic program for suppressing cytotoxic gene expression and promoting CD8+ T cell exhaustion. Thus, our results unravel Osr2 functions as a biomechanical checkpoint to exacerbate CD8+ T cell exhaustion and could be targeted to potentiate cancer immunotherapy.

Influence of topology on the phase transition of a ferromagnetic metal.

The topological ferromagnet CoS2 exhibits an anhysteretic, weakly first-order transition at the Curie temperature of 119.8 K with a tricritical point µ0Htcp at 0.034 T. Magnetic symmetry and the mixing of majority and minority spin eg bands at a subband crossing just above the Fermi level produce a topological component of the magnetization that leads to a negative M3 term in the Landau free energy. The position of the Fermi level relative to the subband crossing is critical for controlling the order of the transition. Hole doping in Co0.89Fe0.11S2 drains the minority-spin eg pocket and results in a normal second-order phase transition. Electron doping in Co0.94Ni0.06S2 raises the Fermi level toward the subband gap, producing a strongly first-order transition with 15 K hysteresis. Our results demonstrate a relation between topological electronic structure and thermal hysteresis at the Curie point, which may help in the search for magnetocaloric materials.

Swine pseudorabies virus attenuated vaccine reprograms the kidney cancer tumor microenvironment and synergizes with PD-1 blockade.

The global incidence rate of kidney cancer (KC) has been steadily increasing over the past 30 years. With the aging global population, kidney cancer has become an escalating concern that necessitates vigilant surveillance. Nowadays, surgical intervention remains the optimal therapeutic approach for kidney cancer, while the availability of efficacious treatments for advanced tumors remains limited. Oncolytic viruses, an emerging form of immunotherapy, have demonstrated encouraging anti-neoplastic properties and are progressively garnering public acceptance. However, research on oncolytic viruses in kidney cancer is relatively limited. Furthermore, given the high complexity and heterogeneity of kidney cancer, it is crucial to identify an optimal oncolytic virus agent that is better suited for its treatment. The present study investigates the oncolytic activity of the Pseudorabies virus live attenuated vaccine (PRV-LAV) against KC. The findings clearly demonstrate that PRV-LAV exhibits robust oncolytic activity targeting KC cell lines. Furthermore, the therapeutic efficacy of PRV-LAV was confirmed in both a subcutaneous tumor-bearing nude mouse model and a syngeneic mouse model of KC. Combined RNA-seq analysis and flow cytometry revealed that PRV-LAV treatment substantially enhances the infiltration of a diverse range of lymphocytes, including T cells, B cells, macrophages, and NK cells. Additionally, PRV-LAV treatment enhances T cell activation and exerts antitumor effects. Importantly, the combination of PRV-LAV with anti-PD-1 antibodies, an approved drug for KC treatment, synergistically enhances the efficacy against KC. Overall, the discovery of PRV-LAV as an effective oncolytic virus holds significant importance for improving the treatment efficacy and survival rates of KC patients.

MCM6 promotes intrahepatic cholangiocarcinoma progression by upregulating E2F1 and enhancing epithelial-mesenchymal transition.

Minichromosome maintenance complex component 6 (MCM6), a member of the MCM family, plays a pivotal role in DNA replication initiation and genome duplication of proliferating cells. MCM6 is upregulated in multiple malignancies and is considered a novel diagnostic biomarker. However, the functional contributions and prognostic value of MCM6 in intrahepatic cholangiocarcinoma (ICC) remain unexplored. In this study, we investigated the molecular function of MCM6 in ICC. Data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO, GSE107943) indicated an upregulation of MCM6 in tumor tissues. Immunohistochemical analysis performed on 115 cases of ICC samples confirmed the upregulation of MCM6 and further suggested that a high level of MCM6 expression predicted shorter overall and disease-free survival in ICC patients. Functional studies suggested that MCM6 knockdown significantly suppressed cell viability, blocked cell cycle progression and inhibited metastasis, while the enhancement of MCM6 expression promoted the proliferation and migration of ICC cells both in vitro and in vivo. Mechanistically, Gene Set Enrichment Analysis (GSEA) suggested that the epithelial-mesenchymal transition (EMT) and E2F1-correlated genes were enriched in ICC tissues with high MCM6 expression. Further verification indicated that MCM6 promoted the EMT of ICC cells via upregulating E2F1. In addition, E2F1 knockdown partially blocked the pro-malignant effects of MCM6 overexpression. In summary, MCM6 was found to be a novel prognostic and predictive marker for ICC. MCM6 promoted ICC progression via activation of E2F1-mediated EMT.

Condensed tannin accretions specifically distributed in mesophyll cells of non-salt secretor mangroves help in salt tolerance.

MAIN CONCLUSION: Auto-fluorescent condensed tannins specifically accumulated in mesophyll cells of non-salt secretor mangroves are involved in the compartmentation of Na+ and osmotic regulation, contributing to their salt tolerance. Salinity is a major abiotic stress affecting the distribution and growth of mangrove plants. The salt exclusion mechanism from salt secretor mangrove leaves is quite known; however, salt management strategies in non-salt secretor leaves remain unclear. In this study, we reported the auto-fluorescent inclusions (AFIs) specifically accumulated in mesophyll cells (MCs) of four non-salt secretor mangroves but absent in three salt secretors. The AFIs increased with the leaf development under natural condition, and applied NaCl concentrations applied in the lab. The AFIs in MCs were isolated and identified as condensed tannin accretions (CTAs) using the dye dimethyl-amino-cinnamaldehyde (DMACA), specific for condensed tannin (CT), both in situ leaf cross sections and in the purified AFIs. Fluorescence microscopy and transmission electron microscope (TEM) analysis indicated that the CTAs originated from the inflated chloroplasts. The CTAs had an obvious membrane and could induce changes in shape and fluorescence intensity in hypotonic and hypertonic NaCl solutions, suggesting CTAs might have osmotic regulation ability and play an important role in the osmotic regulation in MCs. The purified CTAs were labeled by the fluorescent sodium-binding benzofuran isophthalate acetoxymethyl ester (SBFI-AM), confirming they were involved in the compartmentation of excess Na+ in MCs. This study provided a new view on the salt resistance-associated strategies in mangroves.

A Neutralizing Antibody Targeting gH Provides Potent Protection against EBV Challenge In Vivo.

Epstein-Barr virus (EBV) is an oncogenic herpesvirus that is associated with 200,000 new cases of cancer and 140,000 deaths annually. To date, there are no available vaccines or therapeutics for clinical usage. Recently, the viral heterodimer glycoprotein gH/gL has become a promising target for the development of prophylactic vaccines against EBV. Here, we developed the anti-gH antibody 6H2 and its chimeric version C6H2, which had full neutralizing activity in epithelial cells and partial neutralizing activity in B cells. C6H2 exhibited potent protection against lethal EBV challenge in a humanized mouse model. The cryo-electron microscopy (cryo-EM) structure further revealed that 6H2 recognized a previously unidentified epitope on gH/gL D-IV that is critical for viral attachment and subsequent membrane fusion with epithelial cells. Our results suggest that C6H2 is a promising candidate in the prevention of EBV-induced lymphoproliferative diseases (LPDs) and may inform the design of an EBV vaccine. IMPORTANCE Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus that establishes lifelong persistence and is related to multiple diseases, including cancers. Neutralizing antibodies (NAbs) have proven to be highly effective in preventing EBV infection and subsequent diseases. Here, we developed an anti-EBV-gH NAb, 6H2, which blocked EBV infection in vitro and in vivo. This 6H2 neutralizing epitope should be helpful to understand EBV infection mechanisms and guide the development of vaccines and therapeutics against EBV infection.

New Analysis Protocol for Stable Isotopes by a Standard Doping Method─An Example of Antimony.

The current analytical methods of stable antimony isotopes are cumbersome and not suitable for rock samples with low antimony content (<1 µg/g). In this study, we propose a new protocol for antimony isotopic analysis with a single column of AG50W-X8 resin and antimony standard doping. This method separates antimony effectively from matrices and then mixes it with the Sb standard. As Te does not affect the accuracy of antimony measurement when the Te/Sb ratio is low, we can obtain an accurate Sb isotope composition of the mixture. Then, we can calculate the antimony isotope composition of natural samples. The error propagation of the mixing and calculation processes was evaluated by the Monte Carlo method, and no significant error was found. The antimony isotope compositions were measured using a Thermo Fisher Scientific Neptune Plus multicollector-inductively coupled-mass spectrometry instrument. The instrumental mass bias of Sb isotopes was corrected with a standard-sample bracketing combined with a Sn internal normalization technique. Using the standard doping method, the measured δ123Sb values of standard solutions (Alfa, SPEX, GSB, and SCP) relative to NIST SRM 3102a were 0.02 ± 0.03‰ (2SD, N = 50), 0.29 ± 0.03‰ (2SD, N = 15), 0.24 ± 0.03‰ (2SD, N = 56), and 0.30 ± 0.03‰ (2SD, N = 15), respectively. The reproducibility for δ123Sb was better than 0.03‰ (2SD) throughout one year. This methodology has been testified by geological samples, yielding δ123Sb identical to the previously reported values. The actual Sb consumption for each sample test is as low as 5 ng. This standard doping method provides new insights into the analytical strategy of stable isotopes.

LncRNA CRNDE is involved in radiation resistance in hepatocellular carcinoma via modulating the SP1/PDK1 axis.

Hepatocellular carcinoma (HCC) is defined as a universal malignancy while radiation therapy is the effective treatment for it. This study validated the mechanism of long non-coding RNA (lncRNA) colorectal neoplasia differentially expressed gene (CRNDE) in radiation resistance in HCC. LncRNA CRNDE upregulation was detected in HCC cells. The radiation-resistant cell strains Huh7R and SNU-387R were established. After silencing lncRNA CRNDE, the cell colony formation ability, cell activity, apoptosis, cell cycles, and γ-H2AX positive rate in Huh7R and SNU-387R were detected. Silencing lncRNA CRNDE decreased the cell activity, colony formation ability, and cell number in the G2 phase and facilitated DNA damage and apoptosis. The binding relations of specificity protein 1 (SP1) with lncRNA CRNDE and 3-phosphoinositide dependent protein kinase 1 (PDK1) were verified. LncRNA CRNDE regulated PDK1 transcription by binding to transcription factor SP1. PDK1 overexpression partially reversed the inhibition of silencing lncRNA CRNDE on radiation resistance in HCC cells. The transplanted tumor mouse model was established and showed that silencing lncRNA CRNDE decreased tumor volume and weight and Ki67-positive cells in HCC mice in vivo. Collectively, lncRNA CRNDE was upregulated in HCC cells and promoted PDK1 transcription by binding to SP1, thus enhancing radiation resistance in HCC cells.

Therapeutic Effect of Rapamycin on TDP-43-Related Pathogenesis in Ischemic Stroke.

Stroke is a major cause of death and disability across the world, and its detrimental impact should not be underestimated. Therapies are available and effective for ischemic stroke (e.g., thrombolytic recanalization and mechanical thrombectomy); however, there are limitations to therapeutic interventions. Recanalization therapy has developed dramatically, while the use of adjunct neuroprotective agents as complementary therapies remains deficient. Pathological TAR DNA-binding protein (TDP-43) has been identified as a major component of insoluble aggregates in numerous neurodegenerative pathologies, including ALS, FTLD and Alzheimer's disease. Here, we show that increased pathological TDP-43 fractions accompanied by impaired mitochondrial function and increased gliosis were observed in an ischemic stroke rat model, suggesting a pathological role of TDP-43 in ischemic stroke. In ischemic rats administered rapamycin, the insoluble TDP-43 fraction was significantly decreased in the ischemic cortex region, accompanied by a recovery of mitochondrial function, the attenuation of cellular apoptosis, a reduction in infarct areas and improvements in motor defects. Accordingly, our results suggest that rapamycin provides neuroprotective benefits not only by ameliorating pathological TDP-43 levels, but also by reversing mitochondrial function and attenuating cell apoptosis in ischemic stroke.

Single-Stage Extraction Technique for Ce Stable Isotopes and Measurement by MC-ICP-MS.

The separation of Ce from other rare earth elements has not been well established because of their similar geochemical properties. In this study, we report a single-stage extraction technique to purify Ce from natural samples with Eichrom DGA resin. This method separates Ce effectively from matrices and interfering elements, such as Ba, La, and Nd. The Ce elution curve would not drift with different Ce loading masses and rock types. The Ce isotope compositions were measured using a Thermo Scientific Neptune Plus multicollector (MC)-inductively coupled plasma (ICP)-mass spectrometry (MS) instrument. The instrumental mass bias of Ce isotopes was corrected with a sample-standard bracketing combined with a Sm-doping method. The δ142Ce values of standard solutions (CDUT-Ce and JMC304) relative to National Institute of Standards and Technology SRM 3110 measured were +0.128 ± 0.028‰ (2SD, N = 30) and 0.005 ± 0.038‰ (2SD, N = 30), respectively. The reproducibility for δ142Ce was better than 0.040‰. The Ce isotopic compositions of nine United States Geological Survey standard rocks, including carbonatite, basalt, andesite, quartz latite, dolerite, rhyolite, and granodiorite, were measured in this study. Our result showed that δ142Ce values of these rocks varied slightly, indicating that insignificant fractionation occurred during igneous processes. The technique proposed in this study is simple and time-efficient, which is beneficial for further studies on Ce isotope geochemistry.

Single probe PCR melting curve analysis MTHFR C677T SNP sites.

BACKGROUND: The detection and analysis of methylene tetrahydrofolate reductase (MTHFR) C677T single nucleotide polymorphism (SNP) from blood samples is time-consuming and costly. We aimed to establish a method to detect these SNPs by direct whole blood PCR and without DNA extraction. METHODS: Probes modified by different fluorescent groups on the same sequence were designed. Various MTHFR genotypes from direct blood PCR experiments were used to verify the similarity of the obtained and sequencing results. The SNP sites adjacent to the MTHFR C677T SNP were used to verify whether the method can accurately distinguish these sites. RESULTS: The ROX probe was found to be the most suitable for this study. We tested 291 samples with 1 µL whole blood as a template, and obtained 126, 43, and 122 cases of C677C, C677T, and C677 C/T genotypes, respectively. The melting curve was consistent with the sequencing results. The detection limit was approximately 1000 white blood cells/µL. Through PCR and the melting curve method, the adjacent sites were accurately distinguished. CONCLUSION: We established a reliable, simple, rapid, and low-cost direct blood PCR method for the detection of MTHFR C677T SNPs. This could also be used as a potential diagnostic tool for a variety of diseases.

The distribution of hepatitis C virus infection in Shanghai, China: a time-spatial study.

BACKGROUND: Shanghai, as a pilot city of China to achieve the goal of eliminating hepatitis C, its strategy of allocating medical resources is a pressing problem to be solved. This study aims to infer the time-spatial clustering patterns of HCV-infected cases, and grasp the dynamic genotype distribution of HCV, thereby inform elimination strategies of HCV with efficacy and efficiency. METHODS: Reported HCV cases including their demographic information in Shanghai city from 2005 to 2018 were released from the National Infectious Disease Reporting Information System, population data at community scale, geographical layers of hospitals, communities and districts were gathered from former research. Blood samples of HCV-infected individuals were collected during 2014-2018 from 24 sentinel hospitals, HCV-antibody test, qualitative nucleic acid test and NS5B/5'UTR gene amplification were performed accordingly to determine the genotypes of the specimen. Furthermore, global and local spatial self-correlation analysis of both acute and chronic HCV infections were conducted at community scale year by year, then time-spatial clusters of acute and chronic HCV infections and HCV genotype distribution of specimen collected from sentinel hospitals by districts were mapped by using Arcmap10.1. RESULTS: A total of 2631 acute HCV cases and 15,063 chronic HCV cases were reported in Shanghai from 2005 to 2018, with a peak in 2010 and 2017, respectively. The mean age of chronic HCV patients was 49.70 ± 14.55 years, 3.34 ± 0.32 years older than the acute (t = 10.55, P-value < 0.01). The spatial distribution of acute HCV infection formed one primary cluster (Relative Risk = 2.71), and the chronic formed one primary cluster and three secondary clusters with Relative Risk ranged from 1.94 to 14.42, meanwhile, an overlap of 34 communities between acute and chronic HCV clusters were found with time period spans varied from 6 to 12 years. Genotype 1 (N = 257, 49.71%) was the most prevalent HCV genotype in Shanghai, genotype 3 infections have increased in recent years. Baoshan district presented cluster of acute HCV and the highest proportion of genotype 2, Pudong new area was the cluster of chronic HCV and occupied the highest proportion of genotype 3. CONCLUSIONS: Despite the low prevalence of HCV infection, it is still needed to push forward the elimination process in Shanghai, as there is a certain amount of HCV infected people waiting to be treated. The time-spatial clustering patterns and the dynamic of HCV genotype distribution together indicated a changing constitution of different transmission routes of HCV infection, thus, a focused strategy may be needed for high-risk population related to genotype 3 infection like drug users, in addition to an enforcement of the existing measures of preventing the iatrogenic and hematogenic transmission of HCV.

Increased short- and long-term risk of sleep disorders in people with traumatic brain injury.

This study aims to evaluate the relationship between traumatic brain injury (TBI) and sleep disorders (SDs). We first initiated a questionnaire-based clinical survey to assess sleep problems in the early stage after a TBI, followed by a population-based cohort study to evaluate the long-term risk of SDs in TBI patients. For short-term clinical survey, mild (m)TBI patients and healthy controls were recruited to evaluate the sleep quality and daytime sleepiness using the Pittsburg Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS) within two weeks after a TBI. For long-term observation, a 5-year nationwide population-based cohort study that utilized a large administrative database was conducted. In the short-term survey, 236 mTBI patients and 223 controls were analyzed. Total scores of the PSQI and ESS were significantly higher in mTBI patients than in the controls. In the long-term cohort study, 6932 TBI cases and 34,660 matched controls were included. TBI cases had a 1.36-fold greater risk of SDs compared to the non-TBI controls during the 5-year follow-up period. Results showed that patients with TBI had a significantly higher risk of SDs than did controls both in the early stage and during a 5-year follow-up period.

Mesenchymal Stem/Stromal Cell Therapy in Blood-Brain Barrier Preservation Following Ischemia: Molecular Mechanisms and Prospects.

Ischemic stroke is the leading cause of mortality and long-term disability worldwide. Disruption of the blood-brain barrier (BBB) is a prominent pathophysiological mechanism, responsible for a series of subsequent inflammatory cascades that exacerbate the damage to brain tissue. However, the benefit of recanalization is limited in most patients because of the narrow therapeutic time window. Recently, mesenchymal stem cells (MSCs) have been assessed as excellent candidates for cell-based therapy in cerebral ischemia, including neuroinflammatory alleviation, angiogenesis and neurogenesis promotion through their paracrine actions. In addition, accumulating evidence on how MSC therapy preserves BBB integrity after stroke may open up novel therapeutic targets for treating cerebrovascular diseases. In this review, we focus on the molecular mechanisms of MSC-based therapy in the ischemia-induced prevention of BBB compromise. Currently, therapeutic effects of MSCs for stroke are primarily based on the fundamental pathogenesis of BBB breakdown, such as attenuating leukocyte infiltration, matrix metalloproteinase (MMP) regulation, antioxidant, anti-inflammation, stabilizing morphology and crosstalk between cellular components of the BBB. We also discuss prospective studies to improve the effectiveness of MSC therapy through enhanced migration into defined brain regions of stem cells. Targeted therapy is a promising new direction and is being prioritized for extensive research.

Genetically Modified Mesenchymal Stem Cells: The Next Generation of Stem Cell-Based Therapy for TBI.

Mesenchymal stem cells (MSCs) are emerging as an attractive approach for restorative medicine in central nervous system (CNS) diseases and injuries, such as traumatic brain injury (TBI), due to their relatively easy derivation and therapeutic effect following transplantation. However, the long-term survival of the grafted cells and therapeutic efficacy need improvement. Here, we review the recent application of MSCs in TBI treatment in preclinical models. We discuss the genetic modification approaches designed to enhance the therapeutic potency of MSCs for TBI treatment by improving their survival after transplantation, enhancing their homing abilities and overexpressing neuroprotective and neuroregenerative factors. We highlight the latest preclinical studies that have used genetically modified MSCs for TBI treatment. The recent developments in MSCs' biology and potential TBI therapeutic targets may sufficiently improve the genetic modification strategies for MSCs, potentially bringing effective MSC-based therapies for TBI treatment in humans.

Neuroprotective Effects of Emodin against Ischemia/Reperfusion Injury through Activating ERK-1/2 Signaling Pathway.

BACKGROUND: Stroke is one of the leading causes of death and disability worldwide and places a heavy burden on the economy in our society. Current treatments, such as the use of thrombolytic agents, are often limited by a narrow therapeutic time window. However, the regeneration of the brain after damage is still active days, even weeks, after stroke occurs, which might provide a second window for treatment. Emodin, a traditional Chinese medicinal herb widely used to treat acute hepatitis, has been reported to possess antioxidative capabilities and protective effects against myocardial ischemia/reperfusion injury. However, the underlying mechanisms and neuroprotective functions of Emodin in a rat middle cerebral artery occlusion (MCAO) model of ischemic stroke remain unknown. This study investigates neuroprotective effects of Emodin in ischemia both in vitro and in vivo. METHODS: PC12 cells were exposed to oxygen-glucose deprivation to simulate hypoxic injury, and the involved signaling pathways and results of Emodin treatment were evaluated. The therapeutic effects of Emodin in ischemia animals were further investigated. RESULTS: Emodin reduced infarct volume and cell death following focal cerebral ischemia injury. Emodin treatment restored PC12 cell viability and reduced reactive oxygen species (ROS) production and glutamate release under conditions of ischemia/hypoxia. Emodin increased Bcl-2 and glutamate transporter-1 (GLT-l) expression but suppressed activated-caspase 3 levels through activating the extracellular signal-regulated kinase (ERK)-1/2 signaling pathway. CONCLUSION: Emodin induced Bcl-2 and GLT-1 expression to inhibit neuronal apoptosis and ROS generation while reducing glutamate toxicity via the ERK-1/2 signaling pathway. Furthermore, Emodin alleviated nerve cell injury following ischemia/reperfusion in a rat MCAO model. Emodin has neuroprotective effects against ischemia/reperfusion injury both in vitro and in vivo, which may be through activating the ERK-1/2 signaling pathway.

The functional roles of IGF-1 variants in the susceptibility and clinical outcomes of mild traumatic brain injury.

BACKGROUND: Insulin-like growth factor 1 (IGF-1) is an important pleiotropic hormone that exerts neuroprotective and neuroreparative effects after a brain injury. However, the roles of IGF-1 variants in mild traumatic brain injury (mTBI) are not yet fully understood. This study attempted to elucidate the effects of IGF-1 variants on the risk and neuropsychiatric outcomes of mTBI. METHODS: Based on 176 recruited mTBI patients and 1517 control subjects from the Taiwan Biobank project, we first compared the genotypic distributions of IGF-1 variants between the two groups. Then, we analyzed associations of IGF-1 variants with neuropsychiatric symptoms after mTBI, including anxiety, depression, dizziness, and sleep disturbances. Functional annotation of IGF-1 variants was also performed through bioinformatics databases. RESULTS: The minor allele of rs7136446 was over-represented in mTBI patients compared to community-based control subjects. Patients carrying minor alleles of rs7136446 and rs972936 showed more dizziness and multiple neuropsychiatric symptoms after brain injury. CONCLUSIONS: IGF-1 variants were associated with the risk and neuropsychiatric symptoms of mTBI. The findings highlight the important role of IGF-1 in the susceptibility and clinical outcomes of mTBI.

Metabolic and proteomic mechanism of benzo[a]pyrene degradation by Brevibacillus brevis.

Benzo[a]pyrene (BaP) is a model compound of polycyclic aromatic hydrocarbons. The relationship between its toxicity and some target biomolecules has been investigated. To reveal the interactions of BaP biodegradation and metabolic network, BaP intermediates, proteome, carbon metabolism and ion transport were analyzed. The results show that 76% BaP was degraded by Brevibacillus brevis within 7 d through the cleavage of aromatic rings with the production of 1-naphthol and 2-naphthol. During this process, the expression of xylose isomerase was induced for xylose metabolism, whereas, α-cyclodextrin could no longer be metabolized. Lactic acid, acetic acid and oxalic acid at 0.1-1.2 mg dm-3 were released stemming from their enhanced biosynthesis in the pathways of pyruvate metabolism and citrate cycle, while 5-7 mg dm-3 of PO43- were transported for energy metabolism. The relative abundance of 43 proteins was significantly increased for pyruvate metabolism, citrate cycle, amino acid metabolism, purine metabolism, ribosome metabolism and protein synthesis.

Enhanced Homing of Mesenchymal Stem Cells Overexpressing Fibroblast Growth Factor 21 to Injury Site in a Mouse Model of Traumatic Brain Injury.

Mesenchymal stem cells (MSCs) are emerging as a potential therapeutic intervention for brain injury due to their neuroprotective effects and safe profile. However, the homing ability of MSCs to injury sites still needs to be improved. Fibroblast Growth Factor 21 (FGF21) was recently reported to enhance cells migration in different cells type. In this study, we investigated whether MSCs that overexpressing FGF21 (MSC-FGF21) could exhibit enhanced homing efficacy in brain injury. We used novel Molday IONEverGreen™ (MIEG) as cell labeling probe that enables a non-invasive, high-sensitive and real-time MRI tracking. Using a mouse model of traumatic brain injury (TBI), MIEG labeled MSCs were transplanted into the contralateral lateral ventricle followed by real-time MRI tracking. FGF21 retained MSC abilities of proliferation and morphology. MSC-FGF21 showed significantly greater migration in transwell assay compared to control MSC. MIEG labeling showed no effects on MSCs' viability, proliferation and differentiation. Magnetic resonance imaging (MRI) revealed that FGF21 significantly enhances the homing of MSC toward injury site. Histological analysis further confirmed the MRI findings. Taken together, these results show that FGF21 overexpression and MIEG labeling of MSC enhances their homing abilities and enables non-invasive real time tracking of the transplanted cells, provides a promising approach for MSC based therapy and tracking in TBI.

Nck2 is essential for limb trajectory selection by spinal motor axons.

BACKGROUND: The development of a functioning nervous system requires precise assembly of neuronal connections, which can be achieved by the guidance of axonal growth cones to their proper targets. How axons are guided by signals transmitted to the cytoskeleton through cell surface-expressed guidance receptors remains unclear. We investigated the function of Nck2 adaptor protein as an essential guidance intermediary in the context of spinal lateral motor column (LMC) motor axon trajectory into the limb. RESULTS: Nck2 mRNA and protein are preferentially expressed in the medial subgroups of chick LMC neurons during axon trajectory into the limb. Nck2 loss- and gain-of-function in LMC neurons using in ovo electroporation perturb LMC axon trajectory selection demonstrating an essential role of Nck2 in motor axon guidance. We also showed that Nck2 knockdown and overexpression perturb the growth preference of LMC neurites against ephrins in vitro and Eph-mediated redirection of LMC axons in vivo. Finally, the significant changes of LMC neurite growth preference against ephrins in the context of Nck2 and α2-chimaerin loss- and gain-of-function implicated Nck2 function to modulate α2-chimaerin activity. CONCLUSIONS: Here, we showed that Nck2 is required for Eph-mediated axon trajectory selection from spinal motor neurons through possible interaction with α2-chimaerin. Developmental Dynamics 247:1043-1056, 2018. © 2018 Wiley Periodicals, Inc.