Hsa_circ_0001535 inhibits the proliferation and migration of ovarian cancer by sponging miR-593-3p, upregulating PTEN expression

Background Hsa_circ_0001535 is involved in biological processes in various tumors. However, the biological effects and related mechanism of hsa_circ_0001535 in ovarian cancer (OC) is unclear. This work is aimed to probe the biological function and underlying mechanism of hsa_circ_0001535 in OC, especially sponged with mi-RNA, require further elucidation. Methods Hsa_circ_0001535 expression in OC tissues and cell lines were examined by qRT-PCR. Hsa_circ_0001535 overexpression model was constructed by lentivirus-mediated transfection in two OC cell lines, and the biological functions of hsa_circ_0001535 were evaluated by CCK-8, transwell assay and Western blot. Dual luciferase reporter gene assay was respectively used to explore the relationship between hsa_circ_0001535 and miR-593-3p, as well as miR-593-3p and PTEN. The expression of miR-593-3p and PTEN were detected by qRT-PCR in two OC cell lines and OC tissues. Results Hsa_circ_0001535 was down-regulated in OC tissues and cell lines. Hsa_circ_0001535 overexpression inhibited proliferation, migration and EMT marker expression in OC cells. Of interest, hsa_circ_0001535 targeted miR-593-3p and reduced its RNA level in OC cells. PTEN was a target gene of miR-593-3p, which was up-regulated by inhibiting miR-593-3p in OC cells. Furthermore, miR-593-3p mimic treatment reversed the up-regulation of PTEN by hsa_circ_0001535 overexpression in OC cells. Conclusions The above results showed that hsa_circ_0001535 acted as a molecular sponge for miR-593-3p to repress miR-593-3p expression, and promoted the expression of PTEN, thus inhibited proliferation and migration of OC cells. Our research provides a potential therapeutic target for ovarian cancer patients (AU)

Mature human induced pluripotent stem cell-derived cardiomyocytes promote angiogenesis through alpha-B crystallin.

BACKGROUND: Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) can be used to treat heart diseases; however, the optimal maturity of hiPSC-CMs for effective regenerative medicine remains unclear. We aimed to investigate the benefits of long-term cultured mature hiPSC-CMs in injured rat hearts. METHODS: Cardiomyocytes were differentiated from hiPSCs via monolayer culturing, and the cells were harvested on day 28 or 56 (D28-CMs or D56-CMs, respectively) after differentiation. We transplanted D28-CMs or D56-CMs into the hearts of rat myocardial infarction models and examined cell retention and engraftment via in vivo bioluminescence imaging and histological analysis. We performed transcriptomic sequencing analysis to elucidate the genetic profiles before and after hiPSC-CM transplantation. RESULTS: Upregulated expression of mature sarcomere genes in vitro was observed in D56-CMs compared with D28-CMs. In vivo bioluminescence imaging studies revealed increased bioluminescence intensity of D56-CMs at 8 and 12 weeks post-transplantation. Histological and immunohistochemical analyses showed that D56-CMs promoted engraftment and maturation in the graft area at 12 weeks post-transplantation. Notably, D56-CMs consistently promoted microvessel formation in the graft area from 1 to 12 weeks post-transplantation. Transcriptomic sequencing analysis revealed that compared with the engrafted D28-CMs, the engrafted D56-CMs enriched genes related to blood vessel regulation at 12 weeks post-transplantation. As shown by transcriptomic and western blot analyses, the expression of a small heat shock protein, alpha-B crystallin (CRYAB), was significantly upregulated in D56-CMs compared with D28-CMs. Endothelial cell migration was inhibited by small interfering RNA-mediated knockdown of CRYAB when co-cultured with D56-CMs in vitro. Furthermore, CRYAB overexpression enhanced angiogenesis in the D28-CM grafts at 4 weeks post-transplantation. CONCLUSIONS: Long-term cultured mature hiPSC-CMs promoted engraftment, maturation and angiogenesis post-transplantation in infarcted rat hearts. CRYAB, which was highly expressed in D56-CMs, was identified as an angiogenic factor from mature hiPSC-CMs. This study revealed the benefits of long-term culture, which may enhance the therapeutic potential of hiPSC-CMs.

Vitamin A Promotes the Repair of Mice Skeletal Muscle Injury through RARα.

Vitamin A (VitA) is an important fat-soluble vitamin which plays an important role in cell growth and individual development. However, the effect of VitA on the repair process of muscle injury and its molecular mechanism are still unclear. In this study, VitA and RA were first added to the culture medium of differentiated cells. We then detected cell differentiation marker proteins and myotube fusion. Moreover, the effects of VitA on RARα expression and nuclear translocation were further examined. The results showed that VitA significantly promoted the differentiation of C2C12, and the expression of RARα was significantly increased. Furthermore, VitA was injected into skeletal muscle injury in mice. HE staining and Western Blot results showed that VitA could significantly accelerate the repair of skeletal muscle injury and VitA increase the expression of RARα in mice. This study provides a theoretical basis for elucidating the regulation mechanism of VitA-mediated muscle development and the development of therapeutic drugs for muscle diseases in animals.

SaeR as a novel target for antivirulence therapy against Staphylococcus aureus.

Staphylococcus aureus is a major human pathogen responsible for a wide range of clinical infections. SaeRS is one of the two-component systems in S. aureus that modulate multiple virulence factors. Although SaeR is required for S. aureus to develop an infection, inhibitors have not been reported. Using an in vivo knockdown method, we demonstrated that SaeR is targetable for the discovery of antivirulence agent. HR3744 was discovered through a high-throughput screening utilizing a GFP-Lux dual reporter system driven by saeP1 promoter. The antivirulence efficacy of HR3744 was tested using Western blot, Quantitative Polymerase Chain Reaction, leucotoxicity, and haemolysis tests. In electrophoresis mobility shift assay, HR3744 inhibited SaeR-DNA probe binding. WaterLOGSY-NMR test showed HR3744 directly interacted with SaeR's DNA-binding domain. When SaeR was deleted, HR3744 lost its antivirulence property, validating the target specificity. Virtual docking and mutagenesis were used to confirm the target's specificity. When Glu159 was changed to Asn, the bacteria developed resistance to HR3744. A structure-activity relationship study revealed that a molecule with a slight modification did not inhibit SaeR, indicating the selectivity of HR3744. Interestingly, we found that SAV13, an analogue of HR3744, was four times more potent than HR3744 and demonstrated identical antivirulence properties and target specificity. In a mouse bacteraemia model, both HR3744 and SAV13 exhibited in vivo effectiveness. Collectively, we identified the first SaeR inhibitor, which exhibited in vitro and in vivo antivirulence properties, and proved that SaeR could be a novel target for developing antivirulence drugs against S. aureus infections.

Inhibitor Library Screening of SH2 Domains Through Denaturation-Based Assays.

Screening of inhibitor libraries for candidate ligands is an important step in the drug discovery process. Thermal denaturation-based screening strategies are built on the premise that a protein-ligand complex has an altered stability profile compared to the protein alone. As such, these assays provide an accessible and rapid methodology for stratifying ligands that directly engage with the protein target of interest. Here, we describe three denaturation-based strategies for examining protein-inhibitor binding, in the context of SH2 domains. This includes conventional dye-based Thermal Shift Assays (TSA), nonconventional labeled ligand-based TSA, and Cellular Thermal Shift Assays (CETSA). Conventional dye-based TSA reports on the fluorescence of an external hydrophobic dye as it interacts with heat-exposed nonpolar protein surfaces as the temperature is incrementally increased. By contrast, nonconventional-labeled ligand TSA involves a fluorescence-tagged probe (phosphopeptide for SH2 domains) that is quenched as it dissociates from the protein during the denaturation process. CETSA involves monitoring the presence of the protein via Western blotting as the temperature is increased. In all three approaches, performing the assay in the presence of a candidate ligand can alter the melting profile of the protein. These assays offer primary screening tools to examine SH2 domain inhibitors libraries with varying chemical motifs, and a subset of the advantages and limitations of each approach is also discussed.

Identification of molecular subtypes and immune infiltration in endometriosis: a novel bioinformatics analysis and In vitro validation.

Introduction: Endometriosis is a worldwide gynacological diseases, affecting in 6-10% of women of reproductive age. The aim of this study was to investigate the gene network and potential signatures of immune infiltration in endometriosis. Methods: The expression profiles of GSE51981, GSE6364, and GSE7305 were obtained from the Gene Expression Omnibus (GEO) database. Core modules and central genes related to immune characteristics were identified using a weighted gene coexpression network analysis. Bioinformatics analysis was performed to identify central genes in immune infiltration. Protein-protein interaction (PPI) network was used to identify the hub genes. We then constructed subtypes of endometriosis samples and calculated their correlation with hub genes. qRTPCR and Western blotting were used to verify our findings. Results: We identified 10 candidate hub genes (GZMB, PRF1, KIR2DL1, KIR2DL3, KIR3DL1, KIR2DL4, FGB, IGFBP1, RBP4, and PROK1) that were significantly correlated with immune infiltration. Our study established a detailed immune network and systematically elucidated the molecular mechanism underlying endometriosis from the aspect of immune infiltration. Discussion: Our study provides comprehensive insights into the immunology involved in endometriosis and might contribute to the development of immunotherapy for endometriosis. Furthermore, our study sheds light on the underlying molecular mechanism of endometriosis and might help improve the diagnosis and treatment of this condition.

Identification and validation of core genes for type 2 diabetes mellitus by integrated analysis of single-cell and bulk RNA-sequencing.

BACKGROUND: The exact mechanisms of type 2 diabetes mellitus (T2DM) remain largely unknown. We intended to authenticate critical genes linked to T2DM progression by tandem single-cell sequencing and general transcriptome sequencing data. METHODS: T2DM single-cell RNA-sequencing data were submitted by the Gene Expression Omnibus (GEO) database and ArrayExpress (EBI), from which gene expression matrices were retrieved. The common cell clusters and representative marker genes were ascertained by principal component analysis (PCA), t-distributed stochastic neighbor embedding (t-SNE), CellMarker, and FindMarkers in two datasets (GSE86469 and GSE81608). T2DM-related differentially expressed marker genes were defined by intersection analysis of marker genes and GSE86468-differentially expressed genes. Receiver operating characteristic (ROC) curves were utilized to assign representative marker genes with diagnostic values by GSE86468, GSE29226 and external validation GSE29221, and their prospective target compounds were forecasted by PubChem. Besides, the R package clusterProfiler-based functional annotation was designed to unveil the intrinsic mechanisms of the target genes. At last, western blot was used to validate the alternation of CDKN1C and DLK1 expression in primary pancreatic islet cells cultured with or without 30mM glucose. RESULTS: Three common cell clusters were authenticated in two independent T2DM single-cell sequencing data, covering neurons, epithelial cells, and smooth muscle cells. Functional ensemble analysis disclosed an intimate association of these cell clusters with peptide/insulin secretion and pancreatic development. Pseudo-temporal trajectory analysis indicated that almost all epithelial and smooth muscle cells were of neuron origin. We characterized CDKN1C and DLK1, which were notably upregulated in T2DM samples, with satisfactory availability in recognizing three representative marker genes in non-diabetic and T2DM samples, and they were also robustly interlinked with the clinical characteristics of patients. Western blot also demonstrated that, compared with control group, the expression of CDKN1C and DLK1 were increased in primary pancreatic islet cells cultured with 30 mM glucose for 48 h. Additionally, PubChem projected 11 and 21 potential compounds for CDKN1C and DLK1, respectively. CONCLUSION: It is desirable that the emergence of the 2 critical genes indicated (CDKN1C and DLK1) could be catalysts for the investigation of the mechanisms of T2DM progression and the exploitation of innovative therapies.

High glucose-induced imbalance of mitochondria-associated ER membranes function promotes RSC96 cell damage.

To investigate the effect of high glucose on mitochondrial-related ER membranes (MAMs) in rat Schwann cells (SCs) and the mechanism of cell injury. SCs (RSC96) cells were used as the control group, and RSC96 cells cultured in a high glucose environment for 48 h were set as the experimental group. The level of intracellular calcium was observed by flow cytometry, and ROS levels were detected by DCFH-DA fluorescent probe. The subcellular structure was observed by transmission electron microscopy, focusing on the morphology of mitochondria and endoplasmic reticulum as well as the formation of MAMs. The expression levels of MAMs-related proteins Mfn2, PERK, VDAC1, and IP3R were detected by Western blot. Compared with the control group, after high glucose-induced cells, the level of calcium ion was significantly increased (p<0.01), the level of ROS was significantly increased (p<0.01), mitochondria and endoplasmic reticulum were damaged, and the number of MAMs was increased (p<0.05). Western blot analysis showed that the expression level of Mfn2 was significantly decreased (p<0.01), and the expression levels of PERK, VDAC1, and IP3R were significantly increased (p<0.01). By inducing the imbalance of MAMs function in SCs, high glucose promotes intracellular calcium overload and leads to cell damage.

Effect of 4-AP on MPP+/ MPTP-induced Parkinson's disease model.

To study the effect of 4-AP on Parkinson's disease (PD) cells and animal model. PD cells were pretreated with different concentrations of 4-AP for 24 hours, then PD cells were prepared by MPP+, and the cell activity was detected by CCK8 kit. PD mice were prepared by MPTP and then given 4-AP for 10 days. Finally, the behavioral changes of mice were detected by pole climbing test and open field test, and the expression of TH in the midbrain was detected by IHC and WB. 4-AP could increase the activity of PD cells induced by MPP+. In the field experiment, the total spontaneous activity distance of PD mice (1380.01 ± 151.84) cm was not different from that of 4-AP intervention (1228.65 ± 358.25) cm but was reduced than that of normal mice (2121.89 ± 235.95) (P<0.05). In the pole climbing test, the pole climbing time of PD mice was (7.95 ± 1.02) seconds, compared with that of PD mice treated with 4-AP, there was no difference between the two groups, but it was reduced than that of normal mice (P<0.05). IHC and Western blot showed that the mesencephalic TH of PD mice and drug-treated mice were reduced than that of normal mice (P<0.05), however, drug intervention could not reduce the expression of TH in mice with PD (P>0.5). 4-AP pretreatment can reduce the toxic and side effects of MPP+. 4-AP can not improve the motor function impairment of PD mice, nor can it reduce the toxic effect of MPTP on dopaminergic neurons. There are differences between pre-treatment and post-intervention in the treatment of MPP+/MPTP-induced PD. In order to better explore the drug treatment and target of PD, it is hoped that a cure for PD can be found in PD animals. The timing of intervention and cell and animal experiments should complement each other.

Glucose Starvation Stimulates the Promoting Strength of a Novel Evolved Suc2 Promoter.

Promoters are essential for designing Saccharomyces cerevisiae cell factories. Identifying novel promoters tuned to produce specific metabolites under increasingly diverse industrial stresses is required to improve the economic feasibility of whole fermentation processes. In this study, a positively evolved Suc2 promoter (SUC 2p) with promoter activity stronger than that of the wild-type Suc2 promoter (SUC 2wtp) was obtained. Quantitative real-time PCR, fluorescence analysis, Western blotting, and a ß-galactosidase activity assay revealed that SUC 2p is a medium-strength promoter compared with eight reported promoters at a medium glucose concentration (2% (w/v)). Different glucose concentrations modulated the strength of SUC 2p. Low glucose concentrations (0.05 and 0.5% (w/v)) enhanced the promoter strength of SUC 2p dramatically, with promoter activity higher than that of reported strong promoters. Glucose starvation resulted in the formation of a new Msn2/4 binding site on SUC 2p. Our work should facilitate the development of promoters with novel fine-tuning properties and the construction of S. cerevisiae cell factories suitable for the industrial production of essential chemicals under glucose-deprived conditions.

Silencing lncRNA EZR­AS1 induces apoptosis and attenuates the malignant properties of lung adenocarcinoma cells.

Adenocarcinoma is one of the major subtypes of lung cancer. This study aimed to investigate the effect of silencing long non-coding RNA (lncRNA) EZR­AS1 on the biological behaviors of lung adenocarcinoma (ADC) cells. EZR­AS1 expression levels in lung ADC tissues and cells, as well as in adjacent non-cancerous tissues, were determined using quantitative reverse transcription polymerase chain reaction (qRT-PCR). EZR­AS1 was knocked down in two lung ADC cell lines using small interfering RNA specific for EZR­AS1 (siEZR­AS1). Proliferation, migration, and apoptosis of EZR­AS1-knockdown cells were assessed using the CCK-8 viability assay, flow cytometry, or wound healing experiments. The levels of proteins related to migration pathways were evaluated using western blotting analysis. EZR­AS1 contents were significantly higher in lung ADC tissues and cells than in the levels in the non-cancerous tissues and cells (p<0.01). Transfection of ADC cell lines H1437 and H1975 significantly downregulated EZR­AS1 levels in both cell lines. Cytotoxicity assays revealed that the viability of EZR­AS1-knockdown cells significantly decreased over culture time, and a significant level of apoptosis was induced (p<0.01). Wounding healing experiments revealed that EZR­AS1-knockdown significantly reduced the migration rate of both cell lines (p<0.01). Furthermore, proteins related to migration pathways such as vimentin, MMP2, and MMP9 were significantly downregulated, whereas the E-cadherin level was significantly increased after EZR­AS1 knockdown. Our work demonstrated that EZR-AS1 is associated with ADC progression, and silencing this gene inhibits proliferation and reduces migration of ADC cells in vitro. The altered expression of metastasis-related genes was likely responsible for the reduced migration ability after EZR-AS1 knockdown.

Placental DNA methylation analysis of selective fetal growth restriction in monochorionic twins reveals aberrant methylated CYP11A1 gene for fetal growth restriction.

Fetal growth restriction (FGR) is associated with increased susceptibility to perinatal morbidity and mortality. Evidence suggests that epigenetic changes play critical roles in the regulation of fetal growth. We sought to present a comprehensive analysis of the associations between placental DNA methylation and selective fetal growth restriction (sFGR), which is a severe complication of monochorionic twin pregnancies, characterized by one fetus experiencing restricted growth. Genome-wide methylation analysis was performed on 24 placental samples obtained from 12 monochorionic twins with sFGR (Cohort 1) using Illumina Infinium MethylationEPIC BeadChip. Integrative analysis of our EPIC data and two previous placental methylation studies of sFGR (a total of 30 placental samples from 15 sFGR twins) was used to identify convincing differential promoter methylation. Validation analysis was performed on the placentas from 15 sFGR twins (30 placental samples), 15 FGR singletons, and 14 control singletons (Cohort 2) using pyrosequencing, quantitative real-time polymerase chain reaction, western blot, and immunohistochemistry (IHC). A globe shift toward hypomethylation was identified in the placentas of growth-restricted fetuses compared with the placentas of normal fetuses in monochorionic twins, including 5625 hypomethylated CpGs and 452 hypermethylated CpGs, especially in the regions of CpG islands, gene-body and promoters. The analysis of pathways revealed dysregulation primarily in steroid hormone biosynthesis, metabolism, cell adhesion, signaling transduction, and immune response. Integrative analysis revealed a differentially methylated promoter region in the CYP11A1 gene, encoding a rate-limiting enzyme of steroidogenesis converting cholesterol to pregnenolone. The CYP11A1 gene was validated to have hypomethylation and higher mRNA expression in sFGR twins and FGR singletons. In conclusion, our findings suggested that the changes in placental DNA methylation pattern in sFGR may have functional implications for differentially methylated genes and regulatory regions. The study provides reliable evidence for identifying abnormally methylated CYP11A1 gene in the placenta of sFGR.

Circular RNA METTL15/miR-374a-5p/ESCO2 axis induces colorectal cancer development.

This study investigated the biological role and mechanism of circMETTL15 in colorectal cancer (CRC). Cancer tissues and matched adjacent normal tissues were collected. CircMETTL15, miR-374a-5p, and ESCO2 levels were detected by RT-qPCR and Western Blot. LoVo cells were selected for loss- and gain-of-function assays and rescue assays. Cell proliferation was detected by CCK-8 and colony formation tests, cell apoptosis and cell cycle were detected by flow cytometry, cell migration and invasion were detected by Transwell assay, and protein expression of ki-67, E-cadherin, N-cadherin, and cleaved caspase-3 was detected by Western blot. Through bioinformatics analysis and verification assays, the targeting relationship between circMETTL15, miR-374a-5p, and ESCO2 was studied. The results suggest that circMETTL15 was a stable circRNA that was highly expressed in CRC tissues and cells and was associated with tumor size, higher TNM staging, and lymph node metastasis in CRC patients. Functionally, knocking down circMETTL15 inhibited the proliferation, migration, invasion, and EMT of LoVo cells, and induced apoptosis. Overexpression of circMETTL15 showed the opposite effect. The effects of knockdown or overexpression of circMETTL15 on the biological behavior of LoVo cells were reversed by knockdown of miR-374a-5p or knockdown of ESCO2, respectively. Mechanistically, circMETTL15 acts as a ceRNA for miR-374a-5p to regulate ESCO2 expression, thereby promoting the biological behavior of LoVo cells. In conclusion, the results of this study reveal the role of circMETTL15 in CRC and the underlying molecular mechanism, which provides potential data support for the development of future CRC drugs.

circROCK1 Promotes septic myocardial injury through regulating miR-96-5p/OXSR1 axis.

OBJECTIVE: A recent high-throughput sequencing showed that circular RNA Rho-associated kinase 1 (circROCK1) is abnormally highly expressed in sepsis, but whether it is involved in sepsis development remains unclear. The objective of this study was to investigate the biological function of circROCK1 in sepsis-induced myocardial injury and reveal its potential downstream molecular mechanism. METHODS: Real-time reverse transcriptase-polymerase chain reaction was applied to detect circROCK1 and miR-96-5p expressions in the serum of septic patients. Spearman correlation analysis examined the correlation between circROCK1 and the clinicopathological characteristics of septic patients. The Cecal puncture and ligation (CLP) method was used to establish an in vivo sepsis model. circROCK1 and miR-96-5p expressions in mice were modified by injection of lentivirus or oligonucleotide. The left ventricular systolic pressure, left ventricular end-diastolic pressure, and the maximum increase/decrease rate of left ventricular pressure were checked. ELISA was applied to detect inflammatory factors levels as well as myocardial injury markers levels. Hematoxylin and eosin staining was performed to observe pathological changes in myocardial tissues, and Western blot examined phosphorylated nuclear factor (NF)-κB and oxidative stress-responsive 1 (OXSR1) expression. Dual luciferase reporter experiment was conducted to confirm the targeting relationship between circROCK1, OXSR1, and miR-96-5p. RESULTS: circROCK1 and OXSR1 were highly expressed in sepsis and miR-96-5p was under-expressed. circROCK1 was positively correlated with serum creatinine, C-reactive protein, procalcitonin, and sequential organ failure assessment scores in septic patients. Silencing circROCK1 could improve the diastolic and systolic function of CLP mice, as well as myocardial damage, reduce myocardial tissue edema and necrosis, and inhibit inflammatory factor level and phosphorylated NF-κB expression. Down-regulating miR-96-5p promoted myocardial injury in CLP mice. Silencing circROCK1 and miR-96-5p inhibited and promoted OXSR1 expression, respectively. Both circROCK1 and OXSR1 had a targeting relationship with miR-96-5p. CONCLUSION: CircROCK1 promotes myocardial injury in septic mice by regulating the miR-96-5p/OXSR1 axis, and it can be used as a potential target for treating septic myocardial dysfunction.

Expression signature and prognostic value of CREC gene family in human colorectal cancer.

Colorectal cancer (CRC) is one of the malignant tumors with the highest morbidity and mortality and poor prognosis. The mammalian gene family of Cab45/reticulocalbin/ERC-45/calumenin (CREC) consists of RCN1, RCN2, RCN3, SDF4 and CALU. Although CREC family members have been associated with CRC, the expression pattern, prognostic value, and the role of CREC family in CRC remain unclear. In this study, the expression, survival and biological functions of CREC family in CRC were determined via bioinformatic datasets analysis and experimental verification on clinical CRC specimen. Bioinformatic analysis showed that the expression levels of most CREC family genes were higher in CRC tissues than in normal colorectal tissues. The qPCR and western blot results also revealed that the transcriptional and protein levels of CREC family were elevated in CRC tissues compared with adjacent tissues. Besides, CREC family was significantly correlated with advanced tumor stage and poor prognosis of CRC patients. The expression levels of CREC family had correlations with genomic mutation and methylation, and with the infiltration levels of CD4 + T cells, macrophages, neutrophils, and dendritic cells in the microenvironment of CRC. Functional networks enrichment analysis indicated that the genes of CREC family were essential factors for CRC metastasis. Collectively, these findings suggest that CREC family might be potential targets for the treatment of CRC and candidate prognostic markers for CRC patients.

Revert total protein normalization method offers a reliable loading control for mitochondrial samples following TBI.

Owing to evidence that mitochondrial dysfunction plays a dominant role in the traumatic brain injury (TBI) pathophysiology, the Western blot (WB) based immunoblotting method is widely employed to identify changes in the mitochondrial protein expressions after neurotrauma. In WB method, the housekeeping proteins (HKPs) expression is routinely used as an internal control for sample normalization. However, the traditionally employed HKPs can be susceptible to complex cascades of TBI pathogenesis, leading to their inconsistent expression. Remarkably, our data illustrated here that mitochondrial HKPs, including Voltage-dependent anion channels (VDAC), Complex-IV, Cytochrome C and Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) yielded altered expressions following penetrating TBI (PTBI) as compared to Sham. Therefore, our goal was to identify more precise normalization procedure in WB. Adult male Sprague Dawley rats (N = 6 rats/group) were used to perform PTBI, and the novel REVERT Total Protein (RTP) method was used to quantify mitochondrial protein load consistency between samples at 6 h and 24 h post-injury. Notably, the RTP method displayed superior protein normalization compared to HKPs method with higher sensitivity at both time-points between experimental groups. Our data favors application of RTP based normalization to accurately quantify protein expression where inconsistent HKPs may be evident in neuroscience research.

Activation of autophagy after blast-induced traumatic brain injury in mice.

Injury mechanism and treatment of blast-induced traumatic brain injury (bTBI) has not made a breakthrough so far. Previous reports demonstrate autophagy is involved in regulating the pathophysiological process after TBI. Therefore, this study explored whether autophagy was activated after bTBI. A total of 108 mice were divided randomly into six groups: 6 h, 1 d, 3 d, 7 d, 14 d after bTBI groups and sham group. The protein levels of anti-microtubule associated protein 1 light chain 3B (LC3B, hereafter referred to as LC3), beclin1 and p62 were detected using western blot. Moreover, HO-1 and Nrf2 were localized using histologic staining. Immunofluorescence of LC3 and immunohistochemistry of beclin1 were performed. The autophagy-related ultrastructure was observed by TEM. LC3-II and beclin1 reached their peak on day 3 after bTBI, while p62 showed a continuous downward trend. Immunofluorescence and immunohistochemistry also confirmed that the expression levels of LC3 and beclin1 were the highest at 3 days after bTBI. Autophagic vesicles containing lysosomes or digestive residual structures were observed then. Autophagy was induced in the frontal lobe tissues of bTBI mice induced by moderate-intensity explosion, with a peak at 3d and a gradual decline thereafter.

The amino acid metabolomics signature of differentiating myocardial infarction from strangulation death in mice models.

This study differentiates myocardial infarction (MI) and strangulation death (STR) from the perspective of amino acid metabolism. In this study, MI mice model via subcutaneous injection of isoproterenol and STR mice model by neck strangulation were constructed, and were randomly divided into control (CON), STR, mild MI (MMI), and severe MI (SMI) groups. The metabolomics profiles were obtained by liquid chromatography-mass spectrometry (LC-MS)-based untargeted metabolomics. Principal component analysis, partial least squares-discriminant analysis, volcano plots, and heatmap were used for discrepancy metabolomics analysis. Pathway enrichment analysis was performed and the expression of proteins related to metabolomics was detected using immunohistochemical and western blot methods. Differential metabolites and metabolite pathways were screened. In addition, we found the expression of PPM1K was significantly reduced in the MI group, but the expression of p-mTOR and p-S6K1 were significantly increased (all P < 0.05), especially in the SMI group (P < 0.01). The expression of Cyt-C was significantly increased in each group compared with the CON group, especially in the STR group (all P < 0.01), and the expression of AMPKα1 was significantly increased in the STR group (all P < 0.01). Our study for the first time revealed significant differences in amino acid metabolism between STR and MI.

FGF2 Alleviates Microvascular Ischemia-Reperfusion Injury by KLF2-mediated Ferroptosis Inhibition and Antioxidant Responses.

An essential pathogenic element of acute limb ischemia/reperfusion (I/R) injury is microvascular dysfunction. The majority of studies indicates that fibroblast growth factor 2 (FGF2) exhibits protective properties in cases of acute I/R injury. Albeit its specific role in the context of acute limb I/R injury is yet unknown. An impressive post-reperfusion increase in FGF2 expression was seen in a mouse model of hind limb I/R, followed by a decline to baseline levels, suggesting a key role for FGF2 in limb survivability. FGF2 appeared to reduce I/R-induced hypoperfusion, tissue edema, skeletal muscle fiber injury, as well as microvascular endothelial cells (ECs) damage within the limb, according to assessments of limb vitality, Western blotting, and immunofluorescence results. The bioinformatics analysis of RNA-sequencing revealed that ferroptosis played a key role in FGF2-facilitated limb preservation. Pharmacological inhibition of NFE2L2 prevented ECs from being affected by FGF2's anti-oxidative and anti-ferroptosis activities. Additionally, silencing of kruppel-like factor 2 (KLF2) by interfering RNA eliminated the antioxidant and anti-ferroptosis effects of FGF2 on ECs. Further research revealed that the AMPK-HDAC5 signal pathway is the mechanism via which FGF2 regulates KLF2 activity. Data from luciferase assays demonstrated that overexpression of HDAC5 prevented KLF2 from becoming activated by FGF2. Collectively, FGF2 protects microvascular ECs from I/R injury by KLF2-mediated ferroptosis inhibition and antioxidant responses.

Tibial cortex transverse transport potentiates diabetic wound healing via activation of SDF-1/CXCR4 signaling.

Background: The current treatments for diabetic foot ulcers have disadvantages of slow action and numerous complications. Tibial cortex transverse transport (TTT) surgery is an extension of the Ilizarov technique used to treat diabetic foot ulcers, and can shorten the repair time of diabetic foot ulcers. This study assessed the TTT technique for its effectiveness in healing diabetic foot ulcer skin lesions and its related molecular mechanisms. Methods: Diabetic rat models were established by injecting healthy Sprague-Dawley rats with streptozotocin (STZ). The effects of TTT surgery on the model rats were assessed by recording changes in body weight, analyzing skin wound pictures, and performing H&E staining to assess the recovery of wounded skin. The numbers of endothelial progenitor cells (EPCs) in peripheral blood were analyzed by flow cytometry, and levels of CXCR4 and SDF-1 expression were qualitatively analyzed by immunofluorescence, immunohistochemistry, qRT-PCR, and western blotting. Results: Both the histological results and foot wound pictures indicated that TTT promoted diabetic wound healing. Flow cytometry results showed that TTT increased the numbers of EPCs in peripheral blood as determined by CD34 and CD133 expression. In addition, activation of the SDF-1/CXCR4 signaling pathway and an accumulation of EPCs were observed in skin ulcers sites after TTT surgery. Finally, the levels of SDF-1 and CXCR4 mRNA and protein expression in the TTT group were higher than those in a blank or fixator group. Conclusion: TTT promoted skin wound healing in diabetic foot ulcers possibly by activating the SDF-1/CXCR4 signaling pathway.