Mammalian Target of Rapamycin (mTOR) Inhibitor Improves Local Immune Microenvironment and Reduces Seizures via Increasing miR-211 Level in Rat Brain

This study aims to analyze the role of mTOR inhibitor on the expression of miR-211 in rat brain tissue and the biological effect of miR-211 in attenuating seizure. Rats were randomly divided into four groups, and the number of seizures and the duration of single seizure were observed within 24 hours after intervention. The level of miR-211 in brain tissue was detected by RT qPCR, the apoptosis of nerve cells was assessed by TUNEL staining, the level of immune cells was detected by flow cytometry, and the level of serum inflammatory factors was determined by ELISA. The number of seizures and the duration of single seizure in the three groups treated by rapamycin within 24 hours were lower than those in the control group, and the symptom relief in group C was the best. After treatment, the expression level of miR-211 in the brain tissue of epileptic rats increased. TUNEL staining showed that neuronal apoptosis was obvious in epileptic rats. The anti apoptotic ability of group C was the most significant, followed by group D and group B. Compared with group A, the levels of CD3+ cells, CD8+ cells and CD4+/CD25+ cells in brain tissue of group C were decreased, while the levels of IL-2 and IFN-γ were lower in group C than those in control. In group C (n = 5), the levels of CD3+ cells, CD8+ cells and CD4+/CD25+ cells were elevated, and the levels of immune related cytokines IL-2 and IFN-γ were higher than those of rats without miR-211 inhibition. mTOR inhibitors can improve the local immune microenvironment, reduce the release of inflammatory factors, and finally decrease the frequency and duration of seizures by up regulating the level of miR-211 in rat brain tissue.

Autologous Oxygen-Releasing Nano-Biomimetic Scaffold with Chondrocytes Promotes Joint Repair After Trauma

Our study assesses the role of a scaffold constructed by co-culture of autologous oxygen-releasing biomimetic scaffold (AONS) and chondrocytes in joint repair after trauma. A composite scaffold structure was used and a scaffold constructed of AONS and chondrocytes was transplanted into SD rats to create models of patellar cartilage fracture and hip osteochondral fracture, respectively followed by analysis of cell proliferation by immunofluorescence method, osteogenesis-related gene expression by RT-PCR, chondrocytes apoptosis by TUNEL staining. The blank control group and AONS composite chondrocytes have significant differences in apoptosis and cell proliferation of two fracture types (P <0.05). The autologous oxygen-releasing nanometers at 4 and 8 weeks showed a significant difference in the number of PCNA and TUNEL cells between biomimetic scaffold and chondrocytes in two groups (P < 0.05). The AONS and chondrocytes were effective for two types of fractures at 1, 4 and 8 weeks. The expression of various markers of intrachondral osteogenesis was decreased and the markers of hip osteochondral fracture were increased significantly (P < 0.05). Joint recovery was better than patellar cartilage fractures. The AONS composite chondrocyte scaffold promotes repair of patellar cartilage fractures and hip osteochondral fractures with a better effect on hip osteochondral fractures.

Exosomal MicroRNA-325 Enhances Trophoblast Migration and Invasion Through Downregulation of Lethal-7b and Upregulation of Forkhead Box Protein O1 Expression in Preeclampsia

We aimed to explore the mechanism by how microRNA (miRNA)-325 derived from marrow mesenchymal stem cell exosomes (MSC-exos) affects the trophoblast progression in preeclampsia (PE). RT-qPCR detected the level of miRNA let-7b and FOXO1 in the placenta tissue of PE patients. Functional experiment was performed to analyze the effect of FOXO1 inhibitor and let-7b mimics on cell migration, invasion and apoptosis through Transwell assay and TUNEL staining. The trophoblast cell was co-cultured with overexpressed-miR-325 MSC-exos to measure gene expression and cell progression. let-7b was highly and FOXO1 was lowly expressed in PE placenta tissue. let-7b directly targeted and inhibited FOXO1 expression. Importantly, as miR-325 was internalized by trophoblast cells through MSC-exos, MSC-exos overexpressing miR-325 inhibited let-7b expression in trophoblasts, up-regulated FOXO1 and activated AKT signaling pathway. Further, MSC-exos treatment promoted invasion and migration of trophoblast cell and inhibited apoptosis. In conclusion, miR-325 derived from MSC-exos promotes the invasion and migration of trophoblast cells in PE through inhibition of let7b and upregulation of FOXO1.

Intestinal Epithelial Cell Exosome Launches IL-1β-Mediated Neuron Injury in Sepsis-Associated Encephalopathy

BackgroundGut–microbiota–brain axis links the relationship between intestinal microbiota and sepsis-associated encephalopathy (SAE). However, the key mediators between them remain unclear.MethodsMemory test was determined by Water maze. Intestinal flora was measured by 16S RNA sequencing. Neurotransmitter was detected by high-performance liquid chromatography (HPLC). Histopathology was determined by H&amp;E, immunofluorescence (IF), and terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) staining. Flow cytometry was employed to determine the proportion of macrophages.ResultsFecal microbiota transplantation (FMT) relieved hippocampus impairment of SAE rats by inhibiting inflammation cytokine secretion, the expression of IBA-1 and neurotransmitter disturbance, and cell apoptosis and autophagy, accompanied by the reduced M1 polarization and M1 pro-inflammation factors produced by macrophages in mesenteric lymph nodes (MLNs). Actually, M1 polarization in SAE rats depended on intestinal epithelial cell (IEC)-derived exosome. GW4869-initiated inhibition of exosome secretion notably abolished M1 polarization and the secretion of IL-1β. However, GW4869-mediated improvement of hippocampus impairment was counteracted by the delivery of recombinant interleukin (IL)-1β to hippocampus. Mechanistically, IEC-derived exosome induced the excessive circulating IL-1β produced by CP-R048 macrophages, which subsequently induced damage and apoptosis of hippocampal neurons H19-7 in an autophagy-dependent manner. And reactivation of autophagy facilitates intestinal IL-1β-mediated hippocampal neuron injury.ConclusionCollectively, intestinal flora disturbance induced the exosome release of IECs, which subsequently caused M1 polarization in MLNs and the accumulation of circulating IL-1β. Circulating IL-1β promoted the damage and apoptosis of neurons in an autophagy-dependent manner. Possibly, targeting intestinal flora or IEC-derived exosome contributes to the treatment of SAE.

A20 (TNFAIP3) alleviates viral myocarditis through ADAR1/miR-1a-3p-dependent regulation

Objective To investigate the effect of A20 and how A20 is regulated in viral myocarditis (VMC). Methods BABL/C mice, primary neonatal rat cardiomyocytes and H9c2 cells were infected with Coxsackie virus B3 (CVB3) to establish animal and cellular models of VMC. H&E staining revealed the pathologic condition of myocardium. ELISA measured the serum levels of creatine kinase, creatine kinase isoenzyme and cardiac troponin I. The effects of A20, miR-1a-3p and ADAR1 were investigated using gain and loss of function approaches. ELISA measured the levels of IL-6, IL-18 and TNF-α in serum or cell culture supernatant. TUNEL staining and flow cytometry assessed the apoptosis of myocardium and cardiomyocytes, respectively. RNA-binding protein immunoprecipitation and dual-luciferase reporter assays verified the binding between A20 and miR-1a-3p. Co-immunoprecipitation assay verified the binding between ADAR1 and Dicer. Results A20 was underexpressed and miR-1a-3p was overexpressed in the myocardium of VMC mice as well as in CVB3-infected cardiomyocytes. Overexpression of A20 suppressed cardiomyocyte inflammation and apoptosis in vivo and in vitro. miR-1a-3p promoted CVB3-induced inflammation and apoptosis in cardiomyocytes by binding to A20. The expression of miR-1a-3p was regulated by ADAR1. ADAR1 promoted the slicing of miR-1a-3p precursor by binding to Dicer. Conclusion A20, regulated by ADAR1/miR-1a-3p, suppresses inflammation and cardiomyocyte apoptosis in VMC.

Neuroprotective effects of crude extract of Crataegus songarica on a rat model of traumatic brain injury

Purpose: To investigate the protective effect of Crataegus songarica extract (CSCE) against traumatic brain injury (TBI) in rats, and the underlying mechanism of action. Methods: A rat model of TBI was established via tracheal intubation procedure, and the rats were treated with graded doses of CSCE. Neuronal survival was determined by Nissl staining, while neuronal apoptosis was measured using TUNEL-staining. Neurological impairments were determined based on neurological severity score (NSS). Results: Treatment of TBI rats with CSCE enhanced neuronal survival and decreased TUNEL-positive cell fraction in the brain cortex. The treatment prevented elevation of NSS and suppressed mRNA and protein expression levels of IL-6 and TNF-α in brain cortex. Moreover, CSCE treatment prevented TBI-mediated suppression of activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and attenuated hydrogen peroxide (H2O2) levels in TBI rat brain cortex. Treatment of TBI rats with CSCE down-regulated NF-κB expression, increased Nrf2 expression and up-regulated mRNA expressions of heme oxygenase 1 (HO-1) and quinine oxidoreductase 1 (NQO-1). Conclusion: These results suggest that CSCE prevents TBI-mediated reduction in neuronal survival and inhibits brain cortical neuronal death in rats. It improves NSS and inhibits inflammatory response via activation of Nrf2 pathway and targeting of NF-κB expression. Therefore, CSCE is a potential therapeutic agent for TBI.

Ghrelin reduces cerebral ischemic injury in rats by reducing M1 microglia/macrophages

The purpose of this study was to investigate the effect of Ghrelin on the polarization of microglia/ macrophages after cerebral ischemia (CI) in rats. 60 wild-type SD rats were randomly divided into sham group, CI group, CI+Ghrelin group, 20 rats in each group. The modified Longa suture method was used to establish the middle cerebral artery occlusion (MCAO) model in rats. Before surgery, Ghrelin was injected subcutaneously (100μg/kg, twice a day) for 4 consecutive weeks. After modeling, neurological function scores were performed with three behavioral experiments: mNSS score, Corner test, and Rotarod test, to evaluate the recovery of neurological function after Ghrelin treatment. At the same time, the brain tissues were collected and stained with 2,3,5-triphenyltetrazolium chloride (TTC) to detect the cerebral infarct volume. RT-qPCR was used to detect the expression of TNF-α and IL-1β in the ischemic brain tissue, and the TUNEL staining was used to detect the apoptosis of brain tissue. Flow cytometry was used to detect the percentage of M1 type microglia/macrophages which were isolated by trypsin digestion of fresh cerebral cortex. Then, the Western blotting and immunofluorescence method were used to detect the phosphorylation level of AKT (P-AKT) and AKT. Compared with the CI group, the neurological function of the rats in the CI+Ghrelin group was dramatically improved, and the cerebral infarction area was dramatically reduced. At the same time, the expression of TNF-α and IL-1β in the ischemic brain tissue of rats in the CI+Ghrelin group decreased, and the apoptotic cells in the brain tissue also decreased. Compared with the CI treatment group, the activation of M1 microglia/macrophages in the cortex of the ischemic side of the infarct and the peri-infarct area in the CI+Ghrelin group was dramatically inhibited. At the same time, the ratio of P-AKT/AKT of the brain tissue in the CI+Ghrelin group was dramatically higher than that of the CI group. In the rat cerebral ischemia model, Ghrelin can promote the repair of brain damage and the recovery of neurological function after ischemia. Its mechanism may be related to activating AKT to selectively reduce M1 microglia/macrophages, reducing inflammation and cell apoptosis in brain tissue.

Dexrazoxane Alleviated Doxorubicin-Induced Nephropathy in Rats

<b><i>Introduction:</i></b> Doxorubicin (DOX), an anthracycline antitumor agent, has been widely used against various solid tumors and hematological malignancies. However, the clinical application of DOX is restricted by its multiple organ toxicity including nephrotoxicity. This study investigated the protective effects and mechanisms of dexrazoxane (DZR) against DOX-induced nephropathy in rats. <b><i>Methods:</i></b> Male Sprague Dawley rats received 2.5 mg/kg DOX once a week for 5 consecutive weeks. 24-h urinary protein and renal function injury biomarkers were determined to evaluate the renal function. Histopathological changes and glomerulosclerosis were examined by hematoxylin and eosin and periodic acid-Schiff staining. The change of renal ultrastructure in the DOX-induced rats was observed by the electron microscopy. The renal apoptosis was detected by TUNEL staining and measured the protein expression of Caspase-3, Bcl-2, and Bax. Renal interstitial fibrosis was determined by Masson staining and immunohistochemistry examination. The levels of vimentin, alpha-smooth muscle actin (α-SMA), and transforming growth factor β (TGF-β) in kidney tissue were detected by Western blot. <b><i>Results:</i></b> DZR pretreatment markedly raised the survival rate and improved the renal dysfunction in DOX-treated rats. DZR ameliorated DOX-induced histopathological lesion of glomerular and tubular and apoptosis. DZR restored the oxidant/antioxidant balance via regulating the levels of MDA, SOD, and TAC. DZR reduced DOX-induced collagen IV deposition and renal interstitial fibrosis and downregulated the fibrosis-related protein expressions of vimentin, α-SMA, and TGF-β1. <b><i>Conclusion:</i></b> Our results suggest DZR exerted its protective effects against DOX-induced nephropathy through inhibition of lipid peroxidation, apoptosis, and fibrosis.

NEAT1 Enhances MPP+-Induced Pyroptosis In SH-SY5Y Cells Via Targeting Mir-5047/YAF2 Signaling

Parkinson’s disease (PD) is the second most frequent neurodegenerative disease. The aim of our study is to explore the role and regulatory mechanism of long non-coding RNA (lncRNA) NEAT1 in the MPP+-induced neuron pyroptosis. The levels of miR-5047 and YAF2 mRNA were determined through qRT-PCR. TUNEL staining was carried out to analyze neuronal apoptosis. Luciferase activity assay was accomplished to analyze the combination of miR-5047 and NEAT1 and YAF2 3’-UTR. Besides, the concentrations of IL-1β and IL-18 in supernatant were analyzed by ELISA assay. The levels of protein were examined through Western blot. NEAT1 and YAF2 expression were increased, while miR-5047 level was declined in the SH-SY5Y cells treated with MPP+. NEAT1 was a positively regulator for the SH-SY5Y cells pyroptosis induced by MPP+. In addition, YAF2 was a downstream target of miR-5047. NEAT1 promoted YAF2 expression via inhibiting miR-5047. Importantly, the promotion of NEAT1 to SH-SY5Y cells pyroptosis induced by MPP+ was recused by miR-5047 mimic transfection and YAF2 downregulation. In conclusion, NEAT1 was increased in the SH-SY5Y cells treated with MPP+, and it promoted the MPP+-induced pyroptosis through facilitating YAF2 expression by sponging miR-5047.

Endoplasmic reticulum stress and the unfolded protein response in skeletal muscle of subjects suffering from peritoneal sepsis

We provide a descriptive characterization of the unfolded protein response (UPR) in skeletal muscle of human patients with peritoneal sepsis and a sepsis model of C57BL/6J mice. Patients undergoing open surgery were included in a cross-sectional study and blood and skeletal muscle samples were taken. Key markers of the UPR and cluster of differentiation 68 (CD68) as surrogate of inflammatory injury were evaluated by real-time PCR and histochemical staining. CD68 mRNA increased with sepsis in skeletal muscle of patients and animals (p < 0.05). Mainly the inositol-requiring enzyme 1α branch of the UPR was upregulated as shown by elevated X-box binding-protein 1 (XBP1u) and its spliced isoform (XBP1s) mRNA (p < 0.05, respectively). Increased expression of Gadd34 indicated activation of PRKR-Like Endoplasmic Reticulum Kinase (PERK) branch of the UPR, and was only observed in mice (p < 0.001) but not human study subjects. Selected cell death signals were upregulated in human and murine muscle, demonstrated by increased bcl-2 associated X protein mRNA and TUNEL staining (p < 0.05). In conclusion we provide a first characterization of the UPR in skeletal muscle in human sepsis.