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Neutrophils, an important component of the innate immune system, release extracellular traps (NETs) to eliminate invading pathogens by trapping and killing microbes. Recent studies have shown that NETs play a multitude of additional roles in immunity and inflammatory diseases. Therefore, NETs may be involved in persistent hepatitis B virus (HBV) infection, and the objectives of the current study were to determine whether HBV influences NET release and to identify the underlying mechanisms. HBV-infected mice (C57BL/6) were used to detect the efficiency of bacterial eradication by neutrophils in vivo. Primary neutrophils and circulating blood samples were collected from 40 patients with chronic hepatitis B infection, as well as 40 healthy controls, to detect NET release using a Quant-iT Pico Green dsDNA assay, Western blotting, and live-cell imaging and to determine the levels of HBV-DNA and HBV markers. NET release was decreased in patients with chronic hepatitis B infection, and hepatitis B surface Ag, hepatitis B E Ag, and hepatitis B core Ab levels negatively correlated with NET release. We also examined the effect of HBV proteins (HBV X protein, HBV C protein, HBV E protein, and HBV S protein) on NET release in vitro. Based on flow cytometry, cytochrome c reduction assay, and Western blotting, HBV C protein and HBV E protein inhibited NET release by decreasing reactive oxygen species production and autophagy. Overall, HBV may inhibit NET release by modulating reactive oxygen species production and autophagy to escape the immune system and promote the establishment of chronic infection.

BACKGROUND Ischemia-reperfusion injury is associated with vascular dysfunction. The aim of this study was to investigate the role of emodin, a Chinese herbal medicine, in hypoxia-reoxygenation injury in cultured human aortic endothelial cells (HAECs) and its effects on the expression of the peroxisome proliferator-activated receptor-γ (PPAR-γ) and endothelial nitric oxide synthase (eNOS) signaling pathway. MATERIAL AND METHODS An in vitro hypoxia-reoxygenation model used cultured human aortic endothelial cells (HAECs). A colorimetric method evaluated the activity of peroxisome proliferator-activated receptor-γ (PPAR-γ). Phosphorylation of PPAR-γ and endothelial nitric oxide synthase (eNOS) were measured by Western blotting. Expression of inflammatory cytokines, tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-8 were evaluated by enzyme-linked immunosorbent assay (ELISA) and Western blotting. Nitric oxide (NO) production was detected by diaminofluorescein-FM diacetate (DAF-FM DA) fluorescence. Immunoprecipitation was used to evaluate the molecular coupling of heat shock protein (HSP)90 and eNOS. RESULTS Hypoxia-reoxygenation injury of HAECs reduced the activity and phosphorylation of PPAR-γ, and eNOS, NO production, and HSP90/eNOS molecular coupling in a time-dependent manner. Hypoxia-reoxygenation increased the levels of inflammatory cytokines TNF-α, IL-6, and IL-8 in a time-dependent manner. Emodin treatment recovered PPAR-γ activity and phosphorylation, eNOS phosphorylation, and HSP90/eNOS coupling in HAECS in a concentration-dependent manner, which was reversed by the PPAR-γ inhibitor GW9662, and the eNOS inhibitor, L-NAME. The recovery of HSP90/eNOS coupling by emodin was impaired by GW9662 treatment. CONCLUSIONS An in vitro hypoxia-reoxygenation (ischemia-reperfusion injury) model of induction of endothelial cell inflammatory mediators showed that emodin recovered the PPAR-γ and eNOS pathway activity.

BACKGROUND This study was aimed to investigate the protective role of baicalin on vascular endothelium exposed to ischemia reperfusion injury and the involved molecular mechanisms. MATERIAL AND METHODS Cultured human arterial endothelial cells (HAECs) were exposed to hypoxia/deoxygenation (H/R). Cells were also treated with baicalin at serially diluted concentrations. Cells were also treated with PKC activator PEP005 or specific siRNA against protein kinase Cδ (PKCδ). MTT assay was used to evaluate the cell viabilities. Flow cytometry was used to detect cell apoptosis. The protein phosphorylation and expression levels were determined by Western blotting. RESULTS PKCδ-siRNA transfection increased cell viabilities and reduced cell apoptosis in HAECs exposed to H/R. Baicalin treatment preserved cell viabilities and reduced apoptosis of H/R-exposed HAECs in a concentration- dependent manner. Baicalin treatment reduced phosphorylation levels of PKCδ and p53, as well as the expression levels of active caspase3 and bax in HAECs exposed to H/R. The treatment of PKC activator PEP005 impaired the protective effects of baicalin in increasing cell viabilities and reducing apoptosis in HAECs exposed to H/R. CONCLUSIONS Baicalin exerts vascular a protective effect on HAECs exposed to H/R by reducing cell apoptosis. The PKCδ/p53 apoptotic signaling pathway was the pharmacological target of baicalin.

Background Exercise training is beneficial for cardiac rehabilitation. Nevertheless, few study focused on the role of high-intensity interval training (HIIT) in cardiac repair. The current study aimed to elucidate the effect of HIIT on cardiac rehabilitation and the involved mechanisms after acute myocardial infarction (MI). Methods A total of 65 male rats underwent coronary ligation or sham operation and were randomly assigned to 4 groups: sham (n = 10), sedentary (MI-Sed, n = 12), moderate-intensity continuous training (MI-MCT, n = 12) and HIIT (MI-HIIT, n = 12). One week after MI induction, adaptive training starts follow by formal training. After the experiment, cardiac functions were determined by echocardiography and hemodynamic measurements. Changes in infarct size, collagen accumulation, myofibroblasts, angiogenesis, inflammation level, endothelin-1 (ET-1), and renin-angiotensin-aldosterone system (RAAS) activities were measured. Data were analyzed by one-way ANOVA. Results After MI, cardiac structure and function were significantly deteriorated. However, post-MI HIIT for 8 weeks had significantly ameliorated left ventricular end-diastolic pressure (LVEDP), LV systolic pressure (LVSP), and maximum peak velocities of relaxation (–dP/dtmax). Moreover, it preserved cardiac functions, reduced infarct size, protected the myocardium structure, increased angiogenesis and decreased the myofibroblasts and collagen accumulation. HIIT for 4 weeks had no effect on LVEDP, –dP/dtmax, infarct size and angiogenesis. Additionally, it induced inflammation response and repressed ET-1 and RAAS activities were found in myocardium and peripheral circulation after HIIT. Conclusion Our results suggested that post-MI HIIT had a positive role in cardiac repair, which might be linked with the induction of inflammation and inhibition of ET-1 and RAAS activities.

Endometrioid endometrial carcinoma (EEC) is the most common gynaecologic malignancy worldwide. Long non‐coding RNAs have previously been demonstrated to play important roles in regulating human diseases, particularly cancer. However, the biological functions and molecular mechanisms of long non‐coding RNAs in EEC have not been extensively studied. Here, we describe the discovery of Lnc‐NA from the promoter of the transcription factor nuclear receptor subfamily 4 group A member 1 (NR4A1) gene. The role and function of Lnc‐NA in EEC remain unknown. In this study, we used quantitative real‐time polymerase chain reactions to confirm that Lnc‐NA expression was down‐regulated in 30 EEC cases (90%) and in EEC cell lines compared with that in the paired adjacent tissues and normal endometrial cells. In vitro experiments further demonstrated that overexpressing Lnc‐NA decreased EEC cell proliferation, migration and invasion and promoted apoptosis via inactivation of the apoptosis signalling pathway. Moreover, the results show that Lnc‐NA expression was positively correlated with NR4A1. Furthermore, Lnc‐NA regulated NR4A1 expression and activated the apoptosis signalling pathway to inhibit tumour progression. In summary, our results demonstrate that the Lnc‐NA‐NR4A1 axis could be a useful tumour suppressor and a promising therapeutic target for EEC.

FK506-binding protein 51 (FKBP51) is a member of the immunophilin family, with relevant roles in multiple signaling pathways, tumorigenesis and chemoresistance. However, the function of FKBP51 in papillary thyroid carcinoma (PTC) remains largely unknown. In the present study, increased FKBP51 expression was detected in PTC tissues as compared with adjacent normal tissues, and the expression level was associated with clinical tumor, node and metastasis stage. Using FKBP51-overexpressing K1 cells and FKBP51-knockdown TPC-1 cells, both human PTC cell lines, it was identified that FKBP51 promoted the migration and invasion of PTC, without affecting cell proliferation. Further investigation revealed that FKBP51 activated the NF-κB pathway and epithelial-to-mesenchymal transition (EMT) genes, and EMT was suppressed when NF-κB was inhibited. It was also assessed whether FKBP51 promoted the formation of cytoskeleton to promote migration and invasion of PTC using a tubulin tracker; however, no evidence of such an effect was observed. These results suggested that FKBP51 promotes migration and invasion through NF-κB-dependent EMT.

Iron toxicity is a major nutrient disorder that severely affects crop development and yield. Vacuolar detoxification of metal stress is an important strategy for plants to survive and adapt to this adverse environment. Vacuolar iron transporter (VIT) members are involved in this process and play essential roles in iron storage and transport. In this study, a rapeseed VIT gene BnMEB2 (BnaC07g30170D) was identified. BnMEB2 is a homolog to Arabidopsis MEB2 (At5g24290) and acts as a detoxifier in vacuolar sequestration of divalent metal. Transient expression analysis revealed that BnMEB2 was localized to the vacuolar membrane. Q-PCR detection showed a high expression of BnMEB2 in mature (60-day-old) leaves and could be obviously induced by exogenous iron stress in both roots and leaves. Over-expressed BnMEB2 in both Arabidopsis wild type and meb2 mutant seedlings resulted in greatly improved iron tolerability with no significant changes in the expression level of other vacuolar iron transporter genes. The mutant meb2 grew slowly and its root hair elongation was inhibited under high iron concentration condition while BnMEB2 over-expressed transgenic plants of the mutant restored the phenotypes with apparently higher iron storage in roots and dramatically increased iron content in the whole plant. Taken together, these results suggested that BnMEB2 was a VIT gene in rapeseed which was necessary for safe storage and vacuole detoxification function of excess iron to enhance the tolerance of iron toxicity. This research sheds light on a potentially new strategy for attenuating hazardous metal stress from environment and improving iron biofortification in Brassicaceae crops.