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miR-150 was found to target the 3′-untranslated regions of AKT3, and the AKT pathway was affected by SR protein kinase 1 (SRPK1). However, the expression and significance of miR-150, AKT3 and SRPK1 in acute lung injury (ALI) were not clear. Here, we found that the expression of miR-150 was significantly reduced, while the expression of AKT3 and SRPK1 were markedly increased in LPS-treated A549, THP-1 and RAW 264.7 cells. miR-150 significantly decreased levels of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α, reduced the expression of AKT3, but had no impact on SRPK1 expression compared with the control group in LPS-treated A549, THP-1 and RAW 264.7 cells. AKT3 silencing only reduced the production of pro-inflammatory cytokines and showed no effect on miR-150 and SRPK1 expression. Finally, we observed that miR-150 mimics and/or silencing of SRPK1 decreased the expression of AKT3 mRNA. Besides, over-expression of miR-150 or silencing of SRPK1 also reduced the expression of AKT3 protein, which exhibited the lowest level in the miR-150 mimics plus si-SRPK1 group. However, si-SRPK1 had no effect on miR-150 level. In conclusion, miR-150 and SRPK1 separately and cooperatively participate into inflammatory responses in ALI through regulating AKT3 pathway. Increased miR-150 and silenced SRPK1 may be a novel potential factor for preventing and treating more inflammatory lung diseases.

Sixteen dihydroartemisinin-5-methylisatin hybrids 6a–c and 7a–m tethered via different carbon spacers were assessed for their antiproliferative activity against MCF-7, MDA-MB-231, MCF-7/ADR and MDA-MB-231/ADR breast cancer cell lines as well as cytotoxicity towards MCF-10A cells to investigate the influence of the length of carbon spacers on the activity. The preliminary results illustrated that the length of the carbon spacer was the main parameter which affected the activity, and hybrids tethered via the two-carbon linker showed the highest activity. Amongst the synthesized hybrids, the representative hybrid 7a (IC50: 15.3–20.1 µM) not only demonstrated profound activity against both drug-sensitive and drug-resistant breast cancer cell lines, but also possessed excellent safety and selectivity profile. Collectivity, hybrid 7a was a promising candidate for the treatment of both drug-sensitive and drug-resistant breast cancers and worthy of further preclinical evaluations.

MiR-150 is involved into some pathological processes, such as tumorigenesis and autoimmune diseases. However, little is known about the involvement of miR-150 in human sepsis. In this study, plasma miR-150 level had a diagnostic and independent prognostic value in patients with sepsis, and negatively correlated with renal dysfunction and 28-day survival as well as plasma levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). MiR-150 expression was also significantly decreased in human umbilical vein endothelial cells (HUVECs) and C57BL/6 mice with sepsis after lipopolysaccharides (LPS) treatment. In-vitro, miR-150 over-expression protected HUVECs from LPS-induced apoptosis and the expressions of nuclear factor-κB1 (NF-κB1), IL-6, TNF-α, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin. Furthermore, NF-κB1 was identified as a direct target of miR-150. Restored NF-κB1 expression antagonized the protective effects of miR-150, while suppression of NF-κB1 enhanced these protective effects. Our findings indicate miR-150 predicts survival in patients with sepsis and inhibits LPS-induced inflammatory factors and apoptosis by targeting NF-κB1 in human umbilical vein endothelial cells. Thus, miR-150 may be a useful biomarker or target in the diagnosis, prognosis and treatment of patients with sepsis.

In recent years, the insulin-like growth factor (IGF-1) and serine-arginine protein kinase 1 (SRPK1) have been reported to be implicated in the pithelial-mesenchymal transition (EMT) in many kinds of malignancies. However, the potential roles of IGF-1-SRPK1 signaling in the EMT of gastric cancer (GC) have not been investigated. In the present study, the in-vitro assays were used to investigate the molecular role of SRPK1 in cell cycle, motility and invasiveness. We demonstrated that the expressions of SRPK1 or insulin-like growth factor receptor 1 (IGF1R) were significantly increased in GC tissues and cells than those in normal tissues and GES-1 cells, and closely associated with metastasis, stage and prognosis. Western blot analysis showed that IGF-1 treatment can induce the expression of p-AKT and EMT biomarkers (N-cadherin, MMP2 and Slug) in a dose-dependent fashion in MGC803 and BGC823 cells. On the other hand, the knockdown of SRPK1 attenuated IGF-1-induced increase of EMT biomarkers and p-AKT. Besides, in-vitro analysis showed that knockdown of SRPK1 induced cell cycle arrest in G0/G1 phase, and affected cell migration and invasion. In conclusion, IGF-1-IGF1R pathway induced the expression of SRPK1 to control the progression of EMT via AKT pathway in the development of GC. Our findings lay a promising foundation for the IGF-1-IGF1R axis-targeting therapy in GC patients.

In recent decades, microRNAs (miRNAs) have been reported to play an important role in the pathogenesis of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). To explore the underlying mechanisms of miR-297 in ALI/ARDS, we investigated its role in lipopolysaccharide (LPS)-induced A549 cell and mice lung injury model. We found that the expression of miR-297 decreased in LPS-induced A549 cells or serum of ALI/ARDS mice. Moreover, LPS suppressed A549 cell viability, promoted apoptosis and increased the expressions of inflammatory and autophagy-related factors. Conversely, overexpression of miR-297 increased cell proliferation and reduced cell apoptosis, and alleviated inflammatory cytokines secretion and autophagy in the presence of LPS. Importantly, miR-297 directly inhibited transcription of cyclin dependent kinase 8 (CDK8) by binding to the 3'-untranslated region (3'-UTR) of CDK8 mRNA, and the expression of CDK8 was negatively regulated by miR-297. Silencing of CDK8 promoted the anti-inflammatory and anti-apoptotic effects of miR-297 in LPS-mediated A549 cells. The expressions of phosphorylated p65 (p-p65)/p65 and phosphorylated inhibitor kappa B-α (p-IκBα)/IκBα were dramatically decreased by miR-297 mimics and silencing of CDK8. In vivo, miR-297 alleviated LPS-induced inflammatory responses and lung injury in ALI/ARDS mice. In conclusion, our findings suggested that miR-297 affects nuclear factor-kappa B (NF-κB) pathway to alleviate LPS-induced A549 cell and mice lung injury via targeting CDK8 expression.

Protective effect of phosphodiesterase 5 (PDE5) inhibitor sildenafil on hypoxic injury of isolated myocardial cells and its mechanism of action were investigated. Myocardial cells of neonatal mice were isolated, cultured and divided into blank, control, and PDE5 inhibitor group. Cells in the control and the PDE5 inhibitor group were treated with hypoxia and serum deprivation for 6 h to simulate the myocardial ischemia process in vivo, while those in the PDE5 inhibitor group were treated with 1 µmol/l sildenafil. The cell viability was detected via Cell Counting kit-8 (CCK-8), the cytotoxicity was detected via lactate dehydrogenase release assay, and the apoptosis level was detected via flow cytometry, Hoechst staining and caspase-3 activity assay. Moreover, changes in mitochondrial membrane potential of myocardial cells were detected via JC-1 staining and flow cytometry, fluorescein adenosine triphosphate (ATP) assay kit was used to detect the production of ATP in myocardial cells, and reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the level of Sirt3 messenger ribonucleic acid (mRNA) in myocardial cells. Finally, the expression and changes of Sirt3, peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and acetylated PGC-1α were detected via western blot analysis. After hypoxia treatment, the cell viability was decreased, the cytotoxic effect was enhanced, the percentage of apoptosis was increased, the activity of apoptosis-related protein was increased, the mitochondrial membrane potential was decreased, the production of ATP was reduced, the expression of Sirt3 was decreased, and the acetylation level of PGC-1α was increased. However, after pretreatment with sildenafil, the damage to membrane potential of myocardial cells was significantly alleviated, and the production of ATP was increased. At the same time, myocardial cell apoptosis was decreased, Sirt3 expression was increased and PGC-1α acetylation was decreased. PDE5 inhibitor inhibits apoptosis of hypoxic myocardial cells through protecting mitochondrial function.

MicroRNAs (miRNAs) play a vital role in regulating tumor progression. Dysregulated miR-136 expression was linked to the development of various human cancers. In the present study, we investigated the expression and relationship of miR-136 and COX2 in hepatocellular carcinoma (HCC) using relevant experiments, involving CCK-8, Transwell assay, and luciferase reporter assay. We demonstrated that miR-136 expression is obviously decreased in HCC tissues and cells, and negatively correlated with the expression of COX2 mRNA. In vitro assay revealed that overexpression of miR-136 significantly changed the expression of proliferation- and metastasis-related proteins and inhibited the proliferation, migration, and invasion of HepG2 and Hep3B cells. Dual-luciferase reporter assay validated that the 3′-untranslated region (3′-UTR) of COX2 is a direct target of miR-136. Furthermore, COX2 siRNA partially enhanced the miR-136 overexpression-induced inhibitory effects. In conclusion, miR-136 was vital in the regulation of HCC cell proliferation and metastasis by targeting COX2. Thus, our findings provided novel evidence that miR-136 might be recommended as a potential target for the diagnosis and treatment of HCC patients.

Acute lung injury (ALI) and its severe manifestation of acute respiratory distress syndrome (ARDS) in human lung are induced by inflammatory cytokines and endogenous factors such as miRNAs. However, the role of miR-150 in lipopolysaccharide (LPS)-induced ALI is not clear. Here, we found miR-150 expression was significantly reduced in the serum of patients with ARDS, and negatively associated with the disease severity and 28-day survival of ARDS. In vivo, miR-150 decreased total cell and neutrophil counts, and production of inflammatory cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) as well as levels of total protein, albumin and IgM in the bronchoalveolar lavage (BAL) fluid in LPS-induced ALI mice. Meanwhile, miR-150 improved the 72 h survival rate of LPS-induced ALI mice. In-vitro assays demonstrated that miR-150 alleviated LPS-induced A549 cell apoptosis, autophagy, and release of inflammatory cytokines. Further, AKT3 was a direct target of miR-150. Silencing of AKT3 partially reversed LPS-induced A549 cell injury, and enhanced the protective effects of miR-150. In addition, miR-150 or si-AKT3 effectively inhibited the phosphorylation levels of c-Jun N-terminal kinase (JNK) and nuclear factor-κB (NF-κB) (p65 and IκBα). In conclusion, miR-150 alleviated LPS-induced acute lung injury via directly targeting AKT3 expression or regulating JNK and NF-κB pathways, which may be a promising therapeutic strategy to treat ALI/ARDS.