Objective To investigate the effects of exosomes from cultured human retinal pigment epithelium (ARPE-19) cells affected by oxidative stress on the proliferation and expression of vascular endothelial growth factor-A (VEGF-A) and Akt of ARPE-19 cells. Methods Culture ARPE-19 cells. The concentration of 2.5 μmol/L rotenone was selected to simulate oxidative stress and isolated ARPE-19-exosome. Exosomes were isolated by ExoQuick exosome precipitation solution. Transmission electron microscopy was used to identify the morphology of exosomes. Western blot was used to detect exosomes’ surface-specific maker protein CD63. ARPE-19 cells affected by oxidative stress were cultured with exosome as experimental group, normal ARPE-19 cells were cultured with exosome as control group. The cell proliferation was examined by methyl thiazolyl tetrazolium assay. Western blot and immunofluorescence assay were used to detect the expression levels of VEGF-A and Akt protein. Real-time quantitative polymerase chain reaction (RT-PCR) was used to detect the levels of VEGF-A mRNA and Akt mRNA. Results The diameter of normal ARPE-19-exosomes ranged from 50 to 150 nm. The isolated exosomes expressed CD63. AREP-19 cells were cultured with ARPE-19 (affected by rotenone)-exosome, the cell viability in experimental group was significantly reduced than in the control group. Green fluorescence was observed in the cytoplasm under fluorescence microscope. Compared with the control group, VEGF-A was up-regulated expressed and Akt was down-regulated expressed. Western blot results showed that, VEGF-A protein expression in the experimental group were higher than the control group. Akt protein expression in the experimental group were less than the control group. The difference was statically significant (t=3.822, 6.527;P＜0.05). RT-PCR results showed that VEGF-A mRNA expression levels was higher in the experimental group than the control group. Akt mRNA expression levels was lower in the experimental group than the control group. The difference was statically significant (t=8.805, −7.823;P＜0.05). Conclusions Exosomes from ARPE-19 cells affected by oxidative stress inhibit the proliferation of normal ARPE-19 cells, increase the expression of VEGF-A and reduce the expression of Akt.
ObjectiveTo summarize the biological function and molecular regulation mechanism of serine threonine tyrosine kinase 1 (STYK1) in tumor occurrence and development. MethodThe relevant literature about STYK1 and tumor progression in recent years was searched and reviewed. ResultsThe expression of STYK1 was up-regulated in a variety of tumors and was related to the prognosis. STYK1 might regulate the proliferation, apoptosis, migration, metastasis, aerobic glycolysis, drug resistance and other biological functions of tumor cells through MEK/ ERK, PI3K/AKT, JAK/STAT and their targeting proteins, and promote the malignant progress of tumors. Conclusion STYK1is expected to become a new target for the treatment of malignant tumors, but the molecular mechanism of its regulation of tumor progression and its upstream regulators need to be further explored.
Objective To analyze the metabolic characteristics of myocardial infarction (MI) using metabolomics to better understand its pathogenesis and to explore new therapeutic directions for MI. Methods Serum metabolites in ten acute MI mice and five sham-control mice were analyzed by UHPLC-QqQ/MS, and SPSS was used for statistical analysis. MetaboAnalyst 5.0 was used to analyze the metabolic pathways of the differential metabolites and build a metabolic network. Results One hundred and twenty-nine metabolites were detected by UHPLC-QqQ/MS. Significant serum metabolite differences were found between MI mice and normal controls. Fifty out of 129 metabolites in serum were associated with MI. In addition, the most important metabolic pathways were D-glutamate metabolism, alanine, aspartate and glutamate metabolism, glycine, serine and threonine metabolism, glyoxylate and dicarboxylate acid metabolism. ConclusionMetabolites in serine-related metabolic pathways reduce in serum in MI. We propose a new therapeutic direction for myocardial protection in MI.
HtrA serine peptidase 2 (HTRA2) is a serine protease existing in the mitochondrial gap. Among the four members of the human HtrA serine peptidase family, HTRA2 is the only protease with clear localization in the cell. It plays a dual role in the maintenance of mitochondrial homeostasis and the promotion of cell apoptosis. HTRA2 has been found to be associated with a variety of tumors. Meanwhile, the expression of HTRA2 can enhance the sensitivity of chemotherapy and radiotherapy, and can be used as a diagnostic and prognostic marker for malignant tumors and a target for combined therapy. This article reviews the structure, biological function and role of HTRA2 in malignant tumors, in order to provide clues and basis for early diagnosis and individualized treatment of tumor patients.