Astragalus Polysaccharide Regulates miR-182/Bcl-2 Axis to Relieve Metabolic Memory through Suppressing Mitochondrial Damage-Mediated Apoptosis in Retinal Pigment Epithelial Cells.

INTRODUCTION: Metabolic memory is one of the causes of diabetic retinopathy, and astragalus polysaccharide (APS) has great advantages in the treatment of diabetes. However, the effect of APS on metabolic memory remains to be investigated. METHODS: Retinal pigment epithelial cell line ARPE-19 and primary retinal pigment epithelial cells were used to verify the effect of APS on mitochondria damage and apoptosis induced by high glucose-induced metabolic memory. The relationship between miR-182 and Bcl-2 was confirmed by a luciferase activity assay. Western blotting and quantitative reverse-transcriptase polymerase chain reaction were conducted to investigate the changes in mitochondrial damage- and apoptosis-associated markers. The cell mitochondrial membrane potential was assessed by JC-1 fluorescence. Terminal deoxynucleotidyl transferase dUTP nick end labelling staining and flow cytometry assays were performed to determine the occurrence of apoptosis. RESULTS: Treatment with high glucose followed by normal glucose significantly upregulated the expression of miR-182 and downregulated the expression of its target Bcl-2, and APS treatment reversed the above effects. Additionally, APS treatment restored mitochondrial function and inhibited apoptosis in cells in a state of metabolic memory. The effects of APS against mitochondrial damage and apoptosis were partially inhibited after miR-182 overexpression. CONCLUSION: APS alleviated mitochondrial damage and apoptosis induced by metabolic memory by regulating the miR-182/Bcl-2 axis, which might serve as a new strategy for the treatment of diabetic retinopathy.

miR-30a can inhibit DNA replication by targeting RPA1 thus slowing cancer cell proliferation.

Cell proliferation was inhibited following forced over-expression of miR-30a in the ovary cancer cell line A2780DX5 and the gastric cancer cell line SGC7901R. Interestingly, miR-30a targets the DNA replication protein RPA1, hinders the replication of DNA and induces DNA fragmentation. Furthermore, ataxia telangiectasia mutated (ATM) and checkpoint kinase 2 (CHK2) were phosphorylated after DNA damage, which induced p53 expression, thus triggering the S-phase checkpoint, arresting cell cycle progression and ultimately initiating cancer cell apoptosis. Therefore, forced miR-30a over-expression in cancer cells can be a potential way to inhibit tumour development.

PLAC1 Regulates the Occurrence of Fetal Growth Restriction by Inhibiting the Apoptosis of Trophoblast Cells.

OBJECTIVE: Fetal growth restriction (FGR) refers to impaired and insufficient intrauterine growth potential caused by a variety of adverse factors and is a serious perinatal complication that leads to fetal or neonatal mortality and morbidity. FGR has numerous causes, and its pathogenesis has not been fully understood. Recently, increasing numbers of researchers have begun to focus on the placenta, the only link between the fetus and the mother. The placenta is a vital organ that plays key roles in fetal development. PLAC1 is a trophoblast-specific gene located on the X chromosome and is important for placental development. However, the biological role of PLAC1 in fetal growth restriction is not well understood. In this study, we investigated the changes in the expression of placental-specific protein 1(PLAC1) in the placentas of pregnant women with FGR and in the placentas of normal pregnancies. We also explored the regulation of PLAC1 in the growth of trophoblast cells. METHODS: Western blotting was used to detect the expression of PLAC1 in FGR and in normal placenta tissues. Cell counting kit 8 (CCK-8), wound healing, and transwell assays were used to detect the effects of PLAC1 knockdown on trophoblast cell proliferation, migration, and invasion. Western blotting was used to detect the expression of PLAC1 under hypoxic conditions, and the cell viability and apoptosis of trophoblast cells in a low oxygen concentration after overexpression of PLAC1 were detected by CCK-8 and flow cytometry assay. RESULTS: Compared with the placentas in the control group of normal pregnancies, the expression of PLAC1 in the placentas of the FGR group was significantly down-regulated (p<0.05). Knocking down PLAC1 by siRNA significantly inhibited the proliferation, migration, and invasion of trophoblast cells. After treatment with alow oxygen concentration, the expression of PLAC1 protein was significantly reduced (p<0.05). The overexpression of PLAC1 can reverse the cell viability of trophoblast cells (p<0.05) and inhibit apoptosis of trophoblast cells (p<0.05) in low oxygen concentration. CONCLUSION: The expression of PLAC1 was reduced in fetal growth restriction and did not protect trophoblast cells from hypoxic damage, suggesting that PLAC1 may be an important regulator in the occurrence of fetal growth restriction.

Choriocarcinoma brain metastasis in a patient in the third trimester: a case report.

BACKGROUND: Metastatic choriocarcinoma in the third trimester of pregnancy is extremely rare. CASE PRESENTATION: A 25-year-old Chinese woman (gravida 3, para 0) who was 28 weeks pregnant was admitted for sudden convulsion, aconuresis, and unconsciousness. The decision was made to perform an emergency cesarean delivery and craniotomy, hematoma clearance, and decompression. Pathological examination confirmed choriocarcinoma with brain metastasis. The patient underwent chemotherapy with the etoposide, cisplatin (EP) and etoposide, methotrexate and dactinomycin alternating with cyclophosphamide and vincristine (EMACO) regimens. A satisfactory result was achieved. CONCLUSIONS: When encountering intracranial mass or bilateral pulmonary nodules in a pregnant woman, especially one in the third trimester, metastatic choriocarcinoma should be considered.

CircAPLP2 regulates the proliferation and metastasis of colorectal cancer by targeting miR-101-3p to activate the Notch signalling pathway.

Colorectal cancer (CRC) is one of the most commonly diagnosed cancers, and it has a poor prognosis. Emerging evidence shows that circular RNAs (circRNAs) may act as good therapeutic targets for cancers due to their abundance and stability. However, their regulatory role in CRC needs further investigation. This study revealed that circAPLP2 was upregulated and miR-101-3p was downregulated in CRC tissues and cells compared to normal controls. Knockdown of circAPLP2 and overexpression of miR-101-3p inhibited the cell proliferation, migration and invasion and induced the apoptosis of CRC cells. circAPLP2 acted as a miR-101-3p sponge to upregulate its target gene Notch1, which activated cascades of proliferation- and metastasis-related proteins (c-Myc, cyclin D1, MMP-2 and MMP-9). Additionally, knockdown of circAPLP2 suppressed tumour growth and liver metastases of CRC in nude mice. Taken together, these results indicate that circAPLP2 promotes proliferation and metastasis by targeting miR-101-3p to activate the Notch signalling pathway in CRC, which provides new insights into the mechanisms underlying CRC malignancy and suggests a new therapeutic target.

Carbon dioxide-modified polyethylenimine as a novel gene delivery vector and its in vitro validation.

In this work, the CO2-modified polyethylenimine, as a novel delivery vector, has been validated by combining with the plasmid DNA to form plasmid DNA/CO2-modified polyethylenimine complexes. We have modified polyethylenimine using CO2 to partially convert amine groups to carbamic acid groups. The buffering capacity and the plasmid DNA binding ability of the CO2-modified polyethylenimine and PEI-25 (polyethylenimine with Mw = 25 kDa) were characterized by acid-base titration and agarose gel electrophoresis, respectively. The particle size and zeta potential of the complexes were determined using a Zetasizer Nano ZS. Resistance to nuclease digestion was determined via DNase I protection assay. The cytotoxicity was measured by the MTT assay. The transfection efficiency of the complexes has been evaluated by flow cytometry. It is observed that the condensation capacity of CO2-modified polyethylenimine is still comparable to polyethylenimine and the CO2-modified polyethylenimine can protect plasmid DNA from degradation by DNase I. The diameter of the plasmid DNA/CO2-modified polyethylenimine complex is around 140 nm and the zeta potential decreases. MTT assays confirm that the cytotoxicity is much lower for plasmid DNA/CO2-modified polyethylenimine than for plasmid DNA/PEI-25. The flow cytometry found that in serum-free medium the transfection efficiency can reach a value of ∼60% for plasmid DNA/CO2-modified polyethylenimine, and in 10% fetal bovine serum medium, the transfection efficiency is still as high as ∼40%, which is much higher than that of plasmid DNA/PEI-25. CO2-modified polyethylenimine could be a novel and promising nonviral gene vector for gene therapy.

Electrospun polyvinyl alcohol/carbon dioxide modified polyethyleneimine composite nanofiber scaffolds.

A novel biocompatible polyvinyl alcohol/carbon dioxide modified polyethyleneimine (PVA/PEI-CO2) composite nanofiber was fabricated by a green and facile protocol, which reduces the cytotoxicity of PEI through the surface modification of the PEI with CO2. The (13)C NMR spectrum, elemental analysis, and TGA show that CO2 has been incorporated in the PEI surface resulting in a relatively stable structure. The resulting PVA/PEI-CO2 composite nanofibers have been characterized by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), contact angle, and scanning electron microscopy (SEM). The results show that the average diameters of the nanofibers range from 265 ± 53 nm to 423 ± 80 nm. The cytotoxicity of PVA/PEI-CO2 composite nanofibers was assessed by cytotoxicity evaluation using the growth and cell proliferation of normal mice Schwann cells. SEM and the MTT assay demonstrated the promotion of cell growth and proliferation on the PVA/PEI-CO2 composite scaffold. It suggests that PEI-CO2 can have tremendous potential applications in biological material research.