Co-exposure to multi-walled carbon nanotube and lead ions aggravates hepatotoxicity of nonalcoholic fatty liver via inhibiting AMPK/PPARγ pathway.

Multi-walled carbon nanotubes (MWCNTs) have been widely used in sewage disposal, water purification, and disinfection. Co-exposure to MWCNTs and heavy metal ions is common during water disposal. However, the hepatotoxicity of co-exposure to MWCNTs and lead ions for nonalcoholic fatty liver disease (NAFLD) subjects has not been investigated. NAFLD mice were fed intragastrically with MWCNTs and lead acetate (PbAc). Combined administration of MWCNTs and PbAc significantly damaged the liver function, and aggravated the nonalcoholic steatohepatitis phenotype as well as the hepatic fibrosis and steatosis in NAFLD mice. Furthermore, MWCNTs and PbAc significantly induced apoptosis in primary hepatocytes isolated from NAFLD mice. Combined administration of MWCNTs and PbAc also resulted in hepatic lipid peroxidation by inducing antioxidant defense system dysfunction, and significantly enhanced the expression levels of inflammatory cytokines in NAFLD mice livers. Meanwhile, combined administration of MWCNTs and PbAc may exert its hepatotoxicity in the NAFLD via inhibiting the adenosine 5'-monophosphate activated protein kinase (AMPK)/peroxisome proliferator-activated receptors γ (PPARγ) pathway. Taken together, we conclude that co-exposure to MWCNTs and PbAc can remarkably aggravate the hepatotoxicity in NAFLD mice via inhibiting the AMPK/PPARγ pathway. This study may provide a biosafety evaluation for the application of nanomaterials in wastewater treatment.

Effect of miR-21 on apoptosis in hepatoblastoma cell through activating ASPP2/p38 signaling pathway in vitro and in vivo.

The objective of this study was to investigate the mechanism underlying miR-21-associated apoptosis in HB. In this study, HB and adjacent tissues were collected from patients with HB. RT-PCR, FISH, western blot, apoptosis assay, migration, invasion and wound healing assays, caspase activity assay, luciferase reporter assays, and xenografts mouse model were used to determine the effects of miR-21 on HB cell apoptosis. The results revealed that miR-21 was up-regulated in both HB cell and tissue and was associated with progression of HB. MiR-21 inhibitor enhanced the apoptosis level in HB cells. MiR-21 inhibitor showed reduced abilities of migration and invasion. ASPP2 was a target gene of miR-21. Inhibition of ASPP2 increased abilities of migration and invasion in HB cells. Furthermore, miR-21 inhibitor caused increased activity p-38 signaling. In a xenografts mouse model, miR-21 inhibitor could significantly suppress tumor growth in nude mice along with enhanced expressions of ASPP2 and p38. Taken together, the results suggest that upregulation of miR-21 is related to HB progression and miR-21-associated apoptosis in HB is mediated through ASPP2/p38 signaling pathway in vitro and in vivo. This study provides novel insight into the effects of miR-21 on HB apoptosis and clue to develop new therapies.

Synthesis of Cs3PMo12O40/Bi2O3 composite with highly enhanced photocatalytic activity under visible-light irradiation.

A novel visible-light-active Cs3PMo12O40/Bi2O3 (CsPMo/Bi2O3) composite was prepared by a simple dissolution-precipitation method. The as-prepared samples were characterized by XRD, XPS, FT-IR, SEM, UV-Vis DRS, N2 adsorption-desorption isotherms and electrochemical analysis. The results revealed that Bi2O3 was successfully modified by trace CsPMo. After the addition of H3PMo12O40 acid (HPMo), the surface of Bi2O3 can be roughed. Subsequently, the presence of Cs2CO3 can neutralize the protons of HPMo forming CsPMo precipitate on Bi2O3. Comparing to naked Bi2O3 and CsPMo, the binary composite exhibited many beneficial characteristics in charge generation and separation, such as formation of p-n heterojunction, decreased band gap, enhanced photocurrent response and greatly reduced charge transfer resistance. The photocatalytic activities of the as-prepared samples were evaluated by the degradation of phenol under visible light. The calculated pseudo-first-order rate constants for phenol degradation were 2.7 and 14.8 times relative to that on Bi2O3 and CsPMo, respectively. Dramatically enhanced photocatalytic performance can be observed when the optimal CsPMo/Bi2O3 composite (2.5% CsPMo) was applied. The major active species involved in the degradation process are in the following order: superoxide radical (O2-) > hydroxyl radical (OH) ≈ hole (h+). Besides, the CsPMo/Bi2O3 composite also displayed good stability in cyclic experiments.

MiR-3613-3p affects cell proliferation and cell cycle in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common types of malignant tumors with poor sensitivity to chemotherapy drugs and poor prognosis among patients. In the present study, we downloaded the original data from the Gene Expression Omnibus and compared gene expression profiles of liver cancer cells in patients with HCC with those of colon epithelial cells of healthy controls to identify differentially expressed genes (DEGs). After filtering target microRNAs (miRNA) from core DEGs, we cultured HepG2 cells in vitro, knocked down the miRNA and core mRNAs, and analyzed the effects. We found 228 differentially expressed genes between liver cancer tissue and healthy control tissue. We also integrated the protein-proteininteraction network and module analysis to screen 13 core genes, consisting of 12 up-regulated genes and 1 down-regulated gene. Five core genes were regulated hsa-miR-3613-3p, therefor we hypothesized that hsa-miR-3613-3p was a critical miRNA. After the transfection procedure, we found that changes in hsa-miR-3613-3p were the most obvious. Therefore, we speculated that hsa-miR-3613-3p was a main target miRNA. In addition, we transfected with si (BIRC5, CDK1, NUF2, ZWINT and SPC24), to target genes that can be targeted by miR-3613-3p. Our data shows that BIRC5, NUF2, and SPC24 may be promising liver cancer biomarkers that may not only predict disease occurrence but also potential personalized treatment options.

Facile synthesis of AgI/BiOI-Bi2O3 multi-heterojunctions with high visible light activity for Cr(VI) reduction.

AgI sensitized BiOI-Bi2O3 composite (AgI/BiOI-Bi2O3) with multi-heterojunctions was prepared using simple etching-deposition process. Different characterization techniques were performed to investigate the structural, optical and electrical properties of the as-prepared photocatalysts. It was found that the ternary AgI/BiOI-Bi2O3 composite exhibited: (1) improved photocurrent response, (2) smaller band gap, (3) greatly reduced charge transfer resistance and (4) negative shift of flat band potential, which finally led to easier generation and more efficient separation of photo-generated electron-hole pairs at the hetero-interfaces. Thus, for the reduction of Cr(VI), AgI/BiOI-Bi2O3 exhibited excellent photocatalytic activity under visible light irradiation at near neutral pH. AgI/BiOI-Bi2O3 was optimized when the initial molar ratio of KI to Bi2O3 and AgNO3 to Bi2O3 was 1:1 and 10%, respectively. The estimated kCr(VI) on optimized AgI/BiOI-Bi2O3 was about 16 times that on pure Bi2O3. Good stability was also observed in cyclic runs, indicating that the current multi-heterostructured photocatalyst is highly desirable for the remediation of Cr(VI)-containing wastewater.

MicroRNA-197 inhibits cell proliferation by targeting GAB2 in glioblastoma.

Glioblastoma is the most common type of primary brain tumor in adults, and is usually fatal in a short duration. Acquiring a better understanding of the pathogenic mechanisms of glioblastoma is essential to the design of effective therapeutic strategies. Grb2-associated binding protein 2 (GAB2) is a member of the daughter of sevenless/Gab family of scaffolding adapters, and has been reported to be important in the development and progression of human cancer. Previously, it has been reported that GAB2 is expressed at high levels in glioma, and may serve as a useful prognostic marker for glioma and a novel therapeutic target for glioma invasion intervention. Elucidating why GAB2 is overexpressed in glioma, and investigating how to downregulate it will assist in further understanding the pathogenesis and progression of the disease, and to offer novel targets for therapy. The present study used in situ hybridization to detect microRNA (miR)­197 expression levels and Targetscan to predict that the 3'-UTR of GAB2 was targeted by miR-197. Northern blotting and reverse transcription­quantitative polymerase chain reaction were also conducted in the current study. miR-197 is downregulated in glioblastoma tissues, compared with adjacent normal tissues, however it involvement continues to be detected in the disease. The results of the present study demonstrated that miR­197, as a tumor suppressor gene, inhibited proliferation by regulating GAB2 in glioblastoma cells. Furthermore, GAB2 was not only upregulated in glioma, but its expression levels were also associated with the grades of glioma severity. In addition, overexpression of GAB2 suppressed the expression of miR­197 in glioblastoma cells. Therefore, restoration of miR­197 and targeting GAB2 may be used, in conjunction with other therapies, to prevent the progression of glioblastoma.

Highly enhanced photocatalytic reduction of Cr(VI) on AgI/TiO2 under visible light irradiation: Influence of calcination temperature.

AgI/TiO2 was prepared using a dissolution-precipitation method, followed by calcination at different temperatures (100-700°C). The as-prepared AgI/TiO2 powders were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis-DRS) and electrochemical impedance spectroscopy (EIS). The results revealed that calcination temperature significantly impacted the visible light absorption of AgI/TiO2 along with a shift from metastable γ-AgI to relatively stable ß-AgI. We found that highest photocatalytic reduction rate of Cr(VI) and ß-AgI content were obtained for a calcination temperature of 350°C. Furthermore, the pseudo-first order rate constant was five times that for a photocatalyst calcined at 100°C. The dramatically enhanced reduction rate of Cr(VI) was attributed to enhanced visible light absorption and greatly reduced charge transfer resistance, which eventually facilitates more efficient separation and easier transfer of photogenerated electron-hole pairs to the catalyst surface. Other experimental conditions were also carefully investigated and optimized with initial AgI loading percentage (5%), catalyst dosage (1.0g/L), coexisting organics (1.0mmol/L EDTA) and pH (1-2). The optimal AgI/TiO2 exhibited good stability with little change in activity after 5 cycles.