AGE receptor 1 silencing enhances advanced oxidative protein product-induced epithelial-to-mesenchymal transition of human kidney proximal tubular epithelial cells via RAGE activation.

Advanced oxidative protein products (AOPPs) are novel uremic toxins whose concentrations continuously increases in patients with chronic kidney disease (CKD). Epithelial-to-mesenchymal transition (EMT) of tubular cells is the main mechanism underlying CKD pathogenesis. Studies have shown that AOPPs can induce EMT and promote renal fibrosis. However, the mechanism through which AOPPs induce tubular cell-EMT is poorly understood. In this study, we aimed to clarify the mechanisms underlying AOPP-induced EMT in human kidney proximal tubular (HKC-8) epithelial cells. Small molecule inhibitor, CRISPR-Cas9 knockout technology, siRNA knockdown technology, western blot, and reverse transcription-quantitative polymerase chain reaction were applied to investigate the mechanisms underlying AOPP-induced EMT in HKC-8 cells. AOPP treatment was found to significantly induce EMT, as evidenced by increased α-smooth muscle actin (α-SMA) and decreased E-cadherin levels, and upregulated Wnt1, ß-catenin, Tcf4, and Gsk-3ß expression. Conversely, blockade of Wnt/ß-catenin signaling using small molecule inhibitor ICG-001 hindered AOPP-induced EMT. Moreover, knockout of receptor of advanced glycation end-products (RAGE) reversed these aforementioned effects, whereas AGE receptor 1 (AGER1)-specific siRNA transfection enhanced them. Taken together, these data suggested that AOPPs could induce HKC-8 cell EMT by activating the RAGE/Wnt/ß-catenin signaling pathway and AGER1 could restore EMT by antagonizing the role of RAGE. These results may provide a new theoretical basis for EMT and help identify new therapeutic targets for suppressing CKD progression.

Preparation of Polyoxymethylene/Exfoliated Molybdenum Disulfide Nanocomposite through Solid-State Shear Milling.

In this paper, the solid-state shear milling (S3M) strategy featuring a very strong three-dimensional shear stress field was adopted to prepare the high-performance polyoxymethylene (POM)/molybdenum disulfide (MoS2) functional nanocomposite. The transmission electron microscope and Raman measurement results confirmed that the bulk MoS2 particle was successfully exfoliated into few-layer MoS2 nanoplatelets by the above simple S3M physical method. The polarized optical microscope (PLM) observation indicated the pan-milled nanoscale MoS2 particles presented a better dispersion performance in the POM matrix. The results of the tribological test indicated that the incorporation of MoS2 could substantially improve the wear resistance performance of POM. Moreover, the pan-milled exfoliated MoS2 nanosheets could further substantially decrease the friction coefficient of POM. Scanning electron microscope observations on the worn scar revealed the tribological mechanism of the POM/MoS2 nanocomposite prepared by solid-state shear milling. The tensile test results showed that the pan-milled POM/MoS2 nanocomposite has much higher elongation at break than the conventionally melt-compounded material. The solid-state shear milling strategy shows a promising prospect in the preparation of functional nanocomposite with excellent comprehensive performance at a large scale.

LncRNA CARMN Affects Hepatocellular Carcinoma Prognosis by Regulating the miR-192-5p/LOXL2 Axis.

Background: Hepatocellular carcinoma (HCC) is aggressive cancer with a poor prognosis. It has been suggested that the aberrant expression of LOXL2 is associated with the development of HCC, but the exact mechanism remains unclear. This research is aimed at examining the expression level and prognostic value of LOXL2 in hepatocellular carcinoma and its relationship with immune infiltration and at predicting its upstream noncoding RNAs (ncRNAs). Method: The transcriptome data of HCC was first downloaded from The Cancer Genome Atlas (TCGA) database to investigate the expression and prognosis of LOXL2. Then, the starBase database was used to find the upstream ncRNAs of LOXL2, and correlation analysis and expression analysis were performed. Finally, the Tumor Immune Estimation Resource (TIMER) was used to explore the association between LOXL2 and immune cell infiltration. Result: CARMN was considered to be the potential upstream lncRNA for the hsa-miR-192-5p/LOXL2 axis in HCC. Furthermore, the level LOXL2 was markedly positively associated with tumor immune cell infiltration and immune checkpoint expression in HCC. Conclusion: Higher expression of LOXL2 mediated by microRNA (miRNA) and long noncoding RNAs (lncRNA) is associated with poor overall survival (OS), immune infiltration, and immune checkpoint expression in HCC.

Effect of total glucosides of paeony and Tripterygium wilfordii polyglycosides on erythrocyte methotrexate polyglutamates in rats, analysed using ultra-high-performance liquid chromatography-tandem mass spectrometry.

OBJECTIVES: The aim of the study was to explore the effect of total glucosides of paeony (TGP) and Tripterygium wilfordii polyglycosides (TWP) on erythrocyte methotrexate polyglutamates (MTXPGs), the metabolites of methotrexate (MTX). METHODS: An ultra-high-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS) method was developed to determine MTXPGs. The effects of MTXPGs were analysed using 24 male Sprague-Dawley rats that were randomly divided into the MTX alone, MTX-TGP combined, and MTX-TWP combined groups. Rats were administered MTX at a dose of 0.9 mg/kg once a week, TGP at 0.054 g/kg and TWP at 1.8 mg/kg three times a day. Venous blood (1.0 ml) was collected at weeks 2, 4, 6, 9, 12 and 15 and then analysed using the developed UPLC-MS/MS method. KEY FINDINGS: Specificity, linear range, inter-and intra-day precision, recovery, matrix effect and stability of MTXPGs met the standard regulations. This method was successfully used for the detection of MTXPGs. After administration of MTX alone, erythrocyte MTXPGs increased and accumulated in a time- and dose-dependent manner. Compared to MTX alone, the combination with TGP significantly decreased the content of total MTXPGs and short-chain MTXPGs (Methotrexate [MTX/MTXPG1] and 4-amino-10-methylpteroyldiglutamic acid [MTXPG2], P < 0.05), but had no significant effect on long-chain MTXPGs (4-amino-10-methylpteroyltriglutamic acid [MTXPG3], P > 0.05) and very long-chain MTXPGs (4-amino-10-methylpteroyltetraglutamic acid [MTXPG4] and 4-amino-10-methylpteroylpentaglutamic acid [MTXPG5], P > 0.05) at week 15. The combination of MTX with TWP had no significant effect on the content of total MTXPGs, short-chain MTXPGs and long-chain MTXPGs (P > 0.05), but it significantly decreased the content of very long-chain MTXPGs (P < 0.05) at week 15. CONCLUSIONS: The UPLC-MS/MS method was successfully used to determine MTXPGs in rat erythrocytes. TGP and TWP in combination with MTX affected the production of MTXPGs of different chain lengths in erythrocytes.

[Interaction between atorvastatin and voriconazole in rat plasma: a HPLC-MS/MS-based study].

OBJECTIVE: To develop a high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for simultaneous determination of atorvastatin and voriconazole in rat plasma and investigate the pharmacokinetics of atorvastatin and the changes in voriconazole concentration in rats after administration. METHODS: Plasma samples were collected from rats after intragastric administration of atorvastatin alone or in combination with voriconazole. The samples were treated with sodium acetate acidification, and atorvastatin and voriconazole in the plasma were extracted using a liquidliquid extraction method with methyl tert-butyl ether as the extractant. The extracts were then separated on a Thermo Hypersil Gold C18 (2.1×100 mm, 1.9 µm) column within 6 min with gradient elution using acetonitrile and water (containing 0.1% formic acid) as the mobile phase; mass spectrometry detection was achieved in selective reaction monitoring (SRM) mode under the positive ion scanning mode of heated electrospray ion source (H-ESI) and using transition mass of m/z 559.2→440.2 for atorvastatin and m/z 350→280 for voriconazole, with m/z370.2→252 for lansoprazole (the internal standard) as the quantitative ion. RESULTS: The calibration curves were linear within the concentration range of 0.01-100 ng/mL (r=0.9957) for atorvastatin and 0.025-100 ng/mL (r=0.9966) for voriconazole. The intra-day and inter-day precisions were all less than 13%, and the recovery was between 66.50% and 82.67%; the stability of the plasma samples met the requirements of testing. The AUC0-24 h of atorvastatin in rat plasma after single and combined administration was 438.78±139.61 and 927.43±204.12 h·µg·L-1, CLz/F was 23.89±8.14 and 10.43±2.58 L·h-1·kg-1, Cmax was 149.62±131.10 and 159.37±36.83 µg/L, t1/2 was 5.08±1.63 and (5.58±2.11 h, and Tmax was 0.37±0.14 and 3.60±1.52 h, respectively; AUC0-24 h, CLZ/F and Tmax of atorvastatin in rat plasma differed significantly between single and combined administration. The HPLC-MS/MS system also allowed simultaneous determination of voriconazole concentration in rat plasma after combined administration. CONCLUSIONS: The HPLC-MS/MS system we established in this study is simple, rapid and sensitive and allows simultaneous determination of atorvastatin and voriconazole in rat plasma. Some pharmacokinetic parameters of atorvastatin are changed in the presence of voriconazole, and their clinical significance needs further investigation.