Roxadustat protects rat renal tubular epithelial cells from hypoxia-induced injury through the TGF-ß1/Smad3 signaling pathway.

OBJECTIVE: Roxadustat is used to treat renal anemia. The renoprotective effect of roxadustat needs to be further confirmed, and the mechanism of action is unknown. This study aims to evaluate the effect and mechanism of roxadustat in hypoxia-related nephropathy with the renal tubular epithelial cell line NRK-52E. MATERIALS AND METHODS: The cell Counting Kit-8 (CCK-8) assay was employed to assess cellular proliferation in the current investigation. Flow cytometry was used to conduct cell apoptosis analysis. The utilization of electron microscopy facilitated the identification of changes in cellular ultrastructure. Immunofluorescence was used to detect the expression trend of hypoxia-inducible factor-1α (HIF-1α). The connective tissue growth factor (CTGF), transforming growth factor-ß1 (TGF-ß1), Smad family member 3 (Smad3), p-Smad3, α-smooth muscle actin (α-SMA), collagen I, and HIF-1α were assessed by western blotting. Real-time fluorescent quantitative PCR (RT-qPCR) was used to measure TGF-ß1 and Smad3 mRNA. RESULTS: Significant growth inhibition and increased apoptosis were observed in NRK-52E cells cultured under hypoxic conditions (1% and 5% O2), which can be rescued by roxadustat. From a morphological perspective, it has been observed that roxadustat can counteract cellular damage features produced by hypoxia. These features include the contraction of the nuclear envelope and an increase in the formation of apoptotic bodies. Roxadustat increases HIF-1α expression acutely at 24 h, followed by a gradual reduction of HIF-1α expression to levels significantly below that of the hypoxia group by 72 h. Roxadustat can also inhibit hypoxia-induced increased expression of CTGF, TGF-ß1, p-Smad3, α-SMA, collagen I, and HIF-1α. Combined treatment with roxadustat and siRNA against TGF-ß1 synergistically reduced the expression of CTGF and HIF-1α, while the effect on TGF-ß1 and p-Smad3 were comparable to that of the individual treatment alone. Comparably, the combined administration of roxadustat and siRNA targeting Smad3 had a synergistic impact on diminishing the expression of CTGF. CONCLUSIONS: These findings indicate that roxadustat attenuates experimental renal fibrosis likely by inhibiting the TGF-ß1/Smad3 pathways, while its effect on CTGF and HIF-1α may involve other signaling pathways.

[Clinical application and research progress of balloon-occluded retrograde transvenous obliteration in the treatment of gastric varices with decompensated liver cirrhosis].

Gastric varices are one of the serious complications of liver cirrhotic portal hypertension. Balloon-occluded retrograde transvenous obliteration (BRTO), as an interventional treatment method, can effectively prevent and control gastroesophagel variceal bleeding. Simultaneously, it has an obvious effect in the treatment of hepatic encephalopathy and liver function improvement. This article reviews the clinical application and research progress of BRTO at home and abroad in recent years, with a view to provide reference for clinical treatment.

Characterization of SNPs in strawberry cultivars in China.

Single nucleotide polymorphisms (SNPs) occur at high frequencies in both plant and animal genomes and can provide broad genome coverage and reliable estimates of genetic relationships. The availability of expressed sequence tag (EST) data has made it feasible to discover SNPs. DNA analysis is crucial in genetic studies not only for strawberry breeding programs but also for characterization of hybrids and species. We cloned 96 EST sequences, and 116 SNPs were discovered by comparing 16 strawberry cultivars grown in the region of Nanjing, China. Sequence alignment of 6 group sequences derived from 16 sample cultivars yielded 116 SNPs, within a total genomic sequence length of 1755 bp. The SNPs were discovered with a mean frequency of one SNP per 15 bp. These SNPs were comprised of 57% transitions, 32.7% transversions, 8.6% InDels, and 1.7% others, based on which a phylogenetic tree was constructed. Among the 116 SNPs, 75% were located within the open reading frame (ORF), while 25% were located outside the ORF. All 16 cultivars scattered well in dendrogram derived from the SNP data, demonstrating that SNPs can be a powerful tool for cultivar identification and genetic diversity analysis in strawberries.

Biodegradable CaMgZn bulk metallic glass for potential skeletal application.

A low density and high strength alloy, Ca65Mg15Zn20 bulk metallic glass (CaMgZn BMG), was evaluated by both in vitro tests on ion release and cytotoxicity and in vivo implantation, aimed at exploring the feasibility of this new biodegradable metallic material for potential skeletal applications. MTT assay results showed that the experimental CaMgZn BMG extracts had no detectable cytotoxic effects on L929, VSMC and ECV304 cells over a wide range of concentrations (0-50%), whereas for MG63 cells concentrations in the range ~5-20% promoted cell viability. Meanwhile, alkaline phosphatase (ALP) activity results showed that CaMgZn BMG extracts increased alkaline phosphatase (ALP) production by MG63 cells. However, Annexin V-fluorescein isothiocyanate and propidium iodide staining indicated that higher concentrations (50%) might induce cell apoptosis. The fluorescence observation of F-actin and nuclei in MG63 cells showed that cells incubated with lower concentrations (0-50%) displayed no significant change in morphology compared with a negative control. Tumor necrosis factor-α expression by Raw264.7 cells in the presence of CaMgZn BMG extract was significantly lower than that of the positive and negative controls. Animal tests proved that there was no obvious inflammation reaction at the implantation site and CaMgZn BMG implants did not result in animal death. The cortical thickness around the CaMgZn BMG implant increased gradually from 1 to 4 weeks, as measured by in vivo micro-computer tomography.

[Experimental study of protective effect of tongxinluo capsule on isoproterenol induced myocardial injury in rats].

OBJECTIVE: To study the protective effect of Tongxinluo capsule (TXLC) on myocardial injury induced by isoproternol. METHODS: Myocardial injury was induced in 34 rats by subcutaneous injection of isoproterenol (85 mg/kg). The experimental animals were randomly divided into the control group, isoproterenol group and TXLC group. The histopathological change of myocardia was investigated by HE staining, the myocardial cell apoptosis were observed by TUNEL method and the ultrastructure of myocardial cell examined by electron microscope. RESULTS: No cell degeneration and necrosis, only very few cells of apoptosis positive were found in the control group. While in the isoproterenol group, marked necrosis of myocardial tissue and increase of apoptosis cells were found, and characteristic changes of cell apoptosis were observed under electron microscope. After TXLC treatment, the myocardial necrosis and cell apoptosis were markedly alleviated. CONCLUSION: Isoproterenol could induce myocardial necrosis and apoptosis, TXLC could alleviate the myocardial injury through preventing myocardial cell necrosis and apoptosis.

Voltammetric studies of the effect of Cisplatin-liposome on Hela cells.

In this paper, the voltammetric method was used for the first time to study the effect of Cisplatin-liposome on Hela cells. The results showed the voltammetric behavior of Hela cells was irreversible and the peak current had linear relationship with the cell number. With both Cisplatin-liposome concentration and treating time increasing, the peak current decreased. The peak current decreasing was in accordance with the nuclear damage and loss of mitochondrial membrane potential revealed by two-photon laser scanning microscopy and confocal laser scanning microscopy. This voltammetric method may provide a simple way to study the electron-transfer mechanism in drug-treating cells.

Electrochemical immunoassay based on catalytic conversion of substrate by labeled metal ion and polarographic detection of the product generated.

In a new electrochemical immunoassay based on the conversion of a substrate catalyzed by a labeled metal ion and the polarographic detection of the product generated, metal copper ion was used to label model antigen human serum albumin through the bifunctional chelating agent diethylenetriaminepentaacetic acid. After heterogeneous competitive immunoreaction, the labeled copper ion was released or activated by acidification and chemically catalyzed the conversion of the substrate o-phenylenediamine to the electroactive product 2,3-diaminophenazine (DAP). The DAP was quantified using linear-potential scan polarography. The sensitivity of the proposed assay was 100 times higher than that of the previous methods based on direct detection of the metal ion labels. This immunoassay can be used to detect any protein of interest.