To investigate the mechanism of renal ischemia-reperfusion injury (IRI) via the regulation of N6-methyl-adenosine (m6A) and relevant genes, IRI was induced in Sprague Dawley rats and the urine and serum creatinine levels and tissue structure changes were observed. m6A and METTL3 protein levels were assessed via dot blotting and western blotting, respectively. The hypoxia/reoxygenation (H/R) cell model was constructed using NRK-52E cells, and METTL3 protein levels were assessed. METTL3 was inhibited to observe its impact on NRK-52E cell apoptosis and m6A expression in H/R processes. Methylated RNA immunoprecipitation (MeRIP) sequencing was conducted, followed by MeRIP-qRT-PCR and qRT-PCR validation. Our results indicated that urine and serum creatinine levels increased and that renal injury and cell apoptosis were both observed in IRI model. In additon, m6A expression increased in the IRI model, and METTL3 protein levels significantly increased in the IRI and H/R models. When METTL3 was inhibited, the m6A levels were accordingly decreased and cell apoptosis was suppressed in the H/R in vitro model. Based on MeRIP sequencing, tfap2a, cyp1b1, and foxd1 were significantly differentially expressed, as was m6A, which is involved in the negative regulation of cell proliferation and kidney development. We confirmed that foxd1 mRNA and its methylation levels contributed to IRI and H/R.

IntroductionHepatocellular carcinoma (HCC) accounts for more than 90% of primary liver cancer. Although great progress has been made on HCC molecular mechanism and therapy techniques, the prognosis of HCC patient is poor due to high metastasis and recurrence.Materials and methodsExpression of miR-542-3p was quantified by quantitative real-time PCR (qRT-PCR). The role of miR-542-3p in HCC metastasis was examined using transwell and 3D-culture assay. qRT-PCR, Western blotting and luciferase reporter assay were used to elucidate the mechanisms of miR-542-3p-mediated cancer metastasis.Results and ConclusionIn the research, we found that miR-542-3p is decreased in HCC cell lines and tissues, and downregulation of miR-542-3p enhances, while upregulation suppresses HCC cell invasion ability. Further assay demonstrated that miR-542-3p can directly target TGF-β1 3′ untranslated region (3′UTR) to influence TGF-β/Smad signaling pathway, and suppression of miR-542-3p can hyperactivate TGF-β/Smad pathway and further to promote Epithelial-Mesenchyme Transition (EMT) and induce poor prognosis. Lastly, the clinical correlation analysis illustrated that miR-542-3p is negatively related with the activity of TGF-β1. In summary, our results find that miR-542-3p takes an important role on HCC progression and provide more evidence of microRNAs (miRNAs) for cancer therapy.

Background Circular RNA (circRNA) is involved in the process of acute kidney injury (AKI), but only a few circRNAs have been reported. In the study, we investigated a new circRNA and its association with AKI. Methods An AKI model was established in Sprague-Dawley rats, followed by serum creatinine and urea nitrogen tests measured by a biochemical analyzer. The pathological changes and apoptosis in the renal tissue were detected by Hematoxylin and Eosin, and TUNEL staining. Then, circRNA expression in AKI was determined by quantitative real-time-PCR (qRT-PCR). NRK-52E cells were induced with hypoxia/reoxygenation (H/R) as in vitro models and the circ-Snrk level was tested by qRT-PCR. The effects of circ-Snrk in H/R-induced NRK-52E cells were assessed by flow cytometry, western blot, and enzyme-linked immunosorbent assay. Finally, RNA sequencing and western blot analysis were used to validate the mRNA profile and pathways involved in circ-Snrk knockdown in H/R-induced NRK-52E. Results A reliable AKI rat model and H/R cell model were established. qRT-PCR demonstrated that circ-Snrk level was upregulated in AKI left kidney tissue and NRK-52E cells with H/R treatment. Circ-Snrk knockdown inhibited apoptosis of NRK-52E cells and secretion of inflammatory factors (IL-6 and TNF-α). RNA sequencing showed that the mRNA profile changed after inhibition of circ-Snrk and differential expression of mRNA mainly enriched various signaling pathways, including MAPK signaling pathway. Furthermore, western blot indicated that circ-Snrk knockdown could inhibit the activation of p-JNK and p-38 transcription factors. Conclusions Circ-Snrk is involved in AKI development and associated with the MAPK signaling pathway in AKI.

BACKGROUND: Broad hemodynamic changes, is believed to have a profoundly damaging effect on donor livers after brain death (DBD) or cardiac death (DCD). It remains unclear whether Doppler ultrasonography (DUS) and contrast-enhanced ultrasonography (CEUS), the imaging modalities to evaluate perfusion, could provide more information of liver discarded. OBJECTIVE: To evaluate the ability of DUS and CEUS to predict the risk of DBD or DCD liver discarded. METHODS: The consecutive DBD or DCD donors with DUS/CEUS examinations before surgical procurement from February 2016 to June 2018 at our institution were included. The US and CEUS images of each donor liver were analyzed and the parameters were recorded. RESULTS: Among the 67 eligible donor livers, 15 (22.4%) were discarded and 52 (77.6%) were used. The discarded livers showed prolonged SAT of hepatic artery (0.08s vs 0.06s, OR = 2.169, P = 0.008) on DUS, less cases with homogeneous enhancement (40.0% vs 73.1%, OR = 0.243, P = 0.028) on CEUS, more cases with decreased enhancement (46.7% vs 15.4%, OR = 4.813, P = 0.011), and less difference of the peak time between portal vein and liver parenchymal (0.5s vs 6.7s, OR = 4.260, P = 0.015). The multivariable analysis showed that donor liver with prolonged SAT of hepatic artery (OR = 7.304, 95% CI: 1.195–44.655, P = 0.031) and decreased enhancement (OR = 2.588, 95% CI: 1.234–5.426, P = 0.012) were independent factors of liver discarded. CONCLUSIONS: DUS/CEUS could be applied as a promising predictive tool to screen high-risk liver donors. The prolonged SAT of hepatic artery on DUS and the decrease of liver donor in enhancement on CEUS, indicating hemodynamic changes in DBD and DCD donor livers, were risk factors of liver discarded.

Renal fibrosis underlies all forms of end-stage kidney disease. Endophilin A2 (EndoA2) plays a role in nephrotic syndrome; however, its effect on renal fibrosis remains unknown. Here, we demonstrate that EndoA2 protects against kidney interstitial fibrosis via the transforming growth factor-β (TGF-β)/Smad signaling pathway. Mouse kidneys with fibrosis or kidney biopsy specimens from patients with fibrotic nephropathy had lower levels of EndoA2 protein expression than that in kidneys without fibrosis. In vivo overexpression of EndoA2 with the endophilin A2 transgene (EndoA2 Tg ) notably prevented renal fibrosis, decreased the protein expression of profibrotic molecules, suppressed tubular injury, and reduced apoptotic tubular cells in the obstructed kidney cortex of mice with unilateral ureteral obstruction (UUO). In vivo and in vitro overexpression of EndoA2 markedly inhibited UUO-or TGF-β1induced phosphorylation of Smad2/3 and tubular epithelial cells dedifferentiation. Furthermore, EndoA2 was coimmunoprecipitated with the type II TGF-β receptor (TβRII), thus inhibiting the binding of the type I TGF-β receptor (TβRI) to TβRII. These findings indicate that EndoA2 mitigates renal fibrosis, at least partially, via modulating the TGF-β/ Smad signaling. Targeting EndoA2 may be a new potential therapeutic strategy for treatment of renal fibrosis.

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