Angiopoietin-like 4 (ANGPTL4) Suppression Ameliorates Lupus Nephritis in MRL/lpr Mice by Inactivating NLRP3 Inflammasome and Inhibiting Inflammatory Response.

Background: Lupus nephritis (LN) refers to the injury caused by systemic lupus erythematosus (SLE) involving the kidneys. A previous study identified angiopoietin-like protein 4 (ANGPTL4) as a novel urinary biomarker for tracking disease activity in LN. Objective: To investigate the detailed role and regulatory mechanism of ANGPTL4 in experimental models of LN. Methods: MRL/lpr mice 11-week-old were injected with adeno-associated virus (AAV)-mediated ANGPTL4 short hairpin RNA (shRNA). At 16 and 20 weeks of age, 24-h urine samples were harvested to measure proteinuria levels. After the mice were sacrificed, blood and kidney tissues were harvested to examine serum creatinine (cr) and blood urea nitrogen (BUN) levels, kidney histological changes, and pro-inflammatory cytokine production. Additionally, the levels of NLRP3 inflammasome-associated molecules in mouse renal tissues were detected to clarify the underlying mechanism. Results: The AAV-sh-ANGPTL4 injection significantly reduced the proteinuria, cr, and BUN levels in MRL/lpr mice. ANGPTL4 silencing ameliorated glomerular, tubular, and interstitial damage in mice, mitigating the pathological alternations of LN. In addition, ANGPTL4 knockdown repressed pro-inflammatory cytokine production in the kidneys. Mechanically, ANGPTL4 suppression inhibited NLRP3 inflammasome expression in renal tissues of mice. Conclusion: ANGPTL4 silencing inhibits the NLRP3 inflammasome-mediated inflammatory response, thereby ameliorating LN in MRL/lpr mice.

Long non-coding RNA Neat1 triggers renal tubular epithelial cell apoptosis via activating BH3-only protein in membranous nephropathy.

BACKGROUND AND OBJECTIVE: Membranous nephropathy (MN) is an autoimmune disease. The up-regulation of the long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1 (Neat1) has been found in MN but the mechanism is still unclear. Here, we explored the effect and the underlying mechanism of lncRNA Neat1 on the apoptosis of renal tubular epithelial cells in MN. METHODS: Albumin-stimulated E11 podocytes and proximal tubular epithelial cells in vitro and the cationic-bovine serum albumin-induced MN mouse model in vivo were established. The expression of Neat1 in E11 podocytes, renal tubular epithelial cells, and renal tubules and the mRNA expression of BH3-only (the Bcl-2 homology 3-only) proteins were determined by quantitative reverse transcription-polymerase chain reaction. Levels of Cleaved Caspase 3, 6, 7, and Noxa were examined by western blotting. The number of apoptotic cells was detected by flow cytometry. Cellular proliferation was determined by 5-Ethynyl-2'-deoxyuridine and Cell Counting Kit-8 assay. Interactions between BH3-only protein Noxa and Bcl-2 as well as Bcl-xL were evaluated with co-immunoprecipitation. RESULTS: The expression of lncRNA Neat1 was unchanged in albumin-stimulated E11 podocytes, but it was up-regulated in albumin-stimulated renal tubular epithelial cells and MN renal tubule tissues and there was a time-dependent increase in vivo. In the albumin-stimulated proximal tubular epithelial cells, overexpression of Neat1 could increase apoptosis and decrease proliferation. In turn, interference with Neat1 reduced apoptosis and increased proliferation accordingly. The mRNA expression levels of BH3-only proteins (Bad, Bim, Bid, Puma, Noxa) were detected with qRT-PCR, the results indicated that after overexpression of Neat1, mRNA and protein levels of Noxa were significantly increased, and the interference with BH3-only protein Noxa alleviated apoptosis of renal tubular epithelial cells in vitro. CONCLUSION: In our study, we proved that lncRNA Neat1 promoted the development of MN by inducing apoptosis and this effect may be exerted by inhibiting the anti-apoptotic protein activity mediated by Noxa.

[Identification of critical influencing factors in dropping process of Xuesaitong Dropping Pills].

With the dropping process of Xuesaitong Dropping Pills(XDP) as the study object, critical factors affecting the quality indicators of pill pass rate, average weight of drop pills and roundness were screened out, so as to deepen the understanding of the dropping process. The critical process units, critical quality attributes and potential critical process influencing factors of XDP were determined by risk analysis and prior knowledge, and then the critical influencing factors were screened out by Plackett-Burman design. First, according to the risk assessment, the critical technique of XDP preparation process was dropping, and then the critical quality attributes of dropping process were pill pass rate, average weight of drop pills and roundness. Then, according to fishbone diagram and failure mode and effects analysis(FMEA), potential critical influencing factors were determined as flow rate, matrix ratio, solid-liquid ratio, feed-liquid temperature, top temperature of condensate, bottom temperature of condensate and dropping distance. Finally, among these seven potential factors, the critical influencing factors were determined as material liquid ratio, dropping distance, top temperature of condensate, bottom temperature of condensate. This study revealed the potential of Plackett-Burman design in screening and understanding the influence of selected factors on XDP dropping process, which could provide a reference for studying the dropping process.

Clinical characteristics of patients with uremia undergoing maintenance hemodialysis complicated with COVID-19.

This study aimed to evaluate the onset characteristics of patients with uremia undergoing maintenance hemodialysis complicated with COVID-19, so as to improve the understanding, diagnosis, and treatment.26 cases were confirmed cases of COVID-19. Confirmed patients with COVID-19 undergoing maintenance hemodialysis in the blood purification center were recruited. The general data of patients, including age, sex, duration of dialysis, and basic diseases, were analyzed. The clinical features included fever, respiratory symptoms, and gastrointestinal symptoms. The items for laboratory tests included blood routine examination, liver function, C-reactive protein, procalcitonin, creatine kinase, creatine kinase-MB, markers of myocardial injury, B-type natriuretic peptide, D-dimer, and so forth. The imaging examinations referred mainly to computed tomography imaging findings of the lungs.Twenty-one cases were complicated with chronic basic diseases, such as hypertension or diabetes. In terms of clinical manifestations, 13 cases had fever, which was close to the number of cases without fever (13 cases). The respiratory symptoms included dry cough (19 cases), shortness of breath (9 cases), fatigue (11 cases), and so forth. Further, 15 patients had hypoxemia, indicating more severe patients. Sore throat (2 cases) was not significant, and a few patients reported gastrointestinal symptoms (3 cases). The results of blood routine examination showed decreased absolute lymphocyte count (0.7 ±â€Š0.4 × 10∼9/L), lower hemoglobin level (105.2 ±â€Š20 g/L), and normal absolute neutrophil count 4.2 (3.0, 5.9) × 10∼9/L. Of the inflammatory indexes, procalcitonin was 0.69 (0.24, 2.73) ng/mL; C reactive protein was 17.2 (5.2, 181.6) mg/L, which was higher than normal. Blood biochemistry revealed lower albumin level (38.0 ±â€Š4.0 g/L) and higher troponin 0.11(0.035, 6.658) ng/mL and myoglobin levels (538.5 ±â€Š240.5 ng/mL), suggesting myocardial injury.The patients with uremia and confirmed COVID-19 undergoing maintenance hemodialysis are more common in males. Although the proportion of fever patients is 50%, the proportion of hypoxemia patients is high (58%). With poor cardiac function. They were prone to respiratory failure complicated with heart failure. According to the onset characteristics of this population, early diagnosis and treatment could help reduce the risk of developing a critical illness and control the spread of the COVID-19 epidemic.

Up-regulation of miR-135b expression induced by oxidative stress promotes the apoptosis of renal tubular epithelial cells under high glucose condition.

This study aimed to investigate the role and underlying mechanism of miR-135b in high glucose-induced oxidative stress of renal tubular epithelial cells. Here, in vivo experiments found that compared to the control group, miR-135b expression was significantly up-regulated in the diabetes group, whereas BMP7 mRNA and protein levels were down-regulated. In high glucose-treated renal tubular epithelial cells (HK-2) in vitro, oxidative stress was induced, which up-regulated miR-135b expression. In addition, the regulation of miR-135b on BMP7 expression was confirmed in HK-2 cells. Under high glucose conditions, oxidative stress promoted the apoptosis of HK-2 cells through the up-regulation of miR-135b expression. In vivo experiments indicated that interference with miR-135b improved renal function in mice with diabetic nephropathy. In conclusion, these results indicated that the up-regulation of miR-135b expression induced by oxidative stress promotes the apoptosis of HK-2 cells under high glucose conditions.

Modulation of caspase activation and p27(Kip1) degradation in the p53-induced apoptosis in IW32 erythroleukemia cells.

To examine the p53-mediated biological activities and signalling pathways, we generated stable transfectants of the p53-null IW32 murine erythroleukemia cells expressing the temperature-sensitive p53 mutant DNA, tsp53(val135). Two clones with different levels of p53 protein expression were selected for further characterization. At permissive temperature, clone 1-5 cells differentiated along the erythroid pathway, and clone 3-2 cells that produced greater levels (3.5-fold) of p53 underwent apoptosis. Apoptosis of 3-2 cells was accompanied by mitochondrial cytochrome c release and caspase activation as well as by cleavage of caspase substrates. Bax protein was induced to a similar extent in these clones by wild-type p53; expression of p21(Cip1/Waf1) and p27(Kip1) proteins was also increased. However, significantly lesser extent of induction for both CDK inhibitors was detected in the apoptotic 3-2 clone. The general caspase inhibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone (z-VAD.fmk) blocked the p53-induced apoptosis in 3-2 cells, with a concomitant elevation of p27(Kip1), suggesting that p27(Kip1) protein underwent caspase-dependent proteolysis in the apoptotic 3-2 cells. Together these results linked a pathway involving cytochrome c release, caspase activation and p27(Kip1) degradation to the p53-induced apoptosis in IW32 erythroleukemia cells.