Lysine-specific demethylase 1 aggravated oxidative stress and ferroptosis induced by renal ischemia and reperfusion injury through activation of TLR4/NOX4 pathway in mice.

Acute kidney injury (AKI) is mainly caused by renal ischaemia reperfusion injury (IRI). Lots of evidence suggests that ferroptosis and oxidative stress play the vital role in renal IRI. However, the specific mechanism of renal IRI has not been fully elucidated. lysine-specific demethylase 1 (LSD1) has been shown to regulate the pathogenesis of kidney disease. In this study, we firstly found that LSD1 was positively related to renal IRI. TCP, a classical LSD1 inhibitor, could alleviate tissue damage induced by renal IRI. Inhibition of LSD1 with either TCP or LSD1 knockdown could alleviate ferroptosis and oxidative stress caused by IRI both in vivo and in vitro. Furthermore, the results showed that suppression of LSD1 decreased the expression of TLR4/NOX4 pathway in HK-2 cells subjected to H/R. With the si-RNA against TLR4 or NOX4, it showed that the silence of TLR4/NOX4 reduced oxidative stress and ferroptosis in vitro. Moreover, to demonstrate the crucial role of TLR4/NOX4, TLR4 reduction, mediated by inhibition of LSD1, was compensated through delivering the adenovirus carrying TLR4 in vitro. The results showed that the compensation of TLR4 blunted the alleviation of oxidative stress and ferroptosis, induced by LSD1 inhibition. Further study showed that LSD1 activates TLR4/NOX4 pathway by reducing the enrichment of H3K9me2 in the TLR4 promoter region. In conclusion, our results demonstrated that LSD1 inhibition blocked ferroptosis and oxidative stress caused by renal IRI through the TLR4/NOX4 pathway, indicating that LSD1 could be a potential therapeutic target for renal IRI.

A prognosis model for clear cell renal cell carcinoma based on four necroptosis-related genes.

Necroptosis is a type of caspase-independent cell death, and it plays a critical role in regulating the development of cancer. To date, little is known about the role of necroptosis-related genes (NRGs) in clear cell renal cell carcinoma (ccRCC). In this study, we downloaded data regarding the expression of NRGs and overall survival (OS) from The Cancer Genome Atlas (TCGA) database and constructed a risk model to determine the prognostic features of necroptosis using COX regression analysis. Patients with ccRCC were divided into low-risk and high-risk groups based on their risk scores. Thereafter, Kaplan-Meier curves were used to evaluate OS, and receiver operating characteristic (ROC) curves were used to determine the accuracy of prediction. Stratified analyses were performed according to different clinical variables. Furthermore, we assessed the correlation between clinical variables and risk scores; the NRGs with differential expression were mainly enriched in positive regulation of intracellular transport and platinum resistance pathways. We constructed prognostic signatures for OS based on four NRGs and showed that the survival time was significantly longer in the low-risk groups than in the high-risk groups (p < 0.001). The area of the ROC curve for OS was 0.717, indicating excellent predictive accuracy of the established model. Therefore, a predictive model based on NRGs was constructed, which can predict the prognosis of patients and provides insights into the biological mechanisms underlying necroptosis in patients with ccRCC.

[Effects of hydrodynamics-mediated RNAi on Mfn2 expression, blood sugar and fat levels in mice].

OBJECTIVE: To investigate the effects of hydrodynamics-mediated RNAi for Mfn2 gene expression in liver and the levels of blood sugar and fat in mice. METHODS: Fifty-six male BALB/c mice were randomly divided into normal control group (NC, n = 8), negative control group (HK, n = 24) and transfection group (Mfn2, n = 24) according to random digits table. 1.5 ml plasmid (negative control or Mfn2 shRNA, 75mug for each mouse) diluted into phosphate buffered solution (PBS) was injected into the HK and Mfn2 groups mice via hydrodynamic intravascular injection. Mfn2 mRNA and protein expression in hepatic tissue was detected by RT-PCR and Western-blot 24 hours, 72 hours and 120 hours respectively after injection. At the same time, the levels of fasted blood sugar (FBS) and triglyceride (TG) were measured. RESULTS: Compared with HK mice, the expressions of Mfn2 mRNA (1.00+/-0.03 vs 1.14+/-0.07, t = 4.027, P = 0.007; 1.01+/-0.053 vs 1.18+/-0.07, t = 4.234, P = 0.006) and protein (7.81+/-0.80 vs 8.01+/-0.08, t = 2.941, P = 0.042; 8.05+/-0.15 vs 8.56+/-0.014, t = 4.883, P = 0.039) decreased markedly in Mfn2 mice in 72 and 120 hours after injection. In the fasting state, in 24 hours after injection, FBS in Mfn2 group was significantly lower than that in HK group [(2.65+/-0.70 vs 5.28+/-0.82) mmol/L, t = 6.879, P value less than 0.01] and TG was also significantly higher than that in HK group [(1.96+/-0.32 vs 1.12+/-0.16) mmol/L, t = -6.711, P value less than 0.01]. No statistical differences found between the NC and HK groups for FBS and TG (F = 1.412, P = 0.26; F = 2.711, P = 0.14). The plasma glucose level in Mfn2 mice was significantly higher than that in HK mice [(7.23+/-0.82 vs 5.18+/-0.69) mmol/L, t = 2.050, P value less than 0.01; (7.00+/-0.67 vs 6.05+/-0.76) mmol/L, t = 3.57, P = 0.023] in 72 and 120 hours after injection. However, no differences found between the two groups for blood TG [(1.53+/-0.27 vs 1.37+/-0.18) mmol/L, t = 0.160, P = 0.23; (1.84+/-0.30 vs 1.52+/-0.37) mmol/L, t = 0.330, P = 0.503]. CONCLUSION: The data indicate that hydrodynamics- mediated RNAi for Mfn2 gene can effectively inhibit the expression of target gene in mice liver in 72 and 120 hours after shRNA administration, and the inhibition of hepatic Mfn2 can induce glycometabolic and fat metabolic disorder.

A hospital-wide reduction in central line-associated bloodstream infections through systematic quality improvement initiative and multidisciplinary teamwork.

BACKGROUND: Few data are available on hospital-wide incidence of central line-associated bloodstream infection (CLABSI) rates in patients with central venous catheter (CVC) in China, where many systemic obstacles holding back evidence-based guidelines implementation exist. METHODS: This study was conducted prospectively in 2 phases. The baseline and intervention phases were performed in a teaching hospital in China, between January 2017 and October 2018. A systematic quality improvement (SQI) and multidisciplinary teamwork (MDT) CLABSI infection control program was introduced in the intervention phase. In the intensive care units (ICUs) and non-ICUs, CLABSIs were continuously monitored, data collected, then analyzed. RESULTS: After intervention, the CLABSI rate decreased from 2.84-0.56 per 1,000 CVC days in ICUs (P < .001), and from 0.82-0.47 per 1,000 CVC days in non-ICUs (P = .003). The length of time until CLABSI occurrence increased from 8.72-13.60 days in ICUs (P = .046), and from 10.00-12.00 days in non-ICUs (P = .048). The number of multidrug-resistant bacteria isolated from CLABSI episodes decreased both in ICUs and in non-ICUs. CONCLUSIONS: The SQI and MDT CLABSI infection control program is effective in reducing hospital-wide CLABSI in patients with CVC, both in ICUs and in non-ICUs.