Mipu1 protects H9c2 myogenic cells from hydrogen peroxide-induced apoptosis through inhibition of the expression of the death receptor Fas

ZNF667 facilitates angiogenesis after myocardial ischemia through transcriptional regulation of VASH1 and Wnt signaling pathway

Zinc finger protein 667 (ZNF667, also referred as Mipu1), a widely expressed KRAB/C₂H₂-type zinc finger transcription factor, can protect against hypoxic-ischemic myocardial injury. Pro-angiogenesis is regarded as a promising strategy for the treatment of acute myocardial infarction (AMI). However, whether ZNF667 is involved in the angiogenesis following AMI remains to be elucidated. The present study reported that the expression of ZNF667 in CD31-positive endothelial cells (ECs) was upregulated in the heart of AMI mice. Hypoxic challenge (1% oxygen) promoted the mRNA and protein expression of ZNF667 in the human umbilical vein endothelial cells (HUVECs) in a time-dependent manner. Moreover, ZNF667 promoted hypoxia-induced invasion and tube formation of HUVECs. Mechanically, ZNF667 could directly bind to the promoter of anti-angiogenic gene VASH1 and inhibit its expression. Consequently, VASH1 overexpression abolished hypoxic challenge or ZNF667 overexpression-induced invasion and tube formation of HUVECs. Further bioinformatic analyses suggested that overexpression of ZNF667 or knockdown of VASH1-induced differentially expressed genes in HUVECs were greatly enriched in the Wnt signaling pathway (DAAM1, LEF1, RAC2, FRAT1, NFATc2 and WNT5A). Together, these data suggested that ZNF667 facilitates myocardial ischemia-driven angiogenesis through transcriptional repression of VASH1 and regulation of Wnt signaling pathway.

Angiotensin II induces reactive oxygen species, DNA damage, and T cell apoptosis in severe COVID-19

Background

Lymphopenia is predictive of survival in patients with coronavirus disease 2019 (COVID-19).

Objective

The aim of this study was to understand the cause of the lymphocyte count drop in severe forms of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

Methods

Monocytic production of reactive oxygen species (ROSs) and T-cell apoptosis were measured by flow cytometry, DNA damage in PBMCs was measured by immunofluorescence, and angiotensin II (AngII) was measured by ELISA in patients infected with SARS-CoV-2 at admission to an intensive care unit (ICU) (n = 29) or not admitted to an ICU (n = 29) and in age- and sex-matched healthy controls.

Results

We showed that the monocytes of certain patients with COVID-19 spontaneously released ROSs able to induce DNA damage and apoptosis in neighboring cells. Of note, high ROS production was predictive of death in ICU patients. Accordingly, in most patients, we observed the presence of DNA damage in up to 50% of their PBMCs and T-cell apoptosis. Moreover, the intensity of this DNA damage was linked to lymphopenia. SARS-CoV-2 is known to induce the internalization of its receptor, angiotensin-converting enzyme 2, which is a protease capable of catabolizing AngII. Accordingly, in certain patients with COVID-19 we observed high plasma levels of AngII. When looking for the stimulus responsible for their monocytic ROS production, we revealed that AngII triggers ROS production by monocytes via angiotensin receptor I. ROSs released by AngII-activated monocytes induced DNA damage and apoptosis in neighboring lymphocytes.

Conclusion

We conclude that T-cell apoptosis provoked via DNA damage due to the release of monocytic ROSs could play a major role in COVID-19 pathogenesis.

Taurine Increases Zinc Preconditioning-Induced Prevention of Nitrosative Stress, Metabolic Alterations, and Motor Deficits in Young Rats following Intrauterine Ischemia

Oxygen deprivation in newborns leads to hypoxic-ischemic encephalopathy, whose hallmarks are oxidative/nitrosative stress, energetic metabolism alterations, nutrient deficiency, and motor behavior disability. Zinc and taurine are known to protect against hypoxic-ischemic brain damage in adults and neonates. However, the combined effect of prophylactic zinc administration and therapeutic taurine treatment on intrauterine ischemia- (IUI-) induced cerebral damage remains unknown. The present work evaluated this issue in male pups subjected to transient IUI (10 min) at E17 and whose mothers received zinc from E1 to E16 and taurine from E17 to postnatal day 15 (PND15) via drinking water. We assessed motor alterations, nitrosative stress, lipid peroxidation, and the antioxidant system comprised of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Enzymes of neuronal energetic pathways, such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH), were also evaluated. The hierarchization score of the protective effect of pharmacological strategies (HSPEPS) was used to select the most effective treatment. Compared with the IUI group, zinc, alone or combined with taurine, improved motor behavior and reduced nitrosative stress by increasing SOD, CAT, and GPx activities and decreasing the GSSG/GSH ratio in the cerebral cortex and hippocampus. Taurine alone increased the AST/ALT, LDH/ALT, and AST/LDH ratios in the cerebral cortex, showing improvement of the neural bioenergetics system. This result suggests that taurine improves pyruvate, lactate, and glutamate metabolism, thus decreasing IUI-caused cerebral damage and relieving motor behavior impairment. Our results showed that taurine alone or in combination with zinc provides neuroprotection in the IUI rat model.

Aberrant methylation and downregulation of ZNF667-AS1 and ZNF667 promote the malignant progression of laryngeal squamous cell carcinoma

Background

Dysregulated long noncoding RNAs (lncRNAs) are involved in the development of tumor. Aberrant methylation is one of the most frequent epigenetic alterations that regulate the expression of genes. The aim of this study was to determine the expression and methylation status of ZNF667-AS1 and ZNF667, elucidate their biological function in the development of LSCC, and identify a cis-regulation of ZNF667-AS1 to ZNF667.

Methods

The expression and methylation status of ZNF667-AS1 and ZNF667 in laryngeal cancer cell lines and LSCC samples were tested respectively. The function of two laryngeal cancer cell lines with overexpression of ZNF667-AS1 or ZNF667 was detected. The regulation between ZNF667-AS1 and ZNF667 was determined.

Results

Significant downregulation of ZNF667-AS1 was detected in laryngeal cancer cell lines and LSCC tumor tissues. The reduced expression of ZNF667-AS1 was associated with moderate/poor pathological differentiation of LSCC tumor tissues. Aberrant hypermethylation of the CpG sites of ZNF667-AS1, closing to the transcriptional start site (TSS), was more critical for gene silencing, and associated with moderate/poor pathological differentiation. In vitro hypermethylation of promoter region closing to TSS of ZNF667-AS1 decreased the luciferase reporter activity. Overexpression of ZNF667-AS1 reduced the proliferation, migration, and invasion ability of AMC-HN-8 and TU177 cells. The sense strand, ZNF667, was positively correlated with ZNF667-AS1 in expression and function. Overexpression of ZNF667-AS1 led to increased expression of ZNF667 in mRNA and protein level. ZNF667-AS1 and ZNF667 may be associated with epithelial-mesenchymal transition (EMT) process.

Conclusions

ZNF667-AS1 and ZNF667 are both down-regulated by hypermethylation, and they serve as tumor suppressor genes in LSCC. ZNF667-AS1 regulates the expression of ZNF667 in cis.

Electronic supplementary material

The online version of this article (10.1186/s12929-019-0506-0) contains supplementary material, which is available to authorized users.

Specific MicroRNAs comparisons in hypoxia and morphine preconditioning against hypoxia-reoxgenation injury with and without heart failure

AIMS

Ischemia reperfusion (I/R) injury is an inevitable event arising during the cardiovascular diseases development and the process of potent surgical treatments. microRNAs (miRNAs) are critical regulators of multiple cell processes including I/R injury. The present study aims to quantify miRNA alterations and regulated genes upon hypoxia-reoxygenation (H/R) injury in a rat heart failure model comparing with normal cardiomyocytes.

MAIN METHODS

Chronic heart failure was established by injecting doxorubicin (2mg/kg/week) for 6weeks, then H/R was performed on primary cultured cardiomyocytes isolated from normal and failed heart. Cellular injury was evaluated by detecting LDH release levels, cell variability and apoptotic rate. Dysregulated miRNAs in control, hypoxia preconditioning (HPC) and morphine preconditioning (MPC) groups under two conditions were quantified by microarray analysis. Fas protein expression was analyzed using Western Blotting analysis.

KEY FINDINGS

Chronic heart failure was confirmed with lower ejection fraction (EF), and significant cellular injury. HPC could reverse the injury induced by H/R in normal heart rather than failed heart, otherwise, MPC significantly attenuated cellular injury dose dependently in both conditions. There was 12 miRNAs significantly altered after doxorubicin injection, 7 downregulated and 5 upregulated. miR-133b-5p, miR-6216, miR-664-1-5p and let7e-5p were differentially expressed after HPC and MPC treatments. The direct interaction between miR-133b-5p and target gene Fas were established. The Fas protein expression was manipulated by MPC not HPC affording protective effect against H/R injury.

SIGNIFICANCE

We investigated that miR-133b-5p might play a particularly important role in the cardioprotective effect of MPC by regulating the target gene Fas.