Zinc fingers and homeoboxes 1 (ZHX1) is a transcription repressor that has been implicated in the tumorigenesis and progression of diverse tumors. The functional role and regulating mechanism of ZHX1 has not been elucidated in glioblastoma (GBM). Previous reports have suggested that a large number of non-coding RNAs play a vital role in glioma initiation and progression. This study aimed to investigate the functional role and co-regulatory mechanisms of the metastasis-associated lung adenocarcinoma transcript-1 (MALAT1)/ microRNA-199a (miR-199a)/ZHX1 axis in GBM. We analyzed the expression of the MALAT1/miR-199a/ZHX1 axis and its correlation with patients’ overall survival using two different glioma gene-expression datasets. A series of in vitro and in vivo studies including dual luciferase reporter assay, fluorescence in situ hybridization (FISH), RNA immunoprecipitation, and pull-down experiments were completed to elucidate the biological significance of the MALAT1/miR-199a/ZHX1 axis in promoting glioma proliferation and progression. Elevated ZHX1 expression correlated with poor prognosis in GBM patients, and in vitro studies demonstrated that ZHX1 attenuated GBM cell apoptosis by downregulation of pro-apoptotic protein (Bax) and upregulation of anti-apoptotic protein (Bcl-2). Furthermore, knockdown of MALAT1 inhibited GBM proliferation and progression in vitro and reduced tumor volume and prolonged survival in an orthotopic GBM murine model. Finally, we demonstrated that MALAT1 promoted ZHX1 expression via acting as a competing endogenous RNA by sponging miR-199a. The MALAT1/miR-199a/ZHX1 axis promotes GBM cell proliferation and progression in vitro and in vivo, and its expression negatively correlates with GBM patient survival. Blocking the MALAT1/miR-199a/ZHX1 axis can serve as a novel therapeutic strategy for treating GBM.

Elevated expression of lncRNA H19 ( H19 ) in the setting of hypoxia has been implicated as a promising therapeutic target for various cancers. However, little is known about the impact and underlying mechanism of H19 in ischemic brain stroke. This study found that H19 levels were elevated in the serum of stroke patients, as well as in the ischemic penumbra of rats with middle cerebral artery occlusion/reperfusion (MCAO/R) injury and neuronal cells with oxygen glucose deprivation (OGD). Further, knockdown of H19 with siRNA alleviated cell apoptosis in OGD neuronal cells, and inhibition of H19 in MCAO/R rats significantly decreased neurological deficit, brain infarct volume and neuronal apoptosis. Lastly, with gain and loss of function studies, dual luciferase reported assay, RNA immunoprecipitation (RIP) and pull-down experiments, we demonstrated the dual competitive interaction of miR-19a with H19 and the 3’-UTR of Id2 mRNA, resulting in the identification of the H19 -miR-19a-Id2 axis. With biological studies, we also revealed that H19 -miR-19a-Id2 axis modulated hypoxia induced neuronal apoptosis. This study demonstrates that the identified H19 -miR-19a-Id2 axis plays a critical role in hypoxia induced neuronal apoptosis, and blocking this axis may serve as a novel therapeutic strategy for ischemic brain injury.

Background and Purpose: Sirt5 (Sirtuin 5) desuccinylates multiple metabolic enzymes and plays an important role in maintaining energy homeostasis. The goal of this study was to determine whether Sirt5-mediated desuccinylation restores the energy metabolism and protects brain against subarachnoid hemorrhage (SAH). Methods: Male C57BL/6 or Sirt5 −/− mice were used. The endovascular perforation SAH model was applied. Protein lysine succinylation in the brain cortex was examined using liquid chromatography-tandem mass spectrometry analysis. The brain metabolism was evaluated by measurement of brain pH as well as ATP and reactive oxygen species level. Neuronal cell death and neurobehavioral deficits were assessed 24 hours after SAH. The expression and desuccinylation activity of Sirt5, lysine succinylation of citrate synthase and ATP synthase subunits were investigated by Western blot, immunohistochemistry, and ELISA in SAH mice and patients. Furthermore, the benefits of resveratrol-mediated Sirt5 activation were investigated. Results: A total of 211 lysine succinylation sites were differentially expressed on 170 proteins in mice brain after SAH. Thirty-nine percent of these succinylated proteins were localized in mitochondria and they are related to energy metabolism. SAH caused a decrease of Sirt5 expression and succinylated citrate synthase as well as the subunits of ATP synthase, subsequently lowered brain pH, reduced ATP and increased reactive oxygen species production, leading to neuronal cell death, and neurological deficits. Knockdown of Sirt5 aggravated SAH-induced effects, mentioned above. Administration of resveratrol resulted in activation of Sirt5. The activation was accompanied both with restoration of the mitochondrial metabolism and alleviation of early brain injury as well as with desuccinylating citrate synthase and ATP synthase. Conclusions: Protein lysine succinylation is a biochemical hallmark of metabolic crisis after SAH, and disruption of lysine succinylation through activation of Sirt5 might be a promising therapeutic strategy for the treatment of SAH.

Background Bempedoic acid is a new drug that reduces cholesterol synthesis via inhibiting ATP citrate lyase. It remains unclear whether the combination of bempedoic acid and other lipid-lowering drugs is better than these drugs alone. This study systematically reviewed the efficacy and safety of bempedoic acid monotherapy or combination togethers in hypercholesterolemic patients. Methods Randomized controlled trials were searched across Medline, Embase, Cochrane library, web of science, etc. The net change scores [least squares mean (LSM) percentage change] in LDL-C level were meta-analyzed using weighted mean difference. The reductions in other lipids including total cholesterol (TC), non-high-density lipoprotein cholesterol (non-HDL-C) and apolipoprotein (ApoB) and high sensitivity C reactive protein (hsCRP) were also assessed. Odds ratio (OR) of the incidence of adverse events (AEs) were calculated to evaluate the safety of bempedoic acid. Results A total of 13 trials (4858 participates) were included. Pooled data showed that the combination togethers resulted in greater reductions in LDL-C level than monotherapies (bempedoic acid + statin vs. statin: LSM difference (%), − 18.37, 95% CI, − 20.16 to − 16.57, I2 = 0; bempedoic acid + ezetimibe vs. ezetimibe: LSM difference (%), − 18.89, 95% CI, − 29.66 to − 8.13, I2 = 87%). But the difference in efficacy between bempedoic acid and ezetimibe was not obvious. Meta-regression analysis showed the treatment duration was a source of heterogeneity (adj R2 = 16.92, 95% CI, 0.04 to 0.72). Furthermore, the background therapy of statin before screening decreased the efficacy of bempedoic acid. In addition, bempedoic acid also resulted in a significant reduction in TC, non-HDL-C, ApoB and hsCRP level. The OR of muscle-related AEs by the combination of bempedoic acid and statin was 1.29 (95% CI, 1.00 to 1.67, I2 = 0) when compared with statin alone. Conclusion This study showed the efficacy of combination togethers were similar but stronger than these drugs alone. Of note, a trend of high risk of muscle-related AEs by the combination of bempedoic acid and statin was observed, though it is not statistically significant, such risk is needed to be confirmed by more trials, because it is important for us to determine which is the better combinative administration for statin-intolerant patients.