Propofol Protects Rat Cardiomyocytes from Anthracycline-Induced Apoptosis by Regulating MicroRNA-181a In Vitro and In Vivo

Nrf2: a dark horse in doxorubicin-induced cardiotoxicity

Being a broad-spectrum anticancer drug, doxorubicin is indispensable for clinical treatment. Unexpectedly, its cardiotoxic side effects have proven to be a formidable obstacle. Numerous studies are currently devoted to elucidating the pathological mechanisms underlying doxorubicin-induced cardiotoxicity. Nrf2 has always played a crucial role in oxidative stress, but numerous studies have demonstrated that it also plays a vital part in pathological mechanisms like cell death and inflammation. Numerous studies on the pathological mechanisms associated with doxorubicin-induced cardiotoxicity demonstrate this. Several clinical drugs, natural and synthetic compounds, as well as small molecule RNAs have been demonstrated to prevent doxorubicin-induced cardiotoxicity by activating Nrf2. Consequently, this study emphasizes the introduction of Nrf2, discusses the role of Nrf2 in doxorubicin-induced cardiotoxicity, and concludes with a summary of the therapeutic modalities targeting Nrf2 to ameliorate doxorubicin-induced cardiotoxicity, highlighting the potential value of Nrf2 in doxorubicin-induced cardiotoxicity.

MALAT1 regulates hypertrophy of cardiomyocytes by modulating the miR-181a/HMGB2 pathway

Noncoding RNAs are important for the regulation of cardiac hypertrophy. The function of MALAT1 (a long noncoding mRNA), miR-181a, and HMGB2, their contribution to cardiac hypertrophy, and the regulatory relationship between them during this process remain unknown. In the present study, we treated primary cardiomyocytes with angiotensin II (Ang II) to mimic cardiac hypertrophy. MALAT1 expression was significantly downregulated in Ang II-treated cardiomyocytes compared with control cardiomyocytes. Ang II-induced cardiac hypertrophy was suppressed by overexpression of MALAT1 and promoted by genetic knockdown of MALAT1. A dual-luciferase reporter assay demonstrated that MALAT1 acted as a sponge for miR-181a and inhibited its expression during cardiac hypertrophy. Cardiac hypertrophy was suppressed by overexpression of an miR-181a inhibitor and enhanced by overexpression of an miR-181a mimic. HMGB2 was downregulated during cardiac hypertrophy and was identified as a target of miR-181a by bioinformatics analysis and a dual-luciferase reporter assay. miR-181a overexpression decreased the mRNA and protein levels of HMGB2. Rescue experiments indicated that MALAT1 overexpression reversed the effect of miR-181a on HMGB2 expression. In summary, the results of the present study show that MALAT1 acts as a sponge for miR-181a and thereby regulates expression of HMGB2 and development of cardiac hypertrophy. The novel MALAT1/miR-181a/HMGB2 axis might play a crucial role in cardiac hypertrophy and serve as a new therapeutic target.

Propofol protects cardiomyocytes from doxorubicin-induced toxic injury by activating the nuclear factor erythroid 2-related factor 2/glutathione peroxidase 4 signaling pathways

Propofol offers important protective effects in ischemia/reperfusion-induced cardiomyocyte injury, but its specific mechanisms in doxorubicin (DOX)-induced cardiotoxicity have not been investigated. In this paper, we attempted to explore the effects of propofol on DOX-induced human cardiomyocyte injury and its related mechanisms. H9c2 cell viability was assessed by cell counting kit-8 and lactate dehydrogenase assay kit. Nuclear factor erythroid 2-related factor 2 (NRF2)/glutathione peroxidase 4 (GPx4) signaling pathway-related protein levels were measured by Western blot. Ferroptosis was evaluated by corresponding kits and Western blot and apoptosis was detected by CCK-8, terminal deoxynucleotidyl transferase dUTP nick-end labeling and Western blot. Oxidative stress was assessed by reactive oxygen species kit and the commercial kits, and inflammation response was analyzed by enzyme-linked immunosorbent assay and Western blot. The results showed that propofol attenuated DOX-induced cytotoxicity and activated Nrf2/GPx4 signaling pathways in H9c2 cells. In addition, propofol also alleviated DOX-induced ferroptosis, increased cell viability and inhibited apoptosis, oxidative stress and inflammatory responses in H9c2 cells through activation of Nrf2/GPx4 signaling pathways. In summary, propofol provides the protection against DOX-induced cardiomyocyte injury by activating Nrf2/GPx4 signaling, providing a new approach and theoretical basis for the repair of cardiomyocytes.

Anaesthesia and cancer: can anaesthetic drugs modify gene expression?

Cancer remains a primary cause of morbidity and mortality worldwide, and its incidence continues to increase. The most common cause of death in cancer patients is tumour recurrence. Surgery is the gold standard in the treatment of most tumours. However, cancer surgery can lead to the release of tumour cells into the systemic circulation. Surgical stress and several perioperative factors have been suggested to boost tumour growth, thereby increasing the risk of metastatic recurrence. Preclinical and clinical studies suggest that anaesthetics and adjuvants administered during the perioperative period may impact cancer recurrence and survival. This document summarises the current evidence regarding the effects of anaesthetic drugs and analgesic techniques on the immune system, systemic inflammatory response and tumour cells, as well as their impact on cancer recurrence.

Molecular Mechanisms of Cardiomyocyte Death in Drug-Induced Cardiotoxicity

Homeostatic regulation of cardiomyocytes plays a crucial role in maintaining the normal physiological activity of cardiac tissue. Severe cardiotoxicity results in cardiac diseases including but not limited to arrhythmia, myocardial infarction and myocardial hypertrophy. Drug-induced cardiotoxicity limits or forbids further use of the implicated drugs. Such drugs that are currently available in the clinic include anti-tumor drugs (doxorubicin, cisplatin, trastuzumab, etc.), antidiabetic drugs (rosiglitazone and pioglitazone), and an antiviral drug (zidovudine). This review focused on cardiomyocyte death forms and related mechanisms underlying clinical drug-induced cardiotoxicity, including apoptosis, autophagy, necrosis, necroptosis, pryoptosis, and ferroptosis. The key proteins involved in cardiomyocyte death signaling were discussed and evaluated, aiming to provide a theoretical basis and target for the prevention and treatment of drug-induced cardiotoxicity in the clinical practice.

Propofol inhibited apoptosis of hippocampal neurons in status epilepticus through miR-15a-5p/NR2B/ERK1/2 pathway

Although a previous study reported that propofol had a therapeutic effect in status epilepticus (SE), the mechanisms underlying the effect of propofol in SE remain unclear. The aim of this study was to explore the regulatory mechanisms underlying propofol-induced inhibition of SE.A rat SE model was established using the lithium-pilocarpine injection method. A qRT-PCR and Western blot were utilized to detect the expression of relative molecules. Cell apoptosis was evaluated by a flow cytometry assay. The interaction between miR-15a-5p and NR2B was assessed using a luciferase reporter assay.Propofol inhibited cell apoptosis and increased miR-15a-5p expression both in hippocampal tissues of SE rats and low Mg²⁺-induced hippocampal neurons. Propofol-induced attenuation of apoptosis of low Mg²⁺-induced hippocampal neurons was mediated by miR-15a-5p. miR-15a-5p targeted NR2B and negatively regulated its expression. Propofol downregulated NR2B expression, mediated by miR-15a-5p. In terms of the mechanism of action, propofol suppressed the apoptosis of Mg²⁺-induced hippocampal neurons through the miR-15a-5p/NR2B/ERK1/2 pathway. In vivo experiment suggested that propofol inhibited the apoptosis of hippocampal neurons in SE rats by upregulating miR-15a-5p.In terms of the molecular mechanism of propofol, it appears to inhibit apoptosis of hippocampal neurons in SE through the miR-15a-5p/NR2B/ERK1/2 pathway. The findings provide theoretical support for propofol treatment of SE.

Propofol-mediated cardioprotection dependent of microRNA-451/HMGB1 against myocardial ischemia-reperfusion injury

Administration of propofol at the time of reperfusion has shown to protect the heart from ischemia and reperfusion (I/R) injury. The aim of the present study was to investigate the molecular mechanism underling the cardioprotective effect of propofol against myocardial I/R injury (MIRI) in vivo and in vitro. Rat heart I/R injury was induced by ligation of the left anterior descending (LAD) artery for 30 min followed by 2-hr reperfusion. Propofol pretreatment (0.01 mg/g) was performed 10 min before reperfusion. In vitro MIRI was investigated in cultured cardiomyocytes H9C2 following hypoxia/reoxygenation (H/R) injuries. Propofol pretreatment in vitro was achieved in the medium supplemented with 25 μmol/L propofol before H/R injuries. Propofol pretreatment significantly increased miRNA-451 expression, decreased HMGB1 expression, reduced infarct size, and I/R-induced cardiomyocyte apoptosis in rat hearts undergoing I/R injuries. Knockdown of miRNA-451 48 hr before I/R injury was found to increase HMGB1 expression, infarct size, and I/R-induced cardiomyocyte apoptosis in rat hearts in the presence of propofol pretreatment. These in vivo findings were reproduced in vivo that knockdown of miRNA-451 48 hr before H/R injuries increased HMGB1 expression and H/R-induced apoptosis in cultured H9C2 supplemented with propofol. In addition, luciferase activity assays and gain-of-function studies found that propofol could decrease HMGB1, the target of miRNA-541. Taken together our findings provide a first demonstration that propofol-mediated cardioprotection against MIRI is dependent of microRNA-451/HMGB1. The study provides a novel target to prevent I/R injury during propofol anesthesia.

MicroRNA Expression Profile in Peripheral Blood Lymphocytes of Sheep Vaccinated with Nigeria 75/1 Peste Des Petits Ruminants Virus

Peste des petits ruminants (PPR) is one of the highly contagious transboundary viral diseases of small ruminants. Host microRNA (miRNA) expression patterns may change in response to virus infection, and it mainly works as a post-transcriptional moderator in gene expression and affects viral pathogenesis and replication. In this study, the change of miRNA expression profile in peripheral blood lymphocyte (PBMC) from sheep inoculated with PPR vaccine virus in vivo as well as primary sheep testicular (ST) cells inoculated with PPR vaccine virus in vitro were determined via deep sequencing technology. In PBMC cells, 373 and 115 differentially expressed miRNAs (DEmiRNAs) were identified 3 days and 5 days post inoculated (dpi), respectively. While, 575 DEmiRNAs were identified when comparing miRNA profiles on 5 dpi with 3 dpi. Some of the DEmiRNAs were found to change significantly via time-course during PPR vaccine virus inoculated. Similarly, in ST cells, 136 DEmiRNAs were identified at 3 dpi in comparison with mock-inoculation. A total of 12 DEmiRNAs were validated by real-time quantitative PCR (RT-qPCR). The oar-miR-150, oar-miR-370-3p and oar-miR-411b-3p were found common differentially expressed in both PPR vaccine virus-inoculated PBMC cells and ST cells. Targets prediction and functional analysis of the DEmiRNAs uncovered mainly gathering in antigen processing and presentation pathways, protein processing in endoplasmic reticulum pathways and cell adhesion molecules pathways. Our study supplies information about the DEmiRNAs in PPR vaccine virus-inoculated PBMC cells and ST cells, and provides clues for further understanding the function of miRNAs in PPR vaccine virus replication.

Immune cells as targets for cardioprotection: new players and novel therapeutic opportunities

New therapies are required to reduce myocardial infarct (MI) size and prevent the onset of heart failure in patients presenting with acute myocardial infarction (AMI), one of the leading causes of death and disability globally. In this regard, the immune cell response to AMI, which comprises an initial pro-inflammatory reaction followed by an anti-inflammatory phase, contributes to final MI size and post-AMI remodelling [changes in left ventricular (LV) size and function]. The transition between these two phases is critical in this regard, with a persistent and severe pro-inflammatory reaction leading to adverse LV remodelling and increased propensity for developing heart failure. In this review article, we provide an overview of the immune cells involved in orchestrating the complex and dynamic inflammatory response to AMI-these include neutrophils, monocytes/macrophages, and emerging players such as dendritic cells, lymphocytes, pericardial lymphoid cells, endothelial cells, and cardiac fibroblasts. We discuss potential reasons for past failures of anti-inflammatory cardioprotective therapies, and highlight new treatment targets for modulating the immune cell response to AMI, as a potential therapeutic strategy to improve clinical outcomes in AMI patients. This article is part of a Cardiovascular Research Spotlight Issue entitled 'Cardioprotection Beyond the Cardiomyocyte', and emerged as part of the discussions of the European Union (EU)-CARDIOPROTECTION Cooperation in Science and Technology (COST) Action, CA16225.

Propofol Reduced Mammosphere Formation of Breast Cancer Stem Cells via PD-L1/Nanog In Vitro

Several researches revealed that propofol, a hypnotic intravenous anesthesia agent, could inhibit the cancer cell proliferation and tumor formation, which might affect cancer recurrence or metastasis and impact patients' prognosis. Cancer stem cells (CSCs) comprised a tiny fraction of tumor bulk and played a vital role in cancer recurrence and eventual mortality. This study investigates the effect of propofol on breast cancer stem cells (BCSCs) in vitro and the underlying molecular mechanisms. Tumor formation of CSCs was measured by mammosphere culture. Cultured BCSCs were exposed to different concentrations and durations of propofol. Cell proliferation and self-renewal capacity were determined by MTT assays. Expressions of PD-L1 and Nanog were measured using western blotting and real-time PCR. We knocked down the PD-L1 expression in MDA-MB-231 cells by lentivirus-mediated RNAi technique, and the mammosphere-forming ability of shControl and shPD-L1 under propofol treatment was examined. Mammosphere culture could enrich BCSCs. Compared with control, cells exposed to propofol for 24 h induced a larger number of mammosphere cells (P = 0.0072). Levels of PD-L1 and Nanog were downregulated by propofol. Compared with shControl stem cells, there was no significant difference in the inhibitory effect of propofol on the mammosphere-forming ability of shPD-L1 stem cells which indicated that the inhibition of propofol could disappear in PD-L1 knockdown breast stem cells. Propofol could reduce the mammosphere-forming ability of BCSCs in vitro. Mechanism experiments indicated that the inhibition of propofol in mammosphere formation of BCSCs might be mediated through PD-L1, which was important to maintain Nanog.