The nuclear receptor co-repressor 1 is a novel cardioprotective factor against acute myocardial ischemia-reperfusion injury

Microglia nuclear receptor corepressor 1 deficiency alleviates neuroinflammation in mice

Given the established role of nuclear receptor corepressor 1 (NCoR1) in sensing environmental cues and the importance of inflammation in neurodegenerative diseases, elucidation of NCoR1 involvement in neuroinflammation has notable implications. Yet, its regulatory mechanism remains largely unclear. Under in vitro conditions, NCoR1 expression peaked and then decreased at 12 h after lipopolysaccharides (LPS) stimulation in BV2 cells, However, NCoR1 knockdown using si-RNA attenuated microglial inflammation, evident by reduced the levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX2), phosphorylated-JNK and high mobility group box-1 (HMGB1). Furthermore, NCoR1 suppression could counteract the decline in mitochondrial membrane potential while simultaneously enhancing the expression of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α). Under in vivo conditions, microglia-specific NCoR1 knockout (MNKO) mice after LPS injections alleviated the symptoms of anhedonia, diminished autonomic activity and cognitive impairment. Additionally, MNKO mice showed attenuation of microglial activation, downregulated HMGB1 and COX2, and upregulated PGC-1α expression in the cortex. In conclusion, these findings suggest that NCoR1 deficiency leads to a modest reduction in neuroinflammation, possibly attributed to the increased expression of PGC-1α.

Network pharmacology-based analysis of potential mechanisms of myocardial ischemia-reperfusion injury by total salvianolic acid injection

In this review, we investigated the potential mechanism of Total Salvianolic Acid Injection (TSI) in protecting against myocardial ischemia reperfusion injury (MI/RI). To achieve this, we predicted the component targets of TSI using Pharmmapper and identified the disease targets of MI/RI through GeneCards, DisGenNET, and OMIM databases. We constructed protein-protein interaction networks by analyzing the overlapping targets and performed functional enrichment analyses using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Our analysis yielded 90 targets, which were implicated in the potential therapeutic effects of TSI on MI/RI. Seven critical signaling pathways significantly contributed to TSI's protective effects, namely, PI3K signaling, JAK-STAT signaling, Calcium signaling, HIF-1 signaling, Nuclear receptor signaling, Cell Cycle, and Apoptosis. Subsequently, we conducted a comprehensive literature review of these seven key signaling pathways to gain further insights into their role in the TSI-mediated treatment of MI/RI. By establishing these connections, our study lays a solid foundation for future research endeavours to elucidate the molecular mechanisms through which TSI exerts its beneficial effects on MI/RI.

Insights into the function of HDAC3 and NCoR1/NCoR2 co-repressor complex in metabolic diseases

Histone deacetylase 3 (HDAC3) and nuclear receptor co-repressor (NCoR1/2) are epigenetic regulators that play a key role in gene expression and metabolism. HDAC3 is a class I histone deacetylase that functions as a transcriptional co-repressor, modulating gene expression by removing acetyl groups from histones and non-histone proteins. NCoR1, on the other hand, is a transcriptional co-repressor that interacts with nuclear hormone receptors, including peroxisome proliferator-activated receptor gamma (PPARγ) and liver X receptor (LXR), to regulate metabolic gene expression. Recent research has revealed a functional link between HDAC3 and NCoR1 in the regulation of metabolic gene expression. Genetic deletion of HDAC3 in mouse models has been shown to improve glucose intolerance and insulin sensitivity in the liver, skeletal muscle, and adipose tissue. Similarly, genetic deletion of NCoR1 has improved insulin resistance and reduced adiposity in mouse models. Dysregulation of this interaction has been associated with the development of cardio-metabolic diseases such as cardiovascular diseases, obesity and type 2 diabetes, suggesting that targeting this pathway may hold promise for the development of novel therapeutic interventions. In this review, we summarize the current understanding of individual functions of HDAC3 and NCoR1/2 and the co-repressor complex formation (HDAC3/NCoR1/2) in different metabolic tissues. Further studies are needed to thoroughly understand the mechanisms through which HDAC3, and NCoR1/2 govern metabolic processes and the implications for treating metabolic diseases.

In vivo and in vitro impact of atorvastatin against myocardial ischaemia-reperfusion injury by upregulation of silent information regulator l and attenuation of endoplasmic reticulum stress-induced apoptosis

We aimed to investigate the effects and mechanism of Atorvastatin on Myocardial Ischaemia-Reperfusion Injury in vitro and in vivo. The effects of Atorvastatin on Silent information regulator l (SIRT1) and endoplasmic reticulum (ER) stress were investigated in Myocardial ischaemia-reperfusion (MI/R) injury rat model and hypoxia/reoxygenation (H/R)-treated H9c2 cells. Pathological changes, inflammatory and heart injury markers, cell apoptosis and cell death, SIRT1 and cleaved Caspase-12 expressions, and ER stress relative proteins were measured through HE, enzyme-linked immunosorbent assay, quantitative TUNEL and flow cytometry, immunofluorescence and Western blotting with the assistance of the SIRT1 specific inhibitor EX527 and ER stress pathway blocker treatment. The results of our study demonstrated that atorvastatin treatment attenuated MI/R and H/R mediated inflammatory and heart injury markers, cell apoptosis and cell death, SIRT1 and cleaved Caspase-12 expressions, and ER stress relative protein levels. Finally, we found that atorvastatin reversed SIRT1 expression and blockade the ER stress pathway and increase the cardiomyocytes survival rate in the presence of MI/R and H/R. Our findings provided a new rationale for subsequent academic and clinical research on MI/R injury.

PPARγ Mediates the Cardioprotective Roles of Danlou Tablet After Acute Myocardial Ischemia-Reperfusion Injury

Ischemic heart disease is one of the biggest threats to human life in the world. Reperfusion therapy is an effective strategy to reduce infarct size and ischemic injury. However, reperfusion process may cause secondary myocardial injury which is defined as ischemia-reperfusion injury (IRI). Exploring potential therapeutic strategy to attenuate IRI is extremely important. Danlou tablet (Dan), a Chinese herbal compound consisting of ten herbs, has been identified to be protective for the heart. However, the mechanism of Dan-induced cardioprotection after acute reperfusion was unelucidated. In this study, to investigate the role and mechanism of Dan in myocardial IRI, we performed acute IRI modeling in mice and oxygen-glucose deprivation–reperfusion (OGD/R)-induced apoptosis in primary neonatal rat cardiomyocytes (NRCMs). We found that Dan had protective effect against acute IRI in mice, as evidenced by reduced infarct size, TUNEL-positive cardiomyocytes (CMs), and Bax/Bcl2 ratio and cleaved-caspase 3/caspase 3 ratio in vivo. Meanwhile, Dan inhibited OGD/R-induced apoptosis of NRCMs in vitro. Mechanistically, Dan could activate proliferator-activated receptor gamma (PPARγ) in both IRI hearts and OGD/R-stressed NRCMs, while inhibition of PPARγ attenuated the protective effect of Dan against IRI in vivo and OGD/R-induced CM apoptosis in vitro. These data reveal that Dan attenuates acute myocardial IRI and CM apoptosis through activating PPARγ. Our findings may extend the knowledge of Chinese medicine and provide potential strategy for the precise treatment of ischemic heart diseases.