p53-Induced inflammation exacerbates cardiac dysfunction during pressure overload

The rates of death and disability caused by severe heart failure are still unacceptably high. There is evidence that the sterile inflammatory response has a critical role in the progression of cardiac remodeling in the failing heart. The p53 signaling pathway has been implicated in heart failure, but the pathological link between p53 and inflammation in the failing heart is largely unknown. Here we demonstrate a critical role of p53-induced inflammation in heart failure. Expression of p53 was increased in cardiac endothelial cells and bone marrow cells in response to pressure overload, leading to up-regulation of intercellular adhesion molecule-1 (ICAM1) expression by endothelial cells and integrin expression by bone marrow cells. Deletion of p53 from endothelial cells or bone marrow cells significantly reduced ICAM1 or integrin expression, respectively, as well as decreasing cardiac inflammation and ameliorating systolic dysfunction during pressure overload. Conversely, overexpression of p53 in bone marrow cells led to an increase of integrin expression and cardiac inflammation that reduced systolic function. Norepinephrine markedly increased p53 expression in endothelial cells and macrophages. Reducing β₂-adrenergic receptor expression in endothelial cells or bone marrow cells attenuated cardiac inflammation and improved systolic dysfunction during pressure overload. These results suggest that activation of the sympathetic nervous system promotes cardiac inflammation by up-regulating ICAM1 and integrin expression via p53 signaling to exacerbate cardiac dysfunction. Inhibition of p53-induced inflammation may be a novel therapeutic strategy for heart failure.     

Immune Checkpoint Inhibitor Toxicities

Immune checkpoint inhibitors are molecules that increase the endogenous immune response against tumors. They have revolutionized the field of oncology. Since their initial approval for the treatment of advanced melanoma, their use has expanded to the treatment of several other advanced cancers. Unfortunately, immune checkpoint inhibitors have also been associated with the emergence of a new subset of autoimmune-like toxicities, known as immune-related adverse events. These toxicities differ depending on the agent, malignancy, and individual susceptibilities. Although the skin and colon are most commonly involved, any organ may be affected, including the liver, lungs, kidneys, and heart. Most of these toxicities are diagnosed by excluding other secondary infectious or inflammatory causes. Corticosteroids are commonly used for treatment of moderate and severe immune-related adverse events, although additional immunosuppressive therapy may occasionally be required. The occurrence of immune-related toxicities may require discontinuation of immunotherapy, depending on the specific toxicity and its severity. In this article, we provide a focused review to familiarize practicing clinicians with this important topic given that the use of immune checkpoint inhibitors continues to increase.     

Investigation of the mechanisms of Genkwa Flos hepatotoxicity by a cell metabolomics strategy combined with serum pharmacology in HL-7702 liver cells

1. To investigate Genkwa Flos hepatotoxicity, a cell metabolomics strategy combined with serum pharmacology was performed on human HL-7702 liver cells in this study.

2. Firstly, cell viability and biochemical indicators were determined and the cell morphology was observed to confirm the cell injury and develop a cell hepatotoxicity model. Then, with the help of cell metabolomics based on UPLC-MS, the Genkwa Flos group samples were completely separated from the blank group samples in the score plots and seven upregulated as well as two down-regulated putative biomarkers in the loading plot were identified and confirmed. Besides, two signal molecules and four enzymes involved in biosynthesis pathway of lysophosphatidylcholine and the sphingosine kinase/sphingosine-1-phosphate pathway were determined to investigate the relationship between Genkwa Flos hepatotoxicity and these two classic pathways. Finally, the metabolic pathways related to specific biomarkers and two classic metabolic pathways were analyzed to explain the possible mechanism of Genkwa Flos hepatotoxicity.

3. Based on the results, lipid peroxidation and oxidative stress, phospholipase A₂/lysophosphatidylcholine pathway, the disturbance of sphingosine-1-phosphate metabolic profile centered on sphingosine kinase/sphingosine-1-phosphate pathway and fatty acid metabolism might be critical participators in the progression of liver injury induced by Genkwa Flos.