Cardiolipin oxidized by ROS from complex II acts as a target of gasdermin D to drive mitochondrial pore and heart dysfunction in endotoxemia.

Cardiac dysfunction, an early complication of endotoxemia, is the major cause of death in intensive care units. No specific therapy is available at present for this cardiac dysfunction. Here, we show that the N-terminal gasdermin D (GSDMD-N) initiates mitochondrial apoptotic pore and cardiac dysfunction by directly interacting with cardiolipin oxidized by complex II-generated reactive oxygen species (ROS) during endotoxemia. Caspase-4/11 initiates GSDMD-N pores that are subsequently amplified by the upregulation and activation of NLRP3 inflammation through further generation of ROS. GSDMD-N pores form prior to BAX and VDAC1 apoptotic pores and further incorporate into BAX and VDAC1 oligomers within mitochondria membranes to exacerbate the apoptotic process. Our findings identify oxidized cardiolipin as the definitive target of GSDMD-N in mitochondria of cardiomyocytes during endotoxin-induced myocardial dysfunction (EIMD), and modulation of cardiolipin oxidation could be a therapeutic target early in the disease process to prevent EIMD.

Single NV centers array preparation and static magnetic field detection.

To solve the problem of static magnetic field detection accuracy and consistency, we prepared an array of single NV centers for static magnetic field vector and gradient detection using the femtosecond laser direct writing method. The prepared single NV centers are characterized by fewer impurity defects and good stress uniformity, with an average spatial positioning error of only 0.2 µm. This array of single NV centers can achieve high accuracy magnetic field vector and gradient measurement with GBZ≈-0.047 µT/µm in the Z-axis. This result provides a new idea for large-range, high-precision magnetic field vector and gradient measurements.

Ambient NO2 exposure induced cardiotoxicity associated with gut microbiome dysregulation and glycerophospholipid metabolism disruption.

An average daily increase of 10 µg/m3 in NO2 concentrations could lead to an increased mortality in cardiovascular, cerebrovascular of 1.89%, 2.07%, but the mechanism by which NO2 contributes to cardiotoxicity is rarely reported. In order to assess the cardiotoxicity of NO2 inhalation (5 ppm), we firstly investigate the change of gut microbiota, serum metabonomics and cardiac proteome. Non-targeted LC-MS/MS metabonomics showed that NO2 stress could perturb the glycerophospholipid metabolism in the serum, which might destabilize the bilayer configuration of cardiac lipid membranes. Furthermore, we observed that NO2 inhalation caused augmented intercellular gap and inflammatory infiltration in the heart. Although 16 S rRNA gene amplification sequencing demonstrated that NO2 exposure did not influence the intestinal microbial abundance and diversity, but glycerophospholipid metabolism disruption might be finally reflected in gut microbiom dysregulation, such as Sphingomonas, Koribacter, Actinomarina and Bradyrhizobium Turicibacter, Rothia, Globicatella and Aerococcus. Proteome mining revealed that differentially expressed genes (DEGs) in the heart after NO2 stress were involved in necroptosis, mitophagy and ferroptosis. We further revealed that NO2 increased the number of cardiac mitochondria with depletion of cristae by regulating the expression of Mfn2 and Hsp70. This study indicating Mfn2-meidcated imbalanced mitochondrial dynamics as a potential mechanism after NO2-induced heart injury and suggesting microbiome dysregulation/glycerophospholipid metabolism exerts critical roles in cardiotoxicity caused by NO2.