Suppression of neutrophil extracellular traps is responsible for the amelioration of chemotherapeutic intestinal injury by the natural compound PEITC.

Intestinal injury is one of the most debilitating side effects of many chemotherapeutic agents, such as irinotecan hydrochloride (CPT-11). Accumulating evidence indicates that neutrophil extracellular traps (NETs) play a critical role in the symptoms of ischemia and inflammation related to chemotherapy. The present study investigated the effects and possible mechanisms of phenethyl isothiocyanate (PEITC) in inhibiting NETs and alleviating chemotherapeutic intestinal injury. CPT-11 induced robust neutrophil activation, as evidenced by increased NETs release, intestinal ischemia, and mRNA expression of inflammatory factors. PEITC prolonged the clotting time of chemotherapeutic mice, improved the intestinal microcirculation, inhibited the expression of inflammatory factors, and protected the tight junctions of the intestinal epithelium. Both in vivo and in vitro experiments revealed that PEITC directly suppresses CPT-11-induced NETs damage to intestinal cells, resulting in significant attenuation of epithelial injury. These results suggest that PEITC may be a novel agent to relieve chemotherapeutic intestinal injury via inhibition of NETs.

Direct Inhibition of GSDMD by PEITC Reduces Hepatocyte Pyroptosis and Alleviates Acute Liver Injury in Mice.

Acute liver injury (ALI), often caused by viruses, alcohol, drugs, etc., is one of the most common clinical liver diseases. Although pyroptosis plays an important role in ALI, there is still a lack of effective clinical drugs related to this mechanism. Here, we show that phenethyl isothiocyanate (PEITC), a natural compound present in cruciferous vegetables, can significantly alleviate concanavalin A (ConA)-induced inflammatory liver damage and carbon tetrachloride (CCl4)-induced chemical liver damage in a dose-dependent manner. PEITC dose-dependently reversed the ALI-induced increase in plasma levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), tumor necrosis factor (TNF)-α, and interferon (IFN)-γ and reduced the protein levels of hepatocyte pyroptosis markers such as Nod-like receptor family pyrin domain containing 3 (NLRP3), cleaved caspase-1, and cleaved gasdermin D (GSDMD). In vitro experiments have also verified the inhibitory effect of PEITC on hepatocyte pyroptosis. Furthermore, PEITC inhibits pyroptosis by interacting with cysteine 191 of GSDMD. In summary, our findings establish a role for PEITC in rescuing hepatocyte pyroptosis via direct inhibition of GSDMD, which may provide a new potential therapeutic strategy for ALI.

Meisoindigo attenuates dextran sulfate sodium-induced experimental colitis via its inhibition of TAK1 in macrophages.

At present, inflammatory bowel disease (IBD) seriously threatens human health, and its treatment is a huge challenge for people. In our studies, we found that meisoindigo, a derivative of indirubin, significantly ameliorated dextran sulfate sodium (DSS)-induced experimental colitis in mice. Meisoindigo treatment markedly elevated the level of glutathione, while suppressed the activities of alkaline phosphatase and myeloperoxidase in colonic tissues. Moreover, the mRNA expression of vascular cell adhesion molecule 1, intercellular adhesion molecule 1, cyclooxygenase-2 which are important colitis-related molecules and the levels of the inflammatory cytokines interleukin (IL)-18, IL-1ß, IL-6, tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS) were suppressed dose-dependently following treatment with meisoindigo. Immunofluorescence results indicated that meisoindigo inhibited macrophage infiltration and nuclear factor (NF)-κB activation in colons from DSS-treated mice. Therefore, mouse RAW264.7 and human THP-1 cells were treated with lipopolysaccharide (LPS) alone or combined adenosine triphosphate to activate NF-κB pathway in vitro. It was shown that meisoindigo reduced the elevated levels of NO, IL-18, IL-1ß and TNF-α after LPS treatment in both cells. In addition, meisoindigo showed inhibitory effects on NF-κB by using a luciferase reporter gene that depends on NF-κB. Through molecular docking, microscale thermophoresis and cellular thermal shift assay. It was further found that meisoindigo targeted transforming growth factor ß activated kinase-1 (TAK1), which is an important regulator in the upstream of NF-κB pathway. In conclusion, our findings show that meisoindigo can alleviate IBD effectively at low doses, and negatively regulate proinflammatory responses by inhibiting the activation of TAK1, which provides new ideas for clinical anti-inflammatory therapy.

Nuclear Factor Erythroid 2 Related Factor 2 Activator JC-5411 Inhibits Atherosclerosis Through Suppression of Inflammation and Regulation of Lipid Metabolism.

Phenethyl isothiocyanate is widely present in cruciferous vegetables with multiple biological effects. Here we reported the antiatherogenic effects and the underlying mechanisms of JC-5411 (Phenethyl isothiocyanate formulation) in vitro and in vivo. Luciferase reporter assay showed that JC-5411 increased the activity of nuclear factor erythroid 2-related factor 2 (Nrf2) and antioxidant response element (ARE). JC-5411 treatment significantly increased the protein expression of Nrf2 and its downstream target gene hemeoxygenase 1 (HO-1) in liver of apolipoprotein E deficient (ApoE-/-) mice. Importantly, JC-5411 treatment significantly reduced atherosclerotic plaque area in both en face aorta and aortic sinus when compared with model group in WD induced ApoE-/- mice. JC-5411 obviously decreased proinflammatory factors' levels in serum of ApoE-/- mice, LPS stimulated macrophages and TNFα induced endothelial cells, respectively. JC-5411 significantly decreased the levels of total cholesterol (TC) and triglyceride (TG) in both serum and liver of ApoE-/- mice and hyperlipidemic golden hamsters. Mechanism studies showed that JC-5411 exerted anti-inflammatory effect through activating Nrf2 signaling and inhibiting NF-κB and NLRP3 inflammasome pathway. JC-5411 exerted regulating lipid metabolism effect through increasing cholesterol transfer proteins (ABCA1 and LDLR) expression, regulating fatty acids synthesis related genes (p-ACC, SCD1 and FAS), and increasing fatty acids ß-oxidation (CPT1A) in vivo. Furthermore, JC-5411 treatment had a favorable antioxidant effect in ApoE-/- mice by increasing the antioxidant related genes expression. Taken together, we conclude that JC-5411 as a Nrf2 activator has anti-inflammatory, rebalancing lipid metabolism, and antioxidant effects, which makes it as a potential therapeutic agent against atherosclerosis.

Surface-enhanced Raman spectroscopy using silver nanoparticles on a precoated microscope slide.

A chemical reduction method was applied to deposit nano silver particles on a frosted microscope slide, precoated with indium tin oxide. The substrate was used to collect the surface-enhanced Raman spectrum of N1'-ethyl indirubin monooxime (EIM), a potential chemical for pharmaceutical application. From the observed surface-enhanced Raman scattering (SERS) spectrum, EIM might interact with silver surface through the lone pair electrons of the oxime nitrogen atoms. Crystal violet (CV) and p-nitrobenzoic acid (PNBA) were also used to test the SERS probe capability of the substrate. The surface morphorlogy of the substrate has been characterized by using scanning electron microscope (SEM) and atomic force microscope (AFM). The elementary composition was identified with Edex and X-ray element scanning.