Identification of benzopyrone as a common structural feature in compounds with anti-inflammatory activity in a zebrafish phenotypic screen.

Neutrophils are essential for host defence and are recruited to sites of inflammation in response to tissue injury or infection. For inflammation to resolve, these cells must be cleared efficiently and in a controlled manner, either by apoptosis or reverse migration. If the inflammatory response is not well-regulated, persistent neutrophils can cause damage to host tissues and contribute to the pathogenesis of chronic inflammatory diseases, which respond poorly to current treatments. It is therefore important to develop drug discovery strategies that can identify new therapeutics specifically targeting neutrophils, either by promoting their clearance or by preventing their recruitment. Our recent in vivo chemical genetic screen for accelerators of inflammation resolution identified a subset of compounds sharing a common chemical signature, the bicyclic benzopyrone rings. Here, we further investigate the mechanisms of action of the most active of this chemical series, isopimpinellin, in our zebrafish model of neutrophilic inflammation. We found that this compound targets both the recruitment and resolution phases of the inflammatory response. Neutrophil migration towards a site of injury is reduced by isopimpinellin and this occurs as a result of PI3K inhibition. We also show that isopimpinellin induces neutrophil apoptosis to drive inflammation resolution in vivo using a new zebrafish reporter line detecting in vivo neutrophil caspase-3 activity and allowing quantification of flux through the apoptotic pathway in real time. Finally, our studies reveal that clinically available 'cromones' are structurally related to isopimpinellin and have previously undescribed pro-resolution activity in vivo These findings could have implications for the therapeutic use of benzopyrones in inflammatory disease.

Designing and developing S100P inhibitor 5-methyl cromolyn for pancreatic cancer therapy.

We have previously shown that the antiallergic drug cromolyn blocks S100P interaction with its receptor receptor for advanced glycation end product (RAGE) and improves gemcitabine effectiveness in pancreatic ductal adenocarcinoma (PDAC). However, the concentration required to achieve its effectiveness was high (100 µmol/L). In this study, we designed and synthesized analogs of cromolyn and analyzed their effectiveness compared with the parent molecule. An ELISA was used to confirm the binding of S100P with RAGE and to test the effectiveness of the different analogs. Analog 5-methyl cromolyn (C5OH) blocked S100P binding as well as the increases in NF-κB activity, cell growth, and apoptosis normally caused by S100P. In vivo C5OH systemic delivery reduced NF-κB activity to a greater extent than cromolyn and at 10 times lesser dose (50 mg vs. 5 mg). Treatment of mice-bearing syngeneic PDAC tumors showed that C5OH treatment reduced both tumor growth and metastasis. C5OH treatment of nude mice bearing orthotopic highly aggressive pancreatic Mpanc96 cells increased the overall animal survival. Therefore, the cromolyn analog, C5OH, was found to be more efficient and potent than cromolyn as a therapeutic for PDAC.

Visual compatibility of common nebulizer medications with 7% sodium chloride solution.

PURPOSE: The visual compatibility of hypertonic saline solution with various other drugs used for nebulizer therapy in cystic fibrosis (CF) was assessed. METHODS: Nebulized hypertonic saline solution has proved to be an effective adjunctive therapy for management of CF-related respiratory symptoms. Admixing of hypertonic saline solution and standard medications for nebulizer delivery has been suggested as a way to reduce the time-treatment burden on patients with CF, but that practice has been discouraged due to concerns about potential incompatibilities that could lead to precipitate formation (in the nebulizer or airway) and impeded drug delivery. For the study described here, visual and turbidimetric testing was conducted to assess the compatibility of admixtures of hypertonic saline solution and 11 medications widely used in CF (acetylcysteine, albuterol, atropine, cromolyn sodium, dexamethasone, glycopyrrolate, ipratropium, metaproterenol, sodium bicarbonate, terbutaline, and tobramycin). Three samples each of admixtures of the 11 drugs and 7% sodium chloride (experimental samples) or sterile water for injection (control samples) were prepared. The testing procedure entailed four turbidimetry measurements obtained at 15-minute intervals, as well as visual checks for signs of incompatibility (e.g., haze, particle or gas formation, alteration of color); analysis of variance was used to evaluate differences in test results between the experimental and control samples. RESULTS: Ten of the 11 medications assessed were visually compatible with 7% sodium chloride solution, as determined by serial turbidimetric testing and visual inspection; only cromolyn sodium was found to be visually incompatible with hypertonic saline. CONCLUSION: Eleven medications used in nebulizers for the treatment of CF were visually compatible with 7% sodium chloride solution.