Meisoindigo, but not its core chemical structure indirubin, inhibits zebrafish interstitial leukocyte chemotactic migration

Abstract

Context: Inflammatory disease is a big threat to human health. Leukocyte chemotactic migration is required for efficient inflammatory response. Inhibition of leukocyte chemotactic migration to the inflammatory site has been shown to provide therapeutic targets for treating inflammatory diseases.Objective: Our study was designed to discover effective and safe compounds that can inhibit leukocyte chemotactic migration, thus providing possible novel therapeutic strategy for treating inflammatory diseases.Materials and methods: In this study, we used transgenic zebrafish model (Tg:zlyz-EGFP line) to visualize the process of leukocyte chemotactic migration. Then, we used this model to screen the hit compound and evaluate its biological activity on leukocyte chemotactic migration. Furthermore, western blot analysis was performed to evaluate the effect of the hit compound on the AKT or ERK-mediated pathway, which plays an important role in leukocyte chemotactic migration.Results: In this study, using zebrafish-based chemical screening, we identified that the hit compound meisoindigo (25 μM, 50 μM, 75 μM) can significantly inhibit zebrafish leukocyte chemotactic migration in a dose-dependent manner (p = 0.01, p = 0.0006, p < 0.0001). Also, we found that meisoindigo did not affect the process of leukocyte reverse migration (p = 0.43). Furthermore, our results unexpectedly showed that indirubin, the core structure of meisoindigo, had no significant effect on zebrafish leukocyte chemotactic migration (p = 0.6001). Additionally, our results revealed that meisoindigo exerts no effect on the Akt or Erk-mediated signalling pathway.Discussion and conclusion: Our results suggest that meisoindigo, but not indirubin, is effective for inhibiting leukocyte chemotactic migration, thus providing a potential therapeutic agent for treating inflammatory diseases.

Meisoindigo Protects Against Focal Cerebral Ischemia-Reperfusion Injury by Inhibiting NLRP3 Inflammasome Activation and Regulating Microglia/Macrophage Polarization via TLR4/NF-κB Signaling Pathway

“…A recent study indicates that meisoindigo was also found to downregulate the TLR4-TAK-NF-κB pathway, which played critical roles in inflammatory cytokines release (Zhang et al, 2013). In addition, we previously showed that meisoindigo inhibits leukocyte chemotactic migration, which plays a critical role in the inflammatory response (Ye et al, 2017). These observations led us to conjecture that meisoindigo might regulate the immune response via TLR4/NF-κB mediated inflammatory signaling following stroke.…”

“…Meisoindigo is significantly more resistant to protein kinases and exhibits higher antitumor activity than indirubin. Meisoindigo has numerous biological effects, including anti-neoplastic (Cheng et al, 2016), anti-inflammatory (Zhang et al, 2013) and antileukocyte chemotactic effects (Ye et al, 2017). However, whether meisoindigo exerts a neuroprotective action in ischemic stroke remains unknown.…”

Mechanisms of neuronal cell death in ischemic stroke and their therapeutic implications

“…The specific NLRP3 inflammasome inhibitor MCC950 significantly improved neurologic outcomes and reduced infarct volume when administered before or after MCAO 436 . Studies have also shown that meisoindigo, a generally water soluble and well‐tolerated second‐generation indirubin derivative, reduces inflammation by inhibiting leukocyte chemotaxis and migration 437,438 . Meisoindigo posttreatment alleviates brain damage induced by ischemic stroke in vivo and in in vitro model experiments through blocking the activation of the NLRP3 inflammasome 439 .…”

Modeling Inflammation in Zebrafish for the Development of Anti-inflammatory Drugs

“…In addition, structure-function studies have been performed using this model. For example, meisoindigo, which is a derivative of indirubin, a chemical constitute of the traditional Chinese herbal medicine Qing Dai was found to inhibit leukocyte migration induced by tail wounding without affecting reverse migration or Akt and Erk activity, whereas indirubin (which represents the core structure of meisoindigo) did not show an effect (Ye et al, 2017 ). Moreover, a particular chemical group, consisting of fused benzene and pyran rings with an attached carbonyl group (1,4-benzopyrone) or its isomer “coumarin” (1-benzopyran-2-one), was found to be present in four of the nine most-active pro-resolution compounds identified in a large screen of 2,000 well-characterized and approved drugs.…”