Investigation of the Anti-Inflammatory Activity of Fusaproliferin Analogues Guided by Transcriptome Analysis

Abstract

Background: Excessive inflammation results in severe tissue damage as well as serious acute or chronic disorders, and extensive research has focused on finding new anti-inflammatory hit compounds with safety and efficacy profiles from natural products. As promising therapeutic entities for the treatment of inflammation-related diseases, fusaproliferin and its analogs have attracted great interest. However, the underlying anti-inflammatory mechanism is still poorly understood and deserves to be further investigated.Methods: For the estimation of the anti-inflammatory activity of fusaproliferin (1) and its analogs (2-4)in vitro and in vivo, lipopolysaccharide (LPS)-induced RAW264.7 macrophages and zebrafish embryos were employed. Then, transcriptome analysis was applied to guide subsequent western blot analysis of critical proteins in related signaling pathways. Surface plasmon resonance assays (SPR) combined with molecular docking analyses were finally applied to evaluate the affinity interactions between 1-4 and TLR4 and provide a possible interpretation of the downregulation of related signaling pathways.Results: 1-4 significantly attenuated the production of inflammatory messengers, including nitric oxide (NO), reactive oxygen species (ROS), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β), as well as nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), in LPS-induced RAW264.7 macrophages. Transcriptome analyses based on RNA-seq indicated the ability of compound 1 to reverse LPS stimulation and the nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPKs) signaling pathways contribute to the anti-inflammatory process. Experimental verification at the protein level revealed that 1 can inhibit the activation of inhibitor of NF-κB kinase (IKK), degradation of inhibitor of NF-κB (IκB), and phosphorylation of NF-κB and reduce nuclear translocation of NF-κB. 1 also decreased the phosphorylation of MAPKs, including p38, extracellular regulated protein kinases (ERK), and c-Jun N-terminal kinase (JNK). SPR assays and molecular docking results indicated that 1-4 exhibited affinity for the TLR4 protein with KD values of 23.5–29.3 μM.Conclusion: Fusaproliferin and its analogs can be hit compounds for the treatment of inflammation-associated diseases.

N-acetyldopamine dimer inhibits neuroinflammation through the TLR4/NF-κB and NLRP3/Caspase-1 pathways

“…When the organism is invaded by pathogens and endogenous harmful stimuli, the TLR4 receptor will recognize these stimuli and further trigger the activation of downstream NF-κB [29] . Activated NF-κB then translocates into the nucleus and functions as a transcription factor to increase the generation of proinflammatory molecules [ 18 , 30 ] . To investigate whether NADD affects the TLR4/NF-κB pathway, we detected the translocation of NF-κB and the protein levels of TLR4 and NF-κB in BV-2 cells following the administration of NADD.…”

“…In vivo , zebrafish embryos were pretreated with low (15 μM), middle (30 μM) and high (60 μM) concentrations of NADD for 1 h and then co-treated with or without 10 μg/mL LPS for 72 h. During this period, NADD and LPS were refreshed every 24 h. Then, the zebrafish were treated with DCFH-DA for 1 h and anesthetized with tricaine as previous study [18] . Finally, zebrafish were observed under a laser confocal microscope (Olympus, Tokyo, Japan).…”

Anti-Inflammatory Salicin Derivatives from the Barks of Salix tetrasperma

“…Band densities were analyzed by ImageJ software and converted into a graph. 43,44 ■ RESULTS AND DISCUSSION Phytochemical Investigation. The air-dried and powdered barks of S. tetrasperma were soaked with 95% EtOH and then extracted with EtOAc.…”

Complete 1H and 13C assignments of two new sesquiterpenoids from Dendrobium aduncum

“…The absorbance of each cell was measured at 490 nm. [16] Alpha-glucosidase inhibition activity Alpha-glucosidase (560 U/mL) dissolved in a freshly prepared phosphate buffer, then 20 μL of prepared enzyme solution with 100 μL different concentrations (0.4, 2, 10, 50, and 100 μM) of test samples were mixed and incubated at 37 C for 10 min, and then added p-nitrophenylα-D-glycopyranoside (PNPG) substrate (0.01 M) 20 μL and incubated at 37 C for 30 min. Finally, detect its absorbance at a wavelength of 405 nm.…”