Arctigenin protects mice from thioglycollate-induced acute peritonitis

Inflammatory suppression and immunity regulation benefits of honokiol in a rat model of acute peritonitis via the regulation of NLRP3 inflammasome and Sirt1/autophagy axis

BACKGROUND

NLRP3 inflammasome and Sirt1/autophagy axis are potential targets for advancing acute peritonitis (AP). Honokiol (HNK), a bioactive substance, has the potential to improve AP.

MATERIALS AND METHODS

The AP model rats were established by cecal ligation and puncture (CLP). Rats were randomized into the Sham, Sham+HNK, CLP, and CLP+HNK groups. The therapeutic effects of HNK on organ infection, inflammation and immunity were observed in AP rats. The inflammation of RAW 264.7 cells was induced by lipopolysaccharide (LPS) and divided into the Control, HNK, LPS, and LPS+HNK groups. The effects of HNK on immunity and inflammation were observed. Moreover, the inflammatory cell model was further transfected with NLRP3 overexpressing plasmid, and the regulatory effect of HNK on NLRP3 in AP cells was detected.

RESULTS

HNK treatment improved survival, biochemical indexes, and lung and kidney injury and inhibited inflammatory cytokine release and bacterial infection in CLP rats. In CLP rats and RAW 264.7 cells, HNK treatment improved the release of the CD4+ and CD8+ T cells, decreased the associated proteins' levels of the NLRP3 inflammasome, and activated the expression of proteins in the Sirt1/autophagy axis. It improved viability and reduced apoptosis and the degrees of TNF-α, IL-1β, and IL-6 mRNA in RAW 264.7 cells. In addition, HNK treatment antagonized the effect of NLRP3-overexpressed on inflammation and immunity.

CONCLUSIONS

HNK improved AP by inhibiting NLRP3 inflammasome and activating the Sirt1 autophagy axis in vivo and in vitro.

Arctium lappa (Burdock): Insights from ethnopharmacology potential, chemical constituents, clinical studies, pharmacological utility and nanomedicine

Arctium lappa L. is a medicinal edible homologous plant, commonly known as burdock or bardana, which belongs to the Asteraceae family. It is widely distributed throughout Northern Asia, Europe, and North America and has been utilized for hundreds of years. The roots, fruits, seeds, and leaves of A. lappa have been extensively used in traditional Chinese Medicine (TCM). A. lappa has attracted a great deal of attention due to its possession of highly recognized bioactive metabolites with significant therapeutic potential. Numerous pharmacological effects have been demonstrated in vitro and in vivo by A. lappa and its bioactive metabolites, including antimicrobial, anti-obesity, antioxidant, anticancer, anti-inflammatory, anti-diabetic, anti-allergic, antiviral, gastroprotective, hepatoprotective, and neuroprotective activities. Additionally, A. lappa has demonstrated considerable clinical efficacies and valuable applications in nanomedicine. Collectively, this review covers the properties of A. lappa and its bioactive metabolites, ethnopharmacology aspects, pharmacological effects, clinical trials, and applications in the field of nanomedicine. Hence, a significant attention should be paid to clinical trials and industrial applications of this plant with particular emphasis, on drug discovery and nanotechnology.

Intravital Imaging Reveals the Ameliorating Effect of Colchicine in a Photothrombotic Stroke Model via Inhibition of Neutrophil Recruitment

Although post-stroke neutrophil recruitment is known to be deleterious to neural tissues in the peri-infarct area, the precise behavior of recruited neutrophils remains elusive. In this study, potential therapeutic agents for modifying neutrophil behavior in the peri-infarct area were explored through intravital imaging of an experimental stroke mouse model. By applying in vivo 2-photon imaging to study a tightly controlled photothrombotic stroke mouse model, we established a highly sensitive and reproducible method for investigating the temporal dynamics of ischemic brain lesions. Taking advantage of this system, we revealed that neutrophil depletion by a neutrophil-specific antibody ameliorated the expansion of the infarct area, confirming the deleterious effect of neutrophils in the peri-infarct cortex. To identify neutrophil-targeted therapeutic approaches, we screened various agents and found that colchicine and an anti-P-selectin antibody were the most effective in inhibiting neutrophil attachment to the vessel wall in the early phase (6 h post-infarction). Interestingly, further investigation in the later phase (16 h post-infarction) revealed that colchicine potently inhibited neutrophil infiltration into the peri-infarct cortex; however, the anti-P-selectin antibody did not. Subsequent analysis revealed that the effect of the anti-P-selectin antibody against neutrophil attachment to the vessel wall was transient and thus insufficient for mitigating neutrophil infiltration. Finally, we revealed that colchicine treatment effectively ameliorated infarct expansion. In conclusion, we have established an intravital strategy to directly investigate pathophysiology in the ischemic border zone, and found that colchicine administration in the acute phase of ischemic stroke is a potential novel therapeutic strategy.