C‐phycocyanin protects against ethanol‐induced gastric ulcers in rats: Role of HMGB1/NLRP3/NF‐κB pathway

Abstract

Gastric ulcer is a widespread inflammatory disease with high socio‐economic burden. C‐phycocyanin is one of the active constituents of Spirulina microalgae, and although it is well known for its antioxidant and anti‐inflammatory properties, its protective effects against gastric ulcer have not yet been identified. High‐mobility group box 1 (HMGB1) is a nuclear protein that, once secreted extracellularly, initiates several inflammatory reactions, and it is involved in the pathogenesis of gastric ulcer. The aim of the present study was to investigate the anti‐inflammatory and anti‐ulcerogenic effects of C‐phycocyanin against ethanol‐induced gastric ulcer targeting HMGB1/NLRP3/NF‐κB pathway. Ulcer induction showed increase in HMGB1 expression through activation of nucleotide‐binding domain and leucine‐rich repeat‐containing protein 3 (NLRP3) inflammasome and nuclear factor kappa p65 (NF‐κB p65). Moreover, oxidative stress and inflammatory markers were elevated in the ulcer‐treated group compared to the normal control group. However, pre‐treatment with C‐phycocyanin significantly reduced HMGB1 expression via suppression of NLRP3/NF‐κB, oxidative markers, IL‐1β, tumour necrosis factor‐α (TNF‐α) and ulcer index value. These results were consistent with histopathological and immunohistochemistry examination. Thus, C‐phycocyanin is a potential therapeutic strategy with anti‐inflammatory and anti‐ulcerogenic effects against ethanol‐induced gastric ulcer.

Phycocyanin ameliorates mouse colitisviaphycocyanobilin-dependent antioxidant and anti-inflammatory protection of the intestinal epithelial barrier

“…Phycocyanin has been well documented to exert antiinflammatory effects by inhibiting NF-κB activation in a variety of animal and cellular models of inflammation. [39][40][41] In the present study, PCB showed an equivalent potency to phycocyanin against NF-κB activation and downstream inflammatory responses in human intestine and RAW264.7 cells (Fig. 6, 7b and d), suggesting the critical structural role of PCB in phycocyanin's anti-inflammatory activity.…”

Nutraceutical Strategies for Suppressing NLRP3 Inflammasome Activation: Pertinence to the Management of COVID-19 and Beyond

“…Hence, oral administration of spirulina-or of spirulina extracts enriched in PhyCB-may have clinical potential for suppressing both the priming and activation of inflammasomes. This proposition is supported by recent cell culture and rodent studies [133,134].…”

HMGB1, the Next Predictor of Transcatheter Arterial Chemoembolization for Liver Metastasis of Colorectal Cancer?

“…At present, HMGB1 is known to accelerate angiogenesis by 1) acting on vascular endothelium to promoting the formation of new blood vessels and neovascular network by promoting the synthesis of endothelial growth factor. 2) Acetylated HMGB1, which has been released, activates macrophages to upregulate nuclear factor kappa B, thereby promoting the synthesis and secretion of vascular endothelial growth factor and indirectly promoting the formation of new blood vessels ( 38 , 39 ). 3) HMGB1 can upregulate the expression of fibroblast growth factor (FGF) ( 40 ), stimulate the secretion of platelet-derived growth factor (PDGF) ( 41 , 42 ), and greatly enhance the proliferation and migration ability of endothelial cells.…”