Anti-Inflammatory Activity of β-thymosin Peptide Derived from Pacific Oyster (Crassostrea gigas) on NO and PGE2 Production by Down-Regulating NF-κB in LPS-Induced RAW264.7 Macrophage Cells

Abstract

β-thymosin is known for having 43 amino acids, being water-soluble, having a light molecular weight and ubiquitous polypeptide. The biological activities of β-thymosin are diverse and include the promotion of wound healing, reduction of inflammation, differentiation of T cells and inhibition of apoptosis. Our previous studies showed that oyster β-thymosin originated from the mantle of the Pacific oyster, Crassostrea gigas and had antimicrobial activity. In this study, we investigated the anti-inflammatory effects of oyster β-thymosin in lipopolysaccharide (LPS)-induced RAW264.7 macrophage cells using human β-thymosin as a control. Oyster β-thymosin inhibited the nitric oxide (NO) production as much as human β-thymosin in LPS-induced RAW264.7 cells. It also showed that oyster β-thymosin suppressed the expression of prostaglandin E2 (PGE2), inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, oyster β-thymosin reduced inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6). Oyster β-thymosin also suppressed the nuclear translocation of phosphorylated nuclear factor-κB (NF-κB) and degradation of inhibitory κB (IκB) in LPS-induced RAW264.7 cells. These results suggest that oyster β-thymosin, which is derived from the mantle of the Pacific oyster, has as much anti-inflammatory effects as human β-thymosin. Additionally, oyster β-thymosin suppressed NO production, PGE2 production and inflammatory cytokines expression via NF-κB in LPS-induced RAW264.7 cells.

Berry Phenolic and Volatile Extracts Inhibit Pro-Inflammatory Cytokine Secretion in LPS-Stimulated RAW264.7 Cells through Suppression of NF-κB Signaling Pathway

“…PGE 2 is one of inflammatory mediators produced by COX-2 in inflammatory sites [ 93 ]. Cyclooxygenase is an enzyme involved in prostaglandin synthesis, converting arachidonic acid to prostaglandins [ 94 ]. Isoenzyme COX-1 normally exists to regulate physiological activities in most cells, regardless of stimuli.…”

Kaempferol‑3‑O‑β‑rutinoside suppresses the inflammatory responses in lipopolysaccharide‑stimulated RAW264.7 cells via the NF‑κB and MAPK pathways

“…Cell viability assay. The cytotoxicity of kaempferol-3-Oβ-rutinoside was assayed as reported previously (21). Briefly, cells were treated with kaempferol-3-O-β-rutinoside for 24 h. The medium was replaced with fresh dMEM, and WST-1 solution (daeil Lab Services company, Ltd.) was added for a further 3 h. The absorbance was then measured at 460 nm using a microplate reader (Molecular devices LLc).…”

“…NO assay. To measure the inhibitory activity of kaempferol-3-O-β-rutinoside on NO production, the protocol from a previous study was followed (21). Briefly, the cells were treated with kaempferol-3-O-β-rutinoside for 2 h, and then LPS (1 µg/ml) was added for 18 h. Supernatants were mixed with the same volume of Griess reagent (Sigma-Aldrich; Merck KGaA) and incubated for 15 min.…”

Nardochinoid B Inhibited the Activation of RAW264.7 Macrophages Stimulated by Lipopolysaccharide through Activating the Nrf2/HO-1 Pathway

“…Lipopolysaccharide (LPS), dexamethasone (DEX), and sulforaphane (SFN) were purchased from Sigma Chemical Co. (St. Louis, MO, USA). Antibodies to iNOS [57], COX-2 [58], heme oxygenase (HO)-1 [58], Nrf2 [18], p-p65 [18], p-p38 [18], and phospho-extracellular regulated protein kinases (p-ERK) [18] were obtained from Cell Signaling Technology (Boston, MA, USA). Antibodies to β-actin and laminin B1 [18] were from Santa Cruz Biotechnology (Santa Cruz, CA, USA).…”