Abstract:Aim To investigate whether acylated ghrelin can protect 3T3-L1 mouse adipocytes from inflammatory injury mediated by inflammatoral factor tumour-necrosis factor-α (TNF-α). Methods Four experimental groups were set up: control group, TNF-α treated group, acylated ghrelin treated group and a group pretreated by acylated ghrelin followed by TNF-α treatment. After the completion of the intervention, the mRNA and protein levels of Toll-like recepter 4 (TLR-4), nuclear factor κB p65 (NF-κB p65) protein phosphorylation level, the concentration of monocyte chemotactic protein 1 (MCP-1) and adiponectin in the supernatant were detected. Results ① Compared with control group, mRNA and protein expression level of TLR-4 were increased by TNF-α intervention, as well as level of NF-κB p65 protein phosphorylation and MCP-1 protein in the murine 3T3-L1 adipocytes (P<0.05,n5). On the contrary, the adiponectin protein was decreased(P<0.05,n5). ②Compared with control group, the level of TLR-4 mRNA and protein expression, as well as NF-κB p65 protein phosphorylation were significantly decreased in acylated ghrelin treated group (P<0.05,n5). The adiponectin level in the cell supernatant was decreased (at 15 pmol/L most obvious) (P<0.05,n5 ), while level of the MCP-1 went down without statistically significant difference (P>0.05,n5). ③Compared with TNF-α(100 μg/L) treated group, the incubation of acylated ghrelin could antagonise TNF-α-induced activation of TLR-4/NF-κB pathway in mouse 3T3-L1 adipocytes, mRNA and protein expression levels of TLR-4, the level of NF-κB p65 protein phosphorylation were decreased (P<0.05,n5) in a dose-dependent manner. The secretion of MCP-1 and adiponectin did not change significantly in 3T3-L1 adipocytes (P>0.05,n5). Conclusions TNF-α can activate TLR-4/NF-κB inflammatory pathways and increase secretion of pro-inflammatory cytokines (MCP-1), while decrease the secretion of anti-inflammatory cytokines (adiponectin) in 3T3-L1 adipocytes. Acylated ghrelin can antagonise TNF-α-induced activation of TLR-4/NF-κB pathway in a dose-dependent manner in mouse 3T3-L1 adipocytes, but can not completely improve the secretion disorder of MCP-1 and adiponectin.