Apigenin attenuates serum concentrations of TNF-a, interleukin 1b and interleukin 6 in lipopolysaccharide-stimulated rats.

Objective: The use of flavonoids is increasing due to their cost-effectiveness and less adverse reaction. Therefore, the effect of apigenin on lipopolysaccharide (LPS)-induced inflammation was investigated by measuring IL-1b, IL-6, and TNF-a, of serum in the male rats.

Materials and methods: Ninety male wistar rats were divided in 6 groups included; control, sham, dexamethasone 15 mg/kg, intraperitoneally (i.p.), and apigenin (5, 15, and 30 mg/kg, i.p). Thirty minutes after the administration of solvent or apigenin, LPS (30 μg/kg, i.p) was injected. At time intervals of 4, 12 and 24 hr after injection, blood samples were taken and the concentrations of TNF-a, IL-1b and IL-6 were measured by enzyme-linked immunosorbent assay.

Results: Compared to the control, apigenin (5 mg/kg) decreased the level of TNF-a, and IL-1b in a period of 24 hr (p<0.05). The concentration of IL-6 decreased significantly by apigenin (15 mg/kg) 24 hr after injection (p<0.05). Apigenin (30 mg/kg) decreased the level of TNF-a, at all three time points (4 hr; p<0.05, 12 hr; p<0.01, and 24 hr; p<0.01), and the level of IL-1b (p<0.01), 24 hr and the level of IL-6 at 4 hr (p<0.05), and 24 hr (p<0.01) after LPS injection.

Conclusion: Apigenin can suppress serum inflammatory cytokines, similar to dexamethasone.