Antagonism Effect of Zinc-Metallothionein to Antioxidation-Immune Damage Induced by PM_2.5 in Exercising Rats

Objective To examine the antagonism effect of zinc-metallothionein (Zn-MT) on the antioxidation-immune damage in exercising rats exposed to fine particulate matters (PM_2.5).

Methods Thirty-two male SD rats were randomly assigned into exercise control group,PM_2.5 exposed group,PM_2.5+exercise group,and Zn-MT+PM_2.5+exercise group.All rats were immediately executed after one-time treadmill training with increasing loads and collected lung tissue homogenate samples for measuring oxidative stress indicators including malondialdehyde (MDA),catalase (CAT),glutathione (GSH) and glutathione peroxidase (GSH-Px),and immunity indicators including interleukin-2(IL-2),interleukin-6(IL-6),interleukin-8(IL-8),and monocyte chemoattractant protein-1(MCP-1).

Results The levels of IL-6,IL-8,and MCP-1 increased but the activities of GSH declined in the PM_2.5 exposed group,compared with the exercise control group (P<0.05).The activities of GSH-Px decreased (P<0.01) but the levels of MDA,IL-2,and IL-6 increased in the PM_2.5+exercise group compared with the PM_2.5 exposed group.After adding Zn-MT,compared to the PM_2.5+exercise group,CAT and GSH showed a rising trend but IL-6 and IL-8 declined.

Conclusion Zn-MT could antagonize the antioxidant and immune injury due to PM_2.5 exposure in exercising rats.