The Increase Of Inflammatory–related Factor MRNA Expression And Liver Damage Induced By Manganese Toxicity In Chicken Livers

Manganese(Mn), is widely distributed in lots of organs and tissues, which as an essential trace element in a variety of different organisms. Mn is very significant in growth and development. However, Mn also as an environmental pollutant. When organism exposure to excessive Mn or prolonged exposure to Mn not only lead to pathological damage, but also produce toxic to the body, such as disturb the nervous, digestive, and genitourinary etc. For now, the domestic and foreign researches about Mn toxicity focus on human, rat and pig, while the reports about poultry were seldom. Therefore, in the study, the healthy of 180 seven-day-old Hyline chicken were were randomly divided into the control group, 600 mg / kg group, 900 mg / kg group and 1800 mg / kg group, each group average divided into 45 chickens. The control group was fed the normal diet, and low-dose group was fed diets with 600 mg / kg Mn, middle-dose group was fed diets with 900 mg / kg Mn, and high-dose group were fed diets with 1800 mg / kg Mn. On 30 d, 60 d and 90 d of this study to kill 15 chickens for sampling liver tissue, and observe microstructure and ultrastructure of liver tissue, measuring the nitric oxide concentration and the activity of inducible nitric oxide synthase. We also examined NF-κB, TNF-α, i NOS, COX-2 and PGE2 m RNA level by RT-PCR. We found that:(1) According to microstructure, ultrastructure, which revealed that Mn could cause the injury in chicken liver.(2) According to the results of kits, we found that NO content and i NOS activity were increased.(3) According to the results of RT-PCR, we found that the NF-κB, TNF-α, i NOS, COX-2, and PGE2 m RNA level were increased.Our results indicated that excess Mn exposure caused the occurrence of inflammatory response, m RNA expression increase of NF-κB, TNF-α, i NOS, COX-2, and PGE2, and the enhancement of NO content and i NOS activity in chicken liver tissue. The results obtained suggest that NF-κB pathway plays an important role in Mn-induced inflammatory response in chicken livers.