Effects Of Sesamin On Immune Function In Livers Of Zebrafish(Danio Rerio)Exposed To Fluoride

Sesamin,the main lignan in sesame seeds,has many physiological activities and medicinal properties,but its protective effect on the immune injury of liver exposed to fluoride in zebrafish has not been elucidated.The previous study of this research group found that fluoride exposure can damage the immune system of fish.In order to investigate the effect of sesamin on the immune function of liver exposed to fluoride in zebrafish,this experiment randomly divided healthy zebrafish into 6 groups: blank control group(CK),sesamin group 1(S1),and sesamin group 2(S2),80 mg/L fluoride exposure group(F),80 mg/L fluoride exposure + sesamin group 1(FS1),80 mg/L fluoride exposure + sesamin group 2(FS2).The growth performance of zebrafish was measured at 45 d and 90 d respectively;the histopathological observation of zebrafish liver was performed by HE staining,and the changes of liver antioxidant related indicators(ROS,MDA,SOD and CAT);using enzyme-linked immunosorbent assay to detect changes in liver ACP,AKP and LZM activity;extracting total RNA from zebrafish liver tissue,using real-time fluorescent quantitative PCR method to detect the expression of immune-related genes.The test results are as follows:1.The effects on growth performance showed that after 80 mg/L fluoride exposure for 45 and 90 days,zebrafish body length and weight were decreased,and the growth rate,weight gain rate and specific growth rate were decreased.There was no significant difference in length and weight between the sesamin-treated and fluoride-exposed groups.2.The histopathological results of the liver showed that the liver of the zebrafish exposed to fluoride showed pathological changes,including disordered and broken hepatocytes,vacuole degeneration of the cells,widening of the sinus space,and atrophy of the nucleus.2.0 g/kg sesamin treatment attenuated significantly liver tissue lesions caused by fluoride.The specific manifestations were that the hepatocytes were nearly round and regularly distributed,and the sinus space was narrowed.3.The results of liver antioxidant related tests showed that after exposure to 80 mg/L fluoride for 45 and 90 days,the contents of ROS and MDA were increased,and the activities of SOD and CAT were decreased.Treatment with 1.0 g/kg and 2.0 g/kg sesamin decreased ROS and MDA content,increased SOD and CAT activity.4.The results of liver immune-related enzyme activities showed that exposure to 80 mg/L fluoride for45 and 90 days resulted in a decrease in the activities of ACP,AKP,and LZM.The activities of ACP,AKP,and LZM were significantly reversed after treatment with 1.0 g/kg and 2.0 g/kg sesamin.5.The immune-related genes TNF-α,IFN,IL-11,M17,IL-1β,IL10,IL-6 and IL-12P40 were detected by Real-time quantitative PCR,and the results found that IL-10 m RNA was significantly reduced after 80mg/L fluoride exposure,while the expression levels of other genes were all up-regulated.After sesamin treatment,the expression levels of TNF-α,IFN,IL-11,M17,IL-1β,IL-6 and IL-12P40 m RNAs were decreased,while the expression levels of IL-10 m RNA increased.In summary,sesamin can improve the growth and development of liver by improving the liver immune function by affecting the growth and development of zebrafish,liver tissue structure,immune-related enzymes and related genes exposed to fluoride.Sesamin plays an important role in maintaining zebrafish liver health and preventing fluoride damage to zebrafish liver.