The Influence Of Embryo And Bone Development Exposed By BPA In Rare Minnow Gobiocypris Rarus Offspring

Bisphenol A(BPA)is a kind of important industrial raw material,widely exists in various items in our daily life.The BPA has similar structure with endogenous estrogen(E2)can interfere with the normal endocrine system of the body.In recent years,more and more research suggests that BPA may affect the growth of bone.Collection the various sources of BPA in water that fish living environment.Whether BPA causes fish skeletal development deformity there is no report.Therefore,Gobiocypris rarus(G.rarus)as the research model in this study,research the effects of BPA on the fish skeletal development and molecular mechanism.First female G.rarus exposure to 15,225 ?g/L of BPA 21 d then mating with normal males G.rarus,produce offspring.Then statistical analysis of embryo fertilization rate,mortality rate,hatching rate,deformity rate,heart rate,body length and autonomic movement;Observation of head cartilage development status of G.rarus with cartilage stain;q RT-PCR detection larvae cartilage development related genes expression of bmp 2,bmp 4,bmp 6,sox9 a,runx2,col2?1 and lox1;Detection lysine oxidase(LOX)activity of G.rarus whole fish tissue.The main results were as follows:(1)15 and 225 ?g/L BPAinduced fertilization rate and hatching rate decreased,mortality and malformation rate increased,heart rate significantly accelerate,the ability of autonomic movement weaken,slowed the growth of fish larvae.It suggested that BPA exposed significant inhibition of the G.rarus embryonic developmentand is likely to be produces neurotoxicity.(2).In the treatment group of 225 ?g/L the ceratohyal and mandible was shorten,15 and 225 ?g/L BPA exposure extended the time of cartilage ossification.The results suggest that the G.rarus head cartilage development was significantly suppressed explore to different concentrations of BPA(3)15 and 225 ?g/L BPA exposure,the Sox9 awhich the gene controlling the proliferation of chondroeytes was inhibited,col2?l which is the downstream gene of sox9 a and encodes collagen of cartilage was significantly downregulated.And the expression of bmp 2,bmp 4and bmp 6,Runx2 which regulate chondrocyte hypertrophy was inhibited.BPA may be through inhibiting the cartilage cell proliferation and expands to suppress the formation of cartilage.(4)The activity of the key enzyme controlling the crosslinks between collagen and aggrecan---lysyl oxidase(LOX)were inhibited by BPA.This indicated that the quality of chondrification was affected by BPA,which leaded to the malformations development ofskeletal.In addition,the ontogenesis of G.rarus larvae to 24 days lysine oxidase activity fell sharply,so,24 days is key time point G.rarus individual begins cartilage ossification.Comprehensive above,this study proves that BPA can inhibit skeletal development related gene expressionof bmp s,sox9 a,runx2,col2?1 and lox1,and key enzymes of cartilage formation-LOX activity,thus inhibiting the cartilage formation.,cause G.rarus skeletal deformities.