The Effect Of The Mixture Of Methyl Paraben And Propyl Ester On The Growth, Reproduction And Type IV Collagen-related Genes Of Female Fruit Flies

Parabens are considered to be a relatively safe preservative and have been widely used in food,medicine,cosmetics and other fields,with methylparaben(MP)and propyl ester(PP)being the most common combination in cosmetics.At present,the research focuses on the estrogen effect of parabens,ignoring the skin is the largest intake of parabens,collagen as the most abundant protein in human tissue,study the effect of parabens on collagen helps to assess the safety of parabens as preservatives.In this study,we used female Drosophila melanogaster(Canton-S strain)as experimental material,MP and PP were mixed at a mass ratio of 1:1(MP+PP),and the parental Drosophila were exposed to different concentration groups and different days from the egg stage.There was no treatment for offspring Drosophila,control group and the low,medium and high MP+PP concentration groups(300 mg·L-1,700 mg L-1,1000 mg·L-1),5 exposure days groups(5 d,10 d,15 d,20 d,25 d)were set,the effects of MP+PP on the developmental cycle and type IV collagen-related genes vkg,Cg25c,mmpl,mmp2 and timp of the parental and offspring female Drosophila were analyzed from the physiological and molecular levels.The results are as follows:(1)The treatment of low concentration group 300 mg·L-1 MP+PP promoted the pupation rate of the parental Drosophila,and the medium concentration group 700 mg·L-1 and the high concentration group 1000 mg·L-1 had a lowering effect.However,compared with the control group,there was no significant difference between them;MP+PP in the middle concentration group and the high concentration group had significant reduction effects on the pupation rate of the offspring Drosophila,but the reduction of low concentration group 300 mg·L-1 was not significant.(2)MP+PP exposure had no significant effect on the emergence rate of Drosophila,but the emergence rate of the middle concentration group and the high concentration group was slightly lower than the control group.The parental Drosophila and the offspring Drosophila showed the same trend,and the different days treatment,there was no significant difference between them.(3)For the parental female Drosophila,the total egg production increased with the increase of treatment concentration,and the total egg production decreased with the increase of treatment time.For the offspring Drosophila,the total egg production was higher than parental Drosophila.There was no significant difference between the low,medium and high concentration groups.There was no significant difference in the number of days of treatment,indicating that the effects on the offspring were much less than the effects on the fertility of the parental female Drosophila.(4)The effects of MP+PP on type IV collagen-related genes,in the parental female Drosophila ovary,the relative expression of vkg and Cg25c decreased with the increase of concentration,but with the increase of treatment days,vkg gene showed relatively higher expression on the 15 d and 25 d;The highest expression level of mmpl,mmp2 gene in the low concentration group 300 mg·L-1 was observed,which was consistent with the highest rate of pupation produced by the parental Drosophila in the low concentration group;Contrast to the parental,the relative expression of vkg and Cg25c in the offspring female Drosophila ovary the amount of both increased,vkg showed that the relative expression of female Drosophila increased on the 5 d and 10 d,and Cg25c showed an increase in overall expression;The relative expression of mmpl and mmp2 was significantly lower in the concentration group than in the control group,this results is consistent with the relative expression of vkg and Cg25c in the ovary of the offspring female Drosophila was higher than that of the parental female Drosophila;The relative expression of timp in the ovary of the parental and offspring Drosophila showed the lowest relative expression in the low concentration group,and the highest relative expression in the medium concentration group,which was the opposite trend of the relative expression of the mmp1 and mmp2 genes,but the relative expression of timp had no obvious regularity between the treatment days,this may due to the multiple regulation of the timp factor.In this study,the effects of MP+PP mixture on the expression of type IV collagen related genes,which is the main component of extracellular matrix of female fruit fly,vkg,Cg25c,mmp1,mmp2 and timp were measured under different concentrations and days.We initially explored the relationship between the effects of MP+PP on Drosophila developmental cycle,fertility and the expression trend of type IV collagen-related genes,the experimental data provide a reference for further study on the toxicological mechanism of parabens.