Objective To explore the effect and mechanism of uric acid (UA) in regulating the larval growth and development of Drosophila melanogaster. Methods A total of 1350 newly hatched first-instar larvae of wild-type Drosophila melanogaster (W1118) were collected,and the Drosophila melanogaster model of hyperuricemia was constructed with a high purine diet.The larvae were assigned into three groups (n=150):control (standard corn meal medium),low-dose adenine (corn meal medium containing 0.05% adenine),and high-dose adenine (corn meal medium containing 0.10% adenine),and two parallel groups were set up.The growth and development of larvae in each group was observed,and the UA and hormone levels were measured.In addition,the expression levels of genes involved in growth and development were determined. Results Compared with the control group,the low- and high-dose adenine groups showed elevated UA levels (both P<0.001) and prolonged developmental period (P=0.024,P<0.001).The high-dose adenine group showed decreased survival rate,pupation rate,and eclosion rate and elevated levels of juvenile hormone (JH) and 20-hydroxyecdysone (20E) (all P<0.001).The PCR results showed that compared with the control group,high-dose adenine upregulated the mRNA levels of reactive oxygen species (ROS),forkhead box O (FOXO),and mammalian target of rapamycin (mTOR) while downregulating the mRNA levels of Sestrin,mTOR complex 1(mTORC1),and AMP-activated protein kinase (all P<0.001). Conclusion High concentrations of UA may promote the expression of ROS/FOXO/mTORC1/mTOR signaling pathway by regulating the levels of JH and 20E,thereby inhibiting the larval growth and development of Drosophila melanogaster.
目的 探讨尿酸(UA)对果蝇幼虫生长发育的影响及其机制。方法 收集刚孵化的野生型黑腹果蝇(W1118)1龄幼虫1350只,采用高嘌呤饮食构建高尿酸血症果蝇模型,分为对照组(标准玉米粉培养基)、低浓度干预组(含0.05%腺嘌呤的玉米粉培养基)和高浓度干预组(含0.10%腺嘌呤的玉米粉培养基),每组150只,另设2个平行实验组,观察各组幼虫的生长发育情况,测定果蝇体内UA和激素水平,以及生长发育相关基因的表达情况。结果 与对照组比较,低浓度干预组和高浓度干预组果蝇体内UA水平均显著增高(P均<0.001)、果蝇幼虫发育时间显著延长(P=0.024,P<0.001),高浓度干预组果蝇幼虫的生存率、蛹化率、羽化率均显著降低(P均<0.001),而果蝇幼虫体内保幼激素(JH)、20-羟基蜕皮甾酮(20E)水平均显著升高(P均<0.001)。PCR结果显示,与对照组比较,高浓度干预组果蝇幼虫体内活性氧(ROS)、叉头框O亚型(FOXO)、哺乳动物雷帕霉素靶蛋白(mTOR)mRNA的表达水平显著增高,应激诱导蛋白Sestrin、mTOR复合物1(mTORC1)、AMP活化的蛋白激酶mRNA的表达水平显著降低(P均<0.001)。结论 高浓度UA可能通过调节果蝇体内JH、20E的表达,促进ROS/FOXO/mTORC1/mTOR信号通路的表达水平,从而抑制果蝇幼虫的生长发育。.
Keywords: