甲巯咪唑对甲状腺功能亢进症大鼠尿液代谢组学的影响研究

Effects of methimazole on urinary metabolomics in hyperthyroidism rats

目的研究甲巯咪唑对甲状腺功能亢进症大鼠尿液代谢组学的影响,并初步探讨其可能机制。方法将30只SD大鼠随机分为对照组、模型组、甲巯咪唑组,每组10只。除对照组外其余各组大鼠连续灌胃左甲状腺素钠片(160 mg/kg)15 d复制甲状腺功能亢进症模型,且甲巯咪唑组在造模同时每天灌胃甲巯咪唑(3.6 mg/kg)。观察大鼠基本情况,测量体重和肛温;末次给药后,检测大鼠血清中三碘甲腺原氨酸(T_(3))、四碘甲腺原氨酸(T_(4))、游离三碘甲腺原氨酸(FT_(3))、游离四碘甲腺原氨酸(FT_(4))和促甲状腺激素(TSH)水平。于给药第15天收集各组大鼠24 h尿液,采用超高效液相色谱-飞行时间质谱(UPLC-TOF-MS)技术对大鼠尿液进行代谢组学分析,利用主成分分析和正交偏最小二乘-判别分析筛选差异代谢物,并通过HMDB、KEGG数据库进行代谢通路分析。结果与对照组相比,模型组大鼠肛温和血清中T_(3)、T_(4)、FT_(3)、FT_(4)水平,尿液中差异代谢物癸二酸、利胆酸3-O-葡萄糖醛酸和N6,N6,N6-三甲基-L-赖氨酸表达均显著升高/上调,体重、血清中TSH水平和尿液中脱氧胞苷和2-氧代-4-甲硫基丁酸表达均显著降低/下调(P<0.01)。与模型组相比,甲巯咪唑组大鼠上述指标水平均显著逆转(P<0.05或P<0.01)。上述5个差异代谢物主要涉及戊糖和葡萄糖醛酸相互作用、赖氨酸降解、半胱氨酸和甲硫氨酸代谢以及嘧啶代谢这4条代谢通路。结论甲巯咪唑可能是通过调节戊糖和葡萄糖醛酸相互作用、赖氨酸降解、半胱氨酸和甲硫氨酸代谢以及嘧啶代谢,从而发挥改善甲状腺功能亢进症的作用。

OBJECTIVE To study the effects of methimazole on the urinary metabolomics of hyperthyroidism rats,and to preliminarily investigate its possible mechanism.METHODS Thirty SD rats were randomly divided into control group,model group and methimazole group,with 10 rats in each group.Except for the control group,the rats in the other two groups were given Levothyroxine sodium tablets 160 mg/kg by intragastric administration for 15 days;at the same time,methimazole group was additionally given methimazole 3.6 mg/kg daily by intragastric administration every day.The basic condition of the rats was observed,and the body weight and anal temperature were measured.After the last medication,the serum levels of triiodothyronine(T_(3)),tetraiodothyronine(T_(4)),free triiodothyronine(FT_(3)),free tetraiodothyronine(FT_(4)),and thyroid stimulating hormone(TSH)were determined;24-hour urine was collected on the 15th day after administration.UPLC-TOF-MS was used to analyze the urine metabolomics of rats.Principal component analysis and orthogonal partial least squares-discriminant analysis were used to screen out related differential metabolites,and potential metabolic pathways were analyzed by using HMDB and KEGG.RESULTS Compared with the control group,the rectal temperature,serum levels of T_(3),T_(4),FT_(3) and FT_(4),the expressions of differential metabolites sebacic acid,cholic acid 3-O-glucuronic acid and N6,N6,N6-trimethyl-L-lysine in urine were significantly up-regulated,while body weight,serum level of TSH,the expressions of deoxycytidine and 2-oxo-4-methylthiobutanoic acid in urine were significantly down-regulated(P<0.01).Compared with model group,above indexes of rats were reversed significantly in methimazole group(P<0.01 or P<0.05).Above five differential metabolites were mainly involved in four signaling pathways:pentose and glucuronate interaction,lysine degradation,cysteine and methionine metabolism,and pyrimidine metabolism.CONCLUSIONS Methimazole might improve hyperthyroidism by modulating the four pathways of pentose and glucuronate interaction,lysine degradation,cysteine and methionine metabolism,and pyrimidine metabolism.