Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, China Pharmaceutical University, Nanjing 210009, People's Republic of China; Institute of Pharmaceutical Research, New Drug Screening Center, China Pharmaceutical University, Nanjing 210009, People's Republic of China.
Key Laboratory of Drug Quality Control and Pharmacovigilance, Ministry of Education, China Pharmaceutical University, Nanjing 210009, People's Republic of China; State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, People's Republic of China; Institute of Pharmaceutical Research, New Drug Screening Center, China Pharmaceutical University, Nanjing 210009, People's Republic of China.
J Pharm Biomed Anal. 2022 Sep 20;219:114979. doi: 10.1016/j.jpba.2022.114979. Epub 2022 Aug 1.
Tryptophan (TRP) metabolism plays a crucial role in pathology and physiology. An imbalance in TRP metabolism has been implicated in the pathology of renal failure. To explore the changes in the TRP profile that occurred in renal failure, we induced experimental models of renal ischemia-reperfusion injury (RIRI) and chronic renal failure (CRF) in rats. A simple, rapid and sensitive method coupling ultra-high-performance liquid chromatography to triple quadrupole mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of TRP and its seven major metabolites in plasma. The method was validated base on linearity, accuracy, precision, stability, recovery and the matrix effect. In the RIRI group, the levels of kynurenine (KYN), 5-hydroxyindoleacetic acid (5-HIAA), tryptamine (Trpm) and kynurenic acid (KA) were increased, and the level of TRP was decreased significantly compared with those of sham group. Moreover, the levels of most of the metabolites measured using the proposed method changed significantly with CRF progression. In the CRF group, the levels of KYN, 5-HIAA, Trpm, KA, 3-hydroxyanthranilic acid (3-HAA) and 3-hydroxykynurenine (3-HK) were dramatically elevated, and the level of TRP was markedly reduced compared with those of the CON group. Plasma precursor metabolite/product metabolite ratios were calculated to characterize enzyme activity. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) of the metabolites were performed for both groups. A Spearman correlation coefficient analysis between the metabolite concentrations and renal injury indicators was performed. We identified KYN, TRP, and 5-HIAA as potential metabolite biomarkers for AKI, and 5-HIAA, TRP, 3-HAA, KA, KYN and 3-HK as potential metabolite biomarkers for CRF (VIP>1 and p < 0.05). These results showed significant changes in the tryptophan metabolism profile under the two types of renal failure. In summary, the results of our study depict the changes in the TRP pathway, reveal the role of the TRP pathway in AKI and CRF, and provide insight into finding potential peripheral biomarkers of renal failure and elucidating the mechanism of diseases related to TRP metabolism disorders.
色氨酸（TRP）代谢在病理生理学中起着至关重要的作用。TRP 代谢失衡与肾衰竭的病理有关。为了探讨肾衰竭时 TRP 谱的变化，我们在大鼠中诱导了肾缺血再灌注损伤（RIRI）和慢性肾衰竭（CRF）的实验模型。建立了一种简单、快速、灵敏的超高效液相色谱-三重四极杆质谱（UPLC-MS/MS）联用方法，同时测定血浆中 TRP 及其七种主要代谢物。该方法基于线性、准确性、精密度、稳定性、回收率和基质效应进行了验证。在 RIRI 组中，与 sham 组相比，犬尿氨酸（KYN）、5-羟吲哚乙酸（5-HIAA）、色胺（Trpm）和犬尿喹啉酸（KA）的水平升高，TRP 的水平显著降低。此外，用所提出的方法测量的大多数代谢物的水平随着 CRF 的进展而显著变化。在 CRF 组中，与 CON 组相比，KYN、5-HIAA、Trpm、KA、3-羟基邻氨基苯甲酸（3-HAA）和 3-羟基犬尿氨酸（3-HK）的水平显著升高，TRP 的水平显著降低。计算血浆前体代谢物/产物代谢物的比值来表征酶活性。对两组代谢物进行主成分分析（PCA）和正交偏最小二乘判别分析（OPLS-DA）。对代谢物浓度与肾损伤指标进行 Spearman 相关系数分析。我们确定 KYN、TRP 和 5-HIAA 是 AKI 的潜在代谢物生物标志物，5-HIAA、TRP、3-HAA、KA、KYN 和 3-HK 是 CRF 的潜在代谢物生物标志物（VIP>1 和 p<0.05）。这些结果表明，在两种类型的肾衰竭下，色氨酸代谢谱发生了显著变化。总之，本研究结果描绘了 TRP 途径的变化，揭示了 TRP 途径在 AKI 和 CRF 中的作用，并为寻找潜在的肾衰竭外周生物标志物和阐明与 TRP 代谢紊乱相关疾病的机制提供了线索。
