Metabonomic Study On The Disease Prediction, Diagnosis And Efficacy Evaluation

The philosophy of Translational Medicine (TM) is to achieve better understanding of human diseases and therefore launch the fundamental studies from which progresses could be efficiently applied to clinical medicinal practice. As to Western Medicine, TM means establishing more sensitive and reliable clinical indicators, while TM in Chinese Traditional Medicine focus on quantitatively and objectively modeling the abstract symptoms. Metabonomics accordingly emerged and has experienced expansive growth. Two frequently used metabonomics approaches are metabolite target analysis and metabolic fingerprinting, with the former stressing the analysis focused on specific metabolites of particular pathways while the later holistically analyzing a group of metabolites to screen potential biomarkers. This dissertation article presented a metabonomics approach in performing TM respectively about the diabetic nephropathy, cerebral infarction and melamine toxicity together with the evaluation of the method's applicability.1. The Study of diabetic nephropathy was based on the quantification of aminothiols. Homocysteine was reported closely related to the chronic renal failure, but its role as an independent factor to the disease still remains controversial. With the goal of exploring the relationship between aminothiols and diabetic nephropathy, the study developed an effective determination method of 8 aminothiols in plasma using HPLC-MS/MS. Aminothiols concentrations of patients were determined according to Mogensen staging and TCM syndrome typing, and the potential biomarkers for the early diagnosis of diabetic nephropathy were identified. The critical diagnose concentration were obtained according to the ROC analysis. Subsequently, the correlation analysis of the quantitative aminothiols, clinical biochemical indictors and TCM symptoms were carried out. It has been shown that S-adenosyl homocysteine was superior to homocysteine in both Mogensen staging and TCM typing, which suggest it could become a better supplemental indicator for the clinical diagnosis of diabetic nephropathy. The quantification method was also applied to the efficacy evaluation of Tangshen Formula, and gratifyingly this TCM intervention showed a positive role in improving the methylation process and oxidative stress in patients.2. The study of cerebral infarction was based on metabolic fingerprinting. Patients with cerebral infarction likely would experience delayed treatment because of lacking rapid and reliable clinical indicators. A determination method of serum metabolic fingerprinting was thus explored and established using UPLC-TOF MS analytical instrumentation with the aid of hierarchical PLS as data processing method. The PLS-DA model between cerebral infarction group and the control group was established and 12 potential biomarkers were located, from which disorder of one-carbon metabolism, fatty acid metabolism and steroid hormone metabolism could be observed relevant to cerebral infarction; then 14 potential biomarkers associated with TCM typing were found between "yin and yang" type. PCA results clearly showed that patients after treatment trended to recover. In addition, PLS-KNN prediction model was unprecedentedly applied to cerebral infarction prediction, and had shown satisfyingly accuracy.3. The study of melamine toxicity was based on metabolic fingerprinting. A large number of infants had miserably suffered from kidney stones, or even death caused by melamine formula scandal. Emergent medications had been administered to relieve the critical situation, but the toxicity mechanism was not clear which prevented more efficient treatment from being used. Metabonomic approach of exploring the melamine toxicity was established. The rat models of different doses of melamine intervention were developed. UPLC-TOF MS was used to obtain plasma and urinary metabolic fingerprinting data. PCA results showed melamine treatment in vivo with a time and dose-dependent characteristics, and PLS-DA model between melamine treatment and normal group pointed out 15 potential plasmic biomarkers and 19 potential urinary biomarkers, suggesting that renal toxicity should be related to the arachidonic acid, purine and pyrimidine, and pentose phosphate metabolism.