Urinary Metabonomic Study On HBV-related Liver Failure Patients Treated By ALSS

Liver failure (LF) is an emergency medical condition, manifesteing as jaundice and coagulopathy, complicated by ascites and/or encephalopathy. In Asia-Pacific region, especially China, HBV-related LF patients have an extremely high morbidity and mortality rate due to a high prevalence of chronic HBV infection. Artificial liver support system (ALSS) offers an effective and safe therapeutic option for these patients, either to serve as a valid "bridge" to liver transplantation, the only definitive therapeutic modality for end-stage liver disease, or to give them additional time for native liver recovery, and even remove them from transplant lists. Metabonomics provided a new technical platform for examining ALSS therapy-related changes in metabolites on a global scale. Metabonomics analyze small molecules (<1000 Da) in body fluids or tissues in combination with analytical methodologies and chemometrics. The use of ultra performance liquid chromatography-mass spectrometry (UPLC-MS) in urine analysis provides significant advantages including increased separation speed, increased accuracy of the m/z values, minimized ion suppression and higher resolution.In this paper, urinary metabonomic study in HBV induced LF patients treated by ALSS is based on UPLC/QTOF-MS metabonomic technologies. Metabonomics data processed using MassLynx was further analyzed using Principal Components Analysis (PCA), Partial Least Squares Discriminate (PLS) and Orthogonal Partial Least Squares Discriminate (OPLS). 41 HBV-related LF patients received ALSS therapy in the First Affiliated Hospital, School of Medicine, Zhejiang University were included in this study. Their 3 months outcome after first ALSS treatment was followed up. The diagnosis of HBV-related LF was based on the diagnostic and treatment guidelines for liver failure established in 2008. All patients had a history of hepatitis B and serious debilitation with a total bilirubin (TBiL) of≥171 umol/L or an increase in TBiL by≥17.1 umol/L/day and prothrombin activity (PTA)≤40%.We investigate the urinary metabonomical difference between LF patients and healthy volunteers. Changes induced by ALSS treatment was also studied. Finally, we construct a model to predict the prognosis of HBV related LF patients who received ALSS treatment.The significant decrease in Creatinine, Hippuric acid,2-octenoylcarnitine, a-N-phenylacetyl-L-glutamine(PAGN),2,6-Dimethylheptanoylcarnitine, L-octanoyl-carnitine, and Proline betaine indicate the malfunction of LF patients'liver and renal. The decrease of PAGN after ALSS treatment suggest tha NH3 was lowered in plasma. Creatinine and Glycochenodeoxycholic acid (GCDCA) in dead patients is lower than alive ones illustrates the much poor function of liver and renal. We also found that the fluctuation of GCDCA during the treatment have some relationship with the prognosis.A prognosis model is constructed based on OPLS-O2PLS analysis. The new model's area under the Receiver Operating Characteristic Curve is 0.928, larger than the AUC of the model for end stage liver disease (MELD).Our study based on urinary metabonomic study demonstrates for the first time that ALSS treatment can holistically modify the urine metabolome profiles of LF patients. Moreover, the urine UPLC-MS/MS and the multivariate statistics employed in this study were robust enough for the analysis of complex samples, and our method seems to be a promising technique for assessing the urine metabonomic changes induced by ALSS treatment and for studying the metabolic pathways involved. Further research is required concerning the metabolites identified and their dynamic changes during continual treatment.