A Discovery Of Abnormal Metabolites In Active Lupus Nephritis

Lupus nephritis is one of the most important organ manifestations of Systemic lupus erythematosus(SLE)as well as one of the most important leading causes of death.In clinical practice,the diagnosis of SLE mainly depends on clinical performance and laboratory tests,such as hematuria,proteinuria,tubular urine and 24-hour urine protein quantitation,and renal biopsy remains the gold standard for diagnosis of lupus nephritis.however,it is not always convenient to conduct renal biopsy and complications frequently occur.Moreover,renal biopsy cannot timely reflect the conditions of the renal right now,so physicians are looking forward to other easier ways to diagnose disease and provide guidance for treatments.Metabolomics is a newly emerging study in recent decades,reflecting directly the substance compositions of the tested sample.because it can provide straightforward reflection of human body,it is widely used by scientists to find biomarkers for various disease.In this study we use matrixassisted laser desorption ionization mass spectrometry(MALDI)which has the characteristics of high resolution,high sensitivity and fast detection speed.We also use novel metal materials with high signal-to-noise ratio and no background signals.Serum of 397 healthy controls and 437 SLE patients were tested in this study,and among the SLE patients,210 are without lupus nephritis.We conduct this study to find potential biomarkers for active lupus nephritis.After spectral peak extraction,peak matching,baseline correction,normalization and standardization on the basis of raw data,we use PCA analysis and OPLS-DA analysis to confirm a division between healthy control and SLE group and between disease subtypes.Then through peak difference and MS-MS joint analysis,we discovered 3 abnormal metabolites in active lupus nephritis,which can be potential biomarkers for early diagnosis of disease and provide guidance for treatments.