A Proteomic Approach for the Diagnosis of‘Oketsu’(blood stasis), a Pathophysiologic Concept of Japanese Traditional (Kampo) Medicine

Abstract

‘Oketsu’is a pathophysiologic concept in Japanese traditional (Kampo) medicine, primarily denoting blood stasis/stagnant syndrome. Here we have explored plasma protein biomarkers and/or diagnostic algorithms for‘Oketsu’. Sixteen rheumatoid arthritis (RA) patients were treated withkeishibukuryogan(KBG), a representativeKampomedicine for improving‘Oketsu’. Plasma samples were diagnosed as either having an‘Oketsu’(n= 19) or ‘non-Oketsu’ (n= 29) state according to Terasawa's‘Oketsu’scoring system. Protein profiles were obtained by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) and hierarchical clustering and decision tree analyses were performed. KBG treatment for 4 or 12 weeks decreased the‘Oketsu’scores significantly. SELDI protein profiles gave 266 protein peaks, whose expression was significantly different between the‘Oketsu’and ‘non-Oketsu’ states. Hierarchical clustering gave three major clusters (I, II, III). The majority (68.4%) of‘Oketsu’samples were clustered into one cluster as the principal component of cluster I. The remaining‘Oketsu’profiles constituted a minor component of cluster II and were all derived from patients cured of the‘Oketsu’state at 12 weeks. Construction of the decision tree addressed the possibility of developing a diagnostic algorithm for‘Oketsu’. A reduction in measurement/pre-processing conditions (from 55 to 16) gave a similar outcome in the clustering and decision tree analyses. The present study suggests that the pathophysiologic concept ofKampomedicine‘Oketsu’has a physical basis in terms of the profile of blood proteins. It may be possible to establish a set of objective criteria for diagnosing‘Oketsu’using a combination of proteomic and bioinformatics-based classification methods.