Systems biochemical responses of rats to Kansui and vinegar-processed Kansui exposure by integrated metabonomics

The dried root of Kansui (Euphorbia kansui L.) is an effective and commonly used traditional Chinese medicine. Even so, Kansui cannot be satisfactorily applied clinically because of toxic side effects. In China, the most common Kansui-processing method uses vinegar to reduce its toxicity. The present study was designed to investigate the toxic effects caused by Kansui and evaluate detoxification of Kansui by vinegar processing of Kansui.

Thirty male Sprague Dawley (SD) rats were randomly assigned to five groups of six rats. Two experimental groups were oral gavaged with 7.875 and 15.75 g Kansui/kg body weight, two treated with 7.875 and 15.75 g VP-Kansui/kg body weight for 14 d, and the control group concurrently subjected to oral gavage with only distilled water. On day 14, plasma, liver and kidney tissues were collected from all rats for biochemistry assessments, histopathological examination, and NMR analyses.

The metabonome of rats treated with Kansui and vinegar-processed (VP-) Kansui was found to differ from that of controls. In liver extracts, the variational metabolites included elevated concentrations of isoleucine, leucine, valine, glutamate, and phenylalanine, with decreased taurine, glucose, and glycogen. However, changes in lysine, methionine, choline, phosphorylcholine, and tyrosine were only observed in Kansui-treated rats. In kidney extracts, prominent changes included elevations in isoleucine, leucine, valine, methionine, creatine/creatinine, and phenylalanine as well as decreased glutamine. Only Kansui treatment induced variations in alanine, lysine, acetate, choline, and phosphorylcholine.

Perturbations in endogenous metabolites induced by Kansui correlated with disturbances in glycolysis and amino acid and lipid metabolism, while biochemical pathway disorders caused by VP-Kansui only involved glycolysis and amino acid metabolism. All results were confirmed by histopathological examination of liver and kidney tissues and clinical biochemistry analyses.