To determine the relationship between serum amino acid composition and pathogenesis of ulcerative colitis (UC), so as to explore some new biomarkers for early diagnosis and treatment.

This study was conducted in the 309^th Hospital of Chinese People's Liberation Army between October 2012 and November 2013. Forty-four UC patients and 52 healthy controls were enrolled and the serum samples were collected. Using high performance liquid chromatography-mass spectrometry technology (HPLC-MS/MS) stable isotope internal standard method, we detected serum amino acid metabolic profiling in the two groups.

Compared with the control group, the serum levels of glutamic acid, glutamine, methionine, tryptophan and histidine in UC group were significantly lower [(59.20±21.93) μmol/L vs (88.14±34.85) μmol/L; (2 200.51±648.03) μmol/L vs (2 664.91±1 034.74) μmol/L; (268.69±211.64) μmol/L vs (431.48±298.00) μmol/L; (68.83±32.33) μmol/L vs (89.96±29.29) μmol/L; (101.88±32.01) μmol/L vs (115.10±17.84) μmol/L respectively, all P<0.05]. However, the serum levels of asparagine and isoleucine in UC group were significantly higher than the control group[(195.14±122.14) μmol/L vs (140.49±34.91) μmol/L; (94.61±29.76) μmol/L vs (80.99±19.73) μmol/L respectively; both P<0.05].

The amino acid metabolic profiling in UC patients is different from that in healthy controls, which suggests that there might be a certain relationship between amino acid composition and pathogenesis of UC. Some amino acids would be tested as potential biomarkers in patients with UC.

Colitis, ulcerative; Amino acids; Metabolome; High performance liquid chromatography-mass spectrometry technology; Stable isotope internal standard method