DL-Tryptophan is a racemic mixture of the atypical amino acid D-tryptophan and the essential amino acid L-tryptophan .1,2 Serum levels of DL-tryptophan are negatively correlated with urinary protein levels in a rat model of nephropathy induced by doxorubicin .3
1.Grishin, D.V., Zhdanov, D.D., Pokrovskaya, M.V., et al.D-amino acids in nature, agriculture and biomedicineAll Life13(1)11-22(2020) 2.Richard, D.M., Dawes, M.A., Mathias, C.W., et al.L-Tryptophan: Basic metabolic functions, behavioral research and therapeutic indicationInt. J. Tryptophan Res.245-60(2009) 3.Li, A.-P., Yang, L., Zhang, L.-C., et al.Evaluation of injury degree of adriamycin-induced nephropathy in rats based on serum metabolomics combined with proline markerJ. Proteome Res.19(7)2575-2584(2020)