Aristololactam I (AL-I), is the main metabolite of aristolochic acid I (AA-I), participates in the processes that lead to renal damage.Aristololactam I (AL-I) directly injures renal proximal tubule cells, the cytotoxic potency of AL-I is higher than that of AA-I and that the cytotoxic effects of these molecules are mediated through the induction of apoptosis in a caspase-3-dependent pathway[1].
[1]. Li J, et al. Toxicities of aristolochic acid I and aristololactam I in cultured renal epithelial cells. Toxicol In Vitro. 2010 Jun;24(4):1092-7.