Hemolysis of human erythrocytes induced by melamine–cyanurate complex

Melamine is a widely-used chemical in industries. In recent years, melamine has been found to be involved in outbreaks of renal injury in infants and animals. Pathological studies indicated that the melamine-induced acute renal failure was related to the concurrence of melamine and other triazine analogs such as cyanuric acid. In the present study, human erythrocytes were used as an in vitro model to explore the cytotoxicity of melamine and its complex with cyanuric acid. The results demonstrated that mixing melamine and cyanuric acid resulted in the formation of insoluble particles and that the insoluble melamine–cyanurate complex induced membrane damages of human erythrocytes. The membrane damages included hemolysis, K+ leakage, alterations in cell shape and membrane fragility, and inhibition of enzymatic activity. By contrast, either melamine or cyanuric acid alone had no effect on erythrocyte membranes. The results of this study may provide a fresh insight into the melamine toxicology.

Research highlights
► Mixing melamine and cyanuric acid resulted in the formation of insoluble complex.
► The insoluble melamine–cyanurate complex is able to cause membrane damage of human erythrocytes.
► Erythrocyte membrane damages included hemolysis, alternations in cell shape and membrane fragility, and inhibition of enzymatic activity.
► The melamine–cyanurate complexes may share same pathway as oxalate crystals to cause cell damage.