Porphyrin synthesis by human hepatocytes and HepG2 cells--effects of enzyme inducers and delta-aminolevulinic acid.

Experiments were carried out to investigate the possibility of inducing porphyria in human hepatocytes and HepG2 cells in culture. After treatment with hexachlorobenzene, 3-methylcholanthrene, phenobarbital or dimethyl sulfoxide, protoporphyrin was the predominating porphyrin accumulating in presence of delta-aminolevulinic acid. The typical uroporphyrin accumulation, as is seen in hexachlorobenzene-induced porphyria in vivo, was absent. In HepG2 cells, the activities of uroporphyrinogen decarboxylase and porphobilinogen deaminase were not influenced by cytochrome P-450 inducers, hexachlorobenzene or dimethyl sulfoxide during 48 h of culture. Therefore, the use of these cells in the study of porphyria cutanea tarda does not seem promising.