Alkaptonuria (AKU) is a rare
genetic disease resulting in severe, rapidly progressing, early onset multi-joint osteoarthropathy. A potential
therapy,
nitisinone, is being trialled that reduces the causative agent;
homogentisic acid (HGA) and in a murine model has shown to prevent
ochronosis. Little is currently known about the effect
nitisinone has on osteoarticular cells; these cells suffer most from the presence of HGA and its polymeric derivatives. This led us to investigate
nitisinone's effect on chondrocytes and osteoblast-like cells in an in vitro model. Human C20/A4 immortalized chondrocytes, and
osteosarcoma cells MG63 cultured in DMEM, as previously described. Confluent cells were then plated into 24-well plates at 4 × 10(4) cells per well in varying concentrations of
nitisinone. Cells were cultured for 7 days with medium changes every third day.
Trypan blue assay was used to determine viability and the effect of
nitisinone concentration on cells. Statistical analysis was performed using analysis of variance, and differences between groups were determined by Newman-Keuls post-test. Analysis of C20/A4 chondrocyte and MG63 osteoblast-like cell viability when cultured in different concentrations of
nitisinone demonstrates that there is no statistically significant difference in cell viability compared to control cultures. There is currently no literature surrounding the use of
nitisinone in human in vitro models, or its effect on chondrocytes or osteoblast like cells. Our results show that
nitisinone does not appear detrimental to cell viability of chondrocytes or osteoblast-like cells, which adds to the evidence that this
therapy could be useful in treating AKU.