Acetaminophen, Bupivacaine, Duramorph, and Toradol: A comparison of Gene Expression changes in Osteoarthritic Human Chondrocytes

OBJECTIVES: To determine if exposure to Duramorph results in a lower level of chondrotoxicity than Acetaminophen, Bupivacaine, or Toradol. METHODS: Distal femur and proximal tibia cross sections were obtained during total knee arthroplasty and a 3D Chondrocyte culture technique was performed. Digested cartilage was then treated via an alginate bead culture method to ensure lower rates of differentiation. Chondrocyte cells were exposed to the study chemicals and gene expression and chondrocyte viability were measured by RT-PCR and flow cytometry, respectively. RESULTS: Exposure to Bupivacaine leads to cellular apoptosis with a % PI+ (dead) cells of 30.45, significantly greater than the other test groups P<0.001. Exposure to Toradol, duramorph and acetaminophen did not result in a significant increase in cell death. Bupivicaine also lead to an increase in Caspase 3 gene expression (p<0.001) when compared to all other groups. Acetophinophen also lead to an increased Caspase 3 gene expression when compared to control. Neither Toradol nor Duramorph led to an increase in caspase 3 gene expression. CONCLUSION: Our data show Duramorph and Toradol were not cytotoxic to human chondrocytes and may be better alternatives to the frequently used and more cytotoxic Bupivacaine. Acetominophen did not result in increased cell death however did show increased caspase 3 gene expression and caution should be considered.