Comparative analysis of apoptosis-inducing activity of codeine and codeinone

Area of Science:

• Pharmacology
• Cancer Biology
• Molecular Toxicology

Background:

• Limited research exists on codeine-related compounds' antiproliferative effects on human cancer cell lines.
• Codeinone, an oxidation metabolite of codeine, demonstrated potent cytotoxic and DNA fragmentation activity against HL-60 cells.
• Previous findings indicated that N-acetyl-L-cysteine (NAC) could counteract codeinone's cytotoxic effects.

Purpose of the Study:

• To investigate the apoptosis-inducing effects of codeine and codeinone on human promyelocytic leukemic cell lines (HL-60).
• To elucidate the molecular mechanisms underlying codeinone-induced apoptosis, including mitochondrial pathway involvement.

Main Methods:

• HL-60 cells were treated with codeine or codeinone, followed by assessment of DNA fragmentation using gel electrophoresis and fluorometry.
• Apoptosis was monitored via Hoechst staining, Annexin V staining with FACS, and Western blot analysis for cytochrome c and caspase 3.
• Mitochondrial manganese-containing superoxide dismutase (MnSOD) activity and mRNA expression were analyzed using activity staining and RT-PCR.

Main Results:

• Codeinone induced significantly more internucleosomal DNA fragmentation and Annexin-positive apoptotic cells than codeine in HL-60 cells.
• Codeinone treatment led to the release of cytochrome c and cytochrome oxidase from mitochondria and cleavage of procaspase 3.
• No significant changes were observed in MnSOD activity or expression following codeinone treatment.

Conclusions:

• Codeinone exhibits both apoptosis and necrosis-inducing activities in HL-60 cells.
• These findings, along with its known antinociceptive effects, support codeinone's potential as an antitumor agent.
• Codeinone's mechanism involves the mitochondrial pathway and caspase activation.