Comparative in vitro Evaluation of the Antioxidant Potential of Apomorphine and Pyrazolones for Hepatocellular Carcinoma

Background

Hepatocellular Carcinoma (HCC) is a common and highly aggressive form of cancer worldwide. Oxidative stress is closely associated with the development and progression of HCC. An excessive increase in Reactive Oxygen Species (ROS) may damage important cellular components, including DNA, lipids, and proteins, through processes such as DNA damage, lipid peroxidation, protein oxidation and dysregulation of cellular signalling pathways. Therefore, compounds possessing antioxidant properties may help mitigate oxidative damage and provide therapeutic benefits in HCC.

Objectives

This study was undertaken to assess the antioxidant activity of Apomorphine and Pyrazolones using multiple in vitro antioxidant assays in HepG2 cells.

Materials and Methods

Antioxidant activity was determined through a series of in vitro assays, including DPPH radical scavenging, Ferric Reducing Antioxidant Power, Thiobarbituric Acid Reactive Substances, Nitric Oxide scavenging and Hydrogen Peroxide (H₂O₂) scavenging assays. HepG2 cells were cultured under standard laboratory conditions and treated with the test compounds. Antioxidant activity was expressed as IC₅₀ values where applicable, Lipid peroxidation was assessed by determining the levels of Malondialdehyde (MDA). The obtained data were statistically investigated using GraphPad Prism software and presented as mean±standard deviation.

Results

Apomorphine and Pyrazolones exhibited measurable antioxidant activity in multiple assays. In the DPPH assay, Apomorphine demonstrated greater radical scavenging activity (IC₅₀=66.90±0.028 µg/mL) than Pyrazolones (IC₅₀=97.26±0.031 µg/mL). In the FRAP assay, both compounds showed ferric reducing activity with IC₅₀ values of 4.822±0.247 µg/mL and 4.127±0.832 µg/mL, respectively. TBARS analysis revealed lower MDA levels in the Apomorphine-treated group (4.615 nmoles/mL) compared with the Pyrazolones-treated group (6.795 nmoles/mL), indicating reduced lipid peroxidation. Both compounds also exhibited nitric oxide scavenging activity. However, the IC₅₀ values obtained for both compounds in the hydrogen peroxide scavenging assay exceeded the highest concentration tested.

Conclusion

The findings indicate that Apomorphine and Pyrazolones possess significant antioxidant properties with Apomorphine demonstrating comparatively stronger antioxidant activity in several evaluated parameters. These results suggest that both compounds may contribute to the regulation of oxidative stress and warrant further investigation to elucidate their potential biological significance in hepatocellular carcinoma.