African Health Sciences
Makerere University Medical School
Vol. 17, No. 1, 2017, pp. 191-198
Bioline Code: hs17024
Full paper language: English
Document type: Research Article
Document available free of charge
African Health Sciences, Vol. 17, No. 1, 2017, pp. 191-198
© Copyright  - African Health Sciences
In vitro investigation of clofazimine analogues for antiplasmodial, cytotoxic and pro-oxidative activities.|
Makgatho, EM & Mbajiorgu, EF
Background: Tetramethyl-piperidine-substituted, B4119 and B4158 have been shown to exhibit antiplasmodial activity.
Objectives: The in vitro antiplasmodial, cytotoxic and oxidative activities of clofazimine and its analogues, all TMP (tetramethylpiperidyl)-
substituted phenazines except B669, were evaluated in this study.
Methods: The antiplasmodial activity of the compounds against RB-1 and pfUP10 laboratory strains of Plasmodium falciparum
was investigated by flow cytometry. The cytotoxic activity against HeLa cells and oxidative activity were studied employing
colorimetric and cytochrome C reduction assays respectively.
Results: The riminophenazine agents exhibited antiplasmodial action of varying degrees: B669, B4100 and B4103 showed
the best activity while B4121 and B4169 exhibited significant activity at 2μg/ml. Clofazimine had no antiplasmodial activity.
The compounds B4100, B4103, B4121 and B4169 exhibited significant cytotoxic activity against HeLa cells at concentrations
of 0.5μg/ml and above while B669 was active at 2μg/ml. Clofazimine and B669 tested at a concentration of 0.5μg/ml caused
enhancement (p ≤ 0.05) of neutrophil superoxide production when compared to the FMLP control while all the other TMP-derivatives
had no effect (p ≥ 0.05).
Conclusion: Tetramethylpiperidyl-subsituted phenazines may potentially be useful antimalarial/antitumor agents with no
pro-oxidative properties. In vivo studies on the agents relative to these properties are recommended.
Riminophenazines; malaria; cytotoxicity and superoxide anions