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ANTIOXIDANT ACTIVITY OF SELECTED ATYPICAL ANTIPSYCHOTICS

Konstantin Kostić

Center for talented youth Belgrade II, Belgrade, kostic.prof@gmail.com
Supervisor: dr Milan Nikolić, Faculty of Chemistry, University of Belgrade

INTRODUCTION

Atypical antipsychotics are the drugs of choice in the
treatment of schizophrenia. They are antagonists of the
dopamine and serotonin receptors in the brain.
It is believed that oxidative stress (an imbalance between
formation and removal of reactive oxygen species) plays an
important role in the etiology of psychosis, as well as many
other chronic conditions (atherosclerosis,
neurodegenerative diseases, diabetes, etc.). Therefore, the
antioxidant activity of drugs may contribute to their clinical
efficacy, as part of their pleiotropic (unexpected) effects.

OBJECTIVE
The aim of this work was to investigate the antioxidant
activities of selected atypical antipsychotics, using standard Figure 1: Antioxidant activity of selected atypical
in vitro spectrophotometric assays. antipsychotics

MATERIALS AND METHODS As expected, ascorbic acid and Trolox have showed a
marked antioxidant activity (***) in all essays. From the
In this study, the antioxidant activity of the top five most- study drugs, Clozapine showed significant reduction ability
used atypical antipsychotics: Clozapine (Clo), Aripriprazole (**) toward redox-active metals and the detoxification of
(Ari), Quetiapine (Que), Risperidone (Ris) and Olanzapine free radicals. Aripiprazole and Risperidone did not show
(Ola) was evaluated. any antioxidant properties, while Quetiapine and (a little
more) Olanzapine had a mild (*) radical scavenging
The active substances of commercial drug preparations
were isolated by methanol extraction. Trolox® (water activity.
soluble analog of vitamin E) and vitamin C (ascorbic acid)
were used as standard probes. The concentration of the CONCLUSION
tested compounds was 1 mg/mL.
- TEST OF TOTAL REDUCING POWER Atypical antidepressants showed significantly different
3+
This assay is based on the reduction of Fe / ferricyanide antioxidant properties, which may influence the choice of
2+
complex to Fe form, with the formation of Prussian blue. drug from this group for therapeutic purposes. Research
should be extended, by examining possible antioxidant
- TOTAL ANTIOXIDANT CAPACITY activity of these drugs to physiologically important free
radicals (e.g. superoxide anion and hydroxyl radical).
In this test the antioxidant reduces the Mo(VI) to Mo(V),
with the formation of the green phospho/Mo(V) complex.
LITERATURE
- DPPH AND ABTS TEST
Removal of free radicals by the analyzed substances was [1] Stahl's Essential Psychopharmacology: Neuroscientific
estimated following the decolorization of purple DPPH• Basis and Practical Applications, 3rd edition, Cambridge
+
(2,2-diphenyl-1-picrylhydrazyl) and a dark green ABTS• University Press (2008)
(2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)).
[2] Alam MN, Bristi NJ, Rafiquzzaman M. Review on in
vivo and in vitro methods evaluation of antioxidant activity.
RESULTS Saudi Pharm J. 2013; 21(2):143-52.

The results are presented graphically (Figure 1), as the
mean of two independent experiments performed in
duplicate.