Antioxidant, Cytotoxic and Apoptotic Properties of Aqueous Extracts of Fleurya Aestuans and Momordica Charantia on Prostate Cancer Cell Lines

Abstract

Background: Prostate cancer is the second highest cancer type among men in Africa. It brings financial and healthcare burden to a number of patients in Ghana. It accounted for about 30% of all cancers recorded in males in the year 2000 at the Korle-Bu Teaching Hospital, Accra - Ghana. Thus, there is a need for other therapeutic agents (interventions) Momordica chrantia (MCwp) and Fleurya aestuans (FAwp) plants are known to possess anticancer, anti-diabetic and anti-inflammatory properties. However, there is a dearth of information on the efficacy of both plants in the management of prostate cancer. Aim: This study aimed at determining direct cytotoxic, anti-oxidant and pro-apoptotic activities of aqueous extracts of the leaves of MCwp and FAwp on PC3 and LNCaP prostate cancer cell lines. Methodology: Aqueous extracts of the leaves of MCwp and FAwp were prepared from pulverized samples, with 11% and 14.96% yields, respectively. PC3 and LNCaP prostate cell lines were cultured in RPMI media substituted with 10% FBS and 1% penicillin-streptomycin. Morphological cellular changes were observed at 3, 6 and 24 h post-treatment with extracts and control compounds (ursolic acid and curcumin) using a Phase Contrast light microscope at 20X magnification. Cytotoxic activities of increasing concentrations of the extracts were ascertained using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on the two prostate cancer cell lines, PC3 and LNCaP. The pro-apoptotic activity of the extracts were assessed using the DNA laddering assay. The JC-1 mitochondrial assay was also used to assess the intof rinsic pro-apoptotic pathway. The antioxidant properties of the extracts were evaluated using 2, 2 diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power assay. Total phenolic content of the extracts were determined by Folin-Ciocalteu reagent method. Results: Morphological changes of cells post-treatment: Ursolic acid (UA) and curcumin (positive controls caused apoptosis with ursolic acid showing more apoptotic cells in both cell lines at 24h post treatment.. FAwp and MCwp apoptotic activity was highest at 6 h post treatment MTT Assay: FAwp was more cytotoxic to PC3 cells compared to MCwp. Curcumin had the least IC50 value of 2.10 μg/ml, and UA had IC50 value of 9.90 μg/ml. FAwp showed a concentration-dependent reduction in percentage mean cell viability with an IC50 value of 20.39 μg/ml, while that of MCwp was 38.22 μg/ml. The IC50 values for curcumin and ursolic acid in LNCaP-treated cells, with a value of 7.611 μg/ml and 34.44 μg/ml, respectively, whilst that of MCwp was 75.75 μg/ml. FAwp exhibited least cytotoxic against LNCaP (>100 μg/ml). Mitochondrial membrane potential assay: MCwp had the least JC-1 monomer at 24 h for both PC3 and LNCaP. FAwp exhibited highest pro-apoptotic activity at 24 h post-treatment on PC3. DNA fragmentation: Apoptotic bodies were formed in both cells treated with FAwp and MCwp. Antioxidant capacity (DPPH Assay): FAwp and MCwp had an EC50 values > 5 mg/ml. Total phenolics/Gallic acid assay: The Total phenolic content of FAwp was 1.97 mg/100g GAE. Whiles that of MCwp was 3.622 mg/100g GAE. Conclusion: Both FAwp and MCwp had direct cytotoxic activities on PC3 and LNCaP prostate cell lines. They had anti-oxidant and apoptotic activity.