Cytotoxic Compounds from Wrightia pubescens (R.Br.)

Area of Science:

• Phytochemistry
• Pharmacology
• Cancer Research

Background:

• Phytochemical analysis of Wrightia pubescens (R.Br.) leaves and twigs yielded ursolic acid (1), oleanolic acid (2), squalene (3), chlorophyll a (4), wrightiadione (5), and α-amyrin acetate (6).
• These compounds were isolated from dichloromethane extracts, forming mixtures of ursolic acid and oleanolic acid in 1:1 and 1:2 ratios.

Purpose of the Study:

• To evaluate the cytotoxic potential of isolated compounds (1-6) and their mixtures.
• To assess antiproliferative activities against human cancer cell lines and a normal cell line.

Main Methods:

• Compounds 1-6 and their mixtures were tested for antiproliferative activity.
• The PrestoBlue® cell viability assay was employed.
• Cytotoxicity was evaluated against breast (MCF-7) and colon (HT-29, HCT-116) cancer cell lines, and normal human dermal fibroblast neonatal (HDFn) cells.

Main Results:

• Chlorophyll a (4) demonstrated the highest cytotoxicity against HT-29 cells (IC50 = 0.68 μg/mL), followed by a 1:2 mixture of ursolic acid (1) and oleanolic acid (2) (IC50 = 0.74 μg/mL).
• Oleanolic acid (2) showed significant cytotoxicity against HT-29 (IC50 = 0.89 μg/mL) and HCT-116 (IC50 = 2.33 μg/mL) cells.
• α-Amyrin acetate (6) exhibited the highest cytotoxicity against HCT-116 cells (IC50 = 4.07 μg/mL).
• All tested compounds displayed varying levels of cytotoxicity against HDFn cells (IC50 < 30 μg/mL).

Conclusions:

• The isolated compounds and mixtures from Wrightia pubescens extracts exhibit diverse cytotoxic activities against human cancer cell lines.
• HT-29 cells were most sensitive to the majority of the tested compounds, while HCT-116 cells showed the highest sensitivity to α-amyrin acetate (6).
• The study highlights the potential of these natural compounds in cancer research, with differential activity observed across cell lines, including normal cells.