Kalanchoe pinnata (Lam.) Pers. Leaf ethanolic extract exerts selective anticancer activity through ROS-induced apoptotic cell death in human cancer cell lines

• Published in: BMC complementary and alternative medicine Vol. 24; no. 1; pp. 269 - 14
• Main Authors: Faundes-Gandolfo, Nicolas, Jara-Gutiérrez, Carlos, Párraga, Mario, Montenegro, Iván, Vera, Waleska, Escobar, Marcela, Madrid, Alejandro, Valenzuela-Valderrama, Manuel, Villena, Joan
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 15-07-2024; BioMed Central; BMC
• Subjects: Analysis; Anthraquinones; Antineoplastic Agents, Phytogenic - pharmacology; Antioxidant; Antioxidants; Antioxidants - pharmacology; Antitumor activity; Apoptosis; Apoptosis - drug effects; Assaying; Biochemistry; Biocompatibility; Calibration; Cancer; Care and treatment; Caspase; Cell cycle; Cell death; Cell Line, Tumor; Cell proliferation; Cell Proliferation - drug effects; Cells; Chromatin; Chromatography; Colon cancer; Composition; Cytotoxicity; Enzymes; Ergosterol; Esters; Ethanol; Ethanolic extract; Fatty acids; Flavonoids; Fragmentation; Health aspects; Humans; Hydrogen peroxide; In vitro methods and tests; Isoflavones; Kalanchoe - chemistry; Kalanchoe pinnata; Leaves; Liquid chromatography; Medicinal plants; Medicine, Botanic; Medicine, Herbal; Membrane potential; NMR; Nuclear magnetic resonance; Pharmaceuticals; Phenolic compounds; Phenols; Phytochemicals; Phytosterols; Plant Extracts - chemistry; Plant Extracts - pharmacology; Plant Leaves - chemistry; Quercetin; Reactive Oxygen Species - metabolism; Regression analysis; Rhodamine; ROS; Scavenging; Selectivity; Stain; Sterols; Sulforhodamine; Triacontanol; Tropical environment; Tropical environments; Vitamin E; Chile; Asia; Africa; Latin America; Kalanchoe pinnata; Chromatin condensation; Ethanolic extract; ROS; Antioxidant; Apoptosis; Cancer
• ISSN: 2662-7671; 2662-7671; 1472-6882
• DOI: 10.1186/s12906-024-04570-7

The leaves of Kalanchoe pinnata (Lam.) Pers. (K. pinnata), a succulent plant native to tropical regions, are used as a medicinal alternative against cancer in several countries worldwide; however, its therapeutic potential to fight cancer has been little addressed. In this study, we analyzed the phytochemical content, antioxidant capacity, and selectivity of K. pinnata leaf ethanolic extract against different human cancer cell lines in vitro.
This study subjected the ethanolic extract to enzymatic assays to quantify the phytochemical content (phenolics, flavonoids, and anthraquinones) and its radical scavenging and iron-reducing capacities. Also, the phytoconstituents and major phenolic compounds present in the extract's subfractions were identified by GC-MS, HPLC, and NMR. Human cancer (MCF-7, PC-3, HT-29) and normal colon (CoN) cell lines were treated with different concentrations of K. pinnata leaf ethanolic extract, and the changes in cell proliferation (sulforhodamine B assay), caspases activity (FITC-VAD-FMK reporter), mitochondrial membrane potential (MMP, rhodamine 123 assay), chromatin condensation/fragmentation (Hoechst 33342 stain), and ROS generation (DCFH
probe assay) were assessed.
The results showed that the K. pinnata leaf ethanolic extract is rich in phytoconstituents with therapeutic potential, including phenols (quercetin and kaempferol), flavonoids, fatty acid esters (34.6% of the total composition), 1- triacontanol and sterols (ergosterol and stigmasterol, 15.4% of the total composition); however, it presents a poor content of antioxidant molecules (IC
 = 27.6 mg/mL for H
O
scavenging activity vs. 2.86 mg/mL in the case of Trolox). Notably, the extract inhibited cell proliferation and reduced MMP in all human cell lines tested but showed selectivity for HT-29 colon cancer cells compared to CoN normal cells (SI = 8.4). Furthermore, ROS generation, caspase activity, and chromatin condensation/fragmentation were augmented significantly in cancer-derived cell lines, indicating a selective cytotoxic effect.
These findings reveal that the K. pinnata leaf ethanolic extract contains several bioactive molecules with therapeutic potential, capable of displaying selective cytotoxicity in different human cancer cell lines.