Black cardamom (Amomum subulatum Roxb.) fruit extracts exhibit apoptotic activity against lung cancer cells

Pooja Makhija; Harish K Handral; Gomathi Mahadevan; Himanshu Kathuria; Gautam Sethi; Bert Grobben

doi:10.1016/j.jep.2021.114953

Black cardamom (Amomum subulatum Roxb.) fruit extracts exhibit apoptotic activity against lung cancer cells

J Ethnopharmacol. 2022 Apr 6:287:114953. doi: 10.1016/j.jep.2021.114953. Epub 2021 Dec 27.

Authors

Pooja Makhija¹, Harish K Handral², Gomathi Mahadevan³, Himanshu Kathuria⁴, Gautam Sethi⁵, Bert Grobben⁶

Affiliations

¹ Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore. Electronic address: pooja@u.nus.edu.
² Stem Cell Bioprocessing Technology Institute (BTI), Agency for Science, Technology, and Research (A*STAR), 20 Biopolis Way, 138668, Singapore.
³ Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore.
⁴ Department of Pharmacy, National University of Singapore, 117543, Singapore; Nusmetics Pte Ltd, Makerspace, i4 building, 3 Research Link, 117602, Singapore. Electronic address: himanshukathuria01@u.nus.edu.
⁵ Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Blk MD3, 16 Medical Drive, 117600, Singapore.
⁶ Budding Innovations Pte Ltd, 06-02 80 Jellicoe Rd, 208766, Singapore. Electronic address: bert.grobben@budinno.com.

PMID: 34968666
DOI: 10.1016/j.jep.2021.114953

Abstract

Ethnopharmacological relevance: The dried fruits of Amomum subulatum Roxb. (A. subulatum) are widely used as a spice. It is a part of official ayurvedic formulations used in folklore medicine to treat cancer.A. subulatum has been used in ayurvedic formulations to treat various lung conditions such as cough, lung congestion, pulmonary tuberculosis. The present traditional knowledge highlights the effectiveness of A. subulatum in treating cancer and its lung-specific efficacy.

Aim of the study: This study aims to investigate the cytotoxic potential of A. subulatum on the phenomenal and mechanistic level of lung cancer cells and identify the presence of A. subulatum actives.

Materials and methods: The bioactivity of the extracts was tested using MTT assay, apoptotic assay, cell cycle analysis, superoxide production assay, reactive oxygen species (ROS) assay, and western blot analysis. Firstly, five different extracts were prepared using sequential extraction, and then screening of cell lines was performed using MTT assay.

Results: Lung cancer cells were selected as the most sensitive target, and dichloromethane extract (DE) was the most active extract. Annexin assay confirmed the mode of cell death as apoptosis. SubG₁ peak found in cell cycle analysis substantiated this finding. ROS generation and superoxide showed association with apoptotic death. The upregulation and overexpression of cleaved poly(ADP-ribose)polymerase-1 (PARP-1) showed the failure of DNA repairing machinery contributes to apoptosis. LC-MS findings show the presence of cytotoxic actives cardamonin and alpinetin.

Conclusions: In summary, this study shows the apoptosis-inducing potential of A. subulatum fruit extracts and confirms DNA damage as one of the causes of cell death. Further explorations using bio-fractionation and in-vivo studies are required to determine the most active constituents in A. subulatum.

Keywords: Amomum subulatum; Apoptosis; Lung cancer; MitoSox; ROS; Superoxide production.

MeSH terms

Antineoplastic Agents, Phytogenic / isolation & purification
Antineoplastic Agents, Phytogenic / pharmacology*
Apoptosis / drug effects
Cell Line, Tumor
DNA Damage / drug effects
Elettaria / chemistry*
Fruit
Humans
Lung Neoplasms / drug therapy*
Lung Neoplasms / pathology
Plant Extracts / pharmacology*
Reactive Oxygen Species / metabolism

Substances

Antineoplastic Agents, Phytogenic
Plant Extracts
Reactive Oxygen Species