Objective: This study aimed to determine the cytoprotective potentials of citronella ( Cymbopogon nardus (L.) Rendl.) essential oil (CO) and lemongrass ( Cymbopogon citratus (DC.) Stapf) essential oil (LO). Methods: The essential oils from citronella and lemongrass were obtained by steam-water distillation, then analyzed using Gas Chromatography-Mass Spectrophotometry (GC-MS) to determine the chemical constituents. The antioxidant activity of CO and LO was compared using a total antioxidant capacity kit. The viability of normal kidney epithelial cells Vero and fibroblast NIH-3T3 as the cell models were tested using a trypan blue exclusion assay. The effect of cellular senescence inhibition on both cell models was measured using senescence-associated β-galactosidase (SA-β-gal) staining. The mechanism of action of CO and LO in the protection of cellular damage against doxorubicin was also confirmed through 2’,7’–dichlorofluorescin diacetate (DCFDA) staining to discover the ability to decrease reactive oxygen species (ROS) levels and a gelatin zymography assay to observe the activity of matrix metalloproteinases (MMPs). Results: The major marker components of CO and LO were citronellal and citral, respectively. Both oils showed low cytotoxic activity against Vero and NIH-3T3 cells, with IC 50 values of over 40 µg/mL. LO exhibited higher antioxidant capacity than CO, but there was no effect on the intracellular ROS level of both oils on Vero and NIH-3T3 cells. However, CO and LO decreased cellular senescence induced by doxorubicin exposure on both cells, as well as suppressed MMP-2 expression. Conclusion: Both CO and LO decrease the cellular senescence and MMP-2 expression with less cytotoxic effects on normal cells independently from their antioxidant capacities. The results were expected to support the use of CO and LO as tissue protective and anti-aging agents in maintaining the body’s cellular health against chemotherapeutics or cellular damaging agents.

Many chemotherapeutic agents cause various side effects, including nephrotoxicity. Doxorubicin, for example, increases the level of reactive oxygen species (ROS), leading to cell senescence in the kidneys. Cardamom essential oil (Amomum compactum Soland. ex Maton) contains compounds that exhibit antioxidant activity, such as 1.8-cineole, α-pinene, α-terpineol, and linalool. This study focused on exploring the potency of cardamom essential oil (CEO) as an anti-senescence induced by doxorubicin using Vero cells. CEO was obtained by steam distillation. The cytotoxic assay was carried out using trypan blue exclusion assay. We performed the 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) staining and the senescence-associated beta-galactosidase (SA-β-gal) staining to measure the effect of CEO on intracellular ROS level and cell senescence, respectively. Analysis of the compounds with gas chromatography-mass spectrophotometry (GC-MS), revealed seven compounds with significant abundance, namely 1.8-cineole (50.82%), ß-pinene (12.43%), α-terpineol (8.50%), fenchone (4.10%), α-pinene (4.00%), sabinene (3.00%), and linalool (1.98%). The cytotoxicity assay of CEO on Vero cells showed an IC50 value of 178 μg/mL. Thus, the CEO is considered to be not cytotoxic and safe for normal kidney cells. Concentrations of 50 and 100 μg/mL reduced the senescence induced by doxorubicin. Therefore, the CEO has the potency as a nephroprotective agent in doxorubicin-induced senescence.

BACKGROUND: Cardamom (Amomum cardamom) essential oil (CEO) contains monoterpenes with antioxidant activity and is reported to exhibit anticancer activity against some cancer cell lines. Triple-negative breast cancer (TNBC) has the lowest prognosis among breast cancer types due to its aggressive characteristics. This study was conducted to explore the potency of CEO in inhibiting 4T1 cell proliferation and migration and compared its activity to sappan (Caesalpinia sappan) wood extract (CSE).METHODS: We used the 4T1 cell line as the TNBC cell model and tested the cytotoxicity of CEO by using a trypan blue exclusion assay. We studied the senescence induction ability of CEO using SA-β-Gal assay, the migratory inhibition activity using scratch wound healing assay, and inhibition of matrix metalloproteinase 9 (MMP-9) expression using gelatin zymography. RESULTS: CEO showed cytotoxicity toward 4T1 cells with the IC50 values of 60 µg/mL. CEO at ½ IC50 and IC50 concentration significantly increased cell senescence, but CSE did not. CEO at IC50 also reduced cell ability to migrate and also considerably reduced MMP-9 activity. Moreover, these activities related to the inhibition of the cell metastasis process were weaker compared than that of CSE.CONCLUSION: CEO showed potency as a chemopreventive agent on the TNBC 4T1 cell line model with moderate cytotoxicity. CEO induced 4T1 cell senescence, inhibited cell migration and suppressed MMP-9 expression.KEYWORDS: Amomum cardamom, Caesalpinia sappan, 4T1, senescence, cell migration, triple-negative breast cancer