Anti-Inflammatory and Anti-proliferative Role of Essential Oil of Leaves of Cleistocalyx operculatus (Roxb.) Merr. & Perry.

Background: Phytochemicals have long remained an essential component of the traditional medicine system worldwide. Advancement of research in phytochemicals has led to the identification of novel constituents and metabolites from phytochemicals, performing various vital functions ranging from antimicrobial properties to anticarcinogenic roles. This plant is traditionally used by local people to manage inflammation. In this study, we aim to extract and chemically profile the essential oil from the leaves of Cleistocalyx operculatus (Roxb.) Merr. & Perry and study of the anti-inflammatory and anti-proliferative role of essential oil.

Methods: The hydro distillation method was used for the extraction of essential oil, and the GC-MS was applied for the chemical profiling. The percentage of cell viability was calculated using a crystal violet assay, colony formation assay was performed using Semiquantitative PCR, Propodium iodite staining was used for cell death assay, and Western blotting was used to determine antibodies and proteins. Schrodinger 2015 software was used for molecular docking.

Results: Myrcene, a monoterpene, constitutes 56% of the oil and could be attributed to its anti-inflammatory potential. Treatment of LPS-challenged mouse macrophages RAW264.7 cells with essential oil resulted in a decline in the inflammatory markers, such as IL-1β, TNFα, iNOS, COX-2, and NFκB. Further, essential oil inhibited cancer PC-3, A431, A549, and MCF-7 cell lines at concentrations lower than normal PNT2 and HEK-293 cell lines. This decline in proliferative potential can be attributed to a decline in anti-apoptotic proteins, such as procaspase 3 and PARP, an increase in CKIs, such as p21, and a decline in the Akt signaling responsible for survival.

Conclusion: The essential oil of the plant Cleistocalyx operculatus may be a potential lead for anti-inflammatory and anti-proliferative function.