Frankincense (Boswellia sacra)

 

Abstract

Background

The volatile fraction of frankincense (Boswellia sacra) oleogum was extracted, formulated in nanoemulsion and tested against lung cancer A549 cell line. First, the gum was hydro-distilled to isolate the volatile fraction (essential oil), which was analyzed via gas chromatography to identify its major volatile constituents. Then, the oil was formulated in two water-based nanoemulsions which differ from one another in the presence of propylene glycol (PG), which is used in the formulation step as a co-surfactant. The pure essential oil as well as its major volatile compound (α-pinene), its two nanoemulsions and a reference drug (Doxorubicin) were evaluated against lung cancer A549 cell lines and WI-38 normal lung cells. The evaluation included cytotoxicity (MTT and IC50), apoptosis (flow cytometric analysis) in addition to genetic assessments for some intrinsic and extrinsic genes relevant to apoptosis and survival pathways.

Results

Chromatographic analysis of frankincense essential oil revealed that α-pinene is the major volatile compound which constituent about 60% of that oil. Emulsification of the oil using the low energy technique gave nanoemulsions having major intense particles population (85–90%) with z-average diameter below 20.0 nm. Frankincense oil nanoemulsion fabricated with (PG) showed the best cytotoxic activity toward lung cancer A549 cell compared to PG-free nanoemulsion, α-pinene and the reference drug doxorubicin, along different incubation periods. Flow cytometric analysis also indicated that PG-containing nanoemulsion can induce cancer cells toward apoptosis better than the other formula and the pure oils. The same nanoemulsion was found to upregulate the pro-apoptotic genes [DR5, FAAD, Caspase 8 (Cas8), p53, and Bax] and downregulate the anti-apoptotic and reoccurrence genes (Bcl-2, NF-kB, and STAT-3). Most importantly, the PG-containing nanoemulsion had the least cytotoxic effect on the normal WI-38 lung cells.

Conclusions

These results point out to the potentials of frankincense essential oil (rich in α-pinene) and its PG-nanoemulsion as a promising adjuvant from plant-source to potentiate the activity of the systematic anti-lung cancer drugs.

How does frankincense target cancer cells?

Frankincense targets cancer cells through various mechanisms, particularly in lung cancer treatment. Here's how it works:

Key Components:

α-pinene: A major volatile compound in frankincense essential oil, making up about 60% of the oil.
Boswellic acids: A family of pentacyclic terpenoid molecules found in the non-volatile fraction of frankincense, known for their anti-inflammatory and anti-cancer properties.

Mechanisms of Action:

Inducing Apoptosis: Frankincense essential oil nanoemulsion induces cancer cells to undergo apoptosis (programmed cell death) by upregulating pro-apoptotic genes (DR5, FAAD, Caspase 8, p53, and Bax) and downregulating anti-apoptotic genes (Bcl-2, NF-kB, and STAT-3).
Cytotoxic Activity: Frankincense oil nanoemulsion shows better cytotoxic activity against lung cancer cells compared to pure essential oil and α-pinene.
Inhibiting Cancer Cell Growth: Frankincense has been shown to inhibit the growth of various cancer cells, including lung cancer cells.

Delivery Method:

Nanoemulsion: Formulating frankincense essential oil into nanoemulsions enhances its anti-cancer activity, allowing for better delivery and increased bioavailability. The nanoemulsion particles are small (less than 20 nm) and stable, making them effective in targeting cancer cells ¹.