Aqueous Extract of Cinnamon (Cinnamomum spp.): Role in Cancer and Inflammation

Abstract

Cinnamon (Cinnamomum spp.; family Lauraceae), a plant widely used as a spice and flavoring agent and in the perfume industry, has high therapeutic value. However, the components and chemical properties of cinnamon extracts vary depending on the part of the plant, the method, and the solvent used for extraction. Green extraction methods using safe and green solvents have gained increased interest in recent years. Water is an environmentally friendly and safe green solvent widely used for preparing cinnamon extracts. This review focuses on the various preparation techniques for the aqueous extract of cinnamon, its major bioactive components, and their beneficial roles in different pathological conditions, specifically cancer and inflammation. The aqueous extract of cinnamon contains several bioactive compounds, such as cinnamaldehyde, cinnamic acid, and polyphenols, and exerts anticancer and anti-inflammatory properties by altering key apoptotic and angiogenic factors. The whole extract is a better anticancer and anti-inflammatory agent than the purified fractions, indicating a synergistic effect between various components. Studies have indicated that aqueous cinnamon extract has immense therapeutic potential, and to better understand its synergistic effects, extensive characterization of the aqueous extract and its potential to be used with other therapies should be explored.

Figure 1

Hallmark of cancer cells.

Figure 2

Conventional and green extraction methods.

Figure 3

Summary of the methods used for preparation of aqueous cinnamon extract. Increased temperatures are used for extraction, but there is a lot of variation with respect to heating temperature and duration as seen in the figure. Similarly, even when boiling is used to prepare the extract, lab-specific methods have been used.

Figure 4

Aqueous cinnamon extract has been shown to have anticancer and anti-inflammatory properties. This figure depicts a simplistic view of the molecules downregulated in the process of counteracting cancer and inflammation by aqueous cinnamon extract. NF-kB: nuclear factor kappa light chain enhancer of activated B-cells, AP1: activator protein 1, VEGFR2: vascular endothelial growth factor receptor 2, VEGF: vascular endothelial growth factor, p38-MAPK: p38 mitogen-activated protein kinases, STAT4: signal transducer and activator of transcription 4, HIF-1α: hypoxia-inducible factor 1-alpha, STAT3: signal transducer and activator of transcription 3, and AKT: it refers to protein kinase B (PKB).

Figure 5

Structure of trans cinnamaldehyde [88].

Figure 6

Structure of cinnamic acid [92].

Figure 7

Procyanidin dimers and structures.