Cytotoxic Effects of Plant Sap-Derived Extracellular Vesicles on Various Tumor Cell Types

Abstract

Edible plants have been widely used in traditional therapeutics because of the biological activities of their natural ingredients, including anticancer, antioxidant, and anti-inflammatory properties. Plant sap contains such medicinal substances and their secondary metabolites provide unique chemical structures that contribute to their therapeutic efficacy. Plant extracts are known to contain a variety of extracellular vesicles (EVs) but the effects of such EVs on various cancers have not been investigated. Here, we extracted EVs from four plants—Dendropanax morbifera, Pinus densiflora, Thuja occidentalis, and Chamaecyparis obtusa—that are known to have cytotoxic effects. We evaluated the cytotoxic effects of these EVs by assessing their ability to selectively reduce the viability of various tumor cell types compared with normal cells and low metastatic cells. EVs from D. morbifera and P. densiflora sap showed strong cytotoxic effects on tumor cells, whereas those from T. occidentalis and C. obtusa had no significant effect on any tumor cell types. We also identified synergistic effect of EVs from D. morbifera and P. densiflora saps on breast and skin tumor cells and established optimized treatment concentrations. Our findings suggest these EVs from plant sap as new candidates for cancer treatment.

Extracellular Vesicles from Plants: Current Knowledge and Open Questions

“…The most common method of plant vesicle isolation is differential centrifugation followed by ultracentrifugation [4][5][6][7][8][9][10][11][12]. The starting material can be fruits [4,[6][7][8][9][10], roots [5,13], stems [9,14], leaves [9,[14][15][16], seeds [16], and saps [17]; these matrices can be manually squeezed or using a mixer to obtain the juice. The juice is subjected to several differential centrifugation steps: low-speed centrifugation (about 500-3000× g for 10-15 min) to remove plant fibers and large particles; intermediate speed centrifugation (2000-10,000× g for 20-40 min) to remove large debris and subcellular organelles; and high-speed centrifugation (100,000-150,000× g for 1.5-2 h) to obtain PDEVs pellet.…”

“…For example, Raimondo et al, starting from 240 mL of lemon juice, isolated about 600 µg of nanovesicles [4]. Another group, however, obtained about 10 mg of EVs from 10 g of Dendropanax morbifera sap [17]. In addition to protein quantification, the recovery of EVs can be determined by other techniques, such as cytofluorimetry.…”

“…Several studies have emphasized the anti-cancer properties of EVs derived from different plants, thus enabling them to become potential therapeutic compounds in combination with current treatments in cancer management [4,5,14,[17][18][19]39].…”

Oilseed crop sunflower (Helianthus annuus) as a source of food: Nutritional and health benefits

“…The oral administration of ethanolic extracts of sunflower seeds extract in rats with antihyperglycemic effect has been reported (Saini & Sharma, 2013). Also, the in vivo antiasthmatic assay of aqueous extract from sunflower on ovalbumin‐induced mice and the assessment of their lungs by hematoxylin and eosin staining had revealed the extract potency in reducing asthma effect on the mice (Kim et al., 2020). Similarly, the consumption of sunflower seed and oil would probably reduce major risk factors of asthma or diabetes in humans.…”

Anti-Metastatic Effects of Plant Sap-Derived Extracellular Vesicles in a 3D Microfluidic Cancer Metastasis Model

“…Thus, the inhibitory effect of DMS-EVs on CAFs compared with NFs depends on the concentration of DMS-EVs. In our previous study, LC-MS/MS analysis was performed to investigate the protein composition of DMS-EVs, and we found that plant proteins of DMS-EVs were mainly associated with peroxidase [22]. Peroxidases are one of the plant defense proteins, known as antioxidant enzymes that detoxifie hydrogen peroxide.…”