Active Ingredients from Euodia ruticarpa Steam Distilled Essential Oil Inhibit PC-3 Prostate Cancer Cell Growth via Direct Action and Indirect Immune Cells Conditioned Media In Vitro

Abstract

Active constituents isolated from Euodia ruticarpa (ER) steam distilled essential oil (SDEO) against PC-3 prostate cancer cell growth remain unclear. To clarify the puzzle, ER SDEO was extracted and further resolved into six isolated fractions ERF1–F6 with Sephadex LH-20 gel filtration chromatography to analyze their biological activities. Active ingredients in the isolated fractions were analyzed with GC-MS. Potential isolated fractions were selected to treat PC-3 cells with direct action and indirect treatment by mouse splenocyte- (SCM) and macrophage-conditioned media (MCM). The relationship between PC-3 cell viabilities and corresponding total polyphenols, flavonoid contents as well as Th1/Th2 cytokine profiles in SCM was analyzed using the Pearson product–moment correlation coefficient (r). As a result, ERF1–F3 was abundant in total polyphenols and flavonoids contents with diverse active ingredients. Treatments with ERF1–F3 at appropriate concentrations more or less inhibit PC-3 cell growth in a direct action manner. Only SCM, respectively, cultured with ER SDEO and ERF1–F3 markedly enhanced the effects to inhibit PC-3 cell growth, suggesting that secretions by splenocytes might involve anti-PC-3 effects. There are significantly negative correlations between PC-3 cell viabilities and IL-2, IL-10 as well as IL-10/IL-2 ratios in the corresponding SCM. Total polyphenol and flavonoid contents in the media cultured with ER SDEO isolated fractions positively correlated with IL-10 (Th2) and IL-10/IL-2 (Th2/Th1) cytokine secretion ratios by splenocytes, indicating that polyphenol and flavonoid components in ER SDEO isolated fractions promote Th2-polarized and anti-inflammatory characteristics. These new findings concluded that the inhibitory effects against PC-3 prostate cancer cell growth are attributed to active anti-inflammatory ingredients in ER SDEO and its active ERF1–F3 fractions through direct action and indirect treatment by modulating splenocytes’ cytokine secretion profiles.

Menthone Inhalation Alleviates Local and Systemic Allergic Inflammation in Ovalbumin-Sensitized and Challenged Asthmatic Mice

“…To measure the proliferation of splenocytes, the splenocytes (1 × 10 7 cells/mL, 50 μL/well) were cultured in 96-well plates without or with specific mitogens, including OVA (60 μg/mL, 50 μL/well), LPS (a B-cell mitogen, 5.0 μg/mL, 50 μL/well), and concanavalin A (Con A, a T-cell mitogen, Sigma, L9132, St. Louis, MO, USA; 5.0 μg/mL, 50 μL/well), and the plate was incubated in a humidified incubator at 37 °C, 5% CO 2 , and 95% air for 72 h. The viable cells were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay [ 42 , 43 ]. The viable cells were presented as stimulation index (S.I.)…”

How to Naturally Support the Immune System in Inflammation—Essential Oils as Immune Boosters

“…Essential oils are complex mixtures extracted from different parts of plants (stem, flowers, or leaves) through steam distillation or the use of specific solvents that have been used in traditional medicine for ages [ 31 ]. The most known application of essential oils, i.e., aromatherapy, may successfully improve the quality of life of patients suffering from serious diseases, such as cancer, as it reduces anxiety and pain [ 32 , 33 ].…”

“…Euodia ruticarpa ( E. ruticarpia ) (Rutaceae), also known as Tetradium ruticarpum, but especially its fruit, called Tetradii fructus, Evodiae fructus, or Wu Zhu Yu, is commonly applied in traditional as well as clinical medicine in East Asia, e.g., in Korea, Japan, and China, due to a great variety of health benefits, e.g., anti-inflammatory and anti-cancer properties. It has been used to treat post-eating nausea, vomiting, diarrhea, abdominal pain, headache, pelvic inflammation, or bacterial infections [ 32 , 128 , 129 ]. According to Yeh et al, the main constituents of steam-distilled essential oil, such as 2-(3-methoxyphenyl)-4H-1-benzopyran-4-one, N,N′-diphenyl-1,4-benzenediamine, benzoic acid, N-propylbenzamide, and dipropylene glycol dibenzoate, are responsible for E. ruticarpa’s anti-cancer properties.…”

“…The PC-3 cell line is hormonally independent, so traditional hormonal therapy cannot be applied. In this case, an alternative therapy that fights cancer indirectly via immune cells might be invaluable [ 32 , 134 , 135 ].…”

“… suppresses antigen-induced lymphocyte activation The composition of essential oil from fruit of the plant grown in Kagoshima, Japan/Yamaguchi, Japan: α-Pinene 1.78/1.18 β-Myrcene 2.97/3.54 Limonene 60.30/71.34 β-Phellandrene 8.22/7.27 α-Terpinene 5.12/5.51 p-Cymene 6.08/3.56 γ-Elemene 1.93/- α-terpineol -/1.90 (E,E)-α-farnesene -/1.00 [ 127 , 154 , 155 ] 11. Euodia ruticarpa ( E. ruticarpia ) (Rutaceae) It exhibits anticancer propeties by: increasing the level of IL-1β, TNF-α, IL-6 and IL-10 secreted by macrophages affecting regulation of Th1 (IL-2) and Th2 (IL-10) cytokines production by splenocytes activating NK cells and B cells The composition of essential oil from leaf /fruit: β-myrcene 31.03/38.14 β-phellandrene 18.38/25.89 trans-β-ocimene 3.35/- β-ocimene 3.21/17.82 (E)-4,8-dimethyl-1,3,7-nonatriene 6.17/- caryophyllene 2.21/- E-nerolidol 21.79/- γ-eudesmol 1.09/- β-eudesmol 1.52/- α-eudesmol 2.1/- α-pinene -/1.63 trans-β-ocimene -/12.29 [ 32 , 130 , 131 , 132 , 133 , 134 , 135 , 156 ] 12. Eucalyptus plant (Myrtaceae) Its topical application inhibits edema and enhances vascular permeability in IgE-mediated allergic dermatitis it may stimulate the immune function of the respiratory tract, improves phagocytic activity of macrophages and it can be used as an adjuvant in some infections and inflammatory diseases.…”