Therapeutic potential of Curcuma oil and its terpenoids in gynecological cancers

Curcumol: a review of its pharmacology, pharmacokinetics, drug delivery systems, structure-activity relationships, and potential applications

Curcumol (Cur), a guaiane-type sesquiterpenoid hemiketal, is an important and representative bioactive component extracted from the essential oil of the rhizomes of Curcumae rhizoma which is also known as "Ezhu" in traditional Chinese medicine. Recently, Cur has received considerable attention from the research community due to its favorable pharmacological activities, including anti-cancer, hepatoprotective, anti-inflammatory, anti-viral, anti-convulsant, and other activities, and has also exerted therapeutic effect on various cancers, liver diseases, inflammatory diseases, and infectious diseases. Pharmacokinetic studies have shown that Cur is rapidly distributed in almost all organs of rats after intragastric administration with high concentrations in the small intestine and colon. Several studies focusing on structure-activity relationship (SAR) of Cur have shown that some Cur derivatives, chemically modified at C-8 or C-14, exhibited more potent anti-cancer activity and lower toxicity than Cur itself. This review aims to comprehensively summarize the latest advances in the pharmacological and pharmacokinetic properties of Cur in the last decade with a focus on its anti-cancer and hepatoprotective potentials, as well as the research progress in drug delivery system and potential applications of Cur to date, to provide researchers with the latest information, to highlighted the limitations of relevant research at the current stage and the aspects that should be addressed in future research. Our results indicate that Cur and its derivatives could serve as potential novel agents for the treatment of a variety of diseases, particularly cancer and liver diseases.

Natural products targeting the MAPK-signaling pathway in cancer: overview

PURPOSE

This article summarizes natural products that target the MAPK-signaling pathway in cancer therapy. The classification, chemical structures, and anti-cancer mechanisms of these natural products are elucidated, and comprehensive information is provided on their potential use in cancer therapy.

METHODS

Using the PubMed database, we searched for keywords, including "tumor", "cancer", "natural product", "phytochemistry", "plant chemical components", and "MAPK-signaling pathway". We also screened for compounds with well-defined structures that targeting the MAPK-signaling pathway and have anti-cancer effects. We used Kingdraw software and Adobe Photoshop software to draw the chemical compound structural diagrams.

RESULTS

A total of 131 papers were searched, from which 85 compounds with well-defined structures were selected. These compounds have clear mechanisms for targeting cancer treatment and are mainly related to the MAPK-signaling pathway. Examples include eupatilin, carvacrol, oridonin, sophoridine, diosgenin, and juglone. These chemical components are classified as flavonoids, phenols, terpenoids, alkaloids, steroidal saponins, and quinones.

CONCLUSIONS

Certain MAPK pathway inhibitors have been used for clinical treatment. However, the clinical feedback has not been promising because of genomic instability, drug resistance, and side effects. Natural products have few side effects, good medicinal efficacy, a wide range of sources, individual heterogeneity of biological activity, and are capable of treating disease from multiple targets. These characteristics make natural products promising drugs for cancer treatment.

Discovery of plant-derived anti-tumor natural products: Potential leads for anti-tumor drug discovery

Natural products represent a paramount source of novel drugs. Numerous plant-derived natural products have demonstrated potent anti-tumor properties, thereby garnering considerable interest in their potential as anti-tumor drugs. This review compiles an overview of 242 recently discovered natural products, spanning the period from 2018 to the present. These natural products, which include 69 terpenoids, 42 alkaloids, 39 flavonoids, 21 steroids, 14 phenylpropanoids, 5 quinolines and 52 other compounds, are characterized by their respective chemical structures, anti-tumor activities, and mechanisms of action. By providing an essential reference and fresh insights, this review aims to support and inspire researchers engaged in the fields of natural products and anti-tumor drug discovery.

Co-Delivery of Ylang Ylang Oil of Cananga odorata and Oxaliplatin Using Intelligent pH-Sensitive Lipid-Based Nanovesicles for the Effective Treatment of Triple-Negative Breast Cancer

Smart pH-responsive niosomes loaded with either Oxaliplatin (Ox), Ylang ylang essential oil (Y-oil), or co-loaded with both compounds (Ox-Y) (Ox@NSs, Y@NSs, and Ox-Y@NSs, respectively) were formulated utilizing the thin film method. The developed nanocontainers had a spherical morphology with mean particle sizes lower than 170 nm and showed negative surface charges, high entrapment efficiencies, and a pH-dependent release over 24 h. The prepared pH-responsive niosomes' cytotoxicity was tested against the invasive triple-negative breast cancer (MDA-MB-231) cells, compared to free OX and Y-oil. All niosomal formulations loaded with Ox and/or Y-oil significantly improved cytotoxic activity relative to their free counterparts. The Ox-Y@NSs demonstrated the lowest IC50 (0.0002 µg/mL) when compared to Ox@NSs (0.006 µg/mL) and Y@NSs (18.39 µg/mL) or unloaded Ox (0.05 µg/mL) and Y-oil (29.01 µg/mL). In addition, the percentages of the MDA-MB-231 cell population in the late apoptotic and necrotic quartiles were profoundly higher in cells treated with the smart Ox-Y@NSs (8.38% and 5.06%) than those exposed to free Ox (7.33% and 1.93%) or Y-oil (2.3% and 2.13%) treatments. Gene expression analysis and protein assays were performed to provide extra elucidation regarding the molecular mechanism by which the prepared pH-sensitive niosomes induce apoptosis. Ox-Y@NSs significantly induced the gene expression of the apoptotic markers Tp53, Bax, and Caspase-7, while downregulating the antiapoptotic Bcl2. As such, Ox-Y@NSs are shown to activate the intrinsic pathway of apoptosis. Moreover, the protein assay ascertained the apoptotic effects of Ox-Y@NSs, generating a 4-fold increase in the relative protein quantity of the late apoptotic marker Caspase-7. Our findings suggest that combining natural essential oil with synthetic platinum-based drugs in pH-responsive nanovesicles is a promising approach to breast cancer therapy.

A Comparative Study on Chemical Compositions and Biological Activities of Four Amazonian Ecuador Essential Oils: Curcuma longa L. (Zingiberaceae), Cymbopogon citratus (DC.) Stapf, (Poaceae), Ocimum campechianum Mill. (Lamiaceae), and Zingiber officinale Roscoe (Zingiberaceae)

Essential oils (EOs) and their vapour phase of Curcuma longa (Zingiberaceae), Cymbopogon citratus (Poaceae), Ocimum campechianum (Lamiaceae), and Zingiber officinale (Zingiberaceae) of cultivated plants grown in an Amazonian Ecuador area were chemically characterised by Gas Chromatography-Flame Ionization Detector (GC-FID), Gas Chromatography-Mass Spectrometry (GC-MS), and Head Space-Gas Chromatograph-Flame Ionization Detector-Mass Spectrometry (HS-GC-FID-MS).figure The EOs analyses led to the identification of 25 compounds for C. longa (99.46% of the total; ar-turmerone: 23.35%), 18 compounds for C. citratus (99.59% of the total; geraniol: 39.43%), 19 compounds for O. campechianum (96.24% of the total; eugenol: 50.97%), and 28 for Z. officinale (98.04% of the total; α-Zingiberene: 15.45%). The Head Space fractions (HS) revealed C. longa mainly characterised by limonene and 1,8-cineole (37.35%) and α-phellandrene (32.33%); Z. officinale and C. citratus showed camphene (50.39%) and cis-Isocitral (15.27%) as the most abundant compounds, respectively. O. campechianum EO revealed a higher amount of sesquiterpenes (10.08%), mainly characterised by E-caryophyllene (4.95%), but monoterpene fraction remained the most abundant (89.94%). The EOs were tested for antioxidant, antimicrobial, and mutagen-protective properties and compared to the Thymus vulgaris EO as a positive reference. O. campechianum EO was the most effective in all the bioactivities checked. Similar results emerged from assaying the bioactivity of the vapour phase of O. campechianum EO. The antioxidant and antimicrobial activity evaluation of O. campechianum EO were repeated through HP-TLC bioautography assay, pointing out eugenol as the lead compound for bioactivity. The mutagen-protective evaluation checked through Ames's test properly modified evidenced a better capacity of O. campechianum EO compared with the other EOs, reducing the induced mutagenicity at 0.1 mg/plate. However, even with differences in efficacy, the overall results suggest important perspectives for the functional use of the four studied EOs.

Folic Acid-Grafted Chitosan-Alginate Nanocapsules as Effective Targeted Nanocarriers for Delivery of Turmeric Oil for Breast Cancer Therapy

Folate receptors (FRs) highly expressed in breast cancers can be used as a recognized marker for preventing off-target delivery of chemotherapeutics. In this study, folic acid (FA)-grafted chitosan-alginate nanocapsules (CS-Alg-NCs) loaded with turmeric oil (TO) were developed for breast cancer targeting. CS was successfully conjugated with FA via an amide bond with a degree of substitution at 12.86%. The TO-loaded FA-grafted CS-Alg-NCs (TO-FA-CS-Alg-NCs) optimized by Box-Behnken design using response surface methodology had satisfactory characteristics with homogenous particle size (189 nm) and sufficient encapsulation efficiency and loading capacity (35.9% and 1.82%, respectively). In vitro release study of the optimized TO-FA-CS-Alg-NCs showed a sustained TO release following the Korsmeyer-Peppas model with a Fickian diffusion mechanism at pH 5.5 and 7.4. The TO-FA-CS-Alg-NCs showed lower IC₅₀ than ungrafted TO-CS-Alg-NCs and unencapsulated TO against MDA-MB-231 and MCF-7 breast cancer cells, suggesting that FA-CS-Alg-NCs can improve anticancer activity of TO through its active targeting to the high FRs expressing breast cancers.