Screening of Hibiscus and Cinnamomum Plants and Identification of Major Phytometabolites in Potential Plant Extracts Responsible for Apoptosis Induction in Skin Melanoma and Lung Adenocarcinoma Cells

Therapeutic Implications of Dietary Polyphenols-Loaded Nanoemulsions in Cancer Therapy

Cancer is one of the major causes of death worldwide, even the second foremost cause related to non-communicable diseases. Cancer cells typically possess several cellular and biological processes including, persistence, propagation, differentiation, cellular death, and expression of cellular-type specific functions. The molecular picture of carcinogenesis and progression is unwinding, and it appears to be a tangled combination of processes occurring within and between cancer cells and their surrounding tissue matrix. Polyphenols are plant secondary metabolites abundant in fruits, vegetables, cereals, and other natural plant sources. Natural polyphenols have implicated potential anticancer activity by various mechanisms involved in their antitumor action, including modulation of signaling pathways majorly related to cellular proliferation, differentiation, relocation, angiogenesis, metastatic processes, and cell death. The applications of polyphenols have been limited due to the hydrophobic nature and lower oral bioavailability that could be possibly overcome through encapsulating them into nanocarrier-mediated delivery systems, leading to improved anticancer activity. Nanoemulsions (NEs) possess diverse feasible properties, including greater surface area, modifiable surficial charge, higher half-life, site-specific targeting, and formulation imaging capability necessary to create a practical therapeutic impact, and have drawn increased attention in cancer therapy research. This review has summarized and discussed the basic concepts, classification, delivery approaches, and anticancer mechanism of various polyphenols and polyphenols-encapsulated nanoemulsions with improved cancer therapy.

Advances in Biosynthesis and Pharmacological Effects of Cinnamomum camphora (L.) Presl Essential Oil

Cinnamomum camphora (L.) Presl essential oil (CCEO) is a volatile oil with aroma and is extracted from various tissues of Cinnamomum camphora. It is traditionally used as a spice, preservative, as an anti-inflammatory and for sterilization. Terpenoids are the main active components in CCEO. Based on currently available research, considerable effort is still needed to study the biosynthesis and regulation of terpenoids in CCEO. In this review, the research progress related to terpenoid biosynthesis and bioactivity in CCEO in recent years is summarized, with the data compiled and presented mainly from online resources such as PubMed, Scopus and CNKI in China up to May 2022. The research advances related to key enzymes in the terpenoid biosynthesis pathway are mainly discussed. Previous studies have isolated some genes encoding key enzymes involved in terpenoid biosynthesis; however, among these genes, only a few TPS genes have been verified to catalyze the production of terpenoid synthases at the protein level. Most genes encoding key enzymes have been cloned and isolated, but no transgenic experiments have been carried out to verify gene function. In-depth study of the biosynthesis of terpenoids in CCEO may contribute to a better understanding of the differential accumulation of terpenoids in different types of C. camphora and provide reference for improving terpenoid content in CCEO.

Suppression of Melanoma Growth in a Murine Tumour Model Using Orthosiphon stamineus Benth. Extract Loaded in Ethanolic Phospholipid Vesicles (Spherosome

BACKGROUND

Orthosiphon stamineus Benth (O.S) is a traditional south-east Asian herb. The extract of O.S is used in the formulation of ethanolic nanolipid vesicle system to have considerable potential for tumour therapeutics.

METHOD

The research objective is to develop and characterise the anticancer and antiangiogenic effect of O.S extract in the form of nano-ethanolic spherosomes (ESP) using phospholipids in melanoma. Spherosomes formulation of O.S was developed using the thin-film re-hydration method and converted to gel using Acrypol 1%. The formulations were subjected to optimisation and physical-chemical characterisations like particle size, surface charge, DSC, FTIR, TEM. Cytotoxicity of O.S and ESP were studied using an endothelial cell line (EA. hy926). Furthermore, anti-melanoma effect of O.S spherosome gel was studied in albino mice after topical administration.

RESULTS

ESP-6 with the ratio of extract (O.S): cholesterol: phospholipid (1: 6: 0.5) showed the highest entrapment efficiency (80.56 ± 0.84%) using ultraviolet spectroscopy. In-vivo permeation/penetration studies revealed deeper absorption of ESP-6 compared with a hydroethanolic gel of O.S. In-vitro and in vivo anti-melanoma studies demonstrated the significant tumour-suppressing effect of ESP-6 on murine melanoma. Percentage inhibition of tumour growth by O.S and ESP-6 at 3000 mg/kg showed 63.98 ± 7.86% and 87.76 ± 7.90%, respectively.

CONCLUSION

Spherosome vesicles were developed with a smooth surface. The results demonstrated that O.S extract showed no toxicity when tested on the endothelial cell line. O.S loaded in spherosomes has the potential to lower the growth of melanoma in mice. The spherosomes loaded with O.S do not promote tumour growth or act as antiangiogenetic in melanoma.