Phenylethanoid Glycosides in Natural Product Pharmacology

Phenylethanoid glycosides are a class of naturally occurring secondary metabolites characterised by a hydroxyphenylethyl aglycone linked to one or more sugar moieties via glycosidic bonds. They are ubiquitously found in medicinal plants such as Plantago, Cistanche and Rehmannia species, and have attracted sustained interest for their broad spectrum of bioactivities. Key pharmacological properties include potent antioxidant and anti-inflammatory effects, neuroprotective actions in models of oxidative stress, immunomodulation, cardiovascular protection and cytotoxicity against certain cancer cell lines. At the molecular level, these compounds modulate signalling cascades including PI3K/AKT, MAPK, NF-κB and Nrf2/ARE, which underpin their capacity to attenuate oxidative damage, inhibit pro-inflammatory mediators and induce apoptosis in aberrant cells. Despite their therapeutic promise, many phenylethanoid glycosides suffer from low oral bioavailability and rapid metabolism, prompting research into semi-synthetic derivatives, formulation strategies and delivery systems to enhance stability and target tissue distribution. Collectively, this body of work underscores the global significance of phenylethanoid glycosides as lead structures for drug discovery and as nutraceutical agents.

Research from Nature Portfolio

Recent studies have demonstrated that verbascoside can act as an adjuvant to conventional chemotherapy in colorectal cancer. In vitro investigations revealed that sub-toxic concentrations of verbascoside synergise with 5-fluorouracil to induce G1 cell-cycle arrest and enhance apoptosis through modulation of pro- and anti-apoptotic proteins such as Bax and Bcl-2. Mechanistic analyses indicate a marked suppression of the PI3K/AKT signalling axis, reducing phosphorylation of AKT and thereby sensitising tumour cells to cytotoxic insult. These findings highlight a potential application of phenylethanoid glycosides in overcoming chemoresistance and improving therapeutic indices in oncology.

Phenylethanoid Glycosides in Natural Product Pharmacology publication trend

The graph below shows the total number of articles in phenylethanoid glycosides in natural product pharmacology across all publications each year (not limited to Nature Index journals).

Technical terms

Phenylethanoid glycoside: A natural compound comprising a hydroxyphenylethyl aglycone coupled to sugars via glycosidic bonds, noted for diverse bioactivities.

PI3K/AKT pathway: A intracellular signalling cascade that regulates cell survival, proliferation and metabolism; frequently dysregulated in cancer.

Nrf2/ARE pathway: A transcriptional defence mechanism centred on nuclear factor erythroid 2-related factor 2 and antioxidant response elements, driving expression of cytoprotective enzymes.

Bioavailability: The proportion of an administered compound that reaches the systemic circulation in an active form.

Glycosidic bond: A covalent linkage between a sugar moiety and another functional group, crucial to the structure of glycosides.

Antioxidant: A substance that counteracts oxidative stress by scavenging reactive oxygen species or upregulating endogenous defence systems.

References

1. Phenylethanoid Glycosides: Research Advances in Their Phytochemistry, Pharmacological Activity and Pharmacokinetics. Molecules (2016).
2. Verbascoside: Identification, Quantification, and Potential Sensitization of Colorectal Cancer Cells to 5-FU by Targeting PI3K/AKT Pathway. Scientific Reports (2018).
3. The pharmacokinetic property and pharmacological activity of acteoside: A review. Biomedicine & Pharmacotherapy (2022).
4. Neuroprotective Effects of Four Phenylethanoid Glycosides on H2O2-Induced Apoptosis on PC12 Cells via the Nrf2/ARE Pathway. International Journal of Molecular Sciences (2018).