Soyasapogenol B Attenuates Laryngeal Carcinoma Progression through Inducing Apoptotic and Autophagic Cell Death

Bridging the Gaps between Plant and Human Health: A Systematic Review of Soyasaponins

Saponins, prominent secondary plant metabolites, are recognized for their roles in plant defense and medicinal benefits. Soyasaponins, commonly derived from legumes, are a class of triterpenoid saponins that demonstrate significant potential for plant and human health applications. Previous research and reviews largely emphasize human health effects of soyasaponins. However, the biological effects of soyasaponins and their implications for plants in the context of human health have not been well-discussed. This review provides comprehensive discussions on the biological roles of soyasaponins in plant defense and rhizosphere microbial interactions; biosynthetic regulation and compound production; immunological effects and potential for therapeutics; and soyasaponin acquisition attributed to processing effects, bioavailability, and biotransformation processes based on recent soyasaponin research. Given the multifaceted biological effects elicited by soyasaponins, further research warrants an integrated approach to understand molecular mechanisms of regulations in their production as well as their applications in plant and human health.

Comprehensive review on signaling pathways of dietary saponins in cancer cells suppression

Nutrigenomics utilizes high-throughput genomic technologies to reveal changes in gene and protein levels. Excitingly, ever-growing body of scientific findings has provided sufficient evidence about the interplay between diet and genes. Cutting-edge research and advancements in genomics, epigenetics and metabolomics have deepened our understanding on the role of dietary factors in the inhibition of carcinogenesis and metastasis. Dietary saponins, a type of triterpene glycosides, are generally found in Platycodon grandifloras, Dioscorea oppositifolia, asparagus, legumes, and sea cucumber. Wealth of information has started to shed light on pleiotropic mechanistic roles of dietary saponins in cancer prevention and inhibition. In this review, we have attempted to summarize the in vitro research of dietary saponins in the last two decades by searching common databases such as Google Scholar, PubMed, Scopus, and Web of Science. The results showed that dietary saponins exerted anti-cancer activities via regulation of apoptosis, autophagy, arrest cell cycle, anti-proliferation, anti-metastasis, and anti-angiogenesis, by regulation of several critical signaling pathways, including MAPK, PI3K/Akt/mTOR, NF-κB, and VEGF/VEGFR. However, there is no data about the dosage of dietary saponins for practical anti-cancer effects in human bodies. Extensive clinical studies are needed to confirm the effectiveness of dietary saponins for further commercial and medical applications.

Biosynthesis of Soyasapogenol B by Engineered Saccharomyces cerevisiae

Soyasapogenol B is an oleanane-type pentacyclic triterpene that has various applications in food and healthcare and has a higher biological activity than soyasaponin. Saccharomyces cerevisiae is a potential platform for terpenoid production with mature genetic tools for metabolic pathway manipulation. In this study, we developed a biosynthesis method to produce soyasapogenol B. First, we expressed β-amyrin synthase derived from Glycyrrhiza glabra in S. cerevisiae to generate β-amyrin, as the precursor of soyasapogenol B. Several different types of promoters were then used to regulate the expression of key genes in the mevalonate pathway (MVA), and this subsequently increased the yield of β-amyrin to 17.6 mg/L, 25-fold more than that produced in the original strain L01 (0.68 mg/L). Then, using the β-amyrin-producing strain, we expressed soyasapogenol B synthases from Medicago truncatula (CYP93E2 and CYP72A61V2) and from G. glabra (CYP93E3 and CYP72A566). Soyasapogenol B yields were then optimized by using soyasapogenol B synthases and cytochrome P450 reductase from G. glabra. The most effective soyasapogenol B production strain was used for fermentation, and the yield of soyasapogenol B reached 2.9 mg/L in flask and 8.36 mg/L in a 5-L bioreactor with fed glucose and ethanol. This study demonstrated the heterologous synthesis of soyasapogenol B in S. cerevisiae using the combined expression of CYP93E3 and CYP72A566 in the synthesis pathway, which significantly increased the production of soyasapogenol B and provides a reference method for the biosynthesis of other triterpenes.

Resveratrol modulates the apoptosis and autophagic death of human lung adenocarcinoma A549 cells via a p53‑dependent pathway: Integrated bioinformatics analysis and experimental validation

Resveratrol (RSV) has been reported to exhibit cytotoxic activity in multiple types of malignant cells; however, the mechanisms underlying the antitumor effects of RSV in non-small-cell lung cancer (NSCLC) cells remain undetermined. Combining bioinformatics analysis with experimental validation, the present study aimed to examine the effects of RSV on the apoptosis and autophagy of A549 NSCLC cells, and to determine the potential underlying molecular mechanisms. Bioinformatics analysis was used to determine the differentially expressed genes (DEGs) and identify the enriched biological functions and pathways associated with these DEGs following RSV treatment. Cell viability was determined by MTT assay, and flow cytometry and TUNEL assay were used to evaluate cell apoptosis. Monodansylcadaverine staining combined with a transmission electron microscope were used to evaluate the extent of autophagy. The expression levels of apoptosis-, autophagy-, or pathway-associated molecular markers were measured by reverse transcription-quantitative PCR and/or western blot analysis. By bioinformatics analysis, a total of 1,031 DEGs were identified in the RSV-treated A549 cells, which were enriched in apoptosis-, or autophagy-related biological functions and the p53 signaling pathway. In validation experiments, RSV significantly reduced cell viability and initiated apoptosis, with an increase in the number of apoptotic cells; it also upregulated cleaved caspase-3 expression and Bax expression, and downregulated the Bcl-2 expression levels. Additionally, there was an increase in the accumulation of green dot-like structures, indicative of autophagic vesicles, observed under a fluorescence microscope, and an increase in the presence of autophagic vacuoles observed using a transmission electron microscope following RSV treatment. Furthermore, the expression levels of the autophagy-related proteins, LC3-II/LC3-I and Beclin-1, were increased and p62 expression was decreased. 3-methyladenine (3-MA), an inhibitor of autophagy, partially reversed the RSV-induced cytotoxic effects, but did not significantly alter the number of apoptotic cells. RSV elevated the p53 levels and decreased the phosphorylated (p-)Mdm2 and p-Akt levels. Pifithrin-α, an inhibitor of p53, partially reduced RSV-induced apoptosis and autophagy. On the whole, the results of the present study demonstrated that RSV initiates the apoptosis and autophagic death of A549 cells via the activation of the p53 signaling pathway, further highlighting the potential of RSV for the treatment of NSCLC.