Toxicity, Teratogenicity and Anti-cancer Activity of α-solanine: A Perspective on Anti-cancer Potential

Effects of α‑solanine on human head and neck squamous cell carcinoma cells and human umbilical vein endothelial cells in vitro

α-solanine is a glycoalkaloid that is commonly found in nightshades (Solanum) and has a toxic effect on the human organism. Among other things, it is already known to inhibit tumor cell proliferation and induce apoptosis in tumor cell lines. Due to its potential as a tumor therapeutic, the current study investigated the effect of α-solanine on head and neck squamous cell carcinoma (HNSCC). In addition, genotoxic and antiangiogenic effects on human umbilical vein endothelial cells (HUVECs) were evaluated at subtoxic α-solanine concentrations. Cytotoxicity and apoptosis rates were measured in two human HNSCC cell lines (FaDu pharynx carcinoma cells and CAL-33 tongue carcinoma cells), as well as in HUVECs. MTT and Annexin V analyses were performed 24 h after α-solanine treatment at increasing doses up to 30 µM to determine cytotoxic concentrations. Furthermore, genotoxicity at subtoxic concentrations of 1, 2, 4 and 6 µM in HUVECs was analyzed using single-cell gel electrophoresis (comet assay). The antiangiogenic effect on HUVECs was evaluated in the capillary tube formation assay. The MTT assay indicated an induction of concentration-dependent viability loss in FaDu and CAL-33 cancer cell lines, whereas the Annexin V test revealed α-solanine-induced cell death predominantly independent from apoptosis. In HUVECs, the cytotoxic effect occurred at lower concentrations. No genotoxicity or inhibition of angiogenesis were detected at subtoxic doses in HUVECs. In summary, α-solanine had a cytotoxic effect on both malignant and non-malignant cells, but this was only observed at higher concentrations in malignant cells. In contrast to existing data in the literature, tumor cell apoptosis was less evident than necrosis. The lack of genotoxicity and antiangiogenic effects in the subtoxic range in benign cells are promising, as this is favorable for potential therapeutic applications. In conclusion, however, the cytotoxicity in non-malignant cells remains a severe hindrance for the application of α-solanine as a therapeutic tumor agent in humans.

Wnt/β-catenin signaling pathway inhibitors, glycyrrhizic acid, solanine, polyphyllin I, crocin, hypericin, tubeimoside-1, diosmin, and rutin in medicinal plants have better binding affinities and anticancer properties: Molecular docking and ADMET study

Wnt/β-catenin signaling pathway plays a role in cancer development, organogenesis, and embryogenesis. The abnormal activation promotes cancer stem cell renewal, proliferation, and differentiation. In the present study, molecular docking simulation and ADMET studies were carried out on selected bioactive compounds in search of β-catenin protein inhibitors for drug discovery against cancer. Blind docking simulation was performed using PyRx software on Autodock Vina. β-catenin protein (PDB ID: 1jdh) and 313 bioactive compounds (from PubChem database) with selected standard anticancer drugs were used for molecular docking. The ADMET properties of the best-performing compounds were calculated using SwissADME and pkCMS web servers. The results obtained from the molecular docking study showed that glycyrrhizic acid, solanine, polyphyllin I, crocin, hypericin, tubeimoside-1, diosmin, and rutin had the best binding interactions with β-catenin protein based on their binding affinities. Glycyrrhizic acid and solanine had the same and lowest binding energy of -8.5 kcal/mol. This was followed by polyphyllin I with -8.4 kcal/mol, and crocin, hypericin, and tubeimoside-1 which all had a binding energy of 8.1 kcal/mol. Other top-performing compounds include diosmin and rutin with binding energy of -8.0 kcal/mol. The ADMET study revealed that the following compounds glycyrrhizic acid, solanine, polyphyllin I, crocin, hypericin, tubeimoside-1, diosmin, rutin, and baicalin all violated Lipinski's rule of 5 which implies poor oral bioavailability. However, based on the binding energy score, it was suggested that these pharmacologically active compounds are potential molecules to be tested against cancer.

Biosynthesis, distribution, nutritional and organoleptic properties of bitter compounds in fruit and vegetables

Compounds that confer a bitter taste on fruits and vegetables (FAVs) play crucial roles in both plant defense and health promotion. This review details the current knowledge of the distribution, properties (toxicity, pharmacological effects and receptors) and environmental plant responses relating to the biosynthesis, catabolism and transcriptional regulation of 53 bitter plant metabolites in diverse species of FAVs. Some bitter compounds, such as flavonoids, are common in all plant species and make a minor contribution to bitter flavor, but many are synthesized only in specific taxa. They make major contributions to the bitter taste of the corresponding species and some also have significant pharmacological effects. Levels of bitter metabolites are genetically determined, but various environmental cues can affect their final concentration during preharvest development and postharvest storage processes. Molecular approaches are helping to unravel the mechanisms of biosynthesis and regulation of bitter compounds in diverse crop species. This review not only discusses the theoretical basis for utilizing breeding programs and other agricultural technologies to produce FAVs with improved safety, favorable taste and healthier profiles, but also suggests new directions for the utilization of bitter compounds in FAVs for the development of natural pesticides and health-promoting medicines.

Advances in the development of biopolymeric adsorbents for the extraction of metabolites from nutraceuticals with emphasis on Solanaceae and subsequent pharmacological applications

Biopolymers are renowned for their sustainable, biodegradable, biocompatible and most of them have antitoxic characteristics. These versatile naturally derived compounds include proteins, polynucleotides (RNA and DNA) and polysaccharides. Cellulose and chitosan are the most abundant polysaccharides. Proteins and polysaccharides have been applied as emulsifiers. Additional applications of proteins and polysaccharides include cosmetics, food and wastewater treatment for adsorption of dyes and pesticides. However, more interesting applications of biopolymers are emerging, such as use in transport systems for delivery of plant derived nutraceuticals to sites of inflammation, due to its inherent ability to immobilize different biological and chemical systems. This review aims to give a summary on new trends and complement what is already known in the development of polysaccharides and proteins as adsorbents of nutraceutical compounds. The application of polysaccharides/protein containing the adsorbed Solanum derived nutraceutical compounds for drug deliveryis also reviewed.

Functional relationship of vegetable colors and bioactive compounds: Implications in human health

Vegetables are essential protective diet ingredients that supply ample amounts of minerals, vitamins, carbohydrates, proteins, dietary fiber, and various nutraceutical compounds for protection against various disease conditions. Color is the most important quality parameter for the farmers to access the harvest maturity while for the consumer's reliable indices to define acceptability or rejection. The colored vegetables contain functional compounds like chlorophylls, carotenoids, betalains, anthocyanins, etc. well recognized for their antioxidant, antimicrobial, hypolipidemic, neuroprotective, antiaging, diuretic, and antidiabetic properties. Recently, there has been a shift in food consumption patterns from processed to semi-processed or fresh fruits and vegetables to ensure a healthy disease-free life. This shifted the focus of agriculture scientists and food processors from food security to nutrition security. This has resulted in recent improvements to existing crops like blue tomato, orange cauliflower, colored and/or black carrots, with improved color, and thus enriched bioactive compounds. Exhaustive laboratory trials though are required to document and establish their minimum effective concentrations, bioavailability, and specific health benefits. Efforts should also be directed to breed color-rich cultivars or to improve the existing varieties through conventional and molecular breeding approaches. The present review has been devoted to a better understanding of vegetable colors with specific health benefits and to provide in-hand information about the effect of specific pigment on body organs, the effect of processing on their bioavailability, and recent improvements in colors to ensure a healthy lifestyle.