Anticancer activity evaluation of the solanum glycoalkaloid solamargine. Triggering apoptosis in human hepatoma cells

Ethnomedicinal Usage, Phytochemistry and Pharmacological Potential of Solanum surattense Burm. f

Solanum surattense Burm. f. is a significant member of the Solanaceae family, and the Solanum genus is renowned for its traditional medicinal uses and bioactive potential. This systematic review adheres to PRISMA methodology, analyzing scientific publications between 1753 and 2023 from B-on, Google Scholar, PubMed, Science Direct, and Web of Science, aiming to provide comprehensive and updated information on the distribution, ethnomedicinal uses, chemical constituents, and pharmacological activities of S. surattense, highlighting its potential as a source of herbal drugs. Ethnomedicinally, this species is important to treat skin diseases, piles complications, and toothache. The fruit was found to be the most used part of this plant (25%), together with the whole plant (22%) used to treat different ailments, and its decoction was found to be the most preferable mode of herbal drug preparation. A total of 338 metabolites of various chemical classes were isolated from S. surattense, including 137 (40.53%) terpenoids, 56 (16.56%) phenol derivatives, and 52 (15.38%) lipids. Mixtures of different parts of this plant in water-ethanol have shown in vitro and/or in vivo antioxidant, anti-inflammatory, antimicrobial, anti-tumoral, hepatoprotective, and larvicidal activities. Among the metabolites, 51 were identified and biologically tested, presenting antioxidant, anti-inflammatory, and antitumoral as the most reported activities. Clinical trials in humans made with the whole plant extract showed its efficacy as an anti-asthmatic agent. Mostly steroidal alkaloids and triterpenoids, such as solamargine, solanidine, solasodine, solasonine, tomatidine, xanthosaponin A-B, dioscin, lupeol, and stigmasterol are biologically the most active metabolites with high potency that reflects the new and high potential of this species as a novel source of herbal medicines. More experimental studies and a deeper understanding of this plant must be conducted to ensure its use as a source of raw materials for pharmaceutical use.

Solamargine improves the therapeutic efficacy of anti-PD-L1 in lung adenocarcinoma by inhibiting STAT1 activation

OBJECTIVE

The effect of solamargine on lung adenocarcinoma and its effect on STAT1 signaling pathway mediated immune escape were studied through network pharmacology and in vitro and in vivo experiments.

METHODS

The solamargine targets were screened using the TCMSP and the LUAD targets were screened using the GeneCard, OMIM, PharmGkb, TTD and DrugBank databases. PPI network analysis and target prediction were performed using GO and KEGG. Colony formation assay, EDU staining, wound healing, transwell assay, Hoechst and flow cytometry were used to detect the effects of solamargine on the proliferation, migration and apoptosis of LUAD. Western blotting (WB) and quantitative reverse transcription polymerase chain reaction (RT-qPCR) were used to detect P-STAT1 and PD-L1 expression. And immunofluorescence was used to detect P-STAT1 expression. In vivo experiments, C57BL/6 mice were divided into control group, low concentration group, high concentration group, positive control group and combination group. Every other day, following seven consecutive doses, the size of the tumor was assessed. Finally, the expressions of P-STAT1, STAT1, PD-L1 and apoptosis index proteins were detected by WB.

RESULTS

The anti-LUAD effect of solamargine was found by wound healing, colony formation assay, transwell assay, hoechst and EdU staining. The results of network pharmacological analysis showed that solamargine could suppress STAT1 expression level. Further enrichment assay of STAT1 showed that STAT1 was associated with immune-related pathways. In addition, molecular signal analysis by WB and RT-qPCR indicated that solamargine could reduce the expression levels of P-STAT1 and PD-L1 in a concentration-dependent manner. According to the results of in vivo assays, combination of solamargine and immune checkpoint inhibitors (ICIs) durvalumab could significantly inhibit the growth of Lewis transplanted tumors in C57BL/6 mice, and no toxic side effect was recoded.

CONCLUSION

These results indicated that solamargine could inhibit the proliferation and promote the apoptosis of LUAD. It also could reduce the expression level of P-STAT1 protein and inhibit the expression level of PD-L1. At the same time, the combination with the ICIs can better block the expression of PD-L1 in cells, thereby inhibiting the immune escape pathway of tumor cells and achieving anti-tumor effects. This study proposed a novel combined therapeutic approach, involving the inhibition of STAT1 by solamargine in conjunction with ICIs.

Unleashed Treasures of Solanaceae: Mechanistic Insights into Phytochemicals with Therapeutic Potential for Combatting Human Diseases

Plants that possess a diverse range of bioactive compounds are essential for maintaining human health and survival. The diversity of bioactive compounds with distinct therapeutic potential contributes to their role in health systems, in addition to their function as a source of nutrients. Studies on the genetic makeup and composition of bioactive compounds have revealed them to be rich in steroidal alkaloids, saponins, terpenes, flavonoids, and phenolics. The Solanaceae family, having a rich abundance of bioactive compounds with varying degrees of pharmacological activities, holds significant promise in the management of different diseases. Investigation into Solanum species has revealed them to exhibit a wide range of pharmacological properties, including antioxidant, hepatoprotective, cardioprotective, nephroprotective, anti-inflammatory, and anti-ulcerogenic effects. Phytochemical analysis of isolated compounds such as diosgenin, solamargine, solanine, apigenin, and lupeol has shown them to be cytotoxic in different cancer cell lines, including liver cancer (HepG2, Hep3B, SMMC-772), lung cancer (A549, H441, H520), human breast cancer (HBL-100), and prostate cancer (PC3). Since analysis of their phytochemical constituents has shown them to have a notable effect on several signaling pathways, a great deal of attention has been paid to identifying the biological targets and cellular mechanisms involved therein. Considering the promising aspects of bioactive constituents of different Solanum members, the main emphasis was on finding and reporting notable cultivars, their phytochemical contents, and their pharmacological properties. This review offers mechanistic insights into the bioactive ingredients intended to treat different ailments with the least harmful effects for potential applications in the advancement of medical research.

Solanum nigrum Fruit Extract Modulates Immune System Activity of Mealworm Beetle, Tenebrio molitor L

Here, we report the first evidence concerning the modulation of insect immune system activity after applying Solanum nigrum fruit extract (EXT). We focused on two main issues: (1) is EXT cytotoxic for Tenebrio molitor haemocytes? and (2) how EXT affects the basic immune mechanisms of T. molitor. The results indicate cytotoxic action of 0.01 and 0.1% EXT on beetle haemocytes. Both the injection of EXT and incubating haemocytes with the EXT solution on microscopic slides significantly increased the number of apoptotic cells. However, 24 h after injection of 0.1% EXT cytotoxic effect of the tested extract probably was masked by the increased number of circulating haemocytes. Application of 0.01 and 0.1% EXT led to impairment of the activity of basic immune mechanisms such as phenoloxidase activity and the lysozyme-like antimicrobial activity of T. molitor haemolymph. Moreover, the EXT elicited significant changes in the expression level of selected immune genes. However, some of the immunomodulatory effects of EXT were different in beetles with and without an activated immune system. The obtained results are an essential step toward a complete understanding of the EXT mode of action on the T. molitor physiology and its potential usage in pest control.

Virtual Screening of Alkaloid and Terpenoid Inhibitors of SMT Expressed in Naegleria sp

The pathogenic form of thermophilic Naegleria sp. i.e., Naegleria fowleri, also known as brain eating amoeba, causes primary amoebic encephalitis (PAM) with a >97% fatality rate. To date, there are no specific drugs identified to treat this disease specifically. The present antimicrobial combinatorial chemotherapy is hard on many patients, especially children. Interestingly, Naegleria fowleri has complex lipid biosynthesis pathways like other protists and also has a strong preference to utilize absorbed host lipids for generating energy. The ergosterol biosynthesis pathway provides a unique drug target opportunity, as some of the key enzymes involved in this pathway are absent in humans. Sterol 24-C Methyltransferase (SMT) is one such enzyme that is not found in humans. To select novel inhibitors for this enzyme, alkaloids and terpenoids inhibitors were screened and tested against two isozymes of SMT identified in N. gruberi (non-pathogenic) as well as its homolog found in yeast, i.e., ERG6. Five natural product derived inhibitors i.e., Cyclopamine, Chelerythrine, Berberine, Tanshinone 2A, and Catharanthine have been identified as potential drug candidates based on multiple criteria including binding affinity, ADME scores, absorption, and, most importantly, its ability to cross the blood brain barrier. This study provides multiple leads for future drug exploration against Naegleria fowleri.

Identification of solamargine as a cisplatin sensitizer through phenotypical screening in cisplatin-resistant NSCLC organoids

Although Cisplatin (DDP) is a widely used first-line chemotherapy medication, DDP resistance is one of the main causes of treatment failure in advanced lung cancer. Therefore, it is urgent to identify DDP sensitizers and investigate the underlying molecular mechanisms. Here we utilized DDP-resistant organoids established from tumor biopsies of patients with relapsed lung cancers. In this study, we identified Solamargine as a potential DDP sensitizer through screening a natural product library. Mechanically, Solamargine induced G0/G1-phase arrest and apoptosis in DDP-resistant lung cancer cell lines. Gene expression analysis and KEGG pathway analysis indicated that the hedgehog pathway was suppressed by Solamargine. Moreover, Gli responsive element (GRE) reporter gene assay and BODIPY-cyclopamine binding assay showed that Solamargine inhibited the hedgehog pathway via direct binding to SMO protein. Interestingly, Solamargine and DDP showed a synergetic effect in inhibiting DDP-resistant lung cancer cell lines. Taken together, our work herein revealed Solamargine as a hedgehog pathway inhibitor and DDP-sensitizer, which might provide a new direction for further treatment of advanced DDP-resistant lung cancer patients.

Solamargine Inhibits the Development of Hypopharyngeal Squamous Cell Carcinoma by Decreasing LncRNA HOXA11-As Expression

Hypopharyngeal squamous cell carcinoma (HSCC) is one of the high mortality cancers with a poor prognosis, which is driving the development of new chemotherapeutic agents. We identified the anticancer effects of a natural compound, solamargine (SM), on FaDU cells and explored its mechanism in terms of non-coding RNA. It was observed that SM inhibited the proliferation of FaDU cells with an IC₅₀ of 5.17 μM. High-throughput sequencing data revealed that lncRNA HOXA11-AS was significantly downregulated in cells co-incubated with SM. Further assays demonstrated that SM-induced downregulation of lncRNA HOXA11-AS showed important implications for apoptosis. Given the properties of HOXA11-AS as a miR-155 sponge, we further confirmed that SM upregulated the expression of miR-155 in FaDU cells. C-Myc is a transcription factor that regulates cell differentiation and apoptosis, whose mRNA is considered to be targeted by miR-155. We showed that c-Myc expression was downregulated by SM and accompanied by increased apoptosis, which was consistent with the findings of transcriptome sequencing. Furthermore, SM administration suppressed xenograft tumor growth in a xenograft mouse model in vivo. In the light of the aforementioned findings, our results suggested that SM downregulated the expression of HOXA11-AS, which in turn induces apoptosis by downregulating c-Myc in FaDU, providing evidence for the anticancer effect of SM on HSCC and uncovering the effect of SM on non-coding RNAs as, at least partly, a mechanism of action.

Influence of potato variety on polyphenol profile composition and glycoalcaloid contents of potato juice

The results of studies published in recent years indicate the broad biological activity of potato juice (PJ), which is a byproduct of the starch production process. Among the most frequently described activities are anti-inflammatory, antioxidant, and cytotoxic effects. Nevertheless, this waste juice is produced by the processing of many varieties of potatoes with different proportions, which does not allow to conclude on the biological activity of individual varieties. This article is a report on the antioxidant activity of PJ from seven selected potato varieties, their profile of polyphenolic compounds, and the content of glycoalkaloids (GAs). The use of similar cultivation conditions allowed to eliminate the influence of environmental factors on the content of the analyzed compounds. The influence of PJ on the growth of probiotic, commensal, and pathogenic bacteria was also assessed. It was shown that the varieties significantly influenced the differences in antioxidant activity as well as the content of GAs, but despite the observed differences, none of them showed antimicrobial activity. Therefore, it can be concluded that an appropriately selected variety will make it possible to obtain PJ that will be characterized by high antioxidant activity and, at the same time, will be safe from the toxicological point of view.

Chemical Synthesis of Saponins

Saponins are a large family of amphiphilic glycosides of steroids and triterpenes found in plants and some marine organisms. By expressing a large diversity of structures on both sugar chains and aglycones, saponins exhibit a wide range of biological and pharmacological properties and serve as major active principles in folk medicines, especially in traditional Chinese medicines. Isolation of saponins from natural sources is usually a formidable task due to the microheterogeneity of saponins in Nature. Chemical synthesis can provide access to large amounts of natural saponins as well as congeners for understanding their structure-activity relationships and mechanisms of action. This article presents a comprehensive account on chemical synthesis of saponins. First highlighted are general considerations on saponin synthesis, including preparation of aglycones and carbohydrate building blocks, assembly strategies, and protecting-group strategies. Next described is the state of the art in the synthesis of each type of saponins, with an emphasis on those representative saponins having sophisticated structures and potent biological activities.

Chemical synthesis of saponins: An update

Saponins, as secondary metabolites in terrestrial plants and marine invertebrate, constitute one of the largest families of natural products. The long history of folk medicinal applications of saponins makes them attractive candidates for innovative drug design and development. Chemical synthesis has become a practical alternative to the availability of the natural saponins and their modified analogs, so as to facilitate SAR studies and the discovery of optimal structures for clinical applications. The recent achievements in the synthesis of these complex saponins reflect the advancements of both steroid/triterpene chemistry and carbohydrate chemistry. This chapter provides an updated review on the chemical synthesis of natural saponins, covering the literature from 2014 to 2020.

Determination of Antioxidant Activity by Oxygen Radical Absorbance Capacity (ORAC-FL), Cellular Antioxidant Activity (CAA), Electrochemical and Microbiological Analyses of Silver Nanoparticles Using the Aqueous Leaf Extract of Solanum mammosum L

PURPOSE

The importance of studying polyphenolic compounds as natural antioxidants has encouraged the search for new methods of analysis that are quick and simple. The synthesis of silver nanoparticles (AgNPs) using plant extracts has been presented as an alternative to determine the total polyphenolic content and its antioxidant activity.

METHODS

In this study, aqueous leaf extract of Solanum mammosum, a species of plant endemic to South America, was used to produce AgNPs. The technique of oxygen radical absorption capacity using fluorescein (ORAC-FL) was used to measure antioxidant activity. The oxidation of the 2´,7´-dichlorodihydrofluorescein diacetate (DCFH2-DA) as fluorescent probe was used to measure cellular antioxidant activity (CAA). Electrochemical behavior was also examined using differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Total polyphenolic content (TPH) was analyzed using the Folin-Ciocalteu method, and the major polyphenolic compound was analyzed by high performance liquid chromatography with diode array detector (HPLC/DAD). Finally, a microbial analysis was conducted using Escherichia coli and Bacillus sp.

RESULTS

The average size of nanoparticles was 5.2 ± 2.3 nm measured by high-resolution transmission electron microscopy (HR-TEM). The antioxidant activity measured by ORAC-FL in the extract and nanoparticles were 3944 ± 112 and 637.5 ± 14.8 µM ET/g of sample, respectively. Cellular antioxidant activity was 14.7 ± 0.2 for the aqueous extract and 12.5 ± 0.2 for the nanoparticles. The electrochemical index (EI) was 402 μA/V for the extract and 324 μA/V for the nanoparticles. Total polyphenolic content was 826.6 ± 20.9 and 139.7 ± 20.9 mg EGA/100 g of sample. Gallic acid was the main polyphenolic compound present in the leaf extract. Microbiological analysis revealed that although leaf extract was not toxic for Escherichia coli and Bacillus sp., minor toxic activity for AgNPs was detected for both strains.

CONCLUSION

It is concluded that the aqueous extract of the leaves of S. mammosum contains nontoxic antioxidant compounds capable of producing AgNPs. The methods using AgNPs can be used as a fast analytical tool to monitor the presence of water-soluble polyphenolic compounds from plant origin. Analysis and detection of new antioxidants from plant extracts may be potentially applicable in biomedicine.

Membrane Filtration-Assisted Enzymatic Hydrolysis Affects the Biological Activity of Potato Juice

The results of recently published studies indicate that potato juice is characterized by interesting biological activity that can be particularly useful in the case of gastrointestinal symptoms. Moreover, the studies also described the high nutritional value of its proteins. This article is a report on the impact of the enzymatic hydrolysis of proteins combined with membrane filtration. The obtained potato juice protein hydrolysate (PJPH) and its concentrate (cPJPH) were characterized in terms of their nutritional value and biological activity. The amino acid profile and scoring, the content of mineral compounds, and the antioxidant and in vitro cytotoxic activity were assessed. The study proved that the antioxidant activity of PJPH is higher than that of fresh potato juice, and the cytotoxicity against human gastric carcinoma cell line (Hs 746T), human colon cancer cell line (Caco-2), human colorectal adenocarcinoma cell line (HT-29), and human normal colon mucosa cell line (CCD 841 CoN) showed biological activity specifically targeted against cancer cells. Therefore, it can be concluded that the membrane filtration-assisted enzymatic hydrolysis of potato juice proteins may increase their biological activity and allow for potato juice to be used in the production of medicinal preparations.

Cytotoxic and chemosensitizing effects of glycoalkaloidic extract on 2D and 3D models using RT4 and patient derived xenografts bladder cancer cells

Glycoalkaloids have been widely demonstrated as potential anticancer agents. However, the chemosensitizing effect of these compounds with traditional chemotherapeutic agents has not been explored yet. In a quest for novel effective therapies to treat bladder cancer (BC), we evaluated the chemosensitizing potential of glycoalkaloidic extract (GE) with cisplatin (cDDP) in RT4 and PDX cells using 2D and 3D cell culture models. Additionally, we also investigated the underlying molecular mechanism behind this effect in RT4 cells. Herein, we observed that PDX cells were highly resistant to cisplatin when compared to RT4 cells. IC50 values showed at least 2.16-folds and 1.4-folds higher in 3D cultures when compared to 2D monolayers in RT4 cells and PDX cells, respectively. GE + cDDP inhibited colony formation (40%) and migration (28.38%) and induced apoptosis (57%) in RT4 cells. Combination therapy induced apoptosis by down-regulating the expression of Bcl-2 (p < 0.001), Bcl-xL (p < 0.001) and survivin (p < 0.01), and activating the caspase cascade in RT4 cells. Moreover, decreased expression of MMP-2 and 9 (p < 0.01) were observed with combination therapy, implying its effect on cell invasion/migration. Furthermore, we used 3D bioprinting to grow RT4 spheroids using sodium alginate-gelatin as a bioink and evaluated the effect of GE + cDDP on this system. Cell viability assay showed the chemosensitizing effect of GE with cDDP on bio-printed spheroids. In summary, we showed the cytotoxicity effect of GE on BC cells and also demonstrated that GE could sensitize BC cells to chemotherapy.

Assessing the cytotoxic potential of glycoalkaloidic extract in nanoparticles against bladder cancer cells

OBJECTIVE

This study proposed to use the nanotechnology to deliver glycoalkaloidic extract (AE) to bladder cancer cells, evaluating their activity in 2D and 3D models and the biological mechanism of cell death.

METHODS

NPs were prepared by nanoprecipitation method using polylactic acid (PLA) and characterized considering their size, charge, particle concentration and stability. The cytotoxicity was evaluated in 2D and 3D model, and the apoptosis and cell cycle were investigated using flow cytometry.

KEY FINDINGS

NPs loading AE (NP-AE) had diameter around 125 ± 6 nm (PdI <0.1) and negative charge. The encapsulation efficiency of SM and SS was higher than 85% for both compounds. The obtained formulation showed a significant in-vitro cytotoxic effect against RT4 cells in a dose-dependent manner with IC₅₀ two fold lower than the free AE. The cytotoxic effect of NP-AE was mediated by apoptosis and cell cycle arrested in the S phase. RT4 cells cultured under 3D conditions exhibited a higher resistance to the treatments (IC₅₀ ~ three fold higher than in 2D cell culture).

CONCLUSION

The NP-AE might be a promising nanocarrier to load and deliver glycoalkaloids against bladder cancer.

Flavonoids induce cell death in Leishmania amazonensis: in vitro characterization by flow cytometry and Raman spectroscopy

Leishmaniasis comprises a group of infectious diseases with worldwide distribution, of which both the visceral and cutaneous forms are caused by Leishmania parasites. In the absence of vaccines, efficacious chemotherapy remains the basis for leishmaniasis control. The available drugs are expensive and associated with several secondary adverse effects. Due to these limitations, the development of new antileishmanial compounds is imperative, and plants offer various perspectives in this regard. The present study evaluated the in vitro leishmanicidal activity of flavonoids isolated from Solanum paludosum Moric. and investigated the mechanisms of cell death induced by them. These compounds were evaluated in vitro for their antileishmanial activity against Leishmania amazonensis promastigotes and they showed prominent leishmanicidal activity. The EtOAc fraction, gossypetin 3,7,8,4'-tetra-O-methyl ether (1), and kaempferol 3,7-di-O-methyl ether (3) were selected to be used in an in vitro assay against L. amazonensis amastigotes and cell death assays. The flavonoids (1) and (3) presented significant activity against L. amazonensis amastigotes, exhibiting the IC₅₀ values of 23.3 ± 4.5 μM, 34.0 ± 9.6 μM, and 10.5 ± 2.5 μM for the EtOAc fraction, (1), and (3), respectively, without toxic effects to the host cells. Moreover, (1) and (3) induced blocked cell cycle progression at the G1/S transition, ultimately leading to G1/G0 arrest. Flavonoid (3) also induced autophagy. Using Raman spectroscopy in conjunction with principal component analysis, the biochemical changes in the cellular components induced by flavonoids (1) and (3) were presented. The obtained results indicated that the mechanisms of action of (1) and (3) occurred through different routes. The results support that the flavonoids derived from S. paludosum can become lead molecules for the design of antileishmanial prototypes.

Effect of Thermal Processing on Antioxidant Activity and Cytotoxicity of Waste Potato Juice

Potato juice (PJ), commonly considered a burdensome waste, is rich in various compounds with bioactive properties. It has long been considered a remedy for gastric problems in traditional folk medicine. If valorization of PJ through implementation in the production of functional foods is to be considered, stabilization methods must be developed to allow long-term storage of this seasonal product. It is important that such methods are chosen with regard to their effect on the bioactive value of the obtained product. In this study, the impact of four stabilization methods on the antioxidant and cytotoxic activities of PJ was investigated. Elevated temperatures were used in thermal deproteinization used to obtain DPJW (deproteinated potato juice water) and spray-drying of FPJ (fresh potato juice) that resulted in SDPJ. Freeze drying and cryoconcentration were the low temperature processing methods that yielded PJL (potato juice lyophilisate) and CPJ (cryocorncentrated potato juice), respectively. All processed materials were characterized chemically and compared with raw materials in terms of phenolic compounds content, antioxidant activity as well as cytotoxicity to human tumor cells isolated from the gastric mucosa (Hs476T cell line), colon (Caco-2 and HT-29 cell lines), and normal cells isolated from the small intestine and colon epithelium (IEC-6 and NCM460 cell lines). It was stated that high-temperature processes – thermal deproteinization and spray-drying – yielded products with increased antioxidant potential (TEAC) that also showed increased cytotoxic activity towards intestinal cancer cells. At the same time the cytotoxicity towards normal cells remained on par with that of fresh PJ (IEC-6 cells) or decreased (NCM460 cells). Thermal deproteinization significantly decreased the content of glycoalcaloids in the juice, while spray drying did not have such an effect. The two low-temperature processes investigated – cryoconcentration and freeze drying – did not affect the PJ cytotoxic activity towards any of the cell lines used in the tests, whereas they did affect the antioxidant properties and glycoalcaloids content of PJ.

Solamargine inhibits proliferation and promotes apoptosis of CM-319 human chordoma cells through suppression of notch pathway

Background

Solamargine (SM), which represents a natural steroid alkaloid glycoside compound and a cytotoxic agent, has been proved to enhance the sensitivity of lung cancer cells to tumor necrosis factors (TNFs). In this study, we aimed to investigate the roles and mechanisms of SM in chordoma.

Methods

Cell viability, proliferation, apoptosis and cell cycle were measured by cell counting Kit-8 (CCK-8) assay, 5(6)-carboxyfluorescein diacetate succinimidyl ester (CFSE) labeling and flow cytometry (FCM), respectively. Western blot and quantitative real-time reverse transcription PCR (qRT-PCR) assays were performed to detect the expressions of related mRNAs and proteins.

Results

The results revealed that SM distinctly suppressed the proliferation of CM-319 cells. SM significantly induced the CM-319 cells apoptosis through up-regulating the expression levels of Caspase-3/8/9. The cell cycle of CM-319 cells was blocked by SM in G1 phase. Moreover, SM could significantly suppress the Notch pathway in CM-319 cells.

Conclusions

In conclusion, SM suppressed the proliferation and enhanced the apoptosis ability of CM-319 cells via suppressing the Notch pathway. The results suggested that SM might be a novel therapeutic agent and supported the utilization of SM in chordoma.

Fe3O4-solamargine induces apoptosis and inhibits metastasis of pancreatic cancer cells

Fe3O4-magnetic liposome (MLP) can deliver drugs to target tissues and can increase drug efficacy. The present study aimed to investigate the effects of solamargine (SM) and Fe3O4-SM in pancreatic cancer (PC). Cell viability was detected using a Cell Counting kit‑8 assay. Apoptosis and cell cycle progression was tested using a flow cytometry assay. A scratch assay was used to examine cell metastasis. Quantitative polymerase chain reaction, western blot analysis or immunohistochemical analysis were performed to determine the expression of target factors. Magnetic resonance imagining (MRI) and terminal deoxynucleotidyl-transferase-mediated dUTP nick end labelling were conducted to detect tumor growth and apoptosis in vivo, respectively. It was demonstrated that Fe3O4-SM inhibited cancer cell growth via a slow release of SM over an extended period of time. SM was revealed to induce apoptosis and cell cycle arrest. Furthermore, SM decreased the expression of X-linked inhibitor of apoptosis, Survivin, Ki‑67, proliferating cell nuclear antigen and cyclin D1, but increased the activity of caspase-3. It was also observed that SM inhibited tumor cell metastasis by modulating the expression of matrix metalloproteinase (MMP)-2 and TIMP metallopeptidase inhibitor-2. Furthermore, the phosphorylation of protein kinase B and mechanistic target of rapamycin was suppressed by SM. Notably, the effect of SM was enhanced by Fe3O4-SM. The malignant growth of PC was decreased by SM in vivo. Furthermore, the expression of Ki‑67 was decreased by SM and Fe3O4-SM. Additionally, cell apoptosis was increased in the Fe3O4-SM group, compared with the SM group. The present study illustrated the antitumor effect and action mec-hanism produced by SM. Additionally, it was demonstrated that Fe3O4-SM was more effective than SM in protecting against PC.

Steroidal glycoalkaloids from Solanum nigrum target cytoskeletal proteins: an in silico analysis

Background

Solanum nigrum (black nightshade; S. nigrum), a member of family Solanaceae, has been endowed with a heterogeneous array of secondary metabolites of which the steroidal glycoalkaloids (SGAs) and steroidal saponins (SS) have vast potential to serve as anticancer agents. Since there has been much controversy regarding safety of use of glycoalkaloids as anticancer agents, this area has remained more or less unexplored. Cytoskeletal proteins like actin play an important role in maintaining cell shape, synchronizing cell division, cell motility, etc. and along with their accessory proteins may also serve as important therapeutic targets for potential anticancer candidates. In the present study, glycoalkaloids and saponins from S. nigrum were screened for their interaction and binding affinity to cytoskeletal proteins, using molecular docking.

Methods

Bioactivity score and Prediction of Activity Spectra for Substances (PASS) analysis were performed using softwares Molinspiration and Osiris Data Explorer respectively, to assess the feasibility of selected phytoconstituents as potential drug candidates. The results were compared with two standard reference drugs doxorubicin hydrochloride (anticancer) and tetracycline (antibiotic). Multivariate data obtained were analyzed using principal component analysis (PCA).

Results

Docking analysis revealed that the binding affinities of the phytoconstituents towards the target cytoskeletal proteins decreased in the order coronin>villin>ezrin>vimentin>gelsolin>thymosin>cofilin. Glycoalkaloid solasonine displayed the greatest binding affinity towards the target proteins followed by alpha-solanine whereas amongst the saponins, nigrumnin-I showed maximum binding affinity. PASS Analysis of the selected phytoconstituents revealed 1 to 3 violations of Lipinski’s parameters indicating the need for modification of their structure-activity relationship (SAR) for improvement of their bioactivity and bioavailability. Glycoalkaloids and saponins all had bioactivity scores between −5.0 and 0.0 with respect to various receptor proteins and target enzymes. Solanidine, solasodine and solamargine had positive values of druglikeness which indicated that these compounds have the potential for development into future anticancer drugs. Toxicity potential evaluation revealed that glycoalkaloids and saponins had no toxicity, tumorigenicity or irritant effect(s). SAR analysis revealed that the number, type and location of sugar or the substitution of hydroxyl group on alkaloid backbone had an effect on the activity and that the presence of α-L-rhamnopyranose sugar at C-2 was critical for a compound to exhibit anticancer activity.

Conclusion

The present study revealed some cytoskeletal target(s) for S. nigrum phytoconstituents by docking analysis that have not been previously reported and thus warrant further investigations both in vitro and in vivo.

Sublethal Effects of Solanum nigrum Fruit Extract and Its Pure Glycoalkaloids on the Physiology of Tenebrio molitor (Mealworm)

BACKGROUND

Solanaceae plants produce glycoalkaloids (GAs) that affect various physiological processes of herbivorous insects and they are being tested as potential alternatives for synthetic pesticides. They cause lethal and sublethal effects. Nevertheless, their mode of action remains unclear. Therefore, we examined the effects of Solanum nigrum fruit extracts and pure glycoalkaloids on a model beetle, Tenebrio molitor.

METHODS

Plant extracts or pure alkaloids were added to the food of the larvae for three days. The lipid, glycogen, and protein content in the fat body and the midgut were determined, and the contractility of the heart, hindgut, and oviduct muscles was tested using the video-microscopy technique. Finally, the ultrastructure of the fat body and the midgut was observed using electron microscopy.

RESULTS

No lethal effects were noted. Sublethal changes were observed in the content of biomolecules, malformations of organelles, chromatin condensation, and heart and oviduct contractility. The observed effects differed between the tested glycoalkaloids and the extract.

CONCLUSIONS

Both the extract and pure GAs have a wide range of effects that may result in impaired development, food intake, and reproduction. Some early effects may be used as bioindicators of stress. The effects of the extract and pure alkaloids suggest that the substances produced by the plant may act additively or synergistically.

Synthesis of gold nanoparticles with Solanum xanthocarpum extract and their in vitro anticancer potential on nasopharyngeal carcinoma cells

BACKGROUND

Nasopharyngeal cancer (NPC) is one of the subtypes of head and neck cancers. It occurs rarely, and its prevalence depends mainly on geographical location. Modern-day research is focused on coupling nanotechnology and traditional medicine for combating cancers. Gold nanoparticles (AuNPs) were synthesized from Solanum xanthocarpum (Sx) leaf extract using reduction method.

METHODS

Characterization of the synthesized AuNPs was done by different techniques such as ultraviolet-visible spectrum absorption, X-ray diffraction, dynamic light scattering, Fourier transform infrared spectroscopy, transmission electron microscopy, and energy-dispersive X-ray analysis.

RESULTS

All the results showed the successful green synthesis of AuNPs from Sx, which induced apoptosis of C666-1 cell line (NPC cell line). There was a decline in both cell viability and colony formation in C666-1 cells upon treatment with Sx-AuNPs. The cell death was proved to be caused by autophagy and mitochondrial-dependent apoptotic pathway.

CONCLUSION

Thus, due to their anticancer potential, these nanoparticles coupled with Sx can be used for in vivo applications and clinical research in future.

Solamargine, a bioactive steroidal alkaloid isolated from Solanum aculeastrum induces non-selective cytotoxicity and P-glycoprotein inhibition

Background

Solanum aculeastrum fruits are used by some cancer sufferers as a form of alternative treatment. Scientific literature is scarce concerning its anticancer activity, and thus the aim of the study was to assess the in vitro anticancer and P-glycoprotein inhibitory potential of extracts of S. aculeastrum fruits. Furthermore, assessment of the combinational effect with doxorubicin was also done.

Methods

The crude extract was prepared by ultrasonic maceration. Liquid-liquid extraction yielded one aqueous and two organic fractions. Bioactive constituents were isolated from the aqueous fraction by means of column chromatography, solid phase extraction and preparative thin-layer chromatography. Confirmation of bioactive constituent identity was done by nuclear magnetic resonance and ultra-performance liquid chromatography mass spectrometry. The crude extract and fractions were assessed for cytotoxicity and P-glycoprotein inhibition in both cancerous and non-cancerous cell lines using the sulforhodamine B and rhodamine-123 assays, respectively.

Results

Both the crude extract and aqueous fraction was cytotoxic to all cell lines, with the SH-SY5Y neuroblastoma cell line being most susceptible to exposure (IC₅₀ = 10.72 μg/mL [crude], 17.21 μg/mL [aqueous]). Dose-dependent P-glycoprotein inhibition was observed for the crude extract (5.9 to 18.9-fold at 100 μg/mL) and aqueous fraction (2.9 to 21.2 at 100 μg/mL). The steroidal alkaloids solamargine and solanine were identified. While solanine was not bioactive, solamargine displayed an IC₅₀ of 15.62 μg/mL, and 9.1-fold P-glycoprotein inhibition at 100 μg/mL against the SH-SY5Y cell line. Additive effects were noted for combinations of doxorubicin against the SH-SY5Y cell line.

Conclusions

The crude extract and aqueous fraction displayed potent non-selective cytotoxicity and noteworthy P-glycoprotein inhibition. These effects were attributed to solamargine. P-glycoprotein inhibitory activity was only present at concentrations higher than those inducing cytotoxicity, and thus does not appear to be the likely mechanism for the enhancement of doxorubicin’s cytotoxicity. Preliminary results suggest that non-selective cytotoxicity may hinder drug development, however, further assessment of the mode of cell death is necessary to determine the route forward.

Bioactive steroidal alkaloids from the fruits of Solanum nigrum

The investigation of the fruits of Solanum nigrum led to the isolation of four previously undescribed steroidal alkaloids, named solanine A, 7α-OH khasianine, 7α-OH solamargine and 7α-OH solasonine, together with six known ones. The structures of the isolated compounds were elucidated unambiguously by spectroscopic data analyses and chemical methods. Solanine A represents an unusual steroidal alkaloid with an unprecedented 6/5/6/5/5/6 hexacyclic ring system, and its structure was confirmed by X-ray single crystal diffraction analysis. Compounds 2-4 were rare naturally occurring steroidal alkaloid glycosides bearing a hydroxyl group at C-7 position. Solanine A showed the most potent inhibitory activity against the LPS-induced NO production in murine RAW264.7 macrophages with an IC₅₀ value of 3.85 ± 0.71 μM and significant cytotoxicity against MGC803, HepG2 and SW480 cancer cell lines with IC₅₀ values of 6.00 ± 0.52 μM, 9.25 ± 0.49 μM and 6.23 ± 0.26 μM, respectively.

Solanum incanum extract (SR-T100) induces melanoma cell apoptosis and inhibits established lung metastasis

Melanoma, a cancer derived from melanocytes, is one of the most chemoresistant cancers and tends to metastasize. Once it metastasizes, the prognosis is poor. Even with the recent advancement of targeted therapy and immunotherapy, the prognosis remains discouraging. SR-T100, a Solanum incanum extract, shows anticancer effects against several cancers; however, its therapeutic efficacy against melanoma and established metastasis remains unknown. In this study, we showed that SR-T100 induces apoptosis, DNA damage, and G0/G1 cell cycle arrest in murine B16 melanoma cells in vitro. In vivo, intralesional injection of SR-T100 decreased the tumor size of the regional melanoma in the foot pad. Moreover, intraperitoneal injection of SR-T100 inhibited the growth and the number of established melanoma metastases in the lungs. Our study highlights SR-T100 as a potential novel treatment for established tumors from regional and metastatic melanoma.

Solasodine inhibits human colorectal cancer cells through suppression of the AKT/glycogen synthase kinase-3β/β-catenin pathway

Solasodine is a main active component isolated from Solanum incanum L. that performs a wide range of functions containing anti‐oxidant, anti‐infection, and neurogenesis promotion. In this study, we explored the influence of solasodine on three types of human colorectal cancer (CRC) cell lines. The results show that solasodine prohibited CRC cell proliferation dose‐ and time‐dependently and impeded CRC cell motility by downregulating MMPs. Solasodine was also found to fuel caspase‐cascade reaction and increase the ratio between Bax and Bcl‐2 so as to induce CRC cell apoptosis. When cells were pretreated with AKT activator (insulin‐like growth factor‐1) followed by solasodine, the solasodine‐induced apoptosis was partially abrogated by insulin‐like growth factor‐1. Moreover, solasodine hindered tumor development and stimulated similar mechanisms in vivo. In general, our study provides the first evidence that solasodine has a suppressive effect on CRC cells and that this agent may be a novel therapeutic drug for CRC treatment.

Non-edible parts of Solanum stramoniifolium Jacq. - a new potent source of bioactive extracts rich in phenolic compounds for functional foods

Extracts prepared from leaves, roots, and stems of Solanum stramoniifolium Jacq. (Solanaceae) in 80% ethanol have been tested for their in vitro antioxidant, anti-inflammatory, antimicrobial, and cytotoxic activities with an aim to find new sources of substances for functional foods and food additives. The root extract revealed the highest antioxidant activity in all assays exceeding the trolox capacity, and was the only extract that inhibited nitric oxide production in mouse macrophage cells, showing also the capacity to suppress the growth of all tested human tumor cell lines (MCF-7, NCI-H460, HeLa and HepG2). The leaf extract showed the strongest antimicrobial activity inhibiting all tested clinical isolates. To the author's best knowledge it was the first time that all individual parts of this plant were tested for biological activity together with the phenolic compound characterization.

Aglycone solanidine and solasodine derivatives: A natural approach towards cancer

Over the past few years, it was suggested that a rational approach to treat cancer in clinical settings requires a multipronged approach that augments improvement in systemic efficiency along with modification in cellular phenotype leads to more efficient cell death response. Recently, the combinatory delivery of traditional chemotherapeutic drugs with natural compounds proved to be astonishing to deal with a variety of cancers, especially that are resistant to chemotherapeutic drugs. The natural compounds not only synergize the effects of chemotherapeutics but also minimize drug associated systemic toxicity. In this review, our primary focus was on antitumor effects of natural compounds. Previously, the drugs from natural sources are highly precise and safer than drugs of synthetic origins. Many natural compounds exhibit anti-cancer potentials by inducing apoptosis in different tumor models, in-vitro and in-vivo. Furthermore, natural compounds are also found equally useful in chemotherapeutic drug resistant tumors. Moreover, these Phyto-compounds also possess numerous other pharmacological properties such as antifungal, antimicrobial, antiprotozoal, and hepatoprotection. Aglycone solasodine and solanidine derivatives are the utmost important steroidal glycoalkaloids that are present in various Solanum species, are discussed here. These natural compounds are highly cytotoxic against different tumor cell lines. As the molecular weight is concerned; these are smaller molecular weight chemotherapeutic agents that induce cell death response by initiating apoptosis through both extrinsic and intrinsic pathways.

Roots and Tuber Crops as Functional Foods: A Review on Phytochemical Constituents and Their Potential Health Benefits

Starchy roots and tuber crops play a pivotal role in the human diet. There are number of roots and tubers which make an extensive biodiversity even within the same geographical location. Thus, they add variety to the diet in addition to offering numerous desirable nutritional and health benefits such as antioxidative, hypoglycemic, hypocholesterolemic, antimicrobial, and immunomodulatory activities. A number of bioactive constituents such as phenolic compounds, saponins, bioactive proteins, glycoalkaloids, and phytic acids are responsible for the observed effects. Many starchy tuber crops, except the common potatoes, sweet potatoes, and cassava, are not yet fully explored for their nutritional and health benefits. In Asian countries, some edible tubers are also used as traditional medicinal. A variety of foods can be prepared using tubers and they may also be used in industrial applications. Processing may affect the bioactivities of constituent compounds. Tubers have an immense potential as functional foods and nutraceutical ingredients to be explored in disease risk reduction and wellness.

Solamargine triggers cellular necrosis selectively in different types of human melanoma cancer cells through extrinsic lysosomal mitochondrial death pathway

BACKGROUND

Previous reports showed that the Steroidal Glycoalkaloid Solamargine inhibited proliferation of non-melanoma skin cancer cells. However, Solamargine was not tested systematically on different types of melanoma cells and was not simultaneously tested on normal cells either. In this study we aimed to investigate the effect of Solamargine and the mechanism involved in inhibiting the growth of different types of melanoma cells.

METHODS

Solamargine effect was tested on normal cells and on another three melanoma cell lines. Vertical growth phase metastatic and primary melanoma cell lines WM239 and WM115, respectively and the radial growth phase benign melanoma cells WM35 were used. The half inhibitory concentration IC50 of Solamargine was determined using Alamarblue assay. The cellular and subcellular changes were assessed using light and Transmission Electron Microscope, respectively. The percentage of cells undergoing apoptosis and necrosis were measured using Flow cytometry. The different protein expression was detected and measured using western blotting. The efficacy of Solamargine was determined by performing the clonogenic assay. The data collected was analyzed statistically on the means of the triplicate of at least three independent repeated experiments using one-way ANOVA test for parametric data and Kruskal-Wallis for non-parametric data. Differences were considered significant when the P values were less than 0.05.

RESULTS

Hereby, we demonstrate that Solamargine rapidly, selectively and effectively inhibited the growth of metastatic and primary melanoma cells WM239 and WM115 respectively, with minimum effect on normal and benign WM35 cells. Solamargine caused cellular necrosis to the two malignant melanoma cell lines (WM115, WM239), by rapid induction of lysosomal membrane permeabilization as confirmed by cathepsin B upregulation which triggered the extrinsic mitochondrial death pathway represented by the release of cytochrome c and upregulation of TNFR1. Solamargine disrupted the intrinsic apoptosis pathway as revealed by the down regulation of hILP/XIAP, resulting in caspase-3 cleavage, upregulation of Bcl-xL, and Bcl2, and down regulation of Apaf-1 and Bax in WM115 and WM239 cells only. Solamargine showed high efficacy in vitro particularly against the vertical growth phase melanoma cells.

CONCLUSION

Our findings suggest that Solamargine is a promising anti-malignant melanoma drug which warrants further attention.

Bioactive Compounds Found in Brazilian Cerrado Fruits

Functional foods include any natural product that presents health-promoting effects, thereby reducing the risk of chronic diseases. Cerrado fruits are considered a source of bioactive substances, mainly phenolic compounds, making them important functional foods. Despite this, the losses of natural vegetation in the Cerrado are progressive. Hence, the knowledge propagation about the importance of the species found in Cerrado could contribute to the preservation of this biome. This review provides information about Cerrado fruits and highlights the structures and pharmacologic potential of functional compounds found in these fruits. Compounds detected in Caryocar brasiliense Camb. (pequi), Dipteryx alata Vog. (baru), Eugenia dysenterica DC. (cagaita), Eugenia uniflora L. (pitanga), Genipa americana L. (jenipapo), Hancornia speciosa Gomes (mangaba), Mauritia flexuosa L.f. (buriti), Myrciaria cauliflora (DC) Berg (jabuticaba), Psidiumguajava L. (goiaba), Psidium spp. (araçá), Solanum lycocarpum St. Hill (lobeira), Spondias mombin L. (cajá), Annona crassiflora Mart. (araticum), among others are reported here.

Solanum Incanum Extract Downregulates Aldehyde Dehydrogenase 1-Mediated Stemness and Inhibits Tumor Formation in Ovarian Cancer Cells

Solanum incanum extract (SR-T100), containing the active ingredient solamargine, can induce apoptosis via upregulation of tumor necrosis factor receptor expression and activation of the mitochondrial apoptosis pathway, and has therapeutic effects in patients with actinic keratosis. Here, we evaluate the novel molecular mechanisms underlying SR-T100-regulated stemness and chemoresistance. The concentration of SR-T100 that inhibited 50% cell viability (IC₅₀) was lower in ovarian cancer cells than in nonmalignant cells. Furthermore, the SR-T100 IC₅₀ in chemoresistant cells was similar to the IC₅₀ in chemosensitive cells. Additionally, SR-T100 increased cisplatin and paclitaxel sensitivity in chemoresistant cells. SR-T100 downregulated the expression of stem cell markers, including aldehyde dehydrogenase 1 (ALDH1), Notch1, and FoxM1, and reduced sphere formation in ovarian cancer cells. Using microarray analyses, immunoblotting, luciferase activity, and chromatin immunoprecipitation (ChIP) assays, we showed that SR-T100 suppressed the expression of c/EBPβ and COL11A1, and its promoter activity, in resistant cells, but not sensitive cells. SR-T100, paclitaxel, and cisplatin inhibited the growth of A2780CP70 cells in mouse xenografts, as compared to the vehicle control, and the combination of cisplatin and SR-T100 was more effective than either treatment alone. SR-T100 may represent a potential therapeutic adjunct to chemotherapy for ovarian cancer treatment.

Molecular docking study of natural alkaloids as multi-targeted hedgehog pathway inhibitors in cancer stem cell therapy

Cancer is responsible for millions of deaths throughout the world every year. Increased understanding as well as advancements in the therapeutic aspect seems suboptimal to restrict the huge deaths associated with cancer. The major cause responsible for this is high resistance as well as relapse rate associated with cancers. Several evidences indicated that cancer stem cells (CSC) are mainly responsible for the resistance and relapses associated with cancer. Furthermore, agents targeting a single protein seem to have higher chances of resistance than multitargeting drugs. According to the concept of network model, partial inhibition of multiple targets is more productive than single hit agents. Thus, by fusing both the premises that CSC and single hit anticancer drugs, both are responsible for cancer related resistances and screened alkaloids for the search of leads having CSC targeting ability as well as the capability to modulating multiple target proteins. The in silico experimental data indicated that emetine and cortistatin have the ability to modulate hedgehog (Hh) pathway by binding to sonic hedgehog (Hh), smoothened (Smo) and Gli protein, involved in maintenance CSCs. Furthermore, solamargine, solasonine and tylophorine are also seems to be good lead molecules targeting towards CSCs by modulating Hh pathway. Except solamargine and solasonine, other best lead molecules also showed acceptable in silico ADME profile. The predicted lead molecules can be suitably modified to get multitargeting CSC targeting agent to get rid of associate resistances.

Chemical synthesis of saponins

Saponins are a large family of amphiphilic glycosides of steroids and triterpenes found in plants and some marine organisms. By expressing a large diversity of structures on both sugar chains and aglycones, saponins exhibit a wide range of biological and pharmacological properties and serve as major active principles in folk medicines, especially in traditional Chinese medicines. Isolation of saponins from natural sources is usually a formidable task due to the microheterogeneity of saponins in Nature. Chemical synthesis can provide access to large amounts of natural saponins as well as congeners for understanding their structure-activity relationships and mechanisms of action. This article presents a comprehensive account on chemical synthesis of saponins. First highlighted are general considerations on saponin synthesis, including preparation of aglycones and carbohydrate building blocks, assembly strategies, and protecting-group strategies. Next described is the state of the art in the synthesis of each type of saponins, with an emphasis on those representative saponins having sophisticated structures and potent biological activities.

Pasta Fortified with Potato Juice: Structure, Quality, and Consumer Acceptance

The potential of potato juice in relieving gastrointestinal disorders has already been proven. Work continues on implementation of this active component into products that are widely consumed. In this article, results of an attempt to fortify pasta with potato juice are presented and discussed. Fortification is performed using fresh and dried juice. The influence of the addition on culinary properties of the final product, such as cooking weight and cooking loss, as well as microstructure, color, texture, and consumer acceptance were evaluated. It was found that potato juice can be used for fortification of pasta both in its fresh and dried forms, however the effects on different responses depend on the potato juice form used. The addition of potato juice influenced the color of the product reducing its lightness and shifting color balances from green to red, yellow color saturation was decreased as well. Changes in color were more significant in the case of fresh juice addition. The firmness and microstructure of pasta was also influenced. The surface microstructure of pasta containing fresh potato juice was different from that of the other 2 products being a likely explanation of the lower cooking loss observed in its case. In contrast, the consistency of dough was strengthened by addition of dried potato juice. Principal components analysis indicated that the color change had the most pronounced effect on consumer acceptance. Other physicochemical changes were slightly less significant. Nevertheless, sensory evaluation proved that functional pasta produced with fresh potato juice finds consumer acceptance comparable with that of classic pasta.

Chemistry and anticarcinogenic mechanisms of glycoalkaloids produced by eggplants, potatoes, and tomatoes

Inhibition of cancer can occur via apoptosis, a genetically directed process of cell self-destruction that involves numerous biomarkers and signaling pathways. Glycoalkaloids are nitrogen-containing secondary plant metabolites found in numerous Solanaceous plants including eggplants, potatoes, and tomatoes. Exposure of cancer cells to glycoalkaloids produced by eggplants (α-solamargine and α-solasonine), potatoes (α-chaconine and α-solanine), and tomatoes (α-tomatine) or their hydrolysis products (mono-, di-, and trisaccharide derivatives and the aglycones solasodine, solanidine, and tomatidine) inhibits the growth of the cells in culture (in vitro) as well as tumor growth in vivo. This overview comprehensively surveys and consolidates worldwide efforts to define the following aspects of these natural compounds: (a) their prevalence in the three foods; (b) their chemistry and structure-activity relationships; (c) the reported factors (biomarkers, signaling pathways) associated with apoptosis of bone, breast, cervical, colon, gastric, glioblastoma, leukemia, liver, lung, lymphoma, melanoma, pancreas, prostate, and squamous cell carcinoma cell lines in vitro and the in vivo inhibition of tumor formation and growth in fish and mice and in human skin cancers; and (d) future research needs. The described results may make it possible to better relate the structures of the active compounds to their health-promoting function, individually, in combination, and in food, and allow the consumer to select glycoalkaloid-containing food with the optimal content of nontoxic beneficial compounds. The described findings are expected to be a valuable record and resource for further investigation of the health benefits of food-related natural compounds.

α-Solanine inhibits invasion of human prostate cancer cell by suppressing epithelial-mesenchymal transition and MMPs expression

α-Solanine, a naturally occurring steroidal glycoalkaloid found in nightshade (Solanum nigrum Linn.), was found to inhibit proliferation and induce apoptosis of tumor cells. However, the mechanism involved in suppression of cancer cell metastasis by α-solanine remains unclear. This study investigates the suppression mechanism of α-solanine on motility of the human prostate cancer cell PC-3. Results show that α-solanine reduces the viability of PC-3 cells. When treated with non-toxic doses of α-solanine, cell invasion is markedly suppressed by α-solanine. α-Solanine also significantly elevates epithelial marker E-cadherin expression, while it concomitantly decreases mesenchymal marker vimentin expression, suggesting it suppresses epithelial-mesenchymal transition (EMT). α-Solanine reduces the mRNA level of matrix metalloproteinase-2 (MMP-2), MMP-9 and extracellular inducer of matrix metalloproteinase (EMMPRIN), but increases the expression of reversion-inducing cysteine-rich protein with kazal motifs (RECK), and tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2. Immunoblotting assays indicate α-solanine is effective in suppressing the phosphorylation of phosphatidylinositide-3 kinase (PI3K), Akt and ERK. Moreover, α-solanine downregulates oncogenic microRNA-21 (miR-21) and upregulates tumor suppressor miR-138 expression. Taken together, the results suggest that inhibition of PC-3 cell invasion by α-solanine may be, at least in part, through blocking EMT and MMPs expression. α-Solanine also reduces ERK and PI3K/Akt signaling pathways and regulates expression of miR-21 and miR-138. These findings suggest an attractive therapeutic potential of α-solanine for suppressing invasion of prostate cancer cell.

In vitro trypanocidal activity of solamargine and extracts from Solanum palinacanthum and Solanum lycocarpum of Brazilian cerrado

The present investigation was to evaluate the potential trypanocidal activity of crude ethanolic extract of the fruits of Solanum palinacanthum, Solanum lycocarpum and the glycoalcaloid, solamargine. S. palinacanthum and S. lycocarpum fruit powders were submitted to exhaustively extraction with 96% ethanol and solamargine were isolated from the extract of S. palinacanthum. Both extracts and solamargine were analysed for trypanocidal activity by using MTT colorimetric assay. Extracts of S. palinacanthum showed to be more active (IC50 = 175.9 µg.ml-1) than S. lycocarpum (IC50 = 194.7 µg.ml-1). Solamargine presented a strong activity (IC50 = 15.3 µg.ml-1), which can explain the better activity of the both extracts. Benznidazol (IC50 = 9.0 µg.ml-1) is the only drug used to treat Chagas' disease. These findings demonstrate for the first time that ethanol extracts obtained from both fruits of S. palinacanthum and S. lycocarpum and also solamargine have a potential anti-trypanosomal activity.

Characterization of Lycium barbarum polysaccharide and its effect on human hepatoma cells

To investigate structure-bioactivity relationship of LBP, Lycium barbarum polysaccharide (LBP) was extracted and separated into five fractions using ultrafiltration membrane method. Then the effects of these polysaccharide fractions on human liver cancer cells (SMMC-7721) were observed by MTT assay, LSCM and FCM. And the components, molecular weight and conformation of LBP fractions were analyzed by GC, HPLC and AFM. The results showed that LBP-a8, LBP-a3, LBP-a1 and LBP-a4 could inhibit the proliferation of SMMC-7721 cells in a concentration and time dependent manner. But LBP-p8 could promote the growth of SMMC-7721 cells. LBP-a4 (10.2 kDa), which consists of uronic acid (11.5%), protein (0.34%) and neutral sugar (39.02%), could arrest SMMC-7721 cells at G0/G1 phase and enhance the intracellular Ca(2+) concentration significantly. Nevertheless, LBP-p8 (6.50×10(3) kDa), which consists of uronic acid (13.4%), protein (4.77%) and neutral sugar (26.26%), did not change the cell cycle and Ca(2+) concentration in cytoplasm significantly. The molecular conformation of LBP-a4 and LBP-p8 was spherical and flocculent molecular shape, respectively, suggesting that spherical molecular shape was benefit to LBP's apoptosis inducing activity while flocculent molecular shape did not have that function.

Antiproliferative activity of Solanum lycocarpum alkaloidic extract and their constituents, solamargine and solasonine, in tumor cell lines

Natural products are some of the important sources of new anticancer drugs. The Brazilian flora is considered one of the most diverse in the word, although not many large-scale pharmacological and phytochemical studies have been conducted to date. With this in mind, in the present study we evaluated the antiproliferative activity of Solanum lycocarpum fruit glycoalkaloid extract (SL) and its major compounds, solamargine (SM) and solasonine (SS), against different tumor cell lines: murine melanoma (B16F10), human colon carcinoma (HT29), human breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), human hepatocellular liver carcinoma (HepG2) and human glioblastoma (MO59J, U343 and U251). The antiproliferative activity was evaluated using XTT assay and results were expressed as IC50. The most pronounced antiproliferative activity was observed for SM, with IC50 values ranging from 4.58 to 18.23 μg/mL. The lowest IC50 values were observed against HepG2, being 9.60 μg/mL for SL, 4.58 μg/mL for SM and 6.01 μg/mL for SS. Thus, SL, SM and SS demonstrated antiproliferative activity against the tumor cell lines tested, and were most effective against the HepG2 cell line.