Characterization of enantiomeric lignanamides from Solanum nigrum L. and their neuroprotective effects against MPP+-induced SH-SY5Y cells injury

Stereochemical insights into enantioselective antiplasmodial lignanamides from the twigs and leaves of Solanum erianthum

Stereochemical investigations on the twigs and leaves of Solanum erianthum afforded five pairs of lignanamide enantiomers and a previously undescribed phenolic amide (3). Particularly, two pairs of previously undescribed lignanamide racemates (1a/1b-2a/2b) represent the first case of natural products that feature an unreported 5/5-fused N/O-biheterocyclic core. Their structures, including the absolute configurations, were determined unambiguously by using spectroscopic analyses and electronic circular dichroism calculations. A speculative biogenetic pathway for 1-3 was proposed. Interestingly, these lignanamides exhibited enantioselective antiplasmodial activities against drug-sensitive Plasmodium falciparum 3D7 strain and chloroquine-resistant Plasmodium falciparum Dd2 strain, pointing out that chirality plays an important role in drug development.

Main chemical constituents and mechanism of anti-tumor action of Solanum nigrum L

OBJECTIVE

Solanum nigrum L. (SNL) is a natural drugwith diverse bioactive components and multi-targeted anti-tumor effects, gaining increasing attention in clinical application.

METHOD AND RESULTS

This paper reviews the studies on SNL by searching academic databases (Google Scholar, PubMed, Science Direct,and Web of Science, among others), analyzing its chemical compositions (alkaloids, saponins, polysaccharides, and polyphenols, among others), andbriefly describes the anti-tumor mechanisms of the main components.

DISCUSSION

This paper discusses the shortcomings of the current research on SNL and proposes corresponding solutions, providing theoretical support for further research on its biological functions and clinical efficacy.

Protective effect of phenylpropionamides in the seed of Cannabis Sativa L. on Parkinson's disease through autophagy

Parkinson's disease (PD) is the second most common neurodegenerative disease in the world. As one of the major degradation pathways, autophagy plays a pivotal role in maintaining the effective turnover of proteins and damaged organelles in cells. Lewy bodies composed of α-synuclein (α-syn) abnormally aggregated in the substantia nigra are important pathological features of PD, and autophagy dysfunction is considered to be an important factor leading to abnormal aggregation of α-syn. Phenylpropionamides (PHS) in the seed of Cannabis sativa L. have a protective effect on neuroinflammation and antioxidant activity. However, the therapeutic role of PHS in PD is unclear. In this study, the seeds of Cannabis sativa L. were extracted under reflux with 60% EtOH-H2O, and the 60% EtOH-H2O elution fraction was identified as PHS with the UPLC-QTOF-MS. The 1-methyl-4-phenyl-1,2,3,6-tetrahydro-pyridine (MPTP)-induced PD model in C57BL/6 J mice was used for behavioral and pharmacodynamic experiments. Behavioral symptoms were improved, Nissl-stained and TH-positive neurons in the substantia nigra were significantly increased in PHS-treated MPTP-induced PD model mice. Compared with the model group, PHS treatment reduced the expression level of α-syn, and the expression of TH increased significantly by western blotting, compared with the model group, the PHS group suppressed Caspase 3 and Bax expression and promoted Bcl-2 expression and levels of p62 decreased significantly, the ratio of LC3-II/I and p-mTOR/mTOR in the PHS group had a downward trend, suggesting that the therapeutic effect of PHS on MPTP-induced PD model mice may be triggered by the regulation of autophagy.

Structurally Diverse Phenylpropanamides from Cannabis Fructus and Their Potential Neuroprotective Effects

This study aimed to investigate the chemical components and potential health benefits of the fruits of Cannabis sativa L. Fourteen new phenylpropanamides designated as cannabisin I-XIV (1-14) and 40 known analogs were isolated and characterized via nuclear magnetic resonance spectroscopy, high-resolution electrospray ionization mass spectrometry, and electronic circular dichroism. In vitro bioassay using H2O2-induced PC12 cell damage models demonstrated that hempseeds extract and compounds 1, 3, 15, 26, 30, 36, 41, and 48 exhibited neuroprotective properties. 3,3'-Demethylgrossamide (30) displayed encouraging protection activity, which was further investigated to relieve the oxidative stress and apoptosis of PC12 cells treated with H2O2. The isolation and characterization of these neuroprotective phenylpropanamides from the fruits of C. sativa provide insights into its health-promoting properties as a healthy food and herbal medicine for preventing and treating neurodegenerative diseases, especially Alzheimer's disease.

Stereochemical insights into structurally diverse lignanamides from the herbs of Solanum lyratum Thunb

A chemical investigation of Solanum lyratum Thunb. (Solanaceae) afforded six pairs of enantiomeric lignanamides consisting of twelve undescribed compounds, along with two undescribed racemic mixtures, and the separations of the enantiomers were accomplished by chiral-phase HPLC. The structures of these undescribed compounds were elucidated by the analysis of spectroscopic data, NMR and electronic circular dichroism calculations. All isolated compounds were assessed for neuroprotective activities in H2O2-induced human neuroblastoma SH-SY5Y cells, and acetylcholinesterase (AChE) inhibitory activities. Among tested isolates, some enantiomeric lignanamides exhibited conspicuous neuroprotective effects and AChE inhibitory effect.

Rapid determination of the relative configuration of diverse 8,4'-oxyneolignans by NMR analysis: Retrospective studies, improvement and structural revision

The characteristic 1H NMR signals (H-7 and H2-9) are significant parameters that have been widely used to assess the relative configuration of H-7 and H-8 of 8,4'-oxyneolignans. However, many usual 8,4'-oxyneolignans cannot be accurately determined by existing NMR methods and no research considering their limitations was performed until now. In this study, the application scope of NMR methods was comprehensively studied and the ΔδH9a-H9b methods have been extended to solve the majority of configuration determination difficulties. The accuracy of extended NMR methods was verified by anisotropic NMR (RCSA measurements), NMR calculation and diverse statistical analysis (MAEΔΔδ, CP3 and DP4+). Furthermore, the theoretical conformational analysis was performed to investigate the inherent limitations of existing NMR methods. This study could provide a valuable reference for determining the relative configuration of H-7 and H-8 in 8,4'-oxyneolignans and the relative configuration of 23 recently reported 8,4'-oxyneolignan derivatives should be reassigned as well.

Four Pairs of Neuroprotective Aryldihydronaphthalene-Type Lignanamide Enantiomers from the Herbs of Solanum lyratum

Four pairs of aryldihydronaphthalene-type lignanamide enantiomers were isolated from Solanum lyratum (Solanaceae). The enantiomeric separation was accomplished by chiral-phase HPLC, and five undescribed compounds were elucidated. Analysis by various spectroscopy and ECD calculations, the structures of undescribed compounds were illuminated. The neuroprotective effects of all compounds were evaluated using H2 O2 -induced human neuroblastoma SH-SY5Y cells and AchE inhibition activity. Among them, compound 4 a exhibited remarkable neuroprotective effects at high concentrations of 25 and 50 μmol/L comparable to Trolox. Compound 1 a showed the highest AchE inhibition with the IC50 value of 3.06±2.40 μmol/L. Molecular docking of the three active compounds was performed and the linkage between the compounds and the active site of AchE was elucidated.

Mining the chemical diversity of the hemp seed (Cannabis sativa L.) metabolome: discovery of a new molecular family widely distributed across hemp

Hemp (Cannabis sativa L.) is a widely researched industrial crop with a variety of applications in the pharmaceutical, nutraceutical, food, cosmetic, textile, and materials industries. Although many of these applications are related to its chemical composition, the chemical diversity of the hemp metabolome has not been explored in detail and new metabolites with unknown properties are likely to be discovered. In the current study, we explored the chemical diversity of the hemp seed metabolome through an untargeted metabolomic study of 52 germplasm accessions to 1) identify new metabolites and 2) link the presence of biologically important molecules to specific accessions on which to focus on in future studies. Multivariate analysis of mass spectral data demonstrated large variability of the polar chemistry profile between accessions. Five main groups were annotated based on their similar metabolic fingerprints. The investigation also led to the discovery of a new compound and four structural analogues, belonging to a previously unknown chemical class in hemp seeds: cinnamic acid glycosyl sulphates. Although variability in the fatty acid profiles was not as marked as the polar components, some accessions had a higher yield of fatty acids, and variation in the ratio of linoleic acid to α-linolenic acid was also observed, with some varieties closer to 3:1 (reported as optimal for human nutrition). We found that that cinnamic acid amides and lignanamides, the main chemical classes of bioactive metabolites in hemp seed, were more concentrated in the Spanish accession Kongo Hanf (CAN58) and the French accession CAN37, while the Italian cultivar Eletta Campana (CAN48) demonstrated the greatest yield of fatty acids. Our results indicate that the high variability of bioactive and novel metabolites across the studied hemp seed accessions may influence claims associated with their commercialization and inform breeding programs in cultivar development.

Structurally Diverse Phenolic Amides from the Fruits of Lycium barbarum with Potent α-Glucosidase, Dipeptidyl Peptidase-4 Inhibitory, and PPAR-γ Agonistic Activities

A total of nine new phenolic amides (1-9), including four pairs of enantiomeric mixtures (3-5 and 8), along with ten known analogues (10-19) were identified from the fruits of Lycium barbarum using bioassay-guided chromatographic fractionation. Their structures were elucidated by comprehensive spectroscopic and spectrometric analyses, chiral HPLC analyses, and quantum NMR, and electronic circular dichroism calculations. Compounds 5-7 are the first example of feruloyl tyramine dimers fused through a cyclobutane ring. The activity results indicated that compounds 1, 11, and 13-17 exhibited remarkable inhibition against α-glucosidase with IC₅₀ of 1.11-33.53 μM, 5-150 times stronger than acarbose (IC₅₀ = 169.78 μM). Meanwhile, compounds 4a, 4b, 5a, 5b, 13, and 14 exerted moderate agonistic activities for peroxisome proliferator-activated receptor (PPAR-γ), with EC₅₀ values of 10.09-44.26 μM. Especially,compound 14 also presented inhibitory activity on dipeptidyl peptidase-4 (DPPIV), with an IC₅₀ value of 47.13 μM. Furthermore, the banding manner of compounds 14 and 17 with the active site of α-glucosidase, DPPIV, and PPAR-γ was explored by employing molecular docking analysis.

Anti-inflammatory steroids from the stems of Solanum nigrum L

Sixteen previously undescribed steroidal sapogenins along with two known ones were isolated from the stems of Solanum nigrum L. (Solanaceae). Their structures were identified using a combination of 1D and 2D NMR, HR-ESI-MS spectroscopy, the Mosher method, and X-ray diffraction analysis. Compounds 1-8 have an unusual F ring and 9-12 have a derived A ring, both of which are rare skeletons found in natural products. The biological evaluation showed that the isolated steroids exhibited inhibition of nitric oxide in the LPS-induced RAW 264.7 macrophages with IC₅₀ values from 7.4 to 41.3 μM. Further studies revealed that compounds 6 and 10 exhibited anti-inflammatory activity by blocking the nuclear translocation of NF-κB, and down-regulating the expression of iNOS, COX-2, IL-1β, and IL-6 in a concentration-dependent manner. These results suggest that the stems of S. nigrum may serve as a source of anti-inflammatory agents for use in healthy or medicinal products.

Colorimetric and antioxidant films based on biodegradable polymers and black nightshade (Solanum nigrum L.) extract for visually monitoring Cyclina sinensis freshness

In this study, colorimetric and antioxidant films were developed by using cassava starch (CS), κ-carrageenan (KC) and black nightshade fruit anthocyanins (BNA), and their physical and functional properties were investigated. We found BNA presented significant color changes in different pH solutions. And incorporation of BNA significantly increased the tensile strength, water vapor permeability, UV-vis light barrier property, pH-sensitivity and antioxidant activity of CS-KC film. Results of structural characterization indicated that H-bonds were formed between CS, KC and BNA in films and the film compactness was significantly improved by BNA incorporation. Results of the rheological property assay showed the films had high apparent viscosity with an obvious shear-thinning behavior. When applied to monitoring the quality change of Cyclina sinensis, CS-KC-BNA films exhibited significant color changes with the degradation process of C. sinensis qualities. Our results suggested CS-KC-BNA films could be utilized in smart packaging in food industry.

Phytochemistry and Pharmacology of Medicinal Plants Used by the Tenggerese Society in Java Island of Indonesia

The archipelagic country of Indonesia is inhabited by 300 ethnic groups, including the indigenous people of Tengger. Based on the reported list of medicinal plants used by the Tengger community, we have reviewed each of them for their phytochemical constituents and pharmacological activities. Out of a total of 41 medicinal plants used by the Tengerrese people, 33 species were studied for their phytochemical and pharmacological properties. More than 554 phytochemicals with diverse molecular structures belonging to different chemical classes including flavonoids, terpenoids, saponins and volatiles were identified from these studied 34 medicinal plants. Many of these medicinal plants and their compounds have been tested for various pharmacological activities including anti-inflammatory, antimicrobial, wound healing, headache, antimalarial and hypertension. Five popularly used medicinal plants by the healers were Garcinia mangostana, Apium graveolens, Cayratia clematidea, Drymocallis arguta and Elaeocarpus longifolius. Only A. graviolens were previously studied, with the outcomes supporting the pharmacological claims to treat hypertension. Few unexplored medicinal plants are Physalis lagascae, Piper amplum, Rosa tomentosa and Tagetes tenuifolia, and they present great potential for biodiscovery and drug lead identification.

Solanum nigrum Linn.: An Insight into Current Research on Traditional Uses, Phytochemistry, and Pharmacology

Solanum nigrum Linn., is a common edible medicinal herb of the Solanaceae family which is native to Southeast Asia and is now widely distributed in temperate to tropical regions of Europe, Asia, and America. Traditionally, it has been used to treat various cancers, acute nephritis, urethritis, leucorrhea, sore throat, toothache, dermatitis, eczema, carbuncles, and furuncles. Up to now, 188 chemical constituents have been identified from S. nigrum. Among them, steroidal saponins, alkaloids, phenols, and polysaccharides are the major bioactive constituents. Investigations of pharmacological activities of S. nigrum revealed that this edible medicinal herb exhibits a wide range of therapeutic potential, including antitumor, anti-inflammatory, antioxidant, antibacterial, and neuroprotective activities both in vivo and in vitro. This article presents a comprehensive and systematic overview of the botanical, traditional uses, phytochemical compositions, pharmacological properties, clinical trials, and toxicity of S. nigrum to provide the latest information for further exploitation and applications of S. nigrum in functional foods and medicines.

Lignanamides from the roots of Limonium gmelinii (Willd.) Kuntze and their anti-diabetic, cytotoxic and anti-inflammatory activities

Nine undescribed lignanamides, limoniumins A-I, together with ten known lignanamides and two known phenolics were isolated from ethyl acetate extract of the roots of Limonium gmelinii (Plumbaginaceae). Their structures were determined by spectroscopic analysis including 1D and 2D NMR and HRESIMS experiments. Limoniumin A is the first hybrid lignanamide of phenylpropanoid and coumarin. All tested lignanamides showed significant inhibitory activity against α-glucosidase stronger than positive control and remarkable inhibitory effect to PTP1B with IC₅₀ values less than 10 μM. In addition, some lignanamides exhibited moderate cytotoxic activity against HeLa and MCF-7 cells and anti-inflammatory activity against COX-2 in a dose-dependent way.

Lignanamides: sources, biosynthesis and potential health benefits - a minireview

Lignanamides are natural plant secondary metabolites derived from oxidative coupling mechanism with hydroxycinnamic acid amides as intermediates. These compounds display powerful anti-inflammatory, antioxidant, anti-cancer and anti-hyperlipidemic capacities in vitro, cell culture and in vivo studies. With strong potential to be utilized as protective agents against human chronic diseases, these compounds have attracted the interest of researchers. This review aims to discuss current understanding on the sources, classification, biosynthesis of lignanamides in plants, and importantly their biological activity and potential health benefits. The general biosynthesis pathway for lignanamides is comprehensively summarized, though some details in molecular regulation of the coupling process have yet to be elucidated. Lignanamides deserves additional clinical studies involving animal and human subjects, to prove its health benefits.

Hempseed Lignanamides Rich-Fraction: Chemical Investigation and Cytotoxicity towards U-87 Glioblastoma Cells

The weak but noteworthy presence of (poly)phenols in hemp seeds has been long overshadowed by the essential polyunsaturated fatty acids and digestible proteins, considered responsible for their high nutritional benefits. Instead, lignanamides and their biosynthetic precursors, phenylamides, seem to display interesting and diverse biological activities only partially clarified in the last decades. Herein, negative mode HR-MS/MS techniques were applied to the chemical investigation of a (poly)phenol-rich fraction, obtained from hemp seeds after extraction/fractionation steps. This extract contained phenylpropanoid amides and their random oxidative coupling derivatives, lignanamides, which were the most abundant compounds and showed a high chemical diversity, deeply unraveled through high resolution tandem mass spectrometry (HR-MS/MS) tools. The effect of different doses of the lignanamides-rich extract (LnHS) on U-87 glioblastoma cell line and non-tumorigenic human fibroblasts was evaluated. Thus, cell proliferation, genomic DNA damage, colony forming and wound repair capabilities were assessed, as well as LnHS outcome on the expression levels of pro-inflammatory cytokines. LnHS significantly inhibited U-87 cancer cell proliferation, but not that of fibroblasts, and was able to reduce U-87 cell migration, inducing further DNA damage. No modification in cytokines' expression level was found. Data acquired suggested that LnHS acted in U-87 cells by inducing the apoptosis machinery and suppressing the autophagic cell death.