PTP1B inhibition studies of biological active phloroglucinols from the rhizomes of Dryopteris crassirhizoma: Kinetic properties and molecular docking simulation

Insights into Chemical Diversity and Potential Health-Promoting Effects of Ferns

The scientific community is focusing on how to enhance human health and immunity through functional foods, and dietary supplements are proven to have a positive as well as a protective effect against infectious and chronic diseases. Ferns act as a taxonomical linkage between higher and lower plants and are endowed with a wide chemical diversity not subjected to sufficient scrutinization before. Even though a wealth of traditional medicinal fern uses were recorded in Chinese medicine, robust phytochemical and biological investigations of these plants are lacking. Herein, an extensive search was conducted using the keywords ferns and compounds, ferns and NMR, ferns and toxicity, and the terms ferns and chemistry, lignans, Polypodiaceae, NMR, isolation, bioactive compounds, terpenes, phenolics, phloroglucinols, monoterpenes, alkaloids, phenolics, and fatty acids were utilized with the Boolean operators AND, OR, and NOT. Databases such as PubMed, Web of Science, Science Direct, Scopus, Google Scholar, and Reaxys were utilized to reveal a wealth of information regarding fern chemistry and their health-promoting effects. Terpenes followed by phenolics represented the largest number of isolated active compounds. Regarding the neuroprotective effects, Psilotium, Polypodium, and Dryopteris species possessed as their major phenolics component unique chemical moieties including catechins, procyanidins, and bioflavonoids. In this updated chemical review, the pharmacological and chemical aspects of ferns are compiled manifesting their chemical diversity in the last seven years (2017-2024) together with a special focus on their nutritive and potential health-promoting effects.

Protein tyrosine phosphatase 1B in metabolic and cardiovascular diseases: from mechanisms to therapeutics

Protein Tyrosine Phosphatase 1B (PTP1B) has emerged as a significant regulator of metabolic and cardiovascular disease. It is a non-transmembrane protein tyrosine phosphatase that negatively regulates multiple signaling pathways integral to the regulation of growth, survival, and differentiation of cells, including leptin and insulin signaling, which are critical for development of obesity, insulin resistance, type 2 diabetes, and cardiovascular disease. Given PTP1B's central role in glucose homeostasis, energy balance, and vascular function, targeted inhibition of PTP1B represents a promising strategy for treating these diseases. However, challenges, such as off-target effects, necessitate a focus on tissue-specific approaches, to maximize therapeutic benefits while minimizing adverse outcomes. In this review, we discuss molecular mechanisms by which PTP1B influences metabolic and cardiovascular functions, summarize the latest research on tissue-specific roles of PTP1B, and discuss the potential for PTP1B inhibitors as future therapeutic agents.

Dryopteris crassirhizoma Nakai.: A review of its botany, traditional use, phytochemistry, pharmacological activity, toxicology and pharmacokinetics

ETHNOPHARMACOLOGICAL RELEVANCE

The Dryopteris crassirhizoma Nakai., a commonly used herb, is known as "Guan Zhong" in China, "Oshida" in Japan and "Gwanjung" in Korea. It has long been used for parasitic infestation, hemorrhages and epidemic influenza.

AIM OF THE REVIEW

The present paper aims to provide an up-to-date review at the advancements of the investigations on the traditional use, phytochemistry, pharmacological activity, toxicology and pharmacokinetics of D. crassirhizoma. Besides, possible trends, therapeutic potentials, and perspectives for future research of this plant are also briefly discussed.

MATERIALS AND METHODS

Relevant information on traditional use, phytochemistry, pharmacological activity, toxicology and pharmacokinetics of D. crassirhizoma was collected through published materials and electronic databases, including the Chinese Pharmacopoeia, Flora of China, Web of Science, PubMed, Baidu Scholar, Google Scholar, and China National Knowledge Infrastructure. 109 papers included in the article and we determined that no major information was missing after many checks. All authors participated in the review process for this article and all research paper are from authoritative published materials and electronic databases.

RESULTS

130 chemical components, among which phloroglucinols are the predominant groups, have been isolated and identified from D. crassirhizoma. D. crassirhizoma with its bioactive compounds is possessed of extensive biological activities, including anti-parasite, anti-microbial, anti-viral, anti-cancer, anti-inflammatory, anti-oxidant, anti-diabetic, bone protective, immunomodulatory, anti-platelet and anti-hyperuricemia activity. Besides, D. crassirhizoma has special toxicology and pharmacokinetics characterization.

CONCLUSIONS

D. crassirhizoma is a traditional Chinese medicine having a long history of application. This review mainly summarized the different chemical components extract from D. crassirhizoma and various reported pharmacological effects. Besides, the toxicology and pharmacokinetics of D. crassirhizoma also be analysed in this review. However, the chemical components of D. crassirhizoma are understudied and require further research to expand its medicinal potential, and it is urgent to design a new extraction scheme, so that the active ingredients can be obtained at a lower cost.

Acetylcholinesterase inhibition studies of alkaloid components from Crinum asiaticum var. sinicum: in vitro assessments by molecular docking and molecular dynamics simulations

Alkaloids are among the most important and best-known secondary metabolites as sources of new drugs from medicinal plants and marine organisms. A phytochemical investigation of the whole plant of Crinum asiaticum var. sinicum resulted in the isolation of seven alkaloids (1-7), including one new dimeric compound, bis-(-)-8-demethylmaritidine (1). Their structures were elucidated using NMR and HR-ESI-MS. The absolute configuration of new compound 1 was established by circular dichroism spectroscopy. All isolated compounds were evaluated for their inhibitory effects on acetylcholinesterase (AChE) activity in vitro. Among them, compound 1 exhibited the most potent AChE inhibition. Moreover, molecular docking and molecular dynamics simulations were carried out for the most active compound to investigate their binding interactions and dynamics behavior of the AChE protein-ligand complex. Therefore, compound 1 may be a potential candidate for effectively treating Alzheimer's disease.

Optimization of Ultrasonic-Assisted Extraction of α-Glucosidase Inhibitors from Dryopteris crassirhizoma Using Artificial Neural Network and Response Surface Methodology

Dryopteris crassirhizoma Nakai is a plant with significant medicinal properties, such as anticancer, antioxidant, and anti-inflammatory activities, making it an attractive research target. Our study describes the isolation of major metabolites from D. crassirhizoma, and their inhibitory activities on α-glucosidase were evaluated for the first time. The results revealed that nortrisflavaspidic acid ABB (2) is the most potent α-glucosidase inhibitor, with an IC₅₀ of 34.0 ± 0.14 μM. In addition, artificial neural network (ANN) and response surface methodology (RSM) were used in this study to optimize the extraction conditions and evaluate the independent and interactive effects of ultrasonic-assisted extraction parameters. The optimal extraction conditions are extraction time of 103.03 min, sonication power of 342.69 W, and solvent-to-material ratio of 94.00 mL/g. The agreement between the predicted models of ANN and RSM and the experimental values was notably high, with a percentage of 97.51% and 97.15%, respectively, indicating that both models have the potential to be utilized for optimizing the industrial extraction process of active metabolites from D. crassirhizoma. Our results could provide relevant information for producing high-quality extracts from D. crassirhizoma for functional foods, nutraceuticals, and pharmaceutical industries.

Undescribed phloroglucinol derivatives with antiviral activities from Dryopteris atrata (Wall. Ex Kunze) Ching

Nine undescribed phloroglucinol derivatives (dryatraols A-I) with five different backbones and three known dimeric acylphloroglucinols were isolated from the rhizome of Dryopteris atrata (Wall. Ex Kunze) Ching (Dryopteridaceae). Dryatraol A contains an unprecedented carbon skeleton-a butyrylphloroglucinol and a rulepidanol-type sesquiterpene are linked via a furan ring to form a 6/5/6/6 ring system. Dryatraols B and C are the first examples of monomeric phloroglucinols coupled with the aristolane-type sesquiterpene through the C-C bond. Dryatraol D features a rare spiro [benzofuran-2',5″-furan] backbone. Dryatraols E-I are five undescribed adducts with a butyrylphloroglucinol or filicinic acid incorporated into the germacrene-type sesquiterpene via a pyran ring. These undescribed structures were determined by comprehensively analysing the spectroscopic data, X-ray diffraction results, and electronic circular dichroism calculations. The result of in vitro antiviral activity evaluation indicated that dryatraol C displayed the strongest antiviral effect against both respiratory syncytial virus and influenza A virus (H1N1), with IC₅₀ values of 11.9 μM and 5.5 μM, respectively. Dryatraols F-H exhibited considerable inhibitory activity against herpes simplex virus type 1 (HSV-1), with IC₅₀ values ranging from 2.6 to 6.3 μM. Analysis of the inhibitory mechanism using a time-of-addition assay revealed that dryatraol G may inhibit the replication of HSV-1 by interfering with the late stage of the viral life cycle.

Spectroscopic analysis, kinetic mechanism, computational docking, and molecular dynamics of active metabolites from the aerial parts of Astragalus membranaceusBunge as tyrosinase inhibitors

A new isoflavane derivative (2), a new natural isoflavane (6), four new oleanane-type triterpenoid saponins (23, 25, 28, and 29), and twenty three known secondary metabolites (1, 3-5, 7-22, 24, 26, and 27) were isolated from the aerial parts of Astragalus membranaceus Bunge. The chemical structures of these compounds were elucidated through spectroscopic analysis and compared with those identified in previous studies. Tyrosinase inhibition ability of isolated compounds (1-29) was evaluated. Of these, compounds 3, 4, 6, and 14 exhibited inhibitory effects, with IC₅₀ values ranging from 24.6 to 59.2 μM. According to kinetic analysis, compounds 3 and 4 were non-competitive inhibitors of tyrosinase, whereas compounds 6 and 14 inhibited tyrosinase in uncompetitive and competitive modes, respectively. Molecular docking analysis identified that compounds 3, 4, and 6 could bind to allosteric sites and compound 14 could bind to the catalytic site of tyrosinase, which is consistent with the results of kinetic studies. Molecular dynamics behaviors of the active compounds in complex with tyrosinase were investigated via 60 ns simulation which demonstrated their high stability. These findings indicate that the aerial parts of A. membranaceus are a potential source of natural tyrosinase inhibitors.

Toxicity Effects of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) on Two Green Microalgae Species

Amongst per- and polyfluoroalkyl substances (PFAS) compounds, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have a high persistence in physicochemical and biological degradation; therefore, the accumulation of PFOS and PFOA can negatively affect aquatic organisms and human health. In this study, two microalgae species (Chlorella vulgaris and Scenedesmus obliquus) were exposed to different concentrations of a PFOS and PFOA mixture (0 to 10 mg L^-1). With increases in the contact time (days) and the PFAS concentration (mg L^-1) from 1 to 7, and 0.5 to 10, respectively, the cell viability, total chlorophyll content, and protein content decreased, and the decrease in these parameters was significantly greater in Scenedesmus obliquus. As another step in the study, the response surface methodology (RSM) was used to optimize the toxicity effects of PFAS on microalgae in a logical way, as demonstrated by the high R² (>0.9). In another stage, a molecular docking study was performed to monitor the interaction of PFOS and PFOA with the microalgae, considering hydrolysis and the enzymes involved in oxidation-reduction reactions using individual enzymes. The analysis was conducted on carboxypeptidase in Chlorella vulgaris and on c-terminal processing protease and oxidized cytochrome c6 in Scenedesmus obliquus. For the enzyme activity, the affinity and dimensions of ligands-binding sites and ligand-binding energy were estimated in each case.

Status of research on natural protein tyrosine phosphatase 1B inhibitors as potential antidiabetic agents: Update

Protein tyrosine phosphatase 1B (PTP1B) is a crucial therapeutic target for multiple human diseases comprising type 2 diabetes (T2DM) and obesity because it is a seminal part of a negative regulator in both insulin and leptin signaling pathways. PTP1B inhibitors increase insulin receptor sensitivity and have the ability to cure insulin resistance-related diseases. However, the few PTP1B inhibitors that entered the clinic (Ertiprotafib, ISIS-113715, Trodusquemine, and JTT-551) were discontinued due to side effects or low selectivity. Molecules with broad chemical diversity extracted from natural products have been reported to be potent PTP1B inhibitors with few side effects. This article summarizes the recent PTP1B inhibitors extracted from natural products, clarifying the current research progress, and providing new options for designing new and effective PTP1B inhibitors.

Selective Inhibition of PTP1B by New Anthraquinone Glycosides from Knoxia valerianoides

Protein tyrosine phosphatase 1B (PTP1B) is highly validated as a therapeutic target for type 2 diabetes. However, active site-directed PTP1B inhibitors generally suffer from poor selectivity and bioavailability. Inspired by the identification of a unique anthraquinone-coumarin hybrid from Knoxia valerianoides exhibiting good specificity for PTP1B over the highly homologous T-cell protein tyrosine phosphatase (TCPTP), further chemical investigation of this plant species led to the isolation of nine new anthraquinone glycosides (1-9) and two known ones (10 and 11). Structures were characterized by a combination of spectroscopic analyses and chemical methods. All compounds showed PTP1B inhibitory activities with IC₅₀ values ranging from 1.05 to 13.74 μM. Compounds 4 and 8 exhibited greater than 64-fold selectivity over TCPTP. Enzyme kinetic studies revealed that compounds 4 and 7 behaved as mixed-type inhibitors. Docking studies predicted similar binding modes of these compounds at the allosteric site positioned between helices α3 and α6.

Inhibitory Activity of Bioactive Phloroglucinols from the Rhizomes of Dryopteris crassirhizoma on Escherichia coli β-Glucuronidase: Kinetic Analysis and Molecular Docking Studies

Phloroglucinols-one of the major secondary metabolites in Dryopteris crassirhizoma-exhibit various pharmacological effects, such as antiviral, antioxidant, and antidiabetic activities. This study evaluated 30 phloroglucinols isolated from the rhizomes of D. crassirhizoma for their inhibitory activity on β-glucuronidase via in vitro assays. Among them, dimeric phloroglucinols 13-15 moderately inhibited β-glucuronidase, and trimeric phloroglucinols 26-28 showed strong inhibitory effects, with IC₅₀ values ranging from 5.6 to 8.0 μM. Enzyme kinetic analysis confirmed all six active compounds to be in a competitive mode of inhibition. Molecular docking simulations revealed the key binding interactions with the active site of β-glucuronidase protein and the binding mechanisms of these active metabolites. Our results suggest that the rhizomes of D. crassirhizoma and trimeric compounds 26-28 may serve as potential candidates for discovering and developing new β-glucuronidase inhibitors.

Anti-inflammatory activity and cytotoxicity against ovarian cancer cell lines by amide alkaloids and piperic esters isolated from Piper longum fruits: In vitro assessments and molecular docking simulation

Three new amide alkaloids, piperlongumamides D-F (14, 19, and 32); a new piperic ester, piperlongumester A (45); and two new natural compounds, methyl (2E,4Z)-5-(1,3-benzodioxol-5-yl)penta-2,4-dienoate (46) and trans-piperolein B ester (47), along with 41 known compounds were isolated from the fruits of Piper longum L. Their structures were identified by analyzing spectroscopic data, including mass spectrometry, 1D, and 2D NMR data. The anti-inflammatory and cytotoxic activities of all isolated compounds (1-47) were evaluated. Compounds 3, 6, and 19 inhibited nitric oxide production with IC₅₀ values of 16.1 ± 0.94, 14.5 ± 0.57, and 27.3 ± 1.11 μM, respectively, whereas compound 1 exhibited strong cytotoxic activity toward three ovarian cancer cell lines A2780, TOV-112D, and SK-OV3, with IC₅₀ values of 6.7 ± 0.77, 5.8 ± 0.29, and 48.3 ± 0.40 μM, respectively. Molecular docking simulations were performed to identify the interaction and binding mechanisms of these active metabolites with proteins related to inflammation and cancer.

Steroid glycosides isolated from Paris polyphylla var. chinensis aerial parts and paris saponin II induces G1/S-phase MCF-7 cell cycle arrest

In our previous research on Vietnamese medicinal plants, we found that the ethanolic extract of the aerial parts of Paris polyphylla var. chinensis exhibited cytotoxic effects in vitro in the MCF-7 human cancer cell line. Here, we used combined chromatographic separations to isolate six compounds including a new steroid glycoside, paripoloside A (3), and five known compounds, from the butanol extract of the aerial parts of P. polyphylla. We unambiguously elucidated their structures based on spectroscopic data (proton and carbon-13 nuclear magnetic resonance, heteronuclear single quantum coherence, heteronuclear multiple bond correlation, correlation spectroscopy, and high-resolution electrospray ionization mass spectroscopy data), and chemical reactions. Among the isolated compounds, paris saponin II (PSII) had the strongest cytotoxic effects against MCF-7 breast cancer cells. Interestingly, PSII significantly increased the expression of p53, p21, p27, and Bax protein levels and significantly suppressed the expression of cyclin D1 and retinoblastoma protein. These data suggest that PSII may induce G1/S phase cell cycle arrest and apoptosis pathway development in MCF-7 cells. Furthermore, the MCF-7 breast cancer cells mechanism of PSII was also investigated using molecular docking. Together, our results demonstrate that isolated compounds from P. polyphylla are promising candidates as breast cancer inhibitors.

SARS-CoV-2 main protease and papain-like protease inhibition by abietane-type diterpenes isolated from the branches of Glyptostrobus pensilis using molecular docking studies

Using various chromatographic methods, five abietane-type diterpenes were isolated from the branches of Glyptostrobus pensilis for the first time. The chemical structures of the isolates were identified by modern spectroscopic techniques, including ¹H and ¹³C nuclear magnetic resonance spectroscopy and by comparison with the literature. In addition, the binding potential of the isolated compounds to replicase protein, SARS-CoV-2 main protease and papain-like protease, were examined using molecular docking studies. In silico results suggested that G. pensilis as well as abietane-types diterpenes are potential candidates for the prevention and treatment of SARS-CoV-2.