Research progress on the role and inhibitors of Keap1 signaling pathway in inflammation.

Inflammation is a protective mechanism against endogenous and exogenous pathogens. It is a typical feature of numerous chronic diseases and their complications. Keap1 is an essential target in oxidative stress and inflammatory diseases. Among them, the Keap1-Nrf2-ARE pathway (including Keap1-Nrf2-HO-1) is the most significant pathway of Keap1 targets, which participates in the control of inflammation in multiple organs (including renal inflammation, lung inflammation, liver inflammation, neuroinflammation, etc.). Identifying new Keap1 inhibitors is crucial for new drug discovery. However, most drugs have specificity issues as they covalently bind to cysteine residues of Keap1, causing off-target effects. Therefore, direct inhibition of Keap1-Nrf2 PPIs is a new research idea. Through non-electrophilic and non-covalent binding, its inhibitors have better specificity and ability to activate Nrf2, and targeting therapy against Keap1-Nrf2 PPIs has become a new method for drug development in chronic diseases. This review summarizes the members and downstream genes of the Keap1-related pathway and their roles in inflammatory disease models. In addition, we summarize all the research progress of anti-inflammatory drugs targeting Keap1 from 2010 to 2024, mainly describing their biological functions, molecular mechanisms of action, and therapeutic roles in inflammatory diseases.

Schisandra chinensis (Turcz.) Baill neutral polysaccharides alleviate Parkinson's disease via effectively activating MCL-1 expression regulation of autophagy signaling.

The purified neutral polysaccharide fraction, namely SBP-1, was isolated and characterized from Schisandra chinensis (Turcz.) Baill crude polysaccharides, which have anti-Parkinson's disease activity were investigated in vivo and in vitro. Experiments have shown that the main chain of SBP-1 was Glcp-(1→, →4)-Glcp-(1→ and →4,6)-Glcp-(1→. We also revealed the effect of SBP-1 on the PD mice model and the potential underlying molecular mechanism. The results showed that SBP-1 administration improved behavioral deficits, increased tyrosine hydroxylase-positive cells, attenuated loss of dopaminergic neurons in MPTP-exposed mice, and reduced cell death induced by MPP+. The MCL-1 was identified as the target of SBP-1 by the combination of docking-SPR-ITC, WB, and IF experiments. Subsequently, the study showed that SBP-1 could target MCL-1 to enhance autophagy with a change in the apoptotic response, which was further demonstrated by a change in LC3/P62, PI3K/AKT/mTOR, and possesses a change in the expression of BCL2/BAX/Caspase3. These results demonstrate that SBP-1 may protect neurons against MPP+ or MPTP-induced damage in vitro and in vivo through enhancing autophagy. In summary, these findings indicate that SBP-1 and S. chinensis show potential as effective candidates for further investigation in the prevention and treatment of PD or associated illnesses, specifically through autophagy apoptotic-based mechanisms.

Three new compounds from the fruits of Solanum virginianum L. and their anti-inflammatory activities.

Three new compounds 1-glyceryl 9(ß), 10(α), 11(ß)-trihydroxy-12(Z)-octadecenoate, 2'S-20-O-p-hydroxyphenylpropionyloxy-20-hyd-roxyarachidic acid glycerol ester (2), 3-O-α-l-arabinopyranosyl-(1→6)-ß-d-glucopyranoside of ethyl (3S)-hydroxybutanoate (3), as well as a new natural product (4) were isolated from the fruits of Solanum virginianum L. The structures of 26 compounds were determined by comprehensive spectroscopic analyses, NMR calculation, chemical methods, and comparisons of spectroscopic data. Compounds 2 and 16 exhibited good anti-inflammatory activity in the LPS-induced RAW 264.7 inflammatory model with IC50 values of 16.75 ± 1.54 and 22.43 ± 2.01 µM, respectively.

Undescribed steroidal alkaloids from the bulbs of Fritillaria ussuriensis Maxim and their anti-inflammatory activities.

In total, 16 undescribed steroidal alkaloids (1-16), along with nine known ones (17-25), were isolated from the bulbs of Fritillaria ussuriensis Maxim. Among the undescribed compounds mentioned, compounds 1-6, 8 bearing an 16ß-hydroxy substituent, as well as compounds 13 and 14 exhibited an unusual seven-membered skeleton. Their structures were established based on extensive spectroscopic analyses, including HRESIMS and NMR (1D and 2D), and comparison with the data reported in the literature. Furthermore, all the compounds were evaluated for their anti-inflammatory effect on the NO production of LPS-stimulated RAW264.7 cells. Compounds 1, 4, 11, 15, 22 and 24 could significantly inhibit NO production with IC50 values below 10 µM.

Triterpenoids from the leaves of Eleutherococcus sessiliflorus, and their antiproliferative activities in TNF-α induced HFLS-RA cells.

Five undescribed elesesterpenes L-U, along with nine known 3,4-seco-lupane-type triterpenoids were isolated from the leaves of Eleutherococcus sessiliflorus (Rupr. & Maxim.) S. Y. Hu. Elesesterpene L-S, and U were lupane-type triterpenoids, whereas elesesterpene T was an oleanane-type triterpenoid, probably artifact, as suggested by LC-MS analysis. Out of the nine known compounds, five were initially identified in E. sessiliflorus. Moreover, their structures were definitively determined using spectroscopic analyses, and the absolute configurations of elesesterpenes L-M and sachunogenin 3-O-glucoside were clarified using X-ray crystallographic techniques. The absolute configuration of elesesterpene T was determined by measuring and calculating its ECD. In addition, all compounds were tested to examine their ability to inhibit the proliferation of HFLS-RA cells induced by TNF-α in vitro. Elesesterpene M, chiisanogenin, chiisanoside, and 3-methylisochiisanoside significantly inhibited HFLS-RA proliferation.

Fourteen undescribed steroidal saponins from Solanum capsicoides leaves and their neuroprotective effects.

A total of 14 previously undescribed steroidal saponins named capsicsaponins A-N were isolated from the leaves of Solanum capsicoides, encompassing various types, including cholesterol derivatives and pseudospirostanol saponins. The structures of all compounds were determined through comprehensive analysis of spectroscopic data (1D NMR and 2D NMR), along with physicochemical analysis methods (acid hydrolysis, OR, and UV). Moreover, in the H2O2-induced pheochromocytoma cell line model, compounds 1-14 were screened for their neuroprotective effects on cells. The bioassay results demonstrated compounds 8-14 were able to revive cell viability compared to the positive control edaravone. The damage neuroprotection of the most active compound was further explored.

A new triterpenoid saponin and a new natural saponin from the roots of Bupleurum scorzonerifolium willd.

Sixteen triterpenoid saponins were isolated from the roots of Bupleurum scorzonerifolium Willd., including a new triterpenoid saponin and new natural saponin that was characterised by NMR for the first time, along with 14 known triterpenoid saponins. The structures of the compounds were established by 1D and 2D NMR spectroscopy, HR-ESI-MS, and comparison with the literature. The cytotoxic activity of the compounds against 4T1 cells was determined using the CCK8 method. Compounds 9 and 6 showed the strongest cytotoxic activity with IC50 values of 2.75 ± 0.86 and 3.78 ± 0.50 µM, respectively. Compounds 2-5 and 8 showed potent cytotoxic activity. Compounds 14 and 16 showed moderate cytotoxicity.

Seven new triterpenoids from the roots of Adenophora tetraphylla (Thub.) Fisch.

Seven new triterpenoids, named Adeterpenoids A-G (1-7) and eight known compounds (8-15), were isolated from 70% ethanol extract of the roots of Adenophora tetraphylla (Thub.) Fisch. The compounds from it were separated by column chromatography techniques such as silica gel, ODS, and preparative liquid chromatography. Their structures were clarified based on extensive spectral analysis (1D, 2D-NMR, HR-ESI-MS, IR, UV, and CD) and comparison with the literature. At the same time, all compounds were evaluated for their cytotoxic activity against the LN229 (human glioma cell line). The results showed that compounds 2, 5, 6, 13, and 14 had a significant inhibitory effect on LN229 cells.

Effects of Viscum coloratum (Kom.) Nakai on collagen-induced rheumatoid arthritis.

ETHNOPHARMACOLOGICAL RELEVANCE: Viscum coloratum (Kom.) Nakai has been traditionally used in China for nearly a thousand years to treat rheumatic diseases. However, its efficacy and mechanisms in treating rheumatoid arthritis (RA) have not been demonstrated. AIM OF THE STUDY: To investigate the anti-arthritic effects and molecular mechanisms of Viscum coloratum (Kom.) Nakai on collagen-induced arthritic mice through network pharmacology technology and experimental validation. MATERIALS AND METHODS: First, the main ingredients of the extract of Viscum coloratum (Kom.) Nakai (EVC) were identified through chemical composition characterization using Ultra Performance Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS). Then, the collagen-induced arthritis (CIA) model was established in DBA/1 J mice and the ameliorative effects of EVC on the progression of CIA mice were evaluated by oral treatment with different doses of the EVC for 28 days. After that, cytokine antibody microarray assay was used to detect the levels of multiple inflammation-related cytokines and chemokines in each group, and performed Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) enrichment analysis. Subsequently, the potential target for the effective chemical components of EVC in treating RA was identified using various databases. Additionally, a drug-disease target protein-protein interaction network (PPI) was conducted using Cytoscape for visualization and clustering, while GO and KEGG enrichment analyses were performed with the Metascape database. Finally, identified phenotypes and targets by network pharmacology analysis were experimentally validated in vivo. RESULTS: Treatment with EVC significantly suppressed the severity of CIA with a dramatic reduction of paw swelling, arthritis index, levels of IgGs (IgG, IgG1, IgG2a, and IgG2b), multi-inflammation-related cytokines and chemokines on the progression of CIA. Histopathological examinations showed EVC could markedly inhibit inflammatory cell infiltration, tartrate-resistant acid phosphatase (TRAP) activity of osteoclast, and bone destruction. Furthermore, GO and KEGG enrichment analyses revealed that EVC could ameliorate RA by inhibiting osteoclast differentiation and regulating multiple signaling pathways including Osteoclast differentiation, IL-17, and TNF. PPI network analysis demonstrated that AKT1, MMP9, MAPK3, and other genes were highly related to EVC in treating RA. Finally, we proved that EVC could inhibit the expression of NFTAc1, MMP9, Cathepsin K, and AKT which were closely related to osteoclast activity. CONCLUSIONS: EVC could treat RA through multiple components, multiple targets, and multiple pathways. The present study demonstrated the therapeutic efficacy of EVC and its molecular mechanisms in treating RA, indicating that it would be a potent candidate as a novel botanical drug for further investigation.

Three new schinortriterpenoids from the leaves of Schisandra chinensis (Turcz.) Baill.

Three undescribed schinortriterpenoids, schinensilactones D-F (1-3), together with five known ones, namely, wuweizidilactone A (4), wuweizidilactone C (5), wuweizidilactone F (6), wuweizidilactone J (7) and wuweizidilactone N (8), were isolated from the leaves of Schisandra chinensis (Turcz.) Baill. The structures of new compounds were established by analysis of their spectroscopic data including MS, IR, 1D- and 2D-NMR spectra. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction and calculated electronic circular dichroism (ECD) spectra. All compounds were evaluated for their neuroprotective effects against H2O2-induced injury in human neuroblastoma SH-SY5Y cell lines. Cell viability was remarkably reduced to 52.33% in H2O2-treated cells. Compounds 5-7 exhibited moderate neuroprotective activities at 50 µM, with cell viability of 64.84%, 67.34% and 63.73%, respectively.

Study on the mechanism of Coptis chinensis Franch. And its main active components in treating Alzheimer's disease based on SCFAs using Orbitrap Fusion Lumos Tribrid MS.

ETHNOPHARMACOLOGICAL RELEVANCE: Coptis chinensis Franch. (CCF), as an extensively used traditional Chinese medicine, has therapeutic effects on Alzheimer's disease (AD), but its mechanism of action has not yet been elucidated. AIM OF THE STUDY: This study aims to reveal the mechanism of action of CCF via the gut-brain axis, and provide a new strategy for the clinical treatment of AD. MATERIALS AND METHODS: APPswe/PS1ΔE9 mice were used as AD models, and were given CCF extract by intragastric administration. Barnes maze was used to test the therapeutic effect of CCF on the treatment of AD. To reveal the mechanism of action of CCF in the treatment of AD, Vanquish Flex UHPLC-orbitrap fusion lumos mass was chosen to detect endogenous differential metabolite; MetaboAnalyst 5.0 was applied to derive relevant metabolic pathways; similarly, to explore the effects of CCF on the gut-brain axis, Vanquish Flex UPLC-Orbitrap fusion lumos mass was utilized to detect the changes in the content of SCFAs in AD mice after CCF administration; the prototype components and metabolites in CCF were identified by UPLC/ESI/qTOF-MS, then their effects on Bifidobacterium breve were explored. RESULTS: CCF shortened the latency time of AD mice, improved the target quadrant ratio of AD mice, and made the maze roadmap simpler of AD mice; CCF regulated fifteen potential metabolites of AD mice, interestingly, ILA (indole-3-lactic acid) in SCFAs (short-chain fatty acids) was also included; CCF acted on histidine and phenylalanine metabolic pathways of AD mice; CCF increased the contents of acetic acid and ILA in AD mice; magnoflorine, jatrorrhizine, coptisine, groenlandicine, thalifendine, palmatine, berberine, epiberberine, hydroxylated jatrorrhizine, and 3-methoxydemethyleneberberine in CCF were detected in fecal samples of AD mice; magnoflorine, palmatrubine, 13-methylberberine, berberine, coptisine, and palmatine promoted the growth of Bifidobacterium breve. CONCLUSIONS: we have demonstrated that CCF acts on the gut-brain axis by regulating SCFAs to treat AD.

Inositol Derivatives with Anti-Inflammatory Activity from Leaves of Solanum capsicoides Allioni

Eight new inositol derivatives, solsurinositols A-H (1-8), were isolated from the 70% EtOH extract of the leaves of Solanum capsicoides Allioni. Careful isolation by silica gel column chromatography followed by preparative high-performance liquid chromatography (HPLC) allowed us to obtain analytically pure compounds 1-8. They shared the same relative stereochemistry on the ring but have different acyl groups attached to various hydroxyl groups. This was the first time that inositol derivatives have been isolated from this plant. The chemical structures of compounds 1-8 were characterized by extensive 1D nuclear magnetic resonance (NMR) and 2D NMR and mass analyses. Meanwhile, the in vitro anti-inflammatory activity of all compounds was determined using lipopolysaccharide (LPS)-induced BV2 microglia, and among the isolates, compounds 5 (IC50 = 11.21 ± 0.14 µM) and 7 (IC50 = 14.5 ± 1.22 µM) were shown to have potential anti-inflammatory activity.

Four new withanolides with anti-inflammatory activity from Datura inoxia Mill. leaves.

Four previously undescribed withanolides, datinolides A-D (1-4) and eight known withanolides (5-12), were separated from the 70% ethyl alcohol extract of Datura inoxia Mill. leaves. All structures were clarified by comprehensive spectroscopic analysis. Furthermore, all withanolides were assessed for their anti-inflammatory activity and results showed that 1 exhibited a fairly good suppression against nitric oxide generation in lipopolysaccharide-stimulated RAW 264.7 cells (IC50 = 10.33 ± 1.53 µM).

Six new secoiridoid glycosides from the stem barks of Syringa Reticulata (Bl.) Hara.

Six new secoiridoids, syrretosides E-J (1-6) and four known secoiridoids (7-10), were isolated from the stem barks of Syringa reticulata. Their structures were established by the 1D and 2D NMR spectra, HR-ESI-MS, and comparison with the literature. The cytotoxicity of the isolated monomeric compounds against RAW264.7 cells was investigated by the CCK8 assay, and the results showed that the individual compounds were not cytotoxic to RAW264.7. The anti-inflammatory activity of these compounds was evaluated using the LPS-induced RAW264.7 inflammatory cell model and the results showed that compounds 3-7 and 9 showed varying degrees of anti-inflammatory activity.

Two new terpenes from the aerial parts of Clematis chinensis Osbeck.

Two new acyclic sesquiterpenoids (1-2) and fourteen known monocyclic monoterpenoids (3-16) were isolated from the aerial parts of Clematis chinensis Osbeck. All compounds were isolated from C. chinensis for the first time. The structures of all compounds were characterized by spectroscopic methods (1 D, 2 D NMR and HRESIMS). In-vitro cytotoxic activity against two human cancer cell lines (MGC-803 and Ishikawa) of all the compounds were evaluated by CCK-8 assay.

Four new polyacetylenes from the roots of Saposhnikovia divaricata.

Four new polyacetylene substances, sadivaethynes A-D, were isolated from the ethanol extract of the roots of Saposhnikovia divaricata (Turcz.) Schischk using repeated column chromatography. Structural elucidation of compounds 1-4 was established by 1D and 2D NMR spectra referring to the literature, together with high-resolution mass spectrometric analysis. All compounds were evaluated for cytotoxicity against two human cancer cell lines (MGC-803, Ishikawa) in vitro.

Seven undescribed steroids from the leaves of Datura metel L.

Extraction of Datura metel L. leaves with ethanol as a solvent gave a group of steroids, including two unique 1,10-seco-withanolides (1, 4), an unusual nitrogen-containing withanolides (2), one undescribed saponin (3), two withanolides with a carbohydrate (5, 6), and one C21 steroid (7). These compounds' structures were identified based on HR-ESI-MS and 1H, 13C NMR data analyses, also compared with data from the document. Some compounds showed moderate inhibition on NO production in lipopolysaccharide-stimulated RAW 264.7 cells.

Five new sesquiterpenoids from the fruits of Acanthopanax senticosus (Rupr. & Maxim.) Harms.

Five new sesquiterpenoids named acasenterpene A-E (1-5) were isolated from the fruits of Acanthopanax senticosus. The structures of all compounds were elucidated by extensive spectroscopic data analyses (1D, 2D NMR, and HR-ESI-MS) combined with physico-chemical analysis methods (enzyme hydrolysis, optical rotation, and CD). The cytotoxicity of all compounds in vitro against four human cancer cell lines (MGC-803, Ishikawa, LN-229 and SMMC-7721) were evaluated by CCK-8 assay.

New indole alkaloids from the seeds of Datura metel L.

Four new indole alkaloids, daturametelindoles A-D (1-4) were isolated from the EtOAc soluble partition of the ethanol extract of the Datura metel seeds. The structures of the new compounds were determined based on spectroscopic evidence, including their 1D- and 2D-NMR spectra and mass spectrometry. In particular, compounds 1-4 were all racemes, confirmed by the optical rotations and CD spectra. Unfortunately, the chiral monomers were not obtained due to the amount, but the developments of their chiral separation and chiral resolution were completed. All isolated compounds were evaluated for cytotoxic effects against human gastric adenocarcinoma cells (SGC-7901), human hepatoma (Hepg2), and human breast cancer (MCF-7).