Asiaticasics A-O, structurally intriguing coumarins from Toddalia asiatica with potential inflammatory inhibitory activity.

Ethyl acetate fraction of Toddalia asiatica was fractionated to yield fifteen previously undescribed prenylated coumarins, asiaticasics A-O (1-15) along with nine (16-24) known derivatives. The structures of these undescribed coumarins were established by spectroscopic analysis and reference data. Biological activity evaluation showed that compound 3 with the IC50 value of 2.830 µM and compound 12 with the IC50 value of 0.682 µM owned anti-inflammatory activity by detecting the rate of lactate dehydrogenase release in pyroptosis J774A.1 cells. The results showed that the expression of Caspase-1 and IL-1ß was decreased in a dose-dependent manner in the compound 12 treatment group, suggesting that compound 12 may reduce pyroptosis by inhibiting NLRP3 inflammasome. To further determine that compound 12 treatment can inhibit macrophage pyroptosis, morphological observation was performed and the results were consistent with the bioactivity evaluation.

Euphzycopins A - D, macrocyclic diterpenoids with potential anti-inflammatory activity from Euphorbia Helioscopia.

Four new diterpenoids (1-4) and four known diterpenoids (5-8) were purified from the whole plant of Euphorbia helioscopia L. Compounds 1 and 2 were jathophanes diterpenoids with a 5/12 polycyclic systems, compound 3 was rhamofolane diterpenoid with a 5/10 bicyclic skeleton and compound 4 was a rare class of euphorbia diterpenes featuring an unusual 5/10 fused ring system. Anti-inflammatory activity tests were conducted on the separated compounds, indicating that compound 4 had significant inhibitory effect on NLRP3 inflammasome with an IC50 value of 7.75 µM. Further, the inhibitory effect of 4 was determined using immunofluorescence assays.

Bioactive diterpenoids isolated from the twigs and leaves of Casearia velutina.

Nine previously undescribed clerodane-type diterpenoids (1-9), named caseabalanspenes A-I, along with six know compounds (10-15), were isolated from the twigs and leaves of Casearia velutina. Spectroscopic data (1D and 2D NMR) analysis permitted the definition of their structures and then determination of the molecular formula of the compound by high resolution mass spectrometry (HR-ESI-MS). It is worth noting that compound 7 contains N- heterocycle. Compounds 1-8 were tested the anti-inflammasome activity, and compound 3 exhibited potent activity and decreased LDH level in a dose-dependent manner, with IC50 values of 2.90 µM.

Nudifloids A-N, structurally diverse 3,4-seco-labdane diterpenoids from Callicarpa nudiflora with inflammatory inhibitory activity.

Fourteen undescribed seco-type diterpenoids, named nudifloids A-N, together with ten known analogs, were isolated from the leaves of Callicarpa nudiflora. Nudifloids A-N had a characteristic 3,4-seco-labdane-type diterpenoid skeleton, whereas nudifloids A-C and K-N were 3,4-seco-norditerpenoids. Nudifloid A was the first example of a 3,4-seco-12,13,14,15,16-quartnor-labdane diterpenoid, with a seven-membered lactone ring formed through esterification between C-3 and C-11. Nudifloids B and C were a pair of highly modified 3,4-seco-labdane nor-diterpenoid epimers, of which C-2 and C-18 were cyclized together to form a cyclohexene fragment. The structures of these undescribed diterpenoids were established by spectroscopic analysis and reference data. The anti-inflammatory activity of diterpenoids in rich yield was evaluated by analyzing the inhibition of lipopolysaccharide plus nigericin-induced pyroptosis in J774A.1 cells. Nudifloids D and E exhibited prominent anti-NLRP3 inflammasome activity, with IC50 values of 1.80 and 1.59 µM, respectively. Cell permeability assays revealed that nudifloid D inhibited pyroptosis, which could ameliorate inflammation by blocking the activation of the NLRP3 inflammasome.

16,17-dinor-abietane diterpenoids from Casearia kurzii.

Eleven undescribed 16,17-dinor-abietane diterpenoids, caseazins A-K (1-11), and ten known diterpenoids (12-21) were isolated from the twigs and leaves of Casearia kurzii (Flacourtiaceae). Caseazins A-K were the first abietane -type dinorditerpenoids to have been isolated from the plant of Casearia kurzii. Their chemical structures were elucidated using a combination of 1D and 2D NMR spectroscopy and mass spectrometry. The absolute configurations of 5 and 10 were established by electronic circular dichroism calculations. Moreover, compounds 2, 3, 13, 14, and 18 exhibited anti-inflammatory activity with IC50 values of 0.17, 0.36, 6.55, 1.30, and 4.53 µM, respectively. IL-1ß and caspase-1 analyses suggested that compound 14 inhibited NLRP3 inflammasome activation and blocked macrophage pyroptosis.

Chemical constituents from the twigs and leaves of Picrasma quassioides.

Two new compounds, including a norsesquiterpenoid, annuionone H (1), and a quassinoid, picraqualide G (2), along with eleven known compounds (3-13), were isolated from the twigs and leaves of Picrasma quassioides. Comprehensive spectroscopic analyses and NMR calculation with DP4+ analysis were used to identify their structures. Moreover, of all these compounds, compound 4 showed a week inhibition rate in the anti-inflammatory screening results against mouse macrophage J774A.1 cell.

Chemical Constituents of the Branches and Leaves of Picrasma chinensis P.Y. Chen and Tyrosinase Inhibiting Activity.

One new alkaloid, picrasine A, two new quassinoids, picralactones A-B, together with eleven known compounds were isolated from Picrasma chinensis P.Y. Chen. The structures of these compounds were determined using 1D and 2D NMR, HR-ESI-MS, and IR spectroscopic data, and by comparison with published data. Some compounds were tested for tyrosinase inhibiting activity, however, none of them exhibited strong inhibitory effects.

Caseatardies A-K, eleven undescribed clerodane diterpenoids isolated from Casearia tardieuae and their anti-inflammatory activity.

A phytochemical investigation to obtain bioactive substances as lead compounds or agents for anti-inflammatory led to the obtainment of eleven previously undescribed clerodane diterpenoids, named caseatardies A-K (1-11), and four known clerodane diterpenoids (12-15) from the twigs and leaves of Casearia tardieuae. The structural elucidation of these clerodane diterpenoids was based on 1D and 2D-NMR spectroscopy (COSY, HSQC, HMBC and ROESY) as well as high resolution mass spectrometry (HR-ESI-MS). The relative configurations were defined by ROESY correlations. The anti-inflammatory activity of all the isolated compounds was screened and compound 15 decreased LDH level in a dose-dependent manner, showing IC50 value of 2.89 µM.

Ten new prenylated flavonoids from Macaranga denticulata and their antitumor activities.

Ten new prenylated flavonoids, named denticulains A-J (1-10), together with seven known prenylated flavonoids (11-17) were isolated from Macaranga denticulata. Their structures were elucidated on the basis of detailed spectroscopic analysis and by comparison with literature data. In addition, compounds 1 and 14 inhibited the proliferation of SW620 and HCT-116 cell lines with an IC50 value of 46.08 µM and 56.83 µM, respectively.

The discovery of potentially active diterpenoids to inhibit the pyroptosis from Callicarpa arborea.

Pyroptosis is a programmed-inflammatory cell death, which leads to release of inflammatory cellular contents and formation of inflammation. Uncontrollable pyroptosis can result in serious immune diseases, such as cytokine release syndrome (CRS), sepsis, disseminated intravascular coagulation (DIC), and acute organ damage, including acute respiratory distress syndrome (ARDS) and acute kidney injury (AKI). Members of the Callicarpa genus are significant raw materials for traditional Chinese medicine, widely used for analgesia, hemostasis, and anti-inflammation. Previously, we have reported some ent-clerodane diterpenoids from Callicarpa arborea, shown potent inhibitory effects against pyroptosis. In this study, we went on investigating this kind of diterpenoids, and yielded 66 ent-clerodane diterpenoids, including 52 new compounds, from Callicarpa arborea. Their structures featured with a 5/6- (1-25) or a 6/6- (26-66)-fused double-ring scaffolds, were elucidated using spectroscopic data, electrostatic circular dichroism (ECD) and X-ray diffraction analyses. Screening for the inhibitory activity against pyroptosis by detecting of IL-1ß secretion in J771A.1 cells, revealed 28 compounds with an IC50 below 10.5 µM. Compound 1 was the most potent with an IC50 of 0.68 µM and inhibited the J774A.1 macrophage pyroptosis by blocking the NLR pyrin domain containing 3 (NLRP3) inflammasome activation. An in vivo study further revealed that compound 1 decreased infiltration of CD11b + F4/80 + macrophages into lung and attenuated the lipopolysaccharide (LPS)-induced lung injury. Taken together, this study indicated the potential of compound 1 as a candidate for pyroptosis-related inflammation treatment, as well as provided the chemical and pharmacological basis for the further development of Callicarpa genus as a herbal medicine.

Euphzycopias A-I, macrocyclic diterpenes with NLRP3 inflammasome inhibitory activity from Euphorbia helioscopia L.

A phytochemical investigation was conducted on Euphorbia helioscopia, resulting in the isolation of thirteen compounds, including nine undescribed diterpenoids, Euphzycopias A - I (1-9), of which the skeletons of compounds 1-4 were found in E. helioscopia L. Compounds 1-3 had 5/7/6 cyclic systems, while compound 4 had a 4/11 polycyclic system with a 4,7-cyclic ether between C-4 and C-7. The anti-inflammasome test using the isolated compounds (1-6, 8-13) showed that the diterpenes from E. helioscopia L. had a strong inhibitory effect on NLRP3 inflammasomes with IC50 values of 3.34-14.92 µM.

Leojaponin inhibits NLRP3 inflammasome activation through restoration of autophagy via upregulating RAPTOR phosphorylation.

ETHNOPHARMACOLOGICAL RELEVANCE: Duan Teng Yimu decoction is a Chinese herbal medicine compound with proven therapeutic effects on inflammasome-related diseases, such as rheumatoid arthritis. This decoction consists of three Chinese herbal medicines, including Leonurus japonicus (L. japonicus), which promotes the blood circulation and exhibits detumescence activity, traditionally curing gynecologic and inflammasome diseases. AIM OF THE STUDY: To explore the anti-inflammasome activity and the underlying mechanisms of action of the compounds from L. japonicus. MATERIALS AND METHODS: A series of compounds were isolated from L. japonicus. Their anti-inflammasome activities were evaluated in macrophages that were co-stimulated by lipopolysaccharide (LPS) and NLRP3 inflammasome inducers. NLRP3 inflammasome formation and apoptosis speck like containing a CARD (ASC) oligomerization were evaluated by immunofluorescent microscopy and Western blot analysis. The regulation of autophagy after treatment of this compound was also evaluated. Lastly, in vivo activity of Leojaponin was analyzed in a mouse acute gouty arthritis model. RESULTS: Here we show that Leojaponin, a diterpenoid compound from L. japonicus, suppressed lactate dehydrogenase and IL-1ß release in Nigericin-stimulated macrophages in a pyroptosis model. Leojaponin inhibits NLRP3 inflammasome activation in both J774A.1 cells and bone marrow-derived macrophages in a dose dependent manner. Moreover, Leojaponin suppressed NLRP3-mediated ASC specks formation and ASC oligomerization. These activities of Leojaponin depend on restoration of autophagy via promoting RAPTOR phosphorylation. Furthermore, Leojaponin ameliorated monosodium urate (MSU)-induced acute gouty arthritis in vivo. CONCLUSION: Our findings suggest that Leojaponin inhibits NLRP3 inflammasome activation through enhancing autophagy via RAPTOR phosphorylation, thereby highlighting Leojaponin as a potent drug for inflammasome-related diseases.

Diterpenoids from Callicarpa rubella and their in vitro anti-NLRP3 inflammasome activity.

Nine new diterpenoids, Rubellacrns A - I (1-9), including five isopimaranes (1-4, 9), four pimaranes (5-8), together with five known isopimarane analogues (10-14), were isolated from Callicarpa rubella. The structures of these compounds were unambiguously established by HR-ESIMS and NMR spectroscopic data, the absolute configurations of compounds 5 and 9 were determined by ECD. All the isolated compounds were tested for their anti-inflammatory effects and compounds 2 and 11-14 showed NLRP3-inflammasome inhibitory activity with IC50 values ranging from 7.02 to 14.38 µM.

Toonaolides A-X, limonoids from Toona ciliata: Isolation, structural elucidation, and bioactivity against NLRP3 inflammasome.

Twenty-four new limonoids, toonaolides A-X (1-24), characterized with an α,ß-unsaturated-γ-lactone A-ring were isolated from the twigs of Toona ciliata. Their structures and absolute configurations were elucidated by spectroscopic data, X-ray diffraction crystallography, and quantum chemistry calculations. Most of the isolated compounds (except 9, 18, and 24 which possessed the maleimide ring) featured the rare 21-hydroxybutenolide or 23-hydroxybutenolide moieties. In particular, compound 1 has an unprecedented limonoid architecture with 6/6 cis-fused A/B ring system and 2 has an unusual tetrahydrofuran ring B skeleton, featuring a 7/5/6/5 ring system. The biological evaluation showed that compounds 9, 11, 12, 14, and 18 exhibited significantly anti-NLRP3 inflammasome activity with IC50 values ranging from 3.2 to 9.7 µM. Analysis of IL-1ß and caspase-1 expression revealed that compounds 11 and 12 are selective inhibitors of NLRP3 inflammasome, which could ameliorate cell pyroptosis by blocking NLRP3 inflammasome activation.

Luteolin-7-methylether from Leonurus japonicus inhibits estrogen biosynthesis in human ovarian granulosa cells by suppression of aromatase (CYP19).

Leonurus japonicus (motherwort) has been widely used to treat gynecological disorders, in which estrogen is often dysregulated, for a long time in China and other Asian countries. However, the chemical constituents and mechanisms underlying the activity of this medicinal plant are not fully understood. Seventeen of forty-six tested natural products from L. japonicus showed stimulatory or inhibitory effects on estrogen biosynthesis with different potency in human ovarian granulosa-like KGN cells. Luteolin-7-methylether (XLY29) potently inhibited 17ß-estradiol production (IC50: 5.213 µM) by decreasing the expression of aromatase, the only enzyme in vertebrates that catalyzes the biosynthesis of estrogens, but had no effect on the catalytic activity of aromatase. XLY29 decreased the expression of aromatase promoter I.3/II, and suppressed the phosphorylation of cAMP response element-binding protein. XLY29 potently inhibited phosphorylation of p38 mitogen-activated protein kinase and AKT but had no effect on phosphorylation of extracellular signal-regulated kinase and c-Jun N-terminal kinase. XLY29 also decreased the serum 17ß-estradiol level and disturbed estrous cycle in mice. These results suggest that modulation of estrogen biosynthesis is a novel effect of L. japonicus, and XLY29 warrants further investigation as a new therapeutic means for the treatment of estrogen-related diseases.

Clerodane diterpenoids with potential anti-inflammatory activity from the leaves and twigs of Callicarpa cathayana.

Phytochemical investigation of the leaves and twigs of Callicarpa cathayana led to the isolation of six new clerodane diterpenoids, cathayanalactones A-F (1-6), together with seven analogues (7-13). Their structures were established by extensive NMR analyses together with experimental and calculated ECD spectra analyses. Compounds 1, 2, 3, 7 and 11 showed inhibitory activities on lipopolysaccharide-induced nitric oxide production in RAW264.7 cells.

Chemical Space and Biological Target Network of Anti-Inflammatory Natural Products.

Natural products (NPs) are a promising source of anti-inflammatory molecules for the development of drugs. Despite there being an abundance of reports of large numbers of NPs having bioactivity in preliminary cell-based assays of anti-inflammatory potential, their further optimization and exploration are limited by the lack of a comprehensive understanding of their effective scaffold structure or biological targets. To facilitate target-based studies of anti-inflammatory NPs, the details of 665 NPs reported to have anti-inflammatory activity were extracted from the literature and compiled into a data set we termed InflamNat. The physicochemical properties of the NPs were analyzed, and the distribution of their structures and scaffolds is presented. A compound-target network was constructed from data in the PubChem Bioassay database. The results demonstrated that, compared to natural anticancer compounds in the NPACT database, compounds from the InflamNat data set contained a comparable distribution of compound types but with a higher proportion satisfying Lipinski's rule. The all-atom structures and scaffold of the compounds were diverse and barely convergent, with flavonoids and triterpenoids being the groups with the greatest abundance. The biological targets of the InflamNat compounds were identified as belonging to a variety of protein families that had varied function. Seventy-two percent of InflamNat compounds involved in the network were identified as having more than one biological target, highlighting the potential for multitarget anti-inflammatory drug development. In conclusion, anti-inflammatory NPs provide a good library for the screening of target-based leads or fragment-based drug design. Thus, elucidation of their biological targets is fundamental for either a specific single-target or multitarget drug development strategy. Meanwhile, a large proportion of the chemical space of anti-inflammatory NPs is still unexplored, with novel active scaffolds remaining to be discovered.

In Vitro Human Dihydroorotate Dehydrogenase Inhibitory, Anti-inflammatory and Cytotoxic Activities of Alkaloids from the Seeds of Nigella glandulifera.

Four new dolabellane-type diterpene alkaloids, glandulamines A - D (1:  - 4: ), together with twelve known compounds (5:  - 16: ), were isolated from the seeds of Nigella glandulifera using repeated column chromatography and semipreparative HPLC. The structures of 1:  - 16: were elucidated based on NMR data analysis, HRMS experiments and other spectroscopic interpretations. The absolute configuration of 5: was determined by single-crystal X-ray diffraction data for the first time. Compounds 10: and 12: showed human dihydroorotate dehydrogenase inhibitory activity with IC50 values of 61.1 ± 5.3 and 45.9 ± 3.0 µM, respectively. Molecular docking of the active compound 12: and positive control teriflunomide on the inhibitor-binding site of human dihydroorotate dehydrogenase was subsequently performed to visualize the interaction pattern. In addition, compounds 8: and 10: exhibited inhibitory effects against lipopolysaccharide-induced nitric oxide production with inhibition rates of 61 and 41%, respectively, at the concentration of 10 µM. Compounds 9: and 12: showed cytotoxic activities with cell viability varying from 29 ~ 57% at 100 µM against T98G, U87, U251, and GL261 glioma cancer cell lines. These data provide new insights on the pharmacologically active compounds of this plant widely used in folk medicine.

Phytochemistry and pharmacology of the genus Leonurus: The herb to benefit the mothers and more.

Plants belonging to the genus Leonurus, also named motherwort, are traditionally used for anti-gynecological disorder in East Asia, and for sedative in Europe. Chemical investigation of the genus Leonurus not only enriched the natural products library, but also enlarged the pharmacological application of this traditional herb. In this review, we systematically summarized the structures of 259 compounds isolated from the genus Leonurus, featured with 147 labdane diterpenoids. The reported bioactivity studies up to 2017 are presented in the second part, with the main focus on the isolated compounds and also concerning the extracts. In addition to the traditional uterine contraction and sedative activity, recently the cardiovascular protection effect of leonurine has drawn most attention. Other than that, neuroprotection, anti-inflammation, anti-cancer, anti-platelet aggregation and many other activities have been assigned to various compounds from the genus Leonurus. Among 70 bioactivity references cited in this review, 57% of them were concentrated on two alkaloids (leonurine and stachydrine), whereas only 20% are about the 147 diterpenoids. Anti-inflammation is the major bioactivity discovered so far for the labdane diterpenoids from the genus Leonurus, whose further therapeutic potential still remains for exploration.

Highly oxygenated lanostane-type triterpenoids and their bioactivity from the fruiting body of Ganoderma gibbosum.

Eight new highly oxygenated lanostane triterpenes, gibbosic acids A-H (1-8), along with three known ones (9-11), were isolated from the fruiting body of Ganoderma gibbosum. The structures of new isolates were assigned by NMR and HRESIMS experiments. The absolute configurations of 1 were further confirmed by single crystal X-ray diffraction data and computational ECD methods. Immunoregulatory effect and anti-inflammatory activities of these compounds were screened in murine lymphocyte proliferation assay and in lipopolysaccharide (LPS)-stimulated RAW-264.7 macrophages, respectively. Compound 2 exhibited immunostimulatory effect both in lymphocyte proliferation assay without any induction and ConA-induced mitogenic activity of T-lymphocyte, and the proportion of lymphocyte proliferation at the concentration of 0.1µM are 20.01% and 21.40%, respectively.