Targeted discovery of clerodane diterpenoids from Tinospora sinensis as immunomodulatory agents.

Under the guidance of MS/MS-based molecular networking, five new clerodane diterpenoid glucosides, tinosinesides R-V (1-5), along with 15 known diterpenoids (6-20), were isolated from the stems of Tinospora sinensis. Compound 1 represents the first example of diterpenoid bearing a thio sugar and compound 5 is the first 18,19-dinor-clerodane with cis-fused A/B ring. The structures of the new compounds were elucidated by spectroscopic means, and their absolute configurations were established on the basis of time-dependent density functional theory (TD-DFT) based electronic circular dichroism (ECD) calculation and chemical methods. Selected compounds were evaluated for their immunomodulatory effect and several compounds could enhance the proliferation of B lymphocytes. Preliminary mechanistic studies disclosed that 3 could promote B cell generation and inhibit B cell differentiation.

Azaphilone pigments from the marine-derived Penicillium sclerotium UJNMF 0503 and their neuroprotective potential against H2O2-induced cell apoptosis through modulating PI3K/Akt pathway.

Azaphilones represent a particular group of fascinating pigments from fungal source, with easier industrialization and lower cost than the traditional plant-derived pigments, and they also display a wide range of pharmacological activities. Herein, 28 azaphilone analogs, including 12 new ones, were obtained from the fermentation culture of a marine fungus Penicillium sclerotium UJNMF 0503. Their structures were elucidated by MS, NMR and ECD analyses, together with NMR and ECD calculations and biogenetic considerations. Among them, compounds 1 and 2 feature an unusual natural benzo[d][1,3]dioxepine ring embedded with an orthoformate unit, while 3 and 4 represent the first azaphilone examples incorporating a novel rearranged 5/6 bicyclic core and a tetrahydropyran ring on the side chain, respectively. Our bioassays revealed that half of the isolates exhibited neuroprotective potential against H2O2-induced injury on RSC96 cells, while compound 13 displayed the best rescuing capacity toward the cell viability by blocking cellular apoptosis, which was likely achieved by upregulating the PI3K/Akt signaling pathway.

Sesquiterpenoids and steroids from Eupatorium fortunei and their inhibitory effects on NO production.

Two heterodimers including a clovane-phenylpropanoid hybrid (1) and a clovane-menthane hybrid (2), five linear sesquiterpenoids incorporating a tetrahydrofuran ring (3-6 & 8), and four steroids (7 & 9-11), were separated from the ethanolic extract of a well-known aromatic and medicinal herb Eupatorium fortunei. Their structures were characterised by detailed analyses of spectroscopic data and comparison with known analogues, with seven (1-7) of them being described for the first time. The hybrids 1 and 2 represent the first examples of clovane type sesquiterpenoids hybridising with other class of natural products, and compounds 3-6 and 8 are first linear sesquiterpenyl constituents reported from the title species. All the isolates were evaluated for their inhibitory effect on the NO production induced by LPS in murine RAW264.7 macrophage cells, and 1, 7, 10 and 11 exhibited moderate activity with IC50 values in the range of 24.4-43.5 µM.

Anti-inflammatory Polyketides from an Endophytic Fungus Chaetomium sp. UJN-EF006 of Vaccinium bracteatum.

Seven new polyketides including three chromone derivatives (1-3) and four linear ones incorporating a tetrahydrofuran ring (4-7), along with three known compounds (8-10), were obtained from the fermentation of an endophytic fungus (Chaetomium sp. UJN-EF006) isolated from the leaves of Vaccinium bracteatum. The structures of these fungal metabolites have been elucidated by spectroscopic means including MS, NMR and electronic circular dichroism. A preliminary anti-inflammatory screening with the lipopolysaccharide (LPS) induced RAW264.7 cell model revealed moderate NO production inhibitory activity for compounds 1 and 4. In addition, the expression of three LPS-induced inflammatory factors IL-6, iNOS and COX-2 was also blocked by 1 and 4.

Bioactive neolignan, iridoid and flavonoid glycosides from the leaves of Vaccinium bracteatum.

Two neolignan glycosides including a new one (1), along with seven iridoid glycosides (3 - 9) and nine flavonoid glycosides (10 - 18), were isolated from the leaves of Vaccinium bracteatum. Their structures were established mainly on the basis of 1D/2D NMR and ESIMS analyses, as well as comparison to known compounds in the literature. The structure of 1 with absolute stereochemistry was also confirmed by chemical degradation and ECD calculation. Selective compounds showed antiradical activity against ABTS and/or DPPH. Moreover, several isolates also suppressed the production of ROS in RAW264.7 cells and exerted neuroprotective effect toward PC12 cells.

Indole Diterpenes from Mangrove Sediment-Derived Fungus Penicillium sp. UJNMF0740 Protect PC12 Cells against 6-OHDA-Induced Neurotoxicity via Regulating the PI3K/Akt Pathway.

In our chemical investigation into Penicillium sp. UJNMF0740 derived from mangrove sediment, fourteen indole diterpene analogs, including four new ones, are purified by multiple chromatographic separation methods, with their structures being elucidated by the analyses of NMR, HR-ESIMS, and ECD data. The antibacterial and neuroprotective effects of these isolates were examined, and only compounds 6 and 9 exhibited weak antibacterial activity, while compounds 5, 8, and 10 showed protective effects against the injury of PC12 cells induced by 6-hydroxydopamine (6-OHDA). Additionally, compound 5 could suppress the apoptosis and production of reactive oxygen species (ROS) in 6-OHDA-stimulated PC12 cells as well as trigger the phosphorylation of PI3K and Akt. Taken together, our work enriches the structural diversity of indole diterpenes and hints that compounds of this skeleton can repress the 6-OHDA-induced apoptosis of PC12 cells via regulating the PI3K/Akt signaling pathway, which provides evidence for the future utilization of this fascinating class of molecules as potential neuroprotective agents.

Sequencing and analysis of the complete mitochondrial genome of Eothenomys eleusis Thomas 1911 from China and its phylogenetic analysis.

The complete mitogenome sequence of Eothenomys eleusis Thomas 1911 was determined using PCR. A circular double-stranded structure makes up the mitochondrial genome of E. eleusis. The complete length of the mitochondrial genome is 16,419 bp. The mitochondrial genome of E. eleusis included 13 protein-coding genes, 1 control region, 22 tRNA genes, 2 rRNA genes and 1 origin of L strand replication. The total base composition of E. eleusis mitochondrial genome was A (32.6%), T (26.3%), G (13.6%) and C (27.5%). We found significant A-T skew in base composition, especially in control regions and protein-coding genes. E. eleusis was supported by bootstrap values of 100%. This study verifies the evolutionary status of E. eleusis in Myodini tribe of Cricetidae at the molecular level. The mitochondrial genome would be a significant supplement for the E. eleusis genetic background.

Anti-inflammatory labdane diterpenoids from the aerial parts of Leonurus japonicus.

Twenty-two labdane-type diterpenoids, including ten pairs of 15-epimers and a pair of 13,15-epimers, were obtained from the aerial parts of a well-known medicinal plant Leonurus japonicus Houtt. While these epimers were separated by chiral HPLC, their structures were established mainly via spectroscopic methods especially NMR, X-ray crystallography and ECD techniques. Among them, seventeen compounds, encompassing three pairs of solvolysis artefacts likely due to the use of ethanol as extracting solvent, were reported for the first time in the current work. Our preliminary anti-inflammatory screening demonstrated that seven diterpenoids displayed noteworthy inhibitory effect on the NO production in LPS-induced RAW264.7 cells. In addition, the release of pro-inflammatory factors TNF-α, IL-1ß and IL-6, as well as the expression of iNOS and COX-2 proteins, was also suppressed by the unreported 15,16-epoxy-6ß-hydroxy-15α-methoxy-7,16-dioxolabd-8,13-diene. Further investigation into the preliminary anti-inflammatory mechanism of this compound indicated that it could block the activation of NF-κB signaling pathway.

Identification of Small-Molecule Bioactive Constituents from the Leaves of Vaccinium bracteatum Confirms It as a Potential Functional Food with Health Benefits.

The health benefits of Vaccinium bracteatum are well recorded in ancient Chinese medical books and were also demonstrated by modern researches. However, the relationship between its beneficial functions and specific chemical constituents has not been fully characterized. This study investigated the bioactive small-molecule constituents in the leaves of V. bracteatum, which afforded 32 compounds including ten new ones (1-9) and ten pairs of enantiomers (9-18). Their structures with absolute configurations were elucidated by spectroscopic methods, especially nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) analyses, with 1-4 bearing a novel revolving-door shaped scaffold. While half-compounds exhibited decent antioxidant activity by scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, all except 19 and 20 exerted significant capturing activity against diammonium 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS) radicals. In addition, the new iridoids 1, 5, 6, and 7 exerted apparent neuroprotective activity toward PC12 cells, with 1 being comparable to the positive control, and selective compounds also displayed anti-diabetic and anti-inflammatory properties by inhibiting α-glucosidase and NO production, respectively. The current work revealed that the bioactive small-molecule constituents could be closely related to the functional food property of the title species.

Methyl 2-naphthoates with anti-inflammatory activity from Morinda officinalis.

Chemical fractionation of the EtOH extract of the roots of a traditional Chinese herb, Morinda officinalis, afforded an array of methyl 2-naphthoate derivatives (1-9) including four pairs of enantiomers (1-4), two pimarane diterpenes and two ursane triterpenoids. Among them, eight compounds (1a/1b-3a/3b, 11 and 13) were reported in the current work for the first time. The structures of the new compounds, including their absolute configurations, were defined by spectroscopic analyses in combination with quantum chemical electronic circular dichroism (ECD) and gauge-independent atomic orbital (GIAO) NMR calculations. All the isolates were evaluated for their inhibitory effect on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in murine RAW264.7 macrophage cells, and the enantiomers 1a and 3b exhibited moderate activity with IC50 values of 41.9 and 26.2 µM. Meanwhile, compound 3b also dose-dependently inhibited the secretion of two pro-inflammatory cytokines TNF-α and IL-6 in the same cell model.

Isolation, Structure Characterization, Total Synthesis and Biological Evaluation of Cinnamic Acid Derivatives from Tinospora sagittata.

Thirteen cinnamic acid derivatives (1-13), including six formerly unreported hybrids incorporating different short-chain fatty acid esters (1-6), have been obtained and structurally elucidated from an ethnological herb Tinospora sagittata. The structures of them have been established by spectroscopic data analyses and NMR comparison with known analogs, while those of 1, 2, 4 and 6 have been further supported by total synthesis, and it is the first report of this type of metabolites from the title species. All the isolates have been assessed in an array of bioassays encompassing cytotoxic, antibacterial, anti-inflammatory, antioxidant, as well as α-glucosidase and HDAC1 inhibitory models. Compound 7 showed significant inhibitory activity against α-glucosidase, and half of the isolates also displayed moderate antiradical effect.

Clerodane furanoditerpenoids from the stems of Tinospora sinensis.

One new clerodane-type furanoditerpenoid tinosinoid A (1) and nine new nor-clerodane analogs tinosinoids B-J (2-10) have been isolated from the stems of Tinospora sinensis. The structures of the new compounds with absolute configurations have been elucidated by spectroscopic means, including MS, NMR and ECD techniques, as well as chemical correlation. Compound 1 is a rare sulfur-containing clerodane diterpenoid incorporating a 2-mercaptoethanol unit via a thioether bond, while compounds 4/5 and 9 represent two pairs of unusual equilibrium regioisomers through an interesting intramolecular transesterification. Our bioassays established that 1 and 8 displayed moderate antiproliferative effects against two human tumor cell lines, and 9 and 10 showed significant α-glucosidase inhibitory activities. A kinetics study revealed that compound 10 was a noncompetitive α-glucosidase inhibitor, and its possible binding mode to the enzyme was further probed by molecular docking experiments.

Bis-Iridoids from Pterocephalus hookeri and Evaluation of Their Anti-Inflammatory Activity.

Four new secoiridoid-iridoid heterodimers, pterocenoids E-H (1-4), together with a known analog (5), were separated from the whole plants of Pterocephalus hookeri. Their structures were characterized by detailed spectroscopic analyses and NMR comparison with reported data for known analogs. Pterocenoid E (1) represents the first bis-iridoid example incorporating a rare trans-fused monomeric unit, and the C(8) configuration in 5 was corrected to be reversed to the original assignment. Among all the isolates, compound 5 not only showed moderate inhibition against the nitric oxide production (IC50 =36.0±4.3 µM) but also dose-dependently suppressed the secretion of an important pro-inflammatory cytokine TNF-α, in lipopolysaccharide-induced RAW264.7 cells.

Bioactive pentacyclic triterpenoids from the whole plants of Pterocephalus hookeri.

Eight undescribed triterpenoids (pterohoonoids A-H) including four oleananes, one nor-oleanane and three nor-ursanes, along with seven known analogues, were isolated from the whole plants of Pterocephalus hookeri (Dipsacaceae). The structures with relative stereochemistries of these molecules were elucidated mainly by spectroscopic analyses, and the absolute configurations of the undescribed ones were assigned by a variety of methods, including time-dependent density functional theory (TD-DFT) based electronic circular dichroism (ECD) calculation, Rh2(OCOCF3)4-induced ECD experiment and chemical transformation. The inhibitory effects toward the diabetes target α-glucosidase of all the isolates were assessed, and four of them exhibited pronounced activity with IC50 values ranging from 6.8 to 55.8 µM. In addition, four compounds also showed inhibition against the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 macrophage cells (IC50 = 12.4-63.7 µM). Further assays demonstrated that the most active compound pterohoonoid A inhibited the release of two key pro-inflammatory cytokines TNF-α and IL-6 in a dose-dependent manner.

21,24-Cyclolanostanes revisited: Structural revision and biological evaluation.

Chemical fractionation of the EtOH extract of a medicinal macro fungus, Inonotus obliquus, afforded an array of lanostane-type triterpenoids (1-11) including two new ones (1 and 8). The structures of these compounds were determined on the basis of spectroscopic analyses, single crystal X-ray crystallography of 3-6 and biosynthetic considerations. With the confirmatory structural information provided by X-ray diffraction analysis in hand, several previously reported 21,24-cyclolanostanes, such as inonotsutriols A-C and (20R,21S,24S)-21,24-cyclopenta-3ß,21,25-trihydroxylanosta-8-ene, were structurally corrected. In addition, the NMR data of other types of 21,24-cyclo triterpenoids were also re-examined and structural revisions were thus suggested. Compounds 2, 6 and 8 showed significant cytostatic effects against a panel of tumor cell lines with IC50 values ranging from 7.80 to 18.5 µM. Further assays established that compound 2 exerted promising in vitro anti-breast cancer potential by inhibiting the proliferation and migration of 4T1 cells.

A new tigliane-type diterpenoid from Euphorbia tirucalli.

Five tigliane (1-5) and one ingenane (6) diterpenoids were isolated from the ethanol extract of Euphorbia tirucalli. The structures of these compounds were identified based on analysis of their spectroscopic data. Among them, compound 12-O-(2E,4E,6E,8E-tetradecatetraenoyl)-13-O-isobutyroyl-4ß-deoxyphorbol (1) was a new tigliane. The Rho123 effluxion assay showed that tiglianes with a trans-fused 5/7 ring system such as compounds 1, 2, and 4 had potent inhibitory activity against P-glycoprotein in HepG2/ADR cells.

Diterpenoid glucosides with cystathionine γ-lyase inhibitory activity from Tinospora sinensis.

Fifteen previously undescribed nor-clerodane diterpenoid glucosides tinosinesides C-Q (1-15), along with four known analogues (16-19), were isolated from the stems of Tinospora sinensis. The structures of the new compounds were elucidated by spectroscopic means, and their absolute configurations were established on the basis of time-dependent density functional theory (TD-DFT) based electronic circular dichroism (ECD) calculation and chemical methods. All the isolates were evaluated for their inhibitory effects on cystathionine γ-lyase (CSE), a natural enzyme responsible for the synthesis of H2S. Compounds 4 and 5 represent rare examples of natural CSE inhibitors and the possible binding mode to CSE was further probed by molecular docking experiment.

Peritoneal Metastasis After Treated With Abemaciclib Plus Fulvestrant for Metastatic Invasive Lobular Breast Cancer: A Case Report and Review of the Literature.

Peritoneal metastases from invasive lobular carcinoma (ILC) of breast are uncommon and usually related to poor prognosis due to difficulty of detection in clinical practice and drug resistance. Therefore, recognizing the entities of peritoneal metastases of ILC and the potential mechanism of drug resistance is of great significance for early detection and providing accurate management. We herein report a case of a 60-year-old female who presented with nausea and vomiting as the first manifestation after treated with abemaciclib (a CDK4/6 inhibitor) plus fulvestrant for 23 months due to bone metastasis of ILC. Exploratory laparotomy found multiple nodules in the peritoneum and omentum, and immunohistochemistry confirmed that the peritoneal metastatic lesions were consistent with ILC. Palliative therapy was initiated, but the patient died two months later due to disease progression with malignant ascites. Whole exome sequencing (WES) was used to detect the tumor samples and showed the peritoneal metastatic lesions had acquired ESR1 and PI3KCA mutations, potentially explaining the mechanism of endocrine therapy resistance. We argue that early diagnosis of peritoneal metastasis from breast cancer is crucial for prompt and adequate treatment and WES might be an effective supplementary technique for detection of potential gene mutations and providing accurate treatment for metastatic breast cancer patients.

Lignans with NO inhibitory activity from Tinospora sinensis.

Two new lignan glucosides, tinsinlignans A and B (1 and 2), two new oxyneolignans, tinsinlignans C and D (3 and 4), along with one known analogue (5), were isolated from the stems of Tinospora sinensis. The structures of the new compounds were elucidated based on analysis of spectroscopic data, and the absolute configuration of 1 was determined through electronic circular dichroism (ECD) calculation based on the time-dependent density functional theory (TD-DFT). Compounds 1-4 were evaluated for their inhibitory effects on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in murine RAW264.7 macrophage cells and compounds 1 and 2 exhibited moderate inhibitory activities with IC50 values of 18.5 ± 2.0 and 28.8 ± 1.2 µmol·L-1, respectively.