Uric acid-lowering effect of harpagoside and its protective effect against hyperuricemia-induced renal injury in mice.

Hyperuricemia (HUA) is caused by increased synthesis and/or insufficient excretion of uric acid (UA). Long-lasting HUA may lead to a number of diseases including gout and kidney injury. Harpagoside (Harp) is a bioactive compound with potent anti-inflammatory activity from the roots of Scrophularia ningpoensis. Nevertheless, its potential effect on HUA was not reported. The anti-HUA and nephroprotective effects of Harp on HUA mice were assessed by biochemical and histological analysis. The proteins responsible for UA production and transportation were investigated to figure out its anti-HUA mechanism, while proteins related to NF-κB/NLRP3 pathway were evaluated to reveal its nephroprotective mechanism. The safety was evaluated by testing its effect on body weight and organ coefficients. The results showed that Harp significantly reduced the SUA level and protected the kidney against HUA-induced injury but had no negative effect on safety. Mechanistically, Harp significantly reduced UA production by acting as inhibitors of xanthine oxidase (XOD) and adenosine deaminase (ADA) and decreased UA excretion by acting as activators of ABCG2, OAT1 and inhibitors of GLUT9 and URAT1. Moreover, Harp markedly reduced infiltration of inflammatory cells and down-regulated expressions of TNF-α, NF-κB, NLRP3 and IL-1ß in the kidney. Harp was a promising anti-HUA agent.

Phomopsterone B Alleviates Liver Fibrosis through mTOR-Mediated Autophagy and Apoptosis Pathway.

Liver fibrosis is the initial pathological process of many chronic liver diseases. Targeting hepatic stellate cell (HSC) activation is an available strategy for the therapy of liver fibrosis. We aimed to explore the anti-liver fibrosis activity and potential mechanism of phomopsterone B (PB) in human HSCs. The results showed that PB effectively attenuated the proliferation of TGF-ß1-stimulated LX-2 cells in a concentration-dependent manner at doses of 1, 2, and 4 µM. Quantitative real-time PCR and Western blot assays displayed that PB significantly reduced the expression levels of α-SMA and collagen I/III. AO/EB and Hoechst33342 staining and flow cytometry assays exhibited that PB promoted the cells' apoptosis. Meanwhile, PB diminished the number of autophagic vesicles and vacuolated structures, and the LC3B fluorescent spots indicated that PB could effectively inhibit the accretion of autophagosomes in LX-2 cells. Moreover, rapamycin and MHY1485 were utilized to further investigate the effect of mTOR in autophagy and apoptosis. The results demonstrated that PB regulated autophagy and apoptosis via the mTOR-dependent pathway in LX-2 cells. In summary, this is the first evidence that PB effectively alleviates liver fibrosis in TGF-ß1-stimulated LX-2 cells, and PB may be a promising candidate for the prevention of liver fibrosis.

Three New Selaginellin Derivatives from Selaginella pulvinata and Their α-Glucosidase Inhibitory Activity.

Three new selaginellin derivatives, selaginpulvilins V-X (1-3), together with seven known analogs (4-10) were isolated from whole plants of Selaginella pulvinata. Their structures were determined by extensive spectroscopic methods including 1D and 2D NMR, HR-ESI-MS and chemical derivatization method. Compound 1 represents a rare example of naturally occurring selaginellin with an alkynylphenol-trimmed skeleton. Biological evaluation showed that compounds 2, 6 and 8 displayed moderate inhibition against α-glucosidase with IC50 values of 3.71, 2.04 and 4.00 µM, respectively.

Hupertimines A-E, Fawcettimine-Type Lycopodium Alkaloids from Huperzia serrata.

Five new fawcettimine-type Lycopodium alkaloids, hupertimines A-E (1-5), were discovered from the whole plant of Huperzia serrata, along with two known alkaloids, 8α-hydroxyphlegmariurine B (6) and 8ß-hydroxyphlegmariurine B (7). The structures of 1-7 were identified through HR-MS, IR, 1 H, 13 C, and 2D NMR, and single-crystal X-ray diffraction analysis. Structurally, compound 1 was the fourth example of Lycopodium alkaloid with an ether linkage between C-5 and C-13 and 2 was the third example of Lycopodium alkaloid with a 5/5/5/5/6 pentacyclic ring system and featuring a 1-aza-7-oxabicyclo[2.2.1]heptane unit. Compounds 1-7 were tested for their BACE1 inhibitory activity. In addition, the correct 1 H- and 13 C-NMR data for 7 were reported in current study.

Ent-Abietane Diterpenoids from Euphorbia fischeriana and Their Cytotoxic Activities.

The roots of Euphorbia fischeriana have been used as a traditional Chinese medicine for the treatment of tuberculosis and ringworm. In the current study, diterpenoids from the ethyl acetate extract of the roots E. fischeriana and their cytotoxic effects against five cancer lines were investigated. Two new ent-abietane diterpenoids, euphonoids H and I (1-2), as well as their two analogues (3-4) were first isolated from this source. The structures of the two new compounds were elucidated on the basis of spectroscopic data and quantum chemical calculation. Their absolute configurations were assigned via ECD spectrum calculation. The isolated compounds were evaluated for their antiproliferative activities against five cancer cell lines. Compounds 1 and 2 exhibited significant inhibitory effects against human prostate cancers C4-2B and C4-2B/ENZR cell lines with IC50 values ranging from 4.16 ± 0.42 to 5.74 ± 0.45 µM.

New Meroterpenoid and Isocoumarins from the Fungus Talaromyces amestolkiae MST1-15 Collected from Coal Area.

Three new compounds including a meroterpenoid (1) and two isocoumarins (8 and 9), together with thirteen known compounds (2-7, 10-16) were isolated from the metabolites of Talaromyces amestolkiae MST1-15. Their structures were identified by a combination of spectroscopic analysis. The absolute configuration of compound 1 was elucidated on the basis of experimental and electronic circular dichroism calculation, and compounds 8 and 9 were determined by Mo2(OAc)4-induced circular dichroism experiments. Compounds 7-16 showed weak antibacterial activities against Stenotrophomonas maltophilia with MIC values ranging from 128 to 512 µg/mL (MICs of ceftriaxone sodium and levofloxacin were 128 and 0.25 µg/mL, respectively).

Presegetane diterpenoids from Euphorbia sieboldiana as a new type of anti-liver fibrosis agents that inhibit TGF-ß/Smad signaling pathway.

Seven new diterpenoids, eupholenes A-G (1-7), including two presegetanes (1 and 2), four jatrophanes (3-6), and one paraliane (7), along with 19 known analogues (8-26) were obtained by anti-liver fibrosis bioassay-guided isolation of Euphorbia sieboldiana. Their structures were elucidated by extensive spectroscopic data analyses, chemical methods, ECD calculations, and single-crystal X-ray diffractions. Euphorbesulin A (10), a presegetane diterpenoid (5/9/5 ring system), was identified as a promising anti-liver fibrosis agent that could inhibit the expressions of fibronectin (FN), α-smooth muscle actin (α-SMA), and collagen I in TGF-ß1-stimulated LX-2 cells at a micromolar level. Mechanistic study revealed that 10 suppressed liver fibrosis via inhibition of TGF-ß/Smad signaling pathway, and its potential target was TGF-ß type I receptor. These findings suggested that presegetane diterpenoid could serve as a new type of structural motif in future anti-liver fibrosis drug development.

Pseudosterins A-C, Three 1-Ethyl-3-formyl-ß-carbolines from Pseudostellaria heterophylla and Their Cardioprotective Effects.

Pseudostellaria heterophylla is used in China not only as a functional food but also as an herb to tonify the spleen, enhance immunity, and treat palpitation. Our previous investigation showed that a fraction enriched in glycosides obtained from the roots of P. heterophylla possessed pronounced protective effects on H9c2 cells against CoCl2-induced hypoxic injury. However, the active compounds responsible for the observed effects were still unknown. In the current investigation, pseudosterins A-C (1-3), three new alkaloids with a 1-ethyl-3-formyl-ß-carboline skeleton, together with polydatin, have been isolated from the active fraction. Their structures were elucidated on the basis of spectroscopic analysis and quantum chemical calculations. The four compounds showed cardioprotective effects against sodium hydrosulfite-induced hypoxia-reoxygenation injury in H9c2 cells, with the three alkaloids being more potent. This is also the first report of alkaloids with a ß-carboline skeleton isolated from P. heterophylla as cardioprotective agents.

Three new Lycopodium alkaloids from Lycopodium japonicum.

Three new Lycopodium alkaloids (1-3), together with 15 known alkaloids, were isolated from club moss Lycopodium japonicum. Their structures were determined by extensive spectroscopic analysis, including 1D and 2D NMR spectra. Compound 1 has an unusual ß-oriented methyl group substituted at C-15 and an α-hydroxy cyclopentenone moiety. All new alkaloids were evaluated for the inhibition of T-type calcium channel.

Vibsane-Type Diterpenoids from Viburnum odoratissimum and Their Cytotoxic and HSP90 Inhibitory Activities.

Four new vibsane-type diterpenoids, vibsanol I (1), 15-hydroperoxyvibsanol A (2), 14-hydroperoxyvibsanol B (3), 15-O-methylvibsanin U (4), and a new natural product, 5,6-dihydrovibsanin B (5), as well as six known analogues, were isolated from the twigs and leaves of Viburnum odoratissimum. Their structures were elucidated by spectroscopic analyses and chemical derivatization method. All compounds showed different levels of cytotoxicity against five cell lines (HL-60, A-549, SMMC-7721, MCF-7, and SW480). Remarkably, 14,18-O-diacetyl-15-O-methylvibsanin U (4a) showed significant cytotoxicity against HL-60, A-549, SMMC-7721, MCF-7, and SW480, with IC50 values of 0.15 ± 0.01, 0.69 ± 0.01, 0.41 ± 0.02, 0.75 ± 0.03, and 0.48 ± 0.03 µm, respectively. In addition, vibsanin K (10) was identified as a HSP90 inhibitor with an IC50 value of 19.16 µm.

Hypoxia inducible factor 2 alpha inhibits hepatocellular carcinoma growth through the transcription factor dimerization partner 3/ E2F transcription factor 1-dependent apoptotic pathway.

UNLABELLED: Hypoxia inducible factors (HIFs) are activated in many tumors and show either promoter or suppressor activity, depending on tumor cell biology and background. However, the role of HIF member HIF-2α remains unclear in hepatocellular carcinoma (HCC). Here, HIF-2α expression was measured in HCC and paired peritumoral tissues by quantitative real-time polymerase chain reaction, western blotting, and immunofluorescence assays, and the clinical significance was explored in 246 HCC patients. In cell culture, HIF-2α levels were up-regulated or down-regulated by use of expression or short hairpin RNA recombinant plasmid, respectively. Cells were analyzed by immunoblotting, chromatin immunoprecipitation coupled with microarray, coimmunoprecipitation, and immunohistochemical staining. In vivo tumor growth was analyzed in nude mice. We found that the average expression of HIF-2α was relatively low in HCC tissues, and the decreased level was associated with lower overall survival (P=0.006). High HIF-2α expression in HCC cells induced higher levels of apoptosis and expression of proapoptotic proteins and inhibited cell and tumor growth. Furthermore, HIF-2α inhibited expression of the novel target gene, transcription factor dimerization partner 3 (TFDP3). TFDP3 protein was found to bind with E2F transcription factor 1 (E2F1) and inhibit its transcriptional activity through both p53-dependent and -independent pathways. Reintroduction of TFDP3 expression reversed HIF-2α-induced apoptosis. CONCLUSIONS: Data gathered from cell lines, tumorigenicity studies, and primary HCC samples demonstrate a negative role of HIF-2α in tumors, which is mediated by the TFDP3/E2F1 pathway. Our study provides evidence supporting a possible tumor-suppressor role for HIF-2α and has uncovered a mechanism that links HIF-2α to a fundamental biological regulator, E2F1.

Two new withanolides from Physalis minima L.

Two new withanolides named physaminilides L (1) and M (2), together with four known ones (3-6) were isolated from the Physalis minima L. The structures were established by analysis of the HR ESIMS, IR and NMR spectroscopic data. The absolute configurations were determined through NOESY and ECD spectra. For compounds 1-5 assayed at 20 µM and compound 6 at 10 µM, inhibition rates of hepatic fibrosis were 22.19%, 15.29%, 37.07%, 9.27%, 12.45%, and 37.03%, respectively.

Withanolides from the active extract of Physalis angulate and their anti-hepatic fibrosis effects.

ETHNOPHARMACOLOGICAL RELEVANCE: Physalis angulata L., a traditional Chinese medicine called "Kuzhi" in China, was used traditionally to treat liver diseases (eg. icterus, hepatitis) as well as malaria, asthma, and rheumatism. AIM OF THE STUDY: Our study aimed to investigate the withanolides with anti-hepatic fibrosis effect from P. angulate. MATERIALS AND METHODS: Withanolides were obtained from the EtOH extract of P. angulate by bioassay-molecular networking analysis-guided isolation using column chromatography and normal/reversed-phase semipreparative HPLC. The structures of new withanolides were elucidated by combinations of spectroscopic techniques with NMR and ECD calculations. MTT cell viability assay, AO/EB staining method, cell wound healing assay, ELISA and Western blot experiments were employed to evaluate the anti-hepatic fibrosis activity and to uncover related mechanism. Molecular docking analysis and cellular thermal shift assay were used to evaluate and verify the interaction between the active withanolides and their potential targets. RESULTS: Eight unreported withanolides, withagulides A-H (1-8), along with twenty-eight known ones were obtained from P. angulate. Withanolides 6, 9, 10, 24, 27, and 29-32 showed marked anti-hepatic fibrosis effect with COL1A1 expression inhibition above 50 %. Physalin F (9), the main component in the active fraction, significantly decreased the TGF ß1-stimulated expressions of collagen I and α-SMA in LX-2 cells. Mechanism study revealed that physalin F exerted its anti-hepatic fibrosis effect via the PI3K/AKT/mTOR signaling pathway. CONCLUSION: This study suggested that withanolides were an important class of natural products with marked anti-hepatic fibrosis effect. The main withanolide physalin F might be a promising candidate for hepatic fibrosis treatment. The work provided experimental foundation for the use of P. angulate to treat hepatic fibrosis.

A new phenolic compound from Persicaria capitata.

Persicaria capitata was a frequently used Hmong medicinal flora in China. In this study, one new phenolic compound, capitaone A (1) together with 20 known ones, were isolated from the whole herb of P. capitata. Among them, 7 components (4, 9-11, 15-16, 20-21) were discovered from P. capitata for the first time. Their chemical structures were elucidated on the basis of extensive NMR and MS spectrum. Furthermore, three compounds (15, 20, 21) displayed remarkable cytotoxic activities against two human cancer cell lines (A549 and HepG2).

Chemical constituents of Aspergillus udagawae isolated from the soil of the Xingren coal areas and their antibacterial activities.

A new helvolic acid derivative (1), together with nine known compounds (2-10) were isolated from the metabolites of Aspergillus udagawae MST1-10 with the bioassay-guided fractionation method. Their structures were identified on the basis of spectroscopic analysis. The absolute configuration of compound 1 was elucidated through NOESY and ECD spectra. Compound 2 displayed significant antibacterial activities against Stenotrophomonas maltophilia with MIC value of 2 µg/mL (Trimethoprim, MIC = 64 µg/mL), and with biofilm inhibition rates of 96.41%, 87.77%, and 41.70% at 4MIC, 2MIC, and MIC, respectively.

Amelioration effects of α-viniferin on hyperuricemia and hyperuricemia-induced kidney injury in mice.

BACKGROUND: α-Viniferin, the major constituent of the roots of Caragana sinica (Buc'hoz) Rehder with a trimeric resveratrol oligostilbenoid skeleton, was demonstrated to possess a strong inhibitory effect on xanthine oxidase in vitro, suggesting it to be a potential anti-hyperuricemia agent. However, the in vivo anti-hyperuricemia effect and its underlying mechanism were still unknown. PURPOSE: The current study aimed to evaluate the anti-hyperuricemia effect of α-viniferin in a mouse model and to assess its safety profile with emphasis on its protective effect on hyperuricemia-induced renal injury. METHODS: The effects were assessed in a potassium oxonate (PO)- and hypoxanthine (HX)-induced hyperuricemia mice model by analyzing the levels of serum uric acid (SUA), urine uric acid (UUA), serum creatinine (SCRE), serum urea nitrogen (SBUN), and histological changes. Western blotting and transcriptomic analysis were used to identify the genes, proteins, and signaling pathways involved. RESULTS: α-Viniferin treatment significantly reduced SUA levels and markedly mitigated hyperuricemia-induced kidney injury in the hyperuricemia mice. Besides, α-viniferin did not show any obvious toxicity in mice. Research into the mechanism of action of α-viniferin revealed that it not only inhibited uric acid formation by acting as an XOD inhibitor, but also reduced uric acid absorption by acting as a GLUT9 and URAT1 dual inhibitor as well as promoted uric acid excretion by acting as a ABCG2 and OAT1 dual activator. Then, 54 differentially expressed (log2 FPKM ≥ 1.5, p ≤ 0.01) genes (DEGs) repressed by the treatment of α-viniferin in the hyperuricemia mice were identified in the kidney. Finally, gene annotation results revealed that downregulation of S100A9 in the IL-17 pathway, of CCR5 and PIK3R5 in the chemokine signaling pathway, and of TLR2, ITGA4, and PIK3R5 in the PI3K-AKT signaling pathway were involved in the protective effect of α-viniferin on the hyperuricemia-induced renal injury. CONCLUSIONS: α-Viniferin inhibited the production of uric acid through down-regulation of XOD in hyperuricemia mice. Besides, it also down-regulated the expressions of URAT1 and GLUT9 and up-regulated the expressions of ABCG2 and OAT1 to promote the excretion of uric acid. α-Viniferin could prevent hyperuricemia mice from renal damage by regulating the IL-17, chemokine, and PI3K-AKT signaling pathways. Collectively, α-viniferin was a promising antihyperuricemia agent with desirable safety profile. This is the first report of α-viniferin as an antihyperuricemia agent.

An unusual indole-diterpenoid with C-17 norcassane skeleton from Euphorbia fischeriana induces HEL cell cycle arrest and apoptosis.

Two new polycyclic diterpenoids, euphkanoids H and I (1 and 2), along with 6 known analogues (2-8) were isolated from the roots of Euphorbia fischeriana, a traditional Chinese medicine. Their structures were identified by spectral methods, and the absolute configurations of 1 and 2 were determined by ECD calculation and single crystal X-ray diffraction, respectively. Compound 1 represents the first example of C-17 norcassane indole-diterpenes. All the isolates were screened for antiproliferative activity against a panel of human cancer cell lines using the MTT assay, and 1 showed significant cytotoxicity against HEL cells (IC50 = 3.2 µM). Simple mechanistic study revealed that 1 could induce cell cycle arrest at G0/G1 phase and apoptosis in HEL cells.

Antibacterial activities of the chemical constituents of Schizophyllum commune MST7-3 collected from coal area.

Two fusidane-type active compounds (6 and 7) and five new ones (1-5), along with other nine known compounds (8-16) were isolated from the metabolites of Schizophyllum commune MST7-3. Their structures were elucidated on the basis of spectroscopic analysis. The absolute configurations of compounds 2 and 3 were established by Mosher's method and optical rotation. Compounds 6 and 7 showed significant antibacterial activities against Stenotrophomonas maltophilia with MIC values of 4 µg/mL and 16 µg/mL, respectively.

Euphorboside A, a cytotoxic meroterpenoid glycoside with an unusual humulene-phloroglucinol skeleton from Euphorbia kansuensis.

Euphorboside A (1), an unusual meroterpenoid glycoside featuring the incorporation of an acylphloroglucinol moiety into a humulene skeleton to form a 6/6/11 ring system, was isolated from the roots of Euphorbia kansuensis. Its structure was elucidated by extensive spectroscopic analysis, chemical methods, and ECD calculations. Compound 1 was screened for the cytotoxicity against nine cancer cell lines, and 1 showed marked inhibitory activities against human colon cancer RKO and human breast cancer MDA-MB-231 cell lines with IC50 values of 3.70 and 4.15 µM, respectively.

Clerodane-type Diterpene Glycosides from Dicranopteris pedata.

Three new clerodane-type diterpene glycosides, (5R,6S,8R,9S,10R)-6-O-[ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl]cleroda-3,13(16),14-diene (1), (5R,6S,8R,9S,10R,13S)-6-O-[ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl]-2-ox-oneocleroda-3,13-dien-15-ol (2), (5R,6S,8R,9S,10R)-6-O-[ß-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl]-(13E)-2-oxoneocleroda-3,14-dien-13-ol (3), together with two known compounds 4 and 5 were isolated from Dicranopteris pedata. The structures of these compounds were elucidated by detailed spectroscopic analysis, and the absolute configuration of compound 2 was determined by ECD calculations. In addition, compound 1 exhibited weak inhibitory activities against SMMC-7721, MCF-7 and SW480.