New phenylbutenoids and terpene glycosides from Ginkgo biloba leaves.

Our continued works on the chemical constituents of Ginkgo biloba (G. biloba) leaves has led to the isolation of two novel phenylbutenoids (1, 2), along with five previously unidentified terpene glycosides (3-7). Among them, compounds 1 and 2 represent unique (Z)-phenylbutenoids, 3-6 are megastigmane glycosides, and 7 is identified as a rare bilobanone glycoside (Fig. 1). This study marks the first reported isolation of phenylbutenoid and bilobanone glycoside from G. biloba. The chemical structures of these compounds were elucidated through extensive spectroscopic analysis, including HR-ESI-MS and various 1D and 2D NMR experiments. Furthermore, the absolute configurations of these molecules were determined using Mosher's method, ECD experiments, and Cu-Kα X-ray crystallographic analyses.

A new bilobalide isomer and two cis-coumaroylated flavonol glycosides from Ginkgo biloba leaves.

A new bilobalide isomer (1), together with two flavonol glycosides (2, 3), have been isolated and elucidated from the extract of Ginkgo biloba leaves. Significantly, 1 was a new sesquiterpene lactone with two lactone ring groups, both 2 and 3 were two flavonol glycosides with a same cis-coumaroylated fragment. Their chemical structures were elucidated by NMR and MS spectroscopic date and the absolute configuration of 1 was specific established by Cu-Kα X-ray crystallographic analyses. However, 1-3 showed no obvious anti-platelet aggregation activity.

Lineariifolianoids M-O, three rare sesquiterpene lactone dimers inhibiting NO production from Inula lineariifolia.

Three rare squiterpene lactone dimers lineariifolianoids M-O (1-3) were isolated from Inula lineariifolia for the first time. Their structures and absolute configuration were established on the basis of by NMR and MS spectroscopic data and X-ray crystallography. Furthermore, those three compounds exhibited significant inhibitory activity against LPS-induced NO production in RAW 264.7 macrophages with IC50 values of 1.421, 1.087 and 1.243 µM, respectively.

Bilobetin induces kidney injury by influencing cGMP-mediated AQP-2 trafficking and podocyte cell cycle arrest.

BACKGROUND: Ginkgo biloba (Gb) extracts have been used as a traditional Chinese medicine. Gb contains flavonoids, which are considered to be its active ingredients and have been used in the treatment of a variety of diseases. However, few scientific research studies on the side effects of flavonoid in Gb have been reported. PURPOSE: The present study aimed to investigate the effect of bilobetin on the kidney of Sprague-Dawley (SD) rats. STUDY DESIGN AND RESULT: In this study, rats were injected with 50 mg/kg of bilobetin, a biflavone isolated from Gb, for 7 days and aristolochic acid was used as positive controls. The results showed that the body weight and urine output of the rats were dramatically decreased, and urinary protein increased after the intraperitoneal injection of bilobetin compared with the control group. Bilobetin treatment showed vacuolar degeneration in the renal tubular epithelium, glomerular atrophy by histostaining, and podocyte fusion by electron microscopy. This study further showed that bilobetin promoted the trafficking of aquaporin 2 (AQP-2) onto the plasma membrane to achieve the function of urine concentration by in vivo study in rats and in vitro study in IMCD-3 cells. The redistribution of AQP-2 is due to increased expression of cGMP in IMCD-3 cells, which in turn promoted the phosphorylation of AQP-2 at site Ser-256. The proteinuria caused by bilobetin may be attributed to podocyte cell cycle arrest at G2/M transition, which is may associated with AKT and MAPK signaling. CONCLUSIONS: The current study showed that bilobetin has some side effects on kidneys at a dose of 50 mg/kg in SD rats and provides insight into the potential detrimental effects of monomeric ingredients in Gb.

Vlasoulamine A, a Neuroprotective [3.2.2]Cyclazine Sesquiterpene Lactone Dimer from the Roots of Vladimiria souliei.

Vlasoulamine A (1), an unprecedented sesquiterpene lactone dimer featuring a fully hydrogenated pyrrolo[2,1,5- cd]indolizine core, and vlasoulones A and B (2 and 3), a pair of epimeric dimers formed from a proposed Diels-Alder [4 + 2] cycloaddition between a germacrane sesquiterpene lactone and a eudesmane sesquiterpene, were isolated from the roots of Vladimiria souliei. Their structures and absolute configurations were established by NMR, MS, and single-crystal X-ray spectroscopic analysis. Moreover, 1 exhibited neuroprotective activity when evaluated for glutamate-induced cytotoxicity, nuclear Hoechst 33258 staining, and measuring intracellular reactive oxygen species levels, using a rat pheochromocytoma PC12 cell-based model system.

Five rare dimeric sesquiterpenes exhibiting potential neuroprotection activity from Vladimiria souliei.

Two rare C32 sesquiterpene lactone dimers, vlasouliolides J-K (1-2), together with three C30 sesquiterpene dimers, vlasoulioliones A-C (3-5), were isolated from Vladimiria souliei. Their chemical structures were elucidated by NMR and MS spectroscopic data. Among them, compounds 1, 3 and 5 were unambiguously established by Cu-Kα X-ray crystallographic analysis. Furthermore, compound 1 showed prominent neuroprotective effects against glutamate-induced neurotoxicity in PC-12 cells, with EC50 value of 2.11 ±â€¯0.35 µM. And the leakage of LDH from glutamate-induced PC-12 was significantly reduced by compound 1 at concentration of 10 µM.

Five rare C32 sesquiterpene lactone dimers with anti-inflammation activity from Vladimiria souliei.

Five rare sesquiterpene lactone dimers, vlasouliolides E-I, were isolated from Vladimiria souliei. Their chemical structures were elucidated by spectroscopic analysis. Furthermore, 2 and 4 were unambiguously confirmed by Cu-Kα X-ray crystallographic analysis. Compounds 1, 2, 4 and 5 exhibited significant anti-inflammatory activity against LPS-induced NO production in RAW 264.7 cells with IC50 values of 1.88, 4.89, 7.24 and 2.46µM, respectively. Additionally, compounds 1 and 2 were revealed with potent inhibitory activity of the phosphorylation progress of NF-κB P65.

Chlorajaponols A-F, sesquiterpenoids from Chloranthus japonicus and their in vitro anti-inflammatory and anti-tumor activities.

Two new eudesmane sesquiterpenoids, chlorajaponols A-B (1-2), two new guaiane sesquiterpenoids, chlorajaponols C-D (3-4), a new germacrane sesquiterpenoid, chlorajaponol E (5), and a new lindenane sesquiterpenoid, chlorajaponol F (6), along with 8 known sesquiterpenoids and 6 known disesquiterpenoids, were isolated from the whole plant of Chloranthus japonicus. Their structures were established by extensive analysis of NMR spectroscopic data in combination with mass spectrometry. The structures of compounds 1-4 were confirmed by single crystal X-ray diffraction (CuKα radiation). The possible biogenetic pathways of compounds 1-6 were discussed. Chlorajaponol B (2) showed significant inhibition against nitric oxide (NO) release in LPS-induced RAW264.7 macrophages with the IC50 value of 9.56±0.71µM, comparable to that of positive control amino guanidine (8.50±0.35µM). Shizukaol C (18) strongly suppressed the proliferation of three human tumor cell lines MGC803, HepG2, and HL-60 with IC50 values of 4.60±1.05µM, 3.17±0.66µM, and 1.57±0.27µM, respectively.

[Relationship between cyclooxysenase 2 and serious hepatitis].

AIM: To study the cytokines regulated downstream effecter cyclooxygenase (COX-2's) function in the progression of serious hepatitis. METHODS: Samples from 75 patients with hepatitis B virus (HBV)-associated serious liver disease with well-characterised clincal profiles and 30 HBV-infected patients were assessed by ELISA. RESULTS: Compared with the general HBV-infected patients, serum TXB2 and 6-keto-PG1α level were uniformly elevated in all serious hepatitis patients (acute serious hepatitis patients vs general HBV-infected patients (P < 0.001); sub-acute serious hepatitis patients vs general HBV-infected patients (P < 0.01); chronic serious hepatitis patients vs general HBV-infected patients (P < 0.001). But there were no significant difference of these cytokines levels among the different types of serious hepatitis patients (P > 0.05). CONCLUSION: In conclusion, product of COX-2 metabolism TXB2 and 6-keto-PGF1α were associated with the clinical progression of serious hepatitis; especially TXB2/6-keto-PGF1α ratio is an effective biological marker for prognosis and diagnosis for serious hepatitis.