Lycodine-type alkaloids from Lycopodiastrum casuarinoides and their acetylcholinesterase inhibitory activity.

Five previously undescribed lycodine-type alkaloids, named huperzine Y (1), 8,15-epoxy-N-demethylhuperzinine (2), 7-hydroxyl-huperzinine (3), huperzine Z (4), and huperzine D N-oxide (5), were isolated from the aerial parts and roots of Lycopodiastrum casuarinoides (Lycopodiaceae), along with ten known analogues. The structures of the new compounds were elucidated by means of spectroscopic technique (IR, UV, MS and NMR). The absolute configurations of the new compounds were established on the basis of comparison of their experimental and TD-DFT (time-dependent density functional theory) calculated ECD spectra. Moreover, all the isolates were evaluated for acetylcholinesterase (AChE) inhibitory activity. Only huperzine C showed moderate activity, with an IC50 value of 0.525 ±â€¯0.140 µM, which was comparable with the positive control, huperzine A (IC50 = 0.143 ±â€¯0.029 µM).

Benzofurans from Eupatorium chinense enhance insulin-stimulated glucose uptake in C2C12 myotubes and suppress inflammatory response in RAW264.7 macrophages.

Fourteen acetylbenzofuran derivatives, including three undescribed carbon skeletons with a newly formed hexane or benzene ring on the other side of the benzofuran ring, (±)-eupatonin A (1), (±)-eupatonin B (2), and eupatonin C (3), two new benzofurans (-)-12ß-hydroxygynunone (4) and (+)-12-hydroxyl-13-noreuparin (5), as well as 9 known ones (6-14), were isolated from 95% ethanol extract of the roots of Eupatorium chinense. Their structures were determined by spectroscopic methods and quantum chemical DFT and TDDFT calculations of the NMR chemical shifts and ECD spectra, which helped in the determination of the relative configurations of 1 and 2 and the absolute configurations of 4 and 5, respectively. 1 and 2 were further identified to be racemic mixtures by chiral HPLC analysis. All compounds were evaluated for insulin-stimulated glucose uptake in differentiated C2C12 myotubes. Compounds 1, 3, 4, 5, 11, 12, and 13 markedly enhanced insulin-mediated glucose uptake. (±)-Eupatonin A (1) activated the IRS-1/Akt/GSK-3ß signaling pathway and enhanced insulin stimulated GLUT4 membrane translocation in C2C12 myotubes. On LPS stimulated RAW264.7 macrophages, several compounds exhibited significant inhibitory effect on NO production with IC50 values ranging from 4.94 to 9.70 µΜ. (±)-Eupatonin A (1) again dose-dependently suppressed LPS-induced NO production and decreased the expression of inducible NO synthase (iNOS), through inhibiting NF-κB activity.

[Effect of electroacupuncture on nitric oxide synthase in rats with cerebral ischemia-reperfusion injury].

OBJECTIVE: To study the effect of electroacupuncture on nitric oxide synthase (NOS) in rats with cerebral ischemia-reperfusion injury. METHODS: Focal cerebral ischemia-reperfusion model was established using modified intravascular suture technique. The NO content in the brain tissue was detected by nitrite reduction and the expressions of nNOS and iNOS were detected by immunohistochemistry. Eighty rats in this experiment were divided into the normal group, the cerebral ischemia-reperfusion injury model group (as the model group), the cerebral ischemia-reperfusion injury + electroacupuncture group (as the acupuncture group), and the cerebral ischemia-reperfusion injury + phosphatidylinositol 3 kinase (PI3-K) inhibitor group (as the inhibitor group). Each group consisted of twenty rats. Five microL PI3-K inhibitor LY294002 (400 microL) was slowly injected at the lateral cerebral ventricle of rats in the inhibitor group at a constant speed using microinjector according to Konig Klippel atlas of the stereotaxis instrument. Shuigou (DU26) and Chengjiang (RN24) were selected to determine levels of NO and NOS. RESULTS: After 24-h ischemia-reperfusion, the NO levels of the hippocampus and the cerebral cortex increased abnormally, and the expressions of nNOS and iNOS increased, showing significant difference when compared with those of the normal group (P<0.05). By electroacupuncture at Shuigou (DU26) and Chengjiang (RN24), the ischemic cerebral ischemia-reperfusion injury neuron loss was inhibited. Meanwhile, the high levels of NO, nNOS and iNOS in the cerebral cortex and the hippocampus were significantly inhibited (P<0.05). The abnormally increased expressions of nNOS and iNOS were reversed, showing significant difference when compared with the model group (P<0.05). But when compared with the normal group, there was no significant difference (P>0.05). The effects of electroacupuncture reversed the abnormally increased NO levels of the hippocampus and the cerebral cortex and expressions of nNOS and iNOS after LY294002 oppressed anti-PI3K to block the TrkA acceptor circuit. The NO levels of the hippocampus and the cerebral cortex and expressions of nNOS and iNOS increased again, showing significant difference when compared with the acupuncture group (P<0.05). CONCLUSIONS: Acupuncture fought against cerebral ischemia and reperfusion in the loss of neurons, at the same time, the abnormal regulation of NOS had reverse effect partly through TrkA/PI3K mediated signal transduction pathway.

The effect of Ginkgo Biloba extract on the expression of PKCalpha in the inflammatory cells and the level of IL-5 in induced sputum of asthmatic patients.

To investigate the effect of the Ginkgo Biloba Extract (GBE) on the asthma and examine its possible mechanisms, 75 asthma patients were divided into 4 groups and the patients were respectively treated with fluticasone propionate for 2 weeks or 4 weeks, or treated with fluticasone propionate plus GBE for 2 weeks or 4 weeks. Fifteen healthy volunteers served as healthy controls. Sputum inhalation with inhaling hypertonic saline (4%-5%) was performed. Lung ventilatory function and forced expiratory volume in one second (FEV1) were measured. The numbers of different cells in induced sputum were calculated. The expression of PKCalpha in the cells was immunocytochemically detected and the percentages of positive cells in different cells were counted. Interleukin-5 (IL-5) in sputum supernatants was detected with enzyme-linked immunosorbent assay. The percentage of eosinophils, lymphocytes, PKCalpha positive inflammatory cells and the concentration of IL-5 in asthmatic patients were higher than those in the controls (P<0.05), and the eosinophils, lymphocytes, positive expression of PKCalpha and the level of IL-5 were significantly decreased in asthmatic patients after they were treated with fluticasone propionate or fluticasone propionate plus GBE. However, they were still significantly higher than those of the controls. Compared to the group treated with glucocorticosteroid for 2 weeks, no significant decrease was found in the percentage of eosinophils, lymphocytes, PKCalpha positive inflammatory cells and the IL-5 in the supernatant of induced sputum. Compared with the group treated with glucocorticosteroid for 2 or 4 weeks, significant decrease in the same parameters was observed in the group treated with fluticasone propionate and GBE for 4 weeks. The IL-5 level in the supernatant of induced sputum was positively correlated with the percentage of PKCalpha-positive inflammatory cells and the percentage of eosinophils in the induced sputum in asthma patient groups respectively (n=150, r= 0.83, P<0.01; n=150, r=0.76, P<0.01). The FEV1 was negatively correlated with the percentage of PKCalpha-positive inflammatory cells and the IL-5 levels in supernatant of induced sputum in asthma patients respectively (n=150, r=-0.77, P<0.01; n=150, r= -0.64, P<0.01). It is concluded that GBE could significantly decrease the infiltration of inflammatory cells such as eosinophils and lymphocytes in the asthmatic airway and relieve the airway inflammation. GBE may decrease the activation of the PKCalpha in the inflammatory cells and thereby decrease the IL-5 level in induced sputum. GBE may be used as a complement to the glucocorticosteroid therapy for asthma.