Highly Oxygenated Grayanane Diterpenoids from Flowers of Pieris japonica and Structure-Activity Relationships of Antifeedant Activity against Pieris brassicae.

Six new highly oxygenated grayanane diterpenoids, neopierisoids G-L, 1-6, together with 10 known related compounds, 7-16, were identified from the flowers of the poisonous plant Pieris japonica. The structures were elucidated on the basis of comprehensive NMR spectroscopy and mass analysis. The relative configurations of 1-6 were elucidated by analysis of ROESY spectra and comparison of NMR data with the analogues. The absolute configurations of 1-6 were established by the X-ray diffraction analysis of 1 and comparison of the CD spectra of 1-6. Compared with the skeleton of the normal grayanane diterpenoids, compounds 1-6 shared an unusual seco A ring moiety. The antifeedant activities of compounds 1-16 against Pieris brassicae were evaluated by using a dual-choice bioassay, and compounds 1-10 with a normal grayanane skeleton showed potent antifeedant activity against P. brassicae. The structure-activity relationships of antifeedant activities of 1-16 against P. brassicae are discussed.

Preventive and therapeutic effect of simvastatin on secondary inflammatory damage of rats with cerebral hemorrhage.

OBJECTIVE: To investigate the preventive and therapeutic effect and mechanism of simvastatin on secondary inflammatory damage of rats with cerebral hemorrhage. METHODS: Sixty SD rat aged 9-12 weeks were chosen and divided into the control group, model group and simvastatin-treated group randomly with 20 rats in each group. Rats in the model group and simvastatin-treated group were infused with autologous fresh uncoagulated blood to the right brain tissue of the basal ganglia to build the cerebral hemorrhage model, while rats in the control group were treated with the same amount of normal saline. Then, rats in the simvastatin-treated group were given a gavage of 3 mg/kg of simvastatin once a day after modeling. Rats in the three groups were given nerve dysfunction score (NDS) and wet-dry weighting method was used to detect the brain water content (BWC) of brain tissues around the lesion of the rats. Then Nissl staining was conducted and the undamaged neurons were counted. Immunohistochemical SP method was applied to count the number of NF-κB, TLR4 and IL-1ß positive cells in brain tissues around the lesions, and the immuno fluorescence method was employed to determine the expression levels of NF-κB, TLR4 and IL-1ß proteins. RESULTS: The NDS results of the simvastatin-treated group at all time points were all significantly higher than those of the model group (P < 0.05); the BWC values of the simvastatin-treated group at all time points were all significantly lower than those of the model group at the same periods (P < 0.05); the number of the undamaged neurons around the lesions of the simvastatin-treated group at all time points were all significantly higher than those of the model group (P < 0.05); seven days after treatment, the number of the NF-κB, TLR4 and IL-1ß positive cells in brain tissues around the lesions of the simvastatin-treated group were all significantly lower than those of the model group (P < 0.05), and its expression levels of NF-κB, TLR4 and IL-1ß protein were also significantly lower than those of the model group (P < 0.05). CONCLUSIONS: Simvastatin can inhibit the expressions of NF-κB, TLR4 and IL-1ß proteins in rats with cerebral hemorrhage, and protect neurons and reduce secondary inflammatory damages by down-regulating the above protein-mediated inflammatory responses.

Antioxidant lignans from the seeds of Vitex negundo var. cannabifolia.

A new phenyldihydronaphthalene-type lignan, vitexdoin F (1), along with 22 known lignan derivatives (2-23) was isolated from the seeds of Vitex negundo var. cannabifolia. Their structures were established by comprehensive 1D and 2D NMR spectroscopic analyses. The antioxidant activities of these lignans were evaluated through 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assays, and 16 of these isolates exhibited obvious radical-scavenging effect on the stable-free radical, DPPH.

Neopierisoids A and B, two new chlorinated 3,4-seco-grayanane diterpenoids with antifeedant activity from flowers of Pieris japonica.

Two new chlorinated multiacylated 3,4-seco-grayanane diterpenoids, neopierisoids A and B (1 and 2), were isolated from flowers of the poisonous plant Pieris japonica and were identified from spectroscopic analysis and X-ray diffraction data. Both compounds showed obvious antifeedant activity against Pieris brassicae with an EC50 of 10.07 µg/cm(2) for 1 and 5.33 µg/cm(2) for 2, indications of toxic properties. Chlorinated 3,4-seco-grayanane diterpenoids in P. japonica may play a defensive role against herbivores.