Novel nortriterpenoids with new skeletons and limonoids from the fruits of Evodia rutaecarpa and their bioactivities.

Two novel nortriterpenoids together with 7 known compounds were isolated from the fruits of Evodia rutaecarpa. The structures of the new compounds were elucidated by spectroscopic analysis, X-ray, and electronic circular dichroism (ECD) calculations. Compound 1 is the first example of triterpenoid with a 27 (17 â†’ 12)-abeo-five-ring skeleton. In turn, compound 2 possesses a unique C/D/E linear fused ring system and a methyl on C-21. Plausible biogenetic pathway for the new compounds 1 and 2 are also proposed. Compound 1 exhibited significantly antitumor activity against A549 and LoVo cells with IC50 values of 2.0 µM and 1.9 µM, respectively. Colony formation inhibition, cell cycle arrest and cell apoptosis of compound 1 were also evaluated. Compound 2, 6, 7 and 9 showed potent neuroprotective activities against serum-deprivation induced P12 cell damage.

[Grassland vegetation phenology change and its response to climate changes in North China]. / ä¸­å›½åŒ—æ–¹è‰åœ°æ¤è¢«ç‰©å€™å˜åŒ–åŠå ¶å¯¹æ°”å€™å˜åŒ–çš„å“åº”.

Understanding phenological change of grasslands has scientific significance to reveal their responses to global climate change. Based on the data of GIMMS NDVI 3g, climate data from 1983 to 2015 and digital elevation model (DEM), dynamic threshold method was used to extract the phenological information of northern grassland [the start of growth season (SOS), the end of growth season (EOS), and the length of growth season (LOS)]. We analyzed the temporal and spatial variation of phenology of grassland vegetation and the influence of climate on LOS. The results showed that 88.9% of SOS occurred from late March to late May (90-150 d), and 68.1% of pixels were advanced with a rate of -1.5-0 d·(32 a)-1. 79.7% of EOS occurred from early October to late October (270-300 d), with a delay rate of 0-1.5 d·(32 a)-1, accounting for 70.3% of the pixel number. LOS lasted for 100-140 days and became longer (73.7%), with a rate of 0-1.5 d·(32 a)-1. LOS was significantly positively correlated with temperature (R=0.628) and weakly negatively correlated with precipitation (R=-0.091). There was a significant spatial variation. The 2000 m line above sea level was recognized as the demarcation line. LOS had a weak positive correlation with altitude under 2000 m (R=0.235) and a significant negative correlation with altitude above 2000 m (R=-0.861). Above 3000 m altitude, LOS decreased by about 10 d for every 1000 m elevation.

Nomilin protects against cerebral ischemia-reperfusion induced neurological deficits and blood-brain barrier disruption via the Nrf2 pathway.

Oxidative stress is considered to play an important role in the cerebral ischemia-reperfusion injury. The nuclear transcription factor erythroid-2-related factor 2 (Nrf2)/NAD(P)H dehydrogenase [quinone] 1 (NQO1) pathway has been considered as a potential target for neuroprotection in cerebral ischemia-reperfusion injury. Nomilin (NOM) is a limonoid compound obtained from the extracts of citrus fruits. The purpose of our study was to determine whether NOM could exert beneficial effects in cerebral ischemia-reperfusion rats. Firstly, NOM treatment significantly mitigated cell death and decreased lactate dehydrogenase (LDH) release and ROS production in SH-SY5Y cells induced by oxygen-glucose deprivation (OGD), which was almost abolished by Nrf2 knockdown. Secondly, NOM improved infarct area, brain edema and neurological deficits in an experimental stroke rat model via middle cerebral artery occlusion (MCAO). Furthermore, NOM attenuated blood-brain barrier (BBB) disruption in MCAO rats, which might be associated with alleviating the loss of tight junction proteins, including ZO-1 and occludin-5. Further results revealed that NOM treatment effectively mitigated oxidative stress and facilitated the expressions of Nrf2 and NQO1, which might confirm that the loss of tight junction proteins in the microvasculature was likely mediated by oxidative stress. In conclusion, our study provided evidence that the protective effects of NOM in cerebral ischemia-reperfusion rats were related to the Nrf2/NQO1 pathway.

Fisetin Attenuates Metabolic Dysfunction in Mice Challenged with a High-Fructose Diet.

Excess fructose consumption can lead to metabolic syndrome, including insulin resistance, dyslipidemia, and hepatic injury, which are associated with oxidative stress and inflammation. The present study was to investigate whether fisetin improved multiple disturbances induced by fructose consumption. First, fisetin was found to be nontoxic to mice after an 8 week treatment. Second, the mice fed with a high-fructose (HFru)-diet for 8 weeks exhibited insulin resistance, dyslipidemia, hepatic injury, oxidative stress, and inflammation. Fisetin supplementation effectively improved the undesirable results mentioned above when compared to the HFru group. Meanwhile, fisetin significantly suppressed the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) pathway and activated the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in mice fed with HFru. Our findings demonstrated that fisetin exerted the beneficial effects in HFru-feeding mice, which might be associated with suppression of NF-κB and activation of the Nrf2 pathway.

Protective effects on mitochondria and anti-aging activity of polysaccharides from cultivated fruiting bodies of Cordyceps militaris.

Cordyceps militaris (L.) Link is an entomopathogenic fungus parasitic to Lepidoptera larvae, and is widely used as a folk tonic or invigorant for longevity in China. Although C. militaris has been used in traditional Chinese medicine for millennia, there is still a lack convincing evidence for its anti-aging activities. This study was performed to investigate the effects of polysaccharides from cultivated fruiting bodies of C. militaris (CMP) on mitochondrial injury, antioxidation and anti-aging activity. Fruiting bodies of C. militaris were cultivated artificially under optimized conditions. The spectrophotometric method was used to measure thiobarbituric acid reactive substances (TBARS), mitochondrial swelling, and activities of scavenging superoxide anions in vitro. D-galactose (100 mg/kg/day) was injected subcutaneously into back of the neck of mice for 7 weeks to induce an aging model. The effects of CMP on the activities of catalase (CAT), surperoxide dismutase (SOD), glutathione peroxidase (GPx) and anti-hydroxyl radicals were assayed in vivo using commercial monitoring kits. The results showed that CMP could inhibit mitochondrial injury and swelling induced by Fe²(+)-L-Cysteine in a concentration- dependent manner and it also had a significant superoxide anion scavenging effect. Moreover, the activities of CAT, SOD, GPx and anti-hydroxyl radicals in mice liver were increased significantly by CMP. These results indicate that CMP protects mitochondria by scavenging reactive oxygen species (ROS), inhibiting mitochondrial swelling, and increasing the activities of antioxidases. Therefore, CMP may have pharmaceutical values for mitochondrial protection and anti-aging. CMP was the major bioactive component in C. militaris.