Ligularia fischeri inhibits endothelial cell proliferation, invasion and tube formation through the inactivation of mitogenic signaling pathways and regulation of vascular endothelial cadherin distribution and matrix metalloproteinase expression.

Ligularia fischeri (LF) has been used as an edible herb and traditional medicine for the treatment of inflammatory and infectious diseases. In the present study, we report the effects and molecular mechanism of the ethanolic extract of LF on cell proliferation, invasion and tube formation in human umbilical vein endothelial cells (HUVECs). LF-mediated inhibition of cell proliferation was accompanied by reduced expression of cell cycle-related proteins such as cyclin-dependent kinases (Cdks) and cyclins, leading to pRb hypophosphorylation and G1 phase cell cycle arrest. We also show that LF treatment inhibited cell invasion and tube formation in HUVECs. These anti-angiogenic activities of LF were associated with the inactivation of mitogenic signaling pathways, induction of vascular endothelial (VE)-cadherin distribution at cell-cell contacts and inhibition of matrix metalloproteinase (MMP) expression. Collectively, our findings demonstrate the pharmacological functions and molecular mechanisms of LF in regulating endothelial cell fates, and support further development as a potential therapeutic agent for the treatment and prevention of angiogenesis-related disorders including cancer.

Anti-angiogenic effects of Siegesbeckia glabrescens are mediated by suppression of the Akt and p70S6K-dependent signaling pathways.

Siegesbeckia glabrescens (SG) Makino (Compositae) has been used as a traditional medicine for the treatment of allergic and inflammatory diseases. In the present study, we report the effects and molecular mechanism of an ethanolic extract of SG on cell proliferation, migration and tube formation in vascular endothelial growth factor-A (VEGF-A)-treated human umbilical vein endothelial cells. SG treatment inhibited VEGF-A-stimulated endothelial cell proliferation through downregulation of cyclin D and upregulation of cyclin-dependent kinase inhibitors such as p27Kip1 and p21WAF1/Cip1. In addition, SG inhibited VEGF­A-stimulated endothelial cell migration and tube formation. These anti-angiogenic activities of SG were mediated by inactivation of the Akt- and p70S6K-dependent signaling pathways. Collectively, our findings demonstrate the pharmacological roles and molecular mechanism of SG in regulating angiogenic responses and support further evaluation and development of SG as a potential therapeutic agent for the treatment and prevention of angiogenesis-related diseases including cancer.

An investigation into the ameliorating effect of black soybean extract on learning and memory impairment with assessment of neuroprotective effects.

BACKGROUND: The physiological effects of the non-anthocyanin fraction (NAF) in a black soybean seed coat extract on Aß-induced oxidative stress were investigated to confirm neuroprotection. In addition, we examined the preventive effect of NAF on cognitive defects induced by the intracerebroventricular (ICV) injection of Aß. METHODS: Levels of cellular oxidative stress were measured using 2',7'-dichlorofluorescein diacetate (DCF-DA). Neuronal cell viability was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assay. To investigate in vivo anti-amnesic effects of NAF by using Y-maze and passive avoidance tests, the learning and memory impairment in mice was induced by Aß. After in vivo assays, acetylcholinesterase (AChE) activity and level of malondialdehyde (MDA) in the mouse brain were determined to confirm the cognitive effect. Individual phenolics of NAF were qualitatively analyzed by using an ultra-performance liquid chromatography (UPLC) Accurate-Mass Quadrupole Time of-Flight (Q-TOF) UPLC/MS. RESULTS: A NAF showed cell protective effects against oxidative stress-induced cytotoxicity. Intracellular ROS accumulated through Aß1-40 treatment was significantly reduced in comparison to cells only treated with Aß1-40. In MTT and LDH assay, the NAF also presented neuroprotective effects on Aß1-40-treated cytotoxicity. Finally, the administration of this NAF in mice significantly reversed the Aß1-40-induced cognitive defects in in vivo behavioral tests. After behavioral tests, the mice brains were collected in order to examine lipid peroxidation and AChE activity. AChE, preparation was inhibited by NAF in a dose-dependent manner. MDA generation in the brain homogenate of mice treated with the NAF was decreased. Q-TOF UPLC/MS analyses revealed three major phenolics from the non-anthocyanin fraction; epicatechin, procyanidin B1, and procyanidin B2. CONCLUSIONS: The results suggest that the NAF in black soybean seed coat extracts may improve the cytotoxicity of Aß in PC12 cells, possibly by reducing oxidative stress, and also have an anti-amnesic effect on the in vivo learning and memory deficits caused by Aß. Q-TOF UPLC/MS analyses showed three major phenolics; (-)-epicatechin, procyanidin B1, and procyanidin B2. Above results suggest that (-)-epicatechins are the major components, and contributors to the anti-amnesic effect of the NAF from black soybean seed coat.

Black soybean extract protects against TMT-induced cognitive defects in mice.

To find a neuroactive compound with a potent inhibitory effect on acetylcholinesterase (AChE) and in vivo anti-amnesic activity from natural resources, we evaluated anthocyanins and nonanthocyanins from black soybean extract. Nonanthocyanins from black soybean extract were the most potent and dose-dependent AChE inhibitors. Intracellular reactive oxygen species accumulation resulting from H2O2 treatment was significantly decreased compared with cells treated with H2O2 only. Nonanthocyanins were also neuroprotective against H2O2 treated neurotoxicity by 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assay. Finally, nonanthocyanins from black soybean in the preadministration group attenuated trimethyltin (TMT)-induced memory injury in both in vivo tests. AChE, prepared from mice brain tissues, was inhibited by nonanthocyanins from black soybean in a dose-dependent manner. Malondialdehyde generation in the brain homogenates of mice treated with nonanthocyanins from black soybean was decreased. We concluded that nonanthocyanins from black soybean had an efficacious in vitro AChE inhibitory activity, and protected against H2O2-induced neurotoxicity. In addition, our findings suggest that nonanthocyanins from black soybean may improve the TMT-induced learning and memory deficit because of AChE inhibition of mice brain tissue. Consequently, these results demonstrate that the nonanthocyanins from black soybean could possess a wide range of beneficial activities for neurodegenerative disorders.

Blueberry (Vaccinium virgatum) leaf extracts protect against Aß-induced cytotoxicity and cognitive impairment.

The ethylacetate (EtOAc) fraction of blueberry leaf extract was investigated to examine the in vivo antiamnesic effects against amyloid ß protein (Aß)-induced learning and memory deficit. The fraction showed the highest antioxidant activities, and the generation of intracellular reactive oxygen species was significantly decreased. Cell viability assays revealed the in vitro cytoprotective effects of the fraction, and the cytoplasmic lactate dehydrogenase release into the medium was dose-dependently inhibited. In addition, a chlorogenic acid was identified as a predominant phenolic compound by high-performance liquid chromatography analysis. Antiamnesic effects were evaluated by using in vivo the Y-maze and passive avoidance tests, and preadministration of the fraction attenuated Aß-induced memory impairment in both in vivo experiments. Acetylcholinesterase prepared from mice brain was inhibited by the fraction, and malondialdehyde generation in the brain homogenate was also decreased. These findings suggest that the EtOAc fraction of blueberry leaf extract could possess a wide range of physiological effects against neurodegenerative diseases.

Ameliorating effects of aged garlic extracts against Aß-induced neurotoxicity and cognitive impairment.

BACKGROUND: In vitro antioxidant activities and neuron-like PC12 cell protective effects of solvent fractions from aged garlic extracts were investigated to evaluate their anti-amnesic functions. Ethyl acetate fractions of aged garlic had higher total phenolics than other fractions. METHODS: Antioxidant activities of ethyl acetate fractions from aged garlic were examined using 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt (ABTS) and malondialdehyde (MDA) inhibitory effect using mouse whole brain homogenates. Levels of cellular oxidative stress as reactive oxygen species (ROS) accumulation were measured using 2',7'-dichlorofluorescein diacetate (DCF-DA). PC12 cell viability was investigated by 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and lactate dehydtrogenase (LDH) assay. The learning and memory impairment in institute of cancer research (ICR) mice was induced by neurotoxic amyloid beta protein (Aß) to investigate in vivo anti-amnesic effects of aged garlic extracts by using Y-maze and passive avoidance tests. RESULTS: We discovered that ethyl acetate fractions showed the highest ABTS radical scavenging activity and MDA inhibitory effect. Intracellular ROS accumulation resulting from Aß treatment in PC12 cells was significantly reduced when ethyl acetate fractions were presented in the medium compare to PC12 cells which was only treated with Aß only. Ethyl acetate fractions from aged garlic extracts showed protection against Aß-induced neurotoxicity. Pre-administration with aged garlic extracts attenuated Aß-induced learning and memory deficits in both in vivo tests. CONCLUSIONS: Our findings suggest that aged garlic extracts with antioxidant activities may improve cognitive impairment against Aß-induced neuronal deficit, and possess a wide range of beneficial activities for neurodegenerative disorders, notably Alzheimer's disease (AD).

Vanillin, 4-hydroxybenzyl aldehyde and 4-hydroxybenzyl alcohol prevent hippocampal CA1 cell death following global ischemia.

Mongolian gerbils subjected to transient global ischemia exhibit neuroprotection against ischemic neuronal cell death in the hippocampal CA1 region when treated with vanillin, 4-hydroxybenzyl aldehyde (4-HBAL) and 4-hydroxybenzyl alcohol (4-HBA), which are active components of Gastrodia elata Blume. Pre- and post-insult vanillin, 4-HBAL and 4-HBA treated-animals showed a significant increase in neuronal survival (66.32%, 43.21% and 64.58%, respectively) compared to vehicle-treated animals. Animals exhibited a gender difference in this neuroprotective effect. To study the neuroprotective mechanism of 4-HBA, we investigated N-methyl-d-aspartate (NMDA) receptor 1 (NR1), 8-hydroxy-2'-deoxyguanosine (8-OHdG), and gamma-aminobutyric acid transaminase (GABA-T) immunoreactivity at various times after ischemic insults. Treatment with 4-HBA did not affect NR1 expression levels, down-regulated 8-OHdG immunoreactivity, and increased GABA-T expression levels after global ischemia, suggesting that 4-HBA inhibited NR1 stimulation. Moreover, GABA-T was rapidly increased in the early stage after ischemia, which might enhance the survival of cells by supplying energy to the CA1 region. These results suggest that 4-HBA inhibits oxidative stress and excitotoxicity for at least 12 h and suppresses neuronal death in CA1 region. Diethyl ether fractions of GE scavenged hydroxyl radical (OH.) and showed antioxidant activity on lipid peroxidation. Vanillin and 4-HBA treatment blocked oxidative damage in PC12 cells. The neuroprotective effect has therapeutic significance and these compounds need to be evaluated for potential use in protecting against neuronal cell damage during stroke.

Ether fraction of methanol extracts of Gastrodia elata, medicinal herb protects against neuronal cell damage after transient global ischemia in gerbils.

Gastrodia elata (GE), a medicinal herb, has been used traditionally for the treatment of convulsive diseases such as epilepsy in oriental countries including South Korea and still occupies an important place in traditional medicine in Asia. We designed this study to examine whether the ether fraction of methanol extracts (EFME) of GE protects the hippocampal neuronal damage induced by transient global ischemia in a gerbil model. Gerbils were treated with the EFME of GE (200 or 500 mg/kg per day, p.o.) for 14 days before brain ischemia. The lower dose of EFME of GE failed to attenuate the hippocampal neuronal damage in the CA1 region. However, the higher dose of EFME of GE attenuated the hippocampal neuronal damage in the CA1 region. The present results show that the EFME of GE has a protective effect against neuronal damage following global ischemia in gerbils.

Ethyl ether fraction of Gastrodia elata Blume protects amyloid beta peptide-induced cell death.

Alzheimer's disease is the most common cause of dementia in the elderly. Recently, it has been reported that Alzheimer's disease is associated with cell death in neuronal cells including the hippocampus. Amyloid beta-peptide stimulates neuronal cell death, but the underlying signaling pathways are poorly understood. In order to develop anti-dementia agents with potential therapeutic value, we examined the effect of the herbal compound Gastrodia elata Blume (GEB) on neuronal cell death induced by amyloid beta-peptide in IMR-32 neuroblastoma cells. The fractionation of GEB was carried out in various solvents. The hydroxyl radical scavenging effect of the ethyl ether fraction was more potent than any other fractions. In cells treated with amyloid beta-peptide, the neuroprotective effect of the ethyl ether, chloroform, and butanol fractions was 92, 44, and 39%, respectively, compared with control. Taken together, these results suggest that the ethyl ether fraction of GEB contains one or more compounds that dramatically reduce amyloid beta-peptide induced neuronal cell death in vitro.