pseudoginsenoside-f11 and Disease-Models--Animal

Topics: Alzheimer Disease; Animals; Calpain; Chromosome Pairing; Cognitive Dysfunction; Disease Models, Animal; Ginsenosides; Glycogen Synthase Kinase 3 beta; Hippocampus; Insulin Receptor Substrate Proteins; Male; Maze Learning; Morris Water Maze Test; Proto-Oncogene Proteins c-akt; Rats; Rats, Wistar; Streptozocin; tau Proteins

Alzheimer's disease (AD) is a common neurodegenerative disease which is characterized by aggregation of amyloid beta (Aβ) and hyperphosphorylated tau. We previously reported that pseudoginsenoside-F11 (PF11), an ocotillol-type saponin, improved cognitive function and reduced Aβ aggregation in APP/PS1 mice, a familial AD model. Here, we chose senescence-accelerated mouse prone 8 (SAMP8) mice, a widely used model of aging, to investigate the effect of PF11 on sporadic AD. PF11 was orally administered to male 6-month-old SAMP8 mice for 3 months. Consistent with previous studies, SAMP8 mice showed several AD-type pathologies including cognitive impairment, Aβ deposition and tau hyperphosphorylation. We found increased protein levels of cytoplasmic amyloid precursor protein (APP) and β-site APP cleavage enzyme 1 (BACE1) in the hippocampus and cortex of SAMP8 mice. The protein level of demethylated protein phosphatase 2A (PP2A) was elevated in SAMP8 animals and the protein level of leucine carboxyl methyltransferase 1 (LCMT-1) was reduced. PF11 attenuated learning and memory impairments in the novel object recognition test and Morris water maze. PF11 promoted the transport of APP from cytoplasm to plasma membrane and decreased the abnormally high expression of BACE1 in hippocampus and cortex of SAMP8 mice. The elevated protein level of demethylated PP2A and the reduced expression of LCMT-1 in hippocampus and cortex of SAMP8 were also attenuated by PF11. Together, our findings indicate that PF11 has beneficial effects on AD-like pathological changes in SAMP8 mice and may act by inhibiting amyloidogenic processing of APP and attenuating tau hyperphosphorylation.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Amyloid beta-Protein Precursor; Amyloid Precursor Protein Secretases; Animals; Aspartic Acid Endopeptidases; Cerebral Cortex; Cognitive Dysfunction; Disease Models, Animal; Ginsenosides; Hippocampus; Locomotion; Male; Maze Learning; Mice; Protein O-Methyltransferase; Protein Phosphatase 2; tau Proteins

Calcium overload has been reported to trigger neuronal death following stroke. Pseudoginsenoside-F11 (PF11), an ocotillol-type ginsenoside with various neuroprotective activities, has displayed therapeutic efficacy against permanent ischemic stroke. The present study examined the protective potential of PF11 in rats subjected to 2-h transient middle cerebral artery occlusion (tMCAO) and in cultured primary cortical neuron (PCN) exposed to oxygen-glucose deprivation/reoxygenation (OGD/R). Single intravenous administration of PF11 (12 mg/kg) significantly reduced infarct volume, brain edema, neurological deficit and cortex neuron loss at 24 h after reperfusion. Immunoblotting and immunofluorescence demonstrated that PF11 inhibited the over activation of μ-Calpain and the reduction of calcium calmodulin kinase II-α, reduced the degradation of sarcoplasmic/endoplasmic reticulum ATPase-2 and alleviated endoplasmic reticulum stress (ERS) in tMCAO rats. What's more, rats treated with PF11 (12 mg/kg) intravenously immediately after reperfusion, and then intraperitoneally every 24 h for 14 days exhibited lessened cortex neuron loss, reduced mortality and improved performances of rotarod, grip strength and gait patterns at 1, 4, 7, and 14 days after tMCAO. Furthermore, in vitro investigations showed PF11 increased cell viability, reduced neurites decline, restored ATP level and decreased calcium content in cultured PCN under OGD/R. Moreover, PF11 alleviated ERS, reversed the diminished levels of NMDA-2B subunit, postsynaptic density protein 95 and neuronal nitric oxide synthase both in vivo and in vitro. Our study indicates that PF11 produced neuroprotection and improved long-term outcomes while repressing calcium overload in model of transient focal ischemia, suggesting that PF11 might be a considerable candidate for stroke treatment.

Topics: Animals; Brain; Brain Edema; Calcium; Cell Death; Disease Models, Animal; Ginsenosides; Ischemic Attack, Transient; Neurons; Neuroprotective Agents; Rats

Pseudoginsenoside-F11 (PF11), an ocotillol-type ginsenoside, has been reported to exert wide-ranging neuroprotective properties. The aim of this study was to investigate the effect and potential mechanisms of PF11 on the autophagic/lysosomal pathway following ischemic stroke.. Male Sprague-Dawley rats underwent permanent middle cerebral artery occlusion (pMCAO). Cerebral ischemia outcome, TUNEL staining, Fluoro-Jade B staining were carried out 24 hours poststroke. The autophagic/lysosomal-related proteins were measured.. A single administration of PF11 significantly decreased the infarct area, reduced the brain water content, and improved neurological functions, even 4 hours after the onset of pMCAO. Meanwhile, PF11 lessened the ischemic insult-mediated loss of neurons and activation of astrocytes and microglia. Furthermore, PF11 attenuated pMCAO-induced accumulations of autophagosomes and apoptosis. We further observed a remarkable effect of PF11 in reversing the ischemic insult-induced accumulation of autophagosomes (LC3-II) and abnormal aggregation of autophagic proteins (SQSTM1 and ubiquitin). Furthermore, PF11 was capable of improving lysosomal function and lysosome/autophagosome fusion following pMCAO, and this change was reversed by the lysosomal inhibitor chloroquine. Also, the improvement of ischemic outcome and the antiapoptotic effect induced by PF11 was reversed by CQ.. These findings indicate that the autophagic flux is impaired in a rat model of pMCAO, and that PF11 exerts an excellent protective effect against ischemic stroke by alleviating autophagic/lysosomal defects.

Topics: Animals; Apoptosis; Autophagy; Brain; Brain Edema; Brain Ischemia; Chloroquine; Disease Models, Animal; Ginsenosides; Lysosomes; Male; Neuroglia; Neurons; Neuroprotective Agents; Rats, Sprague-Dawley; Stroke

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by amyloid β (Aβ) deposits, elevated oxidative stress, and apoptosis of the neurons. Pseudoginsenoside-F11 (PF11), a component of Panax quinquefolium (American ginseng), has been demonstrated to antagonize the learning and memory deficits induced by scopolamine, morphine and methamphetamine in mice. In the present study, we investigated the effect of PF11 on AD-like cognitive impairment both in mice induced by intracerebroventricular injection of Aβ1-42 (410 pmol) and in Tg-APPswe/PS1dE9 (APP/PS1) mice. It was found that oral treatment with PF11 significantly mitigated learning and memory impairment in mice given Aβ1-42-treated mice for 15 days at doses of 1.6 and 8 mg/kg and APP/PS1 for 4 weeks at a dose of 8 mg/kg as measured by the Morris water maze and step-through tests. In APP/PS1 mice, PF11 8 mg/kg significantly inhibited the expressions of β-amyloid precursor protein (APP) and Aβ1-40 in the cortex and hippocampus, restored the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and decreased the production of malondialdehyde (MDA) in the cortex. It also noticeably improved the histopathological changes in the cortex and hippocampus and downregulated the expressions of JNK 2, p53 and cleaved caspase 3 in the hippocampus. These findings suggested that the inhibitory effect on amyloidogenesis and oxidative stress and some beneficial effects on neuronal functions might contribute to the recognition improvement effect of PF11 in APP/PS1 mice. Cumulatively, the present study indicated that PF11 may serve as a potential therapeutic agent for the treatment of AD.

Topics: Alzheimer Disease; Amnesia; Animals; Brain; Caspase 3; Disease Models, Animal; Female; Ginsenosides; Glutathione Peroxidase; Male; Malondialdehyde; Maze Learning; Mice; Mitogen-Activated Protein Kinase 9; Superoxide Dismutase; Tumor Suppressor Protein p53