pseudoginsenoside-f11 and Alzheimer-Disease

Deglycosylation is the most important gastrointestinal metabolism in which ginsenosides are split off from glycosyl moieties by the enzymes secreted from intestinal microflora, and two possible metabolic pathways of protopanaxdiol-type ginsenosides (PPD-type ginsenosides) and protopanaxtriol-type ginsenosides (PPT-type ginsenosides) have been concluded. The former is deglycosylated at C-3 and/or C-20, and transformed to protopanaxdiol (PPD). By comparison, the latter is deglycosylated at C-6 and/or C-20, and eventually transformed to protopanaxtriol (PPT) instead. The pharmacokinetic behavior of PPD-type ginsenosides and PPT-type ginsenosides is different, mainly in a faster absorption and elimination rate of PPT-type ginsenosides, but almost all of ginsenosides have a low oral bioavailability, which is relevant to the properties, the stability in the gastrointestinal tract, membrane permeability and the intestinal and hepatic first-pass effect of ginsenosides. Fortunately, its bioavailability can be improved by means of pharmaceutical strategies, including nanoparticles, liposomes, emulsions, micelles, etc. These drug delivery systems can significantly increase the bioavailability of ginsenosides, as well as controlling or targeting drug release. Ginsenosides are widely used in the treatment of various diseases, the most famous one is the Shen Yi capsule, which is the world's first clinical application of tumor neovascularization inhibitors. Hence, this article aims to draw people's attention on ocotillol-type ginsenosides, which have prominent anti-Alzheimer's disease activity, but have been overlooked previously, such as its representative compound-Pseudoginsenoside F

Topics: Alzheimer Disease; Animals; Biological Availability; Dammaranes; Drug Delivery Systems; Emulsions; Ginsenosides; Humans; Liposomes; Micelles; Molecular Structure; Nanoparticles; Triterpenes

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

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