Petasites japonicus leaf extract inhibits Alzheimer's-like pathology through suppression of neuroinflammation.

Neuroinflammation is a crucial pathogenic process involved in the development and deterioration of Alzheimer's disease (AD). Petasites japonicus is known for its beneficial effects on various disease states such as allergic reaction, oxidative stress and inflammation. However, it is still unknown whether P. japonicus has protective effects on neuroinflammation, especially microgliosis related to AD. The current study aimed to investigate whether an extract of P. japonicus (named KP-1) protects from microglial cell activation in vitro and in vivo. To demonstrate the anti-neuroinflammation effects of KP-1, the current study adopted the most widely used experimental models including the lipopolysaccharide (LPS)-induced microgliosis in vitro model and amyloid beta (Aß) oligomer (AßO)-induced neuroinflammation in vivo model, respectively. As a result, KP-1 pre-treatment reduced nitric oxide (NO) production, protein levels of inducible NO synthase (iNOS) and c-Jun N-terminal kinase (JNK) phosphorylation in BV2 cells which were significantly promoted by 100 ng ml-1 LPS treatment. Similarly, KP-1 administration protected mice from AßO-induced memory impairment scored by Y-maze and novel object recognition test (NORT). Moreover, KP-1 administration suppressed AßO-induced microglial cell activation measured by counting the number of ionized calcium binding adaptor molecule 1 (Iba-1)-positive cells in both the cortex and hippocampal dentate gyrus and measuring the mRNA expression of TNFα, IL-1ß and IL-6. Furthermore, AßO-induced synaptotoxicity was prevented by KP-1 administration which is in line with behavioral changes. Collectively, these findings suggest that KP-1 could be a potential functional food for protection against neuroinflammation, and prevents or delays the progression of AD.

Trichosanthis Semen Suppresses Lipopolysaccharide-Induced Neuroinflammation by Regulating the NF-κB Signaling Pathway and HO-1 Expression in Microglia.

Neuroinflammation, which is mediated by microglia that release various inflammatory cytokines, is a typical feature of neurodegenerative diseases (NDDs), such as Alzheimer's disease and Parkinson's disease. Hence, alleviating neuroinflammation by downregulating pro-inflammatory action, and upregulating anti-inflammatory action of microglia is an efficient therapeutic target for NDDs. In this study, we evaluated whether trichosanthis semen (TS), a dried ripe seed of Trichosanthes kirilowii Maximowicz, reduces lipopolysaccharide (LPS)-induced neuroinflammation by regulating microglial responses in vitro and in vivo. Our results presented that TS reduced the release of pro-inflammatory mediators, such as nitric oxide (NO), inducible NO synthase, tumor necrosis factor-α, interleukin-1ß, and interleukin-6 via inhibition of the nuclear factor kappa B (NF-κB) signaling pathway in LPS-treated BV2 microglial cells. Moreover, TS induced anti-inflammatory mediators, such as interleukin-10, found in inflammatory zone 1, and chitinase 3-like 3 by the upregulation of heme oxygenase 1 (HO-1). We further confirmed that TS administration suppressed microglial activation, but enhanced HO-1 expression in LPS-injected mice. These results suggest that TS has anti-neuroinflammatory effects via inhibition of NF-κB signaling through the activation of HO-1, and that TS may be a therapeutical candidate for NDDs treatment.

Phytochemicals from the flowers of Prunus persica (L.) Batsch: Anti-adipogenic effect of mandelamide on 3T3-L1 preadipocytes.

Flowers of Prunus persica (L.) Batsch (Rosaceae), known as peach blossoms, have been reported to exert anti-obesity effects by improving hepatic lipid metabolism in obese mice. However, little is known regarding the anti-adipogenic effects of the phenolic compounds isolated from P. persica flowers. This study investigated the inhibitory effects of compounds extracted from P. persica flowers (PPF) on adipogenesis in 3T3-L1 murine preadipocytes using adipogenic differentiation assays. Additionally, we compared the anti-adipogenic effects of the phenolic compounds isolated from PPF, such as prunasin amide (1), amygdalin amide (2), prunasin acid (3), mandelamide (4), methyl caffeate (5), ferulic acid (6), chlorogenic acid (7), benzyl α-l-xylpyranosyl-(1 â†’ 6)-ß-d-glucopyranoside (8), prunin (9), naringenin (10), nicotiflorin (11), astragalin (12), afzelin (13), and uridine (14), on adipogenesis in 3T3-L1 murine preadipocytes. PPF and compounds 4-7 and 10 significantly inhibited adipogenesis. Among them, mandelamide (4) exhibited the maximum inhibitory activity with an IC50 of 36.04 ± 1.82 µM. Additionally, mandelamide downregulated the expression of key adipogenic markers, such as extracellular signal-regulated kinase, c-Jun-N-terminal kinase, P38, CCAAT/enhancer-binding protein α, CCAAT/enhancer-binding protein ß, peroxisome proliferator activated receptor γ, and glucocorticoid receptor. These results indicate that mandelamide is an active ingredient of PPF possessing anti-obesity properties.

Chemical Constituents of the Leaves of Butterbur (Petasites japonicus) and Their Anti-Inflammatory Effects.

Two new aryltetralin lactone lignans, petasitesins A and B were isolated from the hot water extract of the leaves of butterbur (Petasites japonicus) along with six known compounds. The chemical structures of lignans 1 and 2 were elucidated on the basis of 1D and 2D nuclear magnetic resonance (NMR) spectroscopic data, electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) spectra. Petasitesin A and cimicifugic acid D showed significant inhibitory effects on the production of both prostaglandin E2 (PGE2) and NO in RAW264.7 macrophages. The expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were inhibited by compound 1 in RAW264.7 cells. Furthermore, compounds 1 and 3 exhibited strong affinities with both iNOS and COX-2 enzymes in molecular docking studies.

Butterbur Leaves Attenuate Memory Impairment and Neuronal Cell Damage in Amyloid Beta-Induced Alzheimer's Disease Models.

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease, and is characterized by the accumulation of amyloid beta (Aß) as a pathological hallmark. Aß plays a central role in neuronal degeneration and synaptic dysfunction through the generation of excessive oxidative stress. In the present study, we explored whether leaves of Petasites japonicus (Siebold & Zucc.) Maxim. (PL), called butterbur and traditionally used in folk medicine, show neuroprotective action against Aß25⁻35 plaque neurotoxicity in vitro and in vivo. We found that PL protected Aß25⁻35 plaque-induced neuronal cell death and intracellular reactive oxygen species generation in HT22 cells by elevating expression levels of phosphorylated cyclic AMP response element-binding protein, heme oxygenase-1, and NAD(P)H quinine dehydrogenase 1. These neuroprotective effects of PL were also observed in Aß25⁻35 plaque-injected AD mouse models. Moreover, administration of PL diminished Aß25⁻35 plaque-induced synaptic dysfunction and memory impairment in mice. These findings lead us to suggest that PL can protect neurons against Aß25⁻35 plaque-induced neurotoxicity and thus may be a potential candidate to regulate the progression of AD.

Nanoscale RRAM-based synaptic electronics: toward a neuromorphic computing device.

Efforts to develop scalable learning algorithms for implementation of networks of spiking neurons in silicon have been hindered by the considerable footprints of learning circuits, which grow as the number of synapses increases. Recent developments in nanotechnologies provide an extremely compact device with low-power consumption.In particular, nanoscale resistive switching devices (resistive random-access memory (RRAM)) are regarded as a promising solution for implementation of biological synapses due to their nanoscale dimensions, capacity to store multiple bits and the low energy required to operate distinct states. In this paper, we report the fabrication, modeling and implementation of nanoscale RRAM with multi-level storage capability for an electronic synapse device. In addition, we first experimentally demonstrate the learning capabilities and predictable performance by a neuromorphic circuit composed of a nanoscale 1 kbit RRAM cross-point array of synapses and complementary metal-oxide-semiconductor neuron circuits. These developments open up possibilities for the development of ubiquitous ultra-dense, ultra-low-power cognitive computers.