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Neuroinflammation is an inflammatory response in the nervous system that is associated with various neurological diseases including Alzheimer's diseases and others. Many studies evaluated the anti-inflammatory potential of Santalum album (S. album) extract, but none of them analyzed its effects against neuroinflammatory response in vitro. In addition, the precise mechanism underlying the anti-inflammatory effect of the extract has not yet been elucidated. Therefore, in this study, we investigated the effect of S. album extract on modulation of toll-like receptor 3 (TLR3) agonist polyinosnic-polycytidylic acid (PolyI:C)-induced neuroinflammatory response in human neuroblastoma cells. The TLR3-mediated immune response was differentially modulated by S. album extract in SH-SY5Y cells. In addition, treatment of cells with the conditioned medium (CM) of S. album extract significantly increased the mRNA levels of IFN-β, IFN-α, MxA and OAS-1 and decreased IL-6, CXCL8, CCL2 and IP-10. S. album extract has indirectly affected the expression of IFNs and inflammatory cytokines in SH-SY5Y cells. Furthermore, the extract was able to modulate PolyI:C-induced inflammatory response in Caco2 cells. Overall, S. album was capable to attenuate PolyI:C-induced neuroinflammatory effect through the induction of TLR2, TLR4 and the modulation of TLR negative regulators of the TRAF3, IRF3 and NF-κB pathways., (© 2020 John Wiley & Sons Ltd.)

Forest bathing is suggested to have beneficial effects on various aspects of human health. Terpenes, isoprene based-phytochemicals emitted from trees, are largely responsible for these beneficial effects of forest bathing. Although the therapeutic effects of terpenes on various diseases have been revealed, their effects on neuronal health have not yet been studied in detail. Here, we screened 16 terpenes that are the main components of Korean forests using Drosophila Alzheimer's disease (AD) models to identify which terpenes have neuroprotective effects. Six out of the 16 terpenes, ρ-cymene, limonene (+), limonene (-), linalool, α-pinene (+), and β-pinene (-), partially suppressed the beta amyloid 42 (Aβ42)-induced rough eye phenotype when fed to Aβ42-expressing flies. Among them, limonene (+) restored the decreased survival of flies expressing Aβ42 in neurons during development. Limonene (+) treatment did not affect Aβ42 accumulation and aggregation, but did cause to decrease cell death, reactive oxygen species levels, extracellular signal-regulated kinase phosphorylation, and inflammation in the brains or the eye imaginal discs of Aβ42-expressing flies. This neuroprotective effect of limonene (+) was not associated with autophagic activity. Our results suggest that limonene (+) has a neuroprotective function against the neurotoxicity of Aβ42 and, thus, is a possible therapeutic reagent for AD.

The Nardostachys jatamansi DC (NJ) root has been used as a sedative or analgesic to treat neurological symptoms and pain in traditional Korean medicine. Here, we investigate the potential effects of NJ on Alzheimer's disease (AD) and reveal the molecular mechanism through which NJ exerts its effects. The neuroprotective effect of the NJ root ethanol extract against β amyloid (Aβ) toxicity was examined in vitro using a cell culture system and in vivo using a Drosophila AD model. The NJ extract and chlorogenic acid, a major component of NJ, inhibited Aβ-induced cell death in SH-SY5Y cells. Moreover, the NJ extract rescued the neurological phenotypes of the Aβ42-expressing flies (decreased survival and pupariation rate and a locomotor defect) and suppressed Aβ42-induced cell death in the brain. We also found that NJ extract intake reduced glial cell number, reactive oxygen species level, extracellular-signal-regulated kinase (ERK) phosphorylation, and nitric oxide level in Aβ42-expressing flies, without affecting Aβ accumulation. These data suggest that the neuroprotective activity of NJ might be associated with its antioxidant and anti-inflammatory properties, as well as its inhibitory action against ERK signaling; thus, NJ is a promising medicinal plant for the development of AD treatment.

Alzheimer's disease (AD), the most common neurodegenerative disease, has a complex and widespread pathology that is characterized by the accumulation of amyloid [Formula: see text]-peptide (A[Formula: see text]) in the brain and various cellular abnormalities, including increased oxidative damage, an amplified inflammatory response, and altered mitogen-activated protein kinase signaling. Based on the complex etiology of AD, traditional medicinal plants with multiple effective components are alternative treatments for patients with AD. In the present study, we investigated the neuroprotective effects of an ethanol extract of Coriandrum sativum (C. sativum) leaves on A[Formula: see text] cytotoxicity and examined the molecular mechanisms underlying the beneficial effects. Although recent studies have shown the benefits of the inhalation of C. sativum oil in an animal model of AD, the detailed molecular mechanisms by which C. sativum exerts its neuroprotective effects are unclear. Here, we found that treatment with C. sativum extract increased the survival of both A[Formula: see text]-treated mammalian cells and [Formula: see text]42-expressing flies. Moreover, C. sativum extract intake suppressed [Formula: see text]-induced cell death in the larval imaginal disc and brain without affecting A[Formula: see text]42 expression and accumulation. Interestingly, the increases in reactive oxygen species levels and glial cell number in AD model flies were reduced by C. sativum extract intake. Additionally, C. sativum extract inhibited the epidermal growth factor receptor- and A[Formula: see text]-induced phosphorylation of extracellular signal-regulated kinase (ERK). The constitutively active form of ERK abolished the protective function of C. sativum extract against the [Formula: see text]-induced eye defect phenotype in Drosophila. Taken together, these results suggest that C. sativum leaves have antioxidant, anti-inflammatory, and ERK signaling inhibitory properties that are beneficial for patients with AD.

Alzheimer's disease (AD) is the most common neurodegenerative disorder, characterized by progressive neuronal loss with amyloid β-peptide (Aβ) plaques. Despite several drugs currently used to treat AD, their beneficial effects on AD progress remains under debate. Here, we established a rapid in vivo screening system using Drosophila AD models to assess the neuroprotective activities of medicinal plants that have been used in traditional Chinese medicine. Among 23 medicinal plants tested, the extracts from five plants, Coriandrum sativum, Nardostachys jatamansi, Polygonum multiflorum (P. multiflorum), Rehmannia glutinosa, and Sorbus commixta (S. commixta), showed protective effects against the Aβ42 neurotoxicity. We further characterized the neuroprotective activity of ethanol extracts from P. multiflorum and S. commixta. Aβ42-expressing flies that we used showed AD neurological phenotypes, such as decreased survival and motility and increased cell death and reactive oxygen species level. However, feeding these flies extracts from P. multiflorum or S. commixta showed strong suppression of such phenotypes. Similar results were observed in human cells, so that the treatment of P. multiflorum and S. commixta extracts increased the viability of Aβ-treated SH-SY5Y cells. Moreover, 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside, one of the main constituents of P. multiflorum, also showed similar protective activity against Aβ42 cytotoxicity in both Drosophila and human cells. Taken together, our results suggest that both P. multiflorum and S. commixta have therapeutic potential for the treatment of neurodegenerative diseases, such as AD.

Background: Literature data indicate that brain-derived neurotrophic factor (BDNF), cyclic-AMP response element-binding protein (CREB) and phospho-CREB (pCREB) may have a place in depression. BDNF belongs to the neurotrophin family that plays an important role in proliferation, survival and differentiation of different cell populations in the mammalian nervous system. The herbal mixture used in the present study consists of Euphoria longana, Houttuynia cordata and Dioscorea japonica. The purpose of the present study was to determine the neuroprotective effect of herbal mixture. We also tested the hypothesis that administration of herbs reverses memory deficits and promotes the protein expression of BDNF in the mouse brain., Methods: Mice were randomized into four different treatment groups (n = 10/group). Normal and stress groups received regular lab chow without stress and under stress conditions, respectively, for 3 weeks. The animals in the stress group were immobilized for 4 hours a day for 2 weeks. Different doses of herbal mixture (206 and 618 mg/kg) were administered for 3 weeks to those mice under stress conditions. Mice were analyzed by behavioral tests and immunoblotting examination in the hippocampus and cortex. An additional in vitro investigation was performed to examine whether herbs induce neurotoxicity in a human neuroblastoma cell line, SH-SY5Y cells., Results: No significant toxicity of herbs on human neuroblastoma cells was observed. These herbs demonstrated an inductive effect on the expression of BDNF, pCREB and pAkt. For spatial working memory test, herbal mixture fed mice exhibited an increased level of spontaneous alternation (p < 0.01) compared to those in stress conditions. Moreover, herbal mixture produced highly significant (p < 0.01) reduction in the immobility time in the tail suspension test. Mice in the herbal mixture groups demonstrated lower serum corticosterone concentration than mice in the stress group (p < 0.05). Effects of the oral administration of herbal mixture on protein levels of BDNF in the hippocampi and cortices were significant., Conclusions: Our study showed that herbal mixture administration has antidepressant effects in mice. It is proposed that adverse events such as stress and depression can modulate the expression of molecular players of cellular plasticity in the brain.

SuHeXiang Wan (SHXW), a Chinese traditional medicine, has been used to treat infantile convulsions, seizures and strokes. Previously, we reported that modified SHXW, called KSOP1009, suppressed the hyper-activation of c-Jun N-terminal kinase (JNK) and Alzheimer's disease (AD)-like phenotypes in amyloid-β42 (Aβ42)-expressing Drosophila AD models. In the present study, we, further, investigated the detailed mechanism by which KSOP1009 suppresses the AD-like phenotypes of the model flies. As seen in the brains of AD patients, pan-neuronal expression of Aβ42 in Drosophila increased activation of extracellular signal-regulated kinase (ERK), which was monitored by its phosphorylation level, and the number of glial cells in the brain. Suppression of caspase activity did not affect these phenomena, suggesting that Aβ42 induces ERK activation and glial cell proliferation independently of apoptotic processes. KSOP1009 intake significantly reduced the level of ERK activation and the number of glial cells. Moreover, KSOP1009 intake also effectively decreased the defects in the wing vein formation induced by Epidermal growth factor receptor (Egfr) overexpression in fly wings, suggesting that it may contain an inhibitory substance that inhibits the EGFR/ERK signaling pathway. In addition, the Aβ42-induced locomotive defect was partially rescued by inhibition of the elevated ERK activity through its antagonistic drug treatment. Taken together, these results suggest that KSOP1009 exerts its therapeutic effect by inhibiting the EGFR/ERK pathway and glial cell proliferation and by suppressing the JNK pathway and apoptosis.

Context: The β-amyloid (Aβ) peptide aggregation with accompanying oxidative stress plays the major role in the pathogenesis of Alzheimer's disease (AD). Some natural compounds, including borneol, shed promising light on AD treatment., Objective: The present study was designed to investigate the antioxidative, antiapoptotic effects, and neuroprotection of borneol in human neuroblastoma cells (SH-SY5Y)., Materials and Methods: Oxidative stress was induced by administering 50 µM Aβ into SH-SY5Y cells. Neuroprotective effect of commercially available borneol was examined by determining cell viability with the MTT assay. Intracellular reactive oxygen species (ROS) generation was measured using a fluorometer with further examination of heme oxygenase-1 (HO-1) and nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) expression. Apoptosis was examined by measuring the ratio of B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (Bax)., Results: Our data indicated that Aβ-induced cell cytotoxicity was inhibited by 100 µM of (-) and (+) borneol treatment. Treatment of borneol significantly decreased ROS generation (P < 0.01). The expression of HO-1 and nuclear translocation of Nrf2 were increased by Aβ treatment. This nuclear translocation of Nrf2 was further increased by administration of borneol. Compared with the Aβ treated group, the (+) borneol treated group significantly increased Bcl-2 expression with decreased expression of Bax., Discussion and Conclusion: Borneol protected SH-SY5Y cells against Aβ-induced toxicity, exerted an antioxidative effect and suppressed apoptosis. It increases our knowledge about neuroprotective mechanism of borneol, and it is hopeful to be a candidate compound for developing therapeutic drug for the prevention and treatment of AD and other Aβ-related neurodegenerative diseases.

Aim of the Study: SuHeXiang Wan (SHXW) is a Chinese traditional medicinal prescription that consists of 15 crude herbs. SHXW has been used to treat central nervous depression, seizures, infantile convulsion and stroke, and its essential oil has been shown to have anticonvulsant and antioxidative activity. The goal of this study was to investigate the beneficial effects of SHXW on the neurological phenotypes of Drosophila AD models., Materials and Methods: We evaluated the effects of a modified SHXW (called KSOP1009) intake on the AD-like phenotypes of Drosophila AD models, which express human Aβ42 in their developing eyes or neurons., Results: When the flies were kept on the media containing 5 μg/ml of KSOP1009 extract, Aβ42-induced eye degeneration, apoptosis, and the locomotive dysfunctions were strongly suppressed. However, Aβ42 fibril deposits in the Aβ42 overexpressing model were not affected by treatment with KSOP1009 extract. Conversely, KSOP1009 extract intake significantly suppressed the constitutive active form of hemipterous, a JNK activator, while it induced eye degeneration and JNK activation, which has been recognized as an important mediator of Aβ42-associated neuro-cytotoxicity., Conclusions: In conclusion, the results of this study suggest that KSOP1009 confers a therapeutic potential to AD-like pathology of Aβ42 overexpressing Drosophila model via suppression of the hyperactivation of JNK activity and apoptosis., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Chukmesundan (CMSD), composed of the following 8 medicinal herbs including Panex ginseng C.A. MEYER, Atractylodes macrocephala KOID, Poria cocos WOLF, Pinellia ternata BREIT, Brassica alba BOISS, Aconitum carmichaeli DEBX, Cynanchum atratum BGE and Cuscuta chinensis LAM. CMSD is being used in Korea for the treatment of various symptoms accompanying hypertension and cerebrovascular disorders. This study was carried out to examine the effects of CMSD on cultured primary neuron cell, cell cytotoxicity and lipid peroxidation in Abeta-treated cells. Cell death was enhanced by addition of Abeta. Pretreatment of CMSD attenuated in cell killing induced by Abeta. The protective effect of the CMSD water extracts on Abeta-induced neuronal death was also observed by lactate dehydrogenase assay using cultured astrocyte cells. Abeta-induced cell death was protected by the water extract of CMSD in a dose-dependent manner, and 25-50 microg/ml was the most effective concentration. CMSD has been also shown to protect primary cultured neurons from N-methyl-D: -aspartate receptor-mediated glutamate toxicity. It was in vivo evidenced that CMSD protects neurons against ischemia-induced cell death. Moreover, oral administration of CMSD into mice prevented ischemia-induced learning disability and rescued hippocampal CA1 neurons from lethal ischemic damage. The neuroprotective action of exogenous CMSD was also confirmed by counting synapses in the hippocampal CA1 region. The presence of CMSD in neuron cultures rescued the neurons from nitrogen oxide (NO)-induced death. From these, it was suggested that CMSD may exert its neuroprotective effect by reducing the NO-mediated formation of free radicals or antagonizing their toxicity.

Chukmesundan (CMSD) is composed of 8 medicinal herbs including Panex ginseng C.A. MEYER, Atractylodes macrocephala KOID, Poria cocos WOLF, Pinellia ternata BREIT, Brassica alba BOISS, Aconitum carmichaeli DEBX, Cynanchum atratum BGE, and Cuscuta chinensis LAM and used for the treatment of various symptoms accompanying hypertension and cerebrovascular disorders. This study was carried out to examine the effects of CMSD on N-methyl-D-aspartate (NMDA)-evoked, and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-evoked nitric oxide synthase (NOS) activity in mouse brain. In adult forebrain, CMSD influences neuronal maintenance and is neuroprotective in several injury models through mechanisms that are incompletely understood. Interaction is observed between CMSD and nitric oxide (NO). Because NO affects both neural plasticity and degeneration, we hypothesized that CMSD might rapidly modulate NO production. Using in vivo microdialysis we measured conversion of L-[14C] arginine to L-[14C] citrulline as an accurate reflection of NOS activity in adult mouse hippocampus. CMSD significantly reduced NOS activities to 62% of basal levels within 2 days of onset of delivery and maintained NOS activity at less than 45% of baseline throughout 3 days of delivery. These effects did not occur with control (distilled water) and were not mediated by effect of CMSD on glutamate levels. In addition, simultaneous delivery of CMSD treatment prevented significant increases in NOS activity triggered by the glutamate receptor agonists NMDA and AMPA. Rapid suppression by CMSD of basal and glutamate-stimulated NOS activity may regulate neuromodulatory functions of NO or protect neurons from NO toxicity and suggests a novel mechanism for rapidly mediating functions of CMSD. It is shown that NMDA receptor stimulation leads to activation of p21ras (Ras) through generation of NO via neuronal NOS. The competitive NOS inhibitor, L-nitroarginine methyl ester, and CMSD prevents Ras activation elicited by NMDA, thus supporting the physiologic relevance of endogenous NO regulation of Ras. These results suggest that Ras is a physiologic target of endogenously produced NO and indicates a signaling pathway for NMDA receptor activation that may be important for long-lasting neuronal responses.

Bombycis corpus (BC) or Bombyx Batryticatus, a batryticated silkworm and white-stiff silkworm, is a drug consisting of the dried larva of silkworm, Mobyz mori L., dead and stiffened due to the infection of Beauveria (Bals.) Vuill. In a previous paper (Kim et al., Pharmacol. Res., 43, 12-16, 2001), BC was shown to protect amyloid-beta-induced cytotoxicity. In the present study, we have found that BCE can prevent or reduce the neurotoxic actions in the hippocampus of the glutamate agonists N-methyl-D-aspartic acid (NMDA) in vitro or alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainic acid in vitro. Pre-treatment with BCE (0, 1, 2, 5, and 10 microg/ml for 6-8 h) protected primary hippocampal cultures from embryonic day 18 (E18) embryos against NMDA-induced toxicity (0.1, 1, 10, and 50 nM/ml). BCE added either with NMDA (1 mM) or 1 h later had lesser, but still significant, protective actions. BCE also reduced NMDA-induced toxicity (1 mM). BCE (10 microg/ml) protected cultured neurons against the neurotoxic actions of either AMPA (25 microM) or kainic acid (1 mM) as well. Because the release of glutamate has been implicated in the neural damage after cerebral ischemia and other neural insults, these results suggest that BCE may contribute significantly to protect human brain to such damage.