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Effective drugs that can cure cognitive impairments remain elusive. Because synaptic dysfunction has been correlated with cognitive impairments, drug development to target synaptic dysfunction is important. Recently, natural compounds and crude drugs have emerged as potential therapeutic agents for cognitive disorders. However, their effects on synaptic function remain unclear, because of lack of evaluation system with high reproducibility. We have recently developed highly reproducible in vitro high‐content imaging analysis system for evaluation of synaptic function using drebrin as a marker for synaptic states. Therefore, we aimed to examine the direct effects of well‐known natural compounds and crude drugs on synaptic states using this system. Rat hippocampal neurons were treated using natural compounds (nobiletin, diosgenin and tenuifolin) and crude drugs (Uncaria Hook [UH], Bezoar Bovis [BB], Coptis Rhizome [CR], Phellodendron Bark [PB] and Polygala Root [PR]). Immunocytochemical analysis was performed, and dendrite lengths and drebrin cluster densities were automatically quantified. We found that diosgenin, tenuifolin, CR, PB and PR decreased drebrin cluster densities, and the effects of PB and PR were partially dependent on N‐methyl‐D‐aspartic acid‐type glutamate receptors (NMDARs). Nobiletin and UH did not show any effects, whereas low‐dose BB treatment increased drebrin cluster densities. Our results showed that diosgenin, tenuifolin, BB, CR, PB and PR appeared to directly change synaptic states. Particularly, the NMDAR dependency of PB and PR appears to affect synaptic plasticity. [ABSTRACT FROM AUTHOR]

ABSTRACT: Case: The Japanese ointment shiunko was given to 56 patients with clinical findings of cutaneous lesions and parasite evidence of pure cutaneous leishmaniasis (Andean cutaneous leishmaniasis, also known as UTA in Peru), as an alternative therapy because they were unable to be treated with the usual antimonial treatment for various reasons. Outcomes: Fifty‐three subjects were followed for 30 days. Fifty had confirmed remission of the lesions together with negative parasitology and healing, and three did not achieve treatment response. Three of the initially enrolled patients withdrew from the study. Conclusion: Shiunko ointment appeared to be effective in the treatment of leishmaniasis, indicating the need for further studies with an increased number of patients in order to obtain statistically significant results. [ABSTRACT FROM AUTHOR]

Macrophages play important roles in the innate immune system during infection and systemic inflammation. When bacterial lipopolysaccharide ( LPS) binds to Toll-like receptor 4 on macrophages, several signalling cascades co-operatively up-regulate gene expression of inflammatory molecules. The present study aimed to examine whether salt-inducible kinase [ SIK, a member of the AMP-activated protein kinase ( AMPK) family] could contribute to the regulation of immune signal not only in cultured macrophages, but also in vivo. LPS up-regulated SIK3 expression in murine RAW264.7 macrophages and exogenously over-expressed SIK3 negatively regulated the expression of inflammatory molecules [interleukin-6 ( IL-6), nitric oxide ( NO) and IL-12p40] in RAW264.7 macrophages. Conversely, these inflammatory molecule levels were up-regulated in SIK3-deficient thioglycollate-elicited peritoneal macrophages ( TEPM), despite no impairment of the classical signalling cascades. Forced expression of SIK3 in SIK3-deficient TEPM suppressed the levels of the above-mentioned inflammatory molecules. LPS injection (10 mg/kg) led to the death of all SIK3-knockout ( KO) mice within 48 hr after treatment, whereas only one mouse died in the SIK1- KO ( n = 8), SIK2- KO ( n = 9) and wild-type ( n = 8 or 9) groups. In addition, SIK3- KO bone marrow transplantation increased LPS sensitivity of the recipient wild-type mice, which was accompanied by an increased level of circulating IL-6. These results suggest that SIK3 is a unique negative regulator that suppresses inflammatory molecule gene expression in LPS-stimulated macrophages. [ABSTRACT FROM AUTHOR]

The development of complementary and/or alternative drugs for treatment of hepatitis C virus (HCV) infection is still needed. Antiviral compounds in medicinal plants are potentially good targets to study. Morinda citrifolia is a common plant distributed widely in Indo-Pacific region; its fruits and leaves are food sources and are also used as a treatment in traditional medicine. In this study, using a HCV cell culture system, it was demonstrated that a methanol extract, its n-hexane, and ethyl acetate fractions from M. citrifolia leaves possess anti-HCV activities with 50%-inhibitory concentrations (IC50) of 20.6, 6.1, and 6.6 μg/mL, respectively. Bioactivity-guided purification and structural analysis led to isolation and identification of pheophorbide a, the major catabolite of chlorophyll a, as an anti-HCV compound present in the extracts (IC50 = 0.3 μg/mL). It was also found that pyropheophorbide a possesses anti-HCV activity (IC50 = 0.2 μg/mL). The 50%-cytotoxic concentrations (CC50) of pheophorbide a and pyropheophorbide a were 10.0 and 7.2 μg/mL, respectively, their selectivity indexes being 33 and 36, respectively. On the other hand, chlorophyll a, sodium copper chlorophyllin, and pheophytin a barely, or only marginally, exhibited anti-HCV activities. Time-of-addition analysis revealed that pheophorbide a and pyropheophorbide a act at both entry and the post-entry steps. The present results suggest that pheophorbide a and its related compounds would be good candidates for seed compounds for developing antivirals against HCV. [ABSTRACT FROM AUTHOR]

ABSTRACT Development of complementary and/or alternative drugs for treatment of hepatitis C virus (HCV) infection is still much needed from clinical and economic points of view. Antiviral substances obtained from medicinal plants are potentially good targets to study. Glycyrrhiza uralensis and G. glabra have been commonly used in both traditional and modern medicine. In this study, extracts of G. uralensis roots and their components were examined for anti-HCV activity using an HCV cell culture system. It was found that a methanol extract of G. uralensis roots and its chloroform fraction possess anti-HCV activity with 50%-inhibitory concentrations (IC50) of 20.0 and 8.0 μg/mL, respectively. Through bioactivity-guided purification and structural analysis, glycycoumarin, glycyrin, glycyrol and liquiritigenin were isolated and identified as anti-HCV compounds, their IC50 being 8.8, 7.2, 4.6 and 16.4 μg/mL, respectively. However, glycyrrhizin, the major constituent of G. uralensis, and its monoammonium salt, showed only marginal anti-HCV activity. It was also found that licochalcone A and glabridin, known to be exclusive constituents of G. inflata and G. glabra, respectively, did have anti-HCV activity, their IC50 being 2.5 and 6.2 μg/mL, respectively. Another chalcone, isoliquiritigenin, also showed anti-HCV activity, with an IC50 of 3.7 μg/mL. Time-of-addition analysis revealed that all Glycyrrhiza-derived anti-HCV compounds tested in this study act at the post-entry step. In conclusion, the present results suggest that glycycoumarin, glycyrin, glycyrol and liquiritigenin isolated from G. uralensis, as well as isoliquiritigenin, licochalcone A and glabridin, would be good candidates for seed compounds to develop antivirals against HCV. [ABSTRACT FROM AUTHOR]

Leishmanicidal activity of 46 natural products including several fern and Betula constituents was examined. Several pterosin and atisene compounds from ferns had high activity. Among the triterpenoids the carboxyl group was found to be important for activity. In the diarylheptanoids, the linear-type and the diphenylether-type showed significant activity, and it was found that the carbonyl group at C-11 is necessary for the activity of biphenyl-types. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Dysfunction of mitochondrial activity is often associated with the onset and progress of neurodegenerative diseases. Membrane depolarization induced by Na+ influx increases intracellular Ca2+ levels in neurons, which upregulates mitochondrial activity. However, overlimit of Na+ influx and its prolonged retention ultimately cause excitotoxicity leading to neuronal cell death. To return the membrane potential to the normal level, Na+/K+‐ATPase exchanges intracellular Na+ with extracellular K+ by consuming a large amount of ATP. This is a reason why mitochondria are important for maintaining neurons. In addition, astrocytes are thought to be important for supporting neighboring neurons by acting as energy providers and eliminators of excessive neurotransmitters. In this study, we examined the meaning of changes in the mitochondrial oxygen consumption rate (OCR) in primary mouse neuronal populations. By varying the medium constituents and using channel modulators, we found that pyruvate rather than lactate supported OCR levels and conferred on neurons resistance to glutamate‐mediated excitotoxicity. Under a pyruvate‐restricted condition, our OCR monitoring could detect excitotoxicity induced by glutamate at only 10 μM. The OCR monitoring also revealed the contribution of the N‐methyl‐D‐aspartate receptor and Na+/K+‐ATPase to the toxicity, which allowed evaluating spontaneous excitation. In addition, the OCR monitoring showed that astrocytes preferentially used glutamate, not glutamine, for a substrate of the tricarboxylic acid cycle. This mechanism may be coupled with astrocyte‐dependent protection of neurons from glutamate‐mediated excitotoxicity. These results suggest that OCR monitoring would provide a new powerful tool to analyze the mechanisms underlying neurotoxicity and protection against it. Neurons and astrocytes differentially respond to glutamate and glutamine. [ABSTRACT FROM AUTHOR]

[isolation and structure elucidation of four novel monoterpene lactones]. [ABSTRACT FROM AUTHOR]

Two new stilbenes (Ia) and (II) are isolated together with five known stilbenes and rotenoids. [ABSTRACT FROM AUTHOR]

The article presents two diagrams regarding the degradation of labdane diterpenes extracted from leonurus japonicus leaves.