Safety, tolerability of ES16001, a novel varicella zoster virus reactivation inhibitor, in healthy adults.

PURPOSE: Herpes zoster (HZ), or shingles, is a clinical syndrome resulting from the reactivation of latent varicella zoster virus (VZV) within the sensory ganglia. We evaluated the safety and tolerability of ES16001 (ethanol extract of Elaeocarpus sylvestris var. ellipticus), a novel inhibitor of varicella zoster virus reactivation in healthy adults. METHOD: Single-center, randomized, double-blind, placebo-controlled, single and multiple ascending dose (SAD and MAD, respectively) studies were conducted in 20- to 45-year-old healthy adults without chronic disease. In the SAD study (n = 32), subjects randomly received a single oral dose of 240, 480, 960, or 1440 mg ES16001 or a placebo. In the MAD study (n = 16), subjects randomly received once daily doses of 480 or 960 mg ES16001 or a placebo for 5 days. The safety and tolerability of the drug were evaluated by monitoring participants' treatment emergent adverse events (TEAEs) and vital signs, electrocardiograms (ECGs), physical examinations, and clinical laboratory tests. RESULTS: In the SAD study, 11 adverse reactions were seen in 5 subjects, and in the MAD study, 8 adverse reactions were seen in 6 subjects. All adverse reactions were mild, and no serious adverse reactions occurred. The most common adverse reaction was an increase in alanine aminotransferase (ALT), but all test values were in the clinically non-significant range, and their clinical significance was judged to be small considering the fact that most of the test values returned to normal immediately after the end of drug administration. CONCLUSION: ES16001 has good safety and tolerability when administered both once and repeatedly to healthy subjects. Further research is needed to identify any possible drug-induced hepatotoxicity, which appears infrequently. Our findings provide a rationale for further clinical investigations of ES16001 for the prevention of HZ. TRIAL REGISTRATION: CRIS, KCT0006066. Registered 7 April 2021-Retrospectively registered, https://cris.nih.go.kr/cris/search/detailSearch.do/19071 ).

Synthesis of Clovamide Analogues That Inhibit NO Production in Activated BV-2 Microglial Cells.

A series of methyl ester of clovamide analogues, where the hydroxyl group of catechol moiety in caffeic acid and L-3,4-dihydroxyphenylalanine (L-dopa) was replaced with various functional groups, were synthesized and their inhibitory effects on nitric oxide (NO) production and inducible NO synthase (iNOS) expression in lipopolysaccharide (LPS)-induced BV2 cells were tested. Among the synthesized compounds, 3,5-ditrifluoromethyl analogue 9l (IC50=2.8 µM) exhibited a potency about 26.3 times greater than that of the parent compound 9a (IC50=73.6 µM) and suppressed NO production dose-dependently without cytotoxicity. Compound 9l also inhibited iNOS expression in LPS-induced BV2 cells at 2.5, 5 and 10 µM concentrations. These results suggested that the dihydroxyl group of catechol moiety in caffeic acid unit is not essential for the suppression of NO production and that 9l has potential as a potent inhibitor of NO production.

Attenuation of neuroinflammatory responses and behavioral deficits by Ligusticum officinale (Makino) Kitag in stimulated microglia and MPTP-induced mouse model of Parkinson's disease.

ETHNOPHARMACOLOGICAL RELEVANCE: Ligusticum officinale (Makino) Kitag (L. officinale) is one of the important traditional herbs used in traditional Oriental medicine for the treatment of various disorders including pain and inflammation. However, there is limited scientific basis for its activity and mechanism in brain inflammation. AIM OF THE STUDY: This study aimed to evaluate the effects of L. officinale on microglia-mediated neuroinflammation and behavioral impairments using in vitro cellular and in vivo mouse model of PD, as well as investigate the molecular mechanisms involved including the finger printing analysis of its ethanol extract. MATERIALS AND METHODS: Lipopolysaccharide (LPS) was used to stimulate BV-2 microglial cells. The changes in neuroinflammatory expressional levels were measured by Western blotting and immunofluorescence techniques. 1-methyl-4 phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-intoxicated mice model of PD was developed to evaluate the behavioral impairments and the brain tissues were used for immunohistochemical studies. High performance liquid chromatography (HPLC) technique was performed for finger printing analysis of L. officinale extract used in the study. RESULTS: L. officinale significantly attenuated the LPS-stimulated increase in inflammatory mediators in BV-2 cells. L. officinale also inhibited the LPS-induced activation of nuclear factor-kappa beta by blocking the degradation of IκB-α and suppressing the increase in p38-mitogen-activated protein kinase phosphorylation in BV-2 cells. Furthermore, L. officinale exhibited significant antioxidant properties by inhibiting the 1-diphenyl-2-picrylhydrazyl radicals. An in vivo evaluation in MPTP (20mg/kg, four times, 1 day, i.p.) intoxicated mice resulted in brain microglial activation and significant behavioral deficits. Prophylactic treatment with L. officinale prevented microglial activation and attenuated PD-like behavioral changes as assessed by the pole test. HPLC finger printing analysis revealed that L. officinale extract contained ferulic acid (FA) as one of the major constituents compared with reference standard. FA also inhibited the LPS-stimulated excessive release of NO and suppressed the increased the expressional levels of proinflammatory mediators in BV-2 microglia. CONCLUSIONS: The findings observed in this study indicated that L. officinale extract significantly attenuated the neuroinflammatory processes in stimulated microglia and restored the behavioral impairments in a mouse model of PD providing a scientific basis for its traditional claims.

Attenuation of inflammatory-mediated neurotoxicity by Saururus chinensis extract in LPS-induced BV-2 microglia cells via regulation of NF-κB signaling and anti-oxidant properties.

BACKGROUND: A Saururus chinensis Baill (SC) has been used by Native Americans, early colonists and practitioners of Korean traditional medicine for treating several diseases including cancer, rheumatoid arthritis and edema. The objective of this study was to evaluate the effects of SC extract in lipopolysaccharide (LPS)-stimulated neuroinflammatory responses in BV-2 microglial cells. METHODS: The effects of SC on the LPS-induced neuroinflammatory responses in BV-2 microglial cells were assessed by Western blotting, RT-PCR and immunofluorescence labeling techniques. DPPH and alkyl radical scavenging assay was performed to evaluate the anti-oxidant effects. Comparisons between groups were analyzed using one-way analysis of variance followed by Dunnett's multiple comparisons test using GraphPad Prism V5.01 software. RESULTS: Pre-treatment with SC extract (1, 5 and 10 µg/mL) significantly (p < 0.001 at 10 µg/mL) and concentration dependently inhibited LPS-induced production of nitric oxide (NO), inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) and suppressed the inflammatory cytokine levels such as tumor necrosis factor-alpha and interleukin (IL)-6 in BV-2 microglial cells (p < 0.001 at 10 µg/mL). Further, SC suppressed the nuclear factor-kappa B (NF-κB) activation by blocking the degradation of IκB-α. SC also exhibited profound anti-oxidant effects by scavenging 1, 1-diphenyl-2-picrylhydrazyl (DPPH) (IC50: 0.055 mg/mL) and alkyl radicals (IC50: 0.349 mg/mL). High performance liquid chromatography finger printing analysis of SC revealed quercetin (QCT) as one of the major constituents compared with reference standard. QCT also inhibited the excessive release of NO, and inhibited the increased expressional levels of IL-6, iNOS and COX-2 in LPS-stimulated BV-2 cells. CONCLUSIONS: Our results indicated that SC inhibited the LPS-stimulated neuroinflammatory responses in BV-2 microglia via regulation of NF-κB signaling. The antioxidant active constituents of SC might be partly involved in delivering such effects. Based on the traditional claims and our present results SC can be potentially used in treating inflammatory-mediated neurodegenerative diseases.

ß-Asarone (cis-2,4,5-trimethoxy-1-allyl phenyl), attenuates pro-inflammatory mediators by inhibiting NF-κB signaling and the JNK pathway in LPS activated BV-2 microglia cells.

Acorus species contains diverse pharmacologically active phytochemicals including α-asarone, ß-asarone, and eugenol. We determined if ß-asarone isolated from Acorus gramineus (AG) Solander would be efficacious in protecting BV-2 microglia cells from lipopolysaccharide (LPS)-induced stress signaling. BV-2 microglial cells were pretreated with an AG ethanol extract (1, 10, and 100 µg/mL) or ß-asarone (10, 50, and 100 µM) prior to exposure to LPS (100 ng/mL). AG and ß-asarone inhibited LPS-induced production of nitric oxide in a dose-dependent manner. The mRNA and protein levels of inducible nitric oxide synthase and cyclooxygenase-2 also decreased dose dependently following AG and ß-asarone treatments. Immunostaining and immunoblot studies revealed that ß-asarone also suppressed nuclear factor (NF)-κB activation by blocking IkB degradation. Further mechanistic studies revealed that ß-asarone acted through the JNK/MAPK pathway. Taken together, our findings demonstrate that ß-asarone exhibits anti-inflammatory effects by suppressing the production of pro-inflammatory mediators through NF-κB signaling and the JNK pathways in activated microglial cells and might be developed as a promising candidate to treat various neuroinflammatory diseases.

Traditional Korean East Asian medicines and herbal formulations for cognitive impairment.

Hanbang, the Traditional Korean Medicine (TKM), is an inseparable component of Korean culture both within the country, and further afield. Korean traditional herbs have been used medicinally to treat sickness and injury for thousands of years. Oriental medicine reflects our ancestor's wisdom and experience, and as the elderly population in Korea is rapidly increasing, so is the importance of their health problems. The proportion of the population who are over 65 years of age is expected to increase to 24.3% by 2031. Cognitive impairment is common with increasing age, and efforts are made to retain and restore the cognition ability of the elderly. Herbal materials have been considered for this purpose because of their low adverse effects and their cognitive-enhancing or anti-dementia activities. Herbal materials are reported to contain several active compounds that have effects on cognitive function. Here, we enumerate evidence linking TKMs which have shown benefits in memory improvements. Moreover, we have also listed Korean herbal formulations which have been the subject of scientific reports relating to memory improvement.

Gastrodin protects apoptotic dopaminergic neurons in a toxin-induced Parkinson's disease model.

Gastrodia elata (GE) Blume is one of the most important traditional plants in Oriental countries and has been used for centuries to improve various conditions. The phenolic glucoside gastrodin is an active constituent of GE. The aim of this study was to investigate the neuroprotective role of gastrodin in 1-methyl-4-phenylpyridinium (MPP(+))/1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine- (MPTP) induced human dopaminergic SH-SY5Y cells and mouse model of Parkinson's disease (PD), respectively. Gastrodin significantly and dose dependently protected dopaminergic neurons against neurotoxicity through regulating free radicals, Bax/Bcl-2 mRNA, caspase-3, and cleaved poly(ADP-ribose) polymerase (PARP) in SH-SY5Y cells stressed with MPP(+). Gastrodin also showed neuroprotective effects in the subchronic MPTP mouse PD model by ameliorating bradykinesia and motor impairment in the pole and rotarod tests, respectively. Consistent with this finding, gastrodin prevented dopamine depletion and reduced reactive astrogliosis caused by MPTP as assessed by immunohistochemistry and immunoblotting in the substantiae nigrae and striatata of mice. Moreover, gastrodin was also effective in preventing neuronal apoptosis by attenuating antioxidant and antiapoptotic activities in these brain areas. These results strongly suggest that gastrodin has protective effects in experimental PD models and that it may be developed as a clinical candidate to ameliorate PD symptoms.

Regulation of microglia activity by glaucocalyxin-A: attenuation of lipopolysaccharide-stimulated neuroinflammation through NF-κB and p38 MAPK signaling pathways.

Microglial cells are the resident macrophages and intrinsic arm of the central nervous system innate immune defense. Microglial cells become activated in response to injury, infection, environmental toxins, and other stimuli that threaten neuronal survival. Therefore, regulating microglial activation may have therapeutic benefits that lead to alleviating the progression of inflammatory-mediated neurodegeneration. In the present study, we investigated the effect of glaucocalyxin A (GLA) isolated from Rabdosia japonica on the production of pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated primary microglia and BV-2 cells. GLA significantly inhibited LPS-induced production of nitric oxide and reversed the morphological changes in primary microglia. Further, GLA suppressed expression of inducible nitric oxide synthase and cyclooxygenase-2 dose-dependently at the mRNA and protein levels. The production of proinflammatory cytokines such as tumor necrosis factor-α, interleukin-1ß (IL)-1ß, and IL-6 were inhibited by suppressing their transcriptional activity. Furthermore, GLA suppressed nuclear factor-κB activation by blocking degradation of IκB-α and inhibited the induction of lipocalin-2 expression in LPS-stimulated BV-2 cells. Mechanistic study revealed that the inhibitory effects of GLA were accompanied by blocking the p38 mitogen activated protein kinase signaling pathway in activated microglia. In conclusion, given that microglial activation contributes to the pathogenesis of neurodegenerative diseases, GLA could be developed as a potential therapeutic agent for treating microglia-mediated neuroinflammatory diseases.

The role of bioactive compounds on the promotion of neurite outgrowth.

Neurite loss is one of the cardinal features of neuronal injury. Apart from neuroprotection, reorganization of the lost neuronal network in the injured brain is necessary for the restoration of normal physiological functions. Neuritogenic activity of endogenous molecules in the brain such as nerve growth factor is well documented and supported by scientific studies which show innumerable compounds having neurite outgrowth activity from natural sources. Since the damaged brain lacks the reconstructive capacity, more efforts in research are focused on the identification of compounds that promote the reformation of neuronal networks. An abundancy of natural resources along with the corresponding activity profiles have shown promising results in the field of neuroscience. Recently, importance has also been placed on understanding neurite formation by natural products in relation to neuronal injury. Arrays of natural herbal products having plentiful active constituents have been found to enhance neurite outgrowth. They act synergistically with neurotrophic factors to promote neuritogenesis in the diseased brain. Therefore use of natural products for neuroregeneration provides new insights in drug development for treating neuronal injury. In this study, various compounds from natural sources with potential neurite outgrowth activity are reviewed in experimental models.

Modulation of LPS-stimulated neuroinflammation in BV-2 microglia by Gastrodia elata: 4-hydroxybenzyl alcohol is the bioactive candidate.

ETHNOPHARMACOLOGICAL RELEVANCE: Gastrodia elata Blume (Orchidaceae, GE) a traditional plant in Oriental countries is known for its enormous benefits to treat headaches, dizziness, vertigo and convulsive illnesses. In the present study, the ethnopharmacological role of GE in neuroinflammation mediated by activated microglia and the mechanisms underlying were reported. MATERIALS AND METHODS: BV-2 microglia activated by lipopolysaccharide (LPS) was employed and the effects of GE on corresponding neuroinflammatory parameters were assessed. RESULTS: GE extract inhibited LPS-stimulated production of inflammatory cytokines and down regulated the c-Jun NH(2)-Terminal Kinase (JNK) and nuclear factor-kappa B (NF-κB) signaling pathways, which are known to be involved in neuroinflammation. Further, inhibition of NO and iNOS by 4-hydroxybenzyl alcohol (4-HBA), one of the active constituent of GE in LPS-stimulated BV-2 cells suggest that 4-HBA might be the bioactive candidate. CONCLUSION: GE extract and its active constituent 4-HBA could be further exploited to mitigate microglial activation and may be developed as a new therapeutic remedy in treating various neuroinflammatory diseases.

Protective effect of Chrysanthemum indicum Linne against 1-methyl-4-phenylpridinium ion and lipopolysaccharide-induced cytotoxicity in cellular model of Parkinson's disease.

Chrysanthemum indicum Linn. (CI) has been used in Oriental medicine for several centuries. In the present study, the effect of CI extract was evaluated against 1-methyl-4-phenylpridinium ion (MPP(+))-induced damage in SH-SY5Y cells and lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. Cell viability, oxidative damage, reactive oxygen species, expression of Bcl-2/Bax, and poly (ADP-ribose) polymerase (PARP) proteolysis were evaluated using SH-SY5Y cells. Production of iNOS, prostaglandin E(2), and pro-inflammatory cytokines like tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, interleukin (IL)-6, expression of cyclooxygenase type-2 (COX-2) and type-1 (COX-1) were examined in activated BV-2 microglia. At 1, 10 and 100 µg, CI inhibited cell loss, decreased the reactive oxygen species production, regulated the Bax/Bcl-2 ratio and inhibited PARP proteolysis in MPP(+)-induced SH-SY5Y cells. Furthermore, CI suppressed the production of prostaglandin E(2,) expression of cyclooxygenase type-2 (COX-2), blocked IκB-α degradation and activation of NF-κB p65 in BV-2 cells in a dose-dependent manner. The molecular mechanisms involved by CI might involve its inhibitory actions both on neuronal apoptosis and neuroinflammatory NF-κB/IκB-α signaling pathway. The present investigation scientifically supports the long history and safe usage of CI as an important functional food with potential benefits in ameliorating deleterious conditions seen in PD.