α-Asarone attenuates microglia-mediated neuroinflammation by inhibiting NF kappa B activation and mitigates MPTP-induced behavioral deficits in a mouse model of Parkinson's disease.

The selective loss of dopaminergic neurons in Parkinson's disease (PD) is associated with microglial activation. Therefore, the importance of early therapeutic intervention to inhibit microglial activation would be an effective strategy to alleviate the progression of PD. α-Asarone, an active compound found in Araceae and Annonaceae plant species has been used to improve various disease conditions including central nervous system disorders. In the present study the in vitro and in vivo therapeutic effects of α-asarone isolated from the rhizome of Acorus gramineus Solander was evaluated on microglia-mediated neuroinflammation and neuroprotection. Lipopolysaccharide (LPS)-stimulated BV-2 microglial cells were used to evaluate in vitro effects. 1-methyl-4 phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced mouse model of PD was developed to study the neuroprotective effects of α-asarone in vivo. The results indicated that α-asarone significantly attenuated the LPS-stimulated increase in neuroinflammatory responses and suppressed pro-inflammatory cytokine production in BV-2 cells. Mechanistic study revealed that α-asarone inhibited the LPS-stimulated activation via regulation of nuclear factor kappa-B by blocking degradation of inhibitor kappa B-alpha signaling in BV-2 microglial cells. In in vivo studies, MPTP intoxication to mice resulted in brain microglial activation and significant behavioral deficits. Prophylactic treatment with α-asarone suppressed microglial activation and attenuated PD-like behavioral impairments as assessed by the Y-maze and pole tests. Taken together, these data demonstrate that α-asarone is a promising neuroprotective agent that should be further evaluated and developed for future prevention and treatment of microglia-mediated neuroinflammatory conditions including PD.

Kim BW ，Koppula S ，Kumar H ，Park JY ，Kim IW ，More SV ，Kim IS ，Han SD ，Kim SK ，Yoon SH ，Choi DK ... -  《-》

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

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. 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. 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. 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. 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.

Kim BW ，Koppula S ，Park SY ，Kim YS ，Park PJ ，Lim JH ，Kim IS ，Choi DK ... -  《-》

Acorus gramineus inhibits microglia mediated neuroinflammation and prevents neurotoxicity in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of Parkinson's disease.

Acorus gramineus Solander (Acoraceae, AG), is a widely distributed plant in Asian countries. Rhizome part of this plant has long been used as a traditional medicine for treating various symptoms including central nervous system (CNS) disorders. The anti-neuroinflammatory effect of AG aqueous extract was investigated using in vitro cellular and in vivo Parkinson's disease (PD) mouse model. Lipopolysaccharide (LPS) is used to stimulate BV-2 microglial cells in vitro and the changes in neuroinflammatory expressional levels were measured using ELISA, Western blotting, RT-PCR and immunofluorescence techniques. In in vivo experiments, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated mouse model of PD was developed followed by immunohistochemical analysis of specific brain tissues. LPS-stimulation to BV-2 cells increased the production of nitric oxide (NO) and proinflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1β. Pretreatment with AG extract inhibited the increased levels of NO and pro-inflammatory cytokines in LPS-stimulated BV-2 cells. Mechanistic study revealed that AG acts via the regulation of nuclear factor kappa B (NF-κB), mitogen-activated protein kinases (MAPKs) and TRIF-dependent signaling pathways. Further, AG protected MPTP-induced neuronal cell death and inhibited neuroinflammation in vivo. Our results indicated that AG extract exerted anti-neuroinflammatory effects against activated microglia mediated insults through multiple signaling pathways and prevented in vivo neuronal cell death in mouse model of PD substantiating the traditional claims for its use in CNS disorders.

Jiang J ，Kim JJ ，Kim DY ，Kim MK ，Oh NH ，Koppula S ，Park PJ ，Choi DK ，Shin YK ，Kim IH ，Kang TB ，Lee KH ... -  《-》

β-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, β-asarone, and eugenol. We determined if β-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 β-asarone (10, 50, and 100 μM) prior to exposure to LPS (100 ng/mL). AG and β-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 β-asarone treatments. Immunostaining and immunoblot studies revealed that β-asarone also suppressed nuclear factor (NF)-κB activation by blocking IkB degradation. Further mechanistic studies revealed that β-asarone acted through the JNK/MAPK pathway. Taken together, our findings demonstrate that β-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.

Lim HW ，Kumar H ，Kim BW ，More SV ，Kim IW ，Park JI ，Park SY ，Kim SK ，Choi DK ... -  《-》

Anti-neuroinflammatory effects of DPTP, a novel synthetic clovamide derivative in in vitro and in vivo model of neuroinflammation.

Neuroinflammation is one of the critical pathological mechanisms influencing various neurodegenerative disorders. Most of the neurodegenerative diseases involve over-activation of microglial cells contributing to the demise of neurons. The objective of the current study is to evaluate the anti-inflammatory effect of novel synthetic clovamide derivative on the suppression of microglial activation in an in vitro and in vivo model of neuroinflammation. We have used lipopolysaccharide (LPS) to induce an inflammatory response in murine BV-2 microglial cells. Molecular tools like immunocytochemistry and immunoblotting were used to study the activity of novel synthetic clovamide derivative to inhibit inflammation induced by LPS in microglial cells. In in vivo experiments, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxicated mouse model of neuroinflammation was developed to investigate the anti-neuroinflammatory effects of DPTP [3-(3,4-Dihydroxy-phenyl)-2-[4-(3-trifluoromethylphenyl)-but-2-enoylamino]-propionic acid methyl ester]. DPTP was observed to reduce the proinflammatory response in BV-2 cells induced by LPS. Further investigation revealed that DPTP attenuated phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK), which was accompanied by a decrease in nuclear translocation of nuclear factor-κB (NF-κB) in LPS-treated BV2 microglia. Moreover, prophylactic treatment with DPTP (20mg/kg) for 7 days suppressed MPTP induced glial activation and behavioral impairment. Overall, our findings suggested that, DPTP exerts anti-neuroinflammatory effects against activated microglia in an in vitro and in vivo model and hence might be a promising therapeutic agent for alleviating the evolvement of neurodegenerative diseases associated with microglial activation.

Lim HW ，Park JI ，More SV ，Park JY ，Kim BW ，Jeon SB ，Yun YS ，Park EJ ，Yoon SH ，Choi DK ... -  《-》