Neuroprotective effects of INM-176 against lipopolysaccharide-induced neuronal injury.

Neuroinflammation plays a critical role in the etiology of chronic neurodegenerative diseases such as Alzheimer's disease. INM-176 is a standardized ethanolic extract of Angelica gigas, which has been traditionally used as a tonic to treat anemia. In the present study, we investigated whether INM-176 exhibits neuroprotective activities against lipopolysaccharide (LPS)-induced neuronal damage in vitro and in vivo. In primary microglial cells, INM-176 significantly inhibited LPS-induced nitric oxide release and expression of tumor necrosis factor-α and interleukin-1ß. The expression levels of inducible nitric oxide synthase and cylcooxygenase-2 in BV2 microglial cells were markedly upregulated by LPS, but this increased expression was counteracted by INM-176. LPS-mediated neuronal damage in an organotypic hippocampal slice culture was also attenuated by the administration of INM-176. In addition, LPS (1 µg/2 µl, i.c.v.)-induced cognitive dysfunction in mice, as determined by passive avoidance and Y-maze tasks, was significantly attenuated by the administration of INM-176. Furthermore, the activation of microglia or astrocytes by LPS in the hippocampal regions of mice was suppressed by INM-176. These results suggest that the neuroprotective and cognition ameliorating effects of INM-176 against LPS-induced damage are mediated, in part, by its anti-inflammatory activities.

Indirubin-3'-oxime inhibits inflammatory activation of rat brain microglia.

Microglial cells play critical roles in the immune and inflammatory responses of the brain. Under pathological conditions, the activation of microglia helps to restore brain homeostasis. However, chronic microglial activation endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. As such, regulators of microglial activation have been considered as potential therapeutic candidates to reduce the risk of neurodegeneration associated with neurodegenerative diseases, including Alzheimer's and, Parkinson's diseases. Indirubin-3'-oxime, a potent inhibitor of cyclin-dependent kinases and glycogen synthase kinase-3ß, has been shown to have neuroprotective potential. The specific aim of this study was to examine the efficacy of indirubin-3'-oxime in the repression of microglial activation. Indirubin-3'-oxime was shown to effectively inhibit lipopolysaccharide (LPS)-induced nitric oxide release from cultured rat brain microglia. This compound reduced the LPS-stimulated productions of tumor necrosis factor-α, interleukin-1ß, prostaglandin E(2), and intracellular reactive oxygen species and also effectively reduced LPS-elicited NF-κB activation. In organotypic hippocampal slice cultures, indirubin-3'-oxime blocked LPS-related hippocampal cell death. These results suggest that indirubin-3'-oxime provides neuroprotection by reducing the productions of various neurotoxic molecules in activated microglia.

Anti-inflammatory effects of crocin and crocetin in rat brain microglial cells.

Microglial cells play critical roles in the immune and inflammatory responses of the central nervous system (CNS). Under pathological conditions, the activation of microglia helps in restoring CNS homeostasis. However, chronic microglial activation endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. Thus, negative regulators of microglial activation have been considered as potential therapeutic candidates to target neurodegeneration, such as that observed in Alzheimer's and Parkinson's diseases. Crocin and crocetin, found in the fruits of gardenia and in the stigmas of saffron, have been considered for the treatment of various disorders in traditional oriental medicine. Crocin and crocetin have been reported to have diverse pharmacological functions, such as anti-hyperlipidemic, anti-atherosclerotic, and anti-cancer effects. Specifically, the neuroprotective potential of crocetin derivatives has previously been demonstrated. The specific aim of this study was to examine whether crocin or crocetin represses microglial activation. Crocin and crocetin were shown to be effective in the inhibition of LPS-induced nitric oxide (NO) release from cultured rat brain microglial cells. These compounds reduced the LPS-stimulated productions of tumor necrosis factor-α, interleukin-1ß, and intracellular reactive oxygen species. The compounds also effectively reduced LPS-elicited NF-κB activation. In addition, crocin reduced NO release from microglia stimulated with interferon-γ and amyloid-ß. In organotypic hippocampal slice cultures, both crocin and crocetin blocked the effect of LPS on hippocampal cell death. These results suggest that crocin and crocetin provide neuroprotection by reducing the production of various neurotoxic molecules from activated microglia.

Genipin inhibits the inflammatory response of rat brain microglial cells.

Microglia are the prime effectors in immune and inflammatory responses of the central nervous system (CNS). Under pathological conditions, the activation of these cells helps restore CNS homeostasis. However, chronic microglial activation endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. Thus, negative regulators of microglial activation have been considered as potential therapeutic candidates to target neurodegeneration, such as that in Alzheimer's and Parkinson's diseases. Genipin, the aglycon of geniposide found in gardenia fruit has long been considered for treatment of various disorders in traditional oriental medicine. Genipin has recently been reported to have diverse pharmacological functions, such as antimicrobial, antitumor, and anti-inflammatory effects. The specific aim of this study was to examine whether genipin represses brain microglial activation. Genipin was effective at inhibiting LPS-induced nitric oxide (NO) release from cultured rat brain microglial cells. Genipin reduced the LPS-stimulated production of tumor necrosis factor-alpha, interleukin-1beta, prostaglandin E(2), intracellular reactive oxygen species, and NF-kappaB activation. In addition, genipin reduced NO release from microglia stimulated with interferon-gamma and amyloid-beta. Both pretreatment and post-treatment of genipin to LPS-stimulated microglia were effective at decreasing NO release. Furthermore, genipin effectively inhibited microglial activation in a mouse model of brain inflammation. These results suggest that genipin provide neuroprotection by reducing the production of various neurotoxic molecules from activated microglia.

Chunghyuldan attenuates brain microglial inflammatory response.

Microglial cells are the prime effectors in immune and inflammatory responses of the central nervous system (CNS). During pathological conditions, the activation of these cells helps restore CNS homeostasis. However, chronic microglial activation endangers neuronal survival through the release of various proinflammatory molecules and neurotoxins. Thus, negative regulators of microglial activation have been considered as potential therapeutic candidates to target stroke and neurodegenerative diseases. Chunghyuldan, a combinatorial drug consisting of Scutellariae Radix, Coptidis Rhizoma, Phellodendri Cortex, Gardeniae Fructus, and Rhei Rhizoma, has an inhibitory effect on stroke recurrence in patients with small-vessel disease. It has also been reported to confer antihypertensive, antihyperlipidemic, and antiinflammatory effects. The aim of this study was to examine whether Chunghyuldan suppresses microglial activation. Chunghyuldan was effective at inhibiting LPS-induced nitric oxide (NO) release from rat brain microglia. Real-time reverse transcriptase PCR analysis revealed that pretreatment of rat brain microglia with Chunghyuldan attenuated the LPS-induced expression of mRNAs encoding inducible NO synthase, tumor necrosis factor (TNF)-alpha, interleukin-1beta, and cyclooxygenase-2. In rat brain microglia, Chunghyuldan reduced the LPS-stimulated production of TNF-alpha and prostaglandin E2. In addition, Chunghyuldan significantly decreased LPS-induced phosphorylation of the ERK1/2 and p38 signaling proteins. These results suggest that Chunghyuldan provide neuroprotection by reducing the release of various proinflammatory molecules from activated microglia.

Rapid Molecular Detection of Escherichia coli O157:H7 / 감염

BACKGROUND: Sorbitol fermenting Escherichia coli O157 were reported. And E. coli O157:H7 produce various Shiga toxin (Stx) such as Stx1, Stx2, or variants of Stx2. In this study, we tried to establish laboratory methods that detect E. coli O157:H7 quickly and precisely by analyzing sensitivity of colony hybridization test and PCR technique. METHODS: Stx1-producing E. coli ATCC 43890, Stx2-producing E. coli ATCC 43889, and Stx2vha- producing E. coli ATCC 51435 were tested. Three strains of E. coli were diluted with 0.1 g of diarrheal stools from 107 CFU to 101 CFU respectively. The stool samples were incubated overnight in MacConkey agar plates. A mean of 63 colonies were hybridized by stx1- and stx2-specific oligonucleotide probes. PCR for stx1 gene and stx2 gene was done after overnight- incubation of stool samples in the LB broth with vancomycin (6 ug/mL). Positive colonies by colony hybridization were confirmed by PCR for stx1 gene and stx2 gene. RESULTS: Colony hybridization test could detect Stx1-producing E. coli at 103 CFU per 0.1 g of stool, Stx2-producing E. coli at 105 CFU per 0.1 g of stool, and Stx2vha-producing E. coli at 104 CFU per 0.1 g of stool. PCR technique after enrichment in LB broth with vancomycin (6 ug/mL) could detect stx1-, stx2-, and stx2vha-containing E. coli at 10 CFU per 0.1 g of stool respectively. CONCLUSOIN: A combination of colony hybridization and PCR after enrichment in broth with vancomycin (6 ug/mL) is useful for the rapid and precise diagnosis of infections of Shiga toxin-producing E. coli O157:H7.