Comprehensive analysis of the dynamic changes of volatile and non-volatile metabolites in boletus edulis during processing by HS-SPME-GC-MS and UPLC-MS/MS analysis.

In order to investigate the dynamic changes of flavor compounds, Ultra Performance Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS/MS) combined with Headspace Solid Phase Microextraction Gas Chromatography Mass Spectrometry (HS-SPME-GC-MS) was used to detect the metabolites in different drying processes. A total of 80 volatile compounds and 1319 non-volatile compounds were identified. The trend in the changes of C-8 compounds and sulfur-containing compounds were generally consistent with the trend of key enzyme activities. 479 differential metabolites were identified and revealed that metabolic profiles of compounds in Boletus edulis were altered with increased organic acids and derivatives and lipids and lipid-like molecules. Fatty acids and amino acids were transformed into volatile compounds under the action of enzymes, which played a significant role in the formation of the distinctive flavor of Boletus edulis. Our study provided a theoretical support for fully comprehending the formation mechanism of flavor from Boletus edulis during drying processes.

A GAD1 inhibitor suppresses osteosarcoma growth through the Wnt/ß-catenin signaling pathway.

Background: As a marker of the GABAergic system, the expression of glutamate decarboxylase 1 (GAD1) is mainly restricted to the central nervous system. Emerging studies have shown that aberrant expression of GAD1 in tumor tissues may promote tumor cell growth. The role of GAD1 in the development of osteosarcoma (OS) remains unclear, so this study sought to investigate the expression status of GAD1 and the effect of its specific inhibitor 3-mercaptopropionic acid (3-MPA) on OS. Methods: The R2 database was used to analyze the relationship between the expression of GAD1 and clinical prognosis in OS patients. Immunohistochemistry was used to compare the expression profile of GAD1 between OS and matched neighboring tissues. The potential antitumor effects of 3-MPA on cell viability, colony formation and the cell cycle were examined. Moreover, the in vivo effect of 3-MPA on tumor growth was investigated using tumor-bearing nude mice. Results: The expression level of GAD1 was aberrantly upregulated in OS tissues, but almost no expression of GAD1 was found in matched neighboring tissues. Western blotting analyses showed upregulation of GAD1 in OS cells compared to human osteoblast cells. In vitro and in vivo, 3-MPA significantly suppressed the growth of OS. Regarding the mechanism, 3-MPA inhibited ß-catenin and cyclin D1 in OS cells, thereby inactivating the Wnt/ß-catenin pathway. Conclusions: OS displays increased expression of the GABAergic neuronal marker GAD1, and 3-MPA significantly reduces OS growth by inhibiting the Wnt/ß-catenin pathway.

Bacterial battle against acidity.

The Earth is home to environments characterized by low pH, including the gastrointestinal tract of vertebrates and large areas of acidic soil. Most bacteria are neutralophiles, but can survive fluctuations in pH. Herein, we review how Escherichia, Salmonella, Helicobacter, Brucella, and other acid-resistant Gram-negative bacteria adapt to acidic environments. We discuss the constitutive and inducible defense mechanisms that promote survival, including proton-consuming or ammonia-producing processes, cellular remodeling affecting membranes and chaperones, and chemotaxis. We provide insights into how Gram-negative bacteria sense environmental acidity using membrane-integrated and cytosolic pH sensors. Finally, we address in more detail the powerful proton-consuming decarboxylase systems by examining the phylogeny of their regulatory components and their collective functionality in a population.

Central Endothelin-1 Confers Analgesia by Triggering Spinal Neuronal Histone Deacetylase 5 (HDAC5) Nuclear Exclusion in Peripheral Neuropathic Pain in Mice.

The rationale of spinal administration of endothelin-1(ET-1) mediated anti-nociceptive effect has not been elucidated. ET-1 is reported to promote nuclear effluxion of histone deacetylase 5 (HDAC5) in myocytes, and spinal HDAC5 is implicated in modulation of pain processing. In this study, we aimed to investigate whether central ET-1 plays an anti-nociceptive role by facilitating spinal HDAC5 nuclear shuttling under neuropathic pain. Here, we demonstrate that upregulating spinal ET-1 attenuated the nociception induced by partial sciatic nerve ligation surgery and this analgesic effect mediated by ET-1 was attenuated by intrathecal injection of endothelin A receptor selective inhibitor (BQ123) or by blocking the exportation of nuclear HDAC5 by adeno-associated viruses targeting neuronal HDAC5 (AVV-HDAC5 S259/498A Mutant). Notably, ET-1 administration increased spinal glutamate acid decarboxylases (GAD65/67) expression via initiating HDAC5 nuclear exportation and increased the acetylation of histone 3 at lysine 9 (Acetyl-H3K9) in the promotor regions of spinal Gad1 and Gad2 genes. This was reversed by blocking endothelin A receptor function or by inhibiting the spinal neuronal nuclear exportation of HDAC5. Therefore, inducing spinal GABAergic neuronal HDAC5 nuclear exportation may be a novel therapeutic approach for managing neuropathic pain. PERSPECTIVE: Neuropathic pain is intractable in a clinical setting, and epigenetic regulation is considered to contribute to this processing. Characterizing the anti-nociceptive effect of ET-1 and investigating the associated epigenetic mechanisms in animal models may lead to the development of new therapeutic strategies and targets for treating neuropathic pain.

Enhanced GABAergic Immunoreactivity in Hippocampal Neurons and Astroglia of Multiple Sclerosis Patients.

Cognitive dysfunction occurs frequently in multiple sclerosis (MS). Research suggests that hippocampal lesions and GABAergic neurotransmitter changes contribute to cognitive dysfunction. In the present study, we aim to determine the cellular changes in GABAergic expression in MS hippocampus related to inflammation and demyelination. To this end, the presence and inflammatory activity of demyelinating lesions was determined by immunohistochemistry in human postmortem hippocampal tissue of 15 MS patients and 9 control subjects. Subsequently, GABAergic cells were visualized using parvalbumin (PV) and glutamate acid decarboxylase 67 (GAD67) markers. Fluorescent colabeling was performed of GAD67 with neuronal nuclei, PV, astrocytic glial fibrillary acidic protein, or vesicular GABA transporter. We observed increased GAD67-positive (GAD67+) neuron and synapse numbers in the CA1 of MS patients with active hippocampal lesions, not due to neurogenesis. The number and size of PV-positive neurons remained unchanged. GAD67+ astrocytes were more numerous in hippocampal white matter than grey matter lesions. Additionally, in MS patients with active hippocampal lesions GAD67+ astrocyte surface area was increased. Disturbed cognition was most prevalent in MS patients with active hippocampal lesions. Summarizing, increased GAD67 immunoreactivity occurs in neurons and astrocytes and relates to hippocampal inflammation and possibly disturbed cognition in MS.

Dynamic changes of glutamate during cerebral ischemia in the cortex of cynomolgus monkeys / 第三军医大学学报

Objective To explore the dynamic changes of glutamate in the cortex of cynomolgus monkeys during cerebral ischemia.Methods Proximal M1 segment of middle cerebral artery (MCA) was occluded for 1 h in 3 young cynomolgus monkeys (7.3 ± 1.5 years old) to induce cerebral ischemia.Magnetic resonance imaging and neurologic deficit scoring were used to evaluate the ischemia and observe the manifestations,respectively.Fast Analytical Sensing Technology (FAST) was applied to record the content of cortex glutamate in the same site of ipsilateral primary motor cortex in the periods of pre-,during,and post-occlusion,and at 1 and 2 weeks after surgery.Results Compared with pre-occlusion,the content of glutamate was increased significantly in the process of occluding in the MCA M1 (P =0.003);No significant difference was observed in the content during occluding and post-occlusion (P--0.877).The content in the first week was decreased obviously as compared with post-occlusion (P--0.004),but it showed no statistical difference with that in the second week (P =0.085).Conclusion Cerebral ischemia may potentially accelerate the extra-cellular glutamate release in the cortex,but reperfusion may ameliorate or balance off the glutamate release.

Glutamate Decarboxylase 1 Overexpression as a Poor Prognostic Factor in Patients with Nasopharyngeal Carcinoma.

Background: Glutamate decarboxylase 1 (GAD1) which serves as a rate-limiting enzyme involving in the production of γ-aminobutyric acid (GABA), exists in the GABAergic neurons in the central nervous system (CNS). Little is known about the relevance of GAD1 to nasopharyngeal carcinoma (NPC). Through data mining on a data set derived from a published transcriptome database, this study first identified GAD1 as a differentially upregulated gene in NPC. We aimed to evaluate GAD1 expression and its prognostic effect on patients with early and locoregionally advanced NPC. Methods: We evaluated GAD1 immunohistochemistry and performed an H-score analysis on biopsy specimens from 124 patients with nonmetastasized NPC receiving treatment. GAD1 overexpression was defined as an H score higher than the median value. The findings of such an analysis are correlated with clinicopathological behaviors and survival rates, namely disease-specific survival (DSS), distant-metastasis-free survival (DMeFS), and local recurrence-free survival (LRFS) rates. Results: GAD1 overexpression was significantly associated with an increase in the primary tumor status (p < 0.001) and American Joint Committee on Cancer (AJCC) stages III-IV (p = 0.002) and was a univariate predictor of adverse outcomes of DSS (p = 0.002), DMeFS (p < 0.0001), and LRFS (p = 0.001). In the multivariate comparison, in addition to advanced AJCC stages III-IV, GAD1 overexpression remained an independent prognosticator of short DSS (p = 0.004, hazard ratio = 2.234), DMeFS (p < 0.001, hazard ratio = 4.218), and LRFS (p = 0.013, hazard ratio = 2.441) rates. Conclusions: Our data reveal that GAD1 overexpression was correlated with advanced disease status and may thus be a critical prognostic indicator of poor outcomes in NPC and a potential therapeutic target to facilitate the development of effective treatment modalities.

Neuroprotective Effect of Ginkgolides on Cultured Dorsal Root Ganglion Neurons with Neurotoxicity Induced by Glutamate / 天津医药

Objective:To determine the neuroprotective effect of ginkgolides(Gin)on cultured rat embryos dorsal root ganglion(DRG)neurons injured by glutamate(Glu)in vitro.Methods:DRG neurons of Wistar rat embryos were cultured in vitro for 48 h and then exposed to Glu(200 μmol/L)with or without Gin(50 μmol/L).The living cells were observed with an inverted contrast microscope.The cultures were processed for detecting the apoptosis rate by using flow cytometry.The fluorescent intensity of intracellular Ca2+ was detected by confocal laser scanning microscope(CLSM).Results:The living status of DRG cells with Gin incubation was better than that of incubated cultures without Gin.The shape of neuronal cell bodies or neurite networks were almost the same in the glutamic acid group with Gin compared with that of the normal control group.The apoptosis rate of cells incubated with Glu for 24 h was 41.1% in DRG cultures.The apoptosis rate of cells incubated with Glu and 50 μmol/L of Gin for 24 h was 7.6% in DRG cultures.The fluorescent intensity was lower in Gin with Glu group than that in Glu group(P＜0.01).The fluorescent intensity was lower in the control group than that in Glu group(P＜0.01).There was no significant difference in the fluorescent intensity between Gin with Glu group and control group(P＞0.05).Conclusion:Ginkgolides may reduce intracellular Ca2+ concentration,and then protect DRG neurons from neurotoxicity induced by Glu.

Effect of Baicalin on the Content of Major Amino Acid Transmitters in the Brain of Rat with Experimental Intracerebral Hemorrhage / 中国中医药信息杂志

Objective To study the effect of baicalin on the content of glutamate acid (Glu), aspartic acid (Asp), ?-aminobutyric acid (GABA) in the brain of rat with experimental intracerebral hemorrhage. Methods The intracerebral hemorrhage rat model was induced by collagen enzyme + heparin sodium. The rats were randomly divided into sham group, model group and high, middle, low dose group of baicalin. Rats were treated with the physiological saline and different concentration of baicalin respectively. The brain of each group was taken out three days later and the brain homogenate was prepared. The content of Glu, Asp and GABA was measured with the high performance liquid chromatography (HPLC). Results Compared with the sham group, the levels of Asp were obviously higher (P0.05) in each dose group of baicalin. Compared with the sham group, the contents of Glu were increased obviously (P

The protective effect of LY367385 on impairment of cultured mouse cerebral cortical neurons induced by sodium glutamate or oxygen-glucose deprivation / 中国康复理论与实践

@#ObjectiveTo investigate the protective effect of LY367385 on impairment of cultured mouse cerebral cortical neurons induced by sodium glutamate (Glu) or oxygen-glucose deprivation (OGD).MethodsNeuron damage induced by Glu or OGD, as well as the action of (S)-(+)-a-amino-4-carboxy-2-methylbenzeneacetic acid (LY367385) were measured by determining the leakage of lactate dehydrogenase (LDH) from neurons. Immunocytochemistry and immunofluorescent methods were used to detect the expression of anti-mGluR1α. Morphological observation of primary cortical neurons was performed by phase contrast microscope.ResultsFollowing the exposure to 0.1 mmol/L Glu for 1 h or OGD for 1 h, LDH leakage from neurons obviously increased (P< 0.01 ). 50 mmol/L LY367385, when co-incubated with Glu or OGD, markedly reduced the LDH leakage (P<0.01). The 24-h leakage of LDH was increased from cells exposed to 0.1 mmol/L Glu for 15 min. Pre-and post-treatment with LY367385 (50 mmol/L ) decreased the leakage of LDH. The cultured neurons expressed mGluR1α.ConclusionLY367385 has protective effect on neurons damaged by Glu or OGD. It may be related to antagonizing mGluR1α.