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1.
Molecules ; 25(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32110943

RESUMO

The green alga Klebsormidium flaccidum var. zivo is a rich source of proteins, polyphenols, and bioactive small-molecule compounds. An approach involving chromatographic fractionation, anti-inflammatory activity testing, ultrahigh performance liquid chromatography-mass spectrometry profiling, chemometric analysis, and subsequent MS-oriented isolation was employed to rapidly identify its small-molecule anti-inflammatory compounds including hydroxylated fatty acids, chlorophyll-derived pheophorbides, carotenoids, and glycoglycerolipids. Pheophorbide a, which decreased intracellular nitric oxide production by inhibiting inducible nitric oxide synthase, was the most potent compound identified with an IC50 value of 0.24 µM in lipopolysaccharides-induced macrophages. It also inhibited nuclear factor kappaB activation with an IC50 value of 32.1 µM in phorbol 12-myristate 13-acetate-induced chondrocytes. Compared to conventional bioassay-guided fractionation, this approach is more efficient for rapid identification of multiple chemical classes of bioactive compounds from a complex natural product mixture.


Assuntos
Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Clorófitas/química , Modelos Químicos , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Humanos , Camundongos , Células RAW 264.7 , Bibliotecas de Moléculas Pequenas/farmacologia
2.
Schizophr Res ; 103(1-3): 71-82, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18562176

RESUMO

Altered expression of structural and functional molecules expressed by astrocytes may play a role in the pathophysiology of schizophrenia. We investigated the hypothesis that the astrocytic enzyme glutamine synthetase, involved in maintaining the glutamate-glutamine cycle, and the cytoskeletal molecule glial fibrillary acidic protein (GFAP) are abnormally expressed in schizophrenia. We used Western blot analysis to measure levels of glutamine synthetase and GFAP in several brain regions of subjects with schizophrenia and a comparison group. We found that glutamine synthetase protein expression was significantly decreased in the superior temporal gyrus, and both glutamine synthetase and GFAP were significantly reduced in the anterior cingulate cortex in schizophrenia. Neither molecule demonstrated altered expression in the dorsolateral prefrontal cortex, primary visual cortex, or hippocampus. Chronic treatment with haloperidol did not alter the expression of these molecules in the rat brain, suggesting that our findings are not due to a medication effect. These data support an astrocytic component to the pathophysiology of schizophrenia and suggest that astrocytic molecules involved in enzymatic activity and cytoskeletal integrity may have a role in disease-related abnormalities in this illness.


Assuntos
Córtex Cerebral/patologia , Proteína Glial Fibrilar Ácida/análise , Glutamato-Amônia Ligase/análise , Esquizofrenia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Astrócitos/patologia , Western Blotting , Feminino , Giro do Cíngulo/patologia , Hipocampo/patologia , Humanos , Masculino , Córtex Pré-Frontal/patologia , Ratos , Valores de Referência , Lobo Temporal/patologia , Córtex Visual/patologia
3.
Toxicol Rep ; 5: 959-969, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30294555

RESUMO

Consumers are demanding plant-based alternative protein sources to complement traditional animal-based protein sources to fulfill their dietary protein requirements. KALGAE™, a dried algal biomass derived from Klebsormidium flaccidum var. ZIVO, is a potential source of plant-based protein that has been evaluated for safety to support its use as a food ingredient. There were no treatment-related adverse effects observed in the 14-day palatability/toxicity or 90-day dietary toxicity study in CRL Sprague-Dawley CD® IGS rats. In the 90-day study, KALGAE™ was administered to rats in the diet at 0, 37,500, 75,000, or 150,000 ppm. No adverse effects were attributed to the test substance for the following parameters: body weight, body weight gain, mean food consumption and efficiency, hematology, clinical chemistry, urinalysis, gross pathology, histopathology, or organ weights. Although some statistically significant effects were recorded, the effects were not considered to be of toxicological relevance. A No Observable Adverse Effect Level (NOAEL) of 150,000 ppm, equivalent to dietary intakes of 7895.2 (male) and 9708.09 (female) mg KALGAE™/kg body weight/day in rats was established. KALGAE™ was non-mutagenic in the in vitro bacterial reverse mutation assay at concentrations up to 5000 µg/plate (with or without S9 metabolic activation), nor was KALGAE™ genotoxic in the in vivo mammalian erythrocyte micronucleus test in Swiss albino (ICR) mice. These results support the safe use of KALGAE™ as an ingredient in foods.

4.
Neuroreport ; 17(11): 1181-5, 2006 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-16837850

RESUMO

Evidence of glutamatergic dysfunction in schizophrenia associated with the N-methyl-D-aspartate receptor has historically demonstrated changes primarily attributable to neurons. We propose an astrocytic component to N-methyl-D-aspartate receptor dysfunction in this illness. We studied the expression of serine racemase, an astrocytic enzyme which synthesizes the N-methyl-D-aspartate receptor coagonist D-serine, using Western blot analysis in postmortem hippocampus and cortex in schizophrenia and a comparison group. We found increased expression in the hippocampus in schizophrenia. This is the first study to demonstrate alterations in schizophrenia of an astrocytic enzyme responsible for synthesizing a neuromodulator, and further evidence that astrocytes may play a direct role in N-methyl-D-aspartate receptor dysfunction in schizophrenia.


Assuntos
Córtex Cerebral/enzimologia , Hipocampo/enzimologia , Racemases e Epimerases/metabolismo , Esquizofrenia/enzimologia , Idoso , Idoso de 80 Anos ou mais , Autopsia , Causas de Morte , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores de N-Metil-D-Aspartato/fisiologia
5.
Brain Res ; 1121(1): 83-94, 2006 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-17055465

RESUMO

Early in life, there is a delicate and critical balance aimed to maintain low hormone responses derived from the stress responsive hypothalamic-pituitary-adrenal axis (HPA). However, in the infant rat hypothalamic corticotrophin-releasing hormone (CRH) stress responses to environmental events are clearly seen even though other elements of the HPA axis may have limited responses. In view of the role of CRH in mediating behavior associated with stress and anxiety, we considered the ontogeny and the effects of prolonged maternal deprivation (DEP) in brain areas that express CRH-related molecules outside the hypothalamus. We hypothesized that DEP would alter the ontogeny of CRH, CRH binding protein and CRH receptor 1 in prefrontal cortex, amygdala, septum and hippocampus, areas that are part of the CRH extra hypothalamic system, and that a differential modulation would be observed in response to restraint. We compared non-deprived animals to animals subjected to 24 h of DEP at 6, 12 and 18 days of life. We found (1) developmental patterns, which were idiosyncratic to the anatomical area examined, and (2) a temporal response of mRNA levels which was also site specific. The genomic changes are not always related to maternal deprivation status, in fact DEP enhanced, suppressed or had no consequence on the underlying ontogenic progression and restraint response of these CRH-related molecules. We conclude that the extra hypothalamic CRH system is a dynamic system responding to developmental and environmental demands challenging the basic assumption of stress hypo responsiveness in the infant rat. This modulation may have important repercussions on morphological organization and events leading to neuroprotection.


Assuntos
Encéfalo/fisiologia , Hormônio Liberador da Corticotropina/genética , Privação Materna , Receptores de Hormônio Liberador da Corticotropina/genética , Envelhecimento , Tonsila do Cerebelo/crescimento & desenvolvimento , Tonsila do Cerebelo/fisiologia , Animais , Encéfalo/crescimento & desenvolvimento , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/fisiologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Hipocampo/crescimento & desenvolvimento , Hipocampo/fisiologia , Hibridização In Situ , Masculino , Modelos Animais , RNA Mensageiro , Ratos , Ratos Long-Evans , Ratos Sprague-Dawley , Estresse Psicológico
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