RESUMO
AIM: To determine the optimum condition for preparing chitooligosaccharide-catechin conjugate (COS-CAT) liposomes using different stabilising agents. METHODS: COS-CAT liposomes (0.1-1%, w/v) were prepared using soy phosphatidylcholine (SPC) (50-200 mM) and glycerol or cholesterol (25-100 mg). Encapsulation efficiency (EE), loading capacity (LC), physicochemical characteristics, FTIR spectra, thermal stability, and structure of COS-CAT liposomes were assessed. RESULTS: COS-CAT loaded liposome stabilised by cholesterol (COS-CAT-CHO) showed higher stability as shown by the highest EE (76.81%) and LC (4.57%) and the lowest zeta potential (ZP) (-76.51 mV), polydispersity index (PDI) (0.2674) and releasing efficiency (RE) (53.54%) (p < 0.05). COS-CAT-CHO showed the highest retention and relative remaining bioactivities of COS-CAT under various conditions (p < 0.05). FTIR spectra revealed the interaction between the choline group of SPC and -OH groups of COS-CAT. Phase transition temperature of COS-CAT-CHO was shifted to 184 °C, which was higher than others (p < 0.05). CONCLUSION: SPC and cholesterol-based liposome could be used as a promising vesicle for maintaining bioactivities of COS-CAT.
Assuntos
Catequina , Excipientes , Lipossomos , Quitina , LecitinasRESUMO
The quality of surimi gel can be improved using protein cross-linkers, especially from plant extracts. Apart from the presence of phenolic compounds, Duea ching fruit is rich in calcium, which can activate indigenous transglutaminase or form the salt bridge between protein chains. Its extract can serve as a potential additive for surimi. The effect of different media for the extraction of Duea ching was studied and the use of the extract in sardine surimi gel was also investigated. The Duea ching fruit extract (DCE) was prepared using distilled water and ethanol (EtOH) at varying concentrations. The DCE prepared using 60% EtOH (DCE-60) had the highest antioxidant activity and total phenolic content. When DCE-60 (0-0.125%; w/w) was added to the sardine surimi gel, the breaking force (BF), deformation (DF) and water holding capacity (WHC) of the gel upsurged and the highest values were attained with the 0.05% DCE-60 addition (p < 0.05). However, the whiteness of the gel decreased when DCE-60 levels were augmented. The gel containing 0.05% DCE-60, namely D60-0.05, showed a denser network and had a higher overall likeness score than the control. When the D60-0.05 gel was packed in air, under vacuum or modified atmospheric packaging and stored at 4 °C, BF, DF, WHC and whiteness gradually decreased throughout 12 days of storage. However, the D60-0.05 gel sample showed lower deterioration than the control, regardless of the packaging. Moreover, the gel packaged under vacuum conditions showed the lowest reduction in properties throughout the storage than those packaged with another two conditions. Thus, the incorporation of 0.05% DCE-60 could improve the properties of sardine surimi gel and the deterioration of the resulting gel was retarded when stored at 4 °C under vacuum packaging conditions.
RESUMO
Protein is a crucial nutritional ingredient in the daily human diet. Polyphenols (PPNs) are the abundant phytochemicals in plants, which are associated with health promotion as well as affect functionality in food systems. Both ingredients possess different types of functionalities (crosslinking, gelling, emulsifying, film-forming, etc.) and bioactivities (antioxidant, antimicrobial, anti-inflammatory, etc.). In the past decade, various methods have been implemented to enhance the functionalities and bioactivities of foods. Conjugation or grafting methods has been introduced widely. Conjugations of PPNs with proteins through various methods have been performed for the synthesis of the protein-polyphenol conjugate. Those potential grafting methods are alkaline associated, free-radical mediated, enzyme catalyzed, and chemical coupling methods. Several factors such as reaction conditions, type of proteins, and PPNs also influenced the conjugation efficiency. Various technologies, e.g., mass spectroscopy, fluorescence spectroscopy, UV spectroscopy, Fourier transform infrared spectroscopy, circular dichroism, and sodium dodecyl sulfate polyacrylamide gel electrophoresis have been used to elucidate conjugation and structural alternation of proteins and some properties of resulting conjugates. The prepared protein-PPN conjugates have been documented to enhance the bioactivities and functional properties of an initial protein. Moreover, conjugates have been employed in emulsions or as nanoparticles for nutraceutical delivery. Edible-films for food packaging and hydrogels for controlled drug release have been developed using protein-PPN conjugates. This chapter focuses on the methodologies and characteristics of protein-PPN conjugates and their applications in various food systems and nutraceutical field.
Assuntos
Antioxidantes , Polifenóis , Suplementos Nutricionais , Emulsões , Humanos , Plantas , Polifenóis/farmacologiaRESUMO
This study was undertaken to investigate the potential of bioscouring in the processing of undegummed sisal fibers, using xylano-pectinolytic enzymes. Optimum bioscouring was obtained at pH 8.5 and 50 mM buffer molarity, using xylanase (10 IU) and pectinase (8 IU), with a material to liquor proportion of 1:25 (g:ml), EDTA (2 mM) and Tween 80 (0.5%), at 50 °C temperature with agitation rate of 55 rpm and treatment period of 60 min. Enzymatic treatment of sisal fibers enhanced the brightness and whiteness by 11.52 and 6.83%, respectively, and reduced the yellowness by 7.14% in comparison to control. The use of xylanase and pectinase enzymes completely replaced the chemical scouring method for removing non-cellulosic impurities. Thus, enzymatic scouring is energy saving and ecofriendly, since it completely eliminated the use of toxic chemicals used in alkaline scouring. An increase of 23.75% and 11.58% in brightness and whiteness of enzymatically scoured cum bleached fibers, as compared to chemically scoured cum bleached fibers was finally obtained, along with reduction in yellowness by 27.99%. This is the first report demonstrating environmentally sustainable enzymatic approach for scouring of undegummed sisal fibers, using enzymes, simultaneously produced from a bacterial isolate.
Assuntos
Bacillus pumilus/enzimologia , Proteínas de Bactérias/química , Endo-1,4-beta-Xilanases/química , Pectinas/química , Poligalacturonase/química , Concentração de Íons de HidrogênioRESUMO
This study was carried out to demonstrate the biotechnological potential of xylano-pectinolytic enzymes on scouring of ramie fibers. Optimization of bioscouring process showed a maximum effect of enzymes with 50-mM strength of buffer, pH 8.5, fibers to liquid ratio of 1 : 20 (g:ml). Xylanase and pectinase dosage of 7.5 and 3.0 IU, respectively, was found to be best for removal of xylan and pectin impurities, after treatment time of 1.5 h, at 50 °C temperature and 55 rpm agitation rate. EDTA and Tween 80 at concentration of 1.5 mM and 1.25 %, respectively, were found to be the best for effective removal of impurities, in order to improve hydrophilicity of the fibers. After bioscouring, brightness and whiteness values of bioscoured fibers were increased by 9.72 and 7.10% in comparison with control fibers. After enzymatic scouring, a reduction of 14.45 % in yellowness was also seen in ramie fibers. Enzymatic treatment resulted in 6.97% increased brightness, 10.64% increased whiteness, and 4.11% decreased yellowness as compared with scoured ramie fibers. The results indicated that scouring using xylanase and pectinase enzymes could be a substitute for chemical scouring technique. Enzymatic scouring is, therefore, environmentally sustainable and saves energy, also decreases the consumption of harmful chemicals used in alkaline scouring. This is the first report showing the effect of xylanase and pectinase enzymes, produced by a bacterial isolate, on physico-chemical and various optical properties of ramie fibers.
Assuntos
Modelos Químicos , Têxteis , Boehmeria , Pectinas , Poligalacturonase , TemperaturaRESUMO
The genus Moringa Adans. comprises 13 species, of which Moringa oleifera Lam. native to India and cultivated across the world owing to its drought and frost resistance habit is widely used in traditional phytomedicine and as rich source of essential nutrients. Wide spectrum of phytochemical ingredients among leaf, flower, fruit, seed, seed oil, bark, and root depend on cultivar, season, and locality. The scientific studies provide insights on the use of M. oleifera with different aqueous, hydroalcoholic, alcoholic, and other organic solvent preparations of different parts for therapeutic activities, that is, antibiocidal, antitumor, antioxidant, anti-inflammatory, cardio-protective, hepato-protective, neuro-protective, tissue-protective, and other biological activities with a high degree of safety. A wide variety of alkaloid and sterol, polyphenols and phenolic acids, fatty acids, flavanoids and flavanol glycosides, glucosinolate and isothiocyanate, terpene, anthocyanins etc. are believed to be responsible for the pragmatic effects. Seeds are used with a view of low-cost biosorbent and coagulant agent for the removal of metals and microbial contamination from waste water. Thus, the present review explores the use of M. oleifera across disciplines for its prominent bioactive ingredients, nutraceutical, therapeutic uses and deals with agricultural, veterinarian, biosorbent, coagulation, biodiesel, and other industrial properties of this "Miracle Tree."
Assuntos
Moringa oleifera/química , Valor Nutritivo , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Suplementos Nutricionais , Flores/química , Frutas/química , Humanos , Índia , Fenômenos Fisiológicos da Nutrição/efeitos dos fármacos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Fitoterapia/métodos , Extratos Vegetais/química , Folhas de Planta/química , Sementes/químicaRESUMO
Recent studies report that loss and dysfunction of mitochondria and peroxisomes contribute to the myelin and axonal damage in multiple sclerosis (MS). In this study, we investigated the efficacy of a combination of lovastatin and AMP-activated protein kinase (AMPK) activator (AICAR) on the loss and dysfunction of mitochondria and peroxisomes and myelin and axonal damage in spinal cords, relative to the clinical disease symptoms, using a mouse model of experimental autoimmune encephalomyelitis (EAE, a model for MS). We observed that lovastatin and AICAR treatments individually provided partial protection of mitochondria/peroxisomes and myelin/axons, and therefore partial attenuation of clinical disease in EAE mice. However, treatment of EAE mice with the lovastatin and AICAR combination provided greater protection of mitochondria/peroxisomes and myelin/axons, and greater improvement in clinical disease compared with individual drug treatments. In spinal cords of EAE mice, lovastatin-mediated inhibition of RhoA and AICAR-mediated activation of AMPK cooperatively enhanced the expression of the transcription factors and regulators (e.g. PPARα/ß, SIRT-1, NRF-1, and TFAM) required for biogenesis and the functions of mitochondria (e.g. OXPHOS, MnSOD) and peroxisomes (e.g. PMP70 and catalase). In summary, these studies document that oral medication with a combination of lovastatin and AICAR, which are individually known to have immunomodulatory effects, provides potent protection and repair of inflammation-induced loss and dysfunction of mitochondria and peroxisomes as well as myelin and axonal abnormalities in EAE. As statins are known to provide protection in progressive MS (Phase II study), these studies support that supplementation statin treatment with an AMPK activator may provide greater efficacy against MS.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Lovastatina/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Peroxissomos/efeitos dos fármacos , Peroxissomos/metabolismo , Trifosfato de Adenosina/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Biomarcadores , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Feminino , Expressão Gênica , Humanos , Camundongos , Mitocôndrias/genética , Mitocôndrias/ultraestrutura , Peroxissomos/genética , Peroxissomos/ultraestrutura , Ribonucleotídeos/farmacologia , Medula Espinal/imunologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismoRESUMO
The genus Eucalyptus L'Heritier comprises about 900 species, of which more than 300 species contain volatile essential oil in their leaves. About 20 species, within these, have a high content of 1,8-cineole (more than 70%), commercially used for the production of essential oils in the pharmaceutical and cosmetic industries. However, Eucalyptus is extensively planted for pulp, plywood and solid wood production, but its leaf aromatic oil has astounding widespread biological activities, including antimicrobial, antiseptic, antioxidant, chemotherapeutic, respiratory and gastrointestinal disorder treatment, wound healing, and insecticidal/insect repellent, herbicidal, acaricidal, nematicidal, and perfumes, soap making and grease remover. In the present review, we have made an attempt to congregate the biological ingredients of leaf essential oil, leaf oil as a natural medicine, and pharmacological and toxicological values of the leaf oil of different Eucalyptus species worldwide. © 2017 Society of Chemical Industry.
Assuntos
Eucalyptus/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Animais , Humanos , Óleos Voláteis/toxicidade , Extratos Vegetais/toxicidade , Folhas de Planta/químicaRESUMO
Simultaneous production of xylanase and pectinase by Bacillus pumilus AJK under submerged fermentation was investigated in this study. Under optimized conditions, it produced 315 ± 16 IU/mL acidic xylanase, 290 ± 20 IU/mL alkaline xylanase, and 88 ± 9 IU/mL pectinase. The production of xylano-pectinolytic enzymes was the highest after inoculating media (containing 2% each of wheat bran and Citrus limetta peel, 0.5% peptone, 10 mM MgSO4, pH 7.0) with 2% of 21-hr-old culture and incubated at 37°C for 60 hr at 200 rpm. Xylanase retained 100% activity from pH 6.0 to10.0 after 3 hr of incubation, while pectinase showed 100% stability from pH 6.0 to 9.0 even after 6 hr of incubation. Cost-effective and concurrent production of xylanase and pectinase by a bacterial isolate in the same production media suggests its potential for various biotechnological applications. This is the first report of simultaneous production of industrially important extracellular xylano-pectinolytic enzymes by B. pumilus.
Assuntos
Análise Custo-Benefício , Endo-1,4-beta-Xilanases/biossíntese , Pectinas/metabolismo , Poligalacturonase/biossíntese , Xilanos/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática , Fermentação , Concentração de Íons de Hidrogênio , Poligalacturonase/metabolismo , Especificidade por Substrato , TemperaturaRESUMO
Low vitamin D level is a risk factor for various late-onset CNS demyelinating disorders. We investigated whether vitamin D deficiency influences disease in twitcher mice (GALC(twi/twi) ; twi), a murine model of Krabbe disease (KD), an inherited disorder caused by galactocerebrosidase (GALC) deficiency that leads to psychosine accumulation, oligodendrocyte (OL) loss, and CNS demyelination. We found that the in situ 1,25-dihydroxyvitamin D3 level was reduced, with a parallel increase in the expression of inflammatory cytokines and vitamin D-catabolizing enzymes in the brains of KD and twi mice compared with age-matched controls. Pups maintained on milk from lactating heterozygous (GALC(twi/+) ) mothers that were fed a vitamin D3-supplemented diet until weaning and then fed a vitamin D3-supplemented diet demonstrated delayed body weight loss and development of disease in twi mice. This delayed the onset of tremors and locomotor disabilities that eventually impacted the life span of twi mice (50 ± 2 days). Accordingly, the expression of antioxidant enzymes was increased with delayed psychosine accumulation, lipid peroxidation, and inflammatory response that eventually protected CNS myelin and axonal integrity in twi mice. In vitro studies revealed that 1,25-dihydroxyvitamin D3 enhances antioxidant defenses in OLs deficient for GALC or incubated with psychosine. Together these data provide the first evidence that vitamin D deficiency affects disease development in twi mice and that vitamin D3 supplementation has the potential to improve the efficacy of KD therapeutics.
Assuntos
Encéfalo/metabolismo , Calcitriol/metabolismo , Colecalciferol/uso terapêutico , Leucodistrofia de Células Globoides/dietoterapia , Leucodistrofia de Células Globoides/metabolismo , Leucodistrofia de Células Globoides/patologia , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Encéfalo/patologia , Calcitriol/administração & dosagem , Células Cultivadas , Colecalciferol/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Galactosilceramidase/deficiência , Glutationa/metabolismo , Humanos , Leucodistrofia de Células Globoides/genética , Camundongos , Camundongos Mutantes , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/metabolismo , Neuroglia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Vitamina D3 24-Hidroxilase/genética , Vitamina D3 24-Hidroxilase/metabolismoRESUMO
We have previously reported neuroprotection in spinal cord injury (SCI) by Lipitor [atorvastatin (AT)]-pre-treatment. Though informative, pre-treatment studies find only limited clinical application as trauma occurrence is unpredictable. Therefore, this study investigates the efficacy of AT treatment post-SCI. In a rat model of contusion-SCI resulting in complete hindlimb paralysis, AT treatment (5 mg/kg; gavage) was begun 2, 4, or 6 h post-SCI followed by a once daily dose thereafter for 6 weeks. While the placebo vehicle (VHC)-SCI rats showed substantial functional deficit, AT-SCI animals exhibited significant functional recovery. AT diminished injury-induced blood-spinal cord barrier (BSCB) dysfunction with significantly reduced infiltration and tumor necrosis factor-alpha/interleukin-1beta/inducible nitric oxide synthase expression at site of injury. BSCB protection in AT-SCI was attributable to attenuated matrix metalloproteinase-9 (MMP9) expression - a central player in BSCB disruption. Furthermore, endothelial MMP9 expression was found to be RhoA/ROCK pathway-mediated and regulated by AT through an isoprenoid-dependent mechanism. Attenuation of these early inflammatory events reduced secondary damage. Significant reduction in axonal degeneration, myelin degradation, gliosis, and neuronal apoptosis with resultant enhancement in tissue sparing was observed in AT-SCI compared with VHC-SCI. In summary, this novel report presenting the efficacy of post-injury AT treatment might be of critical therapeutic value as effective treatments are currently unavailable for SCI.
Assuntos
Células Endoteliais/efeitos dos fármacos , Ácidos Heptanoicos/farmacologia , Fármacos Neuroprotetores/farmacologia , Pirróis/farmacologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Medula Espinal/efeitos dos fármacos , Animais , Atorvastatina , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/fisiopatologia , Quimiotaxia de Leucócito/efeitos dos fármacos , Quimiotaxia de Leucócito/fisiologia , Citocinas/antagonistas & inibidores , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Células Endoteliais/metabolismo , Feminino , Transtornos Neurológicos da Marcha/tratamento farmacológico , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Ácidos Heptanoicos/uso terapêutico , Metaloproteinase 9 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz , Fármacos Neuroprotetores/uso terapêutico , Paralisia/tratamento farmacológico , Paralisia/etiologia , Paralisia/fisiopatologia , Pirróis/uso terapêutico , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Medula Espinal/irrigação sanguínea , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Terpenos/metabolismo , Resultado do Tratamento , Proteína rhoA de Ligação ao GTP/efeitos dos fármacos , Proteína rhoA de Ligação ao GTP/metabolismoRESUMO
Combination therapy with multiple sclerosis (MS) therapeutics is gaining momentum over monotherapy for improving MS. Lovastatin, an HMG-CoA reductase inhibitor (statin), was immunomodulatory in an experimental autoimmune encephalomyelitis (EAE) model of MS. Lovastatin biases the immune response from Th1 to a protective Th2 response in EAE by a different mechanism than 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside, an immunomodulating agent that activates AMP-activated protein kinase. Here we tested these agents in combination in an EAE model of MS. Suboptimal doses of these drugs in combination were additive in efficacy against the induction of EAE; clinical symptoms were delayed and severity and duration of disease was reduced. In the central nervous system, the cellular infiltration and proinflammatory immune response was decreased while the anti-inflammatory immune response was increased. Combination treatment biased the class of elicited myelin basic protein antibodies from IgG2a to IgG1 and IgG2b, suggesting a shift from Th1 to Th2 response. In addition, combination therapy lessened inflammation-associated neurodegeneration in the central nervous system of EAE animals. These effects were absent in EAE animals treated with either drug alone at the same dose. Thus, our data suggest that agents with different mechanisms of action such as lovastatin and 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside, when used in combination, could improve therapy for central nervous system demyelinating diseases and provide a rationale for testing them in MS patients.
Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Encefalomielite Autoimune Experimental/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Hipoglicemiantes/administração & dosagem , Fatores Imunológicos/administração & dosagem , Lovastatina/administração & dosagem , Esclerose Múltipla/tratamento farmacológico , Ribonucleotídeos/administração & dosagem , Proteínas Quinases Ativadas por AMP , Aminoimidazol Carboxamida/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Complexos Multienzimáticos/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Proteína Básica da Mielina/imunologia , Proteínas Serina-Treonina Quinases/imunologia , Ratos , Ratos Endogâmicos Lew , Células Th1/imunologia , Células Th1/patologia , Células Th2/imunologia , Células Th2/patologiaRESUMO
Peroxisomes are ubiquitous subcellular organelles and abnormality in their biogenesis and specific gene defects leads to fatal demyelinating disorders. We report that neuroinflammatory disease in brain of experimental autoimmune encephalomyelitis (EAE) rats decreased the peroxisomal functions. Degradation of very long chain fatty acids decreased by 47% and resulted in its accumulation (C26:0, 40%). Decreased activity (66% of control) of dihydroxyacetonephosphate acyltransferase (DHAP-AT), first enzyme in plasmalogens biosynthesis, resulted in decreased levels of plasmalogens (16-30%). Catalase activity, a peroxisomal enzyme, was also reduced (37%). Gene microarray analysis of EAE spinal cord showed significant decrease in transcripts encoding peroxisomal proteins including catalase (folds 3.2; p<0.001) and DHAP-AT (folds 2.6; p<0.001). These changes were confirmed by quantitative reverse transcription polymerase chain reaction (RT-PCR) analysis, suggesting that decrease of peroxisomal functions in the central nervous system will have negative consequences for myelin integrity and repair because these lipids are major constituents of myelin. However, lovastatin (a cholesterol lowering and anti-inflammatory drug) administered during EAE induction provided protection against loss/down-regulation of peroxisomal functions. Attenuation of induction of neuroinflammatory mediators by statins in cultured brain cells [J. Clin. Invest. 100 (1997) 2671-2679], and in central nervous system of EAE animals and thus the EAE disease [J. Neurosci. Res. 66 (2001) 155-162] and the studies described here indicate that inflammatory mediators have a marked negative effect on peroxisomal functions and thus on myelin assembly and that these effects can be prevented by treatment with statins. These observations are of importance because statins are presently being tested as therapeutic agents against a number of neuroinflammatory demyelinating diseases.
Assuntos
Anticolesterolemiantes/uso terapêutico , Sistema Nervoso Central/efeitos dos fármacos , Encefalomielite Autoimune Experimental/prevenção & controle , Lovastatina/uso terapêutico , Transtornos Peroxissômicos/prevenção & controle , Transportadores de Cassetes de Ligação de ATP/metabolismo , ATPases Associadas a Diversas Atividades Celulares , Acil-CoA Oxidase/genética , Acil-CoA Oxidase/metabolismo , Aciltransferases/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Catalase/metabolismo , Sistema Nervoso Central/metabolismo , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/complicações , Ácidos Graxos/metabolismo , Feminino , Adjuvante de Freund , Imuno-Histoquímica/métodos , Inflamação/etiologia , Inflamação/prevenção & controle , Proteínas de Membrana/metabolismo , Análise em Microsséries/métodos , Transtornos Peroxissômicos/etiologia , Peroxissomos/efeitos dos fármacos , Peroxissomos/fisiologia , RNA Mensageiro/biossíntese , Ratos , Ratos Endogâmicos Lew , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodosRESUMO
In the present study a possible role of glycosphingolipids (GSLs) in inducible nitric oxide synthase (iNOS) gene expression and nitric oxide (NO) production after spinal cord injury (SCI) in rats has been established. In primary rat astrocytes lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma) treatment increased the intracellular levels of lactosylceramide (LacCer) and induced iNOS gene expression. d-Threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol.HCI (PDMP), a glucosylceramide synthase and LacCer synthase (galactosyltransferase, GalT-2) inhibitor, inhibited LPS/IFN-gamma induced iNOS expression, which was reversed by exogenously supplied LacCer, but not by other glycosphingolipids. LPS/IFN-gamma caused a rapid increase in the activity of GalT-2 and synthesis of LacCer. Silencing of GalT-2 gene with the use of antisense oligonucleotides resulted in decreased LPS/IFN-gamma-induced iNOS, TNF-alpha, and IL-1beta gene expression. The PDMP-mediated reduction in LacCer production and inhibition of iNOS expression correlated with decreased Ras and ERK1/2 activation along with decreased IkappaB phosphorylation, NF-kappaB DNA binding activity, and NF-kappaB-luciferase reporter activity. LacCer-mediated Ras activation was redox-mediated and was attenuated by antioxidants N-acetyl cysteine (NAC) and pyrrolidine dithiocarbamate (PDTC). In vivo administration of PDMP after SCI resulted in improved functional outcome (Basso, Beattie, Bresnahan score); inhibition of iNOS, TNF-alpha, and IL-1beta expression; decreased neuronal apoptosis; and decreased tissue necrosis and demyelination. The in vivo studies supported the conclusions drawn from cell culture studies and provided evidence for the possible role of GalT-2 and LacCer in SCI-induced inflammation and pathology. To our knowledge this is the first report of a role of LacCer in iNOS expression and the advantage of GSL depletion in attenuating post-SCI inflammation to improve the outcome of SCI.