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1.
Biochem Pharmacol ; 138: 96-106, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28461124

RESUMO

The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) controls the expression of genes involved in the regulation of lipid and glucose metabolism, cell proliferation/differentiation as well as inflammatory pathways. Pivotal studies in human sebocytes and isolated sebaceous glands have raised the interesting possibility that compounds acting on PPARγ can modulate sebaceous lipids and inflammation and, as such, may be useful in the treatment of acne. To investigate the role of this receptor in the regulation of lipid synthesis, proliferation and inflammation, we used the SZ95 sebaceous gland cell line stimulated with insulin. In sebocytes, insulin signaling activated the phosphatidylinositide 3-kinase-Akt (PI3K/Akt) and mammalian target of rapamycin (mTOR) pathways, which, in turn, induced high protein/lipid synthesis, increased cell growth and proliferation as well as inflammation. As regards lipogenesis, insulin initially stimulated the formation of unsaturated lipids and then the neosynthesis of lipids. The results showed, that the modulation of PPARγ, counteracted the insulin-induced altered lipogenesis, evident through a decrease in gene expression of key enzymes responsible for the synthesis of fatty acids, and through a reduction of lipid species synthesis analyzed by Oil/Nile Red staining and GC-MS. PPARγ modulation also regulated the insulin-induced proliferation, inhibiting the cell cycle progression and p21WAF1/CIP1 (p21) protein reduction. Moreover, the expression of inflammatory cytokines, induced by insulin or lipopolysaccharide (LPS), was down-modulated. In PPARγ-deficient cells or in the presence of GW9662 antagonist, all these observed effects were abolished, indicating that PPARγ activation plays a role in regulating alteration of lipogenesis, cell proliferation and inflammatory signaling. We demonstrated that selective modulation of PPARγ activity is likely to represent a therapeutic strategy for the treatment of acne.


Assuntos
Regulação da Expressão Gênica , Lipogênese , PPAR gama/metabolismo , Glândulas Sebáceas/metabolismo , Sebo/metabolismo , Transdução de Sinais , Acetanilidas/efeitos adversos , Acetanilidas/farmacologia , Anilidas/efeitos adversos , Anilidas/farmacologia , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/agonistas , Citocinas/metabolismo , Fármacos Dermatológicos/efeitos adversos , Fármacos Dermatológicos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hipoglicemiantes/antagonistas & inibidores , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Antagonistas da Insulina/efeitos adversos , Antagonistas da Insulina/farmacologia , Lipogênese/efeitos dos fármacos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/toxicidade , PPAR gama/agonistas , PPAR gama/antagonistas & inibidores , PPAR gama/genética , Fenilpropionatos/efeitos adversos , Fenilpropionatos/farmacologia , Interferência de RNA , Glândulas Sebáceas/citologia , Glândulas Sebáceas/efeitos dos fármacos , Glândulas Sebáceas/imunologia , Sebo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
2.
Buenos Aires; GCBA. Gerencia Operativa de Epidemiología; 17 mar. 2017. a) f: 46 l:51 p. graf, tab, mapas.(Boletín Epidemiológico Semanal: Ciudad Autónoma de Buenos Aires, 2, 30).
Monografia em Espanhol | UNISALUD, BINACIS, InstitutionalDB, LILACS | ID: biblio-1104294

RESUMO

El plan de Prevención y Control de Enfermedades Transmitidas por Mosquito (ETM): Dengue, Fiebre Chikungunya, Amarilla, y Zika de la CABA establece cuatro escenarios teóricos de riesgo que orientan la implementación de las acciones de prevención y control. En el presente informe se presentan los estudios de foco investigados en nuestra Área Programática (AP) y su georreferencia, a fin de obtener un diagnóstico situacional local que permita la ejecución de intervenciones oportunas y eficaces a fin de limitar la aparición de nuevos casos en el contexto epidémico 2015-2016. El objetivo general fue estudiar la epidemia de ETM para su comprensión y abordaje en el Área Programática del Hospital General de Agudos Juan A. Fernández, y el objetivo específico, prevenir y limitar la aparición de nuevos casos de ETM. (AU)


Assuntos
Humanos , Animais , Febre Amarela/prevenção & controle , Febre Amarela/epidemiologia , Área Programática de Saúde , Diagnóstico da Situação de Saúde , Dengue/prevenção & controle , Dengue/epidemiologia , Febre de Chikungunya/prevenção & controle , Febre de Chikungunya/epidemiologia , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/epidemiologia , Mosquitos Vetores/patogenicidade , Hospitais Municipais
3.
Br J Dermatol ; 171(6): 1326-35, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24975960

RESUMO

BACKGROUND: Leptin, the adipocyte-secreted hormone that regulates weight, is known to link lipid metabolism with inflammation in various cell types. However, its role in human sebocytes has not yet been investigated. OBJECTIVES: The purpose of this study was to investigate the effects of leptin in human sebaceous gland biology. METHODS: Expression of the long form of the leptin receptor (Ob-Rb) was detected by real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and immunochemistry. Lipid analysis was by high-performance thin-layer chromatography, gas chromatography-mass spectrometry and time-of-flight mass spectrometer mass detection. Lipid bodies were visualized by BODIPY staining using fluorescent microscopy and measured by flow cytometry. Interleukin (IL)-6 and IL-8 mRNA levels were assessed by real-time qRT-PCR and their release was evaluated by enzyme-linked immunosorbent assay. Cyclooxygenase (COX)-2 and 5-lipooxygenase (LOX) protein expression and phosphorylation of p65 and signal transducer and activator of transcription (STAT)-3 were determined by Western blot analysis. RESULTS: Expression of Ob-Rb was detected in human sebaceous glands and in cultured human SZ95 sebocytes. The treatment of SZ95 sebocytes with leptin led to enlarged intracellular lipid bodies, increased ratios of unsaturated/saturated fatty acids and decreased vitamin E levels. Further supporting a proinflammatory role, leptin induced COX-2 and 5-LOX expression in SZ95 sebocytes and augmented the production of IL-6 and IL-8 cytokines. On leptin treatment, the STAT-3 and nuclear factor-κB pathways were activated, indicating that these known leptin signalling pathways are active in human sebocytes. CONCLUSIONS: Our findings suggest that leptin signalling may be involved in the proinflammatory regulation of sebaceous lipid metabolism and the induction of inflammatory enzymes and cytokines.


Assuntos
Leptina/fisiologia , Receptores para Leptina/metabolismo , Glândulas Sebáceas/metabolismo , Araquidonato 5-Lipoxigenase/metabolismo , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Metabolismo dos Lipídeos/fisiologia , Lipídeos/farmacologia , Lipogênese/fisiologia , NF-kappa B/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/fisiologia
4.
J Eur Acad Dermatol Venereol ; 28(12): 1792-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24628899

RESUMO

BACKGROUND: Sebum plays a key role in the initiation of the acne lesions. Oxidized sebum lipids cause keratynocytes hyperproliferation and inflammatory cytokines release. Association between sebum oxidation and comedogenesis has been little investigated in comedonal acne. OBJECTIVES: Evaluation of sebum oxidation parameters and levels of inflammatory cytokines (IL-1α) in patients with mild comedonal acne (MCA) before and after the treatment with a mixed RetinSphere® - vitamin E formulation. METHODS: Sebum excretion rate (SER), squalene concentration, and oxidation degree of sebum were measured in 18 MCA patients and 10 controls. IL-1α levels in the stratum corneum were measured in both lesional and non-lesional facial areas of MCA patients. Sebum parameters and IL-1α were measured at week 4 of topical treatment. Reflectance confocal microscopy (RCM) was performed in a subset of four patients at the baseline and at week 4 and all patients were assessed clinically before and following the 8 week-treatment. RESULTS: Sebum excretion rate and squalene concentration were comparable between MCA patients and healthy controls. Lipid peroxidation (LPO) and the percentage of oxidized squalene (SQOX) were significantly elevated in the sebum of MCA patients. The concentration of the proinflammatory cytokine IL-1α in stratum corneum was significantly higher in the lesional area compared with non-lesional area of the MCA patients at the baseline. At week 4, while SER and squalene concentration did not vary significantly, the LPO levels and the SQOX percentage resulted decreased at a significant extent. Following the treatment, IL-1α concentration in the lesional area reached values comparable to those of unaffected areas. Consistent with the biochemical data, RCM showed the reduction of hyperkeratinization and of inflammatory cells infiltration of the adnexal structures epithelium, significant clinical improvement was recorded at week 8. CONCLUSION: The data further support the involvement of lipid oxidation and particularly by-products of squalene oxidation in comedogenesis.


Assuntos
Acne Vulgar/metabolismo , Interleucina-1alfa/metabolismo , Sebo/metabolismo , Adolescente , Feminino , Humanos , Masculino , Microscopia Confocal , Oxirredução
5.
Lett Appl Microbiol ; 50(1): 65-70, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19929906

RESUMO

AIM: To evaluate the reliability of culture-independent methods in comparison with culture-dependent ones for the detection of Arcobacter spp. in estuarine waters of Southern Italy. METHODS AND RESULTS: PCR and fluorescent in situ hybridization (FISH) procedures were used to detect arcobacters directly in water samples and after enrichment cultures. The samples totally were positive by molecular methods (PCR and FISH) but only 75% were culture positive, confirming the limitation of these latter to detect Arcobacter spp. in natural samples. Culturable arcobacters were retrieved in all times except in July, and isolated species were ascribed only to Arcobacter cryaerophilus. CONCLUSIONS: Culturable and nonculturable forms of Arcobacter in the estuarine environment were present. PCR assays were more sensitive than traditional culture in detecting Arcobacter butzleri and A. cryaerophilus. FISH comparatively to PCR technique may provide information about cell morphology and viability of single cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Our investigation indicates the existence of an environmental reservoir of potential pathogenic arcobacters in an estuarine Italian area, which may survive under a viable but not culturable state.


Assuntos
Arcobacter/isolamento & purificação , Hibridização in Situ Fluorescente , Reação em Cadeia da Polimerase , Rios/microbiologia , Água do Mar/microbiologia , Arcobacter/genética , Arcobacter/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Meios de Cultura , DNA Bacteriano/análise , DNA Ribossômico/análise , Itália , RNA Bacteriano/genética , RNA Ribossômico 16S/genética
6.
Res Vet Sci ; 88(3): 379-84, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19963231

RESUMO

Bartonella henselae is considered an emerging pathogen of veterinary and medical interest that can be occasionally transmitted to humans. Cats are considered to be the only reservoir host for B. henselae. In this study, we used a nested-PCR assay to investigate the prevalence of B.henselae and Bartonella clarridgeiae DNA in peripheral blood samples, fine needle lymph node aspirate specimens and oral swabs from 85 cats in order to develop an easy diagnostic strategy for the selection of infection-free cats that are being considered as pets, especially for immunocompromised patients. Overall, molecular analysis showed that 71 cats (83.5%) tested PCR positive for the presence of B. henselae DNA. PCR amplification of DNA B. henselae produced positive products from lymph node aspirate specimens (62/85; 72.9%) similar to those obtained from blood samples (60/85; 70.6%) and higher than those from oral swabs (51/85; 60%) of cats. No PCR product was obtained for B. clarridgeiae. The simultaneous analysis of three different clinical samples in our study increased the diagnostic possibilities for B. henselae infection in the examined cats from 60-72.9% to 83.5%. Lymph node aspirates were found to be the most effective clinical samples for the detection of B. henselae and blood samples were the next best. Oral swab samples were used in this study with good results when considered in combination with blood and/or lymph node aspiration. The use of nested-PCR assay on these three clinical samples may enhance the diagnostic sensitivity for bartonellosis in cats irrespective of the clinical status of animals.


Assuntos
Infecções por Bartonella/veterinária , Bartonella henselae/isolamento & purificação , Bartonella/isolamento & purificação , Gatos/microbiologia , Animais , Animais Domésticos , Bartonella/genética , Infecções por Bartonella/sangue , Infecções por Bartonella/transmissão , Bartonella henselae/genética , DNA Bacteriano/sangue , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Feminino , Amplificação de Genes , Humanos , Itália , Linfonodos/microbiologia , Masculino , Boca/microbiologia , Reação em Cadeia da Polimerase , Sifonápteros , Infestações por Carrapato/diagnóstico , Infestações por Carrapato/veterinária
7.
J Appl Microbiol ; 106(5): 1661-6, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19226387

RESUMO

AIMS: To evaluate the presence of Arcobacter spp. in different biological samples from domestic cats in Southern Italy by using a species-specific PCR assay and thus to elucidate their potential significance as sources of human infection. METHODS AND RESULTS: We investigated the prevalence of Arcobacter DNA in oral swabs, in peripheral blood samples and fine needle lymph node aspirate specimens from 85 cats of which 17 were clinically healthy and 68 had clinical signs of oral disease or lymphadenomegaly. Overall, molecular analysis has shown that Arcobacter-specific DNA was found in 78.8% (67 of 85) of all the cats. In the 67 Arcobacter-positive cats, 66 (77.6%) and 29 (34.1%) were found positive for Arcobacter butzleri and Arcobacter cryaerophilus, respectively. None of the examined samples gave a PCR product for Arcobacter skirrowii. CONCLUSIONS: This study demonstrates that pet cats commonly carry Arcobacter in the oral cavity. According to the clinical data, the Arcobacter detection results showed no significant difference between cats with oral pathology and those suffering from other different pathologies. SIGNIFICANCE AND IMPACT OF THE STUDY: Pet cats harbour Arcobacter spp. and may play a role in their dissemination in the domestic habitat. The high prevalence in a limited number of cat samples in this study may be of significance.


Assuntos
Arcobacter/isolamento & purificação , Portador Sadio/microbiologia , Doenças do Gato/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Animais , Animais Domésticos , Arcobacter/genética , Bacteriemia/microbiologia , Portador Sadio/epidemiologia , Portador Sadio/transmissão , Doenças do Gato/epidemiologia , Doenças do Gato/transmissão , Gatos , DNA Bacteriano/química , Feminino , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/transmissão , Itália/epidemiologia , Linfonodos/microbiologia , Linfonodos/patologia , Masculino , Boca/microbiologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Análise de Sequência de DNA , Especificidade da Espécie
9.
Appl Environ Microbiol ; 74(10): 3266-8, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18378639

RESUMO

Two strains of Arcobacter butzleri, ATCC 49616 and an environmental isolate, became nonculturable in seawater microcosms at 4 degrees C by 20 days and at room temperature by 14 days. Nonculturable cells were viable for up to 270 days of incubation in microcosms. Resuscitation of A. butzleri cells from microcosms at both temperatures was achieved 9 days after nutrient addition.


Assuntos
Arcobacter/crescimento & desenvolvimento , Arcobacter/fisiologia , Água do Mar/microbiologia , Contagem de Colônia Microbiana , Hibridização in Situ Fluorescente , Viabilidade Microbiana , Microscopia de Fluorescência , Temperatura , Fatores de Tempo
10.
J Chemother ; 20(6): 661-71, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19129062

RESUMO

The incidence of invasive fungal infections (IFIs) caused by both common and uncommon opportunistic fungi is increasing along with emerging fungal resistance. Since traditional agents (amphotericin B, fluconazole, itraconazole) are limited by an inadequate spectrum of activity, drug resistance or toxicity, there is a great interest in the development of new antifungal agents for treatment of IFIs in high-risk populations. In recent years a number of systemic antifungal drugs have become available and options for treatment of IFIs have expanded. A new generation of triazole agents (voriconazole, posaconazole, isavuconazole, ravuconazole and albaconazole), with a broad spectrum of activity and sufficient improvements in potency to overcome resistance have emerged and represent an alternative to conventional antifungals for the prevention and treatment of IFIs. This article focuses on the microbiology, pharmacology, clinical efficacy and safety of the new antifungal triazole generation.


Assuntos
Antifúngicos/farmacologia , Micoses/tratamento farmacológico , Triazóis/farmacologia , Farmacorresistência Fúngica/fisiologia , Humanos
12.
Chem Phys Lipids ; 134(2): 161-71, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15784234

RESUMO

The reaction of (13S,9Z,11E)-13-hydroxy-9,11-octadecadienoic acid (1a), one of the major peroxidation products of linoleic acid and an important physiological mediator, with the Fenton reagent (Fe(2+)/EDTA/H(2)O(2)) was investigated. In phosphate buffer, pH 7.4, the reaction proceeded with >80% substrate consumption after 4h to give a defined pattern of products, the major of which were isolated as methyl esters and were subjected to complete spectral characterization. The less polar product was identified as (9Z,11E)-13-oxo-9,11-octadecadienoate (2) methyl ester (40% yield). Based on 2D NMR analysis the other two major products were formulated as (11E)-9,10-epoxy-13-hydroxy-11-octadecenoate (3) methyl ester (15% yield) and (10E)-9-hydroxy-13-oxo-10-octadecenoate (4) methyl ester (10% yield). Mechanistic experiments, including deuterium labeling, were consistent with a free radical oxidation pathway involving as the primary event H-atom abstraction at C-13, as inferred from loss of the original S configuration in the reaction products. Overall, these results provide the first insight into the products formed by oxidation of 1a with the Fenton reagent, and hint at novel formation pathways of the hydroxyepoxide 3 and hydroxyketone 4 of potential (patho)physiological relevance in settings of oxidative stress.


Assuntos
Ácidos Graxos Insaturados/química , Peróxido de Hidrogênio/química , Ferro/química , Ácidos Linoleicos/química , Radicais Livres/química , Peroxidação de Lipídeos , Modelos Químicos , Oxirredução
13.
J Appl Microbiol ; 98(3): 768-74, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15715881

RESUMO

AIMS: The occurrence of Helicobacter pylori in the coastal zone of the Straits of Messina (Italy) as free-living and associated with plankton was studied. METHODS AND RESULTS: Monthly sampling of seawater and plankton was carried out from April 2002 to March, 2003. All environmental samples analysed by cultural method, did not show the presence of H. pylori. The DNA extracted from all environmental samples was tested by PCR by using primers for H. pylori 16S rRNA, ureA and cagA. 16S rRNA PCR yielded amplified products of 522-bp in 15 of 36 (41.7%) of the environmental samples. By using the ureA primers to amplify the urea signal sequences, the predicted PCR products of 491-bp were obtained from eight (22.2%) of 36 environmental samples. PCR with cagA primers yielded amplified products of 349-bp in DNA extracted of seven of 36 (19.4%) of the environmental samples. When 16S rRNA, ureA and cagA amplified gene sequences were aligned with H. pylori 26695 and J99 genome sequences, we obtained a percentage of alignment over 90%. CONCLUSIONS: The detection of H. pylori genes in marine samples allows us to consider the marine environment a possible reservoir for this pathogenic bacterium. SIGNIFICANCE AND IMPACT OF THE STUDY: The direct detection of H. pylori genes may be relevant in order to consider the marine environment as significant reservoir for this bacterium.


Assuntos
Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , RNA Ribossômico 16S/análise , Água do Mar , Microbiologia da Água , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Sequência de Bases , Reservatórios de Doenças , Monitoramento Ambiental/métodos , Genoma Bacteriano , Humanos , Itália , Dados de Sequência Molecular , Plâncton , Reação em Cadeia da Polimerase/métodos , Alinhamento de Sequência
15.
Appl Environ Microbiol ; 70(3): 1271-6, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15006743

RESUMO

The occurrence of Arcobacter spp. was studied in seawater and plankton samples collected from the Straits of Messina, Italy, during an annual period of observation by using cultural and molecular techniques. A PCR assay with three pairs of primers targeting the 16S and 23S rRNA genes was used for detection and identification of Arcobacter butzleri, Arcobacter cryaerophilus, and Arcobacter skirrowii in cultures and environmental samples. Only one of the Arcobacter species, A. butzleri, was isolated from seawater and plankton samples. With some samples the A. butzleri PCR assay gave amplified products when cultures were negative. A. cryaerophilus and A. skirrowii were never detected by culture on selective agar plates; they were detected only by PCR performed directly with environmental samples. Collectively, our data suggest that culturable and nonculturable forms of Arcobacter are present in marine environments. The assay was useful for detecting Arcobacter spp. both as free forms and intimately associated with plankton. This is the first report showing both direct isolation of A. butzleri and the presence of nonculturable Arcobacter spp. in the coastal environment of the Mediterranean Sea.


Assuntos
Arcobacter/genética , Arcobacter/isolamento & purificação , Água do Mar/microbiologia , Animais , Sequência de Bases , Primers do DNA/genética , DNA Bacteriano/genética , DNA Ribossômico/genética , Genes Bacterianos , Itália , Mar Mediterrâneo , Plâncton/microbiologia , Reação em Cadeia da Polimerase , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética
16.
Int J Antimicrob Agents ; 21(5): 488-91, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12727085

RESUMO

Seventeen strains of Arcobacter butzleri and thirteen of Arcobacter cryaerophilus, were tested for their antimicrobial susceptibility to 26 antimicrobial agents. Among beta-lactams agents in this study, imipenem was the most active agent against both A. butzleri and A. cryaerophilus isolates with MIC(90) values of 2 and 4 mg/l, respectively. The most active cephalosporin tested was cefepime, although it was more active against A. butzleri (MIC(90) 8 mg/l) than A. cryaerophilus (MIC(90) 64 mg/l). Levofloxacin, marbofloxacin, enrofloxacin and ciprofloxacin were the best-performing fluoroquinolones against these species. Of the aminoglycosides, amikacin was the most active agent against both A. butzleri and A. cryaerophilus strains with MIC(90) values of 64 and 16 mg/l, respectively. All isolates showed high levels of resistance to penicillins, macrolides, chloramphenicol, trimethoprim and vancomycin.


Assuntos
Antibacterianos/farmacologia , Arcobacter/efeitos dos fármacos , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana
17.
Int J Immunopathol Pharmacol ; 16(1): 49-54, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12578731

RESUMO

Chemical irritants are able to produce several biological modifications of the skin, including the direct or indirect production of cytokines and reactive oxygen species leading to an inflammatory reaction. This report examines the existence of a possible correlation between the skin sensitivity to the irritant sodium dodecyl sulphate (SDS) and the activity of the enzymatic antioxidants. In twenty-three healthy subjects the evaluation of the epidermal and peripheral blood mononuclear cells (PBMCs) activities of Superoxide Dismutase (SOD) and Catalase (Cat) demonstrate a significant correlation (r= 0,85 and p< 0,005 for SOD, and r= 0,87 and p< 0,0001 for Cat). Based on this result, on a further group of normal subjects (n=13) we studied the link between the threshold dose of skin reactivity to SDS and the activities of the enzymatic antioxidants in PBMCs. The degree of skin modification induced by SDS, applied at different concentrations for 24 hrs, was determined by means of Trans Epidermal Water Loss (TEWL), Erythemal Index or by Visual Score (VS). The minimal dose of the irritant capable of inducing skin modifications, was significantly correlated with SOD (r=0,77) and Cat (r=0,81) activities in PBMCs, and the modification of TEWL or EI were inversely correlated with levels of antioxidants in PBMCs (r=-0,62 for SOD and r=-0,66 for Cat). Our results indicate that the skin reactivity to irritants can be modulated by the levels of antioxidants, and suggest a possible therapeutical approach in preventing irritant contact dermatitis.


Assuntos
Antioxidantes/metabolismo , Dermatite de Contato/enzimologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/enzimologia , Dodecilsulfato de Sódio/farmacologia , Adulto , Feminino , Humanos , Masculino , Testes Cutâneos/métodos
18.
J Invest Dermatol ; 117(4): 908-13, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11676831

RESUMO

Several hypotheses have been made about the pathogenesis of vitiligo, and some of them have considered a systemic involvement in the course of the disease. Evidence has been presented on the role of oxidative stress as the initial event in melanocyte degeneration. In accordance with this view, we determined the levels of some antioxidants, i.e., superoxide dismutase, catalase, reduced glutathione, and vitamin E, in erythrocytes and/or peripheral blood mononuclear cells from patients with active or stable vitiligo and from a control group of healthy subjects. In erythrocytes the parameters evaluated were not significantly different. On the contrary, in peripheral blood mononuclear cells, superoxide dismutase activity was increased in both groups of patients, whereas catalase activity, reduced glutathione and vitamin E levels were decreased exclusively in subjects with active disease. The imbalance of antioxidants was associated with hyperproduction of reactive oxygen species due to a mitochondrial impairment as cyclosporin A, an inhibitor of the permeability transition pores opening, significantly reduced the reactive oxygen species production. Moreover an alteration of the mitochondrial transmembrane potential and a higher percentage of apoptotic cells were observed in active vitiligo patients. Based on these results, we suggest that, in vitiligo, mitochondria might be the target of different stimuli, such as reactive oxygen species generation, cytokines production, catecholamine release, alteration of Ca2+ metabolism, all of which capable of inducing melanocyte degeneration.


Assuntos
Mitocôndrias/fisiologia , Monócitos/fisiologia , Vitiligo/fisiopatologia , Adulto , Apoptose , Feminino , Humanos , Masculino , Potenciais da Membrana , Pessoa de Meia-Idade , Oxirredutases/sangue , Espécies Reativas de Oxigênio/sangue , Vitiligo/sangue
19.
J Chromatogr B Biomed Sci Appl ; 757(1): 69-78, 2001 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-11419750

RESUMO

We developed a sensitive and specific liquid chromatography-electrospray mass spectrometric (HPLC-ESI-MS) assay for the simultaneous determination of reduced and oxidized glutathione (GSH and GSSG) in peripheral blood mononuclear cells (PBMC). Following derivatization with N-ethylmaleimide to prevent GSH auto-oxidation, addition of thiosalicylic acid as internal standard, and protein precipitation with cold acetonitrile, the samples were injected into a diol column, eluted with acetonitrile-1% aqueous acetic acid (25:75) and detected by the ESI-MS system. The optimized method exhibited a good detection limit for both analytes (0.01 and 0.05 microM for GSH and GSSG, respectively). Good linearity was reached in the 0.01-20 microM range for GSH and 0.05-20 microM for GSSG. The mean recoveries of GSH and GSSG were 98.5-100.6% and 105.8-111.5%, respectively. The run-to-run repeatability for retention time and peak area was RSD% 0.06 and 1.75 for GSH and 0.18 and 2.50 for GSSG. The optimized method was applied to GSH and GSSG assay in PBMC analyzing 20 healthy individuals.


Assuntos
Cromatografia Líquida/métodos , Glutationa/sangue , Monócitos/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Etilmaleimida/química , Glutationa/química , Humanos , Oxirredução , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Free Radic Res ; 35(6): 833-41, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11811534

RESUMO

In order to verify the role played by oxidation in the budding of potato tubers (Solanum tuberosum L. cv. Kennebec), the physiological events occurring below bud at 4 degrees C have been studied for a period of 6 months. The low temperature storage induced an increase in the degree of unsaturation and a decrease in the ratio of saturated/unsaturated fatty acids of membrane polar lipids with a subsequent increase of lipid hydroperoxides (LOOH). Cold stress increased both enzymatic antioxidative activities (superoxide dismutase, SOD, E.C.1.15.1.1; catalase, CAT, E.C.1.11.1.6), and alpha-tocopherol levels thus protecting membrane's polyunsaturated lipids. Between 0 and 15 days of storage SOD/CAT ratio, alpha-tocopherol, LOOH levels and the degree of lipid unsaturation showed strong variations. After 30 to 120/150 days the antioxidative system seemed to reach a homeostasis different from that of time 0, accompanied by a constant increase of indole-3-acetic acid (IAA) after 60 days. The antioxidative system, after 150 days, lost its efficiency while LOOH levels were maintained higher than time 0 and IAA concentration was sufficient to allow sprouting.


Assuntos
Temperatura Baixa , Substâncias de Crescimento/biossíntese , Estresse Oxidativo , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/metabolismo , Catalase/metabolismo , Ácidos Graxos/metabolismo , Ácidos Indolacéticos/metabolismo , Peróxidos Lipídicos/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Tempo , alfa-Tocoferol/metabolismo
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