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1.
Braz. j. biol ; 82: e247102, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278491

RESUMO

The current investigation was carried out to estimate the protective effect of aqueous extract of Cheatomorpha gracilis (AEC) against High fat Diet (HFD) induced liver damage in mice. The results of the in vitro study showed that AEC have higher antioxidant capacities in the DPPH and hydroxyl radical-scavenging assays. Indeed, many phenolic compounds (gallic acid, quercetin, naringenin, apigenin, kaempferol and rutin) were identified in the AEC. In the animal studies, during 6 weeks, HFD promoted oxidative stress with a rise level of malonaldehyde (MDA), protein carbonyls (PCOs) levels and a significant decrease of the antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase. Interestingly, the treatment with AEC (250 mg/kg body weight) significantly reduced the effects of HFD disorders on some plasmatic liver biomarkers (AST, ALT and ALP) in addition to, plasmatic proteins inflammatory biomarkers (α2 and ß1 decreases / ß2 and γ globulins increases). It can be suggest that supplementation of MECG displays high potential to quench free radicals and attenuates high fat diet promoted liver oxidative stress and related disturbances.


A presente investigação foi realizada para estimar o efeito protetor do extrato aquoso de Cheatomorpha gracilis (AEC) contra o dano hepático induzido por dieta rica em gordura (HFD) em camundongos. Os resultados do estudo in vitro mostraram que os AEC têm maiores capacidades antioxidantes nos ensaios DPPH e de eliminação de radicais hidroxila. De fato, muitos compostos fenólicos (ácido gálico, quercetina, naringenina, apigenina, kaempferol e rutina) foram identificados no AEC. Nos estudos em animais, durante 6 semanas, HFD promoveu estresse oxidativo com aumento do nível de malonaldeído (MDA), níveis de proteína carbonil (PCOs) e diminuição significativa das atividades de enzimas antioxidantes como superóxido dismutase, catalase e glutationa peroxidase. Curiosamente, o tratamento com AEC (250 mg / kg de peso corporal) reduziu significativamente os efeitos dos distúrbios de HFD em alguns biomarcadores hepáticos plasmáticos (AST, ALT e ALP), além de biomarcadores inflamatórios de proteínas plasmáticas (reduções α2 e ß1 / ß2 e γ aumenta as globulinas). Pode-se sugerir que a suplementação de MECG apresenta alto potencial para extinguir os radicais livres e atenua o estresse oxidativo do fígado promovido pela dieta rica em gordura e distúrbios relacionados.


Assuntos
Animais , Ratos , Extratos Vegetais/farmacologia , Dieta Hiperlipídica/efeitos adversos , Cromatografia Líquida de Alta Pressão , Estresse Oxidativo , Fígado , Antioxidantes/metabolismo
2.
Braz. j. biol ; 82: e246316, 2022. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1249248

RESUMO

Several endemic species of Blaps occur in Tunisia, and the species Blaps nefrauensis nefrauensis has been reported in Moulares (urban zone in west-central Tunisia), where it lives and reproduces in home gardens and old buildings. The aim of this work is to study the life cycle of the darkling beetle, considering both field and laboratory rearing conditions. As a result, the beetle species has different developmental stages (egg, larva, prepupa, pupa, and adult) that last about 15 months. Each year during the same period, adults emerge (early summer) and expire (late autumn), larvae hatch (late summer) and pupate (early summer). There is only one generation per year. Females began laying eggs in late July. The eggs were ovoid, white, and about 2.7 mm in length and 1.5 mm in width. Embryogenesis took an average of nine days. The first instar larvae were at initially only 4.5 mm long and ivory white in color. A brief description of the newly egg hatched larva was provided; thus, the nerve fibers innervating the apical setae in the antennae and ligula were detected. Further light microscopic examination of the embryo before hatching from the egg pointed out that the antennal sensilla are protected during the embryogenesis stage.


Várias espécies endêmicas de Blaps ocorrem na Tunísia, e a espécie Blaps nefrauensis nefrauensis foi relatada em Moulares (zona urbana no centro-oeste da Tunísia), onde vive e se reproduz em jardins domésticos e prédios antigos. O objetivo deste trabalho é estudar o ciclo de vida do besouro escuro, considerando as condições de criação em campo e em laboratório. Como resultado, a espécie de besouro tem diferentes estágios de desenvolvimento (ovo, larva, prepupa, pupa e adulto) que duram cerca de 15 meses. Todos os anos, durante o mesmo período, os adultos emergem (início do verão) e expiram (final do outono), as larvas eclodem (final do verão) e se tornam pupas (início do verão). Existe apenas uma geração por ano. As fêmeas começaram a botar ovos no final de julho. Os ovos eram ovóides, brancos, com cerca de 2,7 mm de comprimento e 1,5 mm de largura. A embriogênese demorou em média nove dias. As larvas de primeiro instar tinham inicialmente apenas 4,5 mm de comprimento e uma cor branca marfim. Foi fornecida uma breve descrição da larva recém-eclodida; assim, as fibras nervosas que inervam as cerdas apicais nas antenas e ligulas foram detectadas. Um exame microscópico de luz posterior do embrião antes da eclosão do ovo mostrou que as sensilas antenais são protegidas durante o estágio de embriogênese.


Assuntos
Animais , Feminino , Besouros , Pupa , Estações do Ano , Larva
3.
Braz. j. biol ; 82: 1-10, 2022. map, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468505

RESUMO

Several endemic species of Blaps occur in Tunisia, and the species Blaps nefrauensis nefrauensis has been reported in Moulares (urban zone in west-central Tunisia), where it lives and reproduces in home gardens and old buildings. The aim of this work is to study the life cycle of the darkling beetle, considering both field and laboratory rearing conditions. As a result, the beetle species has different developmental stages (egg, larva, prepupa, pupa, and adult) that last about 15 months. Each year during the same period, adults emerge (early summer) and expire (late autumn), larvae hatch (late summer) and pupate (early summer). There is only one generation per year. Females began laying eggs in late July. The eggs were ovoid, white, and about 2.7 mm in length and 1.5 mm in width. Embryogenesis took an average of nine days. The first instar larvae were at initially only 4.5 mm long and ivory white in color. A brief description of the newly egg hatched larva was provided; thus, the nerve fibers innervating the apical setae in the antennae and ligula were detected. Further light microscopic examination of the embryo before hatching from the egg pointed out that the antennal sensilla are protected during the embryogenesis stage.


Várias espécies endêmicas de Blaps ocorrem na Tunísia, e a espécie Blaps nefrauensis nefrauensis foi relatada em Moulares (zona urbana no centro-oeste da Tunísia), onde vive e se reproduz em jardins domésticos e prédios antigos. O objetivo deste trabalho é estudar o ciclo de vida do besouro escuro, considerando as condições de criação em campo e em laboratório. Como resultado, a espécie de besouro tem diferentes estágios de desenvolvimento (ovo, larva, prepupa, pupa e adulto) que duram cerca de 15 meses. Todos os anos, durante o mesmo período, os adultos emergem (início do verão) e expiram (final do outono), as larvas eclodem (final do verão) e se tornam pupas (início do verão). Existe apenas uma geração por ano. As fêmeas começaram a botar ovos no final de julho. Os ovos eram ovóides, brancos, com cerca de 2,7 mm de comprimento e 1,5 mm de largura. A embriogênese demorou em média nove dias. As larvas de primeiro instar tinham inicialmente apenas 4,5 mm de comprimento e uma cor branca marfim. Foi fornecida uma breve descrição da larva recém-eclodida; assim, as fibras nervosas que inervam as cerdas apicais nas antenas e ligulas foram detectadas. Um exame microscópico de luz posterior do embrião antes da eclosão do ovo mostrou que as sensilas antenais são protegidas durante o estágio de embriogênese.


Assuntos
Animais , Besouros/anatomia & histologia , Besouros/crescimento & desenvolvimento
4.
Braz. j. biol ; 82: 1-12, 2022. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468550

RESUMO

The current investigation was carried out to estimate the protective effect of aqueous extract of Cheatomorpha gracilis (AEC) against High fat Diet (HFD) induced liver damage in mice. The results of the in vitro study showed that AEC have higher antioxidant capacities in the DPPH and hydroxyl radical-scavenging assays. Indeed, many phenolic compounds (gallic acid, quercetin, naringenin, apigenin, kaempferol and rutin) were identified in the AEC. In the animal studies, during 6 weeks, HFD promoted oxidative stress with a rise level of malonaldehyde (MDA), protein carbonyls (PCOs) levels and a significant decrease of the antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase. Interestingly, the treatment with AEC (250 mg/kg body weight) significantly reduced the effects of HFD disorders on some plasmatic liver biomarkers (AST, ALT and ALP) in addition to, plasmatic proteins inflammatory biomarkers (α2 and β1 decreases / β2 and γ globulins increases). It can be suggest that supplementation of MECG displays high potential to quench free radicals and attenuates high fat diet promoted liver oxidative stress and related disturbances.


A presente investigação foi realizada para estimar o efeito protetor do extrato aquoso de Cheatomorpha gracilis (AEC) contra o dano hepático induzido por dieta rica em gordura (HFD) em camundongos. Os resultados do estudo in vitro mostraram que os AEC têm maiores capacidades antioxidantes nos ensaios DPPH e de eliminação de radicais hidroxila. De fato, muitos compostos fenólicos (ácido gálico, quercetina, naringenina, apigenina, kaempferol e rutina) foram identificados no AEC. Nos estudos em animais, durante 6 semanas, HFD promoveu estresse oxidativo com aumento do nível de malonaldeído (MDA), níveis de proteína carbonil (PCOs) e diminuição significativa das atividades de enzimas antioxidantes como superóxido dismutase, catalase e glutationa peroxidase. Curiosamente, o tratamento com AEC (250 mg / kg de peso corporal) reduziu significativamente os efeitos dos distúrbios de HFD em alguns biomarcadores hepáticos plasmáticos (AST, ALT e ALP), além de biomarcadores inflamatórios de proteínas plasmáticas (reduções α2 e β1 / β2 e γ aumenta as globulinas). Pode-se sugerir que a suplementação de MECG apresenta alto potencial para extinguir os radicais livres e atenua o estresse oxidativo do fígado promovido pela dieta rica em gordura e distúrbios relacionados.


Assuntos
Camundongos , Estresse Oxidativo , Fígado , Gorduras na Dieta/toxicidade , Medicamentos Hepatoprotetores
5.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468692

RESUMO

Abstract Several endemic species of Blaps occur in Tunisia, and the species Blaps nefrauensis nefrauensis has been reported in Moulares (urban zone in west-central Tunisia), where it lives and reproduces in home gardens and old buildings. The aim of this work is to study the life cycle of the darkling beetle, considering both field and laboratory rearing conditions. As a result, the beetle species has different developmental stages (egg, larva, prepupa, pupa, and adult) that last about 15 months. Each year during the same period, adults emerge (early summer) and expire (late autumn), larvae hatch (late summer) and pupate (early summer). There is only one generation per year. Females began laying eggs in late July. The eggs were ovoid, white, and about 2.7 mm in length and 1.5 mm in width. Embryogenesis took an average of nine days. The first instar larvae were at initially only 4.5 mm long and ivory white in color. A brief description of the newly egg hatched larva was provided; thus, the nerve fibers innervating the apical setae in the antennae and ligula were detected. Further light microscopic examination of the embryo before hatching from the egg pointed out that the antennal sensilla are protected during the embryogenesis stage.


Resumo Várias espécies endêmicas de Blaps ocorrem na Tunísia, e a espécie Blaps nefrauensis nefrauensis foi relatada em Moulares (zona urbana no centro-oeste da Tunísia), onde vive e se reproduz em jardins domésticos e prédios antigos. O objetivo deste trabalho é estudar o ciclo de vida do besouro escuro, considerando as condições de criação em campo e em laboratório. Como resultado, a espécie de besouro tem diferentes estágios de desenvolvimento (ovo, larva, prepupa, pupa e adulto) que duram cerca de 15 meses. Todos os anos, durante o mesmo período, os adultos emergem (início do verão) e expiram (final do outono), as larvas eclodem (final do verão) e se tornam pupas (início do verão). Existe apenas uma geração por ano. As fêmeas começaram a botar ovos no final de julho. Os ovos eram ovóides, brancos, com cerca de 2,7 mm de comprimento e 1,5 mm de largura. A embriogênese demorou em média nove dias. As larvas de primeiro instar tinham inicialmente apenas 4,5 mm de comprimento e uma cor branca marfim. Foi fornecida uma breve descrição da larva recém-eclodida; assim, as fibras nervosas que inervam as cerdas apicais nas antenas e ligulas foram detectadas. Um exame microscópico de luz posterior do embrião antes da eclosão do ovo mostrou que as sensilas antenais são protegidas durante o estágio de embriogênese.

6.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468737

RESUMO

Abstract The current investigation was carried out to estimate the protective effect of aqueous extract of Cheatomorpha gracilis (AEC) against High fat Diet (HFD) induced liver damage in mice. The results of the in vitro study showed that AEC have higher antioxidant capacities in the DPPH and hydroxyl radical-scavenging assays. Indeed, many phenolic compounds (gallic acid, quercetin, naringenin, apigenin, kaempferol and rutin) were identified in the AEC. In the animal studies, during 6 weeks, HFD promoted oxidative stress with a rise level of malonaldehyde (MDA), protein carbonyls (PCOs) levels and a significant decrease of the antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase. Interestingly, the treatment with AEC (250 mg/kg body weight) significantly reduced the effects of HFD disorders on some plasmatic liver biomarkers (AST, ALT and ALP) in addition to, plasmatic proteins inflammatory biomarkers (2 and 1 decreases / 2 and globulins increases). It can be suggest that supplementation of MECG displays high potential to quench free radicals and attenuates high fat diet promoted liver oxidative stress and related disturbances.


Resumo A presente investigação foi realizada para estimar o efeito protetor do extrato aquoso de Cheatomorpha gracilis (AEC) contra o dano hepático induzido por dieta rica em gordura (HFD) em camundongos. Os resultados do estudo in vitro mostraram que os AEC têm maiores capacidades antioxidantes nos ensaios DPPH e de eliminação de radicais hidroxila. De fato, muitos compostos fenólicos (ácido gálico, quercetina, naringenina, apigenina, kaempferol e rutina) foram identificados no AEC. Nos estudos em animais, durante 6 semanas, HFD promoveu estresse oxidativo com aumento do nível de malonaldeído (MDA), níveis de proteína carbonil (PCOs) e diminuição significativa das atividades de enzimas antioxidantes como superóxido dismutase, catalase e glutationa peroxidase. Curiosamente, o tratamento com AEC (250 mg / kg de peso corporal) reduziu significativamente os efeitos dos distúrbios de HFD em alguns biomarcadores hepáticos plasmáticos (AST, ALT e ALP), além de biomarcadores inflamatórios de proteínas plasmáticas (reduções 2 e 1 / 2 e aumenta as globulinas). Pode-se sugerir que a suplementação de MECG apresenta alto potencial para extinguir os radicais livres e atenua o estresse oxidativo do fígado promovido pela dieta rica em gordura e distúrbios relacionados.

7.
Braz J Biol ; 82: e246316, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34076171

RESUMO

Several endemic species of Blaps occur in Tunisia, and the species Blaps nefrauensis nefrauensis has been reported in Moulares (urban zone in west-central Tunisia), where it lives and reproduces in home gardens and old buildings. The aim of this work is to study the life cycle of the darkling beetle, considering both field and laboratory rearing conditions. As a result, the beetle species has different developmental stages (egg, larva, prepupa, pupa, and adult) that last about 15 months. Each year during the same period, adults emerge (early summer) and expire (late autumn), larvae hatch (late summer) and pupate (early summer). There is only one generation per year. Females began laying eggs in late July. The eggs were ovoid, white, and about 2.7 mm in length and 1.5 mm in width. Embryogenesis took an average of nine days. The first instar larvae were at initially only 4.5 mm long and ivory white in color. A brief description of the newly egg hatched larva was provided; thus, the nerve fibers innervating the apical setae in the antennae and ligula were detected. Further light microscopic examination of the embryo before hatching from the egg pointed out that the antennal sensilla are protected during the embryogenesis stage.


Assuntos
Besouros , Animais , Feminino , Larva , Pupa , Estações do Ano
8.
Braz J Biol ; 82: e247102, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34161431

RESUMO

The current investigation was carried out to estimate the protective effect of aqueous extract of Cheatomorpha gracilis (AEC) against High fat Diet (HFD) induced liver damage in mice. The results of the in vitro study showed that AEC have higher antioxidant capacities in the DPPH and hydroxyl radical-scavenging assays. Indeed, many phenolic compounds (gallic acid, quercetin, naringenin, apigenin, kaempferol and rutin) were identified in the AEC. In the animal studies, during 6 weeks, HFD promoted oxidative stress with a rise level of malonaldehyde (MDA), protein carbonyls (PCOs) levels and a significant decrease of the antioxidant enzyme activities such as superoxide dismutase, catalase and glutathione peroxidase. Interestingly, the treatment with AEC (250 mg/kg body weight) significantly reduced the effects of HFD disorders on some plasmatic liver biomarkers (AST, ALT and ALP) in addition to, plasmatic proteins inflammatory biomarkers (α2 and ß1 decreases / ß2 and γ globulins increases). It can be suggest that supplementation of MECG displays high potential to quench free radicals and attenuates high fat diet promoted liver oxidative stress and related disturbances.


Assuntos
Dieta Hiperlipídica , Extratos Vegetais , Animais , Antioxidantes/metabolismo , Cromatografia Líquida de Alta Pressão , Dieta Hiperlipídica/efeitos adversos , Fígado , Camundongos , Estresse Oxidativo , Extratos Vegetais/farmacologia
9.
Food Chem Toxicol ; 70: 84-93, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24727051

RESUMO

This study aimed to investigate the potential protective effects of melatonin (Mel) against aluminium-induced neurodegenerative changes in aging Wistar rats (24-28months old). Herein, aluminium chloride (AlCl3) (50mg/kg BW/day) was administered by gavage, and melatonin (Mel) was co-administered to a group of Al-treated rats by an intra-peritoneal injection at a daily dose of 10mg/kg BW for four months. The findings revealed that aluminium administration induced a significant decrease in body weight associated with marked mortality for the old group of rats, which was more pronounced in old Al-treated rats. Behavioural alterations were assessed by 'open fields', 'elevated plus maze' and 'Radial 8-arms maze' tests. The results demonstrated that Mel co-administration alleviated neurobehavioral changes in both old and old Al-treated rats. Melatonin was noted to play a good neuroprotective role, reducing lipid peroxidation (TBARs), and enhancing enzymatic (SOD, CAT and GPx) activities in the brain organs of old control and old Al-treated rats. Mel treatment also reversed the decrease of AChE activity in the brain tissues, which was confirmed by histological sections. Overall, the results showed that Mel administration can induce beneficial effects for the treatment of Al-induced neurobehavioral and neurochemical changes in the central nervous system (CNS).


Assuntos
Envelhecimento/efeitos dos fármacos , Alumínio/toxicidade , Comportamento Animal/efeitos dos fármacos , Melatonina/toxicidade , Doenças Neurodegenerativas/patologia , Acetilcolinesterase/metabolismo , Alumínio/administração & dosagem , Animais , Peso Corporal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Melatonina/administração & dosagem , Doenças Neurodegenerativas/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
10.
Food Chem Toxicol ; 48(6): 1638-43, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20347916

RESUMO

Moderate doses of lithium were chronically administered to mice in order to verify whether the cytoprotective effects of lithium could be in part attributed to a molecular protection conferred by stress proteins/chaperones accumulation. In order to reach serum lithium levels within the common therapeutic values, mice were fed for 6 months on food pellets contained 1 g (L1 group) or 2 g (L2 group) lithium carbonate/kg, resulting in serum concentrations of 0.5 and 0.9 mM Li, respectively. Under these experimental conditions, no clinical side-effects were observed. Urea and creatinine concentrations in serum, lipids peroxidation level and activities of catalase, superoxide-dismutase and glutathione-peroxidase in liver and kidney were not significantly different from control values. Although the expression level of the constitutive HSP73 was not significantly modified, HSP72 was found to be down-regulated in kidney after 1 month. In liver, three protein bands were immunodetected by the anti-GRP94 antibody: 98 kDa and 96 kDa proteins corresponding to more or less glycosylated forms and/or phosphorylated forms of GRP94 and a 80 kDa protein probably being a cleavage product of GRP94. The 96 kDa and 80 kDa proteins were significantly up-regulated in liver of lithium-treated mice as compared to controls.


Assuntos
Compostos de Lítio/administração & dosagem , Fígado/efeitos dos fármacos , Glicoproteínas de Membrana/metabolismo , Isoformas de Proteínas/metabolismo , Animais , Creatinina/sangue , Peroxidação de Lipídeos , Compostos de Lítio/sangue , Fígado/metabolismo , Masculino , Camundongos , Ureia/sangue
11.
Acta Biol Hung ; 60(3): 273-80, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19700386

RESUMO

Lithium salts are efficiently used for treatment of psychiatric disorders. However, prolonged treatment frequently involves adverse side-effects. In the present work, effects of lithium carbonate administration on some biochemical parameters were studied in male mice. Lithium carbonate (20, 40 or 80 mg/kg body weight, corresponding to 3.77, 7.54 or 15.08 mg Li element/kg body weight, respectively) was injected daily for 14 or 28 days. The following parameters were recorded: water consumption, body weight, lithium and testosterone serum concentrations, activities of catalase (CAT), superoxide-dismutase (SOD) and glutathione-peroxidase (GPX) and level of lipid peroxidation (expressed as TBARS) in liver was performed. Lithium treatment, especially at the highest dose for 28 days, was found to induce weight gain, polydipsia and a significant decrease of plasma testosterone level. Lipid peroxidation level and activities of SOD and GPX were increased in liver which suggests a perturbation of the antioxidative status. Our results indicate that subchronic exposure to lithium, which induces weight gain and polydipsia under our experimental conditions, also damages the male reproductive system and triggers an oxidative stress in the liver.


Assuntos
Carbonato de Lítio/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Carbonato de Lítio/administração & dosagem , Carbonato de Lítio/efeitos adversos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testosterona/sangue , Água/metabolismo
12.
Neurochem Res ; 34(3): 453-62, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18688712

RESUMO

SH-SY5Y cells, derived from a human neuroblastoma, were submitted to short- or long-term exposures to lithium carbonate concentrations ranging from 0.5 to 8 mM. Short-term exposures (4 days) to concentrations higher than 6 mM were found to reduce cell growth rate while exposure to 8 mM resulted in significant cell mortality. These ranges of concentrations induced an overexpression of (1) the HSP27 stress protein, (2) a 108 kDa protein (P108) recognized by an anti-phospho-HSP27(Ser78) antibody, and probably corresponding to a phosphorylated HSP27 tetramer, (3) a 105 kDa protein (P105), possible glycosylated or phosphorylated form of the GRP94 stress protein and (4) a phosphorylated (inactivated) form of glycogen synthase kinase (GSK3alpha/beta) SH-SY5Y cells, when cultured in the presence of 0.5 mM lithium for 25 weeks, displayed interesting features as compared to controls: (1) higher cell growth rate, (2) increased resistance toward the inhibitory effects of high lithium concentrations on cell proliferation, (3) lower basal level of lipid peroxidation (TBARS) and improved tolerance to oxidative stress induced by high lithium concentrations, (5) reduced expression of monomeric HSP27 versus an increase of corresponding tetrameric protein (P108) and (6) overexpression of a 105 kDa protein (P105). In conclusion, our study suggests that chronic treatment (over several months) by therapeutic relevant lithium concentrations could favour neurogenesis, decrease the vulnerability of neuronal cells to oxidative stress and induce posttranslational changes of molecular chaperones.


Assuntos
Antimaníacos/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteínas de Choque Térmico/biossíntese , Carbonato de Lítio/farmacologia , Chaperonas Moleculares/biossíntese , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/metabolismo , Proteínas de Choque Térmico HSC70/biossíntese , Proteínas de Choque Térmico HSP27/biossíntese , Proteínas de Choque Térmico HSP72/biossíntese , Proteínas de Choque Térmico HSP90/biossíntese , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Glicoproteínas de Membrana/biossíntese , Fatores de Tempo
13.
Toxicol Mech Methods ; 18(7): 597-603, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20020860

RESUMO

ABSTRACT The purpose of this study, carried out in Wistar rats, was to evaluate the protective effect of dietary restriction (performed by intermittent fasting) against oxidative stress induced by a low concentration of nickel chloride in kidney, liver, uterus, and ovary. Lipid peroxidation (TBARS), catalase activity, and the levels of vitamins E and A in the blood were investigated in rats feed for 1 month either daily (N) or 1 day over two (intermittent fasting, IF) and then injected (NNi, IFNi) or not with nickel chloride (30 mumoles/kg body weight/day) for 10 days. Ni induced a significant increase of TBARS in organs of N rats. Intermittent fasting alone or associated to nickel treatment did not result in TBARS change in IF and IFNi rats. Catalase activity levels were found to be similar in N and IF rats. In Ni-treated rats a transient increase of catalase activity appeared at day 1 in the kidney and days 1 and 3 in the liver. Then, catalase activity was found to be inhibited until day 10. In the uterus and ovary, catalase activity was always found to be inhibited. In IFNi rats, no significant increase of catalase activity was observed as compared to IF rats. Vitamin E was inhibited from the 1st to the 10th day in Ni rats, whereas no significant changes were noted in IFNi rats. A moderate decrease of vitamin A was only found at days 1 and 3 in Ni rats. In conclusion, intermittent fasting is able to protect from oxidative stress induced by low concentration of Ni, but catalase and Vitamins E and A do not seem to be involved.

14.
Biochim Biophys Acta ; 1773(7): 1107-15, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17512992

RESUMO

To unveil some molecular mechanisms underlying lithium toxicity, expression changes of stress-related genes or proteins were analysed in A549 cells, cultured for 3 days in presence of lithium. A dose-dependent cell-growth inhibition was found for concentrations ranging from 2 (toxicity threshold) to 12 mM (lethality threshold). cDNA arrays technology was used to analyse effects of 5 and 10 mM lithium. Among genes involved in cell cycle regulation, proliferating cell nuclear antigen (PCNA) was down-regulated and cyclin kinase inhibitor p21 (CDKN1A), up-regulated. Genes of paraoxonase 2, known to prevent LDL lipid peroxidation, and of catalase and SOD were found to be down-regulated whereas genes of cytochrome P450 (CYP2F1, CYP2E1) were up-regulated. This probably results in higher intracellular levels of reactive oxygen species and account for increased levels of lipid peroxidation commonly associated with lithium exposure. Moreover, lithium was found to down-regulate genes coding for anti-apoptotic gene BAG-1 and for most of the molecular chaperones (HSP, GRP). This might account for lithium toxicity since these proteins are critical for cell survival. At translational level, a 105 kDa protein was found to be over-expressed. This protein was recognized by the anti-GRP94, anti-KDEL and anti-phosphoserine monoclonal antibodies suggesting that, lithium could induce post-translational modifications of GRP94 phosphorylation. Using tunicamycin and thapsigargin, it was concluded that lithium effects are not related to defect in N-linked glycosylation and/or to changes in calcium homeostasis.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Lítio , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Perfilação da Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Lítio/farmacologia , Lítio/toxicidade , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Fisiológico
15.
Hum Exp Toxicol ; 25(5): 243-50, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16758766

RESUMO

Lithium therapy, mainly used in curing some psychiatric diseases, is responsible for numerous undesirable side effects. The present study is a contribution to the understanding of the pathophysiological mechanisms underlying lithium toxicity. Male and female mature rats were divided into three batches and fed commercial pellets: one batch was the control and the second and third batches were given 2 g (Li1) and 4 g (Li2) of lithium carbonate/kg of food/day, respectively. After 7, 14, 21 and 28 days, serum levels of free tri-iodothyronine (FT3), thyroxine (FT4), testosterone and estradiol were measured. Attention was also paid to growth rate and a histological examination of testes or vaginal mucosa was carried out. In treated rats, a dose-dependent loss of appetite and a decrease in growth rate were observed, together with symptoms of polydypsia, polyuria and diarrhea. Lithium serum concentrations increased from 0.44 mM (day 7) to 1.34 mM (day 28) in Li1 rats and from 0.66 to 1.45 mM (day 14) in Li2 rats. Li2 treatment induced a high mortality after 14 days, reaching 50-60% in female and male animals. From these data, the LD50 (14 days Li2 chronic treatment) was calculated to be about 0.3 g/day per kilogram of animal, leading to Li serum concentrations of about 1.4 mM. A significant decrease of FT3 and FT4 was observed in treated rats. This effect appeared immediately for the highest dose and was more pronounced for FT3, resulting in an increase of the FT4/FT3 ratio. In males, testosterone decreased and spermatogenesis was stopped. Conversely, in females, estradiol increased in a dose-dependent manner as the animals were blocked in the diestrus phase at day 28. This finding supports a possible antagonistic effect of lithium on the estradiol receptors.


Assuntos
Lítio/toxicidade , Testículo/efeitos dos fármacos , Glândula Tireoide/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Estradiol/sangue , Feminino , Lítio/sangue , Lítio/farmacocinética , Masculino , Ratos , Ratos Wistar , Espermatogênese/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Testosterona/sangue , Glândula Tireoide/metabolismo , Tiroxina/sangue , Tri-Iodotironina/sangue
16.
J Biochem Mol Toxicol ; 19(1): 12-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15736156

RESUMO

The present study deals with the effects of Ni on the expression level of three stress proteins, namely, the cytosolic HSP72 and HSP73, and the reticulum-associated GRP94. Experiments were carried out on "Wistar'' female rats daily injected with 4 mg NiCl2 per kg body weight for 1, 3, 5, and 10 days. Another set of experiments were carried out using cell lines, derived from the monkey kidney (COS-7), and from human tumors of the lung (A549) and liver (HepG2). Cells were cultured for 4 days in the permanent presence of 100, 200, or 400 microM NiCl2. In control rats, stress proteins pattern was found to be tissue specific: two protein bands of 96 and 94 kDa were immunodetected with the anti-GRP94 antibody in kidney and liver extracts, whereas only the 96 kDa band was present in ovary extracts. HSP73 was present in kidney, liver, and ovary whereas HSP72 was only found in kidney. In kidney of nickel-treated animals, HSP73 and the 96 kDa proteins were overexpressed whereas HSP72 was strongly down regulated. No such effect was observed in liver or ovary. Similarly, in nickel-treated cell lines, HSP72 was downregulated and GRP94 (96 kDa protein) was overexpressed. HSP73 expression appeared moderately increased in A549 cells but decreased in COS-7 cells. Because long-term caloric restriction was reported to reduce free radical generation in cells, the effect of 1 month food restriction (50%) was tested in rats as a possible way to lower oxidative damages induced by Ni. No significant effect on HSP expression was observed.


Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico/metabolismo , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Níquel/envenenamento , Ovário/efeitos dos fármacos , Ração Animal , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Chlorocebus aethiops , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico HSC70 , Proteínas de Choque Térmico HSP72 , Humanos , Rim/metabolismo , Fígado/metabolismo , Ovário/metabolismo , Ratos , Ratos Wistar
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