RESUMO
The aim of this work was to evaluate possible mechanisms involved in the protective effect of N-acetyl-L-cysteine (NAC) on hepatic endocrine-metabolic, oxidative stress, and inflammatory changes in prediabetic rats. For that, normal male Wistar rats (60 days old) were fed for 21 days with 10% sucrose in their drinking water and 5 days of NAC administration (50 mg/kg, i.p.) and thereafter, we determined: serum glucose, insulin, transaminases, uric acid, and triglyceride levels; hepatic fructokinase and glucokinase activities, glycogen content, lipogenic gene expression; enzymatic and non-enzymatic oxidative stress, insulin signaling pathway, and inflammatory markers. Results showed that alterations evinced in sucrose-fed rats (hypertriglyceridemia, hyperinsulinemia, and high liver fructokinase activity together with increased liver lipogenic gene expression and oxidative stress and inflammatory markers) were prevented by NAC administration. P-endothelial nitric oxide synthase (P-eNOS)/eNOS and pAKT/AKT ratios, decreased by sucrose ingestion, were restored after NAC treatment. In conclusion, the results suggest that NAC administration improves glucose homeostasis, oxidative stress, and inflammation in prediabetic rats probably mediated by modulation of the AKT/NOS pathway. Administration of NAC may be an effective complementary strategy to alleviate or prevent oxidative stress and inflammatory responses observed in type 2 diabetes at early stages of its development (prediabetes).
Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Estado Pré-Diabético , Ratos , Masculino , Animais , Acetilcisteína/farmacologia , Acetilcisteína/metabolismo , Estado Pré-Diabético/tratamento farmacológico , Ratos Wistar , Diabetes Mellitus Tipo 2/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sacarose/farmacologia , Estresse Oxidativo , Insulina/metabolismo , Transdução de Sinais , Glucose/farmacologia , Óxido Nítrico/metabolismoRESUMO
This investigation aimed to assess the effect of N-acetylcysteine (NAC) as an adjuvant treatment to alleviate visceral leishmaniasis (VL). The present work includes both blinded randomized clinical intervention and experimental in vitro studies. The clinical trial included 60 patients with VL randomly allocated into two groups: a test group (n = 30) treated with meglumine antimoniate plus NAC (SbV + NAC) and a control group (n = 30) treated with meglumine antimoniate only (SbV). The primary outcome was clinical cure (absence of fever, spleen and liver sizes reduction, and hematological improvement) in 180 days. The cure rate did not differ between the groups; both groups had similar results in all readout indices. The immunological parameters of the patients treated with SbV + NAC showed higher sCD40L in sera during treatment, and the levels of sCD40L were negatively correlated with Interleukin-10 (IL-10) serum levels. In addition, data estimation showed a negative correlation between the sCD40L levels and the spleen size in patients with VL. For the in vitro experiments, peripheral blood mononuclear cells (PBMCs) or PBMC-derived macrophages from healthy donors were exposed to soluble Leishmania antigen (SLA) or infected with stationary promastigotes of Leishmania infantum in the presence or absence of NAC. Results revealed that NAC treatment of SLA-stimulated PBMCs reduces the frequency of monocytes producing IL-10 and lowers the frequency of CD4+ and CD8+ T cells expressing (pro-)inflammatory cytokines. Together, these results suggest that NAC treatment may modulate the immune response in patients with VL, thus warranting additional investigations to support its case use as an adjuvant to antimony therapy for VL.
Assuntos
Leishmania infantum , Leishmaniose Visceral , Humanos , Acetilcisteína/farmacologia , Acetilcisteína/uso terapêutico , Adjuvantes Imunológicos/uso terapêutico , Imunidade , Interleucina-10 , Leishmaniose Visceral/tratamento farmacológico , Leucócitos MononuclearesRESUMO
The disruption of neurodevelopment is a hypothesis for the emergence of schizophrenia. Some evidence supports the hypothesis that a redox imbalance could account for the developmental impairments associated with schizophrenia. Additionally, there is a deficit in glutathione (GSH), a main antioxidant, in this disorder. The injection of metilazoximetanol acetate (MAM) on the 17th day of gestation in Wistar rats recapitulates the neurodevelopmental and oxidative stress hypothesis of schizophrenia. The offspring of rats exposed to MAM treatment present in early adulthood behavioral and neurochemical deficits consistent with those seen in schizophrenia. The present study investigated if the acute and chronic (250 mg/kg) treatment during adulthood with N-acetyl-L-cysteine (NAC), a GSH precursor, can revert the behavioral deficits [hyperlocomotion, prepulse inhibition (PPI), and social interaction (SI)] in MAM rats and if the NAC-chronic-effects could be canceled by L-arginine (250 mg/kg, i.p, for 5 days), nitric oxide precursor. Analyses of markers involved in the inflammatory response, such as astrocytes (glial fibrillary acid protein, GFAP) and microglia (binding adapter molecule 1, Iba1), and parvalbumin (PV) positive GABAergic, were conducted in the prefrontal cortex [PFC, medial orbital cortex (MO) and prelimbic cortex (PrL)] and dorsal and ventral hippocampus [CA1, CA2, CA3, and dentate gyrus (DG)] in rats under chronic treatment with NAC. MAM rats showed decreased time of SI and increased locomotion, and both acute and chronic NAC treatments were able to recover these behavioral deficits. L-arginine blocked NAC behavioral effects. MAM rats presented increases in GFAP density at PFC and Iba1 at PFC and CA1. NAC increased the density of Iba1 cells at PFC and of PV cells at MO and CA1 of the ventral hippocampus. The results indicate that NAC recovered the behavioral deficits observed in MAM rats through a mechanism involving nitric oxide. Our data suggest an ongoing inflammatory process in MAM rats and support a potential antipsychotic effect of NAC.
RESUMO
In this study, we examined the potential use of N-acetyl-L-cysteine (NAC) in association with a polyvalent antivenom and as stand-alone therapy to reduce the acute local and systemic effects induced by Lachesis muta muta venom in rats. Male Wistar rats (300-350 g) were exposed to L. m. muta venom (1.5 mg/kg - i.m.) and subsequently treated with anti-Bothrops/Lachesis serum (antivenom:venom ratio 1:3 'v/w' - i.p.) and NAC (150 mg/kg - i.p.) separately or in association; the animals were monitored for 120 min to assess changes in temperature, locomotor activity, local oedema formation and the prevalence of haemorrhaging. After this time, animals were anesthetized in order to collect blood samples through intracardiac puncture and then euthanized for collecting tissue samples; the hematological-biochemical and histopathological analyses were performed through conventional methods. L. m. muta venom produced pronounced local oedema, subcutaneous haemorrhage and myonecrosis, with both antivenom and NAC successfully reducing the extent of the myonecrotic lesion when individually administered; their association also prevented the occurrence of subcutaneous haemorrhage. Venom-induced creatine kinase (CK) release was significantly prevented by NAC alone or in combination with antivenom; NAC alone failed to reduce the release of hepatotoxic (alanine aminotransferase) and nephrotoxic (creatinine) serum biomarkers induced by L. m. muta venom. Venom induced significant increase of leucocytes which was also associated with an increase of neutrophils, eosinophils and monocytes; antivenom and NAC partially reduced these alterations, with NAC alone significantly preventing the increase of eosinophils whereas neither NAC or antivenom prevented the increase in monocytes. Venom did not induce changes in the erythrogram parameters. In the absence of a suitable antivenom, NAC has the potential to reduce a number of local and systemic effects caused by L. m. muta venom.
Assuntos
Venenos de Crotalídeos , Viperidae , Acetilcisteína/uso terapêutico , Animais , Antivenenos/uso terapêutico , Venenos de Crotalídeos/toxicidade , Masculino , Ratos , Ratos Wistar , Venenos de Víboras/toxicidadeRESUMO
Introduction: Several studies in the literature have evaluated the role of oxidative stress and adjuvant therapies for X-linked adrenoleukodystrophy (X-ALD). Here, we investigated whether n-acetyl-L-cysteine (NAC) and rosuvastatin (RSV) could influence the generation of reactive species, redox status and nitrative stress in fibroblasts from asymptomatic patients with X-ALD. Methods: Skin biopsy samples were cultured and treated for 2 hours (37 °C) with NAC and RSV. Results: X-ALD fibroblasts generated high levels of reactive oxygen species. These levels were significantly lower in fibroblasts treated with NAC and RSV relative to untreated samples. The X-ALD fibroblasts from asymptomatic patients also had higher catalase activity, and only NAC was able to increase enzyme activity in the samples. Conclusions: Our results indicated that NAC and RSV were able to improve oxidative stress parameters in fibroblasts from asymptomatic patients with X-ALD, showing that adjuvant antioxidant therapy may be a promising treatment strategy for asymptomatic patients with this disease. (AU)
Assuntos
Humanos , Masculino , Feminino , Acetilcisteína , Estresse Oxidativo , Adrenoleucodistrofia/terapia , Rosuvastatina Cálcica , FibroblastosRESUMO
In the present work, we obtained polymeric diacetylene liposomes that can associate N-Acetyl-l-Cysteine (NAC), a broad spectrum mucolytic. The reason for studying these formulations is that they could be applied in the future as NAC delivery systems, with a possible dose reduction but maintaining its effect. Liposomes used herein are obtained by a photopolymerization reaction, thus gaining stability and rigidity. Lipids belonging to lung surfactant were added in different ratios to the formulations in order to maximize its possible interaction with the lung tissue. Because of lipopolymer stability, the oral or nasal route could be appropriated. This formulation could efficiently transport NAC to exert its mucolytic activity and help in diseases such as cystic fibrosis, which has abnormal mucus production. Also, this type of treatment could be useful in other types of diseases, interacting with the mucus layer and making the lung tissue more permeable to other therapies. Formulations so obtained presented high levels of polymerization. Also, they present small hollow fibers structures with a high number of polymeric units. These types of arrangements could present advantages in the field of drug delivery, giving the possibility of a controlled release. Lipopolymers with lipids from lung surfactant associated with NAC are promising complexes in order to treat not only respiratory illnesses. The stability of the formulation would allow its inoculation through other routes such as the oral one, helping the reposition of NAC as an antioxidant drug. Finally, these formulations are non-toxic and easy to produce.
Assuntos
Acetilcisteína/química , Fibrose Cística/tratamento farmacológico , Lipídeos/farmacologia , Polímeros/farmacologia , Surfactantes Pulmonares/química , Células A549 , Sobrevivência Celular/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipídeos/química , Tamanho da Partícula , Polímeros/química , Propriedades de SuperfícieRESUMO
AIMS: To investigate the effect of long-term N-acetyl-l-cysteine (NAC) treatment in Wistar rats subjected to renal ischemia and reperfusion (IR) and a chronic highsodium diet (HSD). MAIN METHODS: Adult male Wistar rats received an HSD (8.0% NaCl) or a normalsodium diet (NSD; 1.3% NaCl) and NAC (600â¯mg/L) or normal drinking water starting at 8â¯weeks of age. At 11â¯weeks of age, the rats from both diet and NAC or water treatment groups underwent renal IR or Sham surgery and were followed for 10â¯weeks. The study consisted of six animal groups: NSDâ¯+â¯Shamâ¯+â¯water; NSDâ¯+â¯IRâ¯+â¯water; NSDâ¯+â¯IRâ¯+â¯NAC; HSDâ¯+â¯Shamâ¯+â¯water; HSDâ¯+â¯IRâ¯+â¯water; and HSDâ¯+â¯IRâ¯+â¯NAC. KEY FINDINGS: Tail blood pressure (tBP) increased with IR and NAC treatment in the NSD group but not in the HSD group. The serum creatinine level was higher after NAC treatment in both diet groups, and creatinine clearance was decreased in only the HSDâ¯+â¯IRâ¯+â¯NAC group. Albuminuria increased in the HSDâ¯+â¯IRâ¯+â¯water group and decreased in the HSDâ¯+â¯IRâ¯+â¯NAC group. Kidney mass was increased in the HSDâ¯+â¯IR group and decreased with NAC treatment. Renal fibrosis was prevented with NAC treatment and cardiac fibrosis was decreased with NAC treatment in the HSDâ¯+â¯IR group. SIGNIFICANCE: NAC treatment promoted structural improvements, such as decreased albuminuria and fibrosis, in the kidney and heart. However, NAC could not recover kidney function or blood pressure from the effects of IR associated with an HSD. Therefore, in general, long-term NAC treatment is not effective and is deleterious to recovery of function after kidney injury.
Assuntos
Acetilcisteína/farmacologia , Isquemia Encefálica/fisiopatologia , Rim/irrigação sanguínea , Traumatismo por Reperfusão/fisiopatologia , Cloreto de Sódio na Dieta/efeitos adversos , Injúria Renal Aguda/prevenção & controle , Animais , Pressão Sanguínea/efeitos dos fármacos , Isquemia Encefálica/metabolismo , Sequestradores de Radicais Livres/farmacologia , Isquemia/etiologia , Isquemia/metabolismo , Isquemia/patologia , Isquemia/fisiopatologia , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Ratos , Ratos Wistar , Reperfusão/métodos , Traumatismo por Reperfusão/metabolismo , Cloreto de Sódio na Dieta/administração & dosagemRESUMO
X-linked adrenoleukodystrophy (X-ALD) is an inherited neurometabolic disorder caused by disfunction of the ABCD1 gene, which encodes a peroxisomal protein responsible for the transport of the very long-chain fatty acids from the cytosol into the peroxisome, to undergo ß-oxidation. The mainly accumulated saturated fatty acids are hexacosanoic acid (C26:0) and tetracosanoic acid (C24:0) in tissues and body fluids. This peroxisomal disorder occurs in at least 1 out of 20,000 births. Considering that pathophysiology of this disease is not well characterized yet, and glial cells are widely used in studies of protective mechanisms against neuronal oxidative stress, we investigated oxidative damages and inflammatory effects of vesicles containing lecithin and C26:0, as well as the protection conferred by N-acetyl-L-cysteine (NAC), trolox (TRO), and rosuvastatin (RSV) was assessed. It was verified that glial cells exposed to C26:0 presented oxidative DNA damage (measured by comet assay and endonuclease III repair enzyme), enzymatic oxidative imbalance (high catalase activity), nitrative stress [increased nitric oxide (NO) levels], inflammation [high Interleukin-1beta (IL-1ß) levels], and induced lipid peroxidation (increased isoprostane levels) compared to native glial cells without C26:0 exposure. Furthermore, NAC, TRO, and RSV were capable to mitigate some damages caused by the C26:0 in glial cells. The present work yields experimental evidence that inflammation, oxidative, and nitrative stress may be induced by hexacosanoic acid, the main accumulated metabolite in X-ALD, and that antioxidants might be considered as an adjuvant therapy for this severe neurometabolic disease.
Assuntos
Acetilcisteína/farmacologia , Cromanos/farmacologia , Ácidos Graxos/farmacologia , Inflamação/patologia , Neuroglia/patologia , Estresse Nitrosativo , Estresse Oxidativo , Rosuvastatina Cálcica/farmacologia , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Vesículas Citoplasmáticas/metabolismo , Dano ao DNA , Interleucina-1beta/metabolismo , Isoprostanos/metabolismo , Neuroglia/metabolismo , Fármacos Neuroprotetores/farmacologia , Nitratos/metabolismo , Nitritos/metabolismo , Estresse Nitrosativo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , RatosRESUMO
Introduction: Homocysteine (Hcy) tissue accumulation occurs in a metabolic disease characterized biochemically by cystathionine ß-synthase (CBS) deficiency and clinically by mental retardation, vascular problems, and skeletal abnormalities. Previous studies indicate the occurrence of DNA damage secondary to hyperhomocysteinemia and it was observed that DNA damage occurs in leukocytes from CBS-deficient patients. This study aimed to investigate whether an oxidative mechanism could be involved in DNA damage previously found and investigated the in vitro effect of N-acety-L-cysteine (NAC) on DNA damage caused by high Hcy levels. Methods: We evaluated a biomarker of oxidative DNA damage in the urine of CBSdeficient patients, as well as the in vitro effect of NAC on DNA damage caused by high levels of Hcy. Moreover, a biomarker of lipid oxidative damage was also measured in urine of CBS deficient patients. Results: There was an increase in parameters of DNA (8-oxo-7,8-dihydro-2'- deoxyguanosine) and lipid (15-F2t-isoprostanes levels) oxidative damage in CBS-deficient patients when compared to controls. In addition, a significant positive correlation was found between 15-F2t-isoprostanes levels and total Hcy concentrations. Besides, an in vitro protective effect of NAC at concentrations of 1 and 5 mM was observed on DNA damage caused by Hcy 50 µM and 200 µM. Additionally, we showed a decrease in sulfhydryl content in plasma from CBS-deficient patients when compared to controls. Discussion: These results demonstrated that DNA damage occurs by an oxidative mechanism in CBS deficiency together with lipid oxidative damage, highlighting the NAC beneficial action upon DNA oxidative process, contributing with a new treatment perspective of the patients affected by classic homocystinuria.
Assuntos
Humanos , Feminino , Criança , Adolescente , Adulto , Adulto Jovem , Acetilcisteína/farmacologia , Dano ao DNA , Estresse Oxidativo , Cistationina/metabolismo , Desoxiguanosina/urina , Homocistinúria/genética , Antioxidantes/farmacologia , Biomarcadores/urina , Estudos de Casos e Controles , Creatinina/urina , Ensaio Cometa , Cistationina/biossíntese , Cistationina/sangue , Isoprostanos/análise , Desoxiguanosina/análogos & derivados , Homocisteína/sangue , Homocistinúria/sangueRESUMO
Using an iron overload mouse model, we explored the protective effect of deferasirox (DFX) and N-acetyl-L-cysteine (NAC) on injured bone marrow hematopoietic stem/progenitor cells (HSPC) induced by iron overload. Mice were intraperitoneally injected with 25 mg iron dextran every 3 days for 4 weeks to establish an iron overload (Fe) model. DFX or NAC were co-administered with iron dextran in two groups of mice (Fe+DFX and Fe+NAC), and the function of HSPCs was then examined. Iron overload markedly decreased the number of murine HSPCs in bone marrow. Subsequent colony-forming cell assays showed that iron overload also decreased the colony forming capacity of HSPCs, the effect of which could be reversed by DFX and NAC. The bone marrow hematopoiesis damage caused by iron overload could be alleviated by DFX and NAC.
Assuntos
Animais , Masculino , Acetilcisteína/farmacologia , Triazóis/farmacologia , Benzoatos/farmacologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Quelantes de Ferro/farmacologia , Sequestradores de Radicais Livres/farmacologia , Sobrecarga de Ferro/prevenção & controle , Substâncias Protetoras/farmacologia , Valores de Referência , Fatores de Tempo , Reprodutibilidade dos Testes , Resultado do Tratamento , Espécies Reativas de Oxigênio/análise , Ensaio de Unidades Formadoras de Colônias , Modelos Animais de Doenças , Citometria de Fluxo , Hematopoese/efeitos dos fármacos , Camundongos Endogâmicos C57BLRESUMO
Introduction: Recent evidence shows that oxidative stress seems to be related with the pathophysiology of X-linked adrenoleukodystrophy (X-ALD), a neurodegenerative disorder. Methods: In the present study, the in vitro effect of N-acetyl-L-cysteine (NAC) on glutathione (GSH) and sulfhydryl levels in X-ALD patients was evaluated. Results: A significant reduction of GSH and sulfhydryl content was observed in X-ALD patients compared to the control group. Furthermore, 5 mM of NAC, in vitro, led to an increase in GSH content and sulfhydryl groups in these patients. Conclusion: These data probably indicate that an adjuvant therapy with the antioxidant NAC could improve the oxidative imbalance in X-ALD patients(AU)
Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Acetilcisteína/farmacologia , Adrenoleucodistrofia/fisiopatologia , Glutationa/deficiência , Compostos de Sulfidrila/metabolismo , Adrenoleucodistrofia/tratamento farmacológico , Oxirredução/efeitos dos fármacos , Estresse OxidativoRESUMO
The primary S-nitrosothiol, S-nitroso-N-acetylcysteine (SNAC) is a nitric oxide donor with potential pharmaceutical applications for the oral treatment of hepatic steatosis and cirrhosis and for protection against gastric acid-peptic disorders. However, its low thermal stability precludes the preparation of stable dosage forms based on presynthesized SNAC. In this study, we describe an innovative strategy for the oral administration of SNAC based on its intratablet formation via the S-nitrosation reaction of its parent stable thiol, N-acetyl-L-cysteine by nitrous acid during the absorption of water by the tablet. The proposed strategy allows for the manufacturing of thermally stable oral dosage forms for the controlled release of SNAC in the enteric medium.
Assuntos
Doadores de Óxido Nítrico/administração & dosagem , Doadores de Óxido Nítrico/química , Compostos Nitrosos/química , S-Nitrosotióis/administração & dosagem , S-Nitrosotióis/química , Acetilcisteína/química , Acetilcisteína/farmacologia , Administração Oral , Química Farmacêutica , Preparações de Ação Retardada , Nitrosação , Ácido Nitroso/química , Comprimidos/química , Água/químicaRESUMO
Background: N-acetyl-L-cysteine (NAC) is a low molecular weight thiol studied as an antioxidant for stallion semen preservation without changes on sperm viability. Equine seminal plasma is rich in sulfur proteins (cysteine residues) named CRISPS, which, when combined with sulfur-containing antioxidants, can enhance the appearance of DNA lesions. The aim of this study was to assess and compare the effect of different concentrations of NAC by evaluating motility, membrane function and sperm chromatin integrity of equine semen cooled at 5C in 50% of seminal plasma. Materials, Methods & Results: Nine ejaculates from 9 stallions were divided into 4 aliquots, diluted and divided in nonsupplemented skim milk group (0.0 mM), or supplemented with 5.0, 2.5 and 0.5 mM NAC. Evaluations were made at 0 h, 24 h and 48 h of cooling, except for motility which was evaluated only up to 24 h. The 0.5 (59.7 M2) and 5.0 mM NAC (55.5 M2) groups showed similar areas of sperm chromatin dispersion among all groups. However, the area of chromatin dispersion between the non-supplemented group was higher = 65.3 M2 than the group supplemented with 2.5 mM. The percentage of cells with a functional plasma membrane was similar between supplemented and non-supplemented (0.0 mM) groups, but higher (P 0.05) in the 0.5 mM NAC (39.7 and 39.8%, respectively) than that of 2.5 mM (34.5%) and 5.0 mM [...](AU)
Assuntos
Animais , Masculino , Sêmen/fisiologia , Cavalos/fisiologia , Cromatina/fisiologia , Motilidade dos Espermatozoides/fisiologia , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Dano ao DNA/fisiologiaRESUMO
Background: N-acetyl-L-cysteine (NAC) is a low molecular weight thiol studied as an antioxidant for stallion semen preservation without changes on sperm viability. Equine seminal plasma is rich in sulfur proteins (cysteine residues) named CRISPS, which, when combined with sulfur-containing antioxidants, can enhance the appearance of DNA lesions. The aim of this study was to assess and compare the effect of different concentrations of NAC by evaluating motility, membrane function and sperm chromatin integrity of equine semen cooled at 5C in 50% of seminal plasma. Materials, Methods & Results: Nine ejaculates from 9 stallions were divided into 4 aliquots, diluted and divided in nonsupplemented skim milk group (0.0 mM), or supplemented with 5.0, 2.5 and 0.5 mM NAC. Evaluations were made at 0 h, 24 h and 48 h of cooling, except for motility which was evaluated only up to 24 h. The 0.5 (59.7 M2) and 5.0 mM NAC (55.5 M2) groups showed similar areas of sperm chromatin dispersion among all groups. However, the area of chromatin dispersion between the non-supplemented group was higher = 65.3 M2 than the group supplemented with 2.5 mM. The percentage of cells with a functional plasma membrane was similar between supplemented and non-supplemented (0.0 mM) groups, but higher (P 0.05) in the 0.5 mM NAC (39.7 and 39.8%, respectively) than that of 2.5 mM (34.5%) and 5.0 mM [...]
Assuntos
Masculino , Animais , Análise do Sêmen/veterinária , Cavalos/fisiologia , Cromatina/fisiologia , Motilidade dos Espermatozoides/fisiologia , Preservação do Sêmen/métodos , Sêmen/fisiologia , Dano ao DNA/fisiologiaRESUMO
OBJECTIVE: This study was performed to determine the effect of N-acetyl-L-cysteine, a modified sulfur-containing amino acid that acts as a strong cellular antioxidant, on the response to environmental stressors and on aging in C. elegans. METHOD: The survival of worms under oxidative stress conditions induced by paraquat was evaluated with and without in vivo N-acetyl-L-cysteine treatment. The effect of N-acetyl-L-cysteine on the response to other environmental stressors, including heat stress and ultraviolet irradiation (UV), was also monitored. To investigate the effect on aging, we examined changes in lifespan, fertility, and expression of age-related biomarkers in C. elegans after N-acetyl-L-cysteine treatment. RESULTS: Dietary N-acetyl-L-cysteine supplementation significantly increased resistance to oxidative stress, heat stress, and UV irradiation in C. elegans. In addition, N-acetyl-L-cysteine supplementation significantly extended both the mean and maximum lifespan of C. elegans. The mean lifespan was extended by up to 30.5% with 5 mM N-acetyl-L-cysteine treatment, and the maximum lifespan was increased by 8 days. N-acetyl-L-cysteine supplementation also increased the total number of progeny produced and extended the gravid period of C. elegans. The green fluorescent protein reporter assay revealed that expression of the stress-responsive genes, sod-3 and hsp-16.2, increased significantly following N-acetyl-L-cysteine treatment. CONCLUSION: N-acetyl-L-cysteine supplementation confers a longevity phenotype in C. elegans, possibly through increased resistance to environmental stressors. .
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Feminino , Humanos , Masculino , Diabetes Mellitus/prevenção & controle , Acessibilidade aos Serviços de Saúde , Apoio Social , Bangladesh/etnologia , Agentes Comunitários de Saúde , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/etnologia , Grupos Focais , Comportamentos Relacionados com a Saúde , Pesquisas sobre Atenção à Saúde , Conhecimentos, Atitudes e Prática em Saúde , Cidade de Nova Iorque/epidemiologia , Prática de Saúde PúblicaRESUMO
Excess of reactive oxygen species (ROS) on in vitro embryo production systems negatively affects the quality and developmental potential of embryos, as result of a decreased sperm quality and increased DNA fragmentation. This issue is of major importance in assisted fertilisation procedures such as intracytoplasmic sperm injection (ICSI), because this technique does not allow the natural selection of competent spermatozoa, and therefore, DNA-damaged spermatozoa might be used to fertilise an egg. The aim of this study was to investigate a new strategy to prevent the potential deleterious effect of ROS on cryopreserved bovine spermatozoa. We evaluated the effect of a sperm pre-treatment with different concentrations of N-acetyl-L-cysteine (NAC) on ROS production, viability and DNA fragmentation and assessed the effect of this treatment on the in vitro developmental potential and quality of embryos generated by ICSI. The results show a strong scavenging effect of 1 and 10 mm NAC after exposure of spermatozoa to a ROS inducer, without compromising the viability and DNA integrity. Importantly, in vitro developmental potential and quality of embryos generated by ICSI with spermatozoa treated with NAC were not affected, confirming the feasibility of using this treatment before an ICSI cycle.
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Acetilcisteína/farmacologia , Criopreservação/métodos , Crioprotetores/farmacologia , Espécies Reativas de Oxigênio/efeitos adversos , Preservação do Sêmen/métodos , Injeções de Esperma Intracitoplásmicas/métodos , Espermatozoides/efeitos dos fármacos , Animais , Bovinos , Fragmentação do DNA , Desenvolvimento Embrionário/efeitos dos fármacos , Fertilização in vitro , Masculino , Espermatozoides/metabolismoRESUMO
Novel ß-lapachone analogs 2-phenyl-3,4-dihydro-2H-benzo[h]chromene-5,6-dione (NQ1), 2-p-tolyl-3,4-dihydro-2H-benzo[h]chromene-5,6-dione (NQ3) and 2-methyl-2-phenyl-3,4-dihydro-2H-benzo[h]chromene-5,6-dione (NQ7), which have trypanocidal activity, were assayed for cytotoxic effects on murine EL-4 T lymphoma cells. The NQs inhibited the proliferation of EL-4 cells at concentrations above 1µM. Nuclear staining of the EL-4 cells revealed chromatin condensation and a nuclear morphology compatible with the induction of apoptosis. Flow cytometry assays with annexin V-FITC and propidium iodide confirmed the cell death by apoptosis. Using electron paramagnetic resonance (EPR), a semiquinone radical was detected in EL-4 cells treated with NQs. In addition, a decrease in the GSH level in parallel with reactive oxygen species (ROS) production was observed. Preincubation with n-acetyl-l-cysteine (NAC) was able to reverse the inhibitory effects of the NQs on cell proliferation, indicating that ROS generation is involved in NQ-induced apoptosis. In addition, the NQs induced a decrease in the mitochondrial membrane potential and increased the proteolytic activation of caspases 9 and 3 and the cleavage of Poly (ADP-Ribose) Polymerase (PARP). In conclusion, these results indicate that redox cycling is induced by the NQs in the EL-4 cell line, with the generation of ROS and other free radicals that could inhibit cellular proliferation as a result of the induction of the intrinsic apoptosis pathway.