Gold nanoparticles alter parameters of oxidative stress and energy metabolism in organs of adult rats.

This study evaluated the parameters of oxidative stress and energy metabolism after the acute and long-term administration of gold nanoparticles (GNPs, 10 and 30 nm in diameter) in different organs of rats. Adult male Wistar rats received a single intraperitoneal injection or repeated injections (once daily for 28 days) of saline solution, GNPs-10 or GNPs-30. Twenty-four hours after the last administration, the animals were killed, and the liver, kidney, and heart were isolated for biochemical analysis. We demonstrated that acute administration of GNPs-30 increased the TBARS levels, and that GNPs-10 increased the carbonyl protein levels. The long-term administration of GNPs-10 increased the TBARS levels, and the carbonyl protein levels were increased by GNPs-30. Acute administration of GNPs-10 and GNPs-30 increased SOD activity. Long-term administration of GNPs-30 increased SOD activity. Acute administration of GNPs-10 decreased the activity of CAT, whereas long-term administration of GNP-10 and GNP-30 altered CAT activity randomly. Our results also demonstrated that acute GNPs-30 administration decreased energy metabolism, especially in the liver and heart. Long-term GNPs-10 administration increased energy metabolism in the liver and decreased energy metabolism in the kidney and heart, whereas long-term GNPs-30 administration increased energy metabolism in the heart. The results of our study are consistent with other studies conducted in our research group and reinforce the fact that GNPs can lead to oxidative damage, which is responsible for DNA damage and alterations in energy metabolism.

Sodium butyrate decreases the activation of NF-κB reducing inflammation and oxidative damage in the kidney of rats subjected to contrast-induced nephropathy.

BACKGROUND: Contrast-induced nephropathy (CIN) is associated with a combination of hypoxic and toxic renal tubular damage, renal endothelial dysfunction and altered intra-renal microcirculation. Recently, sodium butyrate (SB) has been focused on since it possesses anti-inflammatory activities. Thus, based on the lack of information on the effects of SB in acute kidney injury (AKI), we investigated the possible effects of SB after CIN in rats. METHODS: Wistar rats were divided into three groups: (1 sham) control, (2 MI) AKI treated with contrast medium and (3 MI + SB) AKI plus SB. Six days after contrast administration, blood and kidney were removed for the determination of creatinine, interleukin (IL)-6 levels, oxidative damage parameters and histologic analyses. Nuclear factor kappa B (NF-κB), pIκBα and vasodilator-stimulated phosphoprotein (VASP) protein content were determined by immunoblotting. RESULTS: After 6 days, the levels of creatinine increased significantly in the MI group, and this was attenuated using SB. SB treatment was associated with a decrease on the levels of lipid peroxidation, but not the protein oxidation, and IL-6 levels, as well as tubular damage. These effects are probably mediated, in part, by a decrease on the activation of NF-κB in the kidney, but not alteration in pVASP content. CONCLUSIONS: The current experiment suggests that NF-κB induced an inflammatory response after CIN and SB could inhibit NF-κB expression protecting against CIN in rats.

Effect of acute and long-term administration of gold nanoparticles on biochemical parameters in rat brain.

The present study investigated stress oxidative parameters and activities of enzymes of the energy metabolism in various brain structures. Rats were subjected to acute and long-term administration of gold nanoparticles (GNPs) with mean diameters of 10nm and 30nm. Adult (60days old) male Wistar rats received a single intraperitoneal injection (acute administration; 70µg·kg-1) or repeated injections once daily for 28days (long-term administration; 70µg·kg-1) of saline solution or GNPs (10nm or 30nm). Twenty-four hours after administration of the final dose, the animals were killed and the cerebral structures were isolated for enzyme analysis. In this study, we observed that the thiobarbituric acid-reactive species and carbonyl protein levels were decreased after acute administration of GNPs, whereas the superoxide dismutase activity was increased after acute and long-term of GNPs. The catalase activity was affected by the administration of GNPs. Furthermore, we have not found change in the citrate synthase activity. The succinate dehydrogenase, malate dehydrogenase, complexes I, II, II-III and IV, and creatine kinase activities were altered. These results indicate that inhibition energy metabolism can be caused by oxidative stress.

Effect of red blood cell transfusion on parameters of inflammation and oxidative stress in critically ill patients. / Efeito da transfusão de concentrado de hemácias sobre parâmetros de inflamação e estresse oxidativo em pacientes criticamente enfermos.

INTRODUCTION: Red blood cell transfusions are common in intensive care units. For many years, transfusions of red blood were thought to have obvious clinical benefits. However, in recent years, the risks and benefits of blood transfusions have been examined more carefully, including the risk of increased morbidity and mortality due to transfusion-related immunomodulation effects. OBJECTIVES: To evaluate red blood cell transfusion effects and the relationship of this procedure to the production of inflammatory cytokines and oxidative damage in critically ill patients admitted to an intensive care unit. METHODS: For 6 months in 2008, we evaluated patients admitted to an intensive care unit who underwent packed red blood cell transfusions. Pre- and post-transfusion levels of interleukin-6, carbonylated proteins and thiobarbituric acid reactive substances were assessed. RESULTS: Serum post-transfusion interleukin-6 levels were reduced, and thiobarbituric acid reactive substances and carbonylated proteins were significantly increased. No statistically significant relationship was found between the levels of pre- and post-transfusion interleukin-6 and thiobarbituric acid reactive substances and the mortality rate. However, there was a significant relationship between levels of post-transfusion carbonylated proteins and mortality. CONCLUSION: Red blood cell transfusion is associated with increased oxidative damage markers and reduced interleukin-6 levels in critically ill patients.

Efeito da transfusão de concentrado de hemácias sobre parâmetros de inflamação e estresse oxidativo em pacientes criticamente enfermos / Effect of red blood cell transfusion on parameters of inflammation and oxidative stress in critically ill patients

INTRODUÇÃO: Transfusão de concentrado de hemácias é freqüentemente prescrita nas unidades de terapia intensiva. Durante muito tempo a transfusão de hemácias era vista como tendo benefícios clínicos óbvios. Entretanto nos últimos anos a prática de transfusão sanguínea tem sido examinada de uma forma mais cautelosa, levando a investigações a respeito dos benefícios transfusionais, incluindo aqui o fato de os efeitos imunomoduladores relacionados à transfusão podem aumentar o risco de morbimortalidade dos pacientes. OBJETIVOS: Avaliar o efeito da transfusão de concentrado de hemácias e sua relação com a produção de citocinas inflamatórias e dano oxidativo em pacientes criticamente enfermos admitidos em uma unidade de terapia intensiva. MÉTODOS: Foram analisados durante 6 meses, no ano de 2008, pacientes internados na unidade de terapia intenvia que realizaram transfusão de concentrado de hemácias. Foram analisados os níveis séricos pré e pós transfusionais de interleucina-6 (IL-6), proteínas carboniladas e substâncias reativas ao ácido tiobarbitúrico (TBARS). RESULTADOS: Houve diminuição dos níveis séricos de IL-6 pós-transfusionais e um aumento significativo tanto para TBARS quanto para proteínas carboniladas. No entanto não houve significância estatística entre os níveis séricos de IL-6, TBARS antes e após transfusão de concentrado de hemácias e a taxa de mortalidade. Contudo ocorreu significância da relação dos níveis pós transfusionais de proteínas carboniladas e mortalidade. CONCLUSÃO: Transfusão de concentrado de hemácias é associada a aumento dos marcadores de dano oxidativo e diminuição de IL-6 em pacientes criticamente enfermos.

INTRODUCTION: Red blood cell transfusions are common in intensive care units. For many years, transfusions of red blood were thought to have obvious clinical benefits. However, in recent years, the risks and benefits of blood transfusions have been examined more carefully, including the risk of increased morbidity and mortality due to transfusion-related immunomodulation effects. OBJECTIVES: To evaluate red blood cell transfusion effects and the relationship of this procedure to the production of inflammatory cytokines and oxidative damage in critically ill patients admitted to an intensive care unit. METHODS: For 6 months in 2008, we evaluated patients admitted to an intensive care unit who underwent packed red blood cell transfusions. Pre- and post-transfusion levels of interleukin-6, carbonylated proteins and thiobarbituric acid reactive substances were assessed. RESULTS: Serum post-transfusion interleukin-6 levels were reduced, and thiobarbituric acid reactive substances and carbonylated proteins were significantly increased. No statistically significant relationship was found between the levels of pre- and post-transfusion interleukin-6 and thiobarbituric acid reactive substances and the mortality rate. However, there was a significant relationship between levels of post-transfusion carbonylated proteins and mortality. CONCLUSION: Red blood cell transfusion is associated with increased oxidative damage markers and reduced interleukin-6 levels in critically ill patients.