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In this study, we performed two experiments. In the first experiment, the objective was to link gold nanoparticles (GNPs) with sodium diclofenac and/or soy lecithin and to determine their concentration in tissues and their toxicity using hepatic and renal analyzes in mice to evaluate their safety as therapeutic agents in the subsequent treatment of obesity. In the second experiment, we evaluated the effect of GNPs on inflammatory and biochemical parameters in obese mice. In the first experiment, we synthesized and characterized 18 nm GNPs that were administered intraperitoneally in isolation or in association with sodium diclofenac and/or soy lecithin in mice once daily for 1 or 14 days. Twenty-four hours after the single or final administration, the animals were euthanized, following which the tissues were removed for evaluating the concentration of GNPs, and serum samples were collected for hepatic and renal analysis. Hepatic damage was evaluated based on the levels of alanine aminotransferase (ALT), whereas renal damage was evaluated based on creatinine levels. A higher concentration of GNPs was detected in the tissues upon administration for 14 days, and there were no signs of hepatic or renal damage. In the second experiment, the mice were used as animal models of obesity and were fed a high-fat diet (obese group) and control diet (control group). After eight weeks of high-fat diet administration, the mice were treated with saline or with GNPs (average size of 18 nm) at a concentration of 70 mg/L (70 mg/kg) once a day, for 14 days, for 10 weeks. Body weight and food intake were measured frequently. After the experiment ended, the animals were euthanized, serum samples were collected for glucose and lipid profile analysis, the mesenteric fat content was weighed, and the brains were removed for inflammatory and biochemical analysis. In obese mice, although GNP administration did not reduce body and mesenteric fat weight, it reduced food intake. The glucose levels were reversed upon administration of GNPs, whereas the lipid profile was not altered in any of the groups. GNPs exerted a beneficial effect on inflammation and oxidative stress parameters, without reverting mitochondrial dysfunction. Our results indicate that the intraperitoneal administration of GNPs for 14 days results in a significant GNP concentration in adipose tissues, which could be an interesting finding for the treatment of inflammation associated with obesity. Based on the efficacy of GNPs in reducing dietary intake, inflammation, and oxidative stress, they can be considered potential alternative agents for the treatment of obesity., (Copyright © 2020 Elsevier B.V. All rights reserved.)

One of the important components in tissue engineering is material structure, providing a model for fixing and the development of cells and tissues, which allows for the transport of nutrients and regulatory molecules to and from cells. The community claims the need for new materials with better properties for use in the clinic. Poly (ε-caprolactone) (PCL) is a biodegradable polymer, semi crystalline, with superior mechanical properties and has attracted an increasing interest due to its usefulness in various biomedical applications. Herein, two different methods (electrospinning versus rotary jet spinning) with different concentrations of PCL produced ultra thin-fibers each with particular characteristics, verified and analyzed by morphology, wettability, thermal and cytotoxicity features and for bacteria colonization. Different PCL scaffold morphologies were found to be dependent on the fabrication method used. All PCL scaffolds showed greater mammalian cell interactions. Most impressively, rotary-jet spun fibers showed that a special rough surface decreased bacteria colonization, emphasizing that no nanoparticle or antibiotic was used; maybe this effect is related with physical (scaffold) and/or biological mechanisms. Thus, this study showed that rotary jet spun fibers possess a special topography compared to electrospun fibers to reduce bacteria colonization and present no cytotoxicity when in contact with mammalian cells., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

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., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Gold nanoparticles (GNPs) have antioxidant and anti-inflammatory effects. However, toxicity is still a concern; therefore, it is critical to study both the therapeutic and toxic properties of GNPs. In this study, we evaluated the effects of the intraperitoneal administration of GNPs (20nm, at a concentration of 2.5mg/L for 21days) every 24 or 48h on oxidative stress, antioxidant status, and electron chain transport (ETC) in the brain. Liver histology and blood marker analyses were conducted to establish a time routine of GNP administration. The concentrations of GNP in the brain and liver were similar. Hepatic and serum levels of cholesterol, triglycerides, and transaminases were not altered after the administration of GNP every 24 or 48h. The superoxide and nitric oxide levels were unchanged after administration of GNP. Dichlorodihydrofluorescein (DCFH) levels decreased after the administration of GNP every 48h compared with that in the saline group. Sulfhydryl and carbonyl levels, as well as superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and glutathione (GSH) activities were not altered in the brain after administration of GNP in the two time periods studied. The GNP 48h group showed increased brain ETC activity. Compared to that in the saline group, the GNP 24h group showed marked parenchyma changes with cell necrosis and leukocyte infiltration. We therefore suggest that a concentration of 2.5mg/L of GNP administered every 48h has potential therapeutic benefits without toxicity., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The aim of this study was to analyse the effects of microcurrent and gold nanoparticles on oxidative stress parameters and the mitochondrial respiratory chain in the healing of skin wounds. Thirty 60-day old male Wistar rats (250-300 g) were divided into five groups (N=6): Control; Burn wounds; Microcurrent (MIC); Gold nanoparticle gel (GNP gel) and Microcurrent+Gold nanoparticle gel (MIC+GNP gel). The microcurrent treatment was applied for five consecutive days at a dose of 300 μA. The results demonstrate a significant decrease in the activity of complexes I, II-III and IV in the Burn Wounds group compared to the control, and the MIC+GNP gel group was able to reverse this inhibition in complexes I, III and IV. Furthermore, a significant reduction in oxidative damage parameters and a significant increase in the levels of antioxidant defence enzymes were induced in the MIC+GNP gel group compared to the Burn Wounds group. The data strongly indicate that the group receiving treatment with MIC+GNP gel had improved mitochondrial functioning and oxidative stress parameters, which contributed to tissue repair., (Copyright © 2014 Elsevier B.V. All rights reserved.)