The combined treatment of gold nanoparticles associated with photobiomodulation accelerate the healing of dermonecrotic lesion

Introduction: The search for fast and efficient treatment for dermonecrotic lesions caused by the venom of the spider from the Loxosceles simillis, is a demand in health. Prednisolone is one of the most used drugs, however it has side effects. In this context, addictionally gold nanoparticles (GNPs) have anti-inflammatory, antioxidant, and antibacterial properties. The use of photobiomodulation has show to be efficient in the process of tissue repair. Therefore, the purpose of this study was to investigate the anti-inflammatory effect of photobiomodulation and GNPs associated or not with a low concentration of prednisolone in animal models of dermonecrotic lesion.Methodology: For this, rabbits with venon-induced dermonecrotic lesion were subjected to topical treatment with prednisolone + laser or GNPs + laser or Pred-GNPs + laser. The area of edema, necrosis and erythema were measured. On the last day of treatment, the animals were euthanized to remove the organs for histopathological and biochemical analysis.Results: All treatments combinations were effective in promoting the reduction of necrotic tissue and erythema.Conclusion: With this results, we suggest that the use of laser and nanoparticles, associated or not with prednisolone, should be considered for the treatment of dermonecrotic injury.

The involvement of neuroinflammation in an animal model of dementia and depression

Alzheimer's disease (AD) and depression are inflammatory pathologies, leading to increased inflammatory response and neurotoxicity. Therefore, this study aimed to evaluate the effect of the treatment with fluoxetine and/or galantamine and/or donepezil on the levels of proinflammatory and anti-inflammatory cytokines in a mixed animal model of depression and dementia. Adult male Wistar rats underwent chronic mild stress (CMS) protocol for 40 days and were subjected to stereotaxic surgery for intra-hippocampal administration of amyloid-beta (Aꞵ) peptide or artificial cerebrospinal fluid (ACSF) to mimic the dementia animal model. On the 42nd day, animals were treated with water, galantamine, donepezil, and/or fluoxetine, orally for 17 days. On the 57th and 58th days, the Splash and Y-maze tests for behavior analysis were performed. The frontal cortex and hippocampus were used to analyze the tumor necrosis factor alfa (TNF-α), interleukin 1 beta (IL-1ꞵ), IL-6, and IL-10 levels. The results of this study show that animals subjected to CMS and administration of Aꞵ had anhedonia, cognitive impairment, increased TNF-α and IL-1ꞵ levels in the frontal cortex, and reduced IL-10 levels in the hippocampus. All treatment groups were able to reverse the cognitive impairment. Only donepezil did not decrease the TNF-α levels in the hippocampus. Fluoxetine + galantamine and fluoxetine + donepezil reversed the anhedonia. Fluoxetine reversed the anhedonia and IL-1ꞵ levels in the frontal cortex. In addition, fluoxetine + donepezil reversed the reduction of IL-10 levels in the hippocampus. The results indicate a pathophysiological interaction between AD and depression, and the association of medications in the future may be a possible therapeutic strategy to reduce inflammation, especially the fluoxetine-associated treatments.

Role of Oxidative Stress on Insulin Resistance in Diet-Induced Obesity Mice

Insulin resistance is the link between obesity and type 2 diabetes mellitus. The molecular mechanism by which obese individuals develop insulin resistance has not yet been fully elucidated; however, inconclusive and contradictory studies have shown that oxidative stress may be involved in the process. Thus, this study aimed to evaluate the effect of reactive species on the mechanism of insulin resistance in diet-induced obese mice. Obese insulin-resistant mice were treated with N-acetylcysteine (NAC; 50 mg/kg per day, for 15 days) by means of oral gavage. Twenty-four hours after the last NAC administration, the animals were euthanized and their tissues were extracted for biochemical and molecular analyses. NAC supplementation induced improved insulin resistance and fasting glycemia, without modifications in food intake, body weight, and adiposity. Obese mice showed increased dichlorofluorescein (DCF) oxidation, reduced catalase (CAT) activity, and reduced glutathione levels (GSH). However, treatment with NAC increased GSH and CAT activity and reduced DCF oxidation. The gastrocnemius muscle of obese mice showed an increase in nuclear factor kappa B (NFκB) and protein tyrosine phosphatase (PTP1B) levels, as well as c-Jun N-terminal kinase (JNK) phosphorylation compared to the control group; however, NAC treatment reversed these changes. Considering the molecules involved in insulin signaling, there was a reduction in insulin receptor substrate (IRS) and protein kinase B (Akt) phosphorylation. However, NAC administration increased IRS and Akt phosphorylation and IRS/PI3k (phosphoinositide 3-kinase) association. The results demonstrated that oxidative stress-associated obesity could be a mechanism involved in insulin resistance, at least in this animal model.

The effectiveness of treadmill and swimming exercise in an animal model of osteoarthritis

Introduction: Osteoarthritis (OA) is considered an inflammatory and degenerative joint disease, characterized by loss of hyaline joint cartilage and adjacent bone remodeling with the formation of osteophytes, accompanied by various degrees of functional limitation and reduction in the quality of life of individuals. The objective of this work was to investigate the effects of treatment with physical exercise on the treadmill and swimming in an animal model of osteoarthritis. Methods: Forty-eight male Wistar rats were divided (n=12 per group): Sham (S); Osteoarthritis (OA); Osteoarthritis + Treadmill (OA + T); Osteoarthritis + Swimming (OA + S). The mechanical model of OA was induced by median meniscectomy. Thirty days later, the animals started the physical exercise protocols. Both protocols were performed at moderate intensity. Forty-eight hours after the end of the exercise protocols, all animals were anesthetized and euthanized for histological, molecular, and biochemical parameters analysis. Results: Physical exercise performed on a treadmill was more effective in attenuating the action of pro-inflammatory cytokines (IFN-γ, TNF-α, IL1-β, and IL6) and positively regulating anti-inflammatories such as IL4, IL10, and TGF-β in relation to other groups. Discussion: In addition to maintaining a more balanced oxi-reductive environment within the joint, treadmill exercise provided a more satisfactory morphological outcome regarding the number of chondrocytes in the histological evaluation. As an outcome, better results were found in groups submitted to exercise, mostly treadmill exercise.

Behavioral, genetic and biochemical changes in the brain of the offspring of female mice treated with caffeine during pregnancy and lactation

The intrauterine environment is a critical location for exposure to exogenous and endogenous factors that trigger metabolic changes through fetal programming. Among the external factors, chemical compounds stand out, which include caffeine, since its consumption is common among women, including during pregnancy. Thereby, the aim of the present study was to evaluate the behavioral, genetic, and biochemical parameters in the offspring of female mice treated with caffeine during pregnancy and lactation. Swiss female mice (60 days old) received tap water or caffeine at 0.3 or 1.0 mg/mL during copulation (7 days), pregnancy (21 days) and lactation (21 days). After the end of the lactation period, the offspring were divided into groups (water, caffeine 0.3 or 1.0 mg/mL) with 20 animals (10 animals aged 30 days and 10 animals aged 60 days per group per sex). Initially, the offspring were submitted to behavioral tasks and then euthanized for genetic and biochemical analysis in the brain (cortex, striatum, and hippocampus). Behavioral changes in memory, depression, and anxiety were observed in the offspring: 30-day-old female offspring at 1.0 mg /mL dose presented anxiogenic behavior and male offspring the 0.3 mg/mL dose at 30 days of age did not alter long-term memory. Furthermore, an increase in DNA damage and oxidative stress in the brain were observed in the offspring of both sexes. Furthermore, there were changes in Ape-1, BAX, and Bcl-2 in the female offspring hippocampus at 30 days of life. Thus, with this study, we can suggest genotoxicity, oxidative stress, and behavioral changes caused by caffeine during pregnancy and lactation in the offspring that were not treated directly, but received through their mothers; thus, it is important to raise awareness regarding caffeine consumption among pregnant and lactating females.

Effects of the intranasal application of gold nanoparticles on the pulmonary tissue after acute exposure to industrial cigarette smoke

Inhalation of harmful particles appears as a primary factor for the onset and establishment of chronic obstructive pulmonary disease (COPD). Cigarette smoke acutely promotes an exacerbated inflammatory response with oxidative stress induction with DNA damage. Administration of Gold Nanoparticles (GNPs) with 20 nm in different concentrations can revert damages caused by external aggravations. The effects of GNPs in a COPD process have not been observed until now. The objective of this work was to evaluate the therapeutic effects of intranasal administration of different doses of GNPs after acute exposure to industrial cigarette smoke. Thirty male Swiss mice were randomly divided into five groups: Sham; cigarette smoke (CS); CS + GNPs 2.5 mg/L; CS + GNPs 7.5 mg/L and CS + GNPs 22.5 mg/L. The animals were exposed to the commercial cigarette with filter in an acrylic inhalation chamber and treated with intranasal GNPs for five consecutive days. The results demonstrate that exposure to CS causes an increase in inflammatory cytokines, histological changes, oxidative and nitrosive damage in the lung, as well as increased damage to the DNA of liver cells, blood plasma and lung. Among the three doses of GNPs (2.5, 7.5, and 22.5 mg/L) used, the highest dose had better anti-inflammatory effects. However, GNPs at a dose of 7.5 mg/L showed better efficacies in reducing ROS formation, alveolar diameter, and the number of inflammatory cells in histology, in addition to significantly reduced rate of DNA damage in lung cells without additional systemic genotoxicity already caused by cigarette smoke.

Intra-articular treatment with hyaluronic acid associated with gold nanoparticles in a mechanical osteoarthritis model in Wistar rats

This study aimed to evaluate the effects of intra-articular treatment with hyaluronic acid (HA) associated with GNPs in a mechanical model of osteoarthritis induced by median meniscectomy (MM). Fifty Wistar rats (2 months weighing between 250 and 300 g) were used, divided into five groups of 10 animals each: Sham, osteoarthritis (OA), OA + HA, OA + gold nanoparticles (GNPs), and OA + HA + GNPs. Intra-articular treatment was started 30 days after the model was induced, with a frequency of 2 weeks for 60 days. Fifteen days after the last application, the animals were euthanized with the removal of the joint tissue for biochemical and histological analysis. The model used was able to mimic osteoarthritis, characterized by the presence of high levels of proinflammatory cytokines, oxidative stress, and degeneration of joint surfaces (Grade III, according to SCORE OARSI). The isolated use of HA or GNPs provided beneficial results to the joint; however, only the group subjected to the association between HA and GNPs showed the attenuation of oxidative stress and reduced proinflammatory markers, with a simultaneous increase in levels of anti-inflammatory cytokines and growth factors. Upon histological analysis, only the OA + HA + GNPs group achieved the restoration of the thickness of the joint cartilage with reduced damage and return to the intact joint surface. The results found demonstrated that the association of GNPs with HA was able to reverse the deleterious effects caused by the model by inhibiting the progressive degeneration of joint surfaces, representing a promising treatment for osteoarthritis.

Effects of cryotherapy on the regeneration process and muscular mechanical properties after lacerative injury model

Cryotherapy is a therapeutic modality widely used for the treatment of muscle injuries to control pain and inflammatory processes. This study aimed to investigate the effects of cryotherapy on the inflammatory and oxidative stress parameters and mechanical properties of, and pain in, the skeletal muscles of rats with lacerative muscle injury. The rats were anesthetized with 4% isoflurane and subjected to gastrocnemius muscle laceration injury. After injury, all animals in the intervention groups received cryotherapy treatment for 20 minutes using plastic bags containing crushed ice. The protocol comprised three daily applications at 3-hour intervals on the day of injury, with reapplication 24 hours later. Seventy-two male Wistar rats were divided into three groups: sham, muscle injury (MI), and MI + cryotherapy (MI + cryo). Muscle mechanical properties were analyzed by mechanical tensile testing on day 7 after injury. The MI + cryo group showed reduced TNF-α, IFN-γ, and IL1β levels; elevated IL4, IL6, and IL10 levels; reduced oxidant production and carbonyl levels; and elevated sulfhydryl contents. Animals that underwent tissue cooling showed superoxide dismutase activity and glutathione levels close to those of the animals in the sham group. The MI and MI + cryo groups showed reduced values of the evaluated mechanical properties and lower mechanical thresholds compared to those of the animals from the sham group. Our results demonstrated that the proposed cryotherapy protocol reduced the inflammatory process and controlled oxidative stress but did not reverse the changes in the mechanical properties of muscle tissues or provide analgesic effects within the time frame analyzed.

Cotreatment of Small Gold Nanoparticles Protects Against the Increase in Cerebral Acetylcholinesterase Activity and Oxidative Stress Induced by Acute Ethanol Exposure in the Zebrafish

Gold nanoparticles (GNP) have emerged as an alternative to biomaterials in biomedical applications. Research has clearly demonstrated the relative safety and low toxicity of these molecules. However, the possible neuroprotective effect of GNP on the central nervous system (CNS) and its relationship with neurological and psychiatric disorders remain unclear. Zebrafish is a reliable model to investigate the impact of ethanol (EtOH) consumption on the CNS, including reward signaling such as the cholinergic neurotransmission system. Here, we investigated whether cotreatment or pretreatment with GNP prevented EtOH-induced changes in acetylcholinesterase activity and oxidative stress in the brain of zebrafish. We exposed adult zebrafish to 2.5 mg·L^-1 GNP 1 h prior to EtOH (1% v/v) treatment for 1 h, and cotreated adult zebrafish simultaneously with both substances for 1 h. Pretreatment with GNP did not prevent EtOH-induced increase in the acetylcholinesterase activity, whereas cotreatment with 2.5 mg·L^-1 GNP and EtOH protected against this increase. The results also suggested similar protective effect on oxidative stress parameters in the zebrafish pretreated with GNP at 2.5 mg·L^-1. GNP significantly decreased the levels of thiobarbituric acid reactive species and dihydrodichlorofluorescein levels when cotreated with EtOH. GNP also prevented EtOH-induced increase in superoxide dismutase and catalase activities, suggesting a modulatory role of GNP in enzymatic antioxidant defenses. Our results showed that GNP was able to modulate the disruption of cholinergic and oxidative homeostasis in the brain of zebrafish. These findings indicate for the first time that zebrafish is an interesting perspective to investigate nanoparticles against disorders related to alcohol abuse.

Effects of the Association between Photobiomodulation and Hyaluronic Acid Linked Gold Nanoparticles in Wound Healing

Healing is the process responsible for restoring the integrity of the body's internal or external structures when they rupture. Photobiomodulation (PBM) stands out as one of the most efficient resources in the treatment of epithelial lesions, as well as hyaluronic acid (HA), which has been emerging as a new molecule for the treatment of dermal and epidermal lesions. The biological application of gold nanoparticles (GNPs) shows promising results. This study aimed to investigate the possible anti-inflammatory and antioxidant effects of the association between PBM and GNPs-linked HA in an epithelial lesion model. Fifty Wistar rats were randomly distributed in the Control Group (CG); (PBM); (PBM + HA); (PBM + GNPs); (PBM + GNPs-HA). The animals were anesthetized, trichotomized, and induced to a surgical incision in the dorsal region. Topical treatment with HA (0.9%) and/or GNPs (30 mg/kg) occurred daily associated with 904 nm laser irradiation, dose of 5 J/cm², which started 24 h after the lesion and was performed daily until the seventh day. The levels of proinflammatory (IL1 and TNFα), anti-inflammatory (IL10 and IL4) and growth factors (FGF and TGFβ) cytokines and oxidative stress parameters were evaluated, besides histological analysis through inflammatory infiltrate, fibroblasts, new vessels, and collagen production area. Finally, for the analysis of wound size reduction, digital images were performed and subsequently analyzed by the IMAGEJ software. The treated groups showed a decrease in proinflammatory cytokine levels and an increase in anti-inflammatory cytokines. TGFβ and FGF levels also increased in the treated groups, especially in the combination therapy group (PBM + GNPs-HA). Regarding the oxidative stress parameters, MPO, DCF, and Nitrite levels decreased in the treated groups, as well as the oxidative damage (Carbonyl and Thiol groups). In contrast, antioxidant defense increased in the groups with the appropriate therapies proposed compared to the control group. Histological sections were analyzed where the inflammatory infiltrate was lower in the PBM + GNPs-HA group. The number of fibroblasts was higher in the PBM and PBM + HA treated groups, whereas collagen production was higher in all treated groups. Finally, in the analysis of the wound area contraction, the injury group presented a larger area in cm² compared to the other groups. Taken together, these results allow us to observe that the combination of PBM + GNPs-HA optimized the secretion of anti-inflammatory cytokines, proliferation and cell differentiation growth factors, and made an earlier transition to the chronic phase, contributing to the repair process.

Macrophages and Schwann cell TRPA1 mediate chronic allodynia in a mouse model of complex regional pain syndrome type I

Complex regional pain syndrome type I (CRPS-I) is characterized by intractable chronic pain. Poor understanding of the underlying mechanisms of CRPS-I accounts for the current unsatisfactory treatment. Antioxidants and antagonists of the oxidative stress-sensitive channel, the transient receptor potential ankyrin 1 (TRPA1), have been found to attenuate acute nociception and delayed allodynia in models of CRPS-I, evoked by ischemia and reperfusion (I/R) of rodent hind limb (chronic post ischemia pain, CPIP). However, it is unknown how I/R may lead to chronic pain mediated by TRPA1. Here, we report that the prolonged (day 1-15) mechanical and cold allodynia in the hind limb of CPIP mice was attenuated permanently in Trpa1^-/- mice and transiently after administration of TRPA1 antagonists (A-967079 and HC-030031) or an antioxidant (α-lipoic acid). Indomethacin treatment was, however, ineffective. We also found that I/R increased macrophage (F4/80⁺ cell) number and oxidative stress markers, including 4-hydroxynonenal (4-HNE), in the injured tibial nerve. Macrophage-deleted MaFIA (Macrophage Fas-Induced Apoptosis) mice did not show I/R-evoked endoneurial cell infiltration, increased 4-HNE and mechanical and cold allodynia. Furthermore, Trpa1^-/- mice did not show any increase in macrophage number and 4-HNE in the injured nerve trunk. Notably, in mice with selective deletion of Schwann cell TRPA1 (Plp1-Cre^ERT;Trpa1^fl/fl mice), increases in macrophage infiltration, 4-HNE and mechanical and cold allodynia were attenuated. In the present mouse model of CRPS-I, we propose that the initial oxidative stress burst that follows reperfusion activates a feed forward mechanism that entails resident macrophages and Schwann cell TRPA1 of the injured tibial nerve to sustain chronic neuroinflammation and allodynia. Repeated treatment one hour before and for 3 days after I/R with a TRPA1 antagonist permanently protected CPIP mice against neuroinflammation and allodynia, indicating possible novel therapeutic strategies for CRPS-I.

Reduction of oxidative stress improves insulin signaling in cardiac tissue of obese mice

Objective

To evaluate the effects of oxidative stress on insulin signaling in cardiac tissue of obese mice.

Methods

Thirty Swiss mice were equally divided (n=10) into three groups: Control Group, Obese Group, and Obese Group Treated with N-acetylcysteine. After obesity and insulin resistance were established, the obese mice were treated with N-acetylcysteine at a dose of 50mg/kg daily for 15 days via oral gavage.

Results

Higher blood glucose levels and nitrite and carbonyl contents, and lower protein levels of glutathione peroxidase and phosphorylated protein kinase B were observed in the obese group when compared with their respective control. On the other hand, treatment with N-acetylcysteine was effective in reducing blood glucose levels and nitrite and carbonyl contents, and significantly increased protein levels of glutathione peroxidase and phosphorylated protein kinase B compared to the Obese Group.

Conclusion

Obesity and/or a high-lipid diet may result in oxidative stress and insulin resistance in the heart tissue of obese mice, and the use of N-acetylcysteine as a methodological and therapeutic strategy suggested there is a relation between them.

Cigarette smoke exposure induces ROS-mediated autophagy by regulating sestrin, AMPK, and mTOR level in mice

Many pathological conditions linked to cigarette smoking are caused by the production of reactive oxygen species (ROS). The present study was conducted to analyze the effect of ROS on the lungs of Swiss mice exposed to cigarette smoking, focusing on autophagy-mediated mechanisms, and investigate the involvement of SESN2, AMPK, and mTOR signaling. Mice were exposed to cigarette smoke (CS) for 7, 15, 30, 45, and 60 days; the control group was not exposed to CS. Only mice exposed to CS for 45 days were selected for subsequent N-acetylcysteine (NAC) supplementation and smoke cessation analyses. Exposure to CS increased the production of ROS and induced molecular changes in the autophagy pathway, including an increase in phosphorylated AMPK and ULK1, reduction in phosphorylated mTOR, and increases in SESN2, ATG12, and LC3B levels. NAC supplementation reduced ROS levels and reversed all molecular changes observed upon CS treatment, suggesting the involvement of oxidative stress in inducing autophagy upon CS exposure. When exposure to CS was stopped, there were decreases in the levels of oxidative stress, AMPK and ULK1 phosphorylation, and autophagy-initiating molecules and increase in mTOR phosphorylation. In conclusion, these results suggest the involvement of ROS, SESN2, AMPK, and mTOR in the CS-induced autophagic process in the lung.

Effects of phonophoresis with diclofenac linked gold nanoparticles in model of traumatic muscle injury

The use of nanotechnology for administering drugs is a recent development that presents promising results. Therapeutic Pulsed Ultrasound (TPU) is one such therapeutic option and is widely used for treating soft tissue lesions. Thus, the objective of this study was to investigate the therapeutic effect of phonophoresis using diclofenac (DC) linked to gold nanoparticles (GNPs) in the skeletal muscle of rats used as a model of traumatic muscular injury. Wistar rats were divided into eight groups (N = 10): Sham, Muscle injury (MI), MI + TPU, MI + DC, MI + GNPs, MI + TPU + DC, MI + TPU + GNPs, and MI + TPU + DC-GNPs. The traumatic injury was performed in the gastrocnemius with a single direct traumatic impact via an injuring press. The animals received daily treatment for 5 consecutive days with TPU and gel with DC and/or GNPs. Two hours after the last treatment session, animals were euthanized and the gastrocnemius muscle surgically removed for histological and biochemical analysis. The groups exposed to some therapies (MI + TPU + DC, MI + TPU + GNPs and MI + TPU + DC-GNPs) showed reduced levels of pro-inflammatory cytokines, whereas an increase in anti-inflammatory cytokine levels was observed in the group exposed to all therapies combined (MI + TPU + DC-GNPs). Reactive species production and protein damage resulting from oxidative damage was lower for the group exposed to all tested therapies had lower production. Lower protein damage was also observed in the TPU + GNPs group. The group that underwent all tested therapies combined showed a significant increase in antioxidants compared to the MI group. During histological analysis, the MI group showed large amounts of cell infiltration and centralized nuclei, whereas the MI + TPU + DC-GNPs group showed structural improvements. Pain levels in the MI + TPU + DC-GNPs group were lower than those of the MI group. We believe that the association of TPU with DC linked to GNPs decreases the inflammation caused by traumatic muscle injury and accelerates tissue repair.

Effects of treatment with gold nanoparticles in a model of acute pulmonary inflammation induced by lipopolysaccharide

The bacterial lipopolysaccharide (LPS) is a highly toxic molecule derived from the outer membrane of gram-negative bacteria. LPS endotoxin affects the lungs and is used as a model of acute pulmonary inflammation affecting the cellular morphology of the organ. Previously, gold nanoparticles (GNPs) have been shown to demonstrate anti-inflammatory and antioxidative activity in muscle and epithelial injury models. The objective of this study was to investigate the effect of the intraperitoneal treatment using GNPs on the inflammatory response and pulmonary oxidative stress induced by LPS. Wistar rats were divided into four groups (N = 10): Sham; Sham + GNPs 2.5 mg/kg; LPS; and LPS + GNPs 2.5 mg/kg. Treatment with LPS upregulated the levels of markers of cellular and hepatic damage (CK, LDH, AST, and alanine aminotransferase); however, the group treated with only GNPs exhibited no toxicity. Treatment with GNPs reversed LPS-induced changes with respect to total peritoneal leukocyte count and the pulmonary levels of pro-inflammatory cytokines (IFN-γ and IL-6). Histological analysis revealed that treatment with GNPs reversed the increase in alveolar septum thickness due to LPS-induced fibrosis. In addition, treatment with GNPs decreased production of oxidants (nitrite and DCFH), reduced oxidative damage (carbonyl and sulfhydryl), and downregulated activities of superoxide dismutase and catalase. Treatment with GNPs did not showed toxicity; however, it exhibited anti-inflammatory and antioxidative activity that reversed morphological alterations induced by LPS.

Diet-induced obesity causes hypothalamic neurochemistry alterations in Swiss mice

The aim of this study was to assess inflammatory parameters, oxidative stress and energy metabolism in the hypothalamus of diet-induced obese mice. Male Swiss mice were divided into two study groups: control group and obese group. The animals in the control group were fed a diet with adequate amounts of macronutrients (normal-lipid diet), whereas the animals in the obese group were fed a high-fat diet to induce obesity. Obesity induction lasted 10 weeks, at the end of this period the disease model was validated in animals. The animals in the obese group had higher calorie consumption, higher body weight and higher weight of mesenteric fat compared to control group. Obesity showed an increase in levels of interleukin 1β and decreased levels of interleukin 10 in the hypothalamus. Furthermore, increased lipid peroxidation and protein carbonylation, and decreased level of glutathione in the hypothalamus of obese animals. However, there was no statistically significant difference in the activity of antioxidant enzymes, superoxide dismutase and catalase. The obese group had lower activity of complex I, II and IV of the mitochondrial respiratory chain, as well as lower activity of creatine kinase in the hypothalamus as compared to the control group. Thus, the results from this study showed changes in inflammatory markers, and dysregulation of metabolic enzymes in the pathophysiology of obesity.

Effects of aquatic exercise on mental health, functional autonomy and oxidative stress in depressed elderly individuals: A randomized clinical trial

OBJECTIVES

The aim of this study was to investigate the effects of aquatic exercise on mental health, functional autonomy and oxidative stress parameters in depressed elderly individuals.

METHODS

Initially, ninety-two elderly individuals were included in the study and were allocated into the depression group (n=16) and nondepression group (n=14). Both groups engaged in the aquatic exercise program for 12 weeks, including two weekly sessions (45 min/session) at a low intensity (between 50% and 60% of maximal heart rate or Borg scale scores of 13 to 14) throughout the intervention. All outcomes were evaluated at baseline and 12 weeks later.

RESULTS

The patients were 63.5±8.8 years old. The following scores were decreased after training in the depressed group: depression (53%), anxiety (48%), and Timed Up & Go (33%). The following scores increased: Berg Balance Scale (9%) and flexibility (44%). Regarding the blood-based parameters, there were decreases in protein carbonylation (46%) and nitric oxide (60%) and increases in glutathione (170%) and superoxide dismutase (160%) in the depression group (p<0.005).

CONCLUSIONS

The aquatic exercise program reduces depression and anxiety, improves functional autonomy and decreases oxidative stress in depressed elderly individuals.

Safety protocol for the gold nanoparticles administration in rats

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.

Gold nanoparticles prevent cognitive deficits, oxidative stress and inflammation in a rat model of sporadic dementia of Alzheimer's type

Alzheimer's disease (AD) is the most common form of neurodegenerative dementia in the aged brain. Even though its etiology is unknown, factors such as neuroinflammation, mitochondrial dysfunction, formation of reactive oxygen species (ROS), and impaired insulin signaling may play a role. We used a sporadic AD model in rats generated by intracerebroventricular-streptozotocin (i.c.v.-STZ) injection to test the therapeutic effect of gold nanoparticles (GNPs). We tested the null hypothesis that there would be no difference between the STZ+GNPs group and the STZ group in the analyzed markers. We observed that STZ-induced impairment in mitochondrial ATP production, neuroinflammation, and oxidative stress were all prevented by GNP treatment. Moreover, while STZ induced deficits in both spatial and recognition memory, GNPs prevented this effect. These results suggest that GNPs may be considered as a potential treatment for dementias.