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Allergic asthma is characterized by chronic airway inflammation and is constantly associated with anxiety disorder. Recent studies showed bidirectional interaction between the brain and the lung tissue. However, where and how the brain is affected in allergic asthma remains unclear. We aimed to investigate the neuroinflammatory, neurochemical, and neurometabolic alterations that lead to anxiety-like behavior in an experimental model of allergic asthma. Mice were submitted to an allergic asthma model induced by ovalbumin (OVA) and the control group received only Dulbecco's phosphate-buffered saline (DPBS). Our findings indicate that airway inflammation increases interleukin (IL) -9, IL-13, eotaxin, and IL-1β release and changes acetylcholinesterase (AChE) and Na

Methylphenidate (MPH) has been widely misused by children and adolescents who do not meet all diagnostic criteria for attention-deficit/hyperactivity disorder without a consensus about the consequences. Here, we evaluate the effect of MPH treatment on glucose metabolism and metabolic network in the rat brain, as well as on performance in behavioral tests. Wistar male rats received intraperitoneal injections of MPH (2.0 mg/kg) or an equivalent volume of 0.9% saline solution (controls), once a day, from the 15th to the 44th day of age. Fluorodeoxyglucose-18 was used to investigate the cerebral metabolism, and a cross-correlation matrix was used to examine the brain metabolic network in MPH-treated rats using micro-positron emission tomography imaging. Performance in the light-dark transition box, eating-related depression, and sucrose preference tests were also evaluated. While MPH provoked glucose hypermetabolism in the auditory, parietal, retrosplenial, somatosensory, and visual cortices; hypometabolism was identified in the left orbitofrontal cortex. MPH-treated rats show a brain metabolic network more efficient and connected, but careful analyzes reveal that the MPH interrupts the connection of the orbitofrontal cortex with other brain areas. Anxiety-like behavior was also observed in MPH-treated rats. This study shows that glucose metabolism evaluated by microPET in the brain can be affected by MPH in different ways according to the region of the brain studied. It may be related, at least in part, to a rewiring in brain the metabolic network and behavioral changes observed, representing an important step in exploring the mechanisms and consequences of MPH treatment.

During chronic inflammatory disease, such asthma, leukocytes can invade the central nervous system (CNS) and together with CNS-resident cells, generate excessive reactive oxygen species (ROS) production as well as disbalance in the antioxidant system, causing oxidative stress, which contributes a large part to neuroinflammation. In this sense, the aim of this study is to investigate the effects of treatment with neostigmine, known for the ability to control lung inflammation, on oxidative stress in the cerebral cortex of asthmatic mice. Female BALB/cJ mice were submitted to asthma model induced by ovalbumin (OVA). Control group received only Dulbecco's phosphate-buffered saline (DPBS). To evaluate neostigmine effects, mice received 80 μg/kg of neostigmine intraperitoneally 30 min after each OVA challenge. Our results revealed for the first time that treatment with neostigmine (an acetylcholinesterase inhibitor that no crosses the BBB) was able to revert ROS production and change anti-oxidant enzyme catalase in the cerebral cortex in asthmatic mice. These results support the communication between the peripheral immune system and the CNS and suggest that acetylcholinesterase inhibitors, such as neostigmine, should be further studied as possible therapeutic strategies for neuroprotection in asthma.

Throughout gestation, proteins in the diet are a source of essential amino acids that are crucial for proper healthy fetal growth and development. The present study was proposed to investigate the effect of high-protein diet consumption throughout pregnancy on redox homeostasis, neuroinflammatory status and amino acid levels, including homocysteine, in the male adolescent rats offspring's cerebral cortex. We also performed a battery of behavioral tests to evaluate maternal care, olfactory preference, exploratory capacity, habituation, memory, anxiety- and depression-like behavior motor activity in the offspring.After pregnancy confirmation, the pregnant rats were randomly divided into two groups, according to the diet: group 1, (control) standard diet containing 20 % protein, and group 2, the high-protein diet containing 50 % protein. Throughout the gestational period, the pregnant rats received experimental diets.Results showed an increase in homocysteine levels and neuroinflammatory mediators in the offspring's cerebral cortex from pregnant rats supplemented with a high-protein diet throughout pregnancy. Besides decreasing histidine levels in offspring's serum. The results also revealed an impairment in memory and motricity and an increase in anxiety-like behavior in the offspring supplemented with a high-protein diet throughout pregnancy. Our findings showed a significant effect of high-protein diet consumption throughout pregnancy on offspring's neurobiochemistry, which can negatively impact behavioral performance.Our results reinforce the importance of consuming a balanced diet during the gestational period, especially macronutrients such as proteins since the fetus is sensitive to the mother's diet during pregnancy which may impact the development of the offspring.

Quinolinic acid (QUIN) is an important agonist of NMDA receptors that are found at high levels in cases of brain injury and neuroinflammation. Therefore, it is necessary to investigate neuroprotection strategies capable of neutralizing the effects of the QUIN on the brain. Coenzyme Q

PURPOSE Eosinophils are one of the main cells responsible to the inflammatory response in asthma by the release of inflammatory molecules such as cytokines, reactive oxygen species (ROS), cytotoxic granule, eosinophil extracellular trap (EET), and lipid mediators as cysteinyl leukotriene (cysLT). The interconnections between these molecules are not fully understood. Here, we attempted to investigate the cysLT participation in the mechanisms of EET formation in an asthma model of OVA challenge. MATERIALS AND METHODS Before intranasal challenge with OVA, BALB/cJ mice were treated with a 5-lipoxygenase-activating protein (FLAP) inhibitor (MK-886), or with a cysLT1 receptor antagonist (MK-571) and the lung and bronchoalveolar lavage fluid (BALF) were analyzed. RESULTS We showed that OVA-challenged mice treated with MK-886 or MK-571 had a decrease in inflammatory cells, goblet cells hyperplasia, and eosinophil peroxidase (EPO) activity in the airway. However, only OVA-challenged mice treated with MK-571 had an improvement in lung function. Also, treatments with MK-886 or MK-571 decreased Th2 cytokines levels in the airway. Moreover, we observed that OVA-challenged mice treated with MK-886 or MK-571 had a decrease in EET formation in BALF. We also verified that EET release was not due to cell death because the cell viability remained the same among the groups. CONCLUSION We revealed that the decrease in cysLT production or cysLT1 receptor inhibition by MK-886 or/and MK-571 treatments, respectively reduced EET formation in BALF, showing that cysLT regulates the activation process of EET release in asthma.

Elevated levels of homocysteine (Hcy) in the blood, called hyperhomocysteinemia (HHcy), is a prevalent risk factor for it has been shown that Hcy induces oxidative stress and increases microglial activation and neuroinflammation, as well as causes cognitive impairment, which have been linked to the neurodegenerative process. This study aimed to evaluate the effect of mild hyperhomocysteinemia with or without ibuprofen and rivastigmine treatments on the behavior and neurochemical parameters in male rats. The chronic mild HHcy model was chemically induced in Wistar rats by subcutaneous administration of Hcy (4055 mg/kg body weight) twice daily for 30 days. Ibuprofen (40 mg/kg) and rivastigmine (0.5 mg/kg) were administered intraperitoneally once daily. Motor damage (open field, balance beam, rotarod, and vertical pole test), cognitive deficits (Y-maze), neurochemical parameters (oxidative status/antioxidant enzymatic defenses, presynaptic protein synapsin 1, inflammatory profile parameters, calcium binding adapter molecule 1 (Iba1), iNOS gene expression), and cholinergic anti-inflammatory pathway were investigated. Results showed that mild HHcy caused cognitive deficits in working memory, and impaired motor coordination reduced the amount of synapsin 1 protein, altered the neuroinflammatory picture, and caused changes in the activity of catalase and acetylcholinesterase enzymes. Both rivastigmine and ibuprofen treatments were able to mitigate this damage caused by mild HHcy. Together, these neurochemical changes may be associated with the mechanisms by which Hcy has been linked to a risk factor for AD. Treatments with rivastigmine and ibuprofen can effectively reduce the damage caused by increased Hcy levels.

Acute lung injury (ALI) is an inflammatory process, and has high incidence and mortality. ALI and the acute respiratory distress syndrome are two common complications worldwide that result in acute lung failure, sepsis, and death. Pro-inflammatory substances, such as cytokines and chemokines, are responsible for activating the body's defense mechanisms and usually mediate inflammatory processes. Therefore, the research of substances that decrease the uncontrolled response of organism is seen as potential for patients with ALI. Octyl gallate (OG) is a phenolic compound with therapeutic actions namely antimicrobial, antiviral, and antifungal. In this study, we evaluated its action on lipopolysaccharide (LPS)-activated alveolar macrophages RAW 264.7 cells and ALI in male mice. Our results demonstrated protective effects of OG in alveolar macrophages activated with LPS and mice with ALI. The OG treatment significantly decreased the inflammatory markers in both studies in vitro and in vivo. The data suggested that OG can act as an anti-inflammatory agent for ALI.

In asthma, there are high levels of inflammatory mediators, reactive oxygen species (ROS), and eosinophil extracellular traps (EETs) formation in airway. Here, we attempted to investigate the ROS involvement in EETs release and airway inflammation in OVA-challenged mice. Before the intranasal challenge with ovalbumin (OVA), animals were treated with two ROS inhibitors, N-acetylcysteine (NAC) or diphenyleneiodonium (DPI). We showed that NAC treatment reduced inflammatory cells in lung. DPI and NAC treatments reduced eosinophil peroxidase (EPO), goblet cells hyperplasia, proinflammatory cytokines, NFκB p65 immunocontent, and oxidative stress in lung. However, only the NAC treatment improved mitochondrial energy metabolism. Moreover, the treatments with DPI and NAC reduced EETs release in airway. This is the first study to show that ROS are needed for EETs formation in asthma. Based on our results, NAC and DPI treatments can be an interesting alternative for reducing airway inflammation, mitochondrial damage, and EETs release in asthma.

Background: Gut microbiota-derived short-chain fatty-acid (SFCA) acetate protects mice againstRSV A2 strain infection by increasing interferon-β production and expression of interferonstimulated genes (ISGs). However, the role of SFCAs in RSV infection using strains isolated from patients is unknown. Methods: We first used RSV clinical strains isolated from infants hospitalized with RSV bronchiolitis to investigate the effects of in vitro acetate treatment in human pulmonary epithelial cells. We next examined whether acetate treatment is beneficial in a mouse model of RSV infection using clinical isolates. We sought to investigate the relationship of gut microbiota and fecal acetate with disease severity among infants hospitalized with RSV bronchiolitis, and whether treating their respiratory epithelial cells with acetate ex-vivo impacts upon viral load and ISG expression. We further treated epithelial cells from SARS-CoV-2 infected patients with acetate. Findings: In vitro pre-treatment of A549 cells with acetate reduced RSV load after infection with clinical isolates and increased the expression of RIG-I and ISG15. Animals treated with acetate intranasally recovered significantly faster, with reduction in the RSV clinical isolates viral load, and increased lung expression of IFNB1 and the RIG-I receptor. Experiments in RIG-I knockout A549 cells demonstrated that the protection relies on RIG-I presence. Gut microbial profile was associated with bronchiolitis severity and with acetate in stool. Increased acetate levels were associated with increasing oxygen saturation at admission, and shorter duration of fever. Ex-vivo treatment of patients’ respiratory cells with acetate reduced RSV load and increased expression of ISGs OAS1 and ISG15, and virus recognition receptors MAVS and RIG-I, but not IFNB1. These acetate effects were not found on cells from SARS-CoV-2 infected patients. Interpretation: Acetate reduces the severity of RSV infection and RSV viral load through modulation of RIG-I expression. Funding: This study was supported by Rio Grande do Sul Research Foundation FAPERGS (FAPERGS/MS/CNPq/SESRS no. 03/2017 - PPSUS 17/2551-0001380-8 and COVID-19 20/2551-0000258-6), CNPq 312504/2017-9 and by Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior - Brasil (CAPES) - Finance Code 001. P.B., C.V.B. and L.A.B. would like to acknowledge financial support given by CNPq/FAPERGS/CAPES/BNDES to the National Institute of Science and Technology on Tuberculosis (INCT-TB), Brazil [grant numbers: 421703- 2017-2/17-1265-8/14.2.0914.1). Declaration of Interest: The authors declare no competing interests. Ethical Approval: All animal procedures were performed in accordance with protocols approved by CEUA/UNICAMP (protocols 4022-1 and 4599-1).

Background Respiratory viral infections are the leading cause of asthma exacerbations. Eosinophil activation results in the formation of eosinophil extracellular traps (EETs), which release web-like structures of DNA and proteins that bind, disarm and extracellularly kill pathogens. Objective We investigated whether the respiratory syncytial virus (RSV) in vitro could induce EETs in bronchoalveolar lavage fluid eosinophils in a murine model of asthma. Methods BALB/cJ mice (6-8 weeks old) were sensitized with 2 subcutaneous injections of ovalbumin (20 μg) on days 0 and 7, followed by three intranasal challenges with ovalbumin (100 μg) on days 14, 15, and 16 of the protocol. The control group received Dulbecco's phosphate-buffered saline. Bronchoalveolar lavage fluid eosinophils of ovalbumin group or control group were stimulated with RSV (103 PFU/mL) in vitro for 3 hours. After that, culture supernatant was collected to perform the analyses proposed in this study. Results We verified an increase in extracellular DNA concentration in bronchoalveolar lavage fluid eosinophils from ovalbumin group stimulated with RSV (103 PFU/mL) in vitro, which was confirmed by confocal microscopy. We demonstrated that most cells are negative for annexin V and propidium iodide in all groups evaluated. Also, RSV in vitro decreased interferon-ɣ in culture supernatant when compared to the ovalbumin group. Conclusion In this study, we demonstrated for the first time that RSV in vitro induces EETs formation in eosinophils from asthmatic mice.

This study aimed to evaluate the effects of early-life exposure to different extracts of Angiostrongylus cantonensis (A. cantonensis) on airway inflammation in an allergic asthma model. The total soluble extract (TE) and the soluble extracts of the digestive (AcD), reproductive (AcR), and cuticle (AcC) systems of A. cantonensis were used for immunisation before ovalbumin (OVA)-sensitisation/challenge in an OVA-induced allergic asthma model. The initial hypothesis of the study was that some soluble extract of the systems (AcD, AcR, or AcC) could be more potent to the modulation of inflammation than the TE. Our data, however, shows that immunisation with the TE is more promising because it decreased the high influx of inflammatory cells on airways and promoted an increase of interferon-γ (IFN-ɣ) and interleukin-10 (IL-10) levels. Besides this, the immunisation with the TE also led to a reduction of goblet cells and mucus overproduction in the lung tissue of asthmatic mice. We believe that the extracts have a distinct capacity to modulate the immune system, due to the TE possessing a greater variability of molecules, which together leads to control of airway inflammation. In conclusion, this is the first study to reveal that the TE of A. cantonensis adult worms has a greater potential for developing a novel therapeutic for allergic asthma.

Studies have shown autophagy participation in the immunopathology of inflammatory diseases. However, autophagy role in asthma and in eosinophil extracellular traps (EETs) release is poorly understood. Here, we attempted to investigate the autophagy involvement in EETs release and in lung inflammation in an experimental asthma model. Mice were sensitized with ovalbumin (OVA), followed by OVA challenge. Before the challenge with OVA, mice were treated with an autophagy inhibitor, 3-methyladenine (3-MA). We showed that 3-MA treatment decreases the number of eosinophils, eosinophil peroxidase (EPO) activity, goblet cells hyperplasia, proinflammatory cytokines, and nuclear factor kappa B (NFκB) p65 immunocontent in the lung. Moreover, 3-MA was able to improve oxidative stress, mitochondrial energy metabolism, and Na+ , K+ -ATPase activity. We demonstrated that treatment with autophagy inhibitor 3-MA reduced EETs formation in the airway. On the basis of our results, 3-MA treatment can be an interesting alternative for reducing lung inflammation, oxidative stress, mitochondrial damage, and EETs formation in asthma.

Asthma is a highly prevalent chronic inflammatory lung disease characterized by airway hyperresponsiveness to allergens, airway edema, and increased mucus secretion. Such mucus can be liquefied by recombinant human deoxyribonuclease (rhDNase), in which efficacy of rhDNase has been well documented in patients with cystic fibrosis, but little studied in asthma. In the present study, we investigated whether rhDNase intranasal administration improved inflammation and pulmonary function in an experimental model of asthma.Mice were sensitized by two subcutaneous injections of ovalbumin (OVA), on days 0 and 7, followed by three intranasal challenges with OVA on days 14, 15, and 16. A control group, replacing OVA by DPBS, was included. On days 15 and 16, after 2 hours of OVA challenge, mice received 1 mg/mL of intranasal rhDNase.We showed that rhDNase decreased significantly the airway resistance and reduced EETs formation and globet cells hyperplasia.Our results suggest that extracellular DNA in mucus play a role in lower airways obstruction in OVA asthma protocol and that the treatment with rhDNase improved lung function and DNA extracellular traps, with no direct cellular anti-inflammatory effects.

The inflammatory cells infiltrating the airways produce several mediators, such as reactive oxygen species (ROS). ROS and the oxidant-antioxidant imbalance might play an important role in the modulation of airways inflammation. In order to avoid the undesirable effects of ROS, various endogenous antioxidant strategies have evolved, incorporating both enzymatic and non-enzymatic mechanisms. Recombinant human deoxyribonuclease (rhDNase) in clinical studies demonstrated a reduction in sputum viscosity, cleaving extracellular DNA in the airways, and facilitating mucus clearance, but an antioxidant effect was not studied so far. Therefore, we evaluated whether the administration of rhDNase improves oxidative stress in a murine model of asthma. Mice were sensitized by two subcutaneous injections of ovalbumin (OVA), on days 0 and 7, followed by three lung challenges with OVA on days 14, 15, and 16. On days 15 and 16, after 2 h of the challenge with OVA, mice received 1 mg/mL of rhDNase in the lungs. Bronchoalveolar lavage fluid and lung tissue were obtained on day 17, for inflammatory and oxidative stress analysis. We showed that rhDNase did not alter the population of inflammatory cells, such as eosinophil cells, in OVA-treated rhDNase group but significantly improved oxidative stress in lung tissue, by decreasing oxygen reactive species and increasing superoxide dismutase/catalase ratio, glutathione peroxidase activity, and thiol content. Our data provide the first evidence that rhDNase decreases some measures of oxidative stress and antioxidant status in a murine model of asthma, with a potential antioxidant effect to be further studied in human asthma.

Asthma is associated with a loss of the structural integrity of airway epithelium and dysfunction of the physical barrier, which protects airways from external harmful factors. Granulocyte activation causes the formation of extracellular traps, releasing web-like structures of DNA and proteins, being important to kill pathogens extracellularly. We investigated whether eosinophils infiltrating airways in an experimental model of asthma would induce eosinophil extracellular traps (EETs) in bronchoalveolar lavage fluid and lung tissue. We showed that an ovalbumin (OVA) asthma protocol presented a significant increase in eosinophil counts with increased extracellular DNA in bronchoalveolar lavage fluid as well as in lung tissue, confirming the presence of DNA traps colocalized with eosinophil peroxidase. EETs formation was reversed by DNase treatment. With these approaches, we demonstrated for the first time that OVA-challenged mice release extracellular DNA traps, which could aggravate pulmonary dysfunction.

Background Tyrophagus putrescentiae (Tp) is a source of aeroallergen that causes allergic diseases. Objective To describe an acute and chronic murine model of allergic asthma with Tp extract with no systemic sensitization and no use of adjuvant. Methods Mites from dust sample were cultured and a raw extract was produced. Female BALB/c mice (6-8 weeks) were challenged intranasally with Tp extract or Dulbecco's phosphate-buffered saline, for 10 consecutive days (acute protocol) or for 6 weeks (chronic protocol). Twenty-four hours after the last intranasal challenge, bronchoalveolar lavage fluid (BALF) was performed for total and differential cells count, cytokine analysis, and eosinophil peroxidase activity. Lung tissue was also removed for histopathologic analysis. Results Tp extract has shown a significant increase in total cells count from BALF as well as an increase in absolute eosinophils count, eosinophil peroxidase activity, interleukin (IL)-5 and IL-13 levels, in both acute and chronic protocols. Peribronchovascular infiltrate, goblet cells hyperplasia and collagen deposition were shown in the airways of acute and chronic Tp-exposed mice. Conclusion Our data suggest that the intranasal exposure to Tp extract, with no systemic sensitization and no use of adjuvants, induces a robust allergic inflammation in the lungs of mice, in both acute and chronic models. Our Tp extract seems to be a potent allergen extract which may be used in asthma model studies.