6-Shogaol Exerts a Neuroprotective Factor in Offspring after Maternal Immune Activation in Rats.

6-Shogaol is one of the main active phenolic components of ginger and has neuroprotective effects by protecting brain against the oxidative stress and regulate the levels of neurotrophic factors. The objective of the present study was to verify the effect of 6-shogaol on neurochemical parameters in offspring after maternal immune activation by lipopolysaccharide (LPS) in rats. Twelve pregnant Wistar rats received 100 µg/kg of LPS or saline solution on the gestational day 9.5. Male offspring participated in the study and from the postnatal days (PND) 30 and 55, respectively, they were supplemented with 6-shogaol or saline solution, by gavage at a dose of 10 mg/kg/day, orally for 5 days. In PND 37 and 62, analysis of kinase signaling regulated by extracellular signal 1/2 (ERK 1/2), levels of neurotrophic factor derived from the brain (BDNF), and neuron-specific enolase (NSE), lipid and protein oxidative damage was evaluated by 4-hydroxy-2-nonenal (HNE) and 3-nitrotyrosine (3-NT), respectively, and myeloperoxidase (MPO) activity was performed in the hippocampus. Prenatal exposure to LPS significantly decreased ERK and BDNF levels in PND 37 and 62, increased NSE levels and lipid damage in rats in PND 37, and increased 3-NT level in rats in PND 62. With treatment using 6-shogaol, an increase in ERK and BDNF levels was identified in PND 37 and 62 and a reduction in HNE and MPO activity in rats in PND 37 and 62, respectively. 6-Shogaol positively increased markers of neuronal growth, plasticity and synaptic activity and reduced oxidative damage in the hippocampus in an animal model of autism by maternal immune activation.

Neurological impairment caused by Schistosoma mansoni systemic infection exhibits early features of idiopathic neurodegenerative disease.

Schistosomiasis, a neglected tropical disease caused by trematodes of the Schistosoma genus, affects over 250 million people around the world. This disease has been associated with learning and memory deficits in children, whereas reduced attention levels, impaired work capacity, and cognitive deficits have been observed in adults. Strongly correlated with poverty and lack of basic sanitary conditions, this chronic endemic infection is common in Africa, South America, and parts of Asia and contributes to inhibition of social development and low quality of life in affected areas. Nonetheless, studies on the mechanisms involved in the neurological impairment caused by schistosomiasis are scarce. Here, we used a murine model of infection with Schistosoma mansoni in which parasites do not invade the central nervous system to evaluate the consequences of systemic infection on neurologic function. We observed that systemic infection with S. mansoni led to astrocyte and microglia activation, expression of oxidative stress-induced transcription factor Nrf2, oxidative damage, Tau phosphorylation, and amyloid-ß peptide accumulation in the prefrontal cortex of infected animals. We also found impairment in spatial learning and memory as evaluated by the Morris water maze task. Administration of anthelmintic (praziquantel) and antioxidant (N-acetylcysteine plus deferoxamine) treatments was effective in inhibiting most of these phenotypes, and the combination of both treatments had a synergistic effect to prevent such changes. These data demonstrate new perspectives toward the understanding of the pathology and possible therapeutic approaches to counteract long-term effects of systemic schistosomiasis on brain function.

Acromegaly in dogs and cats.

Acromegaly is an endocrine disease that leads to elevated production and secretion of growth hormone (GH). It can occur in adult and aged cats and is usually associated with neoplasms, such as functional pituitary macroadenoma of somatotropic cells. In dogs it is usually related to an increase in serum progesterone that induces production of GH by the mammary glands. The main clinical signs are related to insulin resistance and the anabolic effect induced by GH: polyuria, polydipsia, polyphagia, increased tissue growth, weight gain, prognathism, and other changes. The condition can be diagnosed from clinical signals and imaging associated to measurement of serum concentrations of GH and insulin-like growth factor 1 (IGF-1, also known as somatomedin C). The main therapeutic modalities are radiotherapy, hypophysectomy, and several drugs such as somatostatin analogs, dopaminergic agonists and GH receptor antagonists. The present review aims to provide a relevant animal model of acromegaly with an update on the therapeutic approach that may help clinicians to consider the GH axis-IGF-1 system, its pathogenesis and the clinical signs induced by this hormonal disorder.

Systemic Response to Infection Induces Long-Term Cognitive Decline: Neuroinflammation and Oxidative Stress as Therapeutical Targets.

In response to pathogens or damage signs, the immune system is activated in order to eliminate the noxious stimuli. The inflammatory response to infectious diseases induces systemic events, including cytokine storm phenomenon, vascular dysfunction, and coagulopathy, that can lead to multiple-organ dysfunction. The central nervous system (CNS) is one of the major organs affected, and symptoms such as sickness behavior (depression and fever, among others), or even delirium, can be observed due to activation of endothelial and glial cells, leading to neuroinflammation. Several reports have been shown that, due to CNS alterations caused by neuroinflammation, some sequels can be developed in special cognitive decline. There is still no any treatment to avoid cognitive impairment, especially those developed due to systemic infectious diseases, but preclinical and clinical trials have pointed out controlling neuroinflammatory events to avoid the development of this sequel. In this minireview, we point to the possible mechanisms that triggers long-term cognitive decline, proposing the acute neuroinflammatory events as a potential therapeutical target to treat this sequel that has been associated to several infectious diseases, such as malaria, sepsis, and, more recently, the new SARS-Cov2 infection.

Peripheral leptin signaling persists in innate immune cells during diet-induced obesity.

Leptin is a pleiotropic adipokine that regulates immunometabolism centrally and peripherally. Obese individuals present increased levels of leptin in the blood and develop hypothalamic resistance to this adipokine. Here we investigated whether leptin effects on the periphery are maintained despite the hypothalamic resistance. We previously reported that leptin injection induces in vivo neutrophil migration and peritoneal macrophage activation in lean mice through TNF-α- and CXCL1-dependent mechanisms. However, leptin effects on leukocyte biology during obesity remain unclear. In this study, we investigated the in vivo responsiveness of leukocytes to i.p. injected leptin in mice with diet-induced obesity (DIO). After 14-16 wk, high-sucrose, high-fat diet (HFD)-fed mice showed hyperglycemia, hyperleptinemia, and dyslipidemia compared to normal-sucrose, normal-fat diet (ND). Exogenous leptin did not reduce food intake in DIO mice in contrast to control mice, indicating that DIO mice were centrally resistant to leptin. Regardless of the diet, we found increased levels of TNF-α and CXCL1 in the animals injected with leptin, alongside a pronounced neutrophil migration to the peritoneal cavity and enhanced biogenesis of lipid droplets in peritoneal macrophages. Supporting our in vivo results, data from ex vivo leptin stimulation experiments confirmed hypothalamic resistance in DIO mice, whereas bone marrow cells responded to leptin stimulation through mTOR signaling despite obesity. Altogether, our results show that leukocytes responded equally to leptin in ND- or HFD-fed mice. These results support a role for leptin in the innate immune response also in obesity, contributing to the inflammatory status that leads to the development of metabolic disease.

Simvastatin Posttreatment Controls Inflammation and Improves Bacterial Clearance in Experimental Sepsis.

Sepsis is characterized by a life-threatening organ dysfunction caused by an unbalanced host response to microbe infection that can lead to death. Besides being currently the leading cause of death in intensive care units worldwide, sepsis can also induce long-term consequences among survivors, such as cognitive impairment. Statins (lipid-lowering drugs widely used to treat dyslipidemia) have been shown to possess pleiotropic anti-inflammatory and antimicrobial effects. These drugs act inhibiting 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, an enzyme that catalyzes the conversion of HMG-CoA to mevalonate, the limiting step in cholesterol biosynthesis. In this work, we evaluated the therapeutic effects of simvastatin in an animal model of sepsis. In previous study from our group, statin pretreatment avoided cognitive damage and neuroinflammation in sepsis survivors. Herein, we focused on acute inflammation where sepsis was induced by cecal ligation and puncture (CLP), and the animals were treated with simvastatin (2 mg/kg) 6 h after surgery. We measured plasma biochemical markers of organ dysfunction, cell migration, cell activation, bacterial elimination, production of nitric oxide 24 h after CLP, survival rate for 7 days, and cognitive impairment 15 days after CLP. One single administration of simvastatin 6 h after CLP was able to prevent both liver and kidney dysfunction. In addition, this drug decreased cell accumulation in the peritoneum as well as the levels of TNF-α, MIF, IL-6, and IL-1ß. Simvastatin diminished the number of bacterial colony forming units (CFU) and increased the production of nitric oxide production in the peritoneum. Simvastatin treatment increased survival for the first 24 h, but it did not alter survival rate at the end of 7 days. Our results showed that posttreatment with simvastatin hampered organ dysfunction, increased local production of nitric oxide, improved bacterial clearance, and modulated inflammation in a relevant model of sepsis.

In vivo and in vitro antimalarial effect and toxicological evaluation of the chloroquine analogue PQUI08001/06.

Antimalarial interventions mostly rely upon drugs, as chloroquine. However, plasmodial strains resistant to many drugs are constantly reported, leading to an expansion of malaria cases. Novel approaches are required to circumvent the drug resistance issue. Here, we describe the antimalarial potential of the chloroquine analogue 2-[[2-[(7-chloro-4-quinolinyl)amino]ethyl]amino] ethanol (PQUI08001/06). We observed that PQUI08001/06 treatment reduces parasitemia of both chloroquine-resistant and -sensitive strains of Plasmodium falciparum in vitro and P. berghei in vivo. Our data suggests that PQUI08001/06 is a potential antimalarial therapeutic alternative approach that could also target chloroquine-resistant plasmodial strains.

Effects of ω-3 fatty acids on stereotypical behavior and social interactions in Wistar rats prenatally exposed to lipopolysaccarides.

OBJECTIVE: Supplementation with ω-3 polyunsaturated fatty acids (PUFAs) can positively contribute to neurologic development, modulating inflammatory responses, promoting homeostasis, and having a positive effect on animal behaviors associated with mental disorders. The aim of this study was to evaluate behavioral and biochemical effects of ω-3 fatty acid supplementation in an animal model for mental disorders by prenatal maternal exposure to lipopolysaccardies (LPS) from the maternal immune activation. METHODS: Twelve pregnant Wistar rats were used. Each rat received 100 µg/kg of LPS or saline solution on gestational day (GD) 9.5. The offspring remained with mothers until weaning and from postnatal day (PND) 30 were supplemented with ω-3 PUFA or saline solution by gavage at a dose of 0.8 g/kg orally for 21 d. On PND 52, the animals underwent behavioral tests; then, they were sacrificed, and the brain structures were dissected and analyzed by levels: neuron-specific enolase (NSE), brain-derived neurotrophic factor, and transforming growth factor (TGF)-ß. RESULT: Prenatal exposure to LPS significantly increased the episodes of stereotyped movements and decreased social interaction in the offspring (P = 0.009 and P = 0.001, respectively), after ω-3 PUFA supplementation these parameters reversed (P = 0.005 and P = 0.013, respectively). Significant changes also were identified in the biochemical analysis in NSE and TGF-ß in the brain structures; these conditions were reversed after ω-3 PUFA supplementation. CONCLUSION: Supplementation with ω-3 PUFA reversed animal behaviors that often are observed in autism and other mental disorders in rats prenatally exposed to LPS, and also exerted neuroprotective effects in marker levels of neuronal damage and expression of TGF-ß.

Combined therapy with metformin and insulin attenuates systemic and hepatic alterations in a model of high-fat diet-/streptozotocin-induced diabetes.

In this study we have explored the pathogenesis of the hepatic alterations which occur in diabetes and the modulation of these complications by the combination of metformin adjunct treatment and insulin monotherapy. For this purpose, diabetic rats were treated with insulin (DM + Ins) or metformin plus insulin (DM + Met + Ins). Biochemical and cardiometabolic parameters were analysed by spectrophotometry. Intravital microscopy was used to study the hepatic microcirculation. In the liver tissue, real-time PCR was used to analyse oxidative stress enzymes, inflammatory markers and receptors for advanced glycation end products (AGE) (RAGE) gene expression. Lipid peroxidation was assessed by thiobarbituric acid reactive species (TBARs) analyses. AGE deposition and RAGE protein expression were studied by fluorescence spectrophotometry and Western blot respectively. Body weight, %HbA1c , urea, total proteins and oxidative stress parameters were found to be similarly improved by insulin or Met + Ins treatments. On the other hand, Met + Ins treatment showed a more pronounced effect on fasting blood glucose level than insulin monotherapy. Fructosamine, uric acid, creatinine, albumin and amylase levels and daily insulin dose requirements were found to be only improved by the combined Met + Ins treatment. Liver, renal and pancreatic dysfunction markers were found to be more positively affected by metformin adjunct therapy when compared to insulin treatment. Liver microcirculation damage was found to be completely protected by Met + Ins treatment, while insulin monotherapy showed no effect. Our results suggest that oxidative stress, microcirculatory damage and glycated proteins could be involved in the aetiology of liver disease due to diabetes. Additionally, metformin adjunct treatment improved systemic and liver injury in induced diabetes and showed a more pronounced effect than insulin monotherapy.

ExoU-induced redox imbalance and oxidative stress in airway epithelial cells during Pseudomonas aeruginosa pneumosepsis.

ExoU is a potent proinflammatory toxin produced by Pseudomonas aeruginosa, a major agent of severe lung infection and sepsis. Because inflammation is usually associated with oxidative stress, we investigated the effect of ExoU on free radical production and antioxidant defense mechanisms during the course of P. aeruginosa infection. In an experimental model of acute pneumonia, ExoU accounted for increased lipid peroxidation in mice lungs as soon as 3 h after intratracheal instillation of PA103 P. aeruginosa strain. The contribution of airway cells to the generation of a redox imbalance was assessed by in vitro tests carried out with A549 airway epithelial cells. Cultures infected with the ExoU-producing PA103 P. aeruginosa strain produced significantly increased concentrations of lipid hydroperoxides, 8-isoprostane, reactive oxygen intermediates, peroxynitrite and nitric oxide (NO), when compared to cells infected with exoU-deficient mutants. Overproduction of NO by PA103-infected cells likely resulted from overexpression of both inducible and endothelial NO synthase isoforms. PA103 infection was also associated with a significantly increased activity of superoxide dismutase (SOD) and decreased levels of reduced glutathione (GSH), a major antioxidant compound. Our findings unveil another potential mechanism of tissue damage during infection by ExoU-producing P. aeruginosa strains.

Atividade anti-inflamatória do óleo-resina da Copaífera reticulata em modelo inflamatório de edema de pata / Anti-inflammatory activity of the oil-resin Copaífera reticulata of model inflamatory paw edema

Objetivo: avaliar a ação do óleo-resina de copaíba da espécie copaifera reticulata como anti-inflamatório em modelos experimentais de reação inflamatória aguda. Método: o estudo experimental foi realizado no Laboratório de Imunofarmacologia da Fundação Instituto Oswaldo Cruz ? FIOCRUZ/RJ, foram utilizados 30 (trinta) camundongos da linhagem Swiss Webster (SW). O óleo-resina de copaíba utilizada foi extraído de árvore da espécie Copaífera reticulata. O modelo de inflamação aguda induzida por carragenina foi utilizado para avaliar o efeito anti-inflamatório das concentrações, foi utilizado o teste estatístico de Kruskal-Wallis para comparar os valores medianos conforme os grupos com nível de significância alfa = 0,05. Resultados: no grupo C500 ocorreu significativa redução do volume no instante T3; somente os grupos Indo e C10 apresentaram significativa redução do volume em T6. Não houve diferença estatisticamente significante no Índice de Inibição do Edema nos grupos (Indo, C10, C100 e C500) nos intantes T1, T3 e T6. Conclusão: a atividade anti-inflamatória do óleo-resina foi confirmada pelo modelo do edema de pata induzido por carragenina através da redução do volume deslocado.

Objective: To evaluate the action of the oil-resin of Copaiba Copaifera reticulata as anti-inflammatory effect in experimental models of acute inflammatory reaction. Method: A total of 30 (thirty) mice of Swiss strain Webster (SW). The oil-resin of Copaiba used was extracted from tree species Copaifera reticulata. The model of acute inflammation induced by carrageenan was used to evaluate the anti-inflammatory effect of the extracts, we used the statistical test of Kruskal-Wallis test to compare the median values for the different groups with a significance level alpha = 0.05. Results: The group C500 was a significant reduction in the volume at time T3, only the Indus and C10 groups showed significant reduction in volume at T6. There was no statistically significant difference in the Index of Inhibition of edema in groups (Indo, C10, C100 and C500), in the instant, T1, T3 and T6. Conclusion: The anti-inflammatory activity of oil-resin was confirmed by the model of paw edema induced by carrageenan by reducing the volume displaced.

Immunosuppressive effects of Echinodorus macrophyllus aqueous extract.

Echinodorus macrophyllus is a medicinal plant, popularly known in Brazil as "chapéu de couro", used to treat rheumatic diseases, which are usually characterized by exacerbated T and B lymphocyte response. We have evaluated the effects of the aqueous extract of Echinodorus macrophyllus (AEEm) on these cell functions, proliferation, and nitric oxide production. Mice treated orally for 7 days with AEEm had inhibited B cell antibody production (0.5mg/kg b.w.) and delayed type hypersensitivity (0.5 and 5mg/kg b.w.) mediated by T cells, reducing subcutaneous tissue leukocyte infiltration. AEEm inhibited, in vitro, NO production by stimulating J774 cells in a dose-dependent manner, with no cytotoxicity. We have demonstrated, for the first time, its immunosuppressive effect. This immunosuppressive effect supports a potential therapeutic use of AEEm to control exacerbated humoral and/or cellular immune response, as in autoimmune rheumatic diseases. However, it is important to be cautious about its indiscriminate popular use to avoid side effects, mainly in immunodeficiency diseases.

Antinociceptive properties of ethanolic extract and fractions of Pterodon pubescens Benth. seeds.

We have previously demonstrated that the hydroalcoholic extract from Pterodon pubescens Benth. seeds (sucupira branca, Leguminosae) exhibits anti-arthritic activity and that its oleaginous extract (OEP) and PF1 fraction exhibit acute and topic anti-edematogenic activities. In this work, we studied the antinociceptive activity of OEP and its fractions on the acetic acid-induced abdominal constriction and formalin assays in SW male mice. OEP was obtained by ethanol extraction and its four fractions by sequential liquid-liquid extraction. PF2 GC/MS profile indicated it contains furane diterpenes derivatives of vouacapan and non-vouacapan compounds. The antinociceptive properties were demonstrated to OEP and predominantly to PF1 and PF2 by the writhing test. In the formalin assay, PF1 inhibited both phases and PF2 inhibited mainly the late one. Then, PF1 and PF2 seemed to present antinociceptive effects by different mechanisms, peripheral and/or central inhibitory ones, and showed maximum antinociceptive properties with very low doses, providing a rationale for its popular use in pain disorders.