Toxic metals that interact with thiol groups and alteration in insect behavior.

Toxic metals, such as mercury (Hg), lead (Pb), cadmium (Cd), and copper (Cu), are widespread in the biosphere, and human activities have contributed to their continuous release into the ecosystems. Metal-induced toxicity has been extensively studied in mammals; however, the effects of these metals on insects' behavior have been explored to far lesser degree. As the main mechanism of toxicity, the cationic metals, explored in this review, have high affinity for thiol-containing molecules, disrupting the function of several proteins and low-molecular-weight thiol-containing molecules.

Hydrogen Sulfide (HS) Signaling as a Protective Mechanism against Endogenous and Exogenous Neurotoxicants.

In view of the significant role of HS in brain functioning, it is proposed that HS may also possess protective effects against adverse effects of neurotoxicants. Therefore, the objective of the present review is to discuss the neuroprotective effects of HS against toxicity of a wide spectrum of endogenous and exogenous agents involved in the pathogenesis of neurological diseases as etiological factors or key players in disease pathogenesis. Generally, the existing data demonstrate that HS possesses neuroprotective effects upon exposure to endogenous (amyloid β, glucose, and advanced-glycation end-products, homocysteine, lipopolysaccharide, and ammonia) and exogenous (alcohol, formaldehyde, acrylonitrile, metals, 6-hydroxydopamine, as well as 1-methyl-4-phenyl- 1,2,3,6- tetrahydropyridine (MPTP) and its metabolite 1-methyl-4-phenyl pyridine ion (MPP)) neurotoxicants.

Ghrelin attenuates methylmercury-induced oxidative stress in neuronal cells.

Methylmercury (MeHg) is a global pollutant, which can cause damage to the central nervous system at both high-acute and chronic-low exposures, especially in vulnerable populations, such as children and pregnant women. Nowadays, acute-high poisoning is rare. However, chronic exposure to low MeHg concentrations via fish consumption remains a health concern.

The antioxidant role of STAT3 in methylmercury-induced toxicity in mouse hypothalamic neuronal GT1-7 cell line.

Oxidative stress, impairment of antioxidant defenses, and disruption of calcium homeostasis are associated with the toxicity of methylmercury (MeHg). Yet, the relative contribution and interdependence of these effects and other molecular mechanisms that mediate MeHg-induced neurotoxicity remain uncertain. The signal transducer and activator of transcription 3 (STAT3) is a transcription factor that regulates the expression of anti-apoptotic and cell cycle progression genes.

Chronic exposure to methylmercury enhances the anorexigenic effects of leptin in C57BL/6J male mice.

Several studies have demonstrated that heavy metals disrupt energy homeostasis. Leptin inhibits food intake and decreases body weight through activation of its receptor in the hypothalamus. The impact of heavy metals on leptin signaling in the hypothalamus is unclear.

JM-20 protects memory acquisition and consolidation on scopolamine model of cognitive impairment.

Objective: JM-20, a novel hybrid synthetic molecule, has been reported to have antioxidant, mitoprotective, anti-excitotoxic, anti-apoptotic and anti-inflammatory properties. However, the neuroprotective effect of JM-20 against memory impairment in preclinical AD-like models has not been analyzed. The aim of this study was to evaluate the potential neuroprotection of JM-20 that preserves essential memory process from cholinergic dysfunction and other molecular damages.

Astrocyte-neuron interaction in diphenyl ditelluride toxicity directed to the cytoskeleton.

Diphenylditelluride (PhTe) is a neurotoxin that disrupts cytoskeletal homeostasis. We are showing that different concentrations of (PhTe) caused hypophosphorylation of glial fibrillary acidic protein (GFAP), vimentin and neurofilament subunits (NFL, NFM and NFH) and altered actin organization in co-cultured astrocytes and neurons from cerebral cortex of rats. These mechanisms were mediated by N-methyl-d-aspartate (NMDA) receptors without participation of either L-type voltage-dependent calcium channels (L-VDCC) or metabotropic glutamate receptors.

Evaluation of methylglyoxal toxicity in human erythrocytes, leukocytes and platelets.

Methylglyoxal (MG) is a reactive dicarbonyl metabolite originated mainly from glucose degradation pathway that plays an important role in the pathogenesis of diabetes mellitus (DM). Reactions of MG with biological macromolecules (proteins, DNA and lipids) can induce cytotoxicity and apoptosis. Here, human erythrocytes, leukocytes and platelets were acutely exposed to MG at concentration ranging from 0.

Scientific Performance of Brazilian Researchers in Pharmacology with grants from CNPq: A comparative study within the Brazilian categories.

In Brazil, scientific performance of researchers is one important criteria for decision-making in grant allocation. In this context, this study aimed to evaluate and compare the profile of 82 seniors' investigators (graded as level 1A-D) which were receiving CNPq (National Council for Scientific and Technological Development) productivity grant in Pharmacology, by analyzing the pattern of citation of their papers and h-index. Total documents, citations (with and without self-citations) and h-index (with and without self-citations) were retrieved from the Scopus database.

Diphenyl diselenide attenuates oxidative stress and inflammatory parameters in ulcerative colitis: A comparison with ebselen.

Objetive: The aim of this study was to evaluate the effects of diphenyl diselenide (PhSe)2 and ebselen (EB) in ulcerative colitis (UC) induced by dextran sulfate sodium (DSS) in rats.

Methods: The effects of (PhSe)2 and EB in rats submitted to DSS-induced colitis were determined by measurement of oxidative stress parameters, inflammatory response and bowel histopathological alterations.

Results: Animals developed moderate to severe neutrophil infiltration in histopathology assay in DSS rats and (PhSe)2 improved this response.

RAPD and SCAR markers as potential tools for detection of milk origin in dairy products: Adulterant sheep breeds in Serra da Estrela cheese production.

Serra da Estrela Protected Designation of Origin (PDO) cheese is the most famous Portuguese cheese and has a high commercial value. However, the adulteration of production with cheaper/lower-quality milks from non-autochthones ovine breeds compromises the quality of the final product and undervalues the original PDO cheese. A Randomly Amplified Polymorphic DNA (RAPD) method was developed for efficient detection of adulterant breeds in milk mixtures used for fraudulent production of this cheese.

Selenium and mercury levels in rat liver slices co-treated with diphenyl diselenide and methylmercury.

Organoseleno-compounds have been investigated for its beneficial effects against methylmercury toxicity. In this way, diphenyl diselenide (PhSe)2 was demonstrated to decrease Hg accumulation in mice, protect against MeHg-induced mitochondrial dysfunction, and protect against the overall toxicity of this metal. In the present study we aimed to investigate if co-treatment with (PhSe)2 and MeHg could decrease accumulation of Hg in liver slices of rats.

Gas chromatography coupled with mass spectrometric characterization of Curcuma longa: Protection against pathogenic microbes and lipid peroxidation in rat's tissue homogenate.

The present study was designed to investigate the mineral content and antimicrobial activity of Curcuma Longa extracts and its essential oil. We also determined the lipid peroxidation inhibition activity of the ethanolic extract against sodium nitroprusside (SNP) induced thiobarbituric acid reactive species (TBARS) formation in rat's brain, kidney and liver homogenates. Major constituents of essential oil identified by gas chromatography and mass spectrometry (GCMS) were beta-sesquiphellandrene (38.

4-Organoseleno-Isoquinolines Selectively and Reversibly Inhibit the Cerebral Monoamine Oxidase B Activity.

Isoquinolines are formed endogenously as metabolites of neurotransmitters and are studied because they have structures similar to neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and selegiline, a selective inhibitor of MAO-B. This study investigated a possible in vitro inhibitory activity of new 4-organochalcogen-isoquinoline derivatives, containing sulfur 1, selenium 2 or tellurium 3 on MAO-A and B activities. Considering that the non-substituted selenoisoquinoline derivative 2 showed the best inhibitory profile (IC50 = 36.

Methylmercury and brain development: A review of recent literature.

Methylmercury (MeHg) is a potent environmental pollutant, which elicits significant toxicity in humans. The central nervous system (CNS) is the primary target of toxicity, and is particularly vulnerable during development. Maternal exposure to MeHg via consumption of fish and seafood can have irreversible effects on the neurobehavioral development of children, even in the absence of symptoms in the mother.

Association of Oxidative Stress with Psychiatric Disorders.

Background: When concentrations of both reactive oxygen species and reactive nitrogen species exceed the antioxidative capability of an organism, the cells undergo oxidative impairment. Impairments in membrane integrity and lipid and protein oxidation, protein mutilation, DNA damage, and neuronal dysfunction are some of the fundamental consequences of oxidative stress.

Methods: The purpose of this work was to review the associations between oxidative stress and psychological disorders.

Neuroprotection of luteolin against methylmercury-induced toxicity in lobster cockroach Nauphoeta cinerea.

Luteolin (3', 4', 5, 7-tetrahydroxyflavone) is a polyphenolic compound found in foods of plant origin and has been reported to possess antioxidant and neuroprotective properties. However, there is dearth of information on the beneficial effects of luteolin on methylmercury (MeHg), a long-established neurotoxic compound in animals and humans. This study evaluated the effect of luteolin on MeHg-induced behavioral and biochemical deficits, using lobster cockroach Nauphoeta cinerea as an alternative and complementary animal model.

Chemical Characterization and Trypanocidal, Leishmanicidal and Cytotoxicity Potential of Lantana camara L. (Verbenaceae) Essential Oil.

Drug resistance in the treatment of neglected parasitic diseases, such as leishmaniasis and trypanosomiasis, has led to the search and development of alternative drugs from plant origins. In this context, the essential oil extracted by hydro-distillation from Lantana camara leaves was tested against Leishmania braziliensis and Trypanosoma cruzi. The results demonstrated that L.

Diphenyl Diselenide Protects Against Mortality, Locomotor Deficits and Oxidative Stress in Drosophila melanogaster Model of Manganese-Induced Neurotoxicity.

Several experimental and epidemiological reports have associated manganese exposure with induction of oxidative stress and locomotor dysfunctions. Diphenyl diselenide (DPDS) is widely reported to exhibit antioxidant, anti-inflammatory and neuroprotective effects in in vitro and in vivo studies via multiple biochemical mechanisms. The present study investigated the protective effect of DPDS on manganese-induced toxicity in Drosophila melanogaster.

Ethanolic extract of Nigella sativa protects Fe(II) induced lipid peroxidation in rat's brain, kidney and liver homogenates.

The study describes the effect of ethanolic extract of Nigella sativa against Fe(II) induced lipid peroxidation. Basal and Fe(II) induced thiobarbituric acid reactive species (TBARS) production was significantly inhibited by the ethanolic extract of Nigella sativa at 25-200 μg/ml. Our data revealed that the extract has high DPPH radical scavenging activity at highest tested concentrations.

Polyphenolic Composition and Evaluation of Antioxidant Activity, Osmotic Fragility and Cytotoxic Effects of Raphiodon echinus (Nees & Mart.) Schauer.

Raphiodon echinus (R. echinus) is used in Brazilian folk medicine for the treatment of inflammation, coughs, and infectious diseases. However, no information is available on the potential antioxidant, cytotoxicity and genotoxicity of this plant.

Behavioral and neurochemical effects induced by reserpine in mice.

Rationale: Reserpine, a monoamine-depleting agent, which irreversibly and non-selectively blocks the vesicular monoamine transporter, has been used as an animal model to study several neurological disorders, including tardive dyskinesia and Parkinson's disease.

Objective: The purpose of this study was to examine if motor deficits induced by reserpine in mice could be related to alterations in the expression of dopaminergic system proteins such as tyrosine hydroxylase (TH) and dopamine transporter (DAT) and in the activity of monoamine oxidase (MAO).

Methods: Mice received either vehicle or reserpine (0.

Diphenyl diselenide improves the antioxidant response via activation of the Nrf-2 pathway in macrophage cells.

Diphenyl diselenide [(PhSe)2] is an organoselenium compound that can mimic endogenous antioxidant enzymes, such as glutathione peroxidase (GPx), or be metabolized by thioredoxin reductase to form selenol intermediate, which can copy the function of the antioxidant selenoenzymes. This compound has shown potential role in preventing atherosclerosis and other oxidative stress-related diseases. The understanding of the underlying mechanism by which (PhSe)2 modulates the glutathione-related antioxidant defenses is a relevant question.