Nitrooxidative Stress and Neuroinflammation Caused by Air Pollutants Are Associated with the Biological Markers of Neurodegenerative Diseases.

Millions of people around the world are exposed to air pollutants, such as particulate matter 2.5 (PM2.5) and ozone (O3). Such exposure usually does not exclude these two types of pollutants and their harmful effects could be additive or synergistic. O3 is a highly oxidizing gas that reacts with the cellular environment just as PM2.5, triggering nitrooxidative damage. Once nitrooxidative stress overcomes the endogenous antioxidant system, an acute neuroinflammatory process is generated, and once it becomes chronic, it favors the formation of neurodegenerative disease markers. The presence of these markers becomes potentially dangerous in people who have a genetic predisposition and are at a higher risk of developing neurodegenerative diseases such as Alzheimer's and Parkinson's. Our experimental approach for nitrooxidative damage and neuroinflammation caused by air pollutants has focused on the exposure of rats to O3 in an isolated chamber. The hippocampus is the most studied brain structure because of its neuronal connectivity network with the olfactory epithelium, its weak antioxidant defense, and its fundamental roll in cognitive processes. However, other brain structures may exhibit a different degree of damage upon exposure to O3 and PM2.5, making their involvement an important factor in developing other CNS diseases. The age spectrum for augmented sensibility to air pollutants seems to mostly affect the pre-postnatal (autism spectrum) period and the elderly (neurodegenerative). Thus, a new approach could be the estimation of the damage caused by PM2.5 and O3 through a controlled exposure paradigm to determine the extent of damage caused by both pollutants.

Curcumin Modifies the Activity of Plasmatic Antioxidant Enzymes and the Hippocampal Oxidative Profile in Rats upon Acute and Chronic Exposure to Ozone.

Ozone (O3) is an oxidating tropospheric pollutant. When O3 interacts with biological substrates, reactive oxygen and nitrogen species (RONS) are formed. Severe oxidative damage exhausts the endogenous antioxidant system, which leads to the decreased activity of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD). Curcumin (CUR) is a natural polyphenol with well-documented antioxidant and anti-inflammatory properties. The aim of this work is to evaluate the effects of curcumin on CAT, GPx, and SOD activity and the inhibition of oxidative damage after the acute and chronic exposure to O3. Fifty male Wistar rats were divided into five experimental groups: the intact control, CUR-fed control, exposed-to-O3 control, CUR-fed (preventive), and CUR-fed (therapeutic) groups. These two last groups received a CUR-supplemented diet while exposed to O3. These experiments were performed during acute- and chronic-exposure phases. In the preventive and therapeutic groups, the activity of plasma CAT, GPx, and SOD was increased during both exposure phases, with slight differences; concomitantly, lipid peroxidation and protein carbonylation were inhibited. For this reason, we propose that CUR could be used to enhance the activity of the antioxidant system and to diminish the oxidative damage caused by exposure to O3.

Curcumin Decreases Hippocampal Neurodegeneration and Nitro-Oxidative Damage to Plasma Proteins and Lipids Caused by Short-Term Exposure to Ozone.

Neurodegeneration is the consequence of harmful events affecting the nervous system that lead to neuronal death. Toxic substances, including air pollutants, are capable of inducing neurodegeneration. Ozone (O3) is the most oxidative toxic pollutant. O3 reacts with cellular components and forms reactive oxygen and nitrogen species, triggering nitro-oxidative damage during short-term exposure. Curcumin (CUR) is a natural phenolic molecule bearing well-documented antioxidant and anti-inflammatory biological activities in diverse experimental models. The aim of this work was to evaluate the effect of preventive dietary administration of CUR against hippocampal neurodegeneration and nitro-oxidative damage caused by short-term exposure to O3. Eighty Wistar male rats were distributed into four experimental groups, twenty rats each: intact control; CUR dietary supplementation without O3 exposure; exposure to 0.7 ppm of O3; and exposed to O3 with CUR dietary supplementation. Five rats from each group were sacrificed at 1, 2, 4, and 8 h of exposure. The CUR dose was 5.6 mg/kg and adjusted according to food consumption. CUR significantly decreased oxidative damage to plasma lipids and proteins, as well as neurodegeneration in CA1 and CA3 hippocampal regions. Concluding, CUR proved effective protection in decreasing neurodegeneration in the hippocampus and prevented systemic oxidative damage.

Curcumin Exerted Neuroprotection against Ozone-Induced Oxidative Damage and Decreased NF-κB Activation in Rat Hippocampus and Serum Levels of Inflammatory Cytokines.

Ozone is a harmful tropospheric pollutant, causing the formation of reactive oxygen and nitrogen species that lead to oxidative damage in living beings. NF-κB can be activated in response to oxidative damage, inducing an inflammatory response. Nowadays, there are no reliable results that consolidate the use of antioxidants to protect from damage caused by ozone, particularly in highly polluted cities. Curcumin has a strong antioxidant activity and is a potent inhibitor of NF-κB activation with no side effects. The aim of this study is to evaluate the effect of curcumin in preventive and therapeutic approaches against oxidative damage, NF-κB activation, and the rise in serum levels of IL-1ß and TNF-α induced by acute and chronic exposure to ozone in rat hippocampus. One hundred male Wistar rats were distributed into five groups; the intact control, curcumin-fed control, the ozone-exposed group, and the preventive and therapeutic groups. These last two groups were exposed to ozone and received food supplemented with curcumin. Lipid peroxidation was determined by spectrophotometry, and protein oxidation was evaluated by immunodetection of carbonylated proteins and densitometry analysis. Activation of NF-κB was assessed by electrophoretic mobility shift assay (EMSA), and inflammatory cytokines (IL-1ß and TNF-α) were determined by ELISA. Curcumin decreased NF-κB activation and serum levels of inflammatory cytokines as well as protein and lipid oxidation, in both therapeutic and preventive approaches. Curcumin has proven to be a phytodrug against the damage caused by the environmental exposure to ozone.

Curcumin alters the cytoskeleton and microtubule organization on trophozoites of Giardia lamblia.

Giardia lamblia is a worldwide protozoan responsible for a significant number of intestinal infections. There are several drugs for the treatment of giardiasis, but they often cause side effects. Curcumin, a component of turmeric, has antigiardial activity; however, the molecular target and mechanism of antiproliferative activity are not clear. The effects of curcumin on cellular microtubules have been widely investigated. Since tubulin is the most abundant protein in the cytoskeleton of Giardia, to elucidate whether curcumin has activity against the microtubules of this parasite, we treated trophozoites with curcumin and the cells were analyzed by scanning electron microscopy and confocal microscopy. Curcumin inhibited Giardia proliferation and adhesion in a time-concentration-dependent mode. The higher inhibitory concentrations of curcumin (3 and 15µM) disrupted the cytoskeletal structures of trophozoites; the damage was evident on the ventral disk, flagella and in the caudal region, also the membrane was affected. The immunofluorescence images showed altered distribution of tubulin staining on ventral disk and flagella. Additionally, we found that curcumin caused a clear reduction of tubulin expression. By docking analysis and molecular dynamics we showed that curcumin has a high probability to bind at the interface of the tubulin dimer close to the vinblastine binding site. All the data presented indicate that curcumin may inhibit Giardia proliferation by perturbing microtubules.

Inactivation of GABAA receptor is related to heat shock stress response in organism model Caenorhabditis elegans.

The mechanisms underlying oxidative stress (OS) resistance are not completely clear. Caenorhabditis elegans (C. elegans) is a good organism model to study OS because it displays stress responses similar to those in mammals. Among these mechanisms, the insulin/IGF-1 signaling (IIS) pathway is thought to affect GABAergic neurotransmission. The aim of this study was to determine the influence of heat shock stress (HS) on GABAergic activity in C. elegans. For this purpose, we tested the effect of exposure to picrotoxin (PTX), gamma-aminobutyric acid (GABA), hydrogen peroxide, and HS on the occurrence of a shrinking response (SR) after nose touch stimulus in N2 (WT) worms. Moreover, the effect of HS on the expression of UNC-49 (GABAA receptor ortholog) in the EG1653 strain and the effect of GABA and PTX exposure on HSP-16.2 expression in the TJ375 strain were analyzed. PTX 1 mM- or H2O2 0.7 mM-exposed worms displayed a SR in about 80 % of trials. GABA exposure did not cause a SR. HS prompted the occurrence of a SR as did PTX 1 mM or H2O2 0.7 mM exposure. In addition, HS increased UNC-49 expression, and PTX augmented HSP-16.2 expression. Thus, the results of the present study suggest that oxidative stress, through either H2O2 exposure or application of heat shock, inactivates the GABAergic system, which subsequently would affect the oxidative stress response, perhaps by enhancing the activity of transcription factors DAF-16 and HSF-1, both regulated by the IIS pathway and related to hsp-16.2 expression.

Changes in the content of GFAP in the rat brain during pregnancy and the beginning of lactation.

Several changes in brain function, including learning and memory, have been reported during pregnancy but the molecular mechanisms involved in these changes are unknown. Due to the fundamental role of glial cells in brain activity, we analyzed the content of glial fibrillary acidic protein (GFAP) in the hippocampus, frontal cortex, preoptic area, hypothalamus and cerebellum of the rat on days 2, 14, 18, and 21 of pregnancy and on day 2 of lactation by Western blot. A differential expression pattern of GFAP was found in the brain during pregnancy and the beginning of lactation. GFAP content was increased in the hippocampus throughout pregnancy, whereas a decrease was observed in cerebellum. GFAP content was increased in the frontal cortex and hypothalamus on days 14 and 18, respectively, with a decrease in the following days of pregnancy in both regions. In preoptic area a decrease in GFAP content was observed on day 14 with an increase on days 18 and 21. In the frontal cortex and cerebellum, GFAP content was increased on day 2 of lactation, while it was maintained as on day 21 of pregnancy in the other regions. Our data suggest a differential expression pattern of GFAP in the rat brain during pregnancy and the beginning of lactation that should be associated with changes in brain function during these reproductive stages.

TRESK-like potassium channels in leukemic T cells.

In this study, we present patch-clamp characterization of the background potassium current in human lymphoma (Jurkat cells), generated by voltage-independent 16 pS channels with a high ( approximately 100-fold) K+/Na+ selectivity. Depending on the background K+ channels density, from few per cell up to approximately 1 open channel per microm2, resting membrane potential was in the range of -40 to -83 mV, approaching E (K) = -88 mV. The background K+ channels were insensitive to margotoxin (3 nM), apamine (3 nM), and clotrimazole (1 microM), high-affinity blockers of the lymphocyte Kv1.3, SKCa2, and IKCa1 channels. The current depended weakly on external pH. Arachidonic acid (20 microM) and Hg2+ (0.3-10 microM) suppressed background K+ current in Jurkat cells by 75-90%. Background K+ current was weakly sensitive to TEA+ (IC50 = 14 mM), and was efficiently suppressed by externally applied bupivacaine (IC50 = 5 microM), quinine (IC50 = 16 microM), and Ba2+ (2 mM). Our data, in particular strong inhibition by mercuric ions, suggest that background K+ currents expressed in Jurkat cells are mediated by TWIK-related spinal cord K+ (TRESK) channels belonging to the double-pore domain K+ channel family. The presence of human TRESK in the membrane protein fraction was confirmed by Western blot analysis.

Castración no quirúrgica por inyección intratesticular con una preparación de epinefrina-propilenglicol en lechones / Non-chirurgical castration with an intratesticular injection of epinephrine-propyleclycol in piglets

Se evaluó un método de castración no quirúrgico por inyección intratesticular en lechones de 21 días de edad. Cinco grupos experimentales fueron tratados con diferentes mezclas. Un grupo fue inyectado con formaldehido, xilocaína, epinefrina y propilenglicol (FXEP), otro con xilocaína y propolenglicol (XP), otro con epinefrina y propilenglicol (EP), otro con propilenglicol (P) y otro con formaldehido en solución amortiguadora de fosfatos 0.1 M (F). Se inyectó 1.5 ml de cada mezcla experimental en cada testículo de los lechones según su grupo. El tratamiento EP luego de 30 Días causó necrosis completa, a 90 y 180 días postratamiento se observó fibrosis, lo cual revela probablemente atrofia irreversible de ambos testículos. Asimismo, dichoo tratamiento produjo severa reducción del peso testicular, sin embargo, no se observaron efectos colaterales indeseables. El tratamiento no afectó el peso somático. En los otros grupos experimentales no se obtuvieron resultados satisfactorios sobre la atrofia y reducción de peso testicular. La preparación experimental no es costosa, la técnica de inyección es sencilla y facíl de realizar, y podría ser un modelo rápido y efectivo de castración no quirúrgica. Sin embargo, se encuentra aún en fase experimental.