Oleic acid reduces oxidative stress in rat brain induced by some anticancer drugs.

Oleic acid (OA) is a monounsaturated compound with many health-benefitting properties such as obesity prevention, increased insulin sensitivity, antihypertensive and immune-boosting properties, etc. The aim of this study was to analyze the effect of oleic acid (OA) and some anticancer drugs against oxidative damage induced by nitropropionic acid (NPA) in rat brain. Six groups of Wistar rats were treated as follows: Group 1, (control); group 2, OA; group 3, NPA + OA; group 4, cyclophosphamide (CPP) + OA; group 5, daunorubicin (DRB) + OA; and group 6, dexrazoxane (DXZ) + OA. All compounds were administered intraperitoneally route, every 24 h for 5 days. Their brains were extracted to measure lipoperoxidation (TBARS), H2O2, Ca+2, Mg+2 ATPase activity, glutathione (GSH) and dopamine. Glucose, hemoglobin and triglycerides were measured in blood. In cortex GSH increased in all groups, except in group 2, the group 4 showed the highest increase of this biomarker. TBARS decrease, and dopamine increase in all regions of groups 4, 5 and 6. H2O2 increased only in cerebellum/medulla oblongata of group 5 and 6. ATPase expression decreased in striatum of group 4. Glucose increased in group 6, and hemoglobin increased in groups 4 and 5. These results suggest that the increase of dopamine and the antioxidant effect of oleic acid administration during treatment with oncologic agents could result in less brain injury.

N-Acetylcysteine Attenuates Cisplatin Toxicity in the Cerebrum and Lung of Young Rats with Artificially Induced Protein Deficiency.

Neurotoxicity is a major obstacle in the effectiveness of Cisplatin in cancer chemotherapy. In this process, oxidative stress and inflammation are considered to be the main mechanisms involved in brain and lung toxicity. The aim of the present work was to study the influence of the amount of protein on some oxidative parameters in the brain and lungs of rats treated with Cisplatin (CP) and N-Acetylcysteine (NAC) as neuroprotectors. Four groups of Wistar rats, each containing six animals, were fed with a protein diet at 7% for 15 days. Thereafter, the groups were given either a unique dose of CP® 5 mg/kg or NAC® 5 mg/kg as follows: group 1 (control), NaCl 0.9% vehicle; group 2, CP; group 3, NAC; and group 4, NAC + CP. The animals were sacrificed immediately after the treatments. Blood samples were collected upon sacrifice and used to measure blood triglycerides and glucose. The brain and lungs of each animal were obtained and used to assay lipid peroxidation (TBARS), glutathione (GSH), serotonin metabolite (5-HIAA), catalase, and the activity of Ca+2, and Mg+2 ATPase using validated methods. TBARS, H2O2, and GSH were found to be significantly decreased in the cortex and cerebellum/medulla oblongata of the groups treated with CP and NAC. The total ATPase showed a significant increase in the lung and cerebellum/medulla oblongata, while 5-HIAA showed the same tendency in the cortex of the same group of animals. The increase in 5-HIAA and ATPase during NAC and CP administration resulted in brain protection. This effect could be even more powerful when membrane fluidity is increased, thus proving the efficacy of combined NAC and CP drug therapy, which appears to be a promising strategy for future chemotherapy in malnourished patients.

Habilitation of Executive Functions in Pediatric Congenital Heart Disease Patients through LEGO®-Based Therapy: A Quasi-Experimental Study.

Congenital heart disease is defined as an abnormality in the cardiocirculatory structure or function. Various studies have shown that patients with this condition may present cognitive deficits. To compensate for this, several therapeutic strategies have been developed, among them, the LEGO® Education sets, which use the pedagogic enginery to modify cognitive function by didactic material based on mechanics and robotics principles. Accordingly, the goal of this study was to evaluate the effect of cognitive habilitation by using LEGO®-based therapy in pediatric congenital heart disease patients. This was a quasi-experimental study; eligible patients were identified, and their general data were obtained. In the treatment group, an initial evaluation with the neuropsychological BANFE-2 test was applied; then, once a week, the interventions were performed, with a final test at the end of the interventions. In the control group, after the initial evaluation, a second appointment was scheduled for the final evaluation. Our results show that >50% of children presented cognitive impairment; nevertheless, there was an overall improvement in treatment patients, showing a significant increase in BANFE scores in areas related to executive functions. LEGO®-based therapy may be useful to improve cognitive abilities; however, future research should be performed to strengthen the data.

Effect of cerebrolysin on dopaminergic neurodegeneration of rat with oxidative stress induced by 3-nitropropionic acid.

The study tested the hypothesis that cerebrolysin protects the brain from free radicals in rats treated with 3-nitropropionic acid (3-NPA). To address this hypothesis, the levels of dopamine (DA) and some oxidative stress biomarkers were measured after administration of 3-NPA. Young male Fischer rats were treated for three days with cerebrolysin, 3-NPA or both substances. Their brains were extracted, and DA, lipid peroxidation (LP), glutathione (GSH), calcium, and H2O2 were measured using validated methods. In the cortex, hemispheres and cerebellum/medulla oblongata of the group treated with cerebrolysin and 3-NPA, the levels of DA and LP decreased. In addition, calcium and H2O2 levels decreased in the hemispheres of the same group, while GSH increased in cortex. The increased dopamine metabolism due to the administration of cerebrolysin led to increased formation of radical species and oxidative stress, especially when free radicals were generated by 3-NPA.

Comparative effects of catechin, epicatechin and N-Ω-nitroarginine on quinolinic acid-induced oxidative stress in rat striatum slices.

UNLABELLED: The aim of this work was to compare the effects of catechin (CAT), epicatechin (EPI) and N-ω-l-nitroarginine (L-NARG) on different endpoints of oxidative stress induced by quinolinic acid (QUIN) in a simple tissue preparation, rat striatal slices - with particular emphasis in the glutathione system - in order to provide revealing information on the antioxidant efficacy of these agents in an excitotoxic model. METHODS: Rat striatal slices were incubated for 1h in the presence of 100 µM QUIN and/or 85 µM CAT or EPI, or 100 µM L-NARG. Lipid peroxidation (LP) and the levels of reduced and oxidized glutathione (GSH and GSSG) were determined. RESULTS: The three agents tested completely blocked the QUIN-induced lipid peroxidation and recovered the QUIN-induced altered GSH/GSSG balance. No statistical differences were detected among the protective effects exerted by these antioxidants, suggesting similar efficacy and common antioxidant mechanisms. The antioxidant properties exhibited by these molecules on the excitotoxic model tested herein support an active role of glutathione and prompt their use as therapeutic tools in models of neurodegenerative disorders.

Effect of mosquito mats (pyrethroid-based) vapor inhalation on rat brain cytochrome P450s.

The effect of transfluthrin (TF) or D-allethrin (DA) pyrethroid (PYR) vapors, often contained as main ingredients in two commercially available mosquito repellent mats, on cytochrome P450 (CYP) enzymes of rat brain and liver was assessed. Immunodetection of CYP2E1 and CYP3A2 proteins revealed their induction in cerebrum and cerebellum, but not in liver microsomes of rats exposed by inhalation to TF or DA. This overexpression of proteins correlated with an increase of their catalytic activities. The specifically increased expression of CYP isoenzymes, due to PYR exposure in the rat brain, could perturb the normal metabolism of endogenous and xenobiotic compounds and leads to increased risks of neurotoxicity by bioactivation, lipid peroxidation and DNA damage.

The administration of food supplemented with cocoa powder during nutritional recovery reduces damage caused by oxidative stress in rat brain.

Malnutrition contributes to the development of oxidative damage in the central nervous system. The selective administration of nutrients tends to show positive results in individuals who have suffered from malnutrition. To determine the effect of the administration of cocoa powder on the peroxidation of lipids and glutathione level during the nutritional recovery in brain, rats of 21 days old were subjected to a protocol that resembles malnutrition (MN) by feeding them with 60% of the daily food consumption of the control group (WN) and later to nutritional recovery with regular rodent feed (RFR) or added with cocoa (10 g of cocoa powder/kg of regular rodent feed) (CCR). Animals fed with regular rodent food showed significant reduction in brain glutathione: RFR (84.18 ± 6.38 ng/mg protein) vs. CCR (210.61 ± 50.10 ng/mg protein) and WN (186.55 ± 33.18 ng/mg protein), but with similar level to that of MN (92.12 ± 15.60 ng/mg protein). On the contrary, lipid peroxidation in RFR-fed animals increased RFR (1.32 ± 0.2 µM malondialdehyde/g of tissue), CCR (0.86 ± 0.07 µM malondialdehyde/g of tissue), WN (0.89 ± 0.09 µM malondialdehyde/g of tissue), but their thiobarbituric acid reactive substances concentration is similar to that of MN group (1.50 ± 0.2 µM malondialdehyde/g of tissue). Consumption of cocoa powder as a source of antioxidants favors the restoration of the concentration of glutathione and reduces the damage caused by oxidative stress during nutritional recovery in rat brain.

Levels of 5-hydroxyindol acetic acid and lipid peroxidation in brain after administration of marijuana and nalbuphine in male and female rat.

We analyzed the effect of marijuana and nalbuphine on levels of 5-hydroxyindol acetic acid and lipid peroxidation in rat brain. Single and repeated dosages of 250 mg/kg marijuana extract or 10 mg/kg nalbuphine were administered to male and female Wistar rats. Animals were sacrificed and brains were obtained to measure the content of 5-hydroxyindol acetic acid, reduced glutathione, thiobarbituric acid reactive substances, total ATPase and Na+/K+ ATPase activities. There was an increase in thiobarbituric acid reactive substances, total ATPase and Na+/K+ ATPase activity in the animals that received a single dose of marijuana and nalbuphine (p=0.001), with a notable decrease in glutathione and 5-hydroxyindol acetic acid levels (p=0.001). Both marijuana and nalbuphine increased levels of oxidative damage biomarkers in rat brain and decreased glutathione and 5-hydroxyindol acetic acid levels which could provoke changes in cellular and biochemical regulations and serotonergic activity in either male or female rats.

Neuro-protective effects of carbamazepine on sleep patterns and head and body shakes in kainic acid-treated rats.

UNLABELLED: The aim of this work was to analyze the effect of carbamazepine (CBZ) on sleep patterns and on "head and body shakes" and to determine the role of serotonin (5-HT) in a model of kainic-induced seizures. Thirty male Wistar rats (280-300 g) were used for polygraphic sleep recording. After a basal recording, the rats were allocated into three groups: kainic acid-treated animals (KA; 10 mg/kg; n=10), carbamazepine-treated animals (CBZ; 30 mg/kg; n=10) and animals injected with KA 30 min after pretreatment with CBZ (CBZ+KA; n=10). Polygraphic recordings were performed for 10 h for 3 days, with the exception of the CBZ group, which were observed for 1 day. In order to measure the head and body shakes that occurred over that time, a behavioral assessment was performed in two additional groups of KA (n=10) and CBZ+KA (n=10) animals. After 10 h of behavioral assessment, the rats were sacrificed, and the levels of 5-HT and 5-hydroxy-indol-acetic acid (5-HIAA) were analyzed. We compared these findings with the results from a group of rats without pharmacological intervention (n=10). All of the recordings were performed from 08:00 to 18:00 h. DATA ANALYSIS: the electrographic parameters, head and body shake counting and monoamine concentrations were analyzed by an ANOVA test. Differences of *p < or = 0.01 and **p < or = 0.001 were considered statistically significant. Our results showed that CBZ exerted a protective effect on sleep pattern alterations induced by KA, which when administered alone caused a complete inhibition of sleep for the first 10 h after administration. Although there was a reduction in the amount of sleep after the administration of KA in CBZ-pretreated animals, sleep inhibition was incomplete. In addition, CBZ decreased the frequency of head and body shakes by 60% as compared to KA. The 5-HT and 5-HIAA levels in the pons were increased in the KA and KA+CBZ groups. Our conclusion is that in addition to decreasing seizure intensity, CBZ facilitates the partial recovery of sleep. These results suggest that CBZ provides neuro-protective effects on sleep and against seizures.

Kainic acid does not modify the oral pharmacokinetics of carbamazepine in rats.

Carbamazepine (CBZ) is a widely used antiepileptic agent that frequently interacts with other drugs. Recently, it has been reported that CBZ is able to modify the disturbed sleep patterns induced by kainic acid in epileptics. As a pharmacokinetic-pharmacodynamic characterization in the same animal is not possible due to the stress induced by blood sampling, it is important to establish if kainic acid is able to modify the pharmacokinetics of CBZ. Two groups of seven rats were used in this study. Animals received an oral dose of 50 mg/kg of CBZ alone or with 10 mg/kg of kainic acid. Blood samples (0.1 mL) were obtained at selected times for 12 hr and stored frozen until analyzed by HPLC. Pharmacokinetic parameters were: Cmax 6.51 +/- 1.32 and 6.63 +/- 0.95 microg/mL, tmax 3.55 +/- 0.98 and 1.82 +/- 0.59 hr, AUC 66.61 +/- 28.16 and 73.54 +/- 15.35 microg x h/mL and t1/2 7.16 +/- 2.55 and 5.80 +/- 1.37 hr. No statistically significant difference was observed in any parameter indicating that kainic acid is not able to modify oral pharmacokinetics of CBZ and pharmacokinetic-pharmacodynamic studies may be carried out using two groups of animals, one for the pharmacodynamics and another for the pharmacokinetic evaluation.

Tissue-specific induction of the carcinogen-inducible cytochrome P450 isoforms in the gastrointestinal tract.

Gastrointestinal tissues are directly exposed to dietary xenobiotics. In spite of this, modulation of cytochrome P450 (CYP) enzymes in the gastrointestinal tract is not well established. CYP induction could facilitate transformation of chemical agents to potentially toxic or carcinogenic metabolites. This might also determine drug efficacy, burden of foreign chemicals on tissues or bioavailability of certain therapeutic agents. In order to assess the induction of the CYP subfamilies 1A1/2, 2B1/2, 2E1 and 3A2 in the gastrointestinal tract, male Wistar rats were treated with phenobarbital/ß-naphthoflavone (PB/NF), cyclohexanol/albendazole (CH/ABZ) or toluene (TL). Microsomal fractions were prepared from tissue samples of the esophagus, the stomach, the duodenum, the colon and the liver. Western blot and enzymatic activity analyses revealed an increase in the expression and activity of CYP1A1/2 and CYP3A2 isoenzymes in the esophageal, duodenal and colonic microsomes from animals treated with PB/NF. CYP1A1/2 and CYP3A2 were induced in hepatic and duodenum microsomes by treatment with CH/ABZ. Our results demonstrate differential induction of CYP along the gastrointestinal tract by known CYP hepatic inducers, being the treatment with PB/NF the best induction system of the CYPs.

Effect of nutritional status and ozone exposure on rat brain serotonin.

BACKGROUND: Ozone is an environmental pollutant that has widely documented deleterious effects on exposed organisms. In Mexico City, this pollutant frequently reaches concentrations that surpass safe health limits. In addition, it has been reported that the prevalence of malnutrition remains high in our childhood population. This experiment was carried out to determine whether malnutrition is a factor contributing to an increase in the risk of damage associated with ozone exposure. METHODS: Using an experimental animal model, 21-day-old rats fed normally or with induced malnutrition were subchronically exposed to 0.5 ppm of ozone or fresh air, respectively, for 30 days. At the end of this period and using HPLC, serotonin concentrations were measured in four areas of the brain: cortex, hemispheres, cerebellum, and medulla oblongata. RESULTS: Malnourished animals had a significant weight deficit beginning at 28 days with respect to well-fed animals. Among the well-fed animals, this phenomenon is seen at 35 days in exposed and non-exposed animals. In the four regions of the brain, malnourished animals show low serotonin concentrations with respect to well-nourished animals. In the cerebellum, there was an interaction between the nutritional factor and ozone exposure, while in the medulla oblongata both factors acted independently. CONCLUSIONS: Our results suggest a multiplicative effect from the nutritional factor and ozone exposure in the changes observed concerning serotonergic metabolism.

Estudio in vitro de tres antiandrógenos empleados en la actualidad en enfermedades andrógenodependientes / In vitro assay of three antiandrogens presently used in the treatment of androgen dependent diseases

Objetivo: Analizar el efecto in vitro del acetato de ciproterona, finasteride y flutamida, sobre la enzima 5Ó-reductasa, principal indicador bioquímico responsable del potente efecto andrógenico de la tetosterona, al convertirla en dihidrotestosterona. Material y Métodos: Se midio la actividad de la enzima 5Ó-reductasa en la próstata de ratas de macho adultos, utilizando concentraciones de 20 a 500µM de cada antiandrógeno. Resultados: El análisis estadístico muestra que la flutamina presenta mejor actividad antiandrogénica a medida que se incrementa su concentración, mientras que en el acetato de ciproterona y el finasteride, el efecto antiandrogénico fue menor a diferentes concentraciones (p<0.05); probablemente por una mayor velocidad de disociación de estos compuestos con su receptor

Effects of toluene exposure on ATPase activity in synaptosomal membranes of rat brain, "in vivo" and "in vitro" studies

Se presenta un trabajo de investigación en el cual se midió la actividad de la enzima Na+K+-ATPasa en la fracción sinaptosomal en cerebro de ratas de la Cepa Wistar expuestas en forma aguda (una exposición) y crónica (30 días consecutivos) a vapores de tolueno, (concentración de 15000 ppm en aire, durante 15 min.) en contraste con un grupo de ratas "control" expuestas al aire libre de tolueno, (estudio in vivo). Los estudios in vitro consistieron en la incubación de la fracción sinaptosomal de cerebro de rata en tubos cerrados conteniendo en el medio reactivo de tolueno a la concentración de 10mM. El cáculo de las constantes de Michaelis-Menten (Km y Vmax) fueron evaluadas en los estudios cinéticos de la enzima en las membranas sinaptosomales. Las ratas tanto de 50 como de 120 días de edad, que fueron expuestas en forma crónica a vapores de tolueno mostraron una reducción de la actividad entre 45 y 56 por ciento con respecto a la actividad del grupo control, siendo estadísticamente significativa (p<0.05). No habiendo diferencias en las ratas expuestas a tolueno en forma aguda. En los experimentos in vitro, también mostraron reducción en la actividad de la enzima podría ser un indicador de los efectos acumulativos de las propiedades físico-químicas del tolueno sobre las membranas biológicas