The inhibitory effect of Cannabis Sativa L. and Morus nigra L. against lipid peroxidation in goat liver and brain homogenates / O efeito inibitório de Cannabis Sativa L. e Morus nigra L. contra a peroxidação lipídica em homogenatos de fígado e cérebro de cabra

The present study was aimed to evaluate the antioxidant potential and inhibitory effect of Cannabis sativa and Morus nigra against lipid peroxidation in goat brain and liver homogenates. The formation of free radicals, highly reactive oxygen species (ROS) and reactive nitrogen species (RNS) is a normal metabolic process for cellular signaling and countering the antigens. However, they may cause serious damage if they produced at amplified tolls. In addition, metabolic disorders also serve as sources of these reactive species. Although the issue can be addressed through supplements and other phytochemicals. In this study, two plant species were evaluated for their biological potential by employing a spectrum of antioxidant assays. The antioxidant activity was performed by lipid peroxidation assay. The water extract prepared from leaves of Cannabis sativa and Morus nigra showed significant (P<0.05) inhibition as compared to control i.e., 522.6±0.06 and 659.97±0.03 µg/mL against iron-induced lipid peroxidation in goat brain homogenate while the inhibitions were 273.54±0.04 and 309.18±0.05 µg/mL against nitroprusside induced lipid peroxidation of the brain. The iron and nitroprusside induced lipid peroxidation was also significantly inhibited by leaf extracts of Cannabis sativa and Morus nigra in liver homogenates such as 230.63±0.52 and 326.91±0.01 µg/mL (iron-induced) while 300.47±0.07 and 300.47±0.07 µg/mL (nitroprusside induced), respectively. The extracts of Cannabis sativa extract showed promising activity (96.04±0.060%) against DPPH radicals while Morus nigra showed a moderate activity (34.11±0.120%). The results suggest that different accessions of Cannabis sativa and Morus nigra are a potential source of antioxidants and have a therapeutic effect against disease induced by oxidative stress and hence can be used for novel drug discovery and development.

O presente estudo teve como objetivo avaliar o potencial antioxidante e o efeito inibitório de Cannabis sativa e Morus nigra contra a peroxidação lipídica em homogenatos de cérebro e fígado de cabras. A formação de radicais livres, espécies altamente reativas de oxigênio (ROS) e espécies reativas de nitrogênio (RNS), é um processo metabólico normal para sinalização celular e combate aos antígenos. No entanto, eles podem causar sérios danos se forem produzidos em portagens ampliadas. Além disso, distúrbios metabólicos também servem como fontes dessas espécies reativas, embora o problema possa ser resolvido por meio de suplementos e outros fitoquímicos. Neste estudo, duas espécies de plantas foram avaliadas quanto ao seu potencial biológico, empregando um espectro de ensaios antioxidantes. A atividade antioxidante foi realizada por ensaio de peroxidação lipídica. O extrato de água preparado a partir de folhas de Cannabis sativa e Morus nigra mostrou inibição significativa (P < 0,05) em comparação com o controle, ou seja, 522,6 ± 0,06 e 659,97 ± 0,03 µg / mL contra peroxidação lipídica induzida por ferro em homogenato de cérebro de cabra, enquanto as inibições foram 273,54 ± 0,04 e 309,18 ± 0,05 µg / mL contra a peroxidação lipídica do cérebro induzida por nitroprussiato. A peroxidação lipídica induzida por ferro e nitroprussiato também foi significativamente inibida por extratos de folhas de Cannabis sativa e Morus nigra em homogenatos de fígado, como 230,63 ± 0,52 e 326,91 ± 0,01 µg / mL (induzida por ferro), enquanto 300,47 ± 0,07 e 300,47 ± 0,07 µg / mL (induzida por nitroprussiato), respectivamente. Os extratos do extrato de Cannabis sativa apresentaram atividade promissora (96,04 ± 0,060%) contra os radicais DPPH enquanto Morus nigra apresentou atividade moderada (34,11 ± 0,120%). Os resultados sugerem que diferentes acessos de Cannabis sativa e Morus nigra são uma fonte potencial de antioxidantes e têm efeito terapêutico [...].

CeRebrUm and CardIac Protection with ALlopurinol in Neonates with Critical Congenital Heart Disease Requiring Cardiac Surgery with Cardiopulmonary Bypass (CRUCIAL): study protocol of a phase III, randomized, quadruple-blinded, placebo-controlled, Dutch multicenter trial.

BACKGROUND: Neonates with critical congenital heart disease (CCHD) undergoing cardiac surgery with cardiopulmonary bypass (CPB) are at risk of brain injury that may result in adverse neurodevelopment. To date, no therapy is available to improve long-term neurodevelopmental outcomes of CCHD neonates. Allopurinol, a xanthine oxidase inhibitor, prevents the formation of reactive oxygen and nitrogen species, thereby limiting cell damage during reperfusion and reoxygenation to the brain and heart. Animal and neonatal studies suggest that allopurinol reduces hypoxic-ischemic brain injury and is cardioprotective and safe. This trial aims to test the hypothesis that allopurinol administration in CCHD neonates will result in a 20% reduction in moderate to severe ischemic and hemorrhagic brain injury. METHODS: This is a phase III, randomized, quadruple-blinded, placebo-controlled, multicenter trial. Neonates with a prenatal or postnatal CCHD diagnosis requiring cardiac surgery with CPB in the first 4 weeks after birth are eligible to participate. Allopurinol or mannitol-placebo will be administered intravenously in 2 doses early postnatally in neonates diagnosed antenatally and 3 doses perioperatively of 20 mg/kg each in all neonates. The primary outcome is a composite endpoint of moderate/severe ischemic or hemorrhagic brain injury on early postoperative MRI, being too unstable for postoperative MRI, or mortality within 1 month following CPB. A total of 236 patients (n = 188 with prenatal diagnosis) is required to demonstrate a reduction of the primary outcome incidence by 20% in the prenatal group and by 9% in the postnatal group (power 80%; overall type 1 error controlled at 5%, two-sided), including 1 interim analysis at n = 118 (n = 94 with prenatal diagnosis) with the option to stop early for efficacy. Secondary outcomes include preoperative and postoperative brain injury severity, white matter injury volume (MRI), and cardiac function (echocardiography); postnatal and postoperative seizure activity (aEEG) and regional cerebral oxygen saturation (NIRS); neurodevelopment at 3 months (general movements); motor, cognitive, and language development and quality of life at 24 months; and safety and cost-effectiveness of allopurinol. DISCUSSION: This trial will investigate whether allopurinol administered directly after birth and around cardiac surgery reduces moderate/severe ischemic and hemorrhagic brain injury and improves cardiac function and neurodevelopmental outcome in CCHD neonates. TRIAL REGISTRATION: EudraCT 2017-004596-31. Registered on November 14, 2017. ClinicalTrials.gov NCT04217421. Registered on January 3, 2020.

Excessive manganese alters serum biochemical indices, induces histopathological alterations, and activates apoptosis in liver and cerebrum of Jianzhou Da'er goat (Capra hircus).

The present study aimed to explore the toxic effects of excessive dietary Mn in livers and cerebrums of Jianzhou Da'er goat (Capra hircus). Three-month old goats were assigned into three groups: control group, fed on basal diet; Mn I group, fed on the basal diet mixed with MnCl2 (2.5 g/kg); Mn II group, fed on the basal diet mixed with MnCl2 (5 g/kg). Compared with the control group, the activities of serum alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and the concentrations of interferon-γ (IFN-γ) in Mn I and Mn II groups were significantly increased, but the concentrations of IgG in Mn I and Mn II groups were significantly decreased (p < 0.05). The activities of superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), and the concentrations of glutathione (GSH) in Mn I and Mn II groups were significantly decreased, whereas the concentrations of malondialdehyde (MDA) in Mn I and Mn II groups were significantly increased in livers and cerebrums (p < 0.05). Moreover, the hepatocytes necrosed, inflammatory cells infiltrated, chromatin concentrated, mitochondrial cristae reduced in Mn I and Mn II groups. The nerve cells necrosed, blood vessels congested, inflammatory cells infiltrated, mitochondrial electron density and mitochondrial cristae decreased, and vacuolization increased in Mn I and Mn II groups. Furthermore, the mRNA expressions of tumor necrosis factor alpha (TNF-α), tumor necrosis factor receptor type 1 (TNFR1), fas-associated protein via a death domain (FADD), Bcl2-associated X (Bax), cysteinyl aspartate specific proteinase 3, 8, 9 (Caspase-3, 8, 9) in Mn I and Mn II groups were significantly increased (p < 0.05), but the mRNA expressions of B-cell lymphoma-2 (Bcl-2) in Mn I and Mn II groups were significantly decreased (p < 0.05) in livers. The mRNA expressions of Bcl-2, Bax, Caspase-3, 9, 7, 12 in Mn I and Mn II groups were significantly increased (p < 0.05), however, the ratio of Bcl-2/Bax in Mn I and Mn II groups was significantly decreased (p < 0.05) in cerebrums. In summary, our results provided new insights for better understanding the mechanisms of Mn toxicity in Capra hircus.

Tranilast ameliorated subchronic silver nanoparticles-induced cerebral toxicity in rats: Effect on TLR4/NLRP3 and Nrf-2.

Silver nanoparticles (AgNPs) are widely applied in various aspects of life. However, recent studies reported their potential toxicity both on environment and human health. The present study aimed to unravel the underlying molecular mechanisms involved in AgNPs-induced brain toxicity. Moreover, chemopreventive effect of tranilast, an analogue of tryptophan metabolite and a mast cell membrane stabilizer was evaluated. Thirty Sprague Dawley rats were enrolled equally into Normal control group, AgNPs-intoxicated group (50 mg/kg, 3 times/week) and tranilast (300 mg/kg, 3 times/week)+AgNPs group. AgNPs administration triggered brain oxidative stress as depicted by reduced Nrf-2 expression, decreased TAC and GSH as well as upregulated brain lipid peroxidation. The apparent brain oxidative damage was accompanied by elevated levels of inflammatory cytokines (IL-1ß, IL-6 and TNF-α). Moreover, brain levels of TLR4, NLRP3 and caspase-1 were up-regulated. Additionally, histological study indicated marked cellular injury in cerebrum and cerebellum specimens. This was concomitant with elevated serum CK activity and CK-BB level. On the other hand, tanilast administration remarkably alleviated AgNPs-induced brain toxicity. The present study shed the light on implication of TLR4/NLRP3 axis and NrF2 in AgNPs-induced brain toxicity. In addition, it explored the potential protective effect of tranilast on AgNPs-induced brain injury via antioxidant and anti-inflammatory efficacies.

The possible neurobehavioral protective effects of natural antioxidant against phototoxicity attenuation of antimicrobial quinolone group in rats.

The fluoroquinolones absorb light in the 320 to 330 nm ultraviolet A (UV-A) wavelength and produce reactive oxygen species (ROS) such as superoxide anion, hydroxyl radical, and hydrogen peroxide; thus, the photodynamic generation of ROS may be the basis of phototoxicity of quinolones in human beings and animals. This study aimed to evaluate the damaging effects of UV-A radiation at different periods of exposure on rats' brains administered with ciprofloxacin. Ciprofloxacin administration in UV-A exposed animals exaggerated the brain-oxidative stress biomarkers and decreased the locomotor activity. Exposure of rats to UV-A for 60 minutes induced a significant increase of malondialdehyde (MDA), myeloperoxidase (MPO), and a decrease in the values of superoxide dismutase (SOD), glutathione (GSH) compared to a normal one; these changes were UV-A exposure time-dependent. However, the administration of vitamin C to the UV-60-treated group decreased the values of MDA, MPO, and shifted the values of SOD, GSH toward the normal values. Vitamin C, probably due to its strong antioxidant properties, could improve and partially counteract the toxic effect of UV-A on oxidative stress parameters and prevent the damage in rat's brain tissues.

A single meal has the potential to alter brain oxylipin content.

Our objective was to determine whether consumption of a single meal has the potential to alter brain oxylipin content. We examined the cerebrum of mice fed a single high-fat/high-sucrose Western meal or a low-fat/low-sucrose control meal, as well as fasted mice. We found no changes in fatty acid composition of cerebrum across the groups. The cerebral oxylipin profile of mice fed a Western meal is distinct from the profile of mice fed a low-fat/low-sucrose meal. Cerebral gene expression of cyclooxygenase 1, cyclooxygenase 2, and epoxide hydrolase 1 were elevated in Western meal-fed mice compared to low-fat/low-sucrose meal-fed mice. Mice that consumed either meal had lower gene expression of cytochrome P450, family 2, subfamily j, polypeptide 12 than fasted mice. Our data in this hypothesis-generating study indicates that the composition of a single meal has the potential to alter brain oxylipins and the gene expression of the enzymes responsible for their production.

Increased levels of hexacosanoic acid in the brain of Winstar rats: a behavioral study

Introduction: X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal metabolic disorder associated with mutations in the ATP-binding cassette sub-family D member1 (ABCD1) gene. Practically all male patients with X-ALD develop adrenocortical insufficiency during childhood and progressive myelopathy and peripheral neuropathy in adulthood. However, some male patients develop a fatal cerebral demyelinating disease named cerebral adrenoleukodystrophy. Although the exact mechanisms underlying brain damage in X-ALD are still poorly elucidated, it is known that hexacosanoic acid (C26:0) accumulation represents a hallmark in the pathogenesis of this disease. In this study, we examined whether an overload of C26:0 injected in Wistar rats was capable of causing behavioral changes in these animals. Methods: Egg lecithin in ethanol was dried under a nitrogen stream and mixed with C26:0 methyl ester. Male Wistar rats at 2-3 weeks of age were obtained from Universidade Federal do Rio Grande do Sul (UFRGS), divided into 8 groups, and submitted to an open field test. We then analyzed line crossings (locomotion and exploration), rearing (orienting and investigatory responses), grooming (anxiety manifestation), and latency to move for each animal. Results: Animals subjected to C26:0 administration presented fewer crossings and rearing episodes and a higher latency to move 45 minutes after C26:0 injection. The present work yields experimental evidence that C26:0, the main accumulated metabolite in X-ALD, can cause behavioral alterations in rats such as the impairment of locomotion and exploratory capabilities, as well as a reduction in orienting and investigatory responses. Conclusion: Although our results are preliminary, they are extremely important for future studies that investigate C26:0 accumulation and locomotor impairment in patients with X-ALD. (AU)

The interaction between P2X7Rs and T-type calcium ion channels in penicillin-induced epileptiform activity.

Limited information exists on the link between purinergic class P2X7 receptors (P2X7Rs) and calcium ion channels in epilepsy; no data has been reported regarding the interaction between P2X7Rs and T-type calcium ion channels in epilepsy. Thus, this study is an evaluation of the role that T-type calcium ion channels play in the effect of P2X7Rs on penicillin-induced epileptiform activity. In the first set of experiments, P2X7R agonist BzATP (at 25-, 50-, 100- and 200-µg doses), P2X7R antagonist A-438079 (at 5-, 10-, 20- and 40-µg doses) and T-type calcium ion channel antagonist, NNC-550396 were administered for electrophysiological analyses 30 min after penicillin injection (2.5 µl, 500 IU). In the second set of experiments, the effective doses of these substances were used for biochemical analyses. Malondialdehyde (MDA), advanced oxidation protein product (AOPP), glutathione (GSH), glutathione reductase (GR), glutathione peroxide (GPx), catalase (CAT) and superoxide dismutase (SOD) levels were measured in the cerebrum, cerebellum and brainstem of rats. BzATP (100 µg, icv) increased the mean frequency of epileptiform activity, whereas A-438079 (40 µg, icv) and NNC-550396 (30 µg, ic) reduced it. Both A-438079 and NNC-550396 reversed BzATP's proconvulsant action. BzATP increased lipid peroxidation and protein oxidation; it also altered other antioxidant enzymes measured in this study, which were all then reversed via A-438079 and NNC-550396, at least in the cerebrum. The electrophysiological and biochemical analysis of present study suggest that P2X7Rs and its interaction with T-type calcium ion channels play an important role in the experimental model of epilepsy.

Umbelliferone prevents oxidative stress, inflammation and hematological alterations, and modulates glutamate-nitric oxide-cGMP signaling in hyperammonemic rats.

Hepatic encephalopathy (HE) is a serious neuropsychiatric complication that occurs as a result of liver failure. Umbelliferone (UMB; 7-hydroxycoumarin) is a natural product with proven hepatoprotective activity; however, nothing has yet been reported on its protective effect against hyperammonemia, the main culprit behind the symptoms of HE. Here, we evaluated the effect of UMB against ammonium chloride (NH4Cl)-induced hyperammonemia, oxidative stress, inflammation and hematological alterations in rats. We demonstrated the modulatory role of UMB on the glutamate-nitric oxide (NO)-cGMP pathways in the cerebrum of rats. Rats received intraperitoneal injections of NH4Cl (3 times/week) for 8 weeks and concomitantly received 50 mg/kg UMB. NH4Cl-induced rats showed significantly elevated blood ammonia and liver function markers. Lipid peroxidation and NO were increased in the liver and cerebrum of rats while the antioxidant defenses were declined. UMB significantly reduced blood ammonia, liver function markers, lipid peroxidation and NO, and enhanced the antioxidant defenses in NH4Cl-induced rats. UMB significantly prevented anemia, leukocytosis, thrombocytopenia and prolongation of PT and aPTT. Hyperammonemic rats showed elevated levels of cerebral TNF-α, IL-1ß and glutamine as well as increased activity and expression of Na+/K+-ATPase, effects that were significantly reversed by UMB. In addition, UMB down-regulated nitric oxide synthase and soluble guanylate cyclase in the cerebrum of hyperammonemic rats. In conclusion, this study provides evidence that UMB protects against hyperammonemia via attenuation of oxidative stress and inflammation. UMB prevents hyperammonemia associated hematological alterations and therefore represents a promising protective agent against the deleterious effects of excess ammonia.

Abordagem metabolômica no estudo de exposição gestacional à fumaça de Cannabis sativa em cobaias / A metabolomics study of gestational exposure to smoke of Cannabis sativa in mice

Os estudos de metabolômica ganham importância a cada dia, por ajudarem a explicar processos biológicos em situações normais (fisiológicas) ou patológicas. Oferecem uma nova visão sobre o impacto funcional da expressão gênica, complementando os estudos de sequenciamento gênico, que negligenciam o impacto da exposição ao meio ambiente na etiologia de doenças. A metabolômica tem sido aplicada na toxicologia, mostrando que o perfil metabólico comparativo de duas situações, controle e teste, pode desempenhar um papel importante na descoberta e validação de biomarcadores, além de contribuir para o entendimento e consequente interpretação dos mecanismos de ação tóxica de xenobióticos. Este projeto de pesquisa tem por objetivo utilizar uma abordagem metabolômica para avaliar o impacto de alterações metabólicas no cérebro da prole de camundongos, ocorridas após exposição (via inalação) à fumaça decorrente da queima de maconha (Cannabis sativa). Fêmeas gestantes foram expostas a doses diárias de Cannabis sativa ou ar filtrado durante todo o período gestacional. Após o nascimento, os filhotes machos ao atingirem a idade para o desmame, considerado como fase adolescente, foram separados de suas respectivas mães e expostos à Cannabis sativa ou ar filtrado por mais 60 dias. As amostras de cérebro da prole foram submetidas a análises por cromatografia em fase gasosa acoplada a espectrometria de massas (CG-MS) numa abordagem metabolômica global (untargeted metabolomics). Os perfis metabólicos dos cérebros dos animais expostos (grupo teste) foram comparados com os obtidos na análise do grupo controle (não expostos), sendo identificados os metabólitos discriminadores candidatos. Estavam alterados os metabólitos: isoleucina, uréia, leucina, GABA, ácido succínico, ácido fumárico, serina, treonina, creatinina, ácido glutâmico, ácido acetilaspártico, glicerol -1 -fosfato, ácido ascórbico, tirosina, ácido cítrico, adenina, hipoxantina, inosina e uracila. A partir dos resultados apresentados, pode-se observar, que tanto a exposição gestacional à Cannabis sativa, quanto a exposição da prole na fase adolescente, provocam alterações metabólicas importantes. Os metabólitos significativamente alterados estão envolvidos no ciclo do ácido tricarboxílico, responsável pela respiração mitocondrial, na produção de energia, atuam na biossíntese de aminoácidos, glicólise, estresse oxidativo, podendo alterar o desenvolvimento e maturação do cérebro. Os resultados são preliminares, mas contribuem para o melhor entendimento dos mecanismos toxicológicos envolvidos na exposição crônica causada por essa droga, contribuindo para a prevenção e diagnóstico de danos no desenvolvimento fetal e adolescente

Metabolomics studies gain importance each day because they help explain biological processes in normal (physiological) or pathological situations. They provide a new insight into the functional impact of environmental gene expression, complementing gene sequencing studies that neglect the impact of environmental exposure on the etiology of diseases. Metabolomics has been applied in toxicology, showing that the comparative metabolic profile of two situations, control and test, can play an important role in the discovery and validation of biomarkers, in addition to contributing to the understanding and interpretation of the toxic action mechanisms of xenobiotics. This research project aims to use a metabolomic approach to evaluate the impact of metabolic changes in the brain of the offspring of mice, which occurred after exposure (via inhalation) to the smoke from the burning Cannabis sativa. Pregnant females were exposed to daily doses of Cannabis sativa or filtered air throughout the gestational period. After birth, male offspring were reached adolescents weaning age were separated from their respective mothers and exposed to Cannabis sativa or to the filtrate for another 60 days. Offspring brain samples were analyzed by gas chromatography coupled to mass spectrometry (GC-MS) in a global metabolomic approach (non-target metabolomics). Metabolic profiles of the exposed animals brains (test group) were compared with those obtained in the control group (non-exposed), and the candidate discriminant metabolites were identified. The metabolites were altered: isoleucine, urea, leucine, GABA, succinic acid, fumaric acid, serine, threonine, creatine, glutamic acid, acetyl aspartic acid, glycerol-1-phosphate, ascorbic acid, tyrosine, citric acid, adenine, hypoxanthine, inosine and uracil were altered. From the results presented, it can be observed that both the gestational exposure in Cannabis sativa and the exposure of the adolescent phase exposure, induced important metabolic alterations. Significantly altered metabolites are involved in the tricarboxylic acid, which are responsible for mitochondrial respiration, in energy production, act at the amino acid biosynthesis, glycolysis, oxidative stress, which may alter the development and maturation of the brain. The results are preliminary but contribute to a better understanding of the mechanisms of toxicity and of fetal and adolescent infection

Caffeic acid phenethyl ester protects the brain against hexavalent chromium toxicity by enhancing endogenous antioxidants and modulating the JAK/STAT signaling pathway.

Hexavalent chromium [Cr(VI)] is commonly used in industry, and is a proven toxin and carcinogen. However, the information regarding its neurotoxic mechanism is not completely understood. The present study was designed to scrutinize the possible protective effects of caffeic acid phenethyl ester (CAPE), a bioactive phenolic of propolis extract, on Cr(VI)-induced brain injury in rats, with an emphasis on the JAK/STAT signaling pathway. Rats received 2mg/kgK2CrO4 and concurrently treated with 20mg/kg CAPE for 30 days. Cr(VI)-induced rats showed a significant increase in cerebral lipid peroxidation, nitric oxide and pro-inflammatory cytokines, with concomitantly declined antioxidants and acetylcholinesterase. CAPE attenuated oxidative stress and inflammation and enhanced antioxidant defenses in the cerebrum of rats. Cr(VI) significantly up-regulated JAK2, STAT3 and SOCS3, an effect that was reversed by CAPE. In conclusion, CAPE protects the brain against Cr(VI) toxicity through abrogation of oxidative stress, inflammation and down-regulation of JAK2/STAT3 signaling in a SOCS3-independent mechanism.

Excess Manganese-Induced Apoptosis in Chicken Cerebrums and Embryonic Neurocytes.

There were many studies about the effect of excess manganese (Mn) on nervous system apoptosis; however, Mn-induced apoptosis in chicken cerebrums and embryonic neurocytes was unclear. The purpose of this study was to investigate the effect of excess Mn on chicken cerebrum and embryonic neurocyte apoptosis. Seven-day-old Hyline male chickens were fed either a commercial diet or three levels of manganese chloride (MnCl2)-added commercial diets containing 600-, 900-, and 1800-mg/kg-Mn diet, respectively. On the 30th, 60th, and 90th days, cerebrums were collected. Fertilized Hyline chicken eggs were hatched for 6-8 days and were selected. Embryonic neurocytes with 0, 0.5, 1, 1.5, 2, 2.5, and 3 mM Mn were collected and were cultured for 12, 24, 36, and 48 h, respectively. The following research contents were performed: superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) activities; tumor protein p53 (p53), B cell lymphoma-2 (Bcl-2), B cell lymphoma extra large (Bcl-x), Bcl-2-associated X protein (Bax), Bcl-2 homologous antagonist/killer (Bak), fas, and caspase-3 messenger RNA (mRNA) expression; and morphologic observation. The results indicated that excess Mn inhibited SOD and T-AOC activities; induced p53, Bax, Bak, fas, and caspase-3 mRNA expression; and inhibited Bcl-2 and Bcl-x mRNA expression in chicken cerebrums and embryonic neurocytes. There were dose-dependent manners on all the above factors at all the time points and time-dependent manners on SOD activity of 1800-mg/kg-Mn group, T-AOC activity, and apoptosis-related gene mRNA expression in all the treatment groups in chicken cerebrums. Excess Mn induced chicken cerebrum and embryonic neurocyte apoptosis.

Effects of Zinc and N-Acetylcysteine in Damage Caused by Lead Exposure in Young Rats.

This study investigated the toxicity of rats exposed to lead acetate (AcPb) during the second phase of brain development (8-12 days postnatal) in hematological and cerebral parameters. Moreover, the preventive effect of zinc chloride (ZnCl2) and N-acetylcysteine (NAC) was investigated. Pups were injected subcutaneously with saline (0.9% NaCl solution), ZnCl2 (27 mg/kg/day), NAC (5 mg/kg/day) or ZnCl2 plus NAC for 5 days (3rd-7th postnatal days), and with saline (0.9% NaCl solution) or AcPb (7 mg/kg/day) in the five subsequent days (8th-12th postnatal days). Animals were sacrificed 21 days after the last AcPb exposure. Pups exposed to AcPb presented inhibition of blood porphobilinogen-synthase (PBG-synthase) activity without changes in hemoglobin content. ZnCl2 pre-exposure partially prevented PBG-synthase inhibition. Regarding neurotoxicity biomarkers, animals exposed to AcPb presented a decrease in cerebrum acetylcholinesterase (AChE) activity and an increase in Pb accumulation in blood and cerebrum. These changes were prevented by pre-treatment with ZnCl2, NAC, and ZnCl2 plus NAC. AcPb exposure caused no alteration in behavioral tasks. In short, results show that AcPb inhibited the activity of two important enzymatic biomarkers up to 21 days after the end of the exposure. Moreover, ZnCl2 and NAC prevented the alterations induced by AcPb.

Effects of vanillin on potassium bromate-induced neurotoxicity in adult mice: impact on behavior, oxidative stress, genes expression, inflammation and fatty acid composition.

CONTEXT: Vanillin is known to possess important antioxidant activity. OBJECTIVE: The current study was conducted to establish the therapeutic efficiency of vanillin against potassium bromate (KBrO3)-induced depression-like behavior and oxidative stress in mice. MATERIAL AND METHODS: Mice were exposed during 15 days either to potassium bromate (KBrO3), KBrO3+ vanillin or to only vanillin. RESULTS: Our results revealed a significant modification in the fatty acid composition of the KBrO3-treated mice. In addition, KBrO3 induced a significant reduction in enzymatic activities and gene expressions, Na+ -K+ and Mg2+-ATPases, acetylcholinesterase and butylcholinesterase activities. The gene expression of tumor necrosis factor-α, interleukin-1ß, interleukin-6 and COX2, significantly increased in the cerebrum of KBrO3-treated group. Histopathological observations were consistent with these effects. Co-treatment with vanillin significantly attenuated KBrO3-induced oxidative stress and inflammation. CONCLUSION: This work suggests that vanillin mitigates KBrO3-induced depression, and that this neuroprotective effect proceeds through anti-oxidant and anti-inflammatory activities.

Particulate air pollutants, APOE alleles and their contributions to cognitive impairment in older women and to amyloidogenesis in experimental models.

Exposure to particulate matter (PM) in the ambient air and its interactions with APOE alleles may contribute to the acceleration of brain aging and the pathogenesis of Alzheimer's disease (AD). Neurodegenerative effects of particulate air pollutants were examined in a US-wide cohort of older women from the Women's Health Initiative Memory Study (WHIMS) and in experimental mouse models. Residing in places with fine PM exceeding EPA standards increased the risks for global cognitive decline and all-cause dementia respectively by 81 and 92%, with stronger adverse effects in APOE ɛ4/4 carriers. Female EFAD transgenic mice (5xFAD+/-/human APOE ɛ3 or ɛ4+/+) with 225 h exposure to urban nanosized PM (nPM) over 15 weeks showed increased cerebral ß-amyloid by thioflavin S for fibrillary amyloid and by immunocytochemistry for Aß deposits, both exacerbated by APOE ɛ4. Moreover, nPM exposure increased Aß oligomers, caused selective atrophy of hippocampal CA1 neurites, and decreased the glutamate GluR1 subunit. Wildtype C57BL/6 female mice also showed nPM-induced CA1 atrophy and GluR1 decrease. In vitro nPM exposure of neuroblastoma cells (N2a-APP/swe) increased the pro-amyloidogenic processing of the amyloid precursor protein (APP). We suggest that airborne PM exposure promotes pathological brain aging in older women, with potentially a greater impact in ɛ4 carriers. The underlying mechanisms may involve increased cerebral Aß production and selective changes in hippocampal CA1 neurons and glutamate receptor subunits.

Galactose alters markers of oxidative stress and acetylcholinesterase activity in the cerebrum of rats: protective role of antioxidants.

We evaluated the in vitro effects of galactose at 0.1, 3.0, 5.0 and 10.0 mM on thiobarbituric acid-reactive substances (TBA-RS), total sulfhydryl content, protein carbonyl content, on the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and on acetylcholinesterase (AChE) activity in the cerebral cortex, cerebellum and hippocampus of rats. We also investigated the influence of the antioxidants (each at 1 mM), α-tocopherol, ascorbic acid and glutathione, on the effects elicited by galactose on the parameters tested. Results showed that galactose, at a concentration of 3.0 mM, enhanced TBA-RS levels in the hippocampus, cerebral cortex and cerebellum of rats. In the cerebral cortex, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS and protein carbonyl content, and at 10.0 mM increased CAT activity and decreased AChE activity. In the cerebellum, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS, SOD and GSH-Px activities. In the hippocampus, galactose at concentrations of 5.0 and 10.0 mM increased TBA-RS and CAT activity and at 10.0 mM decreased GSH-Px. Data showed that at the pathologically high concentration (greater than 5.0 mM), galactose induces lipid peroxidation, protein carbonylation, alters antioxidant defenses in the cerebrum, and also alters cholinesterase activity. Trolox, ascorbic acid and glutathione addition prevented the majority of alterations in oxidative stress parameters and the decrease in AChE activity that were caused by galactose. Our findings lend support to a potential therapeutic strategy for this condition, which may include the use of appropriate antioxidants for ameliorating the damage caused by galactose.

Characterizing the mode of action of extracellular Connexin43 channel blocking mimetic peptides in an in vitro ischemia injury model.

BACKGROUND: Non-selective Connexin43 hemichannels contribute to secondary lesion spread. The hemichannel blocking peptidomimetic Peptide5, derived from the second extracellular loop of the human Connexin43 protein, prevents lesion spread and reduces vascular permeability in preclinical models of central nervous system injury. The molecular mode of action of Peptide5, however, was unknown and is described here. METHODS: Human cerebral microvascular endothelial cells and APRE-19 cells were used. Scrape loading was used to assess gap junction function and hypoxic, acidic ion-shifted Ringer solution induced ATP release used to assess hemichannel function. Peptide modifications, including amino acid substitutions and truncations, and competition assays were used to demonstrate Peptide5 functional specificity and site of action respectively. RESULTS: Peptide5 inhibits Connexin43 hemichannel-mediated ATP release by acting on extracellular loop two of Connexin43, adjacent to its matching sequence within the protein. Precise sequence specificity is important for hemichannel block, but less so for uncoupling of gap junction channels (seen only at high concentrations). The SRPTEKT motif is central to Peptide5 function but on its own is not sufficient to inhibit hemichannels. Both the SRPTEKT motif and Peptide5 reduce gap junction communication, but neither uncoupling below 50%. CONCLUSIONS: Reduced gap junction coupling at high peptide concentrations appears to be relatively non-specific. However, Peptide5 at low concentrations acts upon extracellular loop two of Connexin43 to block hemichannels in a precise, sequence specific manner. GENERAL SIGNIFICANCE: The concentration dependent and sequence specific action of Peptide5 supports its development for the treatment of retinal injury and chronic disease, as well as other central nervous system injury and disease conditions.

Neuroprotective Effect of Antioxidants and Moderate Hypoxia as Combined Preconditioning in Cerebral Ischemia.

We studied combined effect of moderate hypoxia and compounds pQ-4, pQ-915, pQ-1032, and pQ-1104 on neurological deficit and survival of rats after bilateral ligation of common carotid arteries. Preconditioning including moderate hypoxia and treatment with compound pQ-4 produced a neuroprotective effect and increased animal survival during the early (by 51%) and late (by 33.5%) periods of modeled ischemia and reduced neurological deficit (by 50% and 41%, respectively). Moreover, this combination of preconditioning factors prevented postischemic excessive activation of free radical oxidation in brain hemispheres and blood serum.

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.

Enhanced neural response to anticipation, effort and consummation of reward and aversion during bupropion treatment.

BACKGROUND: We have previously shown that the selective serotonergic reuptake inhibitor, citalopram, reduces the neural response to reward and aversion in healthy volunteers. We suggest that this inhibitory effect might underlie the emotional blunting reported by patients on these medications. Bupropion is a dopaminergic and noradrenergic reuptake inhibitor and has been suggested to have more therapeutic effects on reward-related deficits. However, how bupropion affects the neural responses to reward and aversion is unclear. METHOD: Seventeen healthy volunteers (9 female, 8 male) received 7 days bupropion (150 mg/day) and 7 days placebo treatment, in a double-blind crossover design. Our functional magnetic resonance imaging task consisted of three phases; an anticipatory phase (pleasant or unpleasant cue), an effort phase (button presses to achieve a pleasant taste or to avoid an unpleasant taste) and a consummatory phase (pleasant or unpleasant tastes). Volunteers also rated wanting, pleasantness and intensity of the tastes. RESULTS: Relative to placebo, bupropion increased activity during the anticipation phase in the ventral medial prefrontal cortex (vmPFC) and caudate. During the effort phase, bupropion increased activity in the vmPFC, striatum, dorsal anterior cingulate cortex and primary motor cortex. Bupropion also increased medial orbitofrontal cortex, amygdala and ventral striatum activity during the consummatory phase. CONCLUSIONS: Our results are the first to show that bupropion can increase neural responses during the anticipation, effort and consummation of rewarding and aversive stimuli. This supports the notion that bupropion might be beneficial for depressed patients with reward-related deficits and blunted affect.