Aluminum and copper in drinking water enhance inflammatory or oxidative events specifically in the brain

Responses of zebra and quagga mussels to copper and tribytiltin exposure: Bioconcentration, metabolic and cardiac biomarkers

One of the top ecological priorities is to find sensitive indicators for pollution monitoring. This study focuses on the bioconcentration and responses (condition index, survival, oxygen consumption, heart rates, and oxidative stress and neurotoxic effect biomarkers) of mussels from the Volga River basin, Dreissena polymorpha and Dreissena bugensis, to long-term exposure to toxic chemicals such as tributyltin (TBT, 25 and 100 ng/L) and copper (Cu, 100 and 1000 μg/L). We found that TBT was present in the tissues of zebra and quagga mussels in comparable amounts, whereas the bioconcentration factor of Cu varied depending on its concentration in water. Differences in responses between the two species were revealed. When exposed to high Cu concentrations or a Cu-TBT mixture, quagga mussels had a lower survival rate and a longer heart rate recovery time than zebra mussels. TBT treatment caused neurotoxicity (decreased acetylcholinesterase activity) and oxidative stress (increased levels of thiobarbituric acid reactive substances) in both species. TBT and Cu levels in mussel tissues correlated positively with the condition index, but correlated with the level of acetylcholinesterase in the mussel gills. The principal component analysis revealed three main components: the first consists of linear combinations of 14 variables reflecting TBT water pollution, TBT and Cu levels in mussel tissues, and biochemical indicators; the second includes Cu water concentration, cardiac tolerance, and mussel size; and the third combines weight, metabolic rate, and heart rates. Quagga mussels are less tolerable to contaminants than zebra mussels, so they may be used as a sensitive indicator.

Copper and cuproptosis: new therapeutic approaches for Alzheimer's disease

Copper (Cu) plays a crucial role as a trace element in various physiological processes in humans. Nonetheless, free copper ions accumulate in the brain over time, resulting in a range of pathological changes. Compelling evidence indicates that excessive free copper deposition contributes to cognitive decline in individuals with Alzheimer's disease (AD). Free copper levels in the serum and brain of AD patients are notably elevated, leading to reduced antioxidant defenses and mitochondrial dysfunction. Moreover, free copper accumulation triggers a specific form of cell death, namely copper-dependent cell death (cuproptosis). This article aimed to review the correlation between copper dysregulation and the pathogenesis of AD, along with the primary pathways regulating copper homoeostasis and copper-induced death in AD. Additionally, the efficacy and safety of natural and synthetic agents, including copper chelators, lipid peroxidation inhibitors, and antioxidants, were examined. These treatments can restore copper equilibrium and prevent copper-induced cell death in AD cases. Another aim of this review was to highlight the significance of copper dysregulation and promote the development of pharmaceutical interventions to address it.

A correlation of the adsorption capacity of perovskite/biochar composite with the metal ion characteristics

LaFeO₃/biochar composite is prepared by cellulose-modified microwave-assisted method at 450 °C. The structure is identified by Raman spectrum which, consists of characteristics biochar bands and octahedral perovskite chemical shifts. The morphology is examined by scanning electron microscope (SEM); two phases are observed, rough microporous biochar and orthorhombic perovskite particles. The BET surface area of the composite is 57.63 m²/g. The prepared composite is applied as a sorbent for the removal of Pb²⁺, Cd²⁺, and Cu²⁺ ions from aqueous solutions and wastewater. The adsorption ability reaches a maximum at pH > 6 for Cd²⁺, and Cu²⁺ ions, and is pH-independent for Pb²⁺ ions adsorption. The adsorption follows pseudo 2nd order kinetic model, Langmuir isotherm for Pb²⁺ ions, and Temkin isotherms for Cd²⁺, and Cu²⁺ ions. The maximum adsorption capacities, q_m, are 606, 391, and 112 mg/g for Pb²⁺, Cd²⁺, and Cu²⁺ ions, respectively. The electrostatic interaction is responsible for the adsorption of Cd²⁺, and Cu²⁺ ions on LaFeO₃/biochar composite. In case of Pb²⁺ ions form a complex with the surface functional groups of the adsorbate. LaFeO₃/biochar composite shows high selectivity for the studied metal ions and excellent performance in real samples. The proposed sorbent can be easily regenerated and effectively reused.

Healthy lifestyles and wellbeing reduce neuroinflammation and prevent neurodegenerative and psychiatric disorders

Since the mid-20th century, Western societies have considered productivity and economic outcomes are more important than focusing on people's health and wellbeing. This focus has created lifestyles with high stress levels, associated with overconsumption of unhealthy foods and little exercise, which negatively affect people's lives, and subsequently lead to the development of pathologies, including neurodegenerative and psychiatric disorders. Prioritizing a healthy lifestyle to maintain wellbeing may slow the onset or reduce the severity of pathologies. It is a win-win for everyone; for societies and for individuals. A balanced lifestyle is increasingly being adopted globally, with many doctors encouraging meditation and prescribing non-pharmaceutical interventions to treat depression. In psychiatric and neurodegenerative disorders, the inflammatory response system of the brain (neuroinflammation) is activated. Many risks factors are now known to be linked to neuroinflammation such as stress, pollution, and a high saturated and trans fat diet. On the other hand, many studies have linked healthy habits and anti-inflammatory products with lower levels of neuroinflammation and a reduced risk of neurodegenerative and psychiatric disorders. Sharing risk and protective factors is critical so that individuals can make informed choices that promote positive aging throughout their lifespan. Most strategies to manage neurodegenerative diseases are palliative because neurodegeneration has been progressing silently for decades before symptoms appear. Here, we focus on preventing neurodegenerative diseases by adopting an integrated "healthy" lifestyle approach. This review summarizes the role of neuroinflammation on risk and protective factors of neurodegenerative and psychiatric disorders.

Alterations in metal homeostasis occur prior to canonical markers in Huntington disease

The importance of metal biology in neurodegenerative diseases such as Huntingtin Disease is well documented with evidence of direct interactions between metals such as copper, zinc, iron and manganese and mutant Huntingtin pathobiology. To date, it is unclear whether these interactions are observed in humans, how this impacts other metals, and how mutant Huntington alters homeostatic mechanisms governing levels of copper, zinc, iron and manganese in cerebrospinal fluid and blood in HD patients. Plasma and cerebrospinal fluid from control, pre-manifest, manifest and late manifest HD participants were collected as part of HD-Clarity. Levels of cerebrospinal fluid and plasma copper, zinc, iron and manganese were measured as well as levels of mutant Huntingtin and neurofilament in a sub-set of cerebrospinal fluid samples. We find that elevations in cerebrospinal fluid copper, manganese and zinc levels are altered early in disease prior to alterations in canonical biomarkers of HD although these changes are not present in plasma. We also evidence that CSF iron is elevated in manifest patients. The relationships between plasma and cerebrospinal fluid metal are altered based on disease stage. These findings demonstrate that there are alterations in metal biology selectively in the CSF which occur prior to changes in known canonical biomarkers of disease. Our work indicates that there are pathological changes related to alterations in metal biology in individuals without elevations in neurofilament and mutant Huntingtin.

Non-Ceruloplasmin Copper as a Stratification Biomarker of Alzheimer's Disease Patients: How to Measure and Use It

Alzheimer's disease (AD) is a type of dementia very common in the elderly. A growing body of recent evidence has linked AD pathogenesis to copper (Cu) dysmetabolism in the body. In fact, a subset of patients affected either by AD or by its prodromal form known as Mild Cognitive Impairment (MCI) have been observed to be unable to maintain a proper balance of Cu metabolism and distribution and are characterized by the presence in their serum of increased levels of Cu not bound to ceruloplasmin (non-ceruloplasmin Cu). Since serum non-ceruloplasmin Cu is a biomark- er of Wilson's disease (WD), a well-known condition of Cu-driven toxicosis, in this review, we pro- pose that in close analogy with WD, the assessment of non-ceruloplasmin Cu levels can be exploit- ed as a cost-effective stratification and susceptibility/risk biomarker for the identification of some AD/MCI individuals. The approach can also be used as an eligibility criterion for clinical trials aim- ing at investigating Cu-related interventions against AD/MCI.

Long-term exposure to low doses of aluminum affects mineral content and microarchitecture of rats alveolar bone

Aluminum (Al) is one of the most found elements in nature in many forms, and human exposure can be quite common. Therefore, it is important to investigate the effects of exposure to Al mainly at low doses and for a prolonged period, in order to simulate human exposure in the periodontium, an important structure for support and protection of the teeth. This investigation aimed to study the aluminum chloride (AlCl₃) toxicological effects in the mineral composition and micromorphology of the alveolar bone of rats. Two groups of eight male Wistar rats were used for the experiment. AlCl₃ group was exposed to AlCl₃ orally at a dose of 8.3 mg/kg/day for 60 days, while the control group received only distilled water. After that, the mandibles were collected and submitted to the following analyses: Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray microtomography analysis; blood was also collected for determination of Al circulating levels. Our data showed that AlCl₃ was capable of increasing Al circulating levels in blood. It was able to promote changes in the mineral content and triggers significant changes in the mineralized bone microstructure, such as number and thickness of trabeculae, being associated with alveolar bone-loss.

Atrazine Inhalation Causes Neuroinflammation, Apoptosis and Accelerating Brain Aging

BACKGROUND

exposure to environmental contaminants has been linked to an increased risk of neurological diseases and poor outcomes. Chemical name of Atrazine (ATR) is 6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine, and it is the most commonly used broad-spectrum herbicide in agricultural crops. Several studies have demonstrated that ATR has the potential to be harmful to the brain's neuronal circuits. Until today nobody has explored the effect of ATR inhalation on young and aged mice.

METHODS

young and aged mice were subject to 25 mg of ATR in a vehicle made with saline and 10% of Dimethyl sulfoxide (DMSO) every day for 28 days. At the end of experiment different behavioral test were made and brain was collected.

RESULTS

exposure to ATR induced the same response in terms of behavioral alterations and motor and memory impairment in mice but in aged group was more marked. Additionally, in both young and aged mice ATR inhalations induced oxidative stress with impairment in physiological antioxidant response, lipid peroxidation, nuclear factor kappa-light-chain-enhancer of activated B cells (nf-κb) pathways activation with consequences of pro-inflammatory cytokines release and apoptosis. However, the older group was shown to be more sensitive to ATR inhalation.

CONCLUSIONS

our results showed that aged mice were more susceptible compared to young mice to air pollutants exposure, put in place a minor physiologically response was seen when exposed to it.

Allicin ameliorates aluminium- and copper-induced cognitive dysfunction in Wistar rats: relevance to neuro-inflammation, neurotransmitters and Aβ(1-42) analysis

Alzheimer's disease (AD) is a multifactorial neurological disorder associated with neuropathological and neurobehavioral changes, like cognition and memory loss. Pathological hallmarks of AD comprise oxidative stress, formation of insoluble β-amyloid (Aβ) plaques, intracellular neurofibrillary tangles constituted by hyperphosphorylated tau protein (P-tau), neurotransmitters dysbalanced (DA, NE, 5-HT, GABA and Glutamate) and metal deposition. Chronic exposure to metals like aluminium and copper causes accumulation of Aβ plaques, promotes oxidative stress, neuro-inflammation, and degeneration of cholinergic neurons results in AD-like symptoms. In the present study, rats were administered with aluminium chloride (200 mg/kg p.o) and copper sulfate (0.5 mg/kg p.o) alone and in combination for 28 days. Allicin (10 and 20 mg/kg i.p) was administered from day 7 to day 28. Spatial and recognition memory impairment analysis was performed using Morris water maze, Probe trial, and Novel Object Recognition test. Animals were sacrificed on day 29, brain tissue was isolated, and its homogenate was used for biochemical (lipid peroxidation, nitrite, and glutathione), neuro-inflammatory (IL-1β, IL-6 and TNF- α), neurotransmitters (DA, NE, 5-HT, GABA and Glutamate), Aβ_(1-42) level, Al concentration estimation, and Na⁺/K⁺-ATPase activity. In the present study, aluminium chloride and copper sulfate administration increased oxidative stress, inflammatory cytokines release, imbalanced neurotransmitters' concentration, and promoted β-amyloid accumulation and Na⁺/K⁺-ATPase activity. Treatment with allicin dose-dependently attenuated these pathological events via restoration of antioxidants, neurotransmitters concentration, and inhibiting cytokine release and β-amyloid accumulation. Moreover, allicin exhibited the neuroprotective effect through antioxidant, anti-inflammatory, neurotransmitters restoration, attenuation of neuro-inflammation and β-amyloid-induced neurotoxicity.

As3+ or/and Cu2+ exposure triggers oxidative stress imbalance, induces inflammatory response and apoptosis in chicken brain

Arsenic (As) and copper (Cu) are common environmental pollutants in nature. When they are excessively present in living organisms, they can cause heavy metal poisoning. There were relatively few studies of the toxicological concentrations of As and Cu in the brain using chicken as a model. Therefore, in this study, arsenic trioxide or/and copper sulfate were added to chicken diets for a 12-week toxicity test. The test results showed that excessive intake of As or/and Cu led to a significant reduction in the total antioxidant capacity (T-AOC), catalase (CAT) and hydroxyl radicals. And significant increase in nitric oxide synthase (NOS) indicates an imbalanced oxidation reaction. In addition, the increase in heat shock protein (HSPs), the increase of NF-κB pathway-related pro-inflammatory mediators, the change of apoptosis factors on the death receptor and mitochondrial apoptosis pathway show that, As or/and Cu exposure induced chicken brain has heat shock response (HSP), tissue inflammation and apoptosis. This damage is inseparable from the oxidative imbalance. It is worth noting that these injury changes are time-dependent, and the combined effect of these two metals is more severe than that of a single group of injuries. Our findings can inform the regulation of animal feed additives and avoid agricultural economic losses or biological health damage.

The Possible Neuroprotective Effect of Silymarin against Aluminum Chloride-Prompted Alzheimer's-Like Disease in Rats

Alzheimer's disease (AD) is a worldwide rapidly growing neurodegenerative disease. Here, we elucidated the neuroprotective effects of silymarin (SM) on the hippocampal tissues of aluminum chloride (AlCl3)-induced Alzheimer-like disease in rats using biochemical, histological, and ultrastructural approaches. Forty rats were divided into control, SM, AlCl3, and AlCl3 + SM groups. Biochemically, AlCl3 administration resulted in marked elevation in levels of lipid peroxidation (LPO) and nitric oxide (NO) and decrease in levels of reduced glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD). Moreover, AlCl3 significantly increased tumor necrosis factor-α (TNF-α), interleukin-1beta (IL-1β), and acetylcholinesterase (AChE) activities. Furthermore, myriad histological and ultrastructural alterations were recorded in the hippocampal tissues of AlCl3-treated rats represented as marked degenerative changes of pyramidal neurons, astrocytes, and oligodendrocytes. Additionally, some myelinated nerve fibers exhibited irregular arrangement of their myelin coats, while the others revealed focal degranulation of their myelin sheaths. Severe defects in the blood-brain barrier (BBB) were also recorded. However, co-administration of SM with AlCl3 reversed most of the biochemical, histological, and ultrastructural changes triggered by AlCl3 in rats. The results of the current study indicate that SM can potentially mend most of the previously evoked neuronal damage in the hippocampal tissues of AlCl3-kindled rats.

Distinctive cellular response to aluminum based adjuvants

Aluminum-based adjuvants (ABAs) are used in human vaccines to enhance the magnitude of protective immune responses elicited against specific pathogens. One hypothesis is that stress signals released by aluminum-exposed necrotic cells play a role in modulating an immune response that contributes to the adjuvant's effectiveness. We hypothesized that aluminum adjuvant-induced necrosis would be similar irrespective of cellular origin or composition of the adjuvant. To test this hypothesis, human macrophages derived from peripheral monocytic cell line (THP-1) and cells derived from the human brain (primary astrocytes) were evaluated. Three commercially available formulations of ABAs (Alhydrogel, Imject alum, and Adju-Phos) were examined. Alum was also used as a reference. Cell viability, reactive oxygen species formation, and production of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) were quantified. Cells were exposed to different concentrations (10-100 μg/mL) of the adjuvants for 24 h or 72 h. The two FDA approved adjuvants (Alhydrogel and Adju-Phos) decreased cell viability in both cell types. At the 72 h time point, the decrease in viability was accompanied with increased ROS formation. The size of the aluminum agglomerates was not relatable to the changes observed. After exposure to ABAs, astrocytes and macrophages presented a distinct profile of cytokine secretion which may relate to the function and unique characteristics of each cell type. These variations indicate that aluminum adjuvants may have differing capability of activating cells of different origin and thus their utility in specific vaccine design should be carefully assessed for optimum efficacy.

Oxidative stress, apoptosis and inflammatory responses involved in copper-induced pulmonary toxicity in mice

At present, there are few studies focused on the relationship between copper (Cu) and oxidative stress, apoptosis, or inflammatory responses in animal and human lungs. This study was conducted to explore the effects of Cu on pulmonary oxidative stress, apoptosis and inflammatory responses in mice orally administered with 0 mg/kg (control), 10 mg/kg, 20 mg/kg, and 40 mg/kg of CuSO₄ for 42 days. The results showed that CuSO₄ increased ROS production, and MDA, 8-OHdG and NO contents as well as iNOS activities and mRNA expression levels. Meanwhile, CuSO₄ reduced the activities and mRNA expression levels of antioxidant enzymes (GSH-Px, CAT, and SOD) and GSH contents, and ASA and AHR abilities. Also, CuSO₄ induced apoptosis, which was accompanied by decreasing Bcl-2, Bcl-xL mRNA expression levels and protein expression levels, and increasing Bax, Bak, cleaved-caspase-3, cleaved-caspase-9 mRNA, and protein expression levels, and Bax/Bcl-2 ratio. Concurrently, CuSO₄ caused inflammation by increasing MPO activities and activating the NF-κB signalling pathway, and down-regulating the mRNA and protein expression levels of anti-inflammatory cytokines (IL-2, IL-4, IL-10). In conclusion, the abovementioned findings demonstrated that over 10 mg/kg CuSO₄ can cause oxidative stress, apoptosis, and inflammatory responses, which contribute to pulmonary lesions and dysfunction in mice.

Systemic Exposure to Air Pollution Induces Oxidative Stress and Inflammation in Mouse Brain, Contributing to Neurodegeneration Onset

In northern Italy, biomass burning-derived (BB) particles and diesel exhaust particles (DEP) are considered the most significant contributors to ultrafine particle (UFP) emission. However, a comparison between their impact on different brain regions was not investigated until now. Therefore, male BALB/c mice were treated with a single or three consecutive intratracheal instillations using 50 µg of UFPs in 100 µL of isotonic saline solution or 100 µL of isotonic saline solution alone, and brains were collected and analyzed. Proteins related to oxidative stress and inflammation, as well as Alzheimer's disease markers, were examined in the hippocampus, cerebellum, and the rest of the brain (RoB). Histopathological examination of the brain was also performed. Moreover, correlations among different brain, pulmonary, and cardiovascular markers were performed, allowing us to identify the potentially most stressful UFP source. Although both acute exposures induced inflammatory pathways in mouse brain, only DEP showed strong oxidative stress. The sub-acute exposure also induced the modulation of APP and BACE1 protein levels for both UFPs. We observed that DEP exposure is more harmful than BB, and this different response could be explained by this UFP's different chemical composition and reactivity.

Abdullah A, Ozoemena KI, Elzatahry A. Unveiling Fabrication and Environmental Remediation of MXene-Based Nanoarchitectures in Toxic Metals Removal from Wastewater: Strategy and Mechanism

Efficient approaches for toxic metal removal from wastewater have had transformative impacts to mitigating freshwater scarcity. Adsorption is among the most promising purification techniques due to its simplicity, low cost, and high removal efficiency at ambient conditions. MXene-based nanoarchitectures emerged as promising adsorbents in a plethora of toxic metal removal applications. This was due to the unique hydrophilicity, high surface area, activated metallic hydroxide sites, electron-richness, and massive adsorption capacity of MXene. Given the continual progress in the rational design of MXene nanostructures for water treatment, timely updates on this field are required that deeply emphasize toxic metal removal, including fabrication routes and characterization strategies of the merits, advantages, and limitations of MXenes for the adsorption of toxic metals (i.e., Pb, Cu, Zn, and Cr). This is in addition to the fundamentals and the adsorption mechanism tailored by the shape and composition of MXene based on some representative paradigms. Finally, the limitations of MXenes and their potential future research perspectives for wastewater treatment are also discussed. This review may trigger scientists to develop novel MXene-based nanoarchitectures with well-defined shapes, compositions, and physiochemical merits for efficient, practical removal of toxic metals from wastewater.

Potential Role of Trace Elements (Al, Cu, Zn, and Se) in Multiple Sclerosis Physiopathology

Multiple sclerosis (MS) is an unpredictable disease of the central nervous system. The cause of MS is not known completely, and pathology is specified by involved demyelinated areas in the white and gray matter of the brain and spinal cord. Inflammation and peripheral tolerance breakdown due to Treg cell defects and/or effector cell resistance are present at all stages of the disease. Several invading peripheral immune cells are included in the process of the disease such as macrophages, CD8+ T cells, CD4+ T cells, B cells, and plasma cells. Trace elements are known as elements found in soil, plants, and living organisms in small quantities. Some of them (e.g., Al, Cu, Zn, Mn, and Se) are essential for the body's functions like catalysts in enzyme systems, energy metabolism, etc. Al toxicity and Cu, Zn, and Se toxicity and deficiency can affect the immune system and following neuron inflammation and degeneration. These processes may result in MS pathology. Of course, factors such as lifestyle, environment, and industrialization can affect levels of trace elements in the human body.

The Nutritional Components of Beer and Its Relationship with Neurodegeneration and Alzheimer's Disease

The prevalence of degenerative diseases has risen in western countries. Growing evidence suggests that demenia and other cognition affectations are associated with ambient factors including specific nutrients, food ingredients or specific dietary patterns. Mediterranean diet adherence has been associated with various health benefits and decreased risk of many diseases, including neurodegenerative disorders. Beer, as part of this protective diet, contains compounds such as silicon and hops that could play a major role in preventing brain disorders. In this review, different topics regarding Mediterranean diet, beer and the consumption of their main compounds and their relation to neurological health have been addressed. Taking into account published results from our group and other studies, the hypothesis linking aluminum intoxication with dementia and/or Alzheimer’s disease and the potential role of regular beer has also been considered. Beer, in spite of its alcohol content, may have some health benefits; nonetheless, its consumption is not adequate for all subjects. Thus, this review analyzed some promising results of non-alcoholic beer on several mechanisms engaged in neurodegeneration such as inflammation, oxidation, and cholinesterase activity, and their contribution to the behavioral modifications induced by aluminum intoxication. The review ends by giving conclusions and suggesting future topics of research related to moderate beer consumption and/or the consumption of its major compounds as a potential instrument for protecting against neurodegenerative disease progression and the need to develop nutrigenetic and nutrigenomic studies in aged people and animal models.

Glycyrrhizic acid and silymarin alleviate the neurotoxic effects of aluminum in rats challenged with fructose-induced insulin resistance: possible role of toll-like receptor 4 pathway

Aluminum is implicated in the etiology of different neurodegenerative diseases, diabetes and cancer. The current study was conducted to evaluate the protective effects of glycyrrhizic acid (GAM) and silymarin (SLY) on AlCl₃-induced neurotoxicity in insulin resistant rats. Insulin resistance (IR) was induced by fructose (10%) in drinking water for 18 weeks. Rats received AlCl₃ (34 mg/kg/day) with or without fructose, GAM (40 mg/kg/day), or SLY (100 mg/kg/day). The administration of GAM or SLY suppressed AlCl₃-induced memory deficit, oxidative stress, and neuroinflammation in brain tissue of IR rats. Both agents inhibited AlCl₃-induced activation of TLR4 signaling pathway including the downstream activation of NF-κB. The results show that IR can partly exacerbate AlCl₃-induced neurotoxicity, particularly memory deficit and neuroinflammation. In addition, GAM and SLY showed promising neuroprotective effect against AlCl₃-induced brain damage in IR rats. The neuroprotection induced by these natural products might be mediated through their antioxidant and anti-inflammatory effects. The latter effect seems to be mediated via inhibition of TLR4 signaling pathway providing new insights on the mechanisms implicated in AlCl₃-induced neurotoxicity and the neuroprotection afforded by GAM and SLY.

Agricultural solid waste for sorption of metal ions, part II: competitive assessment in multielemental solution and lake water

Sugarcane bagasse and hydroponic lettuce roots were used as biosorbents for the removal of Cu(II), Fe(II), Mn(II), and Zn(II) from multielemental solutions and lake water, in batch processes. These biomasses were studied in natura (lettuce roots, NLR, and sugarcane bagasse, NSB) and chemically modified with HNO3 (lettuce roots, MLR, and sugarcane bagasse, MSB). The results showed higher adsorption efficiency for MSB and either NLR or MLR. The maximum adsorption capacities (qmax) in multielemental solution for Cu(II), Fe(II), Mn(II), and Zn(II) were 35.86, 31.42, 3.33, and 24.07 mg/g for NLR; 25.36, 27.95, 14.06, and 6.43 mg/g for MLR; 0.92, 3.94, 0.03, and 0.18 mg/g for NSB; and 54.11, 6.52, 16.7, and 1.26 mg/g for MSB, respectively. The kinetic studies with chemically modified biomasses indicated that sorption was achieved in the first 5 min and reached equilibrium around 30 min. Sorption of Cu(II), Fe(II), Mn(II), and Zn(II) in lake water by chemically modified biomasses was 24.31, 14.50, 8.03, and 8.21 mg/g by MLR, and 13.15, 10.50, 6.10, and 5.14 mg/g by MSB, respectively. These biosorbents are promising and low costs agricultural residues, and as for lettuce roots, these showed great potential even with no chemical modification.

Protective role of jaboticaba Plinia peruviana peel extract in copper-induced cytotoxicity in Allium cepa

Jaboticaba Plinia peruviana (Poir.) Govaerts is a Brazilian berry that presents high levels of polyphenols, which may play a key role in preventing cytotoxic and genotoxic effects of harmful agents. Although copper is an essential micronutrient that plays an important role in organisms, high copper concentrations may trigger toxicity to animals and plants. Here, we investigated whether Plinia peruviana hydroalcoholic extract prevents copper-induced cytotoxicity in Allium cepa root cells. Five different anthocyanins and phenolic compounds were identified in Plinia peruviana extract. Importantly, the exposure to 1.53 mg/L copper for 24 h impaired mitotic index, as well as increased mitosis disturbances and triggered DNA damage. Pre-incubation with Plinia peruviana extract (0.25 g/L and 0.75 g/L) for 3 h prevented copper-induced changes in the mitotic index and reduced the number of abnormal cells. In conclusion, we suggest that Plinia peruviana peel extract has protective effects against cellular and genetic disturbances induced by copper.

Oxidative stress-induced skeletal muscle injury involves in NF-κB/p53-activated immunosuppression and apoptosis response in copper (II) or/and arsenite-exposed chicken

The adverse effects of environmental toxicants such as copper and arsenic occur due to the generation of reactive oxygen species. Recent study also reported that both copper (Cu) and arsenic (As) may alter muscle regeneration. In order to assess the toxic effects of copper and arsenic on chicken skeletal muscle, chickens were subjected by different toxicologically relevant concentrations of copper or arsenic and their combination in diets for 12 weeks. Upon comparative analysis, a significantly higher malondialdehyde (MDA) and hydroxy radical content were observed in Cu or/and As exposed chicken skeletal muscle, which confirmed the strong lipid peroxidation nature of these two heavy metals. In addition, the depleted activity of catalase and glutathione peroxidase suggested the strong association of copper and arsenic with oxidative stress. Moreover, the higher elevation of pro-inflammatory mediators (NF-κB et al.) and Th1 bias immune system, suggested that exposure to Cu or/and As induces inflammation via NF-κB mediated response pathway. These results further coincided with inflammatory infiltration and nuclear condensation. Further, the execution of apoptosis machinery were characterized by a considerably elevated pro-apoptotic response and apoptotic index. In conclusion, the increased p53 levels detected in Cu or/and As treated chickens suggest the possibility that the NF-kB/p53 axis might lead to the impairment of immune-apoptosis cross talk in the present model.

Toxic metal(loid)-based pollutants and their possible role in autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social interaction, verbal and non-verbal communication, and stereotypic behaviors. Many studies support a significant relationship between many different environmental factors in ASD etiology. These factors include increased daily exposure to various toxic metal-based environmental pollutants, which represent a cause for concern in public health. This article reviews the most relevant toxic metals, commonly found, environmental pollutants, i.e., lead (Pb), mercury (Hg), aluminum (Al), and the metalloid arsenic (As). Additionally, it discusses how pollutants can be a possible pathogenetic cause of ASD through various mechanisms including neuroinflammation in different regions of the brain, fundamentally occurring through elevation of the proinflammatory profile of cytokines and aberrant expression of nuclear factor kappa B (NF-κB). Due to the worldwide increase in toxic environmental pollution, studies on the role of pollutants in neurodevelopmental disorders, including direct effects on the developing brain and the subjects' genetic susceptibility and polymorphism, are of utmost importance to achieve the best therapeutic approach and preventive strategies.

Early evidence of stress in immortalized neurons exposed to diesel particles: the role of lipid reshaping behind oxidative stress and inflammation

Diesel combustion is the major source of fine particle road emission, whose solid fraction is represented by diesel exhaust particles (DEP). Many studies indicate the contribution of DEP to the onset of different neurological diseases, such as Alzheimer's disease (AD), identifying oxidative stress and neuroinflammation as two cardinal processes of brain damage. This study aimed to investigate the effects of different concentrations of DEP (10 μg/ml and 50 μg/ml) on the mouse HT22 cells treated for 3 h or 24 h. Our results demonstrated that DEP contributed to an increased oxidative stress, defined by overexpression of HO-1, Hsp70 and Cyp1b1 protein levels. Moreover, an inflammatory-related processes were also observed, as COX-2 and iNOS levels were higher in treated cells when compared to the control. Furthermore, our investigations highlighted the alteration of fatty acid composition, total cholesterol content in cells and media, and of membrane fluidity, suggesting a lipid reshaping after DEP treatment. Finally, we detected APP and BACE1 increase after 24 h of treatment with 50 μg/ml of DEP. Indeed, our results propose a role of acute exposure in the onset of a deleterious mechanism for AD neurodegeneration, even though no differences were observed in p-APP ^Thr668 levels, BACE1 activity and APP C-terminal fragment beta amount.

Neurotoxicity Linked to Dysfunctional Metal Ion Homeostasis and Xenobiotic Metal Exposure: Redox Signaling and Oxidative Stress

SIGNIFICANCE

Essential metals such as copper, iron, manganese, and zinc play a role as cofactors in the activity of a wide range of processes involved in cellular homeostasis and survival, as well as during organ and tissue development. Throughout our life span, humans are also exposed to xenobiotic metals from natural and anthropogenic sources, including aluminum, arsenic, cadmium, lead, and mercury. It is well recognized that alterations in the homeostasis of essential metals and an increased environmental/occupational exposure to xenobiotic metals are linked to several neurological disorders, including neurodegeneration and neurodevelopmental alterations. Recent Advances: The redox activity of essential metals is key for neuronal homeostasis and brain function. Alterations in redox homeostasis and signaling are central to the pathological consequences of dysfunctional metal ion homeostasis and increased exposure to xenobiotic metals. Both redox-active and redox-inactive metals trigger oxidative stress and damage in the central nervous system, and the exact mechanisms involved are starting to become delineated.

CRITICAL ISSUES

In this review, we aim to appraise the role of essential metals in determining the redox balance in the brain and the mechanisms by which alterations in the homeostasis of essential metals and exposure to xenobiotic metals disturb the cellular redox balance and signaling. We focus on recent literature regarding their transport, metabolism, and mechanisms of toxicity in neural systems.

FUTURE DIRECTIONS

Delineating the specific mechanisms by which metals alter redox homeostasis is key to understand the pathological processes that convey chronic neuronal dysfunction in neurodegenerative and neurodevelopmental disorders. Antioxid. Redox Signal. 28, 1669-1703.

Potentiating role of copper on spatial memory deficit induced by beta amyloid and evaluation of mitochondrial function markers in the hippocampus of rats

Mounting evidence suggests that copper, a crucial element in normal brain function, plays an important role in the etiology of Alzheimer's disease, which is known as a neurodegenerative mitochondrial disorder. However, the precise mechanisms of its effects on cognitive and mitochondrial functions through the CNS have not been thoroughly recognized yet. In this study, we aimed to investigate the long-term (3-week) effects of copper sulfate (50, 100 and 200 mg kg^-1 day^-1) exposure on learning and memory as well as on mitochondrial function in the hippocampus of rats in the presence and absence of beta amyloid (1 μg μl^-1 per side) intrahippocampally (IH). After three weeks of copper exposure through drinking water, acquisition and retention of spatial memory were measured by the Morris water maze (MWM) test. Various parameters of mitochondrial function were also evaluated. Our data show that copper damaged the spatial learning and memory and also exacerbated the memory deficit induced by Aβ injection in rats in a dose-dependent manner. Mitochondria isolated from the hippocampus of rats treated with copper showed significant increases in ROS formation, mitochondrial swelling, lipid peroxidation, glutathione oxidation, outer membrane damage, and collapse of MMP, decreased cytochrome c oxidase activity, and finally increased ADP/ATP ratios. Our results indicate that copper overloading in the hippocampus of rats causes mitochondrial dysfunction and subsequent oxidative stress leading to cognitive impairment. This study also reveals that copper can potentiate Aβ deleterious effects on spatial memory and brain mitochondrial function.

Water Quality and Brain Function

In the United States, regulations are in place to ensure the quality of drinking water. Such precautions are intended to safeguard the health of the population. However, regulatory guidelines may at times fail to achieve their purpose. This may be due to lack of sufficient data regarding the health hazards of chronic low dose exposure to contaminants or the introduction of new substances that pose a health hazard risk that has yet to be identified. In this review, examples of different sources of contaminants in drinking water will be discussed, followed by an evaluation of some select individual toxicants with known adverse neurological impact. The ability of mixtures to potentially cause additive, synergistic, or antagonistic neurotoxic responses will be briefly addressed. The last section of the review will provide examples of select mechanisms by which different classes of contaminants may lead to neurological impairments. The main objective of this review is to bring to light the importance of considering trace amounts of chemicals in the drinking water and potential brain abnormalities. There is continued need for toxicology studies to better understand negative consequences of trace amounts of toxins and although it is beyond the scope of this brief overview it is hoped that the review will underscore the paucity of studies focused on determining how long-term exposure to minute levels of contaminants in drinking water may pose a significant health hazard.

Trace metal imaging in diagnostic of hepatic metal disease

The liver is the most central organ and the largest gland of the body that influences and controls a variety of metabolic and catabolic processes. It produces inconceivable many essential proteins, is responsible for the recovery of various food components, degrades toxins, mediates the bile production, and is involved in the excretion of unwanted metabolites. Several of these anabolic or catabolic functions of the liver depend on trace elements. These are either integral part of enzymes, cofactors, or act as chemical catalysts. Therefore, a lack of trace elements can lead to organ failure or systemic illness. Conversely, excessive hepatic trace element deposition resulting from genetic disorders, intoxication, extensive dietary supply, or long-term parenteral nutrition may cause hepatic inflammation, fibrosis, cirrhosis, and even hepatocellular carcinoma. Although specific serum parameters currently allow rough assessment of metal deficit and excess, the precise quantification of hepatic metal content in liver is presently only possible by different titration or staining techniques of biopsy specimens. Recently, novel innovative metal imaging techniques were developed that are on the way to replace these traditional methods. In the present review, we summarize the function of different trace elements in liver health and disease and discuss the present knowledge on how quantitative biometal imaging techniques such as synchrotron X-ray fluorescence microscopy, secondary ion mass spectrometry, and laser ablation inductively coupled plasma mass spectrometry enrich diagnostics in the detection and quantification of hepatic metal disorders. We will further discuss sample preparation, sensitivity, spatial resolution, specificity, quantification strategies, and potential future applications of metal bioimaging in experimental research and clinical daily routine. © 2015 Wiley Periodicals, Inc. Mass Spec Rev 35:666-686, 2016.

Chronic exposure to low levels of aluminum alters cerebral cell signaling in response to acute MPTP administration

Two-month-old male B/6C3F1 mice were treated for 10 weeks with 100 μM aluminum lactate (Al) in drinking water. This dose of Al did not alter body weight, and there was no evidence of systemic toxicity. The degree of phosphorylation of several kinases which lead to transcription factor activation (reflecting the extent of their activation) was studied. The proportion of extracellular signal-regulated kinase (ERK) that was activated was depressed in cortex but not in the hippocampus following treatment but c-Jun N-terminal kinase (JNK), p38, IκB phosphorylation was unaltered in either tissue. Treatment of mice with 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine (MPTP) alone produced no significant changes in the degree of activation of any transcription factor studied. When MPTP dosing had been preceded by extended exposure to low levels of Al in drinking water, ERK activation was profoundly depressed in cortex and hippocampus, whereas JNK in hippocampus and IκB in cortex were greatly elevated. These changes consequent to exposure to both Al and MPTP were accompanied by an increase in NF-κB in both regions, whereas AP-1 was elevated in the hippocampus alone. Neither agent alone modulated AP-1 or NF-κB. Thus a synergistic interaction occurred between the toxicants. This interaction tended to promote the functioning of a kinase largely associated with inflammation and to depress that of ERK, which is associated with maintenance of cell survival. It is concluded that exposure to levels of Al with no evident toxicity can worsen the response to an acute challenge with MPTP. Al treatment alone was able to increase striatal 3,4-dihydroxyphenylacetic acid levels, suggesting an elevation of the rate of dopamine turnover in the striatum. However, no interaction in alteration of monoamine levels was found between Al and MPTP.

Evaluated the adverse effects of cadmium and aluminum via drinking water to kidney disease patients: Application of a novel solid phase microextraction method

In present study aluminum (Al) and cadmium (Cd) were determined in ground water samples and assesses human health risks associated with elevated concentrations of toxic metals in dissolved form, using a novel solid phase microextraction (SPμE). Ground water sample (n=200) and biological sample (blood) of patients having chronic kidney disorders (CKD) along with healthy control subjects of same area (southern part of Pakistan) were collected. A simple system, including the micropipette tip packed with modified ionic liquid-activated carbon cloth (IL-ACC) coated with 8-hydroxyqunilone (8-HQ) attached to syringe. The analytes in water and acid digested blood samples were manually drawn for 2-10 cycles (drawing/discharging) at different pH range. The analytes sorbed on coated ACC were then desorbed with 2.0molL(-1) HNO3 in ethanol by drawing/discharging cycles for 1-5 times. The concentration of extracted analytes was determined by electrothermal atomic absorption spectrometer. The influence of different variables on the extraction efficiency of Cd and Al, were optimized. The Al and Cd concentrations in groundwater were found to be elevated than recommended limits by the World Health Organization. The urinary N-acetyl-h-glucosaminidase values were significantly higher in CKD patients as compared to refrent subjects (p<0.001). The significant variation in levels of Cd and Al were observed in blood samples of CKD patients than referents subjects (p<0.01). The strong positive correlation among Al and Cd levels in groundwater versus blood samples of CKD patients (r=0.82-0.85) p<0.01) was observed than those values calculated for referent subjects (r=0.425-0.536).

Reduction of adult hippocampal neurogenesis is amplified by aluminum exposure in a model of type 2 diabetes

In this study, we investigated the effects of chronic aluminum (Al) exposure for 10 weeks on cell proliferation and neuroblast differentiation in the hippocampus of type 2 diabetic rats. Six-week-old Zucker diabetic fatty (ZDF) and Zucker lean control (ZLC) rats were selected and randomly divided into Al- and non-Al-groups. Al was administered via drinking water for 10 weeks, after which the animals were sacrificed at 16 weeks of age. ZDF rats in both Al- and non-Al-groups showed increases in body weight and blood glucose levels compared to ZLC rats. Al exposure did not significantly affect body weight, blood glucose levels or pancreatic β-cells and morphology of the pancreas in either ZLC or ZDF rats. However, exposure to Al reduced cell proliferation and neuroblast differentiation in both ZLC and ZDF rats. Exposure to Al resulted in poor development of the dendritic processes of neuroblasts in both ZLC and ZDF rats. Furthermore, onset and continuation of diabetes reduced cell proliferation and neuroblast differentiation, and Al exposure amplified reduction of these parameters. These results suggest that Al exposure via drinking water aggravates the impairment in hippocampal neurogenesis that is typically observed in type 2 diabetic animals.

Correlation of cadmium and aluminum in blood samples of kidney disorder patients with drinking water and tobacco smoking: related health risk

The combined exposure to aluminum (Al) and cadmium (Cd) causes more pronounced adverse health effects on humans. The kidneys are the main organs affected by internal exposure to Cd and Al via food and non-food items. The objective of present study was to measure the Al and Cd concentrations in cigarettes tobacco (branded and non-branded) and drinking water (domestic treated, ground and lake water) samples in southern part of Pakistan, to assess the risk due to ingestion of water and inhalation of cigarettes smoke containing high concentrations of both elements. The study population (kidney disorder and healthy) divided into two group based on consuming lake and ground water, while smoking non-branded cigarette as exposed, while drinking domestic treated water and smoking branded cigarette as non-exposed. Electrothermal atomic absorption spectrometry was used to determined Cd and Al concentrations in tobacco, drinking water and blood samples. The resulted data indicated that the levels of Al and Cd in lake and underground water were higher than the permissible limit in drinking water recommended by the World Health Organization. The biochemical parameters of exposed and referent patients, especially urinary N-acetyl-h-glucosaminidase, were used as a biomarkers of kidney disorder. Exposed kidney disorder patients have higher levels of Cd and Al than the exposed referents subjects, while difference was significant when compared to resulted data of non-exposed patients and referents (p = 0.01-0.001). The pearson correlation showed positive correlation between both toxic element concentrations in water, cigarettes versus blood samples of exposed subjects (r = 0.20-0.67 and 0.71-0.82), while lower values were observed for non-exposed subjects (r = 0.123-0.423 and 0.331-0.425), respectively.

Anthropogenic pollutants may increase the incidence of neurodegenerative disease in an aging population

The current world population contains an ever-increasing increased proportion of the elderly. This is due to global improvements in medical care and access to such care. Thus, a growing incidence of age-related neurodegenerative disorders is to be expected. Increased longevity also allows more time for interaction with adverse environmental factors that have the potential exert a gradual pressure, facilitating the onset of organismic aging. Nearly all neurodegenerative disorders have a relatively minor genetic element and a larger idiopathic component. It is likely that some of the unknown factors promoting neurological disease involve the appearance of some deleterious aspects of senescence, elicited prematurely by low but pervasive levels of toxic materials present in the environment. This review considers the nature of such possible toxicants and how they may hasten neurosenescence. An enhanced rate of emergence of normal age-related changes in the brain can lead to increased incidence of those specific neurological disorders where aging is an essential requirement. In addition, some xenobiotic agents appear to have the capability of engendering specific neurodegenerative disorders and some of these are also considered.

Drinking and recreational water-related diseases: a bibliometric analysis (1980-2015)

BACKGROUND

Water - related diseases are worldwide health concern. Microbial contamination and contaminant products in water are a source of disease outbreaks and development of cumulative toxic effects. Ensuring safe water is one of the goals to be achieved at the global level. The aim of this study was to assess publications on drinking and recreational water from a health point of view to understand current problems and future research trends in this field.

METHODS

Scopus, the largest scientific electronic database, was used to retrieve related articles and present the results as bibliometric tables and maps. Search query was modified manually using related terms to maximize accuracy.

RESULTS

A total of 2267 publications were retrieved with an average of 16.82 citations per article. The h-index of retrieved articles was 88. Visual mapping showed that E. coli, diarrhea, cryptosporidiosis, fluoride, arsenic, cancer, chlorine, trihalomethane, and H. pylori were most frequently encountered terms in title and abstract of retrieved articles. The number of articles on water microbiology was a significant (P < 0.01) predictor of worldwide productivity of water - related disease publications. Journal of Water and Health ranked first in number of publications with 136 (6.00 %) articles. The United States of America ranked first in productivity with a total of 623 (27.48 %) articles. Germany (15.44 %), India (16.00 %) and China (20.66 %) had the least international collaboration in water-related disease research. Environmental Protection Agency and Centers for Disease Prevention and Control were among top ten productive institutions. In the top ten cited articles, there were three articles about arsenic, one about aluminum, one about trihalomethane, one about nitrate, one about toxoplasmosis, one about gastroenteritis, and the remaining two articles were general ones.

CONCLUSIONS

There was a linear increase in the number of publications on water - related diseases in the last decade. Arsenic, in drinking water is a serious concern. Cryptosporidiosis and other infectious gastroenteritis remain a major health risk of exposure to contaminated water. Increased number of publications from Asian countries was not associated with a high percentage of international collaboration.

Systematic review of potential health risks posed by pharmaceutical, occupational and consumer exposures to metallic and nanoscale aluminum, aluminum oxides, aluminum hydroxide and its soluble salts

Abstract Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007) . Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of "total Al"assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold. The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al(+3) to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)(+2) and Al(H2O)6 (+3)] that after complexation with O2(•-), generate Al superoxides [Al(O2(•))](H2O5)](+2). Semireduced AlO2(•) radicals deplete mitochondrial Fe and promote generation of H2O2, O2 (•-) and OH(•). Thus, it is the Al(+3)-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates. Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer's disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants. The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances.

Dual blockade of the A1 and A2A adenosine receptor prevents amyloid beta toxicity in neuroblastoma cells exposed to aluminum chloride

In a previous work we have shown that exposure to aluminum (Al) chloride (AlCl3) enhanced the neurotoxicity of the amyloid beta(25-35) fragment (Abeta(25-35)) in neuroblastoma cells and affected the expression of Alzheimer's disease (AD)-related genes. Caffein, a compound endowed with beneficial effects against AD, exerts neuroprotection primarily through its antagonist activity on A2A adenosine receptors (A2AR), although it also inhibits A1Rs with similar potency. Still, studies on the specific involvement of these receptors in neuroprotection in a model of combined neurotoxicity (Abeta(25-35)+AlCl3) are missing. To address this issue, cultured SH-SY5Y cells exposed to Abeta(25-35)+AlCl3 were assessed for cell viability, morphology, intracellular ROS activity and expression of apoptosis-, stress- and AD-related proteins. To define the role of A1R and A2ARs, pretreatment with caffein, specific receptor antagonists (DPCPX or SCH58261) or siRNA-mediated gene knockdown were delivered. Results indicate that AlCl3 treatment exacerbated Abeta(25-35) toxicity, increased ROS production, lipid peroxidation, β-secretase-1 (BACE1) and amyloid precursor protein (APP). Interestingly, SCH58261 successfully prevented toxicity associated to Abeta(25-35) only, whereas pretreatment with both DPCPX and SCH58261 was required to fully avert Abeta(25-35)+AlCl3-induced damage, suggesting that A1Rs might also be critically involved in protection during combined toxicity. The effects of caffein were mimicked by both N-acetyl cysteine, an antioxidant, and desferrioxamine, likely acting through distinct mechanisms. Altogether, our data establish a novel protective function associated with A1R inhibition in the setting of combined Abeta(25-35)+AlCl3 neurotoxicity, and expand our current knowledge on the potential beneficial role of caffein to prevent AD progression in subjects environmentally exposed to aluminum.

Oxidative stress and mitochondrial dysfunction in aluminium neurotoxicity and its amelioration: a review

Aluminium is light weight and toxic metal present ubiquitously on earth which has gained considerable attention due to its neurotoxic effects. The widespread use of products made from or containing aluminium is ensuring its presence in our body. There is prolonged retention of a fraction of aluminium that enters the brain, suggesting its potential for accumulation with repeated exposures. There is no known biological role for aluminium within the body but adverse physiological effects of this metal have been observed in mammals. The generation of oxidative stress may be attributed to its toxic consequences in animals and humans. The oxidative stress has been implicated in pathogenesis of various neurodegenerative conditions including Alzheimer's disease and Parkinson's disease. Though it remains unclear whether oxidative stress is a major cause or merely a consequence of cellular dysfunction associated with neurodegenerative diseases, an accumulating body of evidence implicates that impaired mitochondrial energy production and increased mitochondrial oxidative damage is associated with the pathogenesis of neurodegenerative disorders. Being involved in the production of reactive oxygen species, aluminium may impair mitochondrial bioenergetics and may lead to the generation of oxidative stress. In this review, we have discussed the oxidative stress and mitochondrial dysfunctions occurring in Al neurotoxicity. In addition, the ameliorative measures undertaken in aluminium induced oxidative stress and mitochondrial dysfunctions have also been highlighted.

Investigation of Water Safety in Non-treated Drinking Water with Trace Toxic Metals

The trace toxic metal copper was assayed using mercury immobilized on a carbon nanotube electrode (MCW), with a graphite counter and a reference electrode. In this study, a macro-scale convection motor was interfaced with a MCW three-electrode system, in which a handmade MCW was optimized using cyclic- and square-wave stripping voltammetry. An analytical electrolyte for tap water was used instead of an expensive acid or base ionic solution. Under these conditions, optimum parameters were 0.09 V amplitude, 40 Hz frequency, 0.01 V incremental potential, and a 60-s accumulation time. A diagnostic working curve was obtained from 50.0 to 350 μg/L. At a constant Cu(II) concentration of 10.0 μg/L, the statistical relative standard deviation was 1.78% (RSD, n = 15), the analytical accumulation time was only 60 s, and the analytical detection limit approached 4.6 μg/L (signal/noise = 3). The results were applied to nontreated drinking water. The content of the analyzed copper using 9.0 and 4.0 μg/L standards were 8.68 μg/L and 3.96 μg/L; statistical values R(2) = 0.9987 and R(2) = 0.9534, respectively. This method is applicable to biological diagnostics or food surveys.

Neuroinflammation and copper in Alzheimer's disease

Inflammation is the innate immune response to infection or tissue damage. Initiation of proinflammatory cascades in the central nervous system (CNS) occurs through recognition of danger associated molecular patterns by cognate immune receptors expressed on inflammatory cells and leads to rapid responses to remove the danger stimulus. The presence of activated microglia and astrocytes in the vicinity of amyloid plaques in the brains of Alzheimer's disease (AD) patients and mouse models implicates inflammation as a contributor to AD pathogenesis. Activated microglia play a critical role in amyloid clearance, but chronic deregulation of CNS inflammatory pathways results in secretion of neurotoxic mediators that ultimately contribute to neurodegeneration in AD. Copper (Cu) homeostasis is profoundly affected in AD, and accumulated extracellular Cu drives Aβ aggregation, while intracellular Cu deficiency limits bioavailable Cu required for CNS functions. This review presents an overview of inflammatory events that occur in AD in response to Aβ and highlights recent advances on the role of Cu in modulation of beneficial and detrimental inflammatory responses in AD.

Selective accumulation of aluminum in cerebral arteries in Alzheimer's disease (AD)

Once biologically available aluminum bypasses gastrointestinal and blood-brain barriers, this environmentally-abundant neurotoxin has an exceedingly high affinity for the large pyramidal neurons of the human brain hippocampus. This same anatomical region of the brain is also targeted by the earliest evidence of Alzheimer's disease (AD) neuropathology. The mechanism for the selective targeting and transport of aluminum into the hippocampus of the human brain is not well understood. In an effort to improve our understanding of a pathological aluminum entry system into the brain, this study examined the aluminum content of 8 arteries that supply blood to the hippocampus, including the aorta and several cerebral arteries. In contrast to age-matched controls, in AD patients we found a gradient of increasing aluminum concentration from the aorta to the posterior cerebral artery that supplies blood to the hippocampus. Primary cultures of human brain endothelial cells were found to have an extremely high affinity for aluminum when compared to other types of brain cells. Together, these results suggest for the first time that endothelial cells that line the cerebral vasculature may have biochemical attributes conducive to binding and targeting aluminum to selective anatomical regions of the brain, such as the hippocampus, with potential downstream pro-inflammatory and pathogenic consequences.

Low concentrations of copper in drinking water increase AP-1 binding in the brain

Copper (Cu) in trace amounts is essential for biological organisms. However, dysregulation of the redox-active metal has been implicated in different neurological disorders such as Wilson’s, Menkes’, Alzheimer’s, and Parkinson’s diseases. Since many households use Cu tubing in the plumbing system, and corrosion causes the metal to leach into the drinking water, there may be adverse effects on the central nervous system connected with low-level chronic exposure. The present study demonstrates that treatment with a biologically relevant concentration of Cu for 3 months significantly increases activation of the redox-modulated transcription factor AP-1 in mouse brains. This was independent of an upstream kinase indicated in AP-1 activation. Another redox-active transcription factor, NF-κB, was not significantly modified by the Cu exposure. These results indicate that the effect of Cu on AP-1 is unique and may involve direct modulation of DNA binding.

Trace element, antioxidant activity, and lipid peroxidation levels in brain cortex of gerbils after cerebral ischemic injury

Proper trace element level and antioxidant enzyme activity are crucial for the brain in maintaining normal neurological functions. To our knowledge, alteration of lipid peroxidation status, trace element level, and antioxidant activity in the homogenates of brain cortex after cerebral ischemia in gerbil, however, has not been investigated so far. Male Mongolian gerbils were divided into control and ischemic subjects. Cerebral ischemia was induced by occlusion of the right middle cerebral artery and right common carotid artery for 1 h. Experimental results showed that a significant increase (P < 0.01) of the malondialdehyde level was found in the ischemic brain as compared with the control group. Trace element analysis indicated that a remarkable elevation (P < 0.01) of the level of iron (Fe), chromium (Cr), and a statistical decrease of selenium (Se) and zinc (Zn) (P < 0.05) concentration were observed in the ischemic brain as compared with the control subject. No significant change (P > 0.05) of the copper (Cu) level was found in both experimental groups. Additionally, antioxidant activity of superoxide dismutase (P < 0.01) and catalase (P < 0.05) was significantly decreased in the ischemic brain as compared with the control subject. Taking all results together, it is conceivable to manifest the experimental findings that cerebral ischemia not only may result in an enhanced oxidative stress but also may lead to further oxidative injury. Moreover, disturbance of trace element level combined with declined antioxidant activity seems to play a significant role in responsible for the etiology of cerebral ischemia.

How aluminum, an intracellular ROS generator promotes hepatic and neurological diseases: the metabolic tale

Metal pollutants are a global health risk due to their ability to contribute to a variety of diseases. Aluminum (Al), a ubiquitous environmental contaminant is implicated in anemia, osteomalacia, hepatic disorder, and neurological disorder. In this review, we outline how this intracellular generator of reactive oxygen species (ROS) triggers a metabolic shift towards lipogenesis in astrocytes and hepatocytes. This Al-evoked phenomenon is coupled to diminished mitochondrial activity, anerobiosis, and the channeling of α-ketoacids towards anti-oxidant defense. The resulting metabolic reconfiguration leads to fat accumulation and a reduction in ATP synthesis, characteristics that are common to numerous medical disorders. Hence, the ability of Al toxicity to create an oxidative environment promotes dysfunctional metabolic processes in astrocytes and hepatocytes. These molecular events triggered by Al-induced ROS production are the potential mediators of brain and liver disorders.

Toxicity of copper salts is dependent on solubility profile and cell type tested

Copper (Cu) is considered an essential metal for living organisms. However, disruption of Cu homeostasis is toxic and can lead to disorders such as Menkes and Wilson's diseases. The brain appears to be a vulnerable target organ. This study investigated the toxicity of Cu based on its solubility profile and cell type tested. Human A-172 (glioblastoma), SK-N-SH (neuroblastoma) and CCF-STTG1 (astrocytoma) cells were assessed after exposure to different concentrations (0.5-500μM) of copper sulfate (CuSO4) or copper (II) oxide (CuO). Since Cu is a redox active transition metal, we hypothesized that oxidative stress would be the main mechanism underlying cell toxicity. Therefore, cell viability was correlated with the extent of reactive oxygen species (ROS) formation. Cell viability decreased at the higher concentrations of the Cu salts and CuO was more toxic compared to CuSO4. The astrocytoma and glioblastoma cells were more vulnerable compared to the neuronal cells. Furthermore, it appears that oxidative stress only partially accounts for Cu-induced cell toxicity. Further studies are needed to better understand the unique susceptibility of glial cells and determine the physicochemical properties of insoluble Cu which accounts for its enhanced toxicity.