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Cancer stem cells (CSCs) and cells in a cancer stem cell-like (CSCL) state have proven to be responsible for tumor initiation, growth, and relapse in Prostate Cancer (PCa) and other cancers; therefore, new strategies are being developed to target such cellular populations. TLR3 activation-based immunotherapy using Polyinosinic:Polycytidylic acid (PIC) has been proposed to be used as a concomitant strategy to first-line treatment. This strategy is based on the induction of apoptosis and an inflammatory response in tumor cells. In combination with retinoids like 9cRA, this treatment can induce CSCs differentiation and apoptosis. A limitation in the use of this combination is the common decreased expression of TLR3 and its main positive regulator p53. observed in many patients suffering of different cancer types such as PCa. Importantly, human exposure to certain toxicants, such as iAs, not only has proven to enrich CSCs population in an in vitro model of human epithelial prostate cells, but additionally, it can also lead to a decreased p53, TLR3 and RA receptor (RARβ), expression/activation and thus hinder this treatment efficacy. Therefore, here we point out the relevance of evaluating the TLR3 and P53 status in PCa patients before starting an immunotherapy based on the use of PIC +9cRA to determine whether they will be responsive to treatment. Additionally, the use of strategies to overcome the lower TLR3, RARβ or p53 expression in PCa patients, like the inclusion of drugs that increase p53 expression, is encouraged, to potentiate the use of PIC+RA based immunotherapy in these patients.

Parkinson's disease (PD) is a progressive motor disease of unknown etiology. Although neuroprotective ability of endogenous bile acid, tauroursodeoxycholic acid (TUDCA), shown in various diseases, including an acute model of PD,the potential therapeutic role of TUDCA in progressive models of PD that exhibit all aspects of PD has not been elucidated. In the present study, mice were assigned to one of four treatment groups: (1) Probenecid (PROB); (2) TUDCA, (3) MPTP + PROB (MPTPp); and (3) TUDCA + MPTPp.

Background Iron nanoparticles, mainly in magnetite phase (Fe3O4 NPs), are released to the environment in areas with high traffic density and braking frequency. Fe3O4 NPs were found in postmortem human brains and are assumed to get directly into the brain through the olfactory nerve. However, these pollution-derived NPs may also translocate from the lungs to the bloodstream and then, through the blood-brain barrier (BBB), into the brain inducing oxidative and inflammatory responses that contribute to neurodegeneration. Objective To describe the interaction and toxicity of pollution-derived Fe3O4 NPs on primary rat brain microvascular endothelial cells (rBMECs), main constituents of in vitro BBB models. Methods Synthetic bare Fe3O4 NPs that mimic the environmental ones (miFe3O4) were synthesized by co-precipitation and characterized using complementary techniques. The rBMECs were cultured in Transwell® plates. The NPs-cell interaction was evaluated through transmission electron microscopy and standard colorimetric in vitro assays. Results The miFe3O4 NPs, with a mean diameter of 8.45±0.14 nm, presented both magnetite and maghemite phases, and showed super-paramagnetic properties. Results suggest that miFe3O4 NPs are internalized by rBMECs through endocytosis and that they are able to cross the cells monolayer. The lowest miFe3O4 NPs concentration tested induced mid cytotoxicity in terms of 1) membrane integrity (LDH release) and 2) metabolic activity (MTS transformation). Conclusion Pollution-derived Fe3O4 NPs may interact and cross the microvascular endothelial cells forming the BBB and cause biological damage.

A therapeutic strategy for prostate cancer (PCa) involves the use of 9-cis-retinoic acid (9cRA) to induce cancer stem cells (CSCs) differentiation and apoptosis. Polyinosinic:polycytidylic acid (PIC) is a Toll-like receptor 3 (TLR3) agonist that induces tumor cells apoptosis after activation. PIC+9cRA combination activates retinoic acid receptor β (RARβ) re-expression, leading to CSC differentiation and growth arrest. Since inorganic arsenic (iAs) targets prostatic stem cells (SCs), we hypothesized that arsenic-transformed SCs (As-CSCs) show an impaired TLR3-associated anti-tumor pathway and, therefore, are unresponsive to PIC activation. We evaluated TLR3-mediated activation of anti-tumor pathway based in RARβ expression, on As-CSC and iAs-transformed epithelial cells (CAsE-PE). As-CSCs and CAsE-PE showed lower TLR3 and RARβ basal expression compared to their respective isogenic controls WPE-Stem and RWPE-1. Also, iAs transformants showed reduced expression of mediators in TLR3 pathway. Importantly, As-CSCs were irresponsive to PIC+9cRA in terms of increased RARβ and decreased SC-markers expression, while CAsE-PE, a heterogeneous cell line having a small SC population, were partially responsive. These observations indicate that iAs can impair TLR3 expression and anti-tumor pathway activated by PIC+9cRA in SCs and prostatic epithelial cells. These findings suggest that TLR3-activation based therapy may be an ineffective therapeutic alternative for iAs-associated PCa.

Background: Iron nanoparticles, mainly in magnetite phase (Fe3O4 NPs), are released to the environment in areas with high traffic density and braking frequency. Fe3O4 NPs were found in postmortem human brains and are assumed to get directly into the brain through the olfactory nerve. However, these pollution-derived NPs may also translocate from the lungs to the bloodstream and then, through the blood-brain barrier (BBB), into the brain inducing oxidative and inflammatory responses that contribute to neurodegeneration. Objective: To describe the interaction and toxicity of pollution-derived Fe3O4 NPs on primary rat brain microvascular endothelial cells (rBMECs), main constituents of in vitro BBB models. Methods: Synthetic bare Fe3O4 NPs that mimic the environmental ones (miFe3O4) were synthesized by co-precipitation and characterized using complementary techniques. The rBMECs were cultured in Transwell® plates. The NPs-cell interaction was evaluated through transmission electron microscopy and standard colorimetric in vitro assays. Results: The miFe3O4 NPs, with a mean diameter of 8.45 ± 0.14 nm, presented both magnetite and maghemite phases, and showed super-paramagnetic properties. Results suggest that miFe3O4 NPs are internalized by rBMECs through endocytosis and that they are able to cross the cells monolayer. The lowest miFe3O4 NPs concentration tested induced mid cytotoxicity in terms of 1) membrane integrity (LDH release) and 2) metabolic activity (MTS transformation). Conclusion: Pollution-derived Fe3O4 NPs may interact and cross the microvascular endothelial cells forming the BBB and cause biological damage.

Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic low-grade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders.

Graphene-based nanomaterials hold the potential to be used in a wide variety of applications, including biomedical devices. Pristine graphene (PG) is an un-functionalized, defect-free type of graphene that could be used as a material for neural interfacing. However, the neurotoxic effects of PG, particularly to the blood-brain barrier (BBB), have not been fully studied. The BBB separates the brain tissue from the circulating substances in the blood and is essential to maintain the brain homeostasis. The principal components of the BBB are brain microvascular endothelial cells (BMVECs), which maintain a protectively low permeability due to the expression of tight junction proteins. Here we analyzed the effects of PG on BMVECs in an in vitro model of the BBB. BMVECs were treated with PG at 0, 10, 50 and 100 μg/mL for 24 hours and viability and functional analyses of BBB integrity were performed. PG increased lactate dehydrogenase release at 50 and 100 μg/mL, suggesting the induction of necrosis. Surprisingly, 2,3,-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)-carbonyl]-2H-tetrazolium (XTT) conversion was increased at 10 and 50 μg/mL. In contrast, XTT conversion was decreased at 100 μg/mL, suggesting the induction of cell death. In addition, 100 μg/mL PG increased DNA fragmentation, suggesting induction of apoptosis. At the same time, 50 and 100 μg/mL of PG increased the endothelial permeability, which corresponded with a decrease in the expression of the tight junction protein occludin at 100 μg/mL. In conclusion, these results suggest that PG negatively affects the viability and function of the BBB endothelial cells in vitro.

Long-term exposure to inorganic arsenic (iAs) through drinking water has been associated with cognitive impairment in children and adults; however, the related pathogenic mechanisms have not been completely described. Increased or chronic inflammation in the brain is linked to impaired cognition and neurodegeneration; iAs induces strong inflammatory responses in several cells, but this effect has been poorly evaluated in central nervous system (CNS) cells. Because astrocytes are the most abundant cells in the CNS and play a critical role in brain homeostasis, including regulation of the inflammatory response, any functional impairment in them can be deleterious for the brain. We propose that iAs could induce cognitive impairment through inflammatory response activation in astrocytes. In the present work, rat cortical astrocytes were acutely exposed in vitro to the monomethylated metabolite of iAs (MMAIII), which accumulates in glial cells without compromising cell viability. MMAIII LD50 in astrocytes was 10.52 μM, however, exposure to sub-toxic MMAIII concentrations (50–1000 nM) significantly increased IL-1β, IL-6, TNF-α, COX-2, and MIF-1 gene expression. These effects were consistent with amyloid precursor protein (APP) and β-secretase (BACE-1) increased gene expression, mainly for those MMAIII concentrations that also induced TNF-α over-expression. Other effects of MMAIII on cortical astrocytes included increased proliferative and metabolic activity. All tested MMAIII concentrations led to an inhibition of intracellular lactate dehydrogenase (LDH) activity. Results suggest that MMAIII induces important metabolic and functional changes in astrocytes that may affect brain homeostasis and that inflammation may play a major role in cognitive impairment-related pathogenicity in As-exposed populations.

Al-doped HfO2 nanoparticles were prepared at room-temperature using a novel one-step, straightforward, high-yield, efficient and green process. It includes a mechanically activated metathesis reaction that promotes the direct crystallization of cubic HfO2 (c-HfO2) in milling. Al-cation was used as dopant, achieving c-HfO2 stabilization at low content (5% mol). The c-HfO2 is stable up to 380 °C without exhibiting transformation from the cubic to monoclinic polymorph. The c-HfO2 showed spherical-like morphology with diameter below 7 nm. Human Prostate Epithelial Cells (HPrEC) were used to evaluate nanoparticles toxicity. Cells viability and survival were determined performing MTS and colony formation assays. Nanoparticles were found harmless for cells metabolic activity at concentrations up to 1000 μg/mL. A decrease of ~30% on HPrEC plating efficiency was observed at the highest concentration.

Traumatic brain injury (TBI) occurs when external mechanical forces induce brain damage as result of impact, penetration or rapid acceleration/deceleration that causes deformation of brain tissue. Depending on its severity, TBI can be classified as mild, moderate or severe and can lead to blood-brain barrier (BBB) dysfunction. In the present study, we evaluated the effects of uniaxial high-speed stretch (HSS) at 0, 5, 10 and 15% on a pure culture of primary rat brain endothelial cells as an in vitro model of TBI to the BBB. LDH release, viability and apoptosis analysis, expression of tight junction proteins and endothelial permeability were evaluated 24 h after a single stretch episode. HSS slightly increased cell death and apoptosis at 10 and 15%, while LDH release was increased only at 15% stretch. Occludin expression was increased at 10% stretch, while claudin-5 expression was increased at 5% stretch, which also decreased the endothelial permeability. In summary, 15% HSS induced low levels of cell death, consistent with mild TBI and very low percentages of HSS (5%) enhanced the BBB properties, promoting the formation of a stronger barrier. These data support the use of 15% HSS as valuable tool in the study of mild TBI to the BBB in vitro.

Traumatic brain injury (TBI) is one of the major causes of disability in the USA. It occurs when external mechanical forces induce brain damage that causes deformation of brain tissue. TBI is also associated with alterations of the blood-brain barrier (BBB). Using primary rat brain microvascular endothelial cells as an in vitro BBB model, the effects of biaxial stretch were characterized at 5, 10, 15, 25, and 50% deformation using a commercially available system. The results were compared to the effects of mild and moderate TBI in vivo, induced by the weight-drop method in mice. In vitro, live/dead cells, lactate dehydrogenase (LDH) release, caspase 3/7 staining, and tight junction (TJ) protein expression were evaluated 24 h after a single stretch episode. In vivo, Evans blue extravasation, serum levels of S100β, and TJ protein expression were evaluated. Stretch induced a deformation-dependent increase in LDH release, cell death, and activation of caspase 3/7, suggesting the induction of apoptosis. Interestingly, low magnitudes of deformation increased the expression of TJ proteins, likely in an attempt to compensate for stretch damage. High magnitudes of deformation decreased the expression of TJ proteins, suggesting that the damage was too severe to counteract. In vivo, mild TBI did not affect BBB permeability or the expression of TJ proteins. However, moderate TBI significantly increased BBB permeability and decreased the expression of these proteins, similar to the results obtained with a high magnitude deformation. These data support the use biaxial stretch as valuable tool in the study of TBI in vitro.

UROtsa cells have been accepted as a model to study carcinogenicity mechanisms of arsenic-associated human bladder cancer. In vitro continuous exposure to monomethylarsonous acid (MMAIII), leads UROtsa cells to commit to malignant transformation. In this process, NF-κβ-associated inflammatory response seems to play an important role since this transcription factor activates some minutes after cells are exposed in vitro to MMAIII and keeps activated during the cellular malignant transformation. It is known that a slight decrease in the protein phosphatase and tensin homologue (PTEN) gene expression is enough for some cells to become malignantly transformed. Interestingly, this tumor suppressor has been proven to be negatively regulated by NF-κβ through binding to its gene promoter. Based on these observations we propose that NF-κβ may be involved in arsenic associated carcinogenesis through the negative regulation of PTEN gene expression. Changes in PTEN expression and the binding of p50 NF-κβ subunit to PTEN promoter were evaluated in UROtsa cells exposed for 4, 12, 20, or 24 wk to 50nM MMAIII. Results showed that MMAIII induced a significant decrease in PTEN expression around 20 wk exposure to MMAIII,which correlated with increased binding of p50 subunit to the PTEN promoter. Consistent with these results, ChIP assays also showed a significant decrease in H3 acetylation (H3ac) but an increase in the repression marks H3k9me3 and H327me3 in PTEN promoter when compared with not treated cells. These results suggest that the activation of NF-κβ by MMAIII may participate in UROtsa cells malignant transformation through the negative regulation of PTEN expression involving p50 homodimers-mediated chromatin remodeling around the PTEN promoter.

Bladder cancer has been associated with chronic arsenic exposure. Monomethylarsonous acid [MMA(III)] is a metabolite of inorganic arsenic and has been shown to transform an immortalized urothelial cell line (UROtsa) at concentrations 20-fold less than arsenite. MMA(III) was used as a model arsenical to examine the mechanisms of arsenical-induced transformation of urothelium. A microarray analysis was performed to assess the transcriptional changes in UROtsa during the critical window of chronic 50 nM MMA(III) exposure that leads to transformation at three months of exposure. The analysis revealed only minor changes in gene expression at one and two months of exposure, contrasting with substantial changes observed at three months of exposure. The gene expression changes at three months were analyzed showing distinct alterations in biological processes and pathways such as a response to oxidative stress, enhanced cell proliferation, anti-apoptosis, MAPK signaling, as well as inflammation. Twelve genes selected as markers of these particular biological processes were used to validate the microarray and these genes showed a time-dependent changes at one and two months of exposure, with the most substantial changes occurring at three months of exposure. These results indicate that there is a strong association between the acquired phenotypic changes that occur with chronic MMA(III) exposure and the observed gene expression patterns that are indicative of a malignant transformation. Although the substantial changes that occur at three months of exposure may be a consequence of transformation, there are common occurrences of altered biological processes between the first two months of exposure and the third, which may be pivotal in driving transformation.

The association between chronic human exposure to arsenicals and bladder cancer development is well recognized; however, the underlying molecular mechanisms have not been fully determined. We propose that inflammatory responses can play a pathogenic role in arsenic-related bladder carcinogenesis. In previous studies, it was demonstrated that chronic exposure to 50 nM monomethylarsenous acid [MMA(III)] leads to malignant transformation of an immortalized model of urothelial cells (UROtsa), with only 3 mo of exposure necessary to trigger the transformation-related changes. In the three-month window of exposure, the cells over-expressed pro-inflammatory cytokines (IL-1β, IL-6 and IL-8), consistent with the sustained activation of NFKβ and AP1/c-jun, ERK2, and STAT3. IL-8 was over-expressed within hours after exposure to MMA(III), and sustained over-expression was observed during chronic exposure. In this study, we profiled IL-8 expression in UROtsa cells exposed to 50 nM MMA(III) for 1 to 5 mo. IL-8 expression was increased mainly in cells after 3 mo MMA(III) exposure, and its production was also found increased in tumors derived from these cells after heterotransplantation in SCID mice. UROtsa cells do express both receptors, CXCR1 and CXCR2, suggesting that autocrine cell activation could be important in cell transformation. Supporting this observation and consistent with IL-8 over-expression, CXCR1 internalization was significantly increased after three months of exposure to MMA(III). The expression of MMP-9, cyclin D1, bcl-2, and VGEF was significantly increased in cells exposed to MMA(III) for 3 mo, but these mitogen-activated kinases were significantly decreased after IL-8 gene silencing, together with a decrease in cell proliferation rate and in anchorage-independent colony formation. These results suggest a relevant role of IL-8 in MMA(III)-induced UROtsa cell transformation.

Cardiovascular disease (CVD) and type 2 diabetes (T2D) are increasing worldwide. This is mainly due to an unhealthy nutrition, implying that variation in CVD risk may be due to variation in the capacity to manage a nutritional load. We examined the genomic basis of postprandial metabolism. Our main purpose was to introduce the GEMM Family Study (Genetics of Metabolic Diseases in Mexico) as a multi-center study carrying out an ongoing recruitment of healthy urban adults. Each participant received a mixed meal challenge and provided a 5-hours’ time course series of blood, buffy coat specimens for DNA isolation, and adipose tissue (ADT)/skeletal muscle (SKM) biopsies at fasting and 3 h after the meal. A comprehensive profiling, including metabolomic signatures in blood and transcriptomic and proteomic profiling in SKM and ADT, was performed to describe tendencies for variation in postprandial response. Our data generation methods showed preliminary trends indicating that by characterizing the dynamic properties of biomarkers with metabolic activity and analyzing multi-OMICS data it could be possible, with this methodology and research design, to identify early trends for molecular biology systems and genes involved in the fasted and fed states.

Arsenic (As) is a worldwide naturally occurring metalloid. Human chronic exposure to inorganic As compounds (iAs), which are at the top of hazardous substances (ATSDR, 2013), is associated with different diseases including cancer and non- cancerous diseases. The neurotoxic effects of iAs and its methylated metabolites have been demonstrated in exposed populations and experimental models. Impaired cognitive abilities have been described in children and adults chronically exposed to iAs through drinking water. Even though different association studies failed to demonstrate that As causes neurodegenerative diseases, several toxicity mechanisms of iAs parallel those mechanisms associated with neurodegeneration, including oxidative stress and inflammation, impaired protein degradation, autophagy, and intracellular accumulation, endoplasmic reticulum stress, and mitochondrial dysfunction. Additionally, different reports have shown that specifically in brain tissue, iAs and its metabolites induce hyper-phosphorylation of the tau protein and over-regulation of the amyloid precursor protein, impaired neurotransmitters synthesis and synaptic transmission, increased glutamate receptors activation, and decreased glutamate transporters expression. Interestingly, increased and sustained pro-inflammatory responses mediated by cytokines and related factors, seems to be the triggering factor for all of such cellular pathological effects. Therefore, this review proposes that iAs-associated cognitive impairment could be the result of the activation of pro-inflammatory responses in the brain tissue, which also may favor neurodegeneration or increase the risk for neurodegenerative diseases in exposed human populations.

The presence of furan in common cooked foods along with evidence from experimental studies that lifetime exposure to furan causes liver tumors in rats and mice has caused concern to regulatory public health agencies worldwide; however, the mechanisms of the furan-induced hepatocarcinogenicity remain unclear. The goal of the present study was to investigate whether or not long-term exposure to furan causes epigenetic alterations in rat liver. Treating of male Fisher 344 rats by gavage 5 days per week with 0, 0.92, 2.0, or 4.4 mg furan/kg body weight (bw)/day resulted in dose- and time-dependent epigenetic changes consisting of alterations in DNA methylation and histone lysine methylation and acetylation, altered expression of chromatin modifying genes, and gene-specific methylation. Specifically, exposure to furan at doses 0.92, 2.0, or 4.4 mg furan/kg bw/day caused global DNA demethylation after 360 days of treatment. There was also a sustained decrease in the levels of histone H3 lysine 9 and H4 lysine 20 trimethylation after 180 and 360 days of furan exposure, and a marked reduction of histone H3 lysine 9 and H3 lysine 56 acetylation after 360 days at 4.4 mg/kg bw/day. These histone modification changes were accompanied by a reduced expression of Suv39h1, Prdm2, and Suv4-20h2 histone methyltransferases and Ep300 and Kat2a histone acetyltransferases. Additionally, furan at 2.0 and 4.4 mg/kg bw/day induced hypermethylation-dependent down-regulation of the Rassf1a gene in the livers after 180 and 360 days. These findings indicate possible involvement of dose- and time-dependent epigenetic modifications in the furan hepatotoxicity and carcinogenicity. Key words: Furan; liver; rat; epigenetic changes.

Human exposure to arsenicals is associated with inflammatory-related diseases including different kinds of cancer as well as non-cancerous diseases like neuro-degenerative diseases, atherosclerosis, hypertension, and diabetes. Interindividual susceptibility has been mainly addressed by evaluating the role of genetic polymorphism in metabolic enzymes in inorganic arsenic (iAs) metabolism. Glutathione S-transferase omega 1-1 (GSTO1-1), which had been associated with iAs metabolism, is also known to participate in inflammatory and apoptotic cellular responses. The polymorphism A140D of GSTO1-1 has been not only associated with distinct urinary profile of arsenic metabolites in populations chronically exposed to iAs in drinking water, but also with higher risk of childhood leukemia and lung disease in non-exposed populations, suggesting that GSTO1-1 involvement in other physiologic processes different from toxics metabolism could be more relevant than is thought. We evaluated the association of the presence of A140D and E208K polymorphisms of GSTO1-1 gene with the expression of genes codifying for proteins involved in the inflammatory and apoptotic response in a human population chronically exposed to iAs through drinking water. A140D polymorphism was associated with higher expression of genes codifying for IL-8 and Apaf-1 mainly in heterozygous individuals, while E208K was associated with higher expression of IL-8 and TGF-β gene, in both cases, the association was independently of iAs exposure level; however, the exposure to iAs increased slightly but significantly the influence of A140D and E208K polymorphisms on such genes expression. These results suggest an important role of GSTO1-1 in the inflammatory response and the apoptotic process and indicate that A140D and E208K polymorphisms could increase the risk of developing inflammatory and apoptosis-related diseases in As-exposed populations.

Human bladder cancer has been associated with chronic exposure to arsenic. Chronic exposure of an immortalized non-tumorigenic urothelial cell line (UROtsa cells) to arsenicals has transformed these cells to a malignant phenotype, but the involved mechanisms are not fully understood. Chronic inflammation has been linked with cancer development mainly because many pro-inflammatory cytokines, growth factors as well as angiogenic chemokines have been found in tumors. In this study the chronology of inflammatory cytokines production was profiled in UROtsa cells chronically exposed to the toxic arsenic metabolite, monomethylarsonous acid [50 nM MMA(III)] to know the role of inflammation in cell transformation. Acute 50 nM MMA(III) exposure induced over-production of many pro-inflammatory cytokines as soon as 12 h after acute exposure. The same cytokines remain over-regulated after chronic exposure to 50 nM MMA(III), especially after 3 mo exposure. At 3 mo exposure the sustained production of cytokines like IL-1, IL-6, IL-8 and TNF is coincident with the appearance of characteristics associated with cell transformation seen in other arsenic-UROtsa studies. The sustained and increased activation of NFkappaB and c-Jun is also present along the transformation process and the phosphorylated proteins p38 MAPK and ERK 1/2 are increased also through the time line. Taken together these results support the notion that chronic inflammation is associated within MMA(III)-induced cell transformation and may act as a promoting factor in UROtsa cell transformation.

Inorganic arsenic (iAs) contamination of drinking water is a worldwide problem associated with an increased risk for the development of various types of cancer and noncancerous damage. In vitro studies have suggested that iAs can modulate the activity of macrophages producing an over-expression of cyclooxygenase-2 (COX-2) and resulting in an increase in prostaglandin E(2) (PGE(2)) concentrations in endothelial cells. These effects may lead to an in vivo enhancement of inflammatory and pain responses. Our aim was to determine the effect of a single dose of arsenic or subchronic exposure to arsenic on pain behavior and tissue inflammation in rats. Rats were given a single dose of sodium arsenite (0.1, 1 and 10 mg/kg i.p.) or submitted to subchronic exposure to arsenic added to the drinking water for 4 weeks (0.1, 1, 10 and 100 ppm). Inflammatory pain was assessed by using the formalin and tail-flick tests, while inflammation was evaluated with the carrageenan model. Arsenite did not induce pain or significant inflammation by itself. In contrast, arsenite in both single dose administration and subchronic exposure increased not only the inflammatory process and the underlying hyperalgesic pain, but also induced a decrease in the pain threshold. Alterations in pain processing were dependent on the arsenic dose and the length of exposure, and the underlying mechanism involved an increased release of local PGE(2). These results suggest that inorganic arsenic exposure enhances pain perception and exacerbates the pathological state of inflammatory diseases.

Chronic exposure to toxicants alters immune function that can affect the ability of the host to mount a response to infection. Giardiasis is a gastrointestinal disease in which subtle alteration in immunity of the host can transform the normal acute infection into a chronic one. In this work we used a murine giardiasis model to evaluate the effect of chronic oral intoxication with sodium arsenite on the characteristics of giardiasis. BALB/c mice were intoxicated during 45 days with water containing 50, 125 or 250 microg/mL sodium arsenite. Each group was then inoculated with G. muris cysts. Cysts excreted in the feces were isolated and quantified. The toxic effect of arsenic on intestinal trophozoites was evaluated using G. lamblia trophozoites cultured in vitro with different arsenic concentrations, corresponding to equivalent concentrations of arsenic found in the gut lumen of intoxicated mice. Mice intoxicated with 125 and 250 microg/mL of sodium arsenite and infected with G. muris cysts displayed a shorter period of cysts excretion and were resistant to secondary infection with the parasite. In vitro studies showed that G. lamblia trophozoites were able to grow in presence of high sodium arsenite concentrations, suggesting the absence of a direct toxic effect on the parasite in the gut. Since a longer period of Giardia cysts excretion is associated with suppression of the immune system, the earlier clearance of primary G. muris infection in intoxicated mice suggests the induction of an immune modification that leads to an improved ability of mice to overcome the infection.

Despite the relevance of immune responses in cancer development, little is known about arsenite-induced apoptosis on different immune effectors cells. In this work, we determined the effect of in vitro exposure to sodium arsenite on apoptosis rates of blood lymphocytes, monocytes and NK cells. Blood was obtained from six healthy non-exposed donors, and also from a woman chronically exposed to arsenic. The results indicated that in vitro exposure of mononuclear cells (MNC) from non-exposed donors to sodium arsenite showed no increase in apoptosis as compared to non-treated cells. In contrast, cells obtained from the exposed-donor showed a significant increase in apoptosis after the treatment with sodium arsenite as compared to non-treated cells. This effect was observed in CD3+ and CD56+ but not in CD14+ cells. In addition, we found a preexisting high basal level of apoptosis in MNC from the exposed-donor. These results indicate that chronic exposure to arsenic increases the sensitivity of immune cells to in vitro sodium arsenite-mediated apoptosis.

In vitro studies have suggested that arsenic can modify the activity of macrophages in the mouse producing an over-regulation of the COX-2 and increased concentrations of PGE2 in endothelial cells. These effects may lead in vivo to enhancement of inflammatory and painful responses. In this study we studied the effect of an acute intoxication with sodium arsenite (1, 5, 10, 36 and 100 nmol/kg s.c.) on the nociceptive response of mice in the formalin test. On the other hand, the effect of arsenic on the antinociceptive response mediated by tramadol was evaluated in mice administered with a single dose of the analgesic agent (10 mg/kg s.c.). Arsenic levels in the liver were measured as a marker of the intoxication degree. Our results indicated that the arsenic acute exposure increases the nociceptive behavior in mice in a dose-dependent manner. Accordingly, the exposure to arsenic partially blocked the analgesic effect of tramadol although no statistical differences were reached. These results support the previous in vitro evidences regarding the alterations in the inflammatory-painful processes produced by the acute exposure to arsenic. Moreover, our results suggest that the intoxication with arsenic might exacerbate the pathological state in inflammatory diseases.

Resumen Introducción. El cáncer de próstata (CaP) es la segunda causa de muerte anual por cáncer en el mundo; la exposición a arsénico inorgánico (iAs) es reconocido como un factor de riesgo (1). Un enfoque para tratar el CaP implica el uso del agonista sintético de TLR3: Ácido Poliinosínico:policitidílico (PIC), que al interaccionar con su receptor promueve una respuesta proinflamatoria por la vía de TRIF, así como la inducción de apoptosis en células cancerosas (2). Este tratamiento se emplea en combinación con un retinoide (3), como lo puede ser el ácido 9-cis retinoico (9cRA) que interactúa con el receptor de ácido retinoico beta (RARβ) y con el receptor x de retinoides (RXR) para translocar al núcleo e inducir la expresión de genes asociados a diferenciación celular (4). Dicha combinación induce ambas respuestas en células madre prostáticas (SC) y potencialmente pueden ser empleadas como terapia antineoplásica concomitante (5). Las células epiteliales y células madre transformadas por iAs (CAsE-PE y As-CSC) muestran una desregulación en la vía antitumoral asociada a TLR3. Por lo tanto, la exposición a la combinación PIC + 9cRA no es capaz de activar dicha vía e inducir diferenciación ni la apoptosis. Objetivo. Evaluar las modificaciones en la vía antitumoral mediada por TLR3 asociada a la combinación de PIC y 9cRA en células epiteliales y célula madre transformadas con iAs (As-CSC y CAsE-PE). 2 Material y métodos. Evaluamos la expresión de TLR3, miRNAs, DNMTs, RARβ y de marcadores de diferenciación celular en As-CSC y en CAsE-PE. Esto mediante técnicas de Western blot, PCR en tiempo real para mARN y microARN. Resultados y discusión. Tanto As-CSC como CAsE-PE mostraron una menor expresión basal de TLR3 y RARβ, pero mayor expresión de marcadores de células madre cancerosas (CD44, CD133 y SOX2) en comparación con las líneas celulares de control no malignas WPE-Stem y RWPE, respectivamente. Como era de esperar, la exposición a PIC+9cRA, no mostró activación de la expresión de los intermediarios de la vía antitumoral, pese a ello CAsE-PE mostró una disminución significativa en la expresión relativa de CD44, CD133 y SOX2. Conclusión. Estos resultados sugieren fuertemente que iAs pueden alterar la vía antitumoral TLR3 en las madre prostáticas y parcialmente en las células epiteliales prostáticas. Por lo tanto, los pacientes con CaP expuestos a iAs pueden no responder a esta estrategia terapéutica. Investigadores Personal de apoyo escolar Estudiantes Educadores

"Los nanomateriales de origen tecnológico como lo son las nanopartículas de oro (AuNPs) han sido extensamente estudiados para su aplicación en la nanomedicina, sin embargo hay muy pocos ejemplos de productos nanotecnológicos basados en oro que sean implementados en ensayos clínicos y, hasta el momento, ninguno ha sido aprobado por la Administración de Medicamentos y Alimentos de la Unión Americana (FDA por sus siglas en inglés). Para ser aplicados en el área médica, ya sea como tratamiento o en la línea diagnóstica, todos los sistemas nanoestructurados deben de ser adecuadamente caracterizados en cuanto a sus propiedades fisicoquímicas utilizando el entorno biológico en el que se propone sea empleado, para determinar su potencial de funcionalidad, toxicidad y efectividad El objetivo del presente trabajo fue sintetizar y caracterizar fisicoquímicamente tres sistemas basados en nanopartículas de oro con un tamaño inferiror a 100 nm y de distintas morfologías: esféricas (AuNSP), en forma de barra (AuNRD) y en forma de estrella o multiramificadas (AuNST), evaluando y seleccionando aquellos con la capacidad de ser funcionalizados con β-ciclodextrina, poli-etilenglicol amino tiolado y ácido fólico para determinar su citotoxicidad empleando un modelo in-vitro con dos tipos celulares de un mismo linaje: células madre normales (NSCs) y células madre cancerosas (CSCs) de la próstata humana. Los tres sistemas de AuNPs fueron sintetizados por métodos químicos. Mediante Microscopía de Barrido y Transmisión por electrones (SEM y TEM respectivamente) se analizó la morfología buscada así como el tamaño de las NPs. El análisis por Espectroscopía de Fotoelectrones Emitidos por Rayos X (XPS) y Espectroscopía de Infrarrojo por Transformada de Fourier (FTIR) permitió determinar que el sistema AuNST fue exitosamente funcionalizado (AuNST@BCD-PEG-AF). Por otro lado, el potencial citotóxico de AuNPs fue evaluado en NSC y CSC a través de los ensayos de Liberación de Lactato Deshidrogenasa (LDH) y la Reducción de Sales de Tetrazolio (MTS) al exponer las células a los sistemas AuNST y AuNST@BCD-PEG-AF durante 24 horas en diferentes concentraciones Los resultados mostraron que ambos tipos celulares no ven comprometida gravemente la integridad de su membrana plasmática además de mostrar una alteración significativa en su metabolismo. Finalmente, las concentraciones de Au reportadas de los medios sobrenadantes indican que el sistema AuNST@BCD-PEG-AF presentó mayor asociación a las CSCs en comparación a las NSCs, lo cual permitió deducir que los sistemas en cuestión tienen afinidad para ser ligados a la membrana plasmática y/o internalizados preferentemente en células cancerosas." "Nanomaterials of technological origin such as gold nanoparticles have been extensively studied for applications in nanomedicine, however, there are only a few examples of gold-based nanotechnology products that are implemented in clinical trials and, so far, none of them has been approved by the USA Food and Drug Administration (FDA). Any nanomaterial intended for its application in the biomedical area should be properly characterized physicochemically in the biological environment in which its use is proposed to determine its functionality, toxicity and effectiveness. The aim of the project was to synthesize and physicochemically characterize three systems based on gold nanoparticles with a size < 100 nm and with different morphologies: spherical-shaped (AuNSP), road-shaped (AuNRD) and star-shaped or multi-branched (AuNST), and to evaluate and select those with the ability to be functionalized with βcyclodextrin, polyethylene glycol amino thiolated and folic acid to determine its cytotoxicity using an in-vitro model with two cell types of the same line: normal (NSC) and cancerous stem cells (CSC) of the human prostate. Such three AuNPs systems were synthesized by chemical methods. Scanning and Transmission Microscopy by Electrons (SEM and TEM respectively) were used to evaluate the desired NPs morphology and the size. Through X-ray Emitted Photoelectron Spectroscopy (XPS) and Fourier Transform Infrared Spectroscopy (FTIR) the system based on AuNST was evaluated for a successful functionalization (AuNST@BCD-PEG-AF). On the other hand, the cytotoxic potential of AuNPs was evaluated in NSCs and CSCs through the Lactate Dehydrogenase Release (LDH) and Tetrazolium Salts Reduction (MTS) essays by exposing the cells to the AuNST and AuNST@BCD-PEG-AF systems during 24 hours at different concentrations. Results showed that both cell types do not compromise their plasmatic membrane integrity, furthermore to present significant alterations in their cellular metabolism. Finally, the Au concentrations reported from the supernatant media indicate that the AuNST@BCD-PEG-AF system have a greater association with the CSCs compared to the NSCs, which allowed us to deduce that the systems in question have affinity to be linked to the plasma membrane and/or internalized preferably in cancerous cells."

"Las nanopartículas magnéticas (NPMs) de origen antropogénico, como los son las nanopartículas de hierro principalmente en fase de magnetita (Fe3O4), son liberadas al medio ambiente como resultado, principalmente, de la abrasión de cilindros de combustión y frenos de disco del vehículo. Estas NPs de Fe3O4 se han encontrado en el tejido cerebral humano, sin embargo a diferencia de la magnetita biogénica cuyo tamaño de NP es menor (8 nm), las NPs de Fe3O4 tienen un diámetro medio de 18 nm. En la literatura, la principal vía señalada para que éstas lleguen al cerebro es directamente a través del nervio olfativo. En el presente trabajo se propone la hipótesis de que las NPs de Fe3O4 pueden translocarse desde la circulación sanguínea por medio de capilares, hasta la barrera hematoencefálica (BHE), donde su presencia en este tejido pudiera estar asociada con enfermedades neurodegenerativas como el Alzheimer, debido a que son fuertes inductores del estrés oxidativo. Se llevó a cabo la síntesis, caracterización y evaluación de la toxicidad de las NPs de Fe3O4 desnudas en un modelo in vitro de BHE, consistente en una monocapa de células endoteliales primarias de la microvasculatura de cerebro de rata (rBMEC). El sistema de NPs cubiertas con sílica (Fe3O4@SiO2) se incluyó para propósitos de comparación. Los resultados de la evaluación de la capacidad de ingreso de las NPs sintetizadas en las rBMECs, mostraron que ambos tipos de NPs, desnudas y cubiertas con SiO2 se internalizan de manera efectiva a través del proceso de endocitosis. Adicionalmente ambas NPMs son capaces de atravesar la monocapa de rBMECs, siendo constatado a través de la determinación por ICP de la concentración de Fe3+ y Fe2+ en el medio de cultivo celular. Finalmente, las NPMs de Fe3O4 presentan mayor toxicidad en comparación con NPMs de Fe3O4@SiO2 en tratamientos a menores concentraciones. Estos resultados sugieren que las NPMs de Fe3O4 producidas de manera antropogénica y liberadas al medio ambiente podrían ingresar al tejido cerebral a través de las células endoteliales que recubren la microvasculatura cerebral a través de transitosis, causando además importante daño en la integridad de la membrana y en la funcionalidad de la BHE."