Relationships between innate immunity in bivalve molluscs and environmental pollution

The immune system of invertebrates, such as molluscs consists of innate mechanisms very effective against antigens commonly present in the environment. However, these defense strategies could be altered by pollutants. This review is focused mainly on the effect of metals, PCB, pesticides, PAHs, and others environmental pollutant on immune response of molluscs.El sistema inmune de los invertebrados, como los moluscos, consiste en mecanismos innatos muy eficaces contra antígenos comúnmente presentes en el medio ambiente. Sin embargo, estas estrategias de defensa podrían ser alteradas por los contaminantes. Esta revisión se centra principalmente en el efecto de los metales, PCB, plaguicidas, HAP y otros contaminantes ambientales en la respuesta inmune de los moluscos

Orbitofrontal cortex inactivation impairs early reversal learning in male rats during a sexually motivated task

Fishes are the phylogenetically oldest vertebrate group, which includes more than one-half of the vertebrates on the planet; additionally, many species have ecological and economic importance. Fish are the first evolved group of organisms with adaptive immune mechanisms; consequently, they are an important link in the evolution of the immune system, thus a potential model for understanding the mechanisms of immunoregulation. Currently, the influence of the neurotransmitter acetylcholine (ACh) on the cells of the immune system is widely studied in mammalian models, which have provided evidence on ACh production by immune cells (the noncholinergic neuronal system); however, these neuroimmunomodulation mechanisms in fish and lower vertebrates are poorly studied. Therefore, the objective of this review paper was to analyze the influence of the cholinergic system on the immune response of teleost fish, which could provide information concerning the possibility of bidirectional communication between the nervous and immune systems in these organisms and provide data for a better understanding of basic issues in neuroimmunology in lower vertebrates, such as bony fishes. Thus, the use of fish as a model in biomedical research may contribute to a better understanding of human diseases and diseases in other animals. " 2013 G. A. Toledo-Ibarra et al.",,,,,,"10.1155/2013/536534",,,"http://hdl.handle.net/20.500.12104/42240","http://www.scopus.com/inward/record.url?eid=2-s2.0-84890045313&partnerID=40&md5=d160a095a8a71ba29094534a82c5be4c",,,,,,,,"Clinical and Developmental Immunology",,,,"2013",,"Scopu

Effects of diazinon and diazoxon on the lymphoproliferation rate of splenocytes from Nile tilapia (Oreochromis niloticus): The immunosuppresive effect could involve an increase in acetylcholine levels

The lymphoproliferation rate of spleen cells from Nile tilapia (Oreochromis niloticus) exposed to the organophosphorus pesticide diazinon, to its metabolite diazoxon and to the neurotransmitter acetylcholine, was evaluated in order to explore the immunotoxic mechanism of action of this widely used insecticide. The lymphoproliferative response of spleen cells to mitogenic stimulus was not affected by either diazinon or diazoxon, indicating that these xenobiotic substances do not have direct immunotoxic properties. Conversely, ex vivo assays showed that spleen from fish exposed to diazinon presented a lower acetylcholinesterase activity and a higher acetylcholine concentration than non-exposed controls. Lymphoproliferation assays also indicated that pre-exposure to acetylcholine depleted the proliferative function of spleen cells. Thus the combined information from in vitro and ex vivo experiments suggest that the immunotoxic properties of diazinon in Nile tilapia are indirect and could involve the cholinergic system of lymphocytes. © 2008 Elsevier Ltd. All rights reserved

Influence of the Cholinergic System on the Immune Response of Teleost Fishes: Potential Model in Biomedical Research

Fishes are the phylogenetically oldest vertebrate group, which includes more than one-half of the vertebrates on the planet; additionally, many species have ecological and economic importance. Fish are the first evolved group of organisms with adaptive immune mechanisms; consequently, they are an important link in the evolution of the immune system, thus a potential model for understanding the mechanisms of immunoregulation. Currently, the influence of the neurotransmitter acetylcholine (ACh) on the cells of the immune system is widely studied in mammalian models, which have provided evidence on ACh production by immune cells (the noncholinergic neuronal system); however, these neuroimmunomodulation mechanisms in fish and lower vertebrates are poorly studied. Therefore, the objective of this review paper was to analyze the influence of the cholinergic system on the immune response of teleost fish, which could provide information concerning the possibility of bidirectional communication between the nervous and immune systems in these organisms and provide data for a better understanding of basic issues in neuroimmunology in lower vertebrates, such as bony fishes. Thus, the use of fish as a model in biomedical research may contribute to a better understanding of human diseases and diseases in other animals.Los peces son el grupo filogenéticamente más antiguo de vertebrados, que incluye más de la mitad de los vertebrados del planeta; Además, muchas especies tienen importancia ecológica y económica. Los peces son el primer grupo evolucionado de organismos con mecanismos inmunes adaptativos; Por lo tanto, son un eslabón importante en la evolución del sistema inmunológico, por lo tanto un modelo potencial para la comprensión de los mecanismos de la inmunorregulación. En la actualidad, la influencia del neurotransmisor acetilcolina (ACh) sobre las células del sistema inmune es ampliamente estudiada en modelos de mamíferos, que han proporcionado evidencia sobre la producción de ACh por las células inmunes (el sistema neuronal no colinérgico); Sin embargo, estos mecanismos de neuroimmunomodulación en peces y vertebrados inferiores están mal estudiados. Por lo tanto, el objetivo de este trabajo de revisión fue analizar la influencia del sistema colinérgico en la respuesta inmune de los peces teleósteos, lo que podría proporcionar información sobre la posibilidad de comunicación bidireccional entre el sistema nervioso y el sistema inmunológico en estos organismos y proporcionar datos para una mejor. La comprensión de los problemas básicos de la neuroinmunología en los vertebrados inferiores, como los peces óseos. Por lo tanto, el uso de peces como modelo en la investigación biomédica puede contribuir a una mejor comprensión de las enfermedades y enfermedades humanas en otros animales

Modulation of Immune Response by Organophosphorus Pesticides: Fishes as a Potential Model in Immunotoxicology

Immune response is modulated by different substances that are present in the environment. Nevertheless, some of these may cause an immunotoxic effect. In this paper, the effect of organophosphorus pesticides (frequent substances spilled in aquatic ecosystems) on the immune system of fishes and in immunotoxicology is reviewed. Furthermore, some cellular and molecular mechanisms that might be involved in immunoregulation mechanisms of organophosphorus pesticides are discussedLa respuesta inmunológica está modulada por diferentes sustancias presentes en el medio ambiente. Sin embargo, algunos de estos pueden causar un efecto inmunotóxico. En este trabajo se revisa el efecto de los pesticidas organofosforados (sustancias frecuentes derramadas en los ecosistemas acuáticos) sobre el sistema inmunitario de los peces y en la inmunotoxicología. Además, se discuten algunos mecanismos celulares y moleculares que pueden estar implicados en los mecanismos de inmunoregulación de los plaguicidas organofosforado

Determinación of aflatoxin and fumonisin levels through ELISA and HPLC, on tilapia feed in Nayarit, México

A survey of fungal contamination and presence of aflatoxins (AFs) and fumonisins (FBs) in 30 feed samples collected from 10 tilapia farms during three seasons in Nayarit State, located in north-western Mexico, was carried out using ELISA as screening and High-Performance Liquid Chromatography (HPLC) as confirmatory method. Mycobiota included Aspergillus flavus and Fusarium spp. AFs were detected in 63.3% of samples using ELISA, but confirmation by HPLC revealed that all samples were under the detection limit. Regarding to FBs, positive samples were detected using both methods, with 19 positive samples (60% of total) by ELISA and 14 positive samples (46.6% of total) by HPLC and levels ranging from 0.148 to 2.587 mg/kg. Correlation was observed between both methods (r = 0.516, p = 0.004) for FBs results. No sample exceeded the European maximum levels for any of the mycotoxins. Water activity of samples ranged from 0.345 to 0.655, suggesting that mycotoxin occurrence is probably related to raw material contamination.Se llevó a cabo un estudio de contaminación por hongos y presencia de aflatoxinas (AF) y fumonisinas (FB) en 30 muestras de pienso de 10 granjas de tilapia durante tres temporadas en el estado de Nayarit, en el noroeste de México, Performance Liquid Chromatography (HPLC) como método de confirmación. Mycobiota incluyó Aspergillus flavus y Fusarium spp. AFs se detectaron en el 63,3% de las muestras utilizando ELISA, pero la confirmación por HPLC reveló que todas las muestras estaban bajo el límite de detección. En cuanto a FBs, se detectaron muestras positivas utilizando ambos métodos, con 19 muestras positivas (60% del total) por ELISA y 14 muestras positivas (46,6% del total) por HPLC y niveles de 0,148 a 2,587 mg / kg. Se observó correlación entre ambos métodos (r = 0,516, p = 0,004) para los resultados de FBs. Ninguna muestra superó los niveles máximos europeos para ninguna de las micotoxinas. La actividad de agua de las muestras varió de 0,345 a 0,655, lo que sugiere que la presencia de micotoxinas probablemente esté relacionada con la contaminación de la materia prima

Micotoxinas en Nayarit, México: Estudios de casos

In Nayarit, preliminary studies report the presence of fumonisin B1, T-2 toxin and zearalenone in corn forage and ochratoxin in green coffee. Recently had been investigated the occurrence of fumonisins in feed for tilapia produced in the state of Nayarit. Those antecedents suggest the importance of research in the field of mycotoxins that contributes to the existing legislation, especially in food and feed for human and animal consumption.En Nayarit, estudios preliminares reportan la presencia de fumonisina B1, toxina T-2 y zearalenona en maíz forrajero y ocratoxina en café verde. Además, recientemente se determinó la presencia de fumonisinas en alimento para tilapia producida en el estado de Nayarit. Estos antecedentes sugieren la importancia de realizar investigación en el campo de las micotoxinas, que contribuya a la legislación existente en alimentos destinados al consumo humano y animal

Evaluación del potencial de membrana mitocondrial en linfocitos de tilapia nilótica (Oreochromis niloticus) expuesta a un plaguicida anti-colienstarásico

Cholinergic components have been characterized in mammalian lymphocytes, which may play an important role in the regulation of the immune response. Organophosphate pesticides, being inhibitors of the enzyme acetylcholinesterase, can exert an immunotoxic effect through the alteration of this cholinergic extra-neuronal lymphocyte system, thus altering the physiology of lymphocytes.En linfocitos de mamíferos se han caracterizado componentes colinérgicos, los cuales podrían tener un papel importante en la regulación de la respuesta inmune. Los plaguicidas organofosforados, al ser inhibidores de la enzima acetilcolinesterasa, pueden ejercer un efecto inmunotóxico a través de la alteración de este sistema colinérgico extra-neuronal linfocitario, alterando así la fisiología de los linfocitos

Immunotoxicity and hepatic function evaluation in Nile tilapia (Oreochromis niloticus) exposed to diazinon

The LC50 of the organophosphorus pesticides (OPs) diazinon to Nile tilapia (Oreochromis niloticus) was determined, thereafter, hepatic activity, phagocytic index, percentages of active cells, relative spleen weight, total IgM concentration and lymphoproliferation rates were compared between diazinon exposed groups (LC50 and 1/2LC50) and non-exposed control group. Experimental data show that diazinon is highly toxic for juvenile Nile tilapia (LC50 = 7.830 ppm) and presents immunotoxic properties which affect both the innate and cellular adaptive immune responses of this fish, as revealed by the fact that splenocyte proliferation and phagocytic indices were significantly decreased after acute exposure to the pesticide. However, the hepatic biochemical parameters and the total circulating IgM concentrations were not affected in this experimental model. � 2007 Elsevier Ltd. All rights reserved

Evaluation of pollution in Camichin estuary (Mexico): Pro-oxidant and antioxidant response in oyster (Crassostrea corteziensis)

The physiological system of molluscs, particularly pro-oxidant and antioxidant mechanisms, could be altered by pollutants and induce disturbance on health status and productive parameters of aquatic organisms, such as oyster. Therefore, the aim of this study was to evaluate the chemical contamination in water (total metals and polycyclic aromatic hydrocarbons) and oxidative stress parameters in oysters (Crassostrea corteziensis) in Camichin estuary, located in Mexican Tropical Pacific. The results obtained showed the presence of arsenic, lead and zinc, as well as naphthalene, pyrene and benzo[a]pyrene in concentrations relatively higher than criteria established by local and international guidelines. Regarding the biomarkers of oxidative stress response (H2O2 and O2• concentration, catalase activity, lipid peroxidation, and hydroperoxide concentration), differences between oyster from estuary and control group were significant. These results indicate that these pollutants could be related with oxidative stress detected in oyster.El sistema fisiológico de moluscos, particularmente los mecanismos prooxidantes y antioxidantes, podrían ser alterados por contaminantes e inducir alteraciones en el estado de salud y parámetros productivos de organismos acuáticos, como la ostra. Por lo tanto, el objetivo de este estudio fue evaluar la contaminación química en agua (metales totales e hidrocarburos aromáticos policíclicos) y parámetros de estrés oxidativo en ostras (Crassostrea corteziensis) en el estuario de Camichin, ubicado en el Pacífico tropical mexicano. Los resultados obtenidos mostraron la presencia de arsénico, plomo y zinc, así como de naftaleno, pireno y benzo [a] pireno en concentraciones relativamente mayores que los criterios establecidos por las guías locales e internacionales. En cuanto a los biomarcadores de la respuesta al estrés oxidativo (concentración de H2O2 y O2 •, actividad de catalasa, peroxidación de lípidos e hidroperóxido), las diferencias entre la ostra del estuario y el grupo control fueron significativas. Estos resultados indican que estos contaminantes podrían estar relacionados con el estrés oxidativo detectado en la ostra