Effects of maternal exposure to arsenic on social behavior and related gene expression in F2 male mice

BACKGROUND@#Arsenic is a developmental neurotoxicant. It means that its neurotoxic effect could occur in offspring by maternal arsenic exposure. Our previous study showed that developmental arsenic exposure impaired social behavior and serotonergic system in C3H adult male mice. These effects might affect the next generation with no direct exposure to arsenic. This study aimed to detect the social behavior and related gene expression changes in F2 male mice born to gestationally arsenite-exposed F1 mice.@*METHODS@#Pregnant C3H/HeN mice (F0) were given free access to tap water (control mice) or tap water containing 85 ppm sodium arsenite from days 8 to 18 of gestation. Arsenite was not given to F1 or F2 mice. The F2 mice were generated by mating among control F1 males and females, and arsenite-F1 males and females at the age of 10 weeks. At 41 weeks and 74 weeks of age respectively, F2 males were used for the assessment of social behavior by a three-chamber social behavior apparatus. Histological features of the prefrontal cortex were studied by ordinary light microscope. Social behavior-related gene expressions were determined in the prefrontal cortex by real time RT-PCR method.@*RESULTS@#The arsenite-F2 male mice showed significantly poor sociability and social novelty preference in both 41-week-old group and 74-week-old group. There was no significant histological difference between the control mice and the arsenite-F2 mice. Regarding gene expression, serotonin receptor 5B (5-HT 5B) mRNA expression was significantly decreased (p < 0.05) in the arsenite-F2 male mice compared to the control F2 male mice in both groups. Brain-derived neurotrophic factor (BDNF) and dopamine receptor D1a (Drd1a) gene expressions were significantly decreased (p < 0.05) only in the arsenite-F2 male mice of the 74-week-old group. Heme oxygenase-1 (HO-1) gene expression was significantly increased (p < 0.001) in the arsenite-F2 male mice of both groups, but plasma 8-hydroxy-2'-deoxyguanosine (8-OHdG) and cyclooxygenase-2 (COX-2) gene expression were not significantly different. Interleukin-1β (IL-1β) mRNA expression was significantly increased only in 41-week-old arsenite-F2 mice.@*CONCLUSIONS@#These findings suggest that maternal arsenic exposure affects social behavior in F2 male mice via serotonergic system in the prefrontal cortex. In this study, COX-2 were not increased although oxidative stress marker (HO-1) was increased significantly in arsnite-F2 male mice.

Effect of green tea extract [Camellia sinensis] on kidney toxicity induced by sodium arsenite: a stereological study

Background and Objective: Sodium Arsenite is an environmental pollutant which can generate free radicals causing tissue damage. This study was done to evaluate the effect of Green Tea [GTE], as a strong antioxidant, on kidney tissue in mice treated with Sodium Arsenite

Methods: In this experimental study 24 adult male NMRI mice were randomly allocated into four groups including: control, GTE [l00mg/kg/day], Sodium Arsenite [5mg/kg/day] and Sodium Arsenite + GTE, for 34 days, orally. Animals were scarified and left kidney was taken out, fixed, sectioned, processed and stained using Heidenhain'azan method. Using stereological technique the total volume of kidney, volume of cortex, medulla, proximal and distal tubule, renal corpuscle, gelomerelus, tuft and capillary, membrane and space of Bowman's capsule and length of proximal and distal tubule were determined. Creatinine, BUN and MDA serum samples were measured

Results: The mean of total volume of cortex, proximal tubule, distal tubule, renal corpuscle and gelomerolus, taft, Bowman's capsule space, size of epithelium and lumen of proximal and distal tubule were significantly reduced in Sodium Arsenite group compared to control [P<0.05]. These parameters were significantly increased in the Sodium Arsenite + GTE group in comparison with Sodium Arsenite group [P<0.05], The creatinine, Blood urea nitrogen [BUN] and MDA were significantly increased in the Sodium Arsenite group in compared to the control group [P<0.05]. These parameters were significantly reduced in the Sodium Arsenite + GTE group in comparison with Sodium Arsenite group [P<0.05]

Conclusion: Green tea has a protective role in Sodium Arsenite induced nephrotoxicity

Melatonin protective role in mouse cauda epipidymal spermatozoa damage induced by sodium arsenite / Rol protector de la melatonina en el daño de espermatozoides de cauda epididimaria en ratón producido por arsenito de sodio

We evaluated the sperm parameters such as cauda epididymis weight, sperm count, sperm morphology and sperm DNA stability of adult CF-1 male mice treated daily (oral exposure) with the toxic sodium arsenite (As, 7.0 mg/kg/body weight); Melatonin (Me, 10.0 mg/kg/bw), Me (10.0 mg/kg/bw) plus As (7.0 mg/kg/bw) and Negative Control (NaCl 0.9 percent) to assess acute (8.3 days), chronic (33.2 days) and recovery of testicular damage (66.4 days). Arsenic decreases the number of sperm from chronic treatment (33.2 days) and this effect continued until 66.4 days of treatment. The toxic effect of As also altered the morphology of spermatozoa in all treatment periods when compared to the negative control group. However, Metalonin induced protective effects in periods of 33.2 and 66.4 days of treatment. Additionally, the stability of DNA was significantly affected by arsenic in all periods, but the chronic treatment (33.2 days) in the AsMe revealed increased stability compared to the group treated with arsenic only. Melatonin partially protects sperm toxicity caused by Arsenic, especially during periods of 33.2 and 66.4 days.

Se evaluaron los parámetros espermáticos como peso de la cola del epidídimo, conteo de espermatozoides, morfología de los espermatozoides y estabilidad del ADN de espermatozoides de ratones machos adultos CF-1 tratados diariamente (exposición oral) con el tóxico arsenito de sodio (As, 7,0 mg/kg/peso corporal), melatonina (Me, 10,0 mg/kg/pc, Me (10,0 mg/kg/pc) más As (7,0 mg/kg/pc) y el Control Negativo (NaCl 0,9 por ciento) en evaluación aguda (8,3 días), crónica (33,2 días) y recuperación del daño testicular (66.4 días). El arsénico reduce el número de espermatozoides en el tratamiento crónico (33,2 días) y este efecto continuó hasta 66,4 días. El efecto tóxico de As también altero la morfología de los espermatozoides en todos los períodos de tratamiento cuando se compara con el grupo control negativo. Sin embargo, metalonina indujo efectos protectores en períodos de 33,2 y 66,4 días de tratamiento. La estabilidad del ADN se vio afectada significativamente por el arsénico en todos los periodos, pero en el tratamiento crónico (33,2 días) con AsMe se observa un aumento de la estabilidad em comparación com el grupo tratado con arsénico. Sin embargo, la melatonina protege parcialmente a los espermatozoides del daño causado por arsénico, especialmente durante los períodos de 33,2 y 66,4 días.

Protective role of melatonin in mouse spermatogenesis induced by sodium arsenite / Rol protector de la melatonina en el daño de la espermatogénesis en ratón producido por arsenito de sodio

Arsenic is a testicular environmental toxic. Melatonin (Me), being a potent antioxidant, may reduce the damage caused by arsenic in male fertility. The effects of daily oral exposure of Sodium Arsenite (As; 7.0 mg/kg/bw); Melatonin (Me, 10.0 mg/kg/bw); Me (10.0 mg/kg/bw) plus As (7.0 mg/kg/bw), and Negative Control (NaCl 0.9 percent) in male CF-1 adult mice were assessed in acute (8.3 days), chronic (33.2 days) and recovery (66,4 days) of testicular damage. We evaluated changes in testicular weight and histopathological, morphometric measurements, expression of COX-2 and Androgen Receptor (AR) antigens and lipid peroxidation levels. Treatment resulted in decreased tubular diameter and AR expression, and increased: interstitial area, luminal diameter, COX-2 expression levels and of lipid peroxidation. Co-administration of As and Me partially decreased germ cell degeneration and AR expression levels, improving testicular histopathological parameters. These results indicate that As causes toxicity and testicular germ cell degeneration by induction of oxidative stress. Me partially protects from this damage in mouse testis, acting as scavenger of oxygen radical species.

El arsénico es un tóxico testicular ambiental. La melatonina (Me), que es un potente antioxidante, puede reducir el daño causado por el arsénico en la fertilidad masculina. Se evaluaron los efectos de la exposición oral diaria de arsenito de sodio (As; 7,0 mg/kg/peso corporal), melatonina (Me, 10,0 mg/kg/p.c.); Me (10,0 mg/kg/p.c.) más As (7,0 mg/kg/pc) y el Control Negativo (NaCl 0,9 por ciento) en ratones adultos CF-1 machos, a los 8,3 días (exposición aguda), 33,2 días (crónica) y 66,4 días (recuperación) del daño testicular. Se evaluaron los cambios en el peso testicular y mediciones morfométricas, histopatológicas, expresión de COX-2, del receptor de andrógeno (AR) y los niveles de peroxidación de lípidos. El tratamiento con As resultó en disminución del diámetro tubular y la expresión de AR, y el aumento de: área intersticial, diámetro luminal, los niveles de expresión de COX-2 y peroxidación lipídica. La co-administración de As y Me disminuyó parcialmente la degeneración de células germinales, el aumento de los niveles de expresión de AR y hubo mejoría de los parámetros histopatológicos testiculares. Estos resultados indican que As es tóxico y causa degeneración de células germinales por inducción de estrés oxidativo. Me protege parcialmente este daño en los testículos de ratones, actuando como eliminador de especies radicalarias del oxígeno.

Study of sodium arsenite induced biochemical changes on certain biomolecules of the freshwater catfish Clarias batrachus

Toxic impact of sublethal concentration (1 mg/L; 5% of 96h LC50 value) of sodium arsenite (NaAsO2) on certain biomolecules (proteins, nucleic acids, lipids, and glycogen) of five tissue components (muscles, liver, brain, skin, and gills) of the freshwater catfish Clarias batrachus was analysed. The important toxic manifestations include marked decrease in the concentration of proteins (21.72-45.42% in muscles; 3.42-53.94% in liver; 15.39-45.42% in brain; 15.40-4.00% in skin and 11.35-64.13% in gills), DNA (0.55-22.95% in muscles; 8.33-14.06% in liver; 5.30-18.40% in brain; 13.57-52.80% in skin; and 12.38-31.01% in gills), RNA (42.68-76.16% in muscles; 10.68-39.75% in liver; 5.66-29.05% in brain; 7.72-27.93% in skin and 21.47-44.38% in gills) and glycogen (24.00-51.72% in muscles; 49.11-72.45% in liver; 11.49-26.03% in brain; 26.13-38.05% in skin and 17.80-37.97% in gills). Excepting liver where the lipid content increases (15.82-24.13%), the fat content also showed depletion in their concentration (10.40-29.83% in muscles; 8.30-34.45% in brain; 8.94-31.47% in skin and 12.75-28.86% in gills), in the rest of the organ systems.

Foi analisado o impacto tóxico da concentração subletal (1 mg/L; 5% do valor de LC50 de 96h) do arsenito de sódio (NaAsO2) sobre certas biomoléculas (proteinas, ácidos nucleicos, lipídios e glicogênio) de cinco tecidos (músculos, fígado, cérebro, pele e brânquias) do bagre Clarias batrachus. As manifestações tóxicas importantes incluiram o decréscimo acentuado na concentração de proteinas (21,72-45,42% nos músculos; 3,42-53,94% no fígado; 15,39-45,42% no cérebro; 15,40-4,00% na pele e 11,35-64,13% nas brânquias), DNA (0,55-22,95% nos músculos; 8,33-14,06% no fígado; 5,30-18,40% no cérebro; 13,57-52,80% na pele e 12,38-31,01% nas brânquias), RNA (42,68-76,16% nos músculos; 10,68-39,75% no fígado; 5,66-29,05% no cérebro; 7,72-27,93% na pele e 21,47-44,38% nas brânquias) e glicogênio (24,00-51,72% nos músculos; 49,11-72,45% no fígado; 11,49-26,03% no cérebro; 26,13-38,05% na pele e 17,80-37,97% nas brânquias). Excetuando o fígado onde o conteúdo de lipídeos aumentou (15,82-24,13%), houve uma depleção na concentração de lipídeos no restante dos sistemas orgânicos (10,40-29,83% nos músculos; 8,30-34,45% no cérebro; 8,94-31,47% na pele e 12,75-28,86% nas brânquias).

Study of sodium arsenite induced biochemical changes on certain biomolecules of the freshwater catfish Clarias batrachus

Toxic impact of sublethal concentration (1 mg/L; 5% of 96h LC50 value) of sodium arsenite (NaAsO2) on certain biomolecules (proteins, nucleic acids, lipids, and glycogen) of five tissue components (muscles, liver, brain, skin, and gills) of the freshwater catfish Clarias batrachus was analysed. The important toxic manifestations include marked decrease in the concentration of proteins (21.72-45.42% in muscles; 3.42-53.94% in liver; 15.39-45.42% in brain; 15.40-4.00% in skin and 11.35-64.13% in gills), DNA (0.55-22.95% in muscles; 8.33-14.06% in liver; 5.30-18.40% in brain; 13.57-52.80% in skin; and 12.38-31.01% in gills), RNA (42.68-76.16% in muscles; 10.68-39.75% in liver; 5.66-29.05% in brain; 7.72-27.93% in skin and 21.47-44.38% in gills) and glycogen (24.00-51.72% in muscles; 49.11-72.45% in liver; 11.49-26.03% in brain; 26.13-38.05% in skin and 17.80-37.97% in gills). Excepting liver where the lipid content increases (15.82-24.13%), the fat content also showed depletion in their concentration (10.40-29.83% in muscles; 8.30-34.45% in brain; 8.94-31.47% in skin and 12.75-28.86% in gills), in the rest of the organ systems.

Foi analisado o impacto tóxico da concentração subletal (1 mg/L; 5% do valor de LC50 de 96h) do arsenito de sódio (NaAsO2) sobre certas biomoléculas (proteinas, ácidos nucleicos, lipídios e glicogênio) de cinco tecidos (músculos, fígado, cérebro, pele e brânquias) do bagre Clarias batrachus. As manifestações tóxicas importantes incluiram o decréscimo acentuado na concentração de proteinas (21,72-45,42% nos músculos; 3,42-53,94% no fígado; 15,39-45,42% no cérebro; 15,40-4,00% na pele e 11,35-64,13% nas brânquias), DNA (0,55-22,95% nos músculos; 8,33-14,06% no fígado; 5,30-18,40% no cérebro; 13,57-52,80% na pele e 12,38-31,01% nas brânquias), RNA (42,68-76,16% nos músculos; 10,68-39,75% no fígado; 5,66-29,05% no cérebro; 7,72-27,93% na pele e 21,47-44,38% nas brânquias) e glicogênio (24,00-51,72% nos músculos; 49,11-72,45% no fígado; 11,49-26,03% no cérebro; 26,13-38,05% na pele e 17,80-37,97% nas brânquias). Excetuando o fígado onde o conteúdo de lipídeos aumentou (15,82-24,13%), houve uma depleção na concentração de lipídeos no restante dos sistemas orgânicos (10,40-29,83% nos músculos; 8,30-34,45% no cérebro; 8,94-31,47% na pele e 12,75-28,86% nas brânquias).

Identification of fish nursery areas in a free tributary of an impoundment region, upper Uruguay River, Brazil

This study aims to determine the importance of different environments of the Ligeiro River (upper Uruguay River, Brazil) in fish reproduction. For this purpose, three environments (sampling sites) were selected: rapids, a pool, and the mouth of the Ligeiro River. Ichthyoplankton, zooplankton, and benthos were sampled six times per month from September, 2006 to March, 2007. Zooplankton and ichthyoplankton samples were collected early in the evening with plankton nets (64 µm and 500 µm, respectively). Benthos samples were also collected early in the evening with a Van Veen dredge. Local abiotic variables (temperature, dissolved oxygen, pH, electrical conductivity, water speed, alkalinity, water hardness, and water transparency) were measured simultaneously with the biotic data sampling and were complemented by regional variables (water flow and precipitation). A total of 43,475 eggs and 2,269 larvae were captured. Of these larvae, 80.1% were in the pre-flexion and larval yolk stages. Digestive tract content showed that the greatest degree of repletion among the larvae in more advanced phases occurred in the pool environment. Water speed was the main characteristic used to differentiate the river's rapids and mouth from the pool. The abundance of zooplankton and benthos was not related to the distribution of densities among the different components of the ichthyoplankton. A greater abundance of eggs and larvae with yolk was found in the rapids and river mouth. Ordination analyses showed a connection between the advanced stage larvae and the pool environment. In conclusion, the rapids and river mouth of the Ligeiro River's are important locations for fish reproduction, particularly in regard to spawning and drifting of the ichthyoplankton's initial stages, whereas the pool represents a nursery place for larval growth.

O presente estudo visa determinar a importância de diferentes ambientes do rio Ligeiro (alto rio Uruguai/Brasil) na reprodução dos peixes. Para isto foram selecionados três ambientes (locais): uma corredeira, um poço e a foz do rio Ligeiro. As coletas de ictioplâncton, zooplâncton e bentos foram realizadas seis vezes por mês, entre os meses de setembro de 2006 a março de 2007. As amostras de zooplâncton e ictioplâncton foram coletadas no início da noite com redes de plâncton com malha 64 µm e 500 µm, respectivamente. A coleta de bentos também aconteceu no início da noite e foi realizada com uma draga de Van Veen. Variáveis abióticas locais (temperatura, oxigênio dissolvido, pH, condutividade elétrica, velocidade da água, alcalinidade, dureza e transparência da água) foram mensuradas simultaneamente as coletas dos dados bióticos e complementadas por variáveis regionais (vazão da água e precipitação). Foi capturado um total de 43.475 ovos e 2.269 larvas; destas, 80,1% se encontravam nos estágios larval vitelino e pré-flexão. O conteúdo do trato digestório das larvas mostrou que o maior grau de repleção das larvas em estágios mais avançados foi encontrado no poço. A velocidade da água foi o principal fator que discriminou a corredeira e foz do poço. A abundância do zooplâncton e dos bentos não tiveram relação com distribuição das densidades dos diferentes componentes do ictioplâncton. Houve diferença na distribuição dos diferentes componentes do ictioplâncton nos ambientes estudados, com maior abundância de ovos e larvas com vitelo na corredeira e na foz do rio. As ordenações mostraram relação das larvas em estágios avançados com o poço. Conclui-se, portanto, que para a reprodução dos peixes, a corredeira e a foz se apresentam como importantes sítios para a desova dos peixes e deriva dos estágios iniciais do ictioplâncton, enquanto que o poço mostrou relevância como sítio de crescimento das larvas de peixes no rio Ligeiro.

Arsenic induced toxicity on testicular tissue of mice.

Effect of arsenic was studied on the testicular tissue of Swiss albino mice. Sodium-meta-arsenite (NaAsO2) was administered to adult mice (25 +/- 30 g) at a dose level of 30 mg/L and 40 mg/L through drinking water for 30, 45 and 60 days. After the treatment, the testicular organ was removed, weighed and processed for histopathological observation. No change in the body weight was recorded in treated groups after arsenic exposure but significant decrease in the relative testicular weight was observed in comparison with the control. The result showed that arsenic-treated mice exhibited dose dependent gradual reductions in seminiferous tubular diameter and various gametogenic cell population i.e. resting spermatocyte, pachytene spermatocyte and step-7-spermatid except spermatogonia. Leydig cell atrophy was significantly increased in dose dependent manner indicating a definite effect of arsenic on the spermatogenesis in mice. These observations were supported by gradual reduction in Leydig cell population in the above treated groups. In conclusion, the above results confirm the toxic effect of arsenic in testis of mice.

Effect of arsenite on certain aspects of protein metabolism in fresh water teleost, Tilapia mossambica (Peters).

The sublethal toxicity of sodium arsenite on protein metabolism was investigated in teleost fish, Tilalpia mossambica at the end of 24, 48, 72 and 96 h of exposure. Total protein content, free amino acid content and activities of the enzymes aspartate amino transferase (AAT) and alanine amino transferase (ALAT) in liver, gill, brain and muscle exhibited significant (P<0.05) alterations throughout the investigation in relation to that of control. It is suggested that the fish is able to respond to the stressful situations by gearing up the metabolic activity as revealed by the elevated protein, amino acid content and the activities of AAT and ALAT.