Crotalus durissus sp. rattlesnake venom induces toxic injury in mouse sperm.

Accidents involving snakebites constitute a serious public health problem in many regions around the world. However, there are no study about a possible action of snake venom on the reproductive system. Herein we show that Crotalus durissus sp. (Linnaeus) rattlesnake venom (25 µg/kg of body weight) affected chromatin condensation, and increased the number of sperm with abnormal morphology and the sperm count. In conclusion, besides the known hazards of the C. durissus sp. venom to animal health, this study was the first to show its effect also on male germ cells.

Interacciones epitelio-mesenquimáticas en el desarrollo testicular / Epithelial-mesenchymal transitions in the development of testis

RESUMEN: La espermatogénesis es un proceso continuo que se inicia durante el desarrollo embriofetal. Las relaciones auto, para y yuxtacrinas indican la interdependencia de las células intersticiales (de Leydig) con las células peritubulares (lamina propia) y células sustentaculares (de Sertoli). Ciertos morfógenos son fundamentales en este proceso. Las células sustentaculares son capaces de regular la diferenciación y función de las células peritubulares e intersticiales a través de la producción de IGF1, TGFA, TGFB y DHH. Las células peritubulares son capaces de producir P-Mod-S, regulando la diferenciación de las células sustentaculares, y a través de FGF2 y FGF9 modulan las transiciones epitelio-mesenquimática entre células sustentaculares y mesonefros. También remodelan la membrana basal del condón testicular y regulan la diferenciación y función de las células intersticiales por medio de IGF1, TGFA y TGFB. Las células intersticiales son las reponsables de la producción de testosterona e INSL3, influyendo en la diferenciación sexual masculina. Se plantea que provienen de células mesenquimales del epitelio celómico y mesonefros. Sin embargo, otros autores proponen su origen a partir de células de la cresta neural. Estas influyen a través de mecanismos paracrinos en la proliferación de las células sutentaculares por medio de activina A, teniendo como resultado la expansión del cordón testicular. Las interacciones entre las distintas poblaciones celulares a través de morfógenos inducen una transición epitelio-mesénquima fundamental en la formación y diferenciación de la gónada masculina.

SUMMARY: Spermatogenesis is a continuous process which starts during the embryo-fetal development. Auto, para and juxtacrine relations indicate the interdependence of the interstitial cells (Leydig) with the peritubular cells (lamina propria) and sustentacular cells (Sertoli). Certain morphogens are fundamental in this process. Sustentacular cells are able to regulate differentiation and function and peritubular interstitial cells through production of IGF1, TGFA, TGFB and DHH. Peritubular cells are able to produce P-Mod-S regulating differentiation sustentacular cells and through FGF2 and FGF9 modulate epithelial-mesenchymal transitions between sustentacular cells and mesonephros. They also remodel the basal membrane of the testicular condom and regulate the differentiation and function of the interstitial cells by means of IGF1, TGFA and TGFB. Interstitial cells are responsible for the production of testosterone and INSL3, influencing male sexual differentiation. It is suggested that they come from mesenchymal cells of the coelomic epithelium and mesonephros. However, other authors propose their origin from cells of the neural crest. These influence through paracrine mechanisms proliferation sutentaculares cells by activin A, resulting in the expansion of cord testicular. The interactions between the different cell populations through morphogens induce a fundamental epithelial-mesenchymal transition in the formation and differentiation of the male gonad.

Organophosphorous pesticides: their effects on biosentinel species and humans: control and application in Chile / Pesticidas organofosforados: sus efectos en especies biosentinelas y humanos: control y aplicación en Chile

The environment is negatively affected by the increasing accumulation of both natural and man-made waste and by-products. Organophosphorous pesticides -malathion, diazinon and methamidophos- are used worldwide in pest control. The aim of this report is to review the effects of organophosphates on the male reproductive tract of mice, rats and earthworms, and to evaluate their projection into the human population. Assessing failures in the male reproductive system is an excellent in vivo biomarker to determine the level of toxicity of suspected pollutants. In rodents organophosphates cause decreased testicular weight and sperm density, abnormal tubular plugging and increased teratozoospermia. In earthworms they cause a significant decrease in body weight and alter the spermatheca, with an initial significant increase in immature sperm followed by a significant decrease in sperm count with high frequency of metachromasia. Given the environmental impact of these pesticides -and their potential effects on human health-, international and regional organizations are warning about the correct handling and managing of these substances during work-related and domestic exposures and about their relation to water sources and food, placing a greater emphasis on the school children population due to its higher vulnerability, reduced detoxification capacity, and their endocrine and physiological effects.

El medio ambiente se ve afectado negativamente por la creciente acumulación de desechos y subproductos naturales y artificiales. Los plaguicidas organofosforados malatión, diazinón y metamidofos, son usados en todo el mundo en el control de plagas. El objetivo de este trabajo fue revisar los efectos de los organofosforados en el tracto reproductivo masculino de ratones, ratas y lombrices de tierra, y evaluar su proyección en la población humana. La evaluación de fallas en el sistema reproductor masculino es un excelente biomarcador in vivo para determinar el nivel de toxicidad de los contaminantes químicos. En roedores, los organofosforados causan disminución del peso testicular y de la densidad espermática, obstrucción tubular anormal y aumento de la teratozoospermia. En lombrices de tierra causan una disminución significativa en el peso corporal y alteran la espermateca, con un aumento inicial significativo en espermatozoides inmaduros, seguido de una disminución significativa en el recuento de espermatozoides con alta frecuencia de metacromasia. Dado el impacto medioambiental de estos plaguicidas y sus efectos potenciales en la salud humana, las organizaciones internacionales y regionales advierten sobre el manejo y uso correctos de estas sustancias durante exposiciones laborales y domésticas y sobre su relación con la contaminación de las fuentes de agua y alimentos, colocando énfasis en la población de niños en edad escolar, debido a su mayor vulnerabilidad, reducción de la capacidad de desintoxicación y sus efectos a nivel endocrino y fisiológico.

Disperse Red 1 (textile dye) induces cytotoxic and genotoxic effects in mouse germ cells.

Disperse Red 1 (DR1), which is widely used in the textile industry, is an azo dye that contributes to the toxicity and pollution of wastewater. To assess the toxic effects of DR1 on reproduction, sexually mature male mice (Mus musculus, strain CF-1) were orally (gavage) treated with single doses of the compound at 20, 100 and 500 mg/kg body weight. Testicular features and sperm parameters were evaluated 8.3, 16.6 and 24.9 days after treatments. In addition to testicular toxicity caused by the dye, the data clearly showed an increased frequency of sperm with abnormal morphology and decreased fertility. An increased amount of DNA damage was also detected in testis cells 16.6 and 24.9 days after treatments with 100 and 500 mg/kg. This study demonstrated the toxic and genotoxic effects of DR1, indicating the harmful activity of this dye on reproductive health.

Protective effects of polyunsatutared fatty acids supplementation against testicular damage induced by intermittent hypobaric hypoxia in rats.

BACKGROUND: Intermittent hypobaric hypoxia (IHH) induces changes in the redox status and structure in rat testis. These effects may be present in people at high altitudes, such as athletes and miners. Polyunsaturated fatty acids (PUFA) can be effective in counteracting these oxidative modifications due to their antioxidants properties. The aim of the work was to test whether PUFA supplementation attenuates oxidative damage in testis by reinforcing the antioxidant defense system. The animals were divided into four groups (7 rats per group): normobaric normoxia (~750 tor; pO2 156 mmHg; Nx); Nx + PUFA, supplemented with PUFA (DHA: EPA = 3:1; 0.3 g kg(-1) of body weight per day); hypoxic hypoxia (~428 tor; pO2 90 mmHg; Hx) and, Hx + PUFA. The hypoxic groups were exposed in 4 cycles to 96 h of HH followed by 96 h of normobaric normoxia for 32 days. Total antioxidant capacity (FRAP) and lipid peroxidation (malondialdehyde, MDA) in plasma and reduced (GSH)/oxidized glutathione (GSSG) ratio, tissue lipid peroxidation (TBARS) and antioxidant enzymes activity were assessed at the end of the study in testis. Also, SIRTUIN 1 and HIF-1 protein expression in testis were determined. RESULTS: IHH increased lipid peroxidation in plasma and HIF-1 protein levels in testis. In addition, IHH reduced FRAP levels in plasma, antioxidant enzymes activities and SIRTUIN 1 protein levels in testis. PUFA supplementation attenuated these effects, inducing the increases in FRAP, in the antioxidant enzymes activity and HIF-1 levels. CONCLUSIONS: These results suggest that the IHH model induces a prooxidant status in plasma and testis. The molecular protective effect of PUFA may involve the induction of an antioxidant mechanism.

Efecto de la maca peruana (lepidium meyenii) y de la melatonina sobre el desarrollo testicular del ratón expuesto a hipoxia hipobárica continua / Effect of peruvian maca (lepidium meyenii) and melatonin on testicular development of mice exposed to continuous hypobaric hypoxia

El estudio de la hipoxia hipobárica (HH) determina un problema de salud pública y laboral en poblaciones que habitan en zonas de altura. La disminución del oxígeno afecta a diferentes órganos, incluyendo el testículo. El organismo responde frente a la hipoxia estimulando la angiogénesis, el flujo sanguíneo testicular e incrementa la temperatura intraescrotal, lo cual produce un daño de la espermatogénesis. Nuestro estudio valoró el efecto que produce la HH sobre el testículo del ratón. Se utilizó una cámara hipobárica regulada a 4.200 metros sobre el nivel del mar (msnm), en periodos de hipoxia durante 8,3; 16,6 y 24,9 días, en comparación a un grupo control en normoxia (500 msnm). En estos tres grupos, a unos ratones se administró melatonina, a otros maca (Lepidium meyenii) y a otros la combinación de melatonina y maca. Los objetivos fueron evaluar si la ingesta de maca protege al testículo, reduciendo el daño generado por la hipoxia, y determinar un posible efecto sinérgico de la melatonina y de la maca. La exposición a HH continua produjo una disminución del diámetro de los túbulos seminíferos y del lumen tubular; además, el seminograma demostró una reducción del recuento espermático, un aumento de la teratozoospermia y una reducción de la calidad del ADN espermático. La administración de maca aislada o la combinación de maca y melatonina en animales sometidos a HH produjo una notable mejoría de los parámetros relacionados con la función de los espermatozoides, siendo significativos la disminución del número de espermatozoides con morfología anormal y de la compactación del DNA, alcanzando en algunos casos valores próximos a los de los animales normóxicos. Los datos del presente modelo de HH corroboran los excelentes beneficios que la ingesta de maca tiene sobre la capacidad reproductiva de poblaciones que viven en áreas geográficas de grandes alturas.

Hypobaric hypoxia (HH) is a decisive factor in human health in populations that reside at high altitude levels. Low oxygen rate affects most tissues and organs, including the testis. In humans, hypoxia stimulates angiogenesis, testicular blood flow and increases intrascrotal temperature which determines negative effects on sperm production. Our study researched the effects of HH in mice testicle. Mice were housed in a hypobaric chamber with a setting at 4,200 m above sea level during three different periods of hypoxia (8.3, 16.6 and 24.9 days). Control groups were housed at normoxic conditions (500 m above sea level). Hypoxic mice were treated with melatonin, maca plant (Lepidium meyenii) and melatonin and maca combination. The aim of present study was to determine if maca consumption protects testis against harmful effects of hypoxia and to determine a possible synergistic effect between melatonin and maca administration. In this article we have demonstrated that hypoxia produces a considerable decrease of seminiferous tubules diameter and lumen diameter. Moreover, seminogram showed a reduced sperm count, increased teratozoospermia and a reduction of DNA quality. The HH mice treatment with maca or maca-melatonin combination showed statistically significant improvement at sperm function parameters, and in the reduction of sperm morphology abnormalities and DNA compaction, in some cases attaining rates closer to those registered in normoxic mice. Our experimental data corroborates that maca consumption improves reproductive capacity of populations that inhabit high altitude regions.

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.

Effect of methamidophos on the morphology and male reproductive parameters of the earthworm eisenia foetida / Efecto del metamidofos sobre la morfología y parámetros reproductivos espermáticos de la lombriz de tierra eisenia foetida

The earthworm Eisenia foetida (Annelida, Oligochaeta) is an excellent biosentinel model organism for assessing potential toxicological risks by xenobiotics in terrestrial ecosystems. Methamidophos is an organophosphorous insecticide widely used to control agricultural pests. Its main action is due to inhibition of the enzyme acetylcholinesterase. The aim of this study was to evaluate the toxicity of methamidophos on the morphology and male parameters in Eisenia foetida. After determining the LD50 for methamidophos (85.34 mg/kg soil), five groups were formed, including control subjects, and sprayed with tap water. Methamidophos treated groups were subjected to doses of 1/10, 1/6, 1/3 and 2/3 of the LD50. Each group was analyzed at day 1, 6, 14 and 30 post-treatment. The results show a significant decrease in the weight of all individuals treated with methamidophos, besides showing a coiled body in 100 percent of them. Sperm count showed a significant increase in the treated groups after 1, 6 and 14 days post exposure and a significant decrease by day 30. Using the technique of acridine orange, a significant increase in abnormal metachromatic sperm (red fluorescence) in treated animals was shown. Methamidophos alters the overall behavior in earthworms and the male reproductive parameters of Eisenia foetida possibly altering the structure and conformation of DNA.

La Lombriz de tierra, Eisenia foetida (Annelida, Oligochaeta), constituye un excelente modelo de organismo biocentinela para evaluar los riesgos tóxicos de xenobióticos, en ecosistemas terrestres. Metamidofos es un insecticida organofosforado de amplio uso para controlar plagas agrícolas. Su acción principal se debe a la inhibición de la enzima acetilcolinesterasa. El objetivo de este estudio fue evaluar la toxicidad de metamidofos sobre la morfología y parámetros espermáticos de Eisenia foetida. Una vez determinada la LD50 para metamidofos (85,34 mg/kg de tierra), se tomaron 5 grupos, entre ellos los individuos del grupo control, los cuales fueron asperjados con agua potable. Los grupos tratados con metamidofos fueron sometidos a dosis de 1/10, 1/6, 1/3 y 2/3 de la LD50. Cada grupo fue analizado al día 1, 6, 14, y 30 post tratamiento. Los resultados muestran una baja significativa en el peso de todos los individuos tratados con metamidofos, además de presentar enrrollamiento corporal, en el 100 por ciento de ellos. El recuento espermático presenta un aumento significativo en los grupos tratados a 1,6 y 14 días, para luego decaer significativamente el día 30. El uso de la técnica del naranja de acridina, mostró un aumento significativo de espermatozoides metacromáticos anormales en los animales tratados (fluorescencia de color rojo). Se concluye que Metamidofos altera el comportamiento general de la lombriz de tierra y los parámetros reproductivos espermáticos de Eisenia foetida posiblemente alterando la conformación y estructura del ADN.

Reproducción Estacional en el Macho / Seasonal Reproduction in the Male

Hay una sorprendente relación entre el ambiente y adaptaciones de la conducta reproductiva, muy evidente en los reproductores estacionales que pueden reproducirse en días cortos o largos, de acuerdo a factores proximales, especialmente el fotoperiodo luminoso que provoca cambios fotoneuroendocrinos. Estos, involucran fotoreceptores, un reloj biológico y el aparato neuroendocrino. Las gonadotrofinas (GT), el desarrollo gonadal, la retroalimentación negativa de las GT por los esteroides sexuales, la intervención de las fibras retino-hipotalámico y los núcleos supraquiasmáticos así como la secreción de melatonina, intervienen en esta regulación. El pulso generador del hipotálamo (eminencia media) es importante en el control de la adenohipófisis respecto de la secreción de LH y FSH. En el testículo, las endocrinocitos intersticiales (de Leydig) (que secretan testosterona y también estrógenos), establecen un asa de retroalimentación con la adenohipófisis y el hipotálamo en un circuito de asa larga, corta y ultracorta, donde neuronas neuroendocrinas tienen un rol importante. Los sustentocitos (células de Sertoli) (intratubulares) son importantes por su rol mecánico, trófico y metabólico respecto a las células germinales y la secreción de activina e inhibina, que provoca o inhibe la secreción de FSH respectivamente. Los sustentocitos también secretan muchas proteínas específicas entre las cuales se encuentra la proteína que liga andrógenos (ABP), importante porque concentra 100 veces la testosterona en el parénquima testicular. La secreción tónica, por pulsos de GT, especialmente LH, es debida a actividad hipotalámica a través del control de generación de estos pulsos que se inicia en la pubertad. La reproducción en el potro y el toro se presentan como ejemplos.

There is a surprising interrelationship between environments and adaptation of reproductive behaviour, very evident in seasonal breeders; which may reproduce in long or short days, according to proximal factors, mainly the light photoperiod which triggers photoneuroendocrine changes. These involve photoreceptors, a clock and the neuroendocrine apparatus. Gonadotropins (GT), gonadal development, negative feed back of GT done by sexual steroid, the intervention of the retino-hypothalamic fibers, and suprachiasmatics nucleus as well as melatonine secretion, intervene in this regulation. Of importance is the pulse generator of the hypothalamus (medial eminence) and its control of adenohypofisis for the secretion of LH and FSH. In the testis interstitial endocrine cells (Leydig)(secreting testosterone and also estrogens), establish a feed back loop with the adenohypofisis and hypothalamus in a circuit of long, short and ultra short circuit with neuroendocrine neurons playing a key role. Sustentocyte intratubular (Sertoli)are also important for their trophic, mechanic and metabolic relationships with the germ cells, and the secretions of activine and inhibine, which triggers or inhibits FSH secretions respectively. Sustentocyte also secrete many specifics proteins among which ABP (Androgen Binding Protein) is important because it concentrates 100 fold testosterone in the testicular parenchyme. Tonic secretion by pulses of GT, mainly LH, is due to hypothalamic activity with the control generation of these pulses by puberty. Reproduction in the stallion and the bull are presented as examples.

Boron as testicular toxicant in mice (Mus domesticus) / El boro como tóxico testicular en ratón (Mus domesticus)

It has been reported that boron causes changes in various systems, including the male reproductive system. Residents in some towns in northern Chile were consuming a few years ago in the drinking water 20 times more than the amount established as permissible limit by WHO. This study evaluates the effects in an animal model of high intake of boron on the testis. Boron was administered in the drinking water. Twenty male mice (Mus domesticus), sexually mature, were used, divided into 2 groups: the experimental group was given Boron at a dose of 12 mg/L, and the control group 0.6 mg/L, for 42 days. Sections of testis were obtained for: HE staining (Morphometry and Histopathology), Immunohistochemistry (Cox-2), Mallory and Picrosirious stain (evaluation of tunica albuginea). The results indicate that ingestion of a dose of 12 mg Boron/L produces vacuolization, tubular epithelial desquamation and tamponade. Morphometry revealed decreased tubular diameter and epithelial height and lumen diameter and increased interstitial area in the exposed group. Immunodetection of COX-2 was positive in high percentage of tubules in the intoxicated group. The tunica albuginea was thinner, with decreased percentage of type I collagen fibers and an increase in the percentage of type III collagen fibers in animals exposed to boron in contrast to the control group. Exposure to critical levels of boron produces severe histopathological changes in the testis, altering morphometric parameters and causing overexpression of Cox-2. Finally, evaluation of collagen fibers suggests that Boron produced a degradation of the collagen of the tunica albuginea, causing a decrease in the thickness of it and altering the percentage ratio collagen I/collagen III, a process called collagenolysis...

Se ha reportado que el Boro provoca alteraciones en diversos sistemas, incluido el sistema reproductor masculino. Los habitantes de algunas localidades del norte de Chile estuvieron hasta hace algunos años consumiendo en el agua de bebida 20 veces más que la cantidad establecida como límite permisible por la OMS. El presente estudio evalúa en modelo animal los efectos del alto consumo de Boro sobre el testículo, administrado en el agua de bebida. Se utilizaron veinte ratones (Mus musculus) machos, sexualmente maduros, divididos en 2 grupos; al grupo experimental se administró Boro a una dosis de 12 mg/L, y al grupo control 0.6 mg/L, durante 42 días. Posteriormente se obtuvieron secciones de testículo para: Tinción H-E (Morfometría e Histopatología); Inmunohistoquímica (Cox-2); Tinción de Mallory y Picrosirious Red (evaluación de túnica albugínea). Los resultados indican que la ingestión de Boro a dosis de 12 mg/L produce vacuolización, descamación epitelial y taponamiento tubular. La morfometría revela disminución en el diámetro tubular y altura epitelial, así como aumento del diámetro luminal y del área intersticial en el grupo expuesto. La inmunodetección de COX-2 resultó positiva en gran porcentaje de túbulos en el grupo intoxicado. La túnica albugínea, demostró menor grosor, así como una disminución en el porcentaje de fibras colágenas tipo I y un aumento en el porcentaje de fibras colágenas tipo III en los animales expuestos a Boro en contraste con el grupo control. La exposición a niveles críticos de Boro genera alteraciones histopatológicas severas en el testículo, alterando parámetros morfométricos y provocando la sobreexpresión de COX-2. Finalmente, la evaluación de fibras colágenas sugiere que el Boro produjo una degradación del colágeno de la túnica albugínea, provocando una disminución en el espesor de ésta y alterando la relación porcentual Colágeno I/Colágeno III, proceso llamado colagenólisis...

Alteraciones del espermiograma en pacientes asistidos en la Unidad de Biología de la Reproducción de la Universidad de Chile / Alterations in the semen analysis of patients attending the reproductive biology unit at the University of Chile

En Chile, 10 a 15 por ciento de las parejas son consideradas como infértiles y el factor masculino es responsable en un 50 por ciento de los casos. El espermiograma, es un examen fundamental para el diagnóstico inicial de parejas infértiles. Objetivo: Determinar cambios en cuatro parámetros del espermiograma de mayor valor diagnóstico, según edad, estableciendo el parámetro alterado de mayor frecuencia. Métodos: Se realizo un estudio descriptivo retrospectivo de una muestra de 100 pacientes atendidos por problemas de fertilidad entre los años 2004 y 2009, clasificándolos en cuatro grupos etarios. Resultados: Al evaluar la concentración espermática, el 33 por ciento presenta: 5 baja concentración. El 86 por ciento de los pacientes presento astenozoospermia. El 81 por ciento de los pacientes presento anormalidad en la morfología espermática. La viabilidad espermática fue anormal en el 8 por ciento de los pacientes, siendo significativamente más alto en el grupo etario de mayor edad. Conclusiones: Los parámetros estudiados muestran un alto porcentaje de anormalidad en la población en estudio. Al comparar entre grupos, el grupo de mayor edad (sobre los 47 &los) presenta un aumento significativo del- porcentaje de alteraciones en morfología, motilidad y viabilidad respecto a los otros grupos etarios, estableciéndose la edad como un factor negativo en la calidad espermática. La movilidad corresponde al parámetro mas frecuentemente alterado seguido por la morfología espermática a medida que el varón consultante envejece.

In Chile, 10 to 15 percent of the couples are considered as infertile. Since the male factor is responsible of 50 percent of the cases, spermogram is an essential test for initial diagnosis of the infertile couple. Objective: To analyze the frequency of change in four spermogram parameters -according to age- to determine their diagnostic value. Method: A descriptive retrospective study of spermogram data from 100 patients -subdivided in four age groups- analyzed in our Unit for fertility problems between 2004 and 2009 was performed. Results: In sperm count, 33 percenr showed an abnormally low concentration. An 86 percent of the patients has astenozoospermia. 81 percent of the patients showed abnormal sperm morphology. Sperm viability was subnormal in 8 percent of the patients, being significantly higher in the oldest group. Conclusions: The seminal parameters analyzed revealed a high percentage of anomalies in the studied population. The oldest group had significant percentages of anomalies in sperm motility, morphology and viability, thus corroborating that age is a negative factor that affects semen quality. Sperm motility was the most frequently altered parameter followed by sperm morphology in the population under study.

Vertebral column deformity and hypoxia in Salmo salar / Hipoxia relacionada a deformidad de columna vertebral en Salmo salar

Vertebral Column Deformity (VCD) is a common pathology in Chilean salmon farms, lowering the quality and commercialization of the product. Hypoxia has been related to other musculoskeletal deformities, but not to VCD. This work analyzes the morphology of the vertebral column of Salmo salar alevins, cultured under hypoxic conditions (60 percent O2 saturation in the water tanks) for different time periods after hatching (2, 4, 6 and 8 days). They are compared with their normoxic controls (100 percent O2 saturation). Using histological (H/E), and morphometric techniques, it was found that the time of exposure to hypoxia is inversely proportional to the body length, notochordal diameter and thickness of its sheath. The organic response to hypoxia was quantified by immunohistochemistry for HIF-1a as the sensor of hypoxia. Its expression increased significantly (p<0.05) in the experimental groups that exhibit VCD. Although etiology for VCD is probably multifactorial, this study allows for the conclusion that hypoxia by itself, produces VCD.

La deformidad de columna vertebral (DCV) es una patología que se presenta frecuentemente en la salmonicultura chilena, disminuyendo la calidad y comercialización del producto. La hipoxia ha sido relacionada a otras deformidades musculoesqueléticas pero no a DCV. Este trabajo analiza la morfología de la columna vertebral en alevines Salmo salar cultivados en condiciones de hipoxia (60 por ciento de saturación de O2) en diferentes momentos después de la eclosión (2, 4, 6 y 8 días) y son comparados con sus respectivos controles en normóxia (100 por ciento de saturación de O2). Utilizando técnica histológica (H/E) y morfométrica, se determinó que el tiempo de exposición a hipoxia es inversamente proporcional a la longitud corporal, diámetro notocordal y grosor de su vaina. La respuesta orgánica a hipoxia fue cuantificada mediante inmunohistoquímica contra HIF-1a como censor de hipoxia. Su expresión incrementó significativamente (p<0,05) en los grupos experimentales que presentaron DCV. Aunque la etiología de DCV es probablemente multifactorial, este estudio permite concluir que la exposición a hipoxia puede provocar DCV por sí sola.

Effects of hypoxia on epididymal sperm parameters and protective role of ibuprofen and melatonin.

Hypobaric hypoxia is of interest due to an increase of human populations working at high altitude. Testicular damage is related to the physiological response (neoangiogenesis) to increased intrascrotal blood flow as temperature rises. Hypoxia is a stress factor with overproduction of reactive oxygen species (ROS). The effect of hypoxia in mice reproductive parameters is analyzed. Animals were exposed to simulated hypoxia of 4,200 meters above sea level (m.a.s.l.) in a chamber for 33.2 days, both to continuous (HH) or intermittent hypoxia (HI) with an intermittency period of 4 days hypoxia /4 days normoxia (500 m.a.s.l.). The anti-inflammatory drug Ibuprofen was administered to a group of mice to control vasodilation and increased blood flow. Melatonin was administered to another group of mice as a potent ROS scavenger. Animals in both HH and HI exposure were compared to normoxic non-treated controls. There was a hematological response in hypoxia, with an increase in hematocrit and reticulocytosis. There was also increased teratozoospermia. This damage was more pronounced in HH than HI, suggesting that alternating normoxic periods permits compensation for the effects of hypoxia. In both hypoxia systems, the level of lipoperoxidation and the instability of DNA increased. In HH, there was a reduction of teratozoospermia in melatonin-treated mice. Ibuprofen presented a protective effect on the same parameters as melatonin with both HI and HH. The quality of sperm DNA, fragmentation, unpacking and DNA stability diminished. In conclusion, reproductive damage elicited by HH or HI was partially ameliorated by simultaneous treatment with antiflogistic and/or antioxidant agents.

Effects of hypoxia on epididymal sperm parameters and protective role of ibuprofen and melatonin

Hypobaric hypoxia is of interest due to an increase of human populations working at high altitude. Testicular damage is related to the physiological response (neoangiogenesis) to increased intrascrotal blood flow as temperature rises. Hypoxia is a stress factor with overproduction of reactive oxygen species (ROS). The effect of hypoxia in mice reproductive parameters is analyzed. Animals were exposed to simulated hypoxia of 4,200 meters above sea level (m.a.s.l.) in a chamber for 33.2 days, both to continuous (HH) or intermittent hypoxia (HI) with an intermittency period of 4 days hypoxia /4 days normoxia (500 m.a.s.l.). The anti-inflammatory drug Ibuprofen was administered to a group of mice to control vasodilation and increased blood flow. Melatonin was administered to another group of mice as a potent ROS scavenger. Animals in both HH and HI exposure were compared to normoxic non-treated controls. There was a hematological response in hypoxia, with an increase in hematocrit and reticulocytosis. There was also increased teratozoospermia. This damage was more pronounced in HH than HI, suggesting that alternating normoxic periods permits compensation for the effects of hypoxia. In both hypoxia systems, the level of lipoperoxidation and the instability of DNA increased. In HH, there was a reduction of teratozoospermia in melatonin-treated mice. Ibuprofen presented a protective effect on the same parameters as melatonin with both HI and HH. The quality of sperm DNA, fragmentation, unpacking and DNA stability diminished. In conclusion, reproductive damage elicited by HH or HI was partially ameliorated by simultaneous treatment with antiflogistic and/or antioxidant agents.

Recuento espermático, peso corporal y pesos de órganos reproductivos pos hipoxia hipobárica intermitente simuladan en ratón (mus musculus) / Sperm count, body and reproductive organs weight post simulated intermittent hypobaric hypoxia on mouse (mus musculus)

En ratones sometidos a hipoxia hipobárica intermitente (HI) producto de una exposición simulada a la altura, en cámara hipobárica (asemejándose a condiciones laborales de faena minera del norte de Chile), se evaluó recuento espermático total y cambios en el peso corporal y de órganos reproductivos.El grupo experimental se sometió a HI y el control permaneció en normoxia,ambos durante 108 días. No existieron cambios estadísticamente significativos (p > 0,05) en los pesos pos HI, posiblemente por pequeñas compensaciones durante el periodo de normoxia normobárica o los intervalos de hipoxia hipobárica no fueron lo suficientemente prolongados como para generar cambios. No hubo cambios en el recuento espermático testicular, pero sí en cauda epididimaria, donde el grupo control fue estadísticamente superior,debido posiblemente a enlentecimiento del tránsito entre el testículo y la cauda epididimaria o que ésta no está cumpliendo su función de almacenamiento (tránsito acelerado y depleción de la vía seminal). Por tanto, resulta imprescindible profundizar el estudio de la HI y su repercusión en la reproducción, ya que esta situación afectaría a trabajadores de las faenas mineras en Chile.

Total sperm count and changes in body and reproductive organs weight were evaluated in mice subjected to intermittent hypobaric hypoxia (IHH) product of a simulated exposure to high altitudes, in hypobaric chamber (in a similar situation to that of working conditions of mining activities in the north of Chile). The experimental group was exposed to IHH and the control group maintained in conditions of normoxia, both for 108 days. There were no statistically significant changes (p>0,05) in weights post IHH, possibly because of small compensations during the normobaric normoxia period or the alternant exposure to a hypoxic environment was not sufficient for changes to develop. No changes in testicular sperm count were noted but in epididymal cauda, where control group was statistically higher due to a possible slowness of transit between testicle and epididymal cauda or because the spermstorage function of epididymis is not adequate (accelerated transit and seminal vesicle depletion). Therefore, it is essential to study in depth the IHH and its impact on reproduction, because this situation may affect Chilean mining workers.

Rat spermatogenesis damage in intermittent hypobaric hypoxia and the protective role of melatonin. II: testicular parameters / Daño de la espermatogénesis en rata en la hipoxia hipobárica intermitente y rol protector de la melatonina. II: parámetros testiculares

At present it is not clear if male fertility is affected by intermittent hypobaric hypoxia (IHH). This is an important issue since a large human population works over 3000 masl. This study analyzes testicular changes in adult Sprague Dawley rats after five cycles of IHH (7 day exposure to 4200 masl in a hypobaric chamber / 7 day at 500 masl). The animals were separated into groups of 8, one group was exposed to hypoxia (7 days), and the others to IHH for one to five cycles. Controls (500 masl) were examined at the beginning and at the end of the 70 experimental days. A duplicate set of rats treated with melatonin (supposedly protecting from hypoxia) was also examined, as were their controls, injected with 0,03 percent ethanol (melatonin solvent).Immunohistochemical and histometric analysis of testicular tissue were performed. Damage caused by IHH increases with time. Morphometry reveals an increase in tubular and luminal diameters and a reduction in epithelial height. Inmunohistochemistry for HIF-1alpha shows an increase with time, however the opposite happens with HSP-70. Spermatogenic cells submitted to comet assay present an increase of (+) cells. Melatonin counteracts all this damage, possibly due to its high efficiency as a reactive oxygen species scavenger. In conclusion, IHH exposure damages male reproductive function.

Actualmente no se conoce claramente si la fertilidad masculina se afecta por la hipoxia hipobarica intermitente (IHH). Esto es de importancia porque una gran población humana trabaja sobre 3000 metros sobre el nivel del mar (sml). Este trabajo analiza los cambios testiculares en ratas adultas Sprague Dawley luego de cinco ciclos de IHH (7 días a 4.200 sml) en una camara hipobarica/7días a 500 metros: Normoxia). Los animales de dividieron en grupos de 8; un grupo expuesto a hipoxia (7 días ) y los otros a IHH por uno y hasta cinco ciclos. Los controles ( 500 sml) se analizaron al inicio y al final de los 70 días experimentales. Un set duplicado de ratas tratadas con melatonina (considerada protectora de la Hipoxia) se examinó también, así como sus controles, inyectados con etanol 0,03 por ciento (solvente de la melatonina).Se realizó análisis histométrico e inmunohistoquímico del tejido testicular. El daño causado por IHH aumenta con el tiempo. La morfometría reveló un aumento de los diámetros del túbulo y lumen y una reducción de la altura del epitelio. La inmunohistoquímica de HIF-1 alpha muestra aumento del número de túbulos positivos con el tiempo aunque lo opuesto ocurre para HSP-70. El ensayo de cometa muestra un aumento del número de células espermátogénicas (+). La melatonina controla este daño, posiblemente debido a asu alta eficiencia como neutralizador de especies reactivas del oxígeno. En conclusión, la exposición a IHH daña la función reproductiva masculina.

Chronic toxicity bioassay with populations of the crustacean Artemia salina exposed to the organophosphate diazinon.

A chronic toxicity bioassay was conducted with the microcrustacean Artemia salina as the testing organism for the toxic organophosphate diazinon in order to determine if the species is an appropriate indicator of pollution in aquatic environments. Tests of animal exposure to different concentrations of the toxicant were performed for 24, 48 and 72 hours after larvae hatching. Registered mortality data was used to obtain the lethal dose 50 (LD50) of the organophosphate for each exposure time, considering the immobilization of A. salina larvae as the mortality parameter. The lethal concentration (LD50) in the same exposure times was calculated by evaluating morphological changes on the three initial stages of larval development. Both doses were determined by using probit statistical analysis. Results indicate greater dose-response exactitude after 24 hours of exposure to the toxicant. High sensitivity of the organism to the toxicant was determined, thus indicating that A. salina is an appropriate ecotoxicological bioindicator of aquatic environments polluted with pesticides, with the special consideration that this species is a natural resident of saline water bodies, and thus could be used to control pollution in these environments as a result of the unrestrained usage of such toxic substances.

Chronic toxicity bioassay with populations of the crustacean Artemia salina exposed to the organophosphate diazinon

A chronic toxicity bioassay was conducted with the microcrustacean Artemia salina as the testing organism for the toxic organophosphate diazinon in order to determine if the species is an appropriate indicator of pollution in aquatic environments. Tests of animal exposure to different concentrations of the toxicant were performed for 24, 48 and 72 hours after larvae hatching. Registered mortality data was used to obtain the lethal dose 50 (LD50) of the organophosphate for each exposure time, considering the immobilization of A. salina larvae as the mortality parameter. The lethal concentration (LD50) in the same exposure times was calculated by evaluating morphological changes on the three initial stages of larval development. Both doses were determined by using probit statistical analysis. Results indicate greater dose-response exactitude after 24 hours of exposure to the toxicant. High sensitivity of the organism to the toxicant was determined, thus indicating that A. salina is an appropriate ecotoxicological bioindicator of aquatic environments polluted with pesticides, with the special consideration that this species is a natural resident of saline water bodies, and thus could be used to control pollution in these environments as a result of the unrestrained usage of such toxic substances.

Effect of intermittent hypoxia on the reproduction of rats exposed to high altitude in the Chilean Altiplano.

Environmental parameters such as the large day-night temperature differences, high light radiation, and low humidity may have a synergistic effect with low oxygen pressure. To evaluate the effects of the exposure to intermittent chronic hypobaric hypoxia (ICHH) in nature on rat reproduction, a group of rats was alternately moved to a location at 3400 meters over sea level (moml) for 7 days and returned the subsequent week to sea level; this procedure was repeated six times. Hematological and reproductive parameters were measured and analyzed. At the end of the experimental protocol, hematocrit and hemoglobin concentrations were significantly greater in the ICHH group compared to the control group (Nx) (p < 0.05). The diameter of the seminiferous tubule and the height of the spermatogenic epithelium in ICHH rats presented a significant decrease in relation to Nx rats (p < 0.05). Consequently, the number of epididymal spermatozoa in the experimental animals decreased compared to normal rats, with no evidence of recovery after 84 days. The offspring of the different matings between normal and hypoxic animals decreased proportionally to hypoxia exposure. The low oxygen and the changes in testicular temperature homeostasis would provide a novel local mechanism to explain the decrease in sperm cell production and the reduced number of puppies born. The alterations of the reproductive parameters of the hypoxic female, plus testicular injuries and diminished sperm in males, result in a significant decrease in the reproductive activity of the animals.