Relationship between testicular lesion and hormone levels in male rats infected with Trypanosoma evansi.

The aim of this study was to evaluate the relationship between testicular lesions and hormone levels in rats experimentally infected with Trypanosoma evansi. For that, the measurement of reproductive hormones, histopathology and biomarkers of cellular injury were carried out in twenty-four animals, which were divided into two groups with 12 animals each. Group A was the negative control, or uninfected, while group B was composed by animals infected with T. evansi. Both groups were divided again into two other subgroups (n=6), from which serum and testicular fragments were collected on days 5 (A1 and B1) and 15 (A2 and B2) post-infection (PI). The morphological analysis showed increased alterations of head and tail of sperm in infected rats when compared with those of the control group. A significant reduction (P<0.01) in the levels of LH, FSH, testosterone and estradiol, associated with an increase in cortisol, was observed in serum of group B when compared with negative control. Additionally, NOx, lipid peroxidation and protein oxidation were enhanced in testicles, indicating the occurrence of cellular lesion. On histopathology, it was possible to observe testicular degeneration, among other disorders in infected animals. Therefore, based on these results, it is possible to conclude that the experimental infection with T. evansi caused changes in the levels of the main hormones of male rats associated with cellular injury.

Infecciones de transmisión sexual en semen: el hombre como vector de transmisión / Sexual transmission infections in semen: men as vector transmission

En los últimos años el estudio de las infecciones de transmisión sexual ha cobrado gran importancia debido principalmente al incremento de estas en parejas heterosexuales y hombres que tienen sexo con hombres. En mujeres existe mucha información de epidemiología y patogénesis de estas infecciones, sin embargo, en hombres la información es muy escasa debido a que la mayoría no presenta sintomatología. En los últimos años se ha evidenciado un creciente interés en el estudio del semen como vía de transmisión, debido principalmente a la afinidad de algunos patógenos con los espermatozoides. Dentro de los principales microorganismos infectantes en semen se encuentran Chlamydia trachomatis, Neisseria gonorrhoeae, Mollicutes, Virus de la Inmunodeficiencia Humana tipos 1 y 2, Virus Herpes Simplex 1 y 2, Virus Papiloma Humano, Virus de la Hepatitis B y C, Citomegalovirus, Virus Epstein-Barr y Trichomonas vaginalis.

Sexually transmitted infections study has become an important issue in these days, mainly due to the increment of heterosexual and men have sex with men partners of people. In women, there is a lot information about epidemiology and pathogenesis of these infections. However, the information is very limited in men, because most infected men are asymptomatic. In recent years, there has been an increasing interest in study of semen as a transmission way, due to the affinity of some pathogens to sperm. The most prevalent microorganisms infecting semen are: Chlamydia trachomatis, Neisseria gonorrhoeae, Mollicutes, Human Immunodeficiency Virus Types 1 and 2 Herpes Simplex Virus 1 and 2, Human Papillomavirus, Hepatitis B and C virus, Cytomegalovirus, Epstein-Barr and Trichomonas vaginalis.

Ejaculate characteristics of rabbits infected with Trypanosoma congolense and changes caused after treatment with Diminazene aceturate (Diminaveto®) / Características eyaculatorias de conejos infectados con Trypanosoma congolense y cambios causados después del tratamiento con Diminazeno aceturato (Diminaveto®)

The effects of experimental Trypanosoma congolense infection on the ejaculate of rabbits and changes caused after treatment with Diminaveto® were investigated using 24 New Zealand White rabbits (bucks). The bucks were housed singly in standard rabbit cages and fed on specialized ration containing 10 percent Protein supplement, grains, legume, salt and fresh water ad libitum during the study. Data on ejaculate characteristics were collected from all the bucks in the first phase (i.e. before infection) and in the second phase (i.e. during infection, with 4.8x10(5) Trypanosoma congolense, intraperitoneally). Similar data were collected from 12 randomly selected bucks treated with 7.0mg/kg Diminaveto® following reconstitution during the third phase. Data collected were analysed using the Paired T- Test and Analysis of Variance. The infection led to significant (P< 0.05) reduction in spermatozoa motility, concentration and mass activity, with a significant (P< 0.05) increase in percentage of sperm cells with morphological abnormalities. Treatment with Diminaveto® led to improvement in all ejaculate parameters investigated. However, it was observed that the ejaculate did not attain the "before-infection" status following treatment with Diminaveto®. The study showed that infection with Trypanosoma congolense in rabbits caused significant reduction in ejaculate characteristics. Treatment with Diminaveto® however led to improvement in the ejaculate though at a rate slower than that at which the infection caused the reduction.

Fue estudiado en 24 conejos Nuevo zelandeses blancos, machos, los efectos de la infección experimental de Trypanosoma congolense sobre la eyaculación y los cambios producidos después del tratamiento con Diminaveto® . Los machos fueron colocados individualmente en jaulas de conejos estándar. Durante el estudio fueron alimentados con ración especializada, con 10 por ciento de suplemento de proteínas, granos, legumbres, sal y agua fresca ad libitum. Los datos sobre las características de la eyaculación se obtuvieron de todos los machos en la primera fase (es decir, antes de la infección) y en la segunda fase (es decir, durante la infección, con 4,8x10(5) Trypanosoma congolense, por vía intraperitoneal). Datos similares se obtuvieron de 12 machos al seleccionados al azar, tratados con Diminaveto® 7,0mg/kg después de la reconstitución durante la tercera fase. Los datos fueron analizados mediante t de student y análisis de varianza. La infección fue significativa (P <0,05) habiendo reducción de la motilidad de los espermatozoides, la concentración y actividad de masas, con un efecto significativo (P <0,05) aumento en el porcentaje de espermatozoides con anomalías morfológicas. El tratamiento con Diminaveto® condujo a una mejoría en todos los parámetros investigados del eyaculado. Sin embargo, se observó que el eyaculado no alcanzó el "antes de la infección" tras el tratamiento con Diminaveto®. Además, el estudio mostró que la infección con Trypanosoma congolense en conejos causó una reducción significativa en las características del eyaculado. Sin embargo, el tratamiento con Diminaveto ® condujo a una mejoría en la eyaculación aunque a un ritmo más lento que en la infección causada por la reducción.

Tritrichomonas fetus extracellular products decrease progressive motility of bull sperm.

Tritrichomonas fetus causes infertility and abortion in cattle; however, there is scarce information regarding the susceptibility of bovine sperm to this parasite. The objective of this study was to analyze in vitro the interaction between T. fetus and bovine sperm and to evaluate the effect of extracellular products secreted by the parasite on these reproductive cells. Sperm from five fertile bulls (Bos taurus taurus, Holstein-Friesian), selected through a Percoll gradient, adhered to T. fetus after 30min of interaction, resulting in agglutination between the two kinds of cells. Based on reverse transcription-polymerase chain reaction (RT-PCR), T. fetus continuously expressed its gene for cysteine peptidase in the presence or absence of sperm. Computer-assisted semen analysis (CASA) revealed that, after 1h incubation of sperm in T. fetus culture extract, the extracellular products secreted by the parasite decreased sperm progressive motility (P<0.05). Although T. fetus extracellular products did not lead to loss of sperm viability (P<0.05) based on the Annexin-V/propidium iodide assay, the percentage of Annexin-V fluorescein isothiocyanate-positive and propidium iodide-positive cells increased (P<0.05) during incubation of sperm in T. fetus culture extract, consistent with cellular damage. In conclusion, extracellular products secreted by T. fetus were cytotoxic to bovine sperm, as they decreased sperm progressive motility; perhaps this contributes to the pathogenesis of T. fetus-induced infertility.

Semen variables of sheep (Ovis aries) experimentally infected with Toxoplasma gondii.

The influence of Toxoplasma gondii on semen variables and sperm morphology of sheep was evaluated in eight reproductive males distributed into three experimental groups: GI, three sheep inoculated with 2.0x10(5) of P strain oocytes; GII, three sheep infected with 1.0x10(6) of RH strain tachyzoites and; GIII two control sheep. Clinical (rectal temperature, cardiac and respiratory frequencies), parasite and serology exams (IIF) were realized. Sperm variables (volume, motility, vigor and concentration) and semen morphology for each sheep were also evaluated. Thus, semen and blood collections were assessed on post-inoculation days (PIDs)-1,3,5,7,11,14 and weekly thereafter up to PID 70. Clinical alterations were observed (hypothermia and anorexia) in infected sheep from groups GI and GII. Parasitic outbreaks were detected in five sheep. All the infected sheep produced antibodies against T. gondii from PID 5 onwards, reaching a peak of 4096 and 8192 for group GI and GII sheep, respectively. Differences (P<0.05) were observed regarding the ejaculate volume between the inoculated groups (oocytes and tachyzoites) and control. Even though experimental toxoplasmic infection resulted in clinical symptomology in the inoculated sheep, the minimal alterations in sperm pathologies could not be directly attributed to T. gondii.

Trichomonas adhere and phagocytose sperm cells: adhesion seems to be a prominent stage during interaction.

Tritrichomonas foetus and Trichomonas vaginalis are extracellular parasites of the urogenital tract of cattle and humans, respectively. They cause infertility and abortion, but there is no documented information on the susceptibility of bovine sperm cells to this cattle parasite. The aim of this present work was to study the effects provoked by T. foetus and T. vaginalis when in interaction with bovine and human sperm cells. The bovine and human spermatozoa were obtained from uninfected bulls and men, respectively, and were exposed to living trichomonads over different periods of time. Light microscopy, video microscopy, scanning, and transmission electron microscopy first revealed a tropism, then a close proximity followed by a tight adhesion between these two different cells. A decrease in the spermatozoa motility was observed as well intense semen agglutination. The adhesion between trichomonads to the sperm cell occurred either by the flagella or sperm head. Motile parasites were observed during the next 12 h, whereas sperm cells in contact with the parasites rapidly became immotile. The parasites were able to maintain the sperm cells attached to their cell surface, followed by phagocytosis. This process began with a tight membrane-membrane adhesion and the incorporation of the sperm cell within an intracellular vacuole. Afterwards, the sperm cell was gradually digested in lysosomes. Many trichomonads were injured and/or died on making contact with the spermatozoa possibly due to necrosis. Results from this study demonstrated that both T. foetus and T. vaginalis interact with sperm cells provoking damage and death of these reproductive cells. Differences in the behavior of both trichomonads were evident, showing that T. vaginalis was much more virulent than T. foetus. The possible role of trichomonads in reproductive failure is discussed.

The male reproductive organs in experimental Chagas' disease. I. Morphometric study of the vas deferens in the acute phase of the disease.

Amastigote forms of Trypanosoma cruzi (Bolivia strain) were detected in the sex organs of male mice 15 days after inoculation. The presence of the parasite close to the lumen of the seminiferous tubules and mixed with spermatozoa in the lumen of the epididymal duct suggests the possibility of transmission of Chagas' disease through coitus. Morphological analysis of the vas deferens revealed structural alterations compatible with the early form of chagasic esophagopathy.