| Toxoplasmosis is a widespread zoonoses caused by Toxoplasma gondii. It is one of the main causes of reproductive wastage in pig, sheep and goat, including human beings. Fetal infections by Toxoplasma gondii can result in neurological sequelae, congenital malformations, and ocular disorders. Toxoplasma gondii has been identified during the last decade as the major causal agent of female reproductive wastage in sheep and women. Acute infection in pregnant women may cause serious health problems when the organism is transmitted to the fetus (congenital Toxoplasmosis), including mental retardation, seizures, blindness, and death. Toxoplasma gondii existed as tachyzoite during acute stage while as bradyzoite during chronic phase in host cells. There are several reports about the deaths and reproductive wastage due to toxoplasmosis in female, but there is little data about male reproductive ability and reproduction function of male host with Toxoplasma gondii infection. Toxoplasmosis can cause fetal resorption, abortion, stillbirth and neonatal mortality in sheep. To the laboratory animal, mice is high susceptible to Toxoplasma gondii infection, and the infection often leads to an acute lethal disease. The rat appears to be rather similar to humans and sheep. Particularly in terms of resistance to acute infection. With respect to the clincal course and in utero transmission, the rat mimics more closely the human situation. Like humans, rats usually develop a sub-clinical chronic infection. In this paper, male reproduction, embryo development of mouse and rat culturing in medium with Toxoplasma gondii in vivo and vitro was studied; meanwhile, through designed primer of testis cell cycle and apoptosis and T cell function, the influence of Toxoplasma gondii infection on male reproduction of mouse and rat discuss, and explore its regulatory mechanism.一The damages on the reproductive system of male mouse and rat induced by Toxoplasma gondii infection1. Effects on reproduction function of male mouse due to Toxoplasma gondii acute infectionThe tachyzoites of Toxoplasma gondii in dosage of 0.3×103/mL were adminstrated intra-peritoneally into adult male NIH mouse. After 4 days, the tall film and section of testis from NIH mice infected by Toxoplasma gondii were made to observed the pathology changes and the spermatogenic cells infected by of Toxoplasma gondii. While, LDH-X of testis, activity and density of semen and amount of teratospermia, alive embryos of female mouse were detected in the mouse infected by Toxoplasma gondii, in comparison with normal mouse. The results showed that the spermatogenic cells cytoplasm and nucleus Toxoplasma gondii tachyzoite were observed in the testis tall film from the mice suffered acute infection by Toxoplasma gondii, and with pathology changes of spermatogenic retention, spermatogonium plasmogen vacuole degeneration in testis section. There was significant difference between the group of Toxoplasma gondii infection and control group in LDH-X of testis, activity and density of semen and amount of teratospermia, alive embryos of female mouse (P<0.05). It was concluded that Toxoplasma gondii infection could influence the reproduction function of male mouse.2. Study on the reproductive ability of male rats induced by Toxoplasma gondii infectionThe tachyzoites of Toxoplasma gondii in dosage of 2×105/mL were administrated ip into adult male Sprague-Dawley rats. After 9 weeks of infection, sperm sexu hormone level, number, vitality, activity and quantity of spermatozoa, activities of enzymes in testis and the pathology of the testicular tissues were determined.Meanwhile, the male rats infected with Toxoplasma gondii were marched with normal female rats at a ratio of 1:2 for one week, and on the 21th day after pregnancy, the female number of corpus luteum, sex ratio and weight, body length and tail length of fetus were measured. The results showed that the relative gravity of testises and epididymis(g/100g) was decreased on the 9th week in the rats infected with 2×105/mL of Toxoplasma gondii. The number, activity, vitality, serum level of sex hormones were all decreased with definite morphological changes in testis of the infected rats. The number of fetus in the pregnant rated matched with the infected male rats was comparatively fewer, but the average body weight, body length, tail length of the fetuses and the sex proportion showed no significant difference between the infected rats and control group rats. It was concluded that Toxoplasma gondii infection could damage the reproductive system and the reproductive ability of infected male rats.3,The influence of Toxoplasma tachyzoites infection on motility of human spermatozoa in vitroSemen samples obtained from 10 healthy volunteers by masturbation were prepared by the swim-up technique. The samples were then inoculated at 37℃with different concentrations of live Toxoplasma tachyzoites varying among 1×103/mL (Group A), 1×104/mL (Group B), 1×105/mL (Group C), 1×106/mL (Group D), 1×107/mL (Group E) and Group F containing Ham's F-10 as the negative control. Motion parameters were analysed by Computer-aided sperm analyzer(CASA) in 0 hour, 1 hour, 2 hours, 4 hours respectively. Modalities of spermatozoa and possible adherence and/or agglutination were observed under the microscope. The results showed that distinct adhesion of spermatozoa to Toxoplasma tachyzoites and agglutination were noticed. In all the motion parameters, progressive motility was affected most and dependent upon the incubation time and tachyzoites concentration. Progressive motility showed a significant difference between Group E and the control (P<0.01), and with the prolongation of incubation time, other parameters were showing more and more differences. Motile velocity of sperms infected by Toxoplasma for 8 hours was more lower than that of control sperms. Motile patterns of sperms infected by Toxoplasma for 8 and 16 hours were turning circle and zigzag; motile velocity of sperms infected by Toxoplasma for 24 hours was less than 10μm/s, and motile patterns were almost turning circle. It was concluded that Toxoplasma tachyzoites inhibited human sperm motility and decrease sperm viability in vitro. Toxoplasma infection significantly influence motile velocity and patterns of sperms. Its mechanism may be the tachyzoite adhession to humen spermatozoa.二The mechanism of damages on the male reproduction of mouse and rat induced by Toxoplasma gondii infection1,The effects of Toxoplasma gondii infection on the testis cell cycle of male mice The testis cell cycle of male mice infected with Toxoplasma gondii was measured by the flow cytometry. Apoptotic spermatogenic cells of mice infected with Toxoplasma gondii were examined by Wright-Giemsa staining and terminal deoxynucleotidyl transferase (TdT) mediated deoxyuridine triphosphate (dUTP)-biotin nick-end labeling(TUNEL) techniques. The results showed that the different doses of Toxoplasma gondii made the testicle cell cycle change. The cells in G0/G1,S phase decreased with the increased dose of Toxoplasma gondii infection. There were significant differences among the 103/mL,104/mI,106 /mL of Toxoplasma gondii and negative control groups (P<0.05). The accounts of cells in G2/M increased and there were significant differences between experimental groups and the negative control (P<0.05). Apoptosis rate of infective group of Toxoplasma gondii was significantly higher than that of control group. It was concluded that Toxoplasma gondii infection could inhibit DNA synthesis of testicle cells, caused the G2 block and delay the mitosis of testicle cells.It was showed apoptosis of spermatogenic cells may be promoted by infections of Toxoplasma gondii.2,The influence of immune function in the rat infected with Toxoplasma gondii.The tachyzoites of T. gondii in dosage of 2×105/mL were administrated intra-peritoneally into clean adult male Sprague-Daeley rats. The percentage of CD3+,CD4+,CD8+T lymphocytes were examined by means of fiow cytometery,and the peripheral blood serum level of IFN-γ,TNF-α, IL-4 was analysed by ELISA on 3, 7, 14, 21, 28, 35, 42, 60 days after rat infected with Toxoplasma gondii. Experimental results showed that the level of IFN-γand IL-4 increased in experimental rats on day 7 (P<0.05) and maintained, level of TNF-αincreased in experimental rats on day 28 (P<0.05), and that of CD8+ T lymphocytes was significantly lower than mat in control (P<0.05) and recovered on day 28. No considerable change was observed on the level of CD4+ T lymphocytes (P>0.05). It was concluded that T. gondii infection could inhibit immune function of infected male rats.3,The effects on apoptosis of testis spermatogenic cells in rats infected with Toxoplasma.SD rat model of toxoplasmosis was established by ip. injection with 2×105/mL RH liver toxoplasma tachyzoits 2 mL. The infected rats were killed to obtain testis spermatogenic on 9th after infection. The testis spermatogenic cells' apoptosis was detected by flow cytomety (FCM). The results showed apoptotic rate of testis spermatogenic cells in the infection rats was obviously higher than that in control group. It was concluded that there was apoptosis in testis spermatogenic cells of toxoplasma.三The effects of azithromycin on rat infected with Toxoplasma gondii of damages on the male reproduction and its mechanismSD rat model of Toxoplasmosis was established by ip. injection with 2×105/mL RH liver toxoplasma tachyzoits 2 mL. Experimental rats were treated with azithromycin (Azi) at a dose of 200mg/kg for 7 days and killed to obtain testis spermatogenic after 9th. The testis spermatogenic cells' apoptosis was detected by flow cytomety (FCM). Results showed the quality of sperm was studies after treated with Azi, sperm concentration and motility rises, sperm deformity drops. Rat male reproduction experiment shows treated group with Azi have higher reproductive ability than infected group. Apoptotic rate of testis spermatogenic cells in treatment group was more lower than that of the infected group. It was concluded that azithromycin was an candidate drug for the treatment of toxoplasmosis.
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