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Marta C. Romano - One of the best experts on this subject based on the ideXlab platform.
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Effect of mice Taenia crassiceps WFU Cysticerci infection on the ovarian folliculogenesis, enzyme expression, and serum estradiol
Experimental parasitology, 2019Co-Authors: A. Veloz, Liliana Reyes-vázquez, J.m. Patricio-gómez, Marta C. RomanoAbstract:The murine infection with Taenia crassiceps WFU (T. crassiceps WFU) Cysticerci has been widely used as an experimental model to better understand human cysticercosis. Several reports have established that the host hormonal environment determines the susceptibility and severity of many parasite infections. Female mice are more susceptible to infection with T. crassiceps Cysticerci suggesting that a rich estrogen environment facilitates their reproduction. Ovarian androgens and estrogens are synthesized by key enzymes as P450-aromatase and 17α-hydroxilase/17, 20 lyase (P450C17). The aim of this study was to determine the effect of chronic intraperitoneal infection of T. crassiceps WFU Cysticerci on mice ovarian follicular development, ovulation, the expression of ovarian P450-aromatase and P450C17, and serum 17β-estradiol, key enzymes of the ovarian steroidogenic pathway. To perform this study ovaries and serum were obtained at two, four and six months from T. crassiceps WFU Cysticerci infected mice, and compared to those of healthy animals. The ovaries were fixed and processed for histology or lysed in RIPA buffer for Western blot using specific antibodies for P450C17 and P450-aromatase. 17β-estradiol serum concentration was measured by ELISA. The results showed that the infection with T. crassiceps WFU Cysticerci significantly reduced the number of primordial and primary follicles after two months of infection. Through the course of the study, the corpus luteum number began to decrease, whereas atretic follicles increased. The expression of ovarian P450C17 and P450-aromatase as well as serum E2 concentration were significantly increased in the infected group compared to control. These findings show that chronic infection with Taenia crassiceps WFU may alter the reproductive functions of the female mice host.
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Steroid synthesis by Taenia crassiceps WFU Cysticerci is regulated by enzyme inhibitors.
General and comparative endocrinology, 2013Co-Authors: A. Aceves-ramos, Kaethe Willms, R A Valdez, B. Gaona, Marta C. RomanoAbstract:Abstract Cysticerci and tapeworms from Taenia crassiceps WFU, ORF and Taenia solium synthesize sex-steroid hormones in vitro. Corticosteroids increase the 17β-estradiol synthesis by T. crassiceps Cysticerci. T. crassiceps WFU Cysticerci synthesize corticosteroids, mainly 11-deoxycorticosterone (DOC). The aim of this work was to investigate whether classical steroidogenic inhibitors modify the capacity of T. crassiceps WFU Cysticerci to synthesize corticosteroids and sex steroid hormones. For this purpose, T. crassiceps WFU Cysticerci were obtained from the abdominal cavity of mice, pre-cultured for 24 h in DMEM + antibiotics/antimycotics and cultured in the presence of tritiated progesterone (3H-P4), androstendione (3H-A4), or dehydroepiandrosterone (3H-DHEA) plus different doses of the corresponding inhibitors, for different periods. Blanks with the culture media adding the tritiated precursors were simultaneously incubated. At the end of the incubation period, parasites were separated and media extracted with ether. The resulting steroids were separated by thin layer chromatography (TLC). Data were expressed as percent transformation of the tritiated precursors. Results showed that after 2 h of exposure of the Cysticerci to 100 μM formestane, the 3H-17β-estradiol synthesis from tritiated androstenedione was significantly inhibited. The incubation of Cysticerci in the presence of 3H-DHEA and danazol (100 nM) resulted in 3H-androstenediol accumulation and a significant reduction of the 17β-estradiol synthesis. The Cysticerci 3H-DOC synthesis was significantly inhibited when the parasites were cultured in the presence of different ketoconazole dosis. The drug treatments did not affect parasite’s viability. The results of this study showed that corticosteroid and sex steroid synthesis in T. crassiceps WFU Cysticerci can be modified by steroidogenic enzyme inhibitors. As was shown previously by our laboratory and others, parasite survival and development depends on sex steroids, therefore the inhibition of their synthesis is a good starting point exploited in situations where the inhibition of steroidogenesis could help to control the infection for the development of new treatments, or replacement of the usual therapy in resistant parasite infections. We raise the possibility that these drug actions may be beneficially.
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Taenia crassiceps WFU Cysticerci synthesize corticosteroids in vitro: metyrapone regulates the production.
General and comparative endocrinology, 2012Co-Authors: R A Valdez, Kaethe Willms, Y Gómez, L. Hinojosa, Marta C. RomanoAbstract:Abstract Taenia solium and Taenia crassiceps WFU Cysticerci and tapeworms have the ability to synthesize sex steroid hormones and have a functional 3β-hydroxisteroid dehydrogenase. Corticosteroids (CS) like corticosterone and dexamethasone have been shown to stimulate in vitro estrogen production by Taenia crassiceps WFU Cysticerci. The aim of this work was to study the ability of T. crassiceps WFU Cysticerci to synthesize corticosteroids, and the effect of the inhibitor metyrapone on the CS synthesis. For this purpose T. crassiceps WFU Cysticerci were obtained from the abdominal cavity of mice, thoroughly washed and pre-incubated in multiwells for 24 h in DMEM plus antibiotics/antimycotics. The tritiated CS precursor progesterone ( 3 H-P4) was added to the culture media and parasites cultured for different periods. Blanks containing the culture media plus the 3 H-P4 were simultaneously incubated. Blanks and parasite culture media were ether extracted and analyzed by thin layer chromatography (TLC) in two different solvent systems. Corticosterone production was measured in the culture media by RIA. In some experiments metyrapone (0.1–0.5 mM) was added for 24, 48 or 72 h. Results showed that Cysticerci mainly synthesized tritiated 11-deoxy corticosterone (DOC) and small amounts of corticosterone that was also detected by RIA. Small amounts of 3 H-11-deoxy cortisol were also found. Corticosteroid synthesis was time dependent. The addition of metyrapone significantly inhibited tritiated DOC, deoxycortisol and corticosterone synthesis. These results show for the first time that parasites have the capacity to synthesize CS that is modulated by metyrapone. Data suggest that DOC is the main corticosteroid in the parasites.
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The effect of glucocorticoids on sex steroid synthesis in cultured Taenia crassiceps Wake Forest University (WFU) Cysticerci
Journal of helminthology, 2011Co-Authors: L. Hinojosa, Kaethe Willms, R A Valdez, V. Salvador, A.g. Rodríguez, Marta C. RomanoAbstract:We have shown previously that cultured Taenia crassiceps Wake Forest University (WFU) and Taenia solium Cysticerci, as well as the adult worms, synthesize sex steroid hormones from [3H]steroid precursors and that androgens and oestrogens influence the in vitro development of the parasites. Glucocorticoids (GCs) are used to control the inflammation caused by T. solium Cysticerci in the brain. These steroids stimulate oestrogen synthesis in several tissues. Since there is no information on the effect of GC on the endocrine function of Cysticerci, we investigated the effect of natural and synthetic GCs on the synthesis of oestrogens in cultured T. crassiceps WFU Cysticerci. The Cysticerci were obtained from the peritoneal cavity of infected female BALB/c mice; the cysts were washed extensively and pre-cultured in Dulbecco's Modified Eagle's Medium (DMEM) plus antibiotics for 5 days. The parasites were further cultured with different doses of corticosterone, dexamethasone or the vehicle for 5 days. [3H]Dehydroepiandrosterone (3H-DHEA) was added to the media and the Cysticerci were further incubated for 6 or 24 h. Media were then removed and the steroids ether-extracted. Aliquots of the media were seeded on silica gel plates and developed in solvent systems. Parasites incubated in the presence of 3H-DHEA synthesized [3H]androstenediol, [3H]testosterone and [3H]17β-oestradiol ([3H]17β-E2). The addition of 100 nm or higher corticosterone doses to the media increased [3H]17β-E2 synthesis fourfold after 24 h. Dexamethasone also increased [3H]17β-E2 synthesis. The experiments presented here show for the first time that corticosterone and the synthetic GC dexamethasone modulate the synthesis of oestrogens by Cysticerci.
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Differential in vitro effects of insulin on Taenia crassiceps and Taenia solium Cysticerci
Journal of helminthology, 2009Co-Authors: G. Escobedo, Marta C. Romano, J. Morales-montorAbstract:Hormones play a significant role in murine cysticercosis (Taenia crassiceps), and increase the frequency of porcine cysticercosis caused by Taenia solium. In the present study, we report the in vitro effect of insulin on the larval stages of T. crassiceps (ORF strain) and T. solium. In vitro exposure of T. crassiceps Cysticerci to insulin was found to stimulate this parasite's reproduction twofold with respect to control values, while the same treatment had no effect on T. solium Cysticerci. Moreover, normal female mice (BALB/cAnN) infected with T. crassiceps Cysticerci previously exposed to insulin presented larger parasite loads than mice inoculated with vehicle-treated Cysticerci. To determine the possible molecular mechanisms by which insulin affects T. crassiceps, the insulin receptor was amplified by means of reverse transcriptase-polymerase chain reaction (RT-PCR). Interestingly, both T. crassiceps and T. solium expressed the insulin receptor, although insulin had effects only on T. crassiceps. These results demonstrate that insulin has a dichotomistic effect; it acts directly only on T. crassiceps Cysticerci reproduction, possibly through its binding to a specific insulin receptor synthesized by the parasite. Thus, insulin may be recognized by T. crassiceps cysticercus cells as a mitogenic factor, and contribute to parasite proliferation inside the host, as well as to the female mouse susceptibility to T.crassiceps. This phenomenon has not been reported for cysticercosis caused by T. solium, which could, in part, be related to the poor effect of insulin upon the human parasite.
R A Valdez - One of the best experts on this subject based on the ideXlab platform.
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the synthesis of steroids by taenia crassiceps wfu Cysticerci and tapeworms is related to the developmental stages of the parasites
General and Comparative Endocrinology, 2017Co-Authors: J M Patriciogomez, R A Valdez, Alejandro Veloz, L Aguilarvega, R Zurabian, M C RomanoAbstract:Abstract Taeniids tapeworms are hermaphroditic helminths that gradually develop testis and ovaries in their reproductive units. The larval stage of the tapeworms named cysticercus is a vesicle that contains the scolex and proliferates asexually in the abdominal cavity of mice. Once in the host, they evaginate, attach to the gut and develop into an adult organism, the tapeworm. We have previously reported reported that T. crassiceps ORF and solium Cysticerci transform steroid precursors to androgens and estrogens. Taenia crassiceps WFU Cysticerci can also synthesize corticosteroids. The aim of the present work is to investigate the relationship between steroid synthesis ability and the developmental stage of the parasite T. crassiceps WFU. To this purpose, Cysticerci were obtained from the abdominal cavity of female mice, manually separated in invaginated (IC) and evaginated parasites (EC) and preincubated for 24 h in DMEM plus antibiotics/antimycotics. Next step consisted in incubation for different periods in the fresh media added with tritiated androstenedione (3H-A4) or progesterone (3H-P4) and incubated for different periods. Taenia crassiceps WFU tapeworms were recovered from the intestine of golden hamsters that had been orally infected with Cysticerci. The worms were pre-cultured in DMEM plus FBS and antibiotics, and then incubated without FBS for different time periods, in the presence of 3H-A4 or 3H-P4. At the end of the experiments the media from Cysticerci and tapeworms were analyzed by thin layer chromatography. Results showed that testosterone synthesis was significantly higher in the evaginated Cysticerci and increased with time in culture. The invaginated and evaginated Cysticerci also synthesized small quantities of 17s-estradiol (E2) and estrone. The evaginated Cysticerci synthesized twice more 3H-deoxycorticosterone (3H-DOC) than the invaginated parasites, the production increased significantly with time in culture. Taenia crassiceps WFU tapeworms synthesized significant quantities of 3H-testosterone and small amounts of estrone after only 3 h of culture in the presence of 3H-A4. The tapeworms also transformed 3H-P4 to 3H-DOC and increased its synthesis after 24 h in culture. In summary, our data show the pathways that T. crassiceps WFU Cysticerci use to synthesize sexual steroids in both larval developmental stages and reveals the steroidogenic capacity of the tapeworms.
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Steroid synthesis by Taenia crassiceps WFU Cysticerci is regulated by enzyme inhibitors.
General and comparative endocrinology, 2013Co-Authors: A. Aceves-ramos, Kaethe Willms, R A Valdez, B. Gaona, Marta C. RomanoAbstract:Abstract Cysticerci and tapeworms from Taenia crassiceps WFU, ORF and Taenia solium synthesize sex-steroid hormones in vitro. Corticosteroids increase the 17β-estradiol synthesis by T. crassiceps Cysticerci. T. crassiceps WFU Cysticerci synthesize corticosteroids, mainly 11-deoxycorticosterone (DOC). The aim of this work was to investigate whether classical steroidogenic inhibitors modify the capacity of T. crassiceps WFU Cysticerci to synthesize corticosteroids and sex steroid hormones. For this purpose, T. crassiceps WFU Cysticerci were obtained from the abdominal cavity of mice, pre-cultured for 24 h in DMEM + antibiotics/antimycotics and cultured in the presence of tritiated progesterone (3H-P4), androstendione (3H-A4), or dehydroepiandrosterone (3H-DHEA) plus different doses of the corresponding inhibitors, for different periods. Blanks with the culture media adding the tritiated precursors were simultaneously incubated. At the end of the incubation period, parasites were separated and media extracted with ether. The resulting steroids were separated by thin layer chromatography (TLC). Data were expressed as percent transformation of the tritiated precursors. Results showed that after 2 h of exposure of the Cysticerci to 100 μM formestane, the 3H-17β-estradiol synthesis from tritiated androstenedione was significantly inhibited. The incubation of Cysticerci in the presence of 3H-DHEA and danazol (100 nM) resulted in 3H-androstenediol accumulation and a significant reduction of the 17β-estradiol synthesis. The Cysticerci 3H-DOC synthesis was significantly inhibited when the parasites were cultured in the presence of different ketoconazole dosis. The drug treatments did not affect parasite’s viability. The results of this study showed that corticosteroid and sex steroid synthesis in T. crassiceps WFU Cysticerci can be modified by steroidogenic enzyme inhibitors. As was shown previously by our laboratory and others, parasite survival and development depends on sex steroids, therefore the inhibition of their synthesis is a good starting point exploited in situations where the inhibition of steroidogenesis could help to control the infection for the development of new treatments, or replacement of the usual therapy in resistant parasite infections. We raise the possibility that these drug actions may be beneficially.
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Taenia crassiceps WFU Cysticerci synthesize corticosteroids in vitro: metyrapone regulates the production.
General and comparative endocrinology, 2012Co-Authors: R A Valdez, Kaethe Willms, Y Gómez, L. Hinojosa, Marta C. RomanoAbstract:Abstract Taenia solium and Taenia crassiceps WFU Cysticerci and tapeworms have the ability to synthesize sex steroid hormones and have a functional 3β-hydroxisteroid dehydrogenase. Corticosteroids (CS) like corticosterone and dexamethasone have been shown to stimulate in vitro estrogen production by Taenia crassiceps WFU Cysticerci. The aim of this work was to study the ability of T. crassiceps WFU Cysticerci to synthesize corticosteroids, and the effect of the inhibitor metyrapone on the CS synthesis. For this purpose T. crassiceps WFU Cysticerci were obtained from the abdominal cavity of mice, thoroughly washed and pre-incubated in multiwells for 24 h in DMEM plus antibiotics/antimycotics. The tritiated CS precursor progesterone ( 3 H-P4) was added to the culture media and parasites cultured for different periods. Blanks containing the culture media plus the 3 H-P4 were simultaneously incubated. Blanks and parasite culture media were ether extracted and analyzed by thin layer chromatography (TLC) in two different solvent systems. Corticosterone production was measured in the culture media by RIA. In some experiments metyrapone (0.1–0.5 mM) was added for 24, 48 or 72 h. Results showed that Cysticerci mainly synthesized tritiated 11-deoxy corticosterone (DOC) and small amounts of corticosterone that was also detected by RIA. Small amounts of 3 H-11-deoxy cortisol were also found. Corticosteroid synthesis was time dependent. The addition of metyrapone significantly inhibited tritiated DOC, deoxycortisol and corticosterone synthesis. These results show for the first time that parasites have the capacity to synthesize CS that is modulated by metyrapone. Data suggest that DOC is the main corticosteroid in the parasites.
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The effect of glucocorticoids on sex steroid synthesis in cultured Taenia crassiceps Wake Forest University (WFU) Cysticerci
Journal of helminthology, 2011Co-Authors: L. Hinojosa, Kaethe Willms, R A Valdez, V. Salvador, A.g. Rodríguez, Marta C. RomanoAbstract:We have shown previously that cultured Taenia crassiceps Wake Forest University (WFU) and Taenia solium Cysticerci, as well as the adult worms, synthesize sex steroid hormones from [3H]steroid precursors and that androgens and oestrogens influence the in vitro development of the parasites. Glucocorticoids (GCs) are used to control the inflammation caused by T. solium Cysticerci in the brain. These steroids stimulate oestrogen synthesis in several tissues. Since there is no information on the effect of GC on the endocrine function of Cysticerci, we investigated the effect of natural and synthetic GCs on the synthesis of oestrogens in cultured T. crassiceps WFU Cysticerci. The Cysticerci were obtained from the peritoneal cavity of infected female BALB/c mice; the cysts were washed extensively and pre-cultured in Dulbecco's Modified Eagle's Medium (DMEM) plus antibiotics for 5 days. The parasites were further cultured with different doses of corticosterone, dexamethasone or the vehicle for 5 days. [3H]Dehydroepiandrosterone (3H-DHEA) was added to the media and the Cysticerci were further incubated for 6 or 24 h. Media were then removed and the steroids ether-extracted. Aliquots of the media were seeded on silica gel plates and developed in solvent systems. Parasites incubated in the presence of 3H-DHEA synthesized [3H]androstenediol, [3H]testosterone and [3H]17β-oestradiol ([3H]17β-E2). The addition of 100 nm or higher corticosterone doses to the media increased [3H]17β-E2 synthesis fourfold after 24 h. Dexamethasone also increased [3H]17β-E2 synthesis. The experiments presented here show for the first time that corticosterone and the synthetic GC dexamethasone modulate the synthesis of oestrogens by Cysticerci.
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Metabolism of steroid hormones by Taenia solium and Taenia crassiceps Cysticerci.
The Journal of Steroid Biochemistry and Molecular Biology, 2006Co-Authors: Pedro Jimenez, R A Valdez, Marta C. RomanoAbstract:Abstract Previous in vitro experiments showed that both, Taenia crassiceps and Taenia solium Cysticerci have the ability to metabolize exogenous androstenedione to testosterone. Here we evaluate on the capacity of both Cysticerci to synthesize several sex steroid hormones, using different hormonal precursors. Experiments using thin layer chromatography (TLC) showed that both Cysticerci were able to produce 3 H-hydroxyprogesterone, 3 H-androstenedione and 3 H-testosterone when 3 H-progesterone was used as the precursor. They also synthesized 3 H-androstenediol and 3 H-testosterone when 3 H-dehydroepiandrosterone was the precursor. In addition, both Cysticerci interconverted 3 H-estradiol and 3 H-estrone. These results, strongly suggest the presence and activity of the Δ4 and Δ5 steroid pathway enzymes, 3β-hydroxysteroid dehydrogenase/Δ 5-4 isomerase-like enzyme (3β-HSD), that converts androstenediol into testosterone; and the 17β-hydroxysteroid dehydrogenase that interconverts estradiol and estrone, in both types of Cysticerci.
P.c. Fan - One of the best experts on this subject based on the ideXlab platform.
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vaccination trials against taenia solium eggs in pigs injected with frozen oncospheres of t solium or taenia saginata asiatica
Journal of Microbiology Immunology and Infection, 2003Co-Authors: P.c. Fan, Wencheng Chung, Chunyun LinAbstract:In this study, 12 Small-Ear-Miniature pigs aged 142 to 185 days were used to determine whether pigs injected with nonviable oncospheres of Taenia solium or Taenia saginata asiatica can become resistant to the challenge of viable eggs of T. solium. The 12 pigs were equally divided into 4 groups: 3 experimental groups in which each pig was injected subcutaneously with a mixture of 0.2 mL complete Freund's adjuvant and 10(4)/0.2 mL nonviable Taiwan/Asian Taenia, Indonesia Taenia, or T. solium oncospheres, and 1 control group in which each pig was injected subcutaneously with 0.2 mL phosphate buffer solution and 0.2 mL complete Freund's adjuvant. Each pig was orally inoculated with 10000 viable T. solium eggs 1 month later. The infection rates were 100% (2/2), 100% (3/3), 33% (1/3), and 100% (3/3) and Cysticerci recovery rates were 1.3% (254/20000), 1.2% (371/30000), 0.01% (4/30000), and 8.6% (2,577/30000), respectively. Except for the location of 72 Cysticerci located in the viscera, 3134 Cysticerci were recovered from the muscles. In the experimental groups, 4 Cysticerci recovered were viable and the remaining 625 were either calcified or degenerated. However, 2567 Cysticerci recovered from the control group remained viable and only 10 were calcified or degenerated. The results indicate that in addition to the vaccine of T. solium, those of Taiwan Taenia and Indonesia Taenia can also induce high-crossing immunologic reactions against T. solium infection.
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Experimental studies on physiological and morphological aspects of Cysticercus cellulosae in pigs.
Journal of microbiology immunology and infection = Wei mian yu gan ran za zhi, 2001Co-Authors: P.c. FanAbstract:Three Small-Ear-Miniature, 3 Landrace-Small-Ear-Miniature, and one Douc-Yorkshire-Landrace pigs were inoculated orally with 100 000 eggs of Zhengzhou strain or 10 000 eggs of Harbin strain of Taenia solium. A total of 3739 Cysticerci were recovered from 3 Small-Ear-Miniature and 3 Landrace-Small-Ear-Miniature pigs, giving an infection rate of 85.7% and a cysticercus recovery rate of 1.1%. The predilection sites of Cysticercus cellulosae in descending order were leg muscles, abdominal muscles, thoracic muscles, liver, head muscles, diaphragm, tongue, heart, trachea, and omentum/testes. Except 2 calcified Cysticerci in the tongue, 2 in the heart, and 176 in the liver, the remaining Cysticerci were all alive. The greatest number of Cysticerci per 100 g of muscles or viscera was found in the head muscles, followed by the leg, diaphragm, heart, tongue, thoracic, abdominal, omentum, testes, and trachea. All Cysticerci were evaginated in pig's bile after fluid was drawn out from Cysticerci, whereas evagination occurred in only 83.2% of those without fluid drawing. In 364 evaginated Cysticerci, the mean length and width of scolex, proglottid, and bladder, and diameter of rostellum and sucker were 826 x 747 microm, 5,370 x 1,734 microm, 2,885 x 3,002 microm, 155 microm, and 253 microm, respectively. In the protoscolex, the mean number of segments was 33. Each cysticercus had 2 rows of rostellar hooks on the scolex, and the mean length and width of inner and outer hooks were 151 x 18 microm and 117 x 14 microm, respectively. The number of paired hooks ranged from 10 to 18.
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rodent model for long term maintenance and development of the viable Cysticerci of taenia saginata asiatica
Korean Journal of Parasitology, 2000Co-Authors: I C Wang, W. C. Chung, P.c. FanAbstract:Although oncospheres of Taenia saginata asiatica can develop into Cysticerci in immunodeficiency, immunosuppressed, and normal mice, no detailed information on the development features of these Cysticerci from SCID mice is available. In the present study, the tumor-like cyst was found in the subcutaneous tissues of each of 10 SCID mice after 38-244 days inoculation with 39,000 oncospheres of T. s. asiatica. These cysts weighed 2.0-9.6 gm and were 1.5-4.3 cm in diameter. The number of Cysticerci were collected from these cysts ranged from 125 to 1,794 and the cysticercus recovery rate from 0.3% to 4.6%. All Cysticerci were viable with a diameter of 1-6 mm and 9 abnormal ones each with 2 evaginated protoscoleces were also found. The mean length and width of scolex, protoscolex, and bladder were 477 × 558, 756 × 727, and 1,586 × 1,615 µm, respectively. The diameters of suckers and rostellum were 220 µm and 70 µm, respectively. All Cysticerci had two rows of rostellar hooks. These findings suggest that the SCID mouse model can be employed as a tool for long-term maintenance of the biological materials for advanced studies of immunodiagnosis, vaccine development, and evaluation of cestocidal drugs which would be most benefit for the good health of the livestocks.
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Oncospheres of Taenia solium and T. saginata asiatica develop into metacestodes in normal and immunosuppressed mice.
Journal of helminthology, 1999Co-Authors: I C Wang, W. C. Chung, Akira Ito, J.x. Guo, P.c. FanAbstract:Normal and immunosuppressed mice were infected with oncospheres of Taenia saginata asiatica and T. solium. Although normal ICR mice were not susceptible to these two parasites, Cysticerci were recovered from the immunosuppressed ones following venous injection. For T. s. asiatica, immunosuppressed ICR mice had an infection rate of 12.5% and six Cysticerci of this parasite were recovered from three males. After injection of T. solium oncospheres, a high infection rate of 57% was obtained and 23 Cysticerci were collected from 13 male immunosuppressed ICR mice. The immunosuppressed C57 mice had the highest infection rate (100%) and cysticercus recovery rate (2.4%) for T. solium. The infection rate and cysticercus recovery rate in six normal C57 mice were 40% and 3% respectively. The immunosuppressed ICR, Balb/c and C3H mice were also susceptible to T. s. asiatica.
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Survival of Taenia solium Cysticerci in carcasses of pigs kept at 4 C
The Journal of parasitology, 1998Co-Authors: P.c. Fan, Y. X., C. H. Kuo, W. C. ChungAbstract:In the present study, the survival of Cysticerci of Taenia solium in carcasses of 1 Small-Ear-Miniature and 2 Landrace Small-Ear-Miniature pigs kept in a refrigerator at 4 C was determined. The viability of the Cysticerci was determined by observing evagination and active movement of the scolex under a fluorescent light after digestion in pig bile. Although no viable Cysticerci were found after day 30, 58.8% Cysticerci survived between day 26 and day 30. Moreover, more than 80% of the Cysticerci were viable between day 1 and day 25. These findings indicate that taeniasis solium can be transmitted through eating raw or undercooked pork or viscera of pigs following refrigeration at 4 C for less than 30 days.
M C Romano - One of the best experts on this subject based on the ideXlab platform.
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the synthesis of steroids by taenia crassiceps wfu Cysticerci and tapeworms is related to the developmental stages of the parasites
General and Comparative Endocrinology, 2017Co-Authors: J M Patriciogomez, R A Valdez, Alejandro Veloz, L Aguilarvega, R Zurabian, M C RomanoAbstract:Abstract Taeniids tapeworms are hermaphroditic helminths that gradually develop testis and ovaries in their reproductive units. The larval stage of the tapeworms named cysticercus is a vesicle that contains the scolex and proliferates asexually in the abdominal cavity of mice. Once in the host, they evaginate, attach to the gut and develop into an adult organism, the tapeworm. We have previously reported reported that T. crassiceps ORF and solium Cysticerci transform steroid precursors to androgens and estrogens. Taenia crassiceps WFU Cysticerci can also synthesize corticosteroids. The aim of the present work is to investigate the relationship between steroid synthesis ability and the developmental stage of the parasite T. crassiceps WFU. To this purpose, Cysticerci were obtained from the abdominal cavity of female mice, manually separated in invaginated (IC) and evaginated parasites (EC) and preincubated for 24 h in DMEM plus antibiotics/antimycotics. Next step consisted in incubation for different periods in the fresh media added with tritiated androstenedione (3H-A4) or progesterone (3H-P4) and incubated for different periods. Taenia crassiceps WFU tapeworms were recovered from the intestine of golden hamsters that had been orally infected with Cysticerci. The worms were pre-cultured in DMEM plus FBS and antibiotics, and then incubated without FBS for different time periods, in the presence of 3H-A4 or 3H-P4. At the end of the experiments the media from Cysticerci and tapeworms were analyzed by thin layer chromatography. Results showed that testosterone synthesis was significantly higher in the evaginated Cysticerci and increased with time in culture. The invaginated and evaginated Cysticerci also synthesized small quantities of 17s-estradiol (E2) and estrone. The evaginated Cysticerci synthesized twice more 3H-deoxycorticosterone (3H-DOC) than the invaginated parasites, the production increased significantly with time in culture. Taenia crassiceps WFU tapeworms synthesized significant quantities of 3H-testosterone and small amounts of estrone after only 3 h of culture in the presence of 3H-A4. The tapeworms also transformed 3H-P4 to 3H-DOC and increased its synthesis after 24 h in culture. In summary, our data show the pathways that T. crassiceps WFU Cysticerci use to synthesize sexual steroids in both larval developmental stages and reveals the steroidogenic capacity of the tapeworms.
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Metabolism of steroid hormones by Taenia solium and Taenia crassiceps Cysticerci.
The Journal of steroid biochemistry and molecular biology, 2006Co-Authors: Pedro Jimenez, R A Valdez, M C RomanoAbstract:Previous in vitro experiments showed that both, Taenia crassiceps and Taenia solium Cysticerci have the ability to metabolize exogenous androstenedione to testosterone. Here we evaluate on the capacity of both Cysticerci to synthesize several sex steroid hormones, using different hormonal precursors. Experiments using thin layer chromatography (TLC) showed that both Cysticerci were able to produce (3)H-hydroxyprogesterone, (3)H-androstenedione and (3)H-testosterone when (3)H-progesterone was used as the precursor. They also synthesized (3)H-androstenediol and (3)H-testosterone when (3)H-dehydroepiandrosterone was the precursor. In addition, both Cysticerci interconverted (3)H-estradiol and (3)H-estrone. These results, strongly suggest the presence and activity of the Delta4 and Delta5 steroid pathway enzymes, 3beta-hydroxysteroid dehydrogenase/Delta(5-4) isomerase-like enzyme (3beta-HSD), that converts androstenediol into testosterone; and the 17beta-hydroxysteroid dehydrogenase that interconverts estradiol and estrone, in both types of Cysticerci.
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Steroid hormone production by parasites: the case of Taenia crassiceps and Taenia solium Cysticerci.
The Journal of steroid biochemistry and molecular biology, 2003Co-Authors: M C Romano, R A Valdez, A L Cartas, Y Gómez, C LarraldeAbstract:Many examples of reciprocal endocrine interactions between parasites and hosts have been found in insects, arthropods and mammals. Cysticercosis produced by Taenia solium metacestodes is a widely distributed parasite infection that affects the human and the pig. Taenia crassiceps experimental murine cysticercosis has been used to explore the role of biological factors involved in host-parasite interactions. We had shown that T. crassiceps cysticercosis affects the serum concentration of steroid hormones and the reproduction behavior of the male mice host. In an effort to understand the biology of the parasite, we had investigated the parasite capacity to produce sex steroids. For this purpose, T. crassiceps Cysticerci were incubated in the presence of different steroid precursors. TLC and recrystallization procedures showed that testosterone is produced from 3H-androstenedione in Cysticerci. The conversion of 3H-testosterone to androstenedione, although present is much less significant. In addition, we had studied the production of testosterone by T. solium Cysticerci. For this purpose, Cysticerci were dissected from pork meat and incubated as above described. The results showed that T. solium Cysticerci also produce testosterone. We have speculated about the importance of androgens in the growth of T. crassiceps Cysticerci and found that the addition of the antiandrogen flutamide to the culture media of the parasites significantly decreased 3H-thymidine incorporation. We therefore hypothesized, that the ability of Cysticerci to produce testosterone from steroid precursors might be important for the parasite growth and development.
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Steroid synthesis by Taenia crassiceps WFU Cysticerci is regulated by enzyme inhibitors.
General and comparative endocrinology, 2013Co-Authors: A. Aceves-ramos, Kaethe Willms, R A Valdez, B. Gaona, Marta C. RomanoAbstract:Abstract Cysticerci and tapeworms from Taenia crassiceps WFU, ORF and Taenia solium synthesize sex-steroid hormones in vitro. Corticosteroids increase the 17β-estradiol synthesis by T. crassiceps Cysticerci. T. crassiceps WFU Cysticerci synthesize corticosteroids, mainly 11-deoxycorticosterone (DOC). The aim of this work was to investigate whether classical steroidogenic inhibitors modify the capacity of T. crassiceps WFU Cysticerci to synthesize corticosteroids and sex steroid hormones. For this purpose, T. crassiceps WFU Cysticerci were obtained from the abdominal cavity of mice, pre-cultured for 24 h in DMEM + antibiotics/antimycotics and cultured in the presence of tritiated progesterone (3H-P4), androstendione (3H-A4), or dehydroepiandrosterone (3H-DHEA) plus different doses of the corresponding inhibitors, for different periods. Blanks with the culture media adding the tritiated precursors were simultaneously incubated. At the end of the incubation period, parasites were separated and media extracted with ether. The resulting steroids were separated by thin layer chromatography (TLC). Data were expressed as percent transformation of the tritiated precursors. Results showed that after 2 h of exposure of the Cysticerci to 100 μM formestane, the 3H-17β-estradiol synthesis from tritiated androstenedione was significantly inhibited. The incubation of Cysticerci in the presence of 3H-DHEA and danazol (100 nM) resulted in 3H-androstenediol accumulation and a significant reduction of the 17β-estradiol synthesis. The Cysticerci 3H-DOC synthesis was significantly inhibited when the parasites were cultured in the presence of different ketoconazole dosis. The drug treatments did not affect parasite’s viability. The results of this study showed that corticosteroid and sex steroid synthesis in T. crassiceps WFU Cysticerci can be modified by steroidogenic enzyme inhibitors. As was shown previously by our laboratory and others, parasite survival and development depends on sex steroids, therefore the inhibition of their synthesis is a good starting point exploited in situations where the inhibition of steroidogenesis could help to control the infection for the development of new treatments, or replacement of the usual therapy in resistant parasite infections. We raise the possibility that these drug actions may be beneficially.
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Taenia crassiceps WFU Cysticerci synthesize corticosteroids in vitro: metyrapone regulates the production.
General and comparative endocrinology, 2012Co-Authors: R A Valdez, Kaethe Willms, Y Gómez, L. Hinojosa, Marta C. RomanoAbstract:Abstract Taenia solium and Taenia crassiceps WFU Cysticerci and tapeworms have the ability to synthesize sex steroid hormones and have a functional 3β-hydroxisteroid dehydrogenase. Corticosteroids (CS) like corticosterone and dexamethasone have been shown to stimulate in vitro estrogen production by Taenia crassiceps WFU Cysticerci. The aim of this work was to study the ability of T. crassiceps WFU Cysticerci to synthesize corticosteroids, and the effect of the inhibitor metyrapone on the CS synthesis. For this purpose T. crassiceps WFU Cysticerci were obtained from the abdominal cavity of mice, thoroughly washed and pre-incubated in multiwells for 24 h in DMEM plus antibiotics/antimycotics. The tritiated CS precursor progesterone ( 3 H-P4) was added to the culture media and parasites cultured for different periods. Blanks containing the culture media plus the 3 H-P4 were simultaneously incubated. Blanks and parasite culture media were ether extracted and analyzed by thin layer chromatography (TLC) in two different solvent systems. Corticosterone production was measured in the culture media by RIA. In some experiments metyrapone (0.1–0.5 mM) was added for 24, 48 or 72 h. Results showed that Cysticerci mainly synthesized tritiated 11-deoxy corticosterone (DOC) and small amounts of corticosterone that was also detected by RIA. Small amounts of 3 H-11-deoxy cortisol were also found. Corticosteroid synthesis was time dependent. The addition of metyrapone significantly inhibited tritiated DOC, deoxycortisol and corticosterone synthesis. These results show for the first time that parasites have the capacity to synthesize CS that is modulated by metyrapone. Data suggest that DOC is the main corticosteroid in the parasites.
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The effect of glucocorticoids on sex steroid synthesis in cultured Taenia crassiceps Wake Forest University (WFU) Cysticerci
Journal of helminthology, 2011Co-Authors: L. Hinojosa, Kaethe Willms, R A Valdez, V. Salvador, A.g. Rodríguez, Marta C. RomanoAbstract:We have shown previously that cultured Taenia crassiceps Wake Forest University (WFU) and Taenia solium Cysticerci, as well as the adult worms, synthesize sex steroid hormones from [3H]steroid precursors and that androgens and oestrogens influence the in vitro development of the parasites. Glucocorticoids (GCs) are used to control the inflammation caused by T. solium Cysticerci in the brain. These steroids stimulate oestrogen synthesis in several tissues. Since there is no information on the effect of GC on the endocrine function of Cysticerci, we investigated the effect of natural and synthetic GCs on the synthesis of oestrogens in cultured T. crassiceps WFU Cysticerci. The Cysticerci were obtained from the peritoneal cavity of infected female BALB/c mice; the cysts were washed extensively and pre-cultured in Dulbecco's Modified Eagle's Medium (DMEM) plus antibiotics for 5 days. The parasites were further cultured with different doses of corticosterone, dexamethasone or the vehicle for 5 days. [3H]Dehydroepiandrosterone (3H-DHEA) was added to the media and the Cysticerci were further incubated for 6 or 24 h. Media were then removed and the steroids ether-extracted. Aliquots of the media were seeded on silica gel plates and developed in solvent systems. Parasites incubated in the presence of 3H-DHEA synthesized [3H]androstenediol, [3H]testosterone and [3H]17β-oestradiol ([3H]17β-E2). The addition of 100 nm or higher corticosterone doses to the media increased [3H]17β-E2 synthesis fourfold after 24 h. Dexamethasone also increased [3H]17β-E2 synthesis. The experiments presented here show for the first time that corticosterone and the synthetic GC dexamethasone modulate the synthesis of oestrogens by Cysticerci.
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Antimicrobial peptides (Temporin A and Iseganan IB-367): effect on the Cysticerci of Taenia crassiceps.
Molecular and biochemical parasitology, 2008Co-Authors: Abraham Landa, Kaethe Willms, Lilia Robert, Lucía Jiménez, Luis Felipe Jiménez-garcía, Reyna Lara-martínez, Oscar Cirioni, Wioletta Barańska-rybak, Wojciech KamyszAbstract:Taenia solium infections continue being a health problem in undeveloped countries, and few effective control measures against this parasite are being applied. Antimicrobial peptides (AMPs) belong to the innate immune response and capable of destroying pathogens. We tested the ability of two AMPs, Temporin A (TA) and Iseganan IB-367 (IB-367) to damage T. crassiceps Cysticerci in vitro. Doses of 200 and 400 microg/ml of TA and IB-367 caused Cysticerci to shrink, lose motility, the formation of macrovesicles in the tegument, as well as decreased evagination properties. These changes were observed as early as 3-6h and became more pronounced over 24h, when the morphological changes of the bladders became evident by both light and electron microscopy. Electron micrographs of Cysticerci exposed to peptides showed initial changes as collapsed microvesicles in the tegument, with formation of large vesicles and extrusion of tegumentary tissues into the surrounding media, which led to complete loss of the tegument as well as shrinkage and complete loss of structure of parenchymal tissue after 24h. Peptides administered to cysticercotic mice one month post-infection in a single intraperitoneal dose of 200 or 400 microg, reduced the parasite load by 25% for IB-367, and 50% for TA. The humoral response of infected mice does not appear capable of killing surviving Cysticerci. Our studies show that in vitro, AMPs severely damage the tegument and the scolex, and open a new pathway for biological drug design or the development of transgenic animals that over express these peptides capable of killing the Cysticerci in vivo.
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The key steroidogenic enzyme 3β-hydroxysteroid dehydrogenase in Taenia solium and Taenia crassiceps (WFU)
Parasitology Research, 2008Co-Authors: Ana María Fernández Presas, Kaethe Willms, Ricardo A. Valdez, Marta C. RomanoAbstract:Larval and adult stages of Taenia solium and Taenia crassiceps WFU strain were analyzed by histochemical and biochemical methods to determine the existence of steroid pathways. The presence of the key enzyme 3β-hydroxisteroid-dehydrogenase (3β-HSD) was examined in frozen sections of Cysticerci obtained from mice and segments of tapeworms obtained from the intestine of hamsters. 3β-HSD activity was detected by nitroblue-tetrazolium products after incubation with dehydroepiandrosterone, androstendiol, or pregnenolone. Tapeworm tissues exhibited 3β-HSD activity in the subtegumentary areas of the neck and immature proglottids following incubation with androstendiol, as well as surrounding the testes in mature proglottids. T. solium Cysticerci exhibited 3β-HSD activity in the subtegumentary tissues. The synthesis of steroid hormones involving the activity of 3β-HSD was studied in Cysticerci or tapeworms incubated in the presence of tritiated steroid precursors. The culture media were analyzed by thin layer chromatography and showed synthesis of androstendiol, testosterone, and 17β-estradiol by Cysticerci, androstendiol, and 17β-estradiol by tapeworms. The results strongly suggest the activity of 3β-HSD in taeniid parasites that have at least a part of the enzymatic chain required for androgen and estrogen synthesis and that the enzymes are present in the larval stage and from the early strobilar stages to the mature proglottids.
