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The host’s hormonal environment determines the susceptibility, the course, and severity of several parasite infections. In most cases the infection disturbs the host environment, and activates immune responses that end up affecting the endocrine system. In the other hand, a number of reports indicate that parasites have reproductive systems, and some others have shown that these organisms synthetize sex steroid hormones. We have shown that cysticerci, the larval stage of Taenia solium and Taenia crassiceps ORF and WFU, synthesize steroid hormones. This capacity was modified by drugs that act inhibiting the steroid synthesizing enzymes, or blocking the parasite’s hormone receptors. We have also shown that the cysticerci of T. crassiceps WFU and T. solium have the capacity to synthesize corticosteroids as deoxicorticosterone and corticosterone. We also reviewed the effects of insulin on these parasites, and the receptors found for this hormone. A deep knowledge of the parasite’s endocrine properties will contribute to understand their reproduction and the reciprocal interactions with the host. Likewise, may also help designing tools to combat the infection in clinical situations.

Introduction Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) that mainly affects the lungs. Along the course of pulmonary TB there are remarkable changes in the production of cytokines that cause endocrine changes. So far, it is not known the physiological and histological changes in the male reproductive system during pulmonary TB. Objective To investigate whether pulmonary TB produces histological alterations of the BALB/c mice reproductive organs, as well as abnormalities in spermatogenesis, serum testosterone concentrations and expression of testicular cytokines. Methods BALB/c mice were infected intratracheally with high dose Mtb strain H37Rv. Groups of six non infected and infected animals were euthanized on days 1, 3, 7, 14, 21, 28, 60, 90 and 120 post-infection. Bacillary loads were determined by counting colony forming units (CFUs) in lungs, testes, prostate and seminal vesicles. Histological sections were obtained from the same organs. Spermatozoids number and quality were assessed by spermatobioscopy. Serum testosterone concentrations were determined by radioimmunoanalysis (RIA) in control and infected mice in each time of sacrifice. Results Mtb only grew in lung tissue. Serum androgens showed a trend to decrease in the infected mice compared to the healthy animals, the difference turn into statistically significance at post infection day 120. The weight of the testis was not modified throughout the study, and no histopathological changes were found. However, we detected a significant decrease in the weight of the seminal vesicles and prostate starting at 28 days post-infection. Atrophy of the seminal vesicles and prostate epithelia were significant, beginning after 60 days of infection. Spermatobioscopy revealed hypospermia in the later stages of the disease. We have observed in the testes a local significant disbalance on the cytokine profile (increase of IL-6 and decrease of IL-10 and TGF-b levels) together with a very significant reduction of the body weight during late pulmonary TB. Conclusion Pulmonary TB affects the histophysiology of the male reproductive system due to hormonal changes, an imbalance of pro-inflammatory cytokine profile, and a wasting syndrome during late disease.

One of the most common tools in conservation physiology is the assessment of environmental stress via glucocorticoid measurement. However, little is known of its relationship with other stress related biomarkers, and how the incidence of an immune challenge during a long-term stress could affect individuals overall stress response. We investigated here the relationship between basal and post-acute stress fecal cortisol metabolite (FC) with different antioxidant enzymes, oxidative damage, and immune parameters in the fish-eating Myotis (Myotis vivesi). We found that in both basal and post-stress conditions, FC was highly related to a number of antioxidant enzymes and immune parameters, but no to oxidative damage. We also assessed changes of FC through the seasons. Basal FC samples and stress reactivity after a short-duration stress, displayed similar levels during summer, autumn and early winter, albeit lower concentrations in late winter. Stress reactivity after long-duration stress was greater in summer and early winter. Finally, we tested the effect of a simultaneous exposition to a long-strong-stress stimulus with an immune response stimulation by administrating adrenocorticotropic hormone (ACTH) and phytohemaglutanin (PHA) after 42 h. Results showed that when both stimulus were administrated, FC concentrations, inflammation and some antioxidant activity were lowered in comparison to the control and individual administration of the challenges. Our findings support the idea that animals maintain constant basal GC levels when living in challenging environments, but response to acute stress differs seasonally and immune defense mechanisms and stress response might be compromised when confronted with multiple challenges.

Glioblastoma (GB) is the most common and aggressive primary brain tumor in adult humans. Therapeutic resistance and tumor recurrence after surgical resection contributes to a poor prognosis for glioblastoma patients. Men are known to be more likely than women to develop an aggressive form of GB. Although the reasons for this disparity remain poorly understood, differences in sex steroids have emerged as a leading explanation. Studies indicate that GB-derived cells express androgen receptors (ARs) and synthesize androgens, suggesting that androgens may have a role in the tumor pathogenesis. Thus, our objective was to investigate the effects of the 5α-reductase enzyme inhibitor dutasteride, the AR antagonists cyproterone and flutamide, and combinations of these drugs on the metabolism, proliferation, and invasion capacity of GB-derived U87 cells. We also examined the effects of three natural androgens testosterone, androstenedione and dihydrotestosterone (T, A4, and DHT) on these cells. Cell metabolism was investigated by MTT assay, proliferation was assessed by the bromodeoxyuridine (BrdU) incorporation assay, and invasion was assessed by Boyden chamber assay. The results revealed that T and especially DHT, but not A4, increased U87 cell metabolism and proliferation. Following these findings, we examined the effect of adding dutasteride, cyproterone, or flutamide to the culture media and found that they all significantly decreased cell metabolism and proliferation. Dutasteride also significantly reduced cell invasion. Moreover, any combination of these drugs enhanced their inhibitory effects; the combination of dutasteride to flutamide was most effective at decreasing GB cell proliferation. Our results suggest that administering a combination of AR antagonists and enzyme blockers may be a more effective alternative treatment for GB.

Glioblastoma (GBM) is the most aggressive local brain tumor and effective treatments are lacking. Many studies have proposed an important participation of steroid hormones in the development of gliomas. Evidence was provided by statistics analysis where the incidence in adult population is 50% higher in men than in women. Female patients have a better prognosis for survival compared to male patients with GBM. Also, the expression of receptors to estrogen, progesterone and androgens in glioma cell lines and tumor biopsies, and glucocorticoid receptors in GBM cell lines had been reported. Here we have investigated the effect of the pharmacological inhibition of 5-α reductases on the capacity of GBM derived cell lines C6 (rat) and U87 (human) to synthesize neurosteroids. As the knowledge of the pathways used to synthesize neurosteroids by GBM derived cells was incomplete, we have investigated the synthesis of these steroids by C6 and U87 cells using tritiated precursors and thin layer chromatography (TLC). Increasing concentrations of finasteride and dutasteride were added to U87 culture media that was collected after 24 and 48 h. The results of the study showed that C6 cells incubated with 3H-cholesterol yielded dihydroandrosterone, hydroxytestosterone, androstenediol, androstenedione and estriol, while U87 cells also synthesized progesterone, and androstanedione. Incubation with 3H-androstenedione or 3H-testosterone mainly yielded dihydrotestosterone, androsterone, dihydroandrosterone, hydroxytestosterone, and estradiol in both lines. To note, we showed here for the first time that U87 cells synthesize corticosteroids. Addition of finasteride or dutasteride to U87 cells reduced androgen and estrogen synthesis. Dutasteride also decreased the synthesis of dihydrocorticosterone and allotetrahydrodesoxycorticosterone while deoxycorticosterone was accumulated. In summary, both GBM cell lines synthesize numerous neurosteroids, including 5-α reductase products and 3α-HSD pathways that were inhibited by finasteride and dutasteride. These inhibitors may be considered as tools to control neurosteroid synthesis of potential relevance for GBM survival.

The role of testosterone in males has been extensively studied. However, studies in several species suggest that estrogens are also important for the development and function of male brain, bone, gonads as well as for spermatogenesis and sexual behavior. Data related to testicular P450-aromatase expression and estrogen receptors α and β in several species had been published. However, to our knowledge there is no information on testicular mRNA aromatase expression, estrogen synthesis, or estradiol-17β concentrations in the circulation of the male goat. Thus, the objective of this work was to conduct in vivo and in vitro studies related to estrogen synthesis and serum concentrations during the postnatal testicular development in goat bucks. To do this, circulating concentrations of estradiol-17β and testosterone were evaluated in male goat during the first year of life, starting at 15 days of age. Besides, in order to assess the estrogen-producing ability of testicles from prepubertal male goats (four months), testicular cells were incubated with tritiated androgen precursors ( 3 H-androstenedione and 3 H-testosterone) in the presence or absence of the P450-aromatase inhibitor formestane, using TLC to identify sex steroids. Finally, the expression and tissue distribution of P450-aromatase mRNA in the testis of 3–5 month old males was evaluated by in situ RT-PCR. Results indicate that estradiol-17β is present in the serum of male goats at 0.5 months of age, and that there are significant increases at 3 and 10 months of age. The in vitro synthesis of tritiated estradiol-17β was inhibited by the P450-aromatase inhibitor formestane. Messenger RNA for P450-aromatase was abundantly expressed both in Sertoli cells in the testis of goats of ages three, four and five months. The expression of P450 mRNA was also localized in Leydig cells. It is concluded that the prepubertal goat has measurable quantities of serum estradiol-17β and that their testis has the capacity to synthesize estrogens during this period.

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.

Cysticercosis is a disease caused by the larval stage of Taenia solium cestodes that belongs to the family Taeniidae that affects a number of hosts including humans. Taeniids tapeworms are hermaphroditic organisms that have reproductive units called proglottids that gradually mature to develop testis and ovaries. Cysticerci, the larval stage of these parasites synthesize steroids. To our knowledge there is no information about the capacity of T. solium tapeworms to metabolize progesterone or other precursors to steroid hormones. Therefore, the aim of this paper was to investigate if T. solium tapeworms were able to transform steroid precursors to corticosteroids and sex steroids. T. solium tapeworms were recovered from the intestine of golden hamsters that had been orally infected with cysticerci. The worms were cultured in the presence of tritiated progesterone or androstenedione. At the end of the experiments the culture media were analyzed by thin layer chromatography. The experiments described here showed that small amounts of testosterone were synthesized from 3 H-progesterone by complete or segmented tapeworms whereas the incubation of segmented tapeworms with 3 H-androstenedione, instead of 3 H-progesterone, improved their capacity to synthesize testosterone. In addition, the incubation of the parasites with 3 H-progesterone yielded corticosteroids, mainly deoxicorticosterone (DOC) and 11-deoxicortisol. In summary, the results described here, demonstrate that T. solium tapeworms synthesize corticosteroid and sex steroid like metabolites. The capacity of T. solium tapeworms to synthesize steroid hormones may contribute to the physiological functions of the parasite and also to their interaction with the host.

Risk taking decisions related to the unpredictability of resource availability (risk-sensitive foraging theory) have typically been explained by behavioral ecology and psychology approaches. However, little attention has been given to the physiological condition of animals as a factor that can infl uence the direction of foraging preferences. We evaluated the role of steroid hormones testosterone (T) and corticosterone (CORT) on the foraging preferences expressed by white-eared hummingbirds Hylocharis leucotis in a risk-sensitivity experiment. We recorded choices made by male individuals to fl oral arrays with constant and variable rewards (sugar concentration), and associated these with steroid hormone levels quantifi ed at the start of the experiments. We found that males with higher T levels behave as risk-prone foragers as they perform more visits to fl ower arrays with variable rewards. Interestingly, CORT levels were similar regardless whether individuals visited both types of array. According to our results, T seems to infl uence the foraging preferences of male hummingbirds. Individuals with higher levels of this hormone, made more rapid, frequent visits to fl owers with variable rewards, and behave consistently as risk-prone foragers, compared to males with low T levels. Th ese are exciting avenues for future work, particularly considering recent evidence that individuals may exhibit behavioral diff erences, denoting an apparent personality, which may be associated with phisiological condition infl uencing how they respond behaviorally to environmental variation.

Few studies have been carried out on the welfare of captive bottlenose dolphins (Tursiops truncatus). Of these, most include information on animals kept in closed facilities or pools. The aim of this study was to assess the welfare of captive bottlenose dolphins in open and closed facilities by measuring states of individual behavior and salivary cortisol concentrations. A total of 23 bottlenose dolphins were studied in 4 different dolphinaria. Dolphinaria A and B have closed facilities, whereas dolphinaria C and D have open facilities. A total of 152 hours of behavioral observations were analyzed using a combination of behavior and scan sampling to obtain information on individual time budgets. Salivary cortisol concentrations were measured using radioimmunoassay in 96 and 180 saliva samples of dolphins kept in closed and open facilities, respectively. In general, the results found that dolphins kept in open facilities spent less time floating (P < 0.05) and swimming in circular patterns than linear ones (P < 0.05) compared with dolphins in closed facilities. Dolphins kept in open facilities also had lower salivary cortisol concentrations than dolphins kept in closed facilities (P < 0.05). For this reason, we suggest that further research should include other welfare indicators such as reproductive function and health measurements to know more about the relationships between the design of pools and dolphin welfare.

In this study we measured two physiological traits (levels of corticosterone and immunoglobulin) in two species of landbirds, the Canyon Towhee (Melozone fusca) and Inca Dove (Columbina inca), occupying three degrees of human alteration of a subtropical mountain landscape: forest edges, croplands, and urban sites. We found that both physiological variables differed by species and habitat condition. In both species, corticosterone concentration was significantly higher in croplands. But immunoglobulin concentration behaved differently, in C. inca being highest at urban sites, where in M. fusca it was lowest. Contrary to expectation, we only found one strong significant relationship between both physiological variables: M. fusca in urban areas. Our results suggest that 30% of the towhees captured in urban areas are under chronic stress. Results for body condition support this hypothesis, as the condition of towhees in urban areas was poorer, suggesting physiological vulnerability. Although we expe...

In some species, including swine, cattle and sheep, the placenta synthesizes all the enzymes needed to convert cholesterol into progestagen and estrogen. However, in goat reproduction the processes specific to and the knowledge of goat placental steroidogenesis is unclear. Therefore, the objective of the present study was to investigate the steroidogenic pathways used by the goat placenta to synthesize androgens and estrogens, with special emphasis on androgen production. Five postpartum placentas obtained immediately after expulsion were processed for the study. A cell suspension was prepared from excised cotyledons and aliquots incubated in DMEM and antibiotics, and 3 H-progesterone, 3 H-dehydroepiandrosterone, 3 H-androstenedione or 3 H-testosterone. Steroids were extracted from the culture media and analyzed by thin layer chromatography (TLC). Testosterone and androstendione were then recrystallized from the placenta incubation media. Placental tissue was processed for in situ -RT-PCR in order to investigate the expression of 17α-hydroxylase/17,20 lyase. Results showed the synthesis of tritiated androgens and estrogens when cells were incubated with 3 H-progesterone. The incubation with 3 H-testosterone or 3 H-androstenedione yielded 3 H-17β-oestradiol and 3 H-oestrone. Placental cells also transformed 3 H-DHEA to the androgens 3 H-androstenedione, 3 H-androstenediol and 3 H-testosterone and also to 3 H-estrogens. Androstendione and testosterone synthesis were re-confirmed by recristallization. The results of this study show that goat placental cells may use both the Δ-4 and the Δ-5 steroidogenic pathways to synthesize androgens and estrogens. These data show the steroidogenic pathways used by the goat placenta to yield androgens, and the ability of both androstendione and testosterone to be converted into estrogens for the first time.

The effect of zoo visitors on the behaviour and physiological responses of the Mexican wolf has not been documented but is worthy of investigation since it is a critically endangered native species and most of the population live in zoos. The effect of the number of visitors was assessed in 12 wolves (five males and seven females) in three zoos of central Mexico. Each wolf was observed for a total of 72 h on Saturdays, Sundays, Mondays and Tuesdays (6 h/day) during a three-week period. Scan sampling was used to obtain individual time budgets. A faecal sample was collected on the following morning of each observation day from 10 wolves to determine cortisol level (RIA). A repeated measures analysis of variance revealed that there was an effect of day on the proportion of time lying (P

Urbanization generates human-made habitats with novel resources. Such change is not homegeneous, and includes different urban land uses characterized by specific habitat traits. In this study we explored the ecophysiologial response of an urban-exploiter species in three different urban land uses (urban, suburban, industrial). Our results show that corticosterone (obtained through fecal samples) and immunoglobulin (obtained through blood samples) concentrations did not differ significantly among the studied urban land uses. Corticosterone and immunoglobulin concentration showed both high and low values in urban and suburban areas, while industrial areas had low and high levels of corticosterone, and medium-to-low immunoglobulin concentration values. Also, we found a negative relationship between corticosterone and immunoglobulin concentrations in industrial areas. Based on corticosterone and immunoglobulin concentration thresholds established from previous studies, our results suggest that: (1) birds in the three studied urban conditions are both stressed and non-stressed; and (2) the immune system of industrial House Sparrows could not be responding successfully to pathogens. Not finding physiological relationships in urban and suburban areas underline that this species has a large capacity to respond to the different stress and immune challenges found in urban areas. However, our results suggest that the physiological condition of industrial House Sparrows could be compromised by differences in the frequency and intensity of the stressor agents faced by the birds in this land use category.

Depression and stress are related pathologies extensively studied in humans. However, this relationship is not well known in animals kept in zoos and even less known in wild animals. In zoo animals, acute and chronic stress caused by difficulties in coping with stressors such as public presence and noise, among others, can induce the appearance of repetitive pathological behaviors such as stereotypies, many times associated with organic pathologies that deeply affect their health and welfare. In the wild, factors such as deforestation, habitat fragmentation, lack of food and water, and human disturbances are potential causes of acute and chronic stress for the resident fauna. Glucocorticoids (GC) have been extensively used as stress indicators in many species including humans. Since chase and handling of wild animals immediately raise their GC serum levels, noninvasive methods have been developed to assess stress without interference caused by sample collection. The hormones and their metabolites can be measured in various body fluids and excreta and detect basal feedback free hormone concentrations as well as the response to ACTH and handling. In order to study the influence of disturbing factors we have measured GC as stress indicators by noninvasive techniques in dolphins and felids (ocelots, jaguarundis and margays) and cortisol and testosterone in spider monkeys.

exico Abstract In the Yucat ´ an Peninsula, spider monkeys Ateles geoffroyi yucatanensis are generally found in two contrasting conditions: large tracts of conserved forest or small fragments surrounded by human populations. In the present study, we analyzed fecal cortisol levels of spider monkeys to investigate whether environ- mental conditions have an influence on stress; specifically, we compared fecal cortisol across individuals living in conserved forests, fragmented forests and captive conditions (zoos and pets). Radioimmunoanalysis of fecal samples from 121 individuals indicated significant differences in mean cortisol for A. g. yucatanensis based on habitat type, with the lowest levels found in the conserved forest condition. The higher cortisol levels in both fragmented forest populations and in captive individuals may be the result of metabolic and behavioral stress. The mean male fecal cortisol concentration was significantly higher than that of females, and the fecal cortisol concentration was higher in the dry season compared with the wet season in a conserved habitat. Therefore, we emphasize the importance of considering sex and seasonality when monitoring fecal cortisol concentrations of spider monkeys, and more generally of frugivores, as they face a seasonal variation in food availability. Finally, our results suggest that forest fragmentation may create long-term stressors for spider monkeys, affecting the viability of populations living under such conditions.

Over the last years the biology of many parasites that infect humans and domestic animals has been intensively studied. Considerable efforts were addressed to obtain information on the parasite-host immune relationship. However, the knowledge of the endocrine physiology of parasites and the consequences of the local hormone production on the host tissues needs further investigation. We review here literature and our own studies on endocrine parasite capacities with special emphasis on cysticercosis. Besides the biological interest, these investigations may contribute to identify in the future alternative treatments for the disease.

The rapid loss, fragmentation and degradation of tropical forests threaten the survival of many animal species. However, the way in which these phenomena affect animal health has been poorly explored, thus limiting the design of appropriate conservation strategies. To address this, here we identified using linear mixed models the effect of proximal (diet, activity pattern, hunting and logging) and distal (sum of the basal areas of fruiting-tree species [SBAFS], landscape forest cover and degree of forest fragmentation) variables over fecal glucocorticoid metabolite (fGCM) levels–hormones associated with animal health and fitness–of six groups of spider monkeys (Ateles geoffroyi) inhabiting six landscapes with different spatial structures in Mexico. Proximal variables showed a stronger predictive power over fGCMs than distal. In this sense, increases in travel time, the occurrence of hunting, and reductions in rest time and fruit consumption resulted in higher fGCM levels. Regarding distal variables, increases in SBAFS were negatively related to fGCM levels, thus suggesting that food scarcity increases stress hormone levels. Nevertheless, contrary to theoretical expectations, spider monkeys living in smaller tracts of forest spent less time travelling, but the same time feeding on fruit as those in more forested areas. The lower net energy return associated with this combination of factors would explain why, contrary to theoretical expectations, increased forest cover was associated with increased levels of fGCMs in these groups. Our study shows that, at least in the short term, spider monkeys in fragmented landscapes do not always present higher levels of stress hormones compared to those inhabiting continuous forest, and the importance of preserving fruit sources and controlling hunting for reducing the levels of stress hormones in free ranging spider monkeys.

In many cases parasites display highly complex life cycles that include the penetration and permanence of the larva or adults within host organs, but even in those that only have one host, reciprocal, intricate interactions occur. Evidence indicates that steroid hormones have an influence on the development and course of parasitic infections. The host gender's susceptibility to infection, and the related differences in the immune response are good examples of the host-parasite interplay. However, the capacity of these organisms to synthesize their own steroidogenic hormones still has more questions than answers. It is now well-known that many parasites synthesize ecdysteroids, but limited information is available on sex steroid and corticosteroid synthesis. This review intends to summarize some of the existing information in the field. In most, but not all parasitosis the host's hormonal environment determines the susceptibility, the course, and severity of parasite infections. In most cases the infection disturbs the host environment, and activates immune responses that end up affecting the endocrine system. Furthermore, sex steroids and corticosteroids may also directly modify the parasite reproduction and molting. Available information indicates that parasites synthesize some steroid hormones, such as ecdysteroids and sex steroids, and the presence and activity of related enzymes have been demonstrated. More recently, the synthesis of corticosteroid-like compounds has been shown in Taenia solium cysticerci and tapeworms, and in Taenia crassiceps WFU cysticerci. In-depth knowledge of the parasite's endocrine properties will contribute to understand their reproduction and reciprocal interactions with the host, and may also help designing tools to combat the infection in some clinical situations.

Fast-growing mycobacteria such as Mycobacterium sp. and Mycobacterium smegmatis degrade natural sterols. They are a model to study tuberculosis. Interestingly, M. smegmatis has been found in river effluents derived from paper production, and therefore, it would be important to gain further insight into its capacity to synthesize steroids that are potential endocrine disruptors affecting the development and reproduction of fishes. To our knowledge, the capacity of M. smegmatis to synthesize estrogens and even testosterone has not been previously reported. Therefore, the objective of this study was to investigate the capacity of M. smegmatis to synthesize in vitro testosterone and estrogens from tritiated precursors and to investigate the metabolic pathways involved. Results obtained by thin-layer chromatography showed that3H-progesterone was transformed to 17OH-progesterone, androstenedione, testosterone, estrone, and estradiol after 6, 12, or 24 h of incubation.3H-androstenedione was transformed into testosterone and estrogens, mainly estrone, and3H-testosterone was transformed to estrone and androstenedione. Incubation with3H-dehydroepiandrosterone rendered androstenediol, testosterone, and estrogens. This ability to transform less potent sex steroids like androstenedione and estrone into other more active steroids like testosterone and estradiol or vice versa suggests that M. smegmatis can influence the amount of self-synthesized strong androgens and estrogens and can transform those found in the environment.

Cysticerci from Taenia solium develop in the pig muscle and cause severe diseases in humans. Here we report on the capacity of T. solium cysticerci to synthesize sex steroid hormones. T. solium cysticerci were dissected from infected pork meat. Parasites were incubated for different periods in culture media plus antibiotics and tritiated steroid precursors. Blanks and parasite culture media were extracted and analyzed by thin-layer chromatography (TLC) in two different solvent systems. In some experiments, the scoleces were incubated separately. Results showed that T. solium cysticerci transform [(3)H]androstenedione to [(3)H]testosterone in a time-dependent manner. The production was confirmed in two different solvent systems. The incubation with [(3)H]testosterone yielded only small amounts of [(3)H]androstenedione. The recrystallization procedure further demonstrated that the metabolite identified by TLC was testosterone. The isolated scoleces incubated in the presence of [(3)H]androstenedione yielded [(3)H]testosterone and small quantities of [(3)H]17beta-estradiol. The results reported here demonstrate that T. solium cysticerci have the capacity to synthesize steroid hormones.

Environmental enrichment can be a useful tool to reduce belly nosing behaviors in early weaned piglets. The aim of this study was to assess the effect of environmental enrichment on behavior, salivary cortisol, and productivity of piglets weaned at 14 days of age. The study assigned 112 piglets (line Camborough 22 of PIC) into 2 treatments, control and enriched, and observed them for 192 hr in 3 periods: 14 to 28 days of age (Phase 1), 28 to 42 days of age (Phase 2), and 42 to 54 days of age (Phase 3). The study obtained saliva samples in each phase from 56 piglets selected randomly from each group for cortisol determination. Comparisons between both treatments and phases included the following: proportion of time belly nosing, latency of approaching a person, average levels of salivary cortisol, and daily weight gain. Belly nosing was higher and latency of approaching a person lower in the control group than in the enriched one (p.05 and p.01). Belly nosing was lower in Phase 3 (p.05); latency of approaching a person was higher in Phase 1 with respect to Phase 2, and this was higher with respect to Phase 3 (p.01). There were no differences in salivary cortisol levels between treatments or phases. Weight gain was higher in the enriched group (p.001). Environmental enrichment in piglets weaned at 14 days of age resulted in a reduced proportion of time nosing, reduced latency of response to humans, and better growth than piglets in barren environments.

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.

Sex hormones are known to modulate immune responses and may be implicated in sex associated susceptibilities to infections. Taenia crassiceps cysticerci grow to larger numbers in female mice than in males. Gonadectomy alters the course of this infection and hormone replacement with 17β-estradiol increases the parasite numbers. However, in chronic Taenia crassiceps cysticercosis the sex-hormone profile of males becomes more like that of the females' and progressively loose their sexual behavior. To have further insight in these outstanding endocrinological effects induced by the parasite upon the host, we investigated the parasite's capacity to produce sex steroids. In vitro experiments showed that Taenia crassiceps cysticerci transform 3H-Androstenedione to 3H-Testosterone, but not 3H-Pregnenolone. The production of 3H-Testosterone increased when the parasite numbers doubled. A recrystallisation procedure demonstrated that the metabolite identified by TLC was in fact testosterone. Thus, the cysticercus has the ability to use 3H-Androstenedione to make Testosterone possibly by a 17β-Hydroxysteroid deshidrogenase-like activity in the parasite. In vivo, the parasite could use steroid precursors from the host to produce sex hormones, either accidentally or as needed for its own development, and thus alters the host's normal environment with sexual and immunological repercussions.

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.

International audience; Neurocysticercosis (NC) is a parasitic disease caused by the infiltration of the larval stage of Taenia solium in the central nervous system. Clinical presentations are heterogeneous and particularly depend, on the age and gender of the host. We designed a clinical study to evaluate the hormonal changes associated with neurocysticercosis and the relationships between disease heterogeneity, endocrine and immunological status. A total of 50 patients and 22 healthy subjects were included. A precise clinical and radiological description of disease for each patient was recorded. A broad hormonal profile was assessed for each participant and, in a sub-group of patients, immunological features were also evaluated. Compared with controls, all patients had lower dehydroepiandrosterone (DHEA) concentration; male patients also had lower concentrations of 17β-estradiol and higher concentrations of luteinising hormone (LH). In the clinically severe patients, lower concentrations of progesterone and androstenedione were found in women. Higher concentrations of follicle stimulating hormone (FSH) and lower concentrations of testosterone were found in men when compared with the less clinically severe patients. Significant correlations were found between estradiol and IL-10 in male patients, and between dehydroepiandrosterone (DHEA) and IL-1β, and androstenedione and IL-17 in female patients. To our knowledge the present study constitutes the first demonstration that the presence of T. solium larvae in the central nervous system can modify the host environment by the induction of endocrine and immunological changes. These results provide a stimulating background to analyse the repercussions of these changes on the course of the disease and on patient reproductive health.

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.

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.

American Trypanosomiasis is caused by the hemoflagellate Trypanosoma cruzi ( T. cruzi ) and affects millions of persons causing variable degrees of digestive and heart disturbances. As far as we concerned, T. cruzi capacity to synthesize steroid hormones has not been investigated. Therefore, the aim of this work was to investigate the capacity of T. cruzi trypomastigotes to transform tritiated steroid precursors into androgens and estrogens. The T. cruzi Tulahuen strain was obtained from mice blood. The trypomastigotes were cultured for 6 and 24 h in Dulbbeco’s modified Eagle's medium plus FCS and antibiotics. Tritiated dehydroepiandrosterone or androstendione were added to the culture media and parasites were incubated for 6 or 24 h. The cultures were centrifuged and ether extracted. The steroids were analyzed by thin layer chromatography (TLC) in two solvent systems. After incubation with 3 H-androstenedione, T. cruzi trypomastigotes synthesized 3 H-testosterone (T), 3 H-17β-estradiol (E 2 ) and 3 H-estrone (E 1 ). Metabolism of 3 H-DHEA by the parasites yielded 3 H-androstendione and 3 H-androstendiol at 6 h of incubation. The recrystallization procedure further demonstrated the 3 H-androstendiol and 3 H-17β-estradiol syntheses. Results indicate for the first time that T. cruzi trypomastigotes produce androgens and estrogens when incubated in the presence of steroid precursors and suggest the presence of active parasite steroidogenic enzymes.

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 3beta-hydroxisteroid-dehydrogenase (3beta-HSD) was examined in frozen sections of cysticerci obtained from mice and segments of tapeworms obtained from the intestine of hamsters. 3beta-HSD activity was detected by nitroblue-tetrazolium products after incubation with dehydroepiandrosterone, androstendiol, or pregnenolone. Tapeworm tissues exhibited 3beta-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 3beta-HSD activity in the subtegumentary tissues. The synthesis of steroid hormones involving the activity of 3beta-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 17beta-estradiol by cysticerci, androstendiol, and 17beta-estradiol by tapeworms. The results strongly suggest the activity of 3beta-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.