108 Fecal metabolite monitoring as a tool to assess sexual maturation in polar bears

2019 ◽  
Vol 31 (1) ◽  
pp. 180
Author(s):  
E. Curry ◽  
M. A. Stoops ◽  
T. L. Roth

Polar bears (Ursus maritimus) in managed care generally are paired for breeding starting around the age of 5 or 6 years; however, DNA analyses of the wild population indicate that males as young as 2 or 3 may sire offspring and females as young as 4 can produce cubs. There are no reports describing longitudinal reproductive hormone parameters in juvenile polar bears. The objective of the current study was to determine if seasonal shifts in testosterone and progesterone (P4) metabolites are detectable in feces of polar bears 2-3 years old as part of a greater effort to characterise reproductive metabolites in a large cohort of juveniles throughout sexual maturation. Subjects were 2-year-old male (n=3) and female (n=3) polar bears residing at 5 zoological institutions in the USA. Individuals were monitored for 1 (1.1) or 2 (2.2) years. Fecal samples were collected noninvasively 3-4 times/week and hormone metabolites were extracted as previously described. Testosterone was evaluated as an indicator of gonadal activity in both sexes, whereas P4 was measured in samples collected from females only. Metabolites were quantified in duplicate using established enzyme immunoassay techniques. Student’s and paired t-tests were used to compare mean metabolite concentrations between seasons [breeding (BS; January-June) and nonbreeding (NBS; July-December)] by sex and within individual, respectively. All values are reported as mean concentration (ng metabolite/g dried feces±standard error of the means) and P-values less than 0.05 indicated statistical significance. Mean testosterone concentration of the 2-year-old males was 153.1±112.5. Overall, testosterone concentrations were higher in samples collected from 2-year-old males during BS versus NBS; however, when examined within individual, this held true for only 1 of 3 males. Mean testosterone of the 3-year-old male was 170.2±19.6 and values were significantly higher in BS (282.1±27.2) versus NBS (74.6±7.3). The overall mean testosterone and P4 concentrations of the 2-year-old females were 56.0±21.7 and 57.4±7.5, respectively. Two of the 3 females exhibited significantly higher testosterone concentrations during BS compared to NBS and all 3 exhibited higher P4 in the breeding versus the NBS. The 3-year-old female had significantly higher testosterone in BS (63.7±4.1) versus NBS (40.5±2.4) and showed evidence of regular ovarian cycles during BS. Despite no detectable differences in mean P4 between seasons (56.3±7.9 and 55.1±3.7), this female exhibited a distinct increase in P4 from October to November compared to the rest of NBS (85.7±8 v. 43.5±2.8), suggestive of pseudopregnancy. These results indicate that fecal reproductive hormone metabolite monitoring can be used to detect changes in metabolite excretion patterns associated with sexual maturation in polar bears and that males and females as young as 2 years old may exhibit seasonal variations in reproductive hormones. These data suggest bears in zoological institutions may be achieving sexual maturation earlier than believed previously and should be considered when managing bears in human care.

2020 ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  

Abstract Background: Endocrine disrupting chemicals (EDCs) such as metals have been reported to alter circulating reproductive hormone concentrations and pubertal development in animals. However, the relationship has rarely been investigated among humans, with the exception of heavy metals, such as Pb and Cd. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone levels and sexual maturation and progression among boys from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts.Methods: Our analysis included 118 pregnant women and their male children from the ELEMENT study. Essential and non-essential metals were measured in urine collected from the mothers during the third trimester of pregnancy and their male children at 8-14 years. Reproductive hormone levels [serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG)] were measured in blood samples from the children at 8-14 years. We also assessed Tanner stages for sexual maturation (genital, pubic hair development, and testicular volume), at two time points (8–14, 10-18 years). We used linear regression to independently examine urinary metal levels in relation to each peripubertal reproductive hormones adjusting for child age and BMI. Generalized estimation equations (GEEs) were used to evaluate the association of in utero and peripubertal metal exposures with sexual maturation and progression during follow-up based on Tanner staging and testicular volume.Results: In utero and prepubertal concentrations of some urinary metals were associated with increased levels of peripubertal reproductive hormones, especially non-essential metal(loid)s As and Cd (in utero), and Ba (peripubertal) as well as essential metal Mo (in utero) in association with testosterone. More advanced pubic hair developmental stage and higher testicular volume at the early teen visit was observed for boys with higher non-essential metal concentrations, including in utero Al and peripubertal Ba, and essential metal Zn concentration (peripubertal). These metals were also associated with slower pubertal progression between the two visits.Conclusion: These findings suggest that male reproductive development may be associated with both essential and non-essential metal exposure during in utero and peripubertal windows.


2013 ◽  
Vol 82 (1) ◽  
pp. 91-96
Author(s):  
Ignacio Ayala ◽  
Nieves Martos

The aim of this work was to measure serum concentrations of dehydroepiandrosterone, androstenedione, testosterone and 17β-oestradiol in horses with various diseases and after surgery. We hypothesize that diseases and castration could potentially affect concentrations of steroid reproductive hormones. Blood samples were obtained from six groups of horses comprising a total of 119 horses (75 males and 44 females, 5–15 years old) with laminitis, acute abdominal syndrome, acute diseases, chronic diseases, after castration and healthy control. Hormone concentrations in serum were determined for each group using competitive enzyme immunoassay. Significant increases compared to control were found for dehydroepiandrosterone in horses with castration (P < 0.01), acute abdominal syndrome and acute diseases (P < 0.05). Besides, significant increases were observed for androstenedione in horses with laminitis, castration and acute diseases (P < 0.01), and in acute abdominal syndrome and chronic diseases (P < 0.05). Significant increases were also found for testosterone in horses with castration (P < 0.01) and with laminitis, acute abdominal syndrome and chronic diseases (P < 0.05). The lowest values of testosterone were found in the control group. Compared to control, 17b-oestradiol serum concentrations showed significant decreases (P < 0.01) in horses with laminitis, acute abdominal syndrome, acute and chronic diseases. Significant differences (P < 0.05) for the four studied hormones were found between males and females in each group. Our results showed that there were significant differences in steroid reproductive hormone concentrations in diseased horses and in those after surgery, compared to controls.


2020 ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  

Abstract Background: Endocrine disrupting chemicals (EDCs) such as metals have been reported to alter circulating reproductive hormone concentrations and pubertal development in animals. However, the relationship has rarely been investigated among humans, with the exception of heavy metals, such as Pb and Cd. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone levels and sexual maturation and progression among boys from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts.Methods: Our analysis included 118 pregnant women and their male children from the ELEMENT study. Essential and non-essential metals were measured in urine collected from the mothers during the third trimester of pregnancy and their male children at 8-14 years. Reproductive hormone levels [serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG)] were measured in blood samples from the children at 8-14 years. We also assessed Tanner stages for sexual maturation (genital, pubic hair development, and testicular volume), at two time points (8–14, 10-18 years). We used linear regression to independently examine urinary metal levels in relation to each peripubertal reproductive hormones adjusting for child age and BMI. Generalized estimation equations (GEEs) were used to evaluate the association of in utero and peripubertal metal exposures with sexual maturation and progression during follow-up based on Tanner staging and testicular volume.Results: In utero and prepubertal concentrations of some urinary metals were associated with increased levels of peripubertal reproductive hormones, especially non-essential metal(loid)s As and Cd (in utero), and Ba (peripubertal) as well as essential metal Mo (in utero) in association with testosterone. More advanced pubic hair developmental stage and higher testicular volume at the early teen visit was observed for boys with higher non-essential metal concentrations, including in utero Al and peripubertal Ba, and essential metal Zn concentration (peripubertal). These metals were also associated with slower pubertal progression between the two visits.Conclusion: These findings suggest that male reproductive development may be associated with both essential and non-essential metal exposure during in utero and peripubertal windows.


2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  

Abstract Background Endocrine disrupting chemicals (EDCs) such as metals have been reported to alter circulating reproductive hormone concentrations and pubertal development in animals. However, the relationship has rarely been investigated among humans, with the exception of heavy metals, such as Pb and Cd. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone concentrations and sexual maturation and progression among boys from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts. Methods Our analysis included 118 pregnant women and their male children from the ELEMENT study. Essential and non-essential metals were measured in urine collected from the mothers during the third trimester of pregnancy and their male children at 8–14 years. Reproductive hormone concentrations [serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG)] were measured in blood samples from the children at 8–14 years. We also assessed Tanner stages for sexual maturation (genital, pubic hair development, and testicular volume), at two time points (8–14, 10–18 years). We used linear regression to independently examine urinary metal concentrations in relation to each peripubertal reproductive hormones adjusting for child age and BMI. Generalized estimation equations (GEEs) were used to evaluate the association of in utero and peripubertal metal exposures with sexual maturation and progression during follow-up based on Tanner staging and testicular volume. Results In utero and prepubertal concentrations of some urinary metals were associated with increased concentrations of peripubertal reproductive hormones, especially non-essential metal(loid)s As and Cd (in utero), and Ba (peripubertal) as well as essential metal Mo (in utero) in association with testosterone. More advanced pubic hair developmental stage and higher testicular volume at the early teen visit was observed for boys with higher non-essential metal concentrations, including in utero Al and peripubertal Ba, and essential metal Zn concentration (peripubertal). These metals were also associated with slower pubertal progression between the two visits. Conclusion These findings suggest that male reproductive development may be associated with both essential and non-essential metal exposure during in utero and peripubertal windows.


1985 ◽  
Vol 248 (1) ◽  
pp. E126-E131
Author(s):  
A. C. Dalkin ◽  
J. A. Duncan ◽  
S. Regiani ◽  
J. C. Marshall

The number of pituitary gonadotropin-releasing hormone (GnRH) receptors increases during sexual maturation in the rat and probably reflects changes in hypothalamic GnRH secretion. As GnRH is synthesized in various hypothalamic nuclei, including the arcuate nucleas (ARC), we investigated the effects of monosodium glutamate (MSG)-induced lesions of the ARC in the rat. In males and females treated with MSG during the first 10 days of life, GnRH receptor content (GnRH-RC) was unchanged from controls at 10 days but was decreased at 20 and 30 days of age (P less than 0.01). Serum concentrations of luteinizing hormone (LH) were similar in MSG-treated and control males but were significantly lower in 10-day-old females (P less than 0.01). Injections of GnRH (3 micrograms every 8 h on days 18 and 19) restored GnRH-RC to control values in MSG-treated rats. Both MSG and untreated control rats showed similar LH responses to acute injections of GnRH, but responses were attenuated (P less than 0.05) after 2 days pretreatment with GnRH in rats that had received MSG. Ovarian GnRH-RC was similar in both MSG-treated and untreated controls. These data indicate that MSG-induced lesions of the ARC reduce pituitary GnRH-RC in immature rats, and the more marked effects in females suggest a more significant role in the ARC in the control of GnRH secretion during maturation in females. The lack of MSG-induced changes in ovarian GnRH-RC indicates that GnRH from the arcuate nucleus is not responsible for the increase in ovarian GnRH receptors seen during sexual maturation.


2020 ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  

Abstract Background: Endocrine disrupting chemicals (EDCs) such as metals have been reported to alter circulating reproductive hormone concentrations and pubertal development in animals. However, the relationship has rarely been investigated among humans, with the exception of heavy metals, such as Pb and Cd. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone concentrations and sexual maturation and progression among boys from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts.Methods: Our analysis included 118 pregnant women and their male children from the ELEMENT study. Essential and non-essential metals were measured in urine collected from the mothers during the third trimester of pregnancy and their male children at 8-14 years. Reproductive hormone concentrations [serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG)] were measured in blood samples from the children at 8-14 years. We also assessed Tanner stages for sexual maturation (genital, pubic hair development, and testicular volume), at two time points (8–14, 10-18 years). We used linear regression to independently examine urinary metal concentrations in relation to each peripubertal reproductive hormones adjusting for child age and BMI. Generalized estimation equations (GEEs) were used to evaluate the association of in utero and peripubertal metal exposures with sexual maturation and progression during follow-up based on Tanner staging and testicular volume.Results: In utero and prepubertal concentrations of some urinary metals were associated with increased concentrations of peripubertal reproductive hormones, especially non-essential metal(loid)s As and Cd (in utero), and Ba (peripubertal) as well as essential metal Mo (in utero) in association with testosterone. More advanced pubic hair developmental stage and higher testicular volume at the early teen visit was observed for boys with higher non-essential metal concentrations, including in utero Al and peripubertal Ba, and essential metal Zn concentration (peripubertal). These metals were also associated with slower pubertal progression between the two visits.Conclusion: These findings suggest that male reproductive development may be associated with both essential and non-essential metal exposure during in utero and peripubertal windows.


2020 ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  

Abstract Background Endocrine disrupting chemicals (EDCs) such as metals have been reported to alter circulating reproductive hormone concentrations and pubertal development in animals. However, the relationship has rarely been investigated among humans, with the exception of heavy metals, such as Pb and Cd. Our aim was to investigate measures of in utero and peripubertal metal exposure in relation to reproductive hormone levels and sexual maturation and progression among boys from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohorts. Methods Our analysis included 118 pregnant women and their male children from the ELEMENT study. Essential and non-essential metals were measured in urine collected from the mothers during the third trimester of pregnancy and their male children at 8-14 years. Reproductive hormone levels [serum testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), inhibin B, and sex hormone-binding globulin (SHBG)] were measured in blood samples from the children at 8-14 years. We also assessed Tanner stages for sexual maturation (genital, pubic hair development, and testicular volume), at two time points (8–14, 10-18 years). We used linear regression to independently examine urinary metal levels in relation to each peripubertal reproductive hormones adjusting for child age and BMI. Generalized estimation equations (GEEs) were used to evaluate the association of in utero and peripubertal metal exposures with sexual maturation and progression during follow-up based on Tanner staging and testicular volume. Results In utero and prepubertal concentrations of some urinary metals were associated with increased levels of peripubertal reproductive hormones, especially non-essential metal(loid)s As and Cd ( in utero ), and Ba (peripubertal) as well as essential metal Mo ( in utero ) in association with testosterone. More advanced pubic hair developmental stage and higher testicular volume at the early teen visit was observed for boys with higher non-essential metal concentrations, including in utero Al and peripubertal Ba, and essential metal Zn concentration (peripubertal). These metals were also associated with slower pubertal progression between the two visits. Conclusion These findings suggest that male reproductive development may be associated with both essential and non-essential metal exposure during in utero and peripubertal windows.


Pharmacy ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 76
Author(s):  
Syed Faisal Zaidi ◽  
Rayan Mgarry ◽  
Abdullah Alsanea ◽  
Sakar Khalid Almutairi ◽  
Yaser Alsinnari ◽  
...  

Introduction: Various drug–food interactions exist that may hinder treatment and can sometimes be lethal. Our aim was to assess the level of public knowledge and awareness in Jeddah city, Western Saudi Arabia, about drug–food interactions, along with the effects of demographics on their knowledge. Methods: A survey questionnaire was administered in this cross-sectional study to participants spread across multiple locations in Jeddah, including in malls and public gatherings. Participants included both males and females. Sample size was calculated through Raosoft® software. Data analysis was executed using IBM Statistic SPSS and the level of statistical significance was set at p < 0.05. Results: A total of 410 people participated in the study and only 92.68% (380) of responses were enrolled in the study; 7.32% (30) were not enrolled due to the exclusion criteria. Surprisingly, only six out of eighteen questions regarding drug–food interactions in the administered questionnaire were correctly answered by 380 participants. Data indicated that the participants had a poor to intermediate level of both knowledge and awareness with respect to drug–food interactions. Furthermore, participants showed moderate to strong awareness of the effects of alcohol and tea generally, and their interaction with medication. Conclusion: Participants in our study showed inadequate knowledge of basic and fundamental information about drug–food interactions, which highlights the dire need to increase awareness.


Author(s):  
Helen B Chin ◽  
Andrea Kelly ◽  
Margaret A Adgent ◽  
Stacy A Patchel ◽  
Kerry James ◽  
...  

Abstract Context Soy formula feeding is common in infancy and is a source of high exposure to phytoestrogens, documented to influence vaginal cytology in female infants. Its influence on minipuberty in males has not been established. Objective To assess the association between infant feeding practice and longitudinally measured reproductive hormones and hormone-responsive tissues in infant boys. Design The Infant Feeding and Early Development study was a prospective cohort of maternal-infant dyads requiring exclusive soy formula, cow-milk formula, or breastmilk feeding during study follow-up. Reproductive hormone concentrations and male anatomical measurements were longitudinally assessed from birth to 28 weeks. Setting Clinic-based cohort Participants 147 mother-infant boy pairs Interventions not applicable Main outcome measure Serum testosterone and luteinizing hormone (LH) concentrations, stretched penile length, anogenital distance, and testis volume. Results Median serum testosterone was at pubertal levels at 2 weeks [176 ng/dL (quartiles:124, 232)] and remained in this range until 12 weeks, in all feeding groups. We did not observe differences in trajectories of hormone concentrations or anatomical measures between boys fed soy formula (n=55) and boys fed cow-milk formula (n=54). Compared with breastfed boys (n=38), soy-formula-fed boys had a more rapid increase in penile length (p=0.004) and slower initial lengthening of AGD (p=0.03), but no differences in hormone trajectories. Conclusions Reproductive hormone concentrations and anatomical responses followed similar trajectories in soy and cow-milk formula-fed infant boys. Our findings suggest that these measures of early male reproductive development do not respond to phytoestrogen exposure during infancy.


Nematology ◽  
2021 ◽  
pp. 1-11
Author(s):  
Jianfeng Gu ◽  
Yiwu Fang ◽  
Lele Liu ◽  
Xinxin Ma ◽  
Xiaoling Lu

Summary Bursaphelenchus paraleoni n. sp. was isolated from Loblolly pine, Pinus taeda, logs from the USA. The new species is characterised by a lateral field with three lines, 13-16 μm long stylet with small basal swellings, and the excretory pore located slightly posterior to the nerve ring. The male spicules are mitten-shaped, the lamina smoothly tapering towards the distal tip. The condylus is broadly rounded, with a small dorsally bent hook, rostrum triangular or conical with finely rounded tip, and cucullus absent. One midventral precloacal papilla, one adcloacal pair and two postcloacal pairs of genital papillae are present. The bursal flap is long and spade-like with the posterior margin truncate or irregular. Females have a small vulval flap 4-6 μm long, a post-vulval uterine sac extending for 34-49% of the vulva to anus distance, a very long tail with slight ventral curvature, mostly filiform and with a finely rounded terminus, occasionally bluntly rounded. Huge variation in the tails of males and females were observed in a culture. It is similar to species of B. eidmanni, B. leoni, and B. silvestris in the leoni-group but detailed phylogenetic analysis based on 18S, ITS and D2-D3 28S sequences confirmed it as a new species.


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