scholarly journals In Utero and Peripubertal Metals Exposure in Relation to Reproductive Hormones and Sexual Maturation and Progression among Boys in Mexico City

2020 ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  
Keyword(s):  
Sexual Maturation ◽  
Pubic Hair ◽  
In Utero ◽  
Reproductive Hormones ◽  
Testicular Volume ◽  
Metal Exposure ◽  
Reproductive Hormone ◽  
Environmental Toxicants ◽  
Metal Concentrations ◽  
Essential Metal

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.

scholarly journals In utero and peripubertal metals exposure in relation to reproductive hormones and sexual maturation and progression among boys in Mexico City

2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  
Keyword(s):  
Sexual Maturation ◽  
Pubic Hair ◽  
In Utero ◽  
Reproductive Hormones ◽  
Testicular Volume ◽  
Metal Exposure ◽  
Reproductive Hormone ◽  
Environmental Toxicants ◽  
Metal Concentrations ◽  
Essential Metal

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.

scholarly journals In Utero and Peripubertal Metals Exposure in Relation to Reproductive Hormones and Sexual Maturation and Progression among Boys in Mexico City

2020 ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  
Keyword(s):  
Sexual Maturation ◽  
Pubic Hair ◽  
In Utero ◽  
Reproductive Hormones ◽  
Testicular Volume ◽  
Metal Exposure ◽  
Reproductive Hormone ◽  
Essential Metal ◽  
Hormone Levels ◽  
Metal Levels

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.

scholarly journals In Utero and Peripubertal Metals Exposure in Relation to Reproductive Hormones and Sexual Maturation and Progression among Boys in Mexico City

2020 ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  
Keyword(s):  
Sexual Maturation ◽  
Pubic Hair ◽  
In Utero ◽  
Reproductive Hormones ◽  
Testicular Volume ◽  
Metal Exposure ◽  
Reproductive Hormone ◽  
Essential Metal ◽  
Hormone Levels ◽  
Metal Levels

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.

scholarly journals In Utero and Peripubertal Metals Exposure in Relation to Reproductive Hormones and Sexual Maturation and Progression among Boys in Mexico City

2020 ◽  
Author(s):  
Pahriya Ashrap ◽  
John D. Meeker ◽  
Brisa N. Sánchez ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  
Keyword(s):  
Sexual Maturation ◽  
Pubic Hair ◽  
In Utero ◽  
Reproductive Hormones ◽  
Testicular Volume ◽  
Metal Exposure ◽  
Reproductive Hormone ◽  
Essential Metal ◽  
Hormone Levels ◽  
Metal Levels

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.

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
Keyword(s):  
Sexual Maturation ◽  
Statistical Significance ◽  
Reproductive Hormones ◽  
Reproductive Hormone ◽  
Polar Bears ◽  
The Usa ◽  
Males And Females ◽  
Human Care ◽  
Mean Concentration ◽  
Old Females

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.

scholarly journals Impact of phthalate and BPA exposure during in utero windows of susceptibility on reproductive hormones and sexual maturation in peripubertal males

2017 ◽  
Vol 16 (1) ◽  
Author(s):  
Deborah J. Watkins ◽  
Brisa N. Sánchez ◽  
Martha Maria Téllez-Rojo ◽  
Joyce M. Lee ◽  
Adriana Mercado-García ◽  
...  
Keyword(s):  
Sexual Maturation ◽  
In Utero ◽  
Reproductive Hormones ◽  
Windows Of Susceptibility

In Utero and Peripubertal Metals Exposure in Relation to Reproductive Hormones and Sexual Maturation in Girls

2018 ◽  
Vol 2018 (1) ◽  
Author(s):  
Pahriya Ashrap ◽  
Deborah Watkins ◽  
Brisa Sánchez ◽  
Martha María Téllez-Rojo ◽  
Marcela Tamayo y Ortiz ◽  
...  
Keyword(s):  
Sexual Maturation ◽  
In Utero ◽  
Reproductive Hormones ◽  
Metals Exposure

scholarly journals In utero and peripubertal metals exposure in relation to reproductive hormones and sexual maturation and progression among girls in Mexico City

2019 ◽  
Vol 177 ◽  
pp. 108630 ◽  
Author(s):  
Pahriya Ashrap ◽  
Brisa N. Sánchez ◽  
Martha M. Téllez-Rojo ◽  
Niladri Basu ◽  
Marcela Tamayo-Ortiz ◽  
...  
Keyword(s):  
Mexico City ◽  
Sexual Maturation ◽  
In Utero ◽  
Reproductive Hormones ◽  
Metals Exposure

Body phenotypes and sexual maturation in Brazilian and US adolescents: evidence for a change in body mass index Category

2020 ◽  
pp. 1-26
Author(s):  
Jéssica Cumpian Silva ◽  
Ana Elisa Madalena Rinaldi ◽  
Francisco de Assis Guedes Vasconcelos ◽  
Maria Alice Altenburg Assis ◽  
Camila Medeiros Mazzeti ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Body Composition ◽  
Body Mass ◽  
Phase Angle ◽  
Sexual Maturation ◽  
Biochemical Parameters ◽  
Pubertal Development ◽  
The United States ◽  
Pubic Hair ◽  
Cholesterol Ratio

ABSTRACT Objective: Our study aimed to describe body phenotypes (BP) estimated by multivariate analysis and their association with body mass. Design: Body phenotypes were defined based on demographic variables, anthropometric data (body mass, height, skinfolds and circumferences), body composition (phase angle measured by bioelectrical impedance analysis), biochemical parameters (triglycerides, glucose, total cholesterol ratio/Low Density Lipoproteins (LDL), haemoglobin and sexual maturation (pubic hair and breasts or gonads). Analysis of variance (ANOVA) was performed to verify the differences between skin colour and the stages of pubertal development, body phenotypes, body composition, anthropometric, and biochemical variables. Setting: Cities of São Paulo-SP, Piracicaba-SP and Florianópolis-SC from Brazil and the United States. Participants: 9269 adolescents aged between 10 to 15 years old. Results: The composition of BP was similar in all surveys, which are: BP1 was composed by skinfolds, body mass and circumferences variables; BP2 by pubic hair, breast in girls or gonad in boys, height and age; BP3 by cholesterol, triglycerides and glucose; and BP4 by phase angle, haemoglobin and glucose (negative loading). There was a strong correlation (r = 0.9, p <0.001) between BP1 and body mass index. Conclusion: We highlighted independence observed between biochemical parameters, anthropometry, body composition and sexual maturation. BP may support the calculation of scores for diagnosis of obesity based on anthropometric variables and overcome ambiguity in the isolated use of body mass index.

scholarly journals Larger Testes and Higher Inhibin B Levels in Finnish than in Danish Newborn Boys

2006 ◽  
Vol 91 (7) ◽  
pp. 2732-2737 ◽  
Author(s):  
Katharina M. Main ◽  
Jorma Toppari ◽  
Anne-Maarit Suomi ◽  
Marko Kaleva ◽  
Marla Chellakooty ◽  
...  
Keyword(s):  
Sperm Quality ◽  
Genetic Difference ◽  
Reproductive Hormones ◽  
Inhibin B ◽  
Testicular Volume ◽  
Seminiferous Tubules ◽  
Testicular Development ◽  
Testis Size ◽  
University Hospitals ◽  
Prospective Longitudinal

Abstract Context: Recent studies showed that male reproductive health problems, such as cryptorchidism, hypospadias, testicular cancer, and low sperm quality, are more prevalent in Denmark than in Finland. Objectives: We hypothesized that, if fetal testicular dysgenesis contributed to these observations, differences in gonadal development and the hypothalamus-pituitary-testis axis would already be detectable perinatally. Thus, we investigated healthy newborn boys in both countries. Design: This was a prospective, longitudinal population-based study. Setting: Two primary obstetric centers were included at the University Hospitals of Copenhagen, Denmark, and Turku, Finland. Participants: The participants of the study included 633 Danish and 1044 Finnish boys, born at term with appropriate weight for gestational age. Interventions: Ultrasound determination of testis size at 0, 3, and 18 months and blood sampling (n = 727) at 3 months were analyzed. Main Outcome Measures: Testicular volume and reproductive hormones were measured. Results: Testis volume was significantly higher at all ages in Finnish than in Danish boys (medians, 98 vs. 95, 185 vs. 119, and 188 vs. 136 mm3, respectively; P &lt; 0.00001). Testis growth from birth to 3 months was larger in Finnish than in Danish boys (mean, 75 vs. 26 mm3; P &lt; 0.0001). Serum hormone levels were higher in Finnish than Danish boys for inhibin B (median, 456 vs. 385 pg/ml; P &lt; 0.0001), FSH (1.33 vs. 1.21 IU/liter; P &lt; 0.036), and SHBG (143 vs. 136 nmol/liter; P &lt; 0.022). Inhibin B was significantly positively correlated to testicular volume (r = 0.25; P &lt; 0.006). Conclusions: The larger testes and higher inhibin B levels most likely represent a bigger volume of seminiferous tubules in Finnish compared with Danish boys. Although this phenomenon may be attributable to a genetic difference between the two countries, it may also reflect environmental factors influencing testicular development.

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