SHORT COMMUNICATION
Male reproductive hormone profile in Rwandan students J. B. Gahutu Department of Medical Biology, School of Medicine, University of Rwanda, Huye, Rwanda
Keywords Follicle-stimulating hormone—luteinising hormone—Rwanda—testosterone Correspondence Jean Bosco Gahutu, School of Medicine, University of Rwanda, P.O. Box 217 Huye, Rwanda. Tel.: +250 783340040; Fax: +250 252530328; E-mail: [email protected]
Summary To illustrate the male reproductive hormone profile, a study was conducted among healthy male university students living at Butare, Rwanda (altitude: 1 768 m, barometric pressure: 629 mm Hg). Venous blood was collected in the morning, after overnight fasting. Hormonal assays were performed by classical sandwich ELISA technique. Mean values (standard deviation SD) were follicle-stimulating hormone FSH: 3.7 1.6 IU l 1; luteinising hormone LH: 3.6 2.2 IU l 1; and total testosterone: 21.0 7.5 nM. The results compare well with findings of other studies.
Accepted: October 10, 2013 doi: 10.1111/and.12201
Introduction Population-based reference values for reproductive hormones are important in the diagnosis and management of reproductive disorders (Sikaris et al., 2005). The aim of the study was to illustrate the profile of male reproductive hormones in a healthy young male adult population at moderate altitude in Rwanda. Subjects and methods The study was carried out among healthy male students of the University of Rwanda, Huye district (altitude 1768 m, barometric pressure: 629 mmHg), in December 2011. Any disease reported for the preceding 6 months or smoking was exclusion criteria. Most of study participants were nondrinkers, some drank alcohol occasionally. Physical examination was carried out; height and weight were measured on slightly clothed individuals, without shoes. Sampling and sample storage Blood sampling was performed in the morning between 7.00 and 10.00 a.m. after overnight fasting. The subjects were at complete physical rest for at least 10 min before blood sampling. Five milli litre of venous blood was sampled from the cubital vein in a dry tube without anticoagulant. After clotting at room temperature, the 1198
clot was separated from the serum by centrifugation at 700 g during 10 min, after which the serum was immediately transferred in a dry tube, stored in the freezer at 20 °C and analysed within 1 month. Hormonal assays Samples were defrozen at ambient temperature and homogenised before hormonal assays. Total testosterone, FSH and LH hormonal assays were performed in the laboratory of Butare University Teaching Hospital by classical sandwich ELISA technique, using a Dynex MRX ELISA reader machine and reagent kits from Human Diagnostics (Wiesbaden, Germany). Laboratory procedures, calibration and internal quality control were as per instructions from the manufacturer. Statistical analysis The statistical analysis was performed with the Excel 2007 software for the determination of the mean, the standard deviation and the 2.5th–97.5th percentile interval. Ethical approval The research project was approved by the Ethics Committee of the School of Medicine of the University of Rwanda. Informed consent was obtained from the study participants before sampling. © 2013 Blackwell Verlag GmbH Andrologia 2014, 46, 1198–1199
J. B. Gahutu
Male reproductive hormone profile Rwanda
Table 1 Hormone profile for male reproductive function
Parameter
n
Unit
Mean SD
FSH LH Testosterone
61 61 98
IU l 1 IU l 1 ng ml nM
3.7 3.6 6.1 21.0
1
1.6 2.2 2.1 7.5
2.5th–97.5th percentile interval 1.3–6.9 0.5–9.1 2.5–10.4 8.7–36.1
SD, standard deviation; FSH, follicle-stimulating hormone; LH, luteinising hormone.
Results In total, 104 subjects participated in the study. All samples were tested for testosterone and six outliers removed. 61 samples were tested for FSH and LH. The age (mean SD) was 22 2 (range: 20–28) years. The weight was 62.5 6.7 (range: 51–79) kg. The body mass index was 21.2 2.1 (range: 15.7–29.3) kg m ². Mean values and 2.5th–97.5th percentile intervals for FSH, LH and total testosterone are shown in Table 1. Discussion All recruited subjects were nonobese (BMI < 30 kg m ²), which excludes any effect of obesity on reproductive hormone concentration (Sikaris et al., 2005). Considering that testosterone concentration declines with age (Friedrich et al., 2008), the values from this study are only applicable to young adult men. The sampling was performed between 7.00 and 10.00 a.m. As testosterone secretion shows a circadian rhythm (Diver, 2006), the secretion being maximal early in the morning and decreasing during the day, variations with findings from other studies may be related to the sampling hour. Variations of testosterone levels have been reported to be correlated with abnormalities in metabolic markers (Haren et al., 2008). The young age and normal nutritional status of participants in our study justify normal results for testosterone, FSH and LH. Our results compare well with the findings of other studies for FSH and LH (Dighe et al., 2005; Sikaris et al., 2005), and testosterone (Sikaris et al., 2005; Friedrich et al., 2008; Bhasin et al., 2011). At the moderate altitude of the study site, there is no hypoxaemia and haemoglobin
© 2013 Blackwell Verlag GmbH Andrologia 2014, 46, 1198–1199
concentration is normal (Gahutu et al., 2005). There is no increase in testosterone as an adaptation to altitude. Acknowledgements We are grateful to the study participants for their cooperation, the laboratory technicians for their technical skills and the Research Commission of the University of Rwanda for its financial support in cooperation with the Swedish International Development Agency. References Bhasin S, Pencina M, Jasuja GK, Travison TG, Coviello A, Orwoll E, Wang PY, Nielson C, Wu F, Tajar A, Labrie F, Vesper H, Zhang A, Ulloor J, Singh R, D’Agostino R, Vasan RS (2011) Reference ranges for testosterone in men generated using liquid chromatography tandem mass spectrometry in a community-based sample of healthy nonobese young men in the Framingham Heart Study and applied to three geographically distinct cohorts. J Clin Endocrinol Metab 96:2430–2439. Dighe AS, Moy JM, Hayes FJ, Sluss PM (2005) Highresolution reference ranges for estradiol, luteinizing hormone, and follicle-stimulating hormone in men and women using the AxSYM assay system. Clin Biochem 38:175–179. Diver MJ (2006) Analytical and physiological factors affecting the interpretation of serum testosterone concentration in men. Ann Clin Biochem 43:3–12. Friedrich N, V€ olzke H, Rosskopf D, Steveling A, Krebs A, Nauck M, Wallaschofski H (2008) Reference ranges for serum dehydroepiandrosterone sulfate and testosterone in adult men. J Androl 29:610–617. Gahutu JB, Wane J, Uwambazimana JA, Midonzi D, Twagirumugabe T, Ndoli Minega J, Leybaert L (2005) A Rwandan altitude blood gas, acid-base and hemoglobin study. Clin Chim Acta 357:86–87. Haren MT, Banks WA, Perry HM III, Patrick P, Malmstrom TK, Miller DK, Morley JE (2008) Predictors of serum testosterone and DHEAS in African-American Men. Int J Androl 31:50–59. Sikaris K, McLachlan RI, Kazlauskas R, de Kretser D, Holden CA, Handelsman DJ (2005) Reproductive hormone reference intervals for healthy fertile young men: evaluation of automated platform assays. J Clin Endocrinol Metab 90:5928–5936.
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Copyright of Andrologia is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
Male reproductive hormone profile in Rwandan students J. B. Gahutu Department of Medical Biology, School of Medicine, University of Rwanda, Huye, Rwanda
Keywords Follicle-stimulating hormone—luteinising hormone—Rwanda—testosterone Correspondence Jean Bosco Gahutu, School of Medicine, University of Rwanda, P.O. Box 217 Huye, Rwanda. Tel.: +250 783340040; Fax: +250 252530328; E-mail: [email protected]
Summary To illustrate the male reproductive hormone profile, a study was conducted among healthy male university students living at Butare, Rwanda (altitude: 1 768 m, barometric pressure: 629 mm Hg). Venous blood was collected in the morning, after overnight fasting. Hormonal assays were performed by classical sandwich ELISA technique. Mean values (standard deviation SD) were follicle-stimulating hormone FSH: 3.7 1.6 IU l 1; luteinising hormone LH: 3.6 2.2 IU l 1; and total testosterone: 21.0 7.5 nM. The results compare well with findings of other studies.
Accepted: October 10, 2013 doi: 10.1111/and.12201
Introduction Population-based reference values for reproductive hormones are important in the diagnosis and management of reproductive disorders (Sikaris et al., 2005). The aim of the study was to illustrate the profile of male reproductive hormones in a healthy young male adult population at moderate altitude in Rwanda. Subjects and methods The study was carried out among healthy male students of the University of Rwanda, Huye district (altitude 1768 m, barometric pressure: 629 mmHg), in December 2011. Any disease reported for the preceding 6 months or smoking was exclusion criteria. Most of study participants were nondrinkers, some drank alcohol occasionally. Physical examination was carried out; height and weight were measured on slightly clothed individuals, without shoes. Sampling and sample storage Blood sampling was performed in the morning between 7.00 and 10.00 a.m. after overnight fasting. The subjects were at complete physical rest for at least 10 min before blood sampling. Five milli litre of venous blood was sampled from the cubital vein in a dry tube without anticoagulant. After clotting at room temperature, the 1198
clot was separated from the serum by centrifugation at 700 g during 10 min, after which the serum was immediately transferred in a dry tube, stored in the freezer at 20 °C and analysed within 1 month. Hormonal assays Samples were defrozen at ambient temperature and homogenised before hormonal assays. Total testosterone, FSH and LH hormonal assays were performed in the laboratory of Butare University Teaching Hospital by classical sandwich ELISA technique, using a Dynex MRX ELISA reader machine and reagent kits from Human Diagnostics (Wiesbaden, Germany). Laboratory procedures, calibration and internal quality control were as per instructions from the manufacturer. Statistical analysis The statistical analysis was performed with the Excel 2007 software for the determination of the mean, the standard deviation and the 2.5th–97.5th percentile interval. Ethical approval The research project was approved by the Ethics Committee of the School of Medicine of the University of Rwanda. Informed consent was obtained from the study participants before sampling. © 2013 Blackwell Verlag GmbH Andrologia 2014, 46, 1198–1199
J. B. Gahutu
Male reproductive hormone profile Rwanda
Table 1 Hormone profile for male reproductive function
Parameter
n
Unit
Mean SD
FSH LH Testosterone
61 61 98
IU l 1 IU l 1 ng ml nM
3.7 3.6 6.1 21.0
1
1.6 2.2 2.1 7.5
2.5th–97.5th percentile interval 1.3–6.9 0.5–9.1 2.5–10.4 8.7–36.1
SD, standard deviation; FSH, follicle-stimulating hormone; LH, luteinising hormone.
Results In total, 104 subjects participated in the study. All samples were tested for testosterone and six outliers removed. 61 samples were tested for FSH and LH. The age (mean SD) was 22 2 (range: 20–28) years. The weight was 62.5 6.7 (range: 51–79) kg. The body mass index was 21.2 2.1 (range: 15.7–29.3) kg m ². Mean values and 2.5th–97.5th percentile intervals for FSH, LH and total testosterone are shown in Table 1. Discussion All recruited subjects were nonobese (BMI < 30 kg m ²), which excludes any effect of obesity on reproductive hormone concentration (Sikaris et al., 2005). Considering that testosterone concentration declines with age (Friedrich et al., 2008), the values from this study are only applicable to young adult men. The sampling was performed between 7.00 and 10.00 a.m. As testosterone secretion shows a circadian rhythm (Diver, 2006), the secretion being maximal early in the morning and decreasing during the day, variations with findings from other studies may be related to the sampling hour. Variations of testosterone levels have been reported to be correlated with abnormalities in metabolic markers (Haren et al., 2008). The young age and normal nutritional status of participants in our study justify normal results for testosterone, FSH and LH. Our results compare well with the findings of other studies for FSH and LH (Dighe et al., 2005; Sikaris et al., 2005), and testosterone (Sikaris et al., 2005; Friedrich et al., 2008; Bhasin et al., 2011). At the moderate altitude of the study site, there is no hypoxaemia and haemoglobin
© 2013 Blackwell Verlag GmbH Andrologia 2014, 46, 1198–1199
concentration is normal (Gahutu et al., 2005). There is no increase in testosterone as an adaptation to altitude. Acknowledgements We are grateful to the study participants for their cooperation, the laboratory technicians for their technical skills and the Research Commission of the University of Rwanda for its financial support in cooperation with the Swedish International Development Agency. References Bhasin S, Pencina M, Jasuja GK, Travison TG, Coviello A, Orwoll E, Wang PY, Nielson C, Wu F, Tajar A, Labrie F, Vesper H, Zhang A, Ulloor J, Singh R, D’Agostino R, Vasan RS (2011) Reference ranges for testosterone in men generated using liquid chromatography tandem mass spectrometry in a community-based sample of healthy nonobese young men in the Framingham Heart Study and applied to three geographically distinct cohorts. J Clin Endocrinol Metab 96:2430–2439. Dighe AS, Moy JM, Hayes FJ, Sluss PM (2005) Highresolution reference ranges for estradiol, luteinizing hormone, and follicle-stimulating hormone in men and women using the AxSYM assay system. Clin Biochem 38:175–179. Diver MJ (2006) Analytical and physiological factors affecting the interpretation of serum testosterone concentration in men. Ann Clin Biochem 43:3–12. Friedrich N, V€ olzke H, Rosskopf D, Steveling A, Krebs A, Nauck M, Wallaschofski H (2008) Reference ranges for serum dehydroepiandrosterone sulfate and testosterone in adult men. J Androl 29:610–617. Gahutu JB, Wane J, Uwambazimana JA, Midonzi D, Twagirumugabe T, Ndoli Minega J, Leybaert L (2005) A Rwandan altitude blood gas, acid-base and hemoglobin study. Clin Chim Acta 357:86–87. Haren MT, Banks WA, Perry HM III, Patrick P, Malmstrom TK, Miller DK, Morley JE (2008) Predictors of serum testosterone and DHEAS in African-American Men. Int J Androl 31:50–59. Sikaris K, McLachlan RI, Kazlauskas R, de Kretser D, Holden CA, Handelsman DJ (2005) Reproductive hormone reference intervals for healthy fertile young men: evaluation of automated platform assays. J Clin Endocrinol Metab 90:5928–5936.
1199
Copyright of Andrologia is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.
