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Shi H, Korejo NA, Kamboh AA, Korejo RA, Shi F. Effects of hyperthyroidism and diabetes mellitus on spermatogenesis in peri- and post-pubertal mice. Front Endocrinol (Lausanne) 2023; 14:1191571. [PMID: 37654561 PMCID: PMC10465343 DOI: 10.3389/fendo.2023.1191571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 07/24/2023] [Indexed: 09/02/2023] Open
Abstract
Introduction Diabetes and thyroid dysfunction often co-exist. One autoimmune disorder always invites another and it has been reported that such co-morbid ailments always become detrimental to the health of the patients. Materials and methods In our previous work, we elucidated the interactions of diabetes and hypothyroidism on testicular development and spermatogenesis. However, the present study illuminates the interface between diabetes and hyperthyroidism, where 16 ICR pregnant primiparous mice were used and subsequently 48 male pups were randomly selected (n=12/group) and separated into 4 groups: control (C), diabetic (D), diabetic + hyperthyroidism (DH) and hyperthyroidism (H). Results Computerized sperm analyses showed significant reductions in count by 20% and increases of 15% in D and H animals, respectively, vs. controls. However, rapid progressive sperm motility was significantly lower only in D (30%) compared with C mice. Our histomorphometric investigation depicted damaging effects on testicular and epididymal tissues; the stroma adjacent to the seminiferous tubules of the D mice revealed edematous fluid and unstructured material. However, in the epididymis, germ cell diminution contraction of tubules, compacted principal and clear cells, lipid vacuolization, atypical cellular connections, exfoliated epithelial cells, and round spermatids were conspicuous in DH mice. Discussion Collectively, our experiment was undertaken to ultimately better recognize male reproductive disorders in diabetic-hyperthyroid patients.
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Affiliation(s)
- Hanhao Shi
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
- College of Animal Science and Technology, Anhui Agricultural University, Hefei, China
| | - Nazar Ali Korejo
- Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University Tandojam, Hyderabad, Pakistan
| | - Asghar Ali Kamboh
- Faculty of Animal Husbandry and Veterinary Sciences, Sindh Agriculture University Tandojam, Hyderabad, Pakistan
| | - Rashid Ali Korejo
- Department of Animal Nutrition, Faculty of Animal Production and Technology, Shaheed Benazir Bhutto University of Veterinary and Animal Sciences, Sakrand, Pakistan
| | - Fangxiong Shi
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China
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Mazzilli R, Medenica S, Di Tommaso AM, Fabozzi G, Zamponi V, Cimadomo D, Rienzi L, Ubaldi FM, Watanabe M, Faggiano A, La Vignera S, Defeudis G. The role of thyroid function in female and male infertility: a narrative review. J Endocrinol Invest 2023; 46:15-26. [PMID: 35945393 PMCID: PMC9829629 DOI: 10.1007/s40618-022-01883-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 07/25/2022] [Indexed: 01/13/2023]
Abstract
PURPOSE We herein aimed to review the new insights into the impact of impaired thyroid function on male and female fertility, spacing from spontaneous pregnancy to ART, with the objective of providing an updated narrative revision of the literature. METHODS This narrative review was performed for all available prospective, retrospective and review articles, published up to 2021 in PubMed. Data were extracted from the text and from the tables of the manuscript. RESULTS Thyroid dysfunction is frequently associated with female infertility, whereas its link with male infertility is debated. Female wise, impaired function is detrimental to obstetric and fetal outcomes both in spontaneous pregnancies and in those achieved thanks to assisted reproduction technologies (ART). Furthermore, the reference range of TSH in natural pregnancy and ART procedures has recently become a matter of debate following recent reports in this field. On the other hand, the impact of thyroid function on the male reproductive system is less clear, although a possible role is suggested via modulation of Sertoli and Leydig cells function and spermatogenesis. CONCLUSION Thyroid function should be carefully monitored in both male and female, in couples seeking spontaneous pregnancy as well as ART, as treatment is generally immediate and likely to improve chances of success.
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Affiliation(s)
- R Mazzilli
- Endocrinology Unit, Department of Clinical and Molecular Medicine, Sapienza University of Rome, Sant' Andrea Hospital, Rome, Italy
| | - S Medenica
- Department of Endocrinology, Internal Medicine Clinic, Clinical Center of Montenegro, School of Medicine, University of Montenegro, Podgorica, Montenegro
| | - A M Di Tommaso
- Unit of Endocrinology and Diabetes, Department of Medicine, University Campus Bio-Medico di Roma, Rome, Italy
| | - G Fabozzi
- Clinica Valle Giulia, GeneraLife IVF, Rome, Italy
| | - V Zamponi
- Endocrinology Unit, Department of Clinical and Molecular Medicine, Sapienza University of Rome, Sant' Andrea Hospital, Rome, Italy
| | - D Cimadomo
- Clinica Valle Giulia, GeneraLife IVF, Rome, Italy
| | - L Rienzi
- Clinica Valle Giulia, GeneraLife IVF, Rome, Italy
| | - F M Ubaldi
- Clinica Valle Giulia, GeneraLife IVF, Rome, Italy
| | - M Watanabe
- Department of Experimental Medicine, Sapienza University of Rome, Viale Regina Elena, 328, 00161, Rome, Italy.
| | - A Faggiano
- Endocrinology Unit, Department of Clinical and Molecular Medicine, Sapienza University of Rome, Sant' Andrea Hospital, Rome, Italy
| | - S La Vignera
- Department of Clinical and Experimental Medicine, Policlinico "G. Rodolico, " University of Catania, Catania, Italy
| | - G Defeudis
- Unit of Endocrinology and Diabetes, Department of Medicine, University Campus Bio-Medico di Roma, Rome, Italy
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Jasuja R, Pencina KM, Spencer DJ, Peng L, Privat F, Dhillo W, Jayasena C, Hayes F, Yeap BB, Matsumoto AM, Bhasin S. Reference intervals for free testosterone in adult men measured using a standardized equilibrium dialysis procedure. Andrology 2023; 11:125-133. [PMID: 36251328 DOI: 10.1111/andr.13310] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/12/2022] [Accepted: 09/26/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Free testosterone (FT) determination may be helpful in evaluating men suspected of testosterone deficiency especially in conditions with altered binding-protein concentrations. However, methods for measuring FT by equilibrium dialysis and reference intervals vary among laboratories. OBJECTIVE To determine reference intervals for FT in healthy, nonobese men by age groups as well as in healthy young men, 19-39 years, using a standardized equilibrium dialysis procedure METHODS: We measured FT in 145 healthy, nonobese men, 19 years or older, using a standardized equilibrium dialysis method performed for 16-h at 37°C using undiluted serum and dialysis buffer that mimicked the ionic composition of human plasma. FT in dialysate was measured using a CDC-certified liquid chromatography tandem mass spectrometry assay. RESULTS In healthy nonobese men, the 2.5th, 10th, 50th, 90th, and 97.5th percentile values for FT were 66, 91, 141, 240, and 309 pg/ml, respectively; corresponding values for men, 19-39 years, were 120, 128, 190, 274, and 368 pg/ml, respectively. FT levels by age groups exhibit the expected age-related decline. FT levels were negatively associated with body mass index, age, and sex hormone-binding globulin (SHBG) levels. Percent FT was lower in middle-aged and older men than young men adjusting for SHBG level. DISCUSSION Further studies are needed to determine how these reference intervals apply to the diagnosis of androgen deficiency in clinical populations and in men of different races and ethnicities in different geographic regions. CONCLUSION Reference intervals for free FT levels (normative range 66-309 pg/ml [229-1072 pmol/L] in all men and 120-368 pg/ml [415-1274 pmol/L] in men, 19-39 years), measured using a standardized equilibrium dialysis method in healthy nonobese men, provide a rational basis for categorizing FT levels. These intervals require further validation in other populations, in relation to outcomes, and in randomized trials.
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Affiliation(s)
- Ravi Jasuja
- Research Program in Men's Health: Aging and Metabolism; Boston Claude D. Pepper Older Americans Independence Center; Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Karol M Pencina
- Research Program in Men's Health: Aging and Metabolism; Boston Claude D. Pepper Older Americans Independence Center; Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Daniel J Spencer
- Research Program in Men's Health: Aging and Metabolism; Boston Claude D. Pepper Older Americans Independence Center; Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Liming Peng
- Research Program in Men's Health: Aging and Metabolism; Boston Claude D. Pepper Older Americans Independence Center; Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Fabiola Privat
- Research Program in Men's Health: Aging and Metabolism; Boston Claude D. Pepper Older Americans Independence Center; Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Waljit Dhillo
- Division of Diabetes, Endocrinology and Metabolism, Imperial College London Faculty of Medicine, Hammersmith Hospital, London, UK
| | - Channa Jayasena
- Section of Investigative Medicine, Imperial College London Faculty of Medicine, Hammersmith Hospital, London, UK
| | - Frances Hayes
- Division of Endocrinology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Bu B Yeap
- Medical School, University of Western Australia; Department of Endocrinology and Diabetes, Fiona Stanley Hospital, Perth, Western Australia, Australia
| | - Alvin M Matsumoto
- Geriatric Research, Education and Clinical Center, VA Puget Sound Health Care System and Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, Washington, USA
| | - Shalender Bhasin
- Research Program in Men's Health: Aging and Metabolism; Boston Claude D. Pepper Older Americans Independence Center; Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Abstract
Thyroid hormones are primarily responsible for regulating the basal metabolic rate but also make important contributions to reproductive function and fetal development. Both hyper- and hypothyroidism in pregnancy have been associated with increased risks of complications that include preeclampsia and low birth weight, among others. Furthermore, thyroid hormone deficiency in the developing fetus results in neurodevelopmental delay. As the fetus is exclusively reliant on maternal thyroid hormone for most of the first trimester and requires continued maternal supply until birth, identifying maternal thyroid dysfunction is critically important. However, evaluating thyroid function in pregnancy is challenging because of the many physiological changes that affect concentrations of thyroid-related analytes. Increasing plasma human chorionic gonadotropin (hCG) concentrations in the second half of the first trimester elicit a corresponding transient decrease in thyroid-stimulating hormone (TSH), and continually increasing estradiol concentrations throughout pregnancy cause substantial increases in thyroxine-binding globulin (TBG) and total thyroxine (T4) relative to the nonpregnant state. Lastly, free T4 concentrations gradually decrease with increasing gestational age. For these reasons, it is essential to interpret thyroid function test results in the context of trimester-specific reference intervals to avoid misclassification of thyroid status. This review summarizes the effects of thyroid dysfunction prior to conception and during pregnancy and describes considerations for the laboratory assessment of thyroid function in pregnant women.
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Affiliation(s)
- K Aaron Geno
- Department of Pathology, Texas Tech University Health Sciences Center, El Paso, TX, USA
| | - Robert D Nerenz
- Department of Pathology and Laboratory Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH, USA.,Geisel School of Medicine, Dartmouth College, Hanover, NH, USA
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Ren B, Zhu Y. A New Perspective on Thyroid Hormones: Crosstalk with Reproductive Hormones in Females. Int J Mol Sci 2022; 23:ijms23052708. [PMID: 35269847 PMCID: PMC8911152 DOI: 10.3390/ijms23052708] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/25/2022] [Accepted: 02/21/2022] [Indexed: 12/19/2022] Open
Abstract
Accumulating evidence has shown that thyroid hormones (THs) are vital for female reproductive system homeostasis. THs regulate the reproductive functions through thyroid hormone receptors (THRs)-mediated genomic- and integrin-receptor-associated nongenomic mechanisms, depending on TH ligand status and DNA level, as well as transcription and extra-nuclear signaling transduction activities. These processes involve the binding of THs to intracellular THRs and steroid hormone receptors or membrane receptors and the recruitment of hormone-response elements. In addition, THs and other reproductive hormones can activate common signaling pathways due to their structural similarity and shared DNA consensus sequences among thyroid, peptide, and protein hormones and their receptors, thus constituting a complex and reciprocal interaction network. Moreover, THs not only indirectly affect the synthesis, secretion, and action of reproductive hormones, but are also regulated by these hormones at the same time. This crosstalk may be one of the pivotal factors regulating female reproductive behavior and hormone-related diseases, including tumors. Elucidating the interaction mechanism among the aforementioned hormones will contribute to apprehending the etiology of female reproductive diseases, shedding new light on the treatment of gynecological disorders.
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Affiliation(s)
- Bingtao Ren
- School of Pharmacy, Fudan University, Shanghai 200032, China;
| | - Yan Zhu
- Laboratory of Reproductive Pharmacology, NHC Key Laboratory of Reproduction Regulation, Shanghai Institute for Biomedical and Pharmaceutical Technologies, Fudan University, Shanghai 200032, China
- Correspondence: ; Tel.: +86-21-64438416
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Endocrinopathies and Male Infertility. LIFE (BASEL, SWITZERLAND) 2021; 12:life12010010. [PMID: 35054403 PMCID: PMC8779600 DOI: 10.3390/life12010010] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/09/2021] [Accepted: 12/16/2021] [Indexed: 01/22/2023]
Abstract
Male infertility is approaching a concerning prevalence worldwide, and inflicts various impacts on the affected couple. The hormonal assessment is a vital component of male fertility evaluation as endocrine disorders are markedly reversible causatives of male infertility. Precise hormonal regulations are prerequisites to maintain normal male fertility parameters. The core male reproductive event, spermatogenesis, entails adequate testosterone concentration, which is produced via steroidogenesis in the Leydig cells. Physiological levels of both the gonadotropins are needed to achieve normal testicular functions. The hypothalamus-derived gonadotropin-releasing hormone (GnRH) is considered the supreme inducer of the gonadotropins and thereby the subsequent endocrine reproductive events. This hypothalamic–pituitary–gonadal (HPG) axis may be modulated by the thyroidal or adrenal axis and numerous other reproductive and nonreproductive hormones. Disruption of this fine hormonal balance and their crosstalk leads to a spectrum of endocrinopathies, inducing subfertility or infertility in men. This review article will discuss the most essential endocrinopathies associated with male factor infertility to aid precise understanding of the endocrine disruptions-mediated male infertility to encourage further research to reveal the detailed etiology of male infertility and perhaps to develop more customized therapies for endocrinopathy-induced male infertility.
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Ramadan HM, Taha NA, Ahmed HH. Melatonin enhances antioxidant defenses but could not ameliorate the reproductive disorders in induced hyperthyroidism model in male rats. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:4790-4804. [PMID: 32951169 DOI: 10.1007/s11356-020-10682-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 08/30/2020] [Indexed: 06/11/2023]
Abstract
The present study was carried out to clarify the effect of different doses of melatonin on some reproductive hormones, serum total antioxidant, histopathological examination, lipid peroxidation, and antioxidant parameters in liver, kidney, heart, and testis tissues in induced-hyperthyroidism (HT) male rat model. A total of 75 mature male Wistar rats were equally allocated into five groups; control groups were daily I/P injected with distilled water containing 4 M ammonium hydroxide in methanol and 1% absolute ethanol; on hyperthyroidism model group, rats received daily I/P injection of L-thyroxine (0.2 mg/kg body weight). In melatonin-treated groups, rats were injected with the same dose of L-thyroxine followed by I/P injection of melatonin (1, 5, or 10 mg/kg, respectively) for 21 days. The hyperthyroidism group showed significant increase in serum thyroxine (T4), triiodothyronine (T3), and testosterone levels and a significant decrease in the levels of thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), luteinizing hormone (LH), and serum total antioxidants capacity, with a significant decrease in superoxide dismutase (SOD) activity and glutathione reductase (GSH) content with a significant increase in malondialdehyde (MDA) concentration in all examined tissues. While, melatonin co-treatment to HT groups partially counteracted the effect of hyperthyroidism by decreasing serum T4 and T3 levels and increasing serum TSH. In addition, melatonin could decrease serum levels of FSH, LH, and testosterone, as well as it could increase serum total antioxidants capacity, SOD activity, and GSH content and decreased MDA concentration in all examined tissues. Additionally, melatonin could amend the histopathological alterations in the examined tissues of hyperthyroid rats but not the testicular tissue. It is concluded that melatonin has a protective role against the hyperthyroidism-induced oxidative damage but cannot ameliorate the reproductive disorders in male rat model.
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Affiliation(s)
- Hager M Ramadan
- Department of Physiology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt.
| | - Nadia A Taha
- Department of Physiology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
| | - Hodallah H Ahmed
- Department of Physiology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt
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Association Between Overt Hyperthyroidism and Risk of Sexual Dysfunction in Both Sexes: A Systematic Review and Meta-Analysis. J Sex Med 2020; 17:2198-2207. [PMID: 32800738 DOI: 10.1016/j.jsxm.2020.07.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 07/04/2020] [Accepted: 07/17/2020] [Indexed: 11/24/2022]
Abstract
BACKGROUND Numerous studies have shown the detrimental effects of overt hyperthyroidism on sexual functioning but a quantitative result has not yet been synthesized. AIM To conduct a systematic review and meta-analysis that quantifies the association between overt hyperthyroidism and the risk of sexual dysfunction (SD). METHODS A meta-analysis of studies in the literature published prior to February 1, 2020, from 4 electronic databases (MEDLINE, Embase, Cochrane Library databases, and PsychINFO) was conducted. All analyses were performed using the random-effects model comparing individuals with and without overt hyperthyroidism. OUTCOMES The strength of the association between overt hyperthyroidism and risk of SD was quantified by calculating the relative risk (RR) and the standard mean difierences with 95% CI. The quality of evidence for the reported outcome was based on the Grading of Recommendations Assessment, Development, and Evaluation approach. RESULTS Of 571 publications, a total of 7 studies involving 323,257 individuals were included. Synthetic results from 7 eligible studies indicated that overt hyperthyroidism led to significant SD in both sexes (pooled RR = 2.59, 95% CI: 1.3-5.17, P = .007; heterogeneity: I2 = 98.8%, P < .001). When we analyzed the data of men and women independently, the pooled results consistently showed that men and women with overt hyperthyroidism were at over 2-fold higher risk of SD than the general populations (RR for males = 2.59, 95% CI: 1.03-6.52, P = .044; RR for females = 2.51, 95% CI: 1.47-4.28, P = .001). Combined standard mean diffierences from those studies providing the Female Sexual Function Index (FSFI) suggested that women with overt hyperthyroidism were associated with a significantly lower FSFI value in FSFI total scores, subscale sexual arousal, lubrication, orgasm, and satisfaction domain (all P < .05). The overall quality of evidence in our study was considered to be moderate. CLINICAL IMPLICATIONS Clinicians should know the detrimental effects of overt hyperthyroidism on sexual functioning in clinical practice. Measurement of thyroid hormones should be included in the assessment of patients presenting with SD when they show symptoms of clinical hyperthyroidism. STRENGTHS & LIMITATIONS This is the first meta-analysis quantifying the relationship between overt hyperthyroidism and the risks of SD. However, the combined results were derived from limited retrospective studies along with substantial heterogeneities. CONCLUSION Our study has confirmed the potentially devastating sexual health consequences caused by overt hyperthyroidism. However, additional rigorous studies with sizable samples are still needed to better elucidate this evidence. Pan Y, Xie Q, Zhang Z, et al. Association Between Overt Hyperthyroidism and Risk of Sexual Dysfunction in Both Sexes: A Systematic Review and Meta-Analysis. J Sex Med 2020;17:2198-2207.
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Krassas GE, Markou KB. The impact of thyroid diseases starting from birth on reproductive function. Hormones (Athens) 2019; 18:365-381. [PMID: 31734887 DOI: 10.1007/s42000-019-00156-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 10/30/2019] [Indexed: 12/19/2022]
Abstract
The aim of this review is to provide relevant information regarding the impact of thyroid disease, starting from birth and mainly concerning hyperthyroidism and hypothyroidism, on reproduction. Hyperthyroidism occurs much less commonly in children than hypothyroidism, with Graves' disease (GD) being the most common cause of thyrotoxicosis in children. Children born with neonatal GD have no defects in the reproductive system that could be related to hyperthyroidism. Current treatment options include antithyroid drugs (ATD), surgery, and radioactive iodine (RAI). In males, normal thyroid function seems important, at least in some parameters, for maintenance of semen quality via genomic or non-genomic mechanisms, either by locally acting on Sertoli cells, Leydig cells, or germ cells, or by affecting crosstalk between the HPT axis and the HPG axis. Sexual behavior may also be affected in thyroxic men, although many of these patients may have normal free testosterone levels. In women, menstrual irregularities are the most common reproduction-related symptoms in thyrotoxicosis, while this disorder is also associated with reduced fertility, although most women remain ovulatory. An increase in sex hormone-binding globulin (SHBG) and androgens, thyroid autoimmunity, and an impact on uterine oxidative stress are the main pathophysiological mechanisms which may influence female fertility. Thyroid hormones are responsible for normal growth and development during pre- and postnatal life, congenital hypothyroidism (CH) being the most common cause of neonatal thyroid disorders, affecting about one newborn infant in 3500. The reproductive tract appears to develop normally in cretins. Today, CH-screening programs allow for early identification and treatment, and, as a result, affected children now achieve normal or near-normal development. Hypothyroidism in males is associated with decreased libido or impotence. Although little is currently known about the effects of hypothyroidism on spermatogenesis and fertility, it has been established that sperm morphology and motility are mainly affected. In women of reproductive age, hypothyroidism results in changes in cycle length and amount of bleeding. Moreover, a negative effect on fertility and higher miscarriage rates has also been described.
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Affiliation(s)
- Gerasimos E Krassas
- IASEIO Medical Center, Tz. Kennendy 115B, Pylea, 55535, Thessaloniki, Greece.
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10
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De Vincentis S, Monzani ML, Brigante G. Crosstalk between gonadotropins and thyroid axis. ACTA ACUST UNITED AC 2018; 70:609-620. [PMID: 29999286 DOI: 10.23736/s0026-4784.18.04271-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Gonadotropins and thyroid hormones are essential, respectively, for reproduction and metabolism. The classical endocrinological approach is based on the detection of axes that start from the hypothalamus and arrive at the final effector organ, in this case gonads and thyroid. However, several clues suggest that these axes do not work in parallel, but they dialogue with each other. In this article, we review evidences demonstrating crosstalk between gonadotropins and thyroid axis. Firstly, there is an undeniable structural similarity of both hormones and receptors, maybe due to a common ancient origin. This structural similarity leads to possible interaction at the receptor level, explaining the influence of thyroid stimulating hormone on gonadal development and vice versa. Indeed, altered levels of thyroid hormones could lead to different disorders of gonadal development and function throughout entire life, especially during puberty and fertile life. We here report the current knowledge on this item both in males and in females. In particular, we deepen the interaction between thyroid and gonads in two situations in females: polycystic ovary syndrome, the most frequent cause of menstrual alteration, and pregnancy.
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Affiliation(s)
- Sara De Vincentis
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy.,Department of Medical Specialties, Azienda Ospedaliero-Universitaria of Modena, OCSAE, Modena, Italy
| | - Maria L Monzani
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy.,Department of Medical Specialties, Azienda Ospedaliero-Universitaria of Modena, OCSAE, Modena, Italy
| | - Giulia Brigante
- Unit of Endocrinology, Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio Emilia, Modena, Italy - .,Department of Medical Specialties, Azienda Ospedaliero-Universitaria of Modena, OCSAE, Modena, Italy
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Corona G, Wu FCW, Forti G, Lee DM, O'Connor DB, O'Neill TW, Pendleton N, Bartfai G, Boonen S, Casanueva FF, Finn JD, Giwercman A, Han TS, Huhtaniemi IT, Kula K, Lean MEJ, Punab M, Vanderschueren D, Jannini EA, Mannucci E, Maggi M. Thyroid hormones and male sexual function. ACTA ACUST UNITED AC 2012; 35:668-79. [PMID: 22834774 DOI: 10.1111/j.1365-2605.2012.01266.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The role of thyroid hormones in the control of erectile functioning has been only superficially investigated. The aim of the present study was to investigate the association between thyroid and erectile function in two different cohorts of subjects. The first one derives from the European Male Ageing Study (EMAS study), a multicentre survey performed on a sample of 3369 community-dwelling men aged 40-79 years (mean 60 ± 11 years). The second cohort is a consecutive series of 3203 heterosexual male patients (mean age 51.8 ± 13.0 years) attending our Andrology and Sexual Medicine Outpatient Clinic for sexual dysfunction at the University of Florence (UNIFI study). In the EMAS study all subjects were tested for thyroid-stimulating hormone (TSH) and free thyroxine (FT4). Similarly, TSH levels were checked in all patients in the UNIFI study, while FT4 only when TSH resulted outside the reference range. Overt primary hyperthyroidism (reduced TSH and elevated FT4, according to the reference range) was found in 0.3 and 0.2% of EMAS and UNIFI study respectively. In both study cohorts, suppressed TSH levels were associated with erectile dysfunction (ED). Overt hyperthyroidism was associated with an increased risk of severe erectile dysfunction (ED, hazard ratio = 14 and 16 in the EMAS and UNIFI study, respectively; both p < 0.05), after adjusting for confounding factors. These associations were confirmed in nested case-control analyses, comparing subjects with overt hyperthyroidism to age, BMI, smoking status and testosterone-matched controls. Conversely, no association between primary hypothyroidism and ED was observed. In conclusion, erectile function should be evaluated in all individuals with hyperthyroidism. Conversely, assessment of thyroid function cannot be recommended as routine practice in all ED patients.
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Affiliation(s)
- G Corona
- Department of Clinical Physiopathology, Sexual Medicine and Andrology Unit, University of Florence, Florence, Italy
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Maggi M, Buvat J, Corona G, Guay A, Torres LO. Hormonal causes of male sexual dysfunctions and their management (hyperprolactinemia, thyroid disorders, GH disorders, and DHEA). J Sex Med 2012; 10:661-77. [PMID: 22524444 DOI: 10.1111/j.1743-6109.2012.02735.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
INTRODUCTION Besides hypogonadism, other endocrine disorders have been associated with male sexual dysfunction (MSD). AIM To review the role of the pituitary hormone prolactin (PRL), growth hormone (GH), thyroid hormones, and adrenal androgens in MSD. METHODS A systematic search of published evidence was performed using Medline (1969 to September 2011). Oxford Centre for Evidence-Based Medicine-Levels of Evidence (March 2009) was applied when possible. MAIN OUTCOME MEASURES The most important evidence regarding the role played by PRL, GH, thyroid, and adrenal hormone was reviewed and discussed. RESULTS Only severe hyperprolactinemia (>35 ng/mL or 735 mU/L), often related to a pituitary tumor, has a negative impact on sexual function, impairing sexual desire, testosterone production, and, through the latter, erectile function due to a dual effect: mass effect and PRL-induced suppression on gonadotropin secretion. The latter is PRL-level dependent. Emerging evidence indicates that hyperthyroidism is associated with an increased risk of premature ejaculation and might also be associated with erectile dysfunction (ED), whereas hypothyroidism mainly affects sexual desire and impairs the ejaculatory reflex. However, the real incidence of thyroid dysfunction in subjects with sexual problems needs to be evaluated. Prevalence of ED and decreased libido increase in acromegalic patients; however, it is still a matter of debate whether GH excess (acromegaly) may create effects due to a direct overproduction of GH/insulin-like growth factor 1 or because of the pituitary mass effects on gonadotropic cells, resulting in hypogonadism. Finally, although dehydroepiandrosterone (DHEA) and its sulfate have been implicated in a broad range of biological derangements, controlled trials have shown that DHEA administration is not useful for improving male sexual function. CONCLUSIONS While the association between hyperprolactinemia and hypoactive sexual desire is well defined, more studies are needed to completely understand the role of other hormones in regulating male sexual functioning.
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Affiliation(s)
- Mario Maggi
- Sexual Medicine and Andrology Unit, Department of Clinical Physiopathology, University of Florence, Florence, Italy.
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Infertilität. GYNAKOLOGISCHE ENDOKRINOLOGIE 2012. [DOI: 10.1007/s10304-011-0446-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kumar A, Dewan R, Suri J, Kohli S, Shekhar S, Dhole B, Chaturvedi PK. Abolition of endocrine dimorphism in hyperthyroid males? An argument for the positive feedback effect of hyperoestrogenaemia on LH secretion. Andrologia 2012; 44:217-25. [PMID: 22211273 DOI: 10.1111/j.1439-0272.2011.01270.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/04/2011] [Indexed: 11/30/2022] Open
Abstract
Our aim was (i) to investigate the hypothalamo-hypophyseal-gonadal axis in hyperthyroid Indian males, (ii) to rule out the modulatory role of adrenal steroids on it and (iii) to determine if the simultaneous rise in oestradiol and luteinising hormone (LH) in hyperthyroid males is due to a positive feedback action of oestradiol on pituitary LH release. Age- and BMI-matched men were divided into two groups, I, euthyroid subjects (n = 17) and II, hyperthyroid patients (n = 12) on the basis of their thyroid hormone levels. Serum levels of thyroid-stimulating hormone, triiodothyronine, thyroxine, LH, follicle-stimulating hormone (FSH), prolactin, E(2), T, P(4), sex hormone binding globulin and dehydroepiandrosterone sulphate (DHEAS) were assayed. Mean levels of T and E(2) were approximately two times higher in group II in comparison with group I. DHEAS levels were similar in both groups ruling out any adrenal involvement. Mean serum LH level was 2.6 folds higher in group II in comparison with group I. Mean serum levels of FSH were higher in group II, it was marginally nonsignificant. On the basis of these and previous observations, we hypothesise that endocrinological dimorphism in human male and female is not rigid; a sustained rise in serum oestradiol probably induces a positive feedback action on pituitary leading to elevated gonadotrophin levels.
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Affiliation(s)
- A Kumar
- Department of Reproductive Biology, All India Institute of Medical Sciences, New Delhi, India.
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Abstract
Via its interaction in several pathways, normal thyroid function is important to maintain normal reproduction. In both genders, changes in SHBG and sex steroids are a consistent feature associated with hyper- and hypothyroidism and were already reported many years ago. Male reproduction is adversely affected by both thyrotoxicosis and hypothyroidism. Erectile abnormalities have been reported. Thyrotoxicosis induces abnormalities in sperm motility, whereas hypothyroidism is associated with abnormalities in sperm morphology; the latter normalize when euthyroidism is reached. In females, thyrotoxicosis and hypothyroidism can cause menstrual disturbances. Thyrotoxicosis is associated mainly with hypomenorrhea and polymenorrhea, whereas hypothyroidism is associated mainly with oligomenorrhea. Thyroid dysfunction has also been linked to reduced fertility. Controlled ovarian hyperstimulation leads to important increases in estradiol, which in turn may have an adverse effect on thyroid hormones and TSH. When autoimmune thyroid disease is present, the impact of controlled ovarian hyperstimulation may become more severe, depending on preexisting thyroid abnormalities. Autoimmune thyroid disease is present in 5-20% of unselected pregnant women. Isolated hypothyroxinemia has been described in approximately 2% of pregnancies, without serum TSH elevation and in the absence of thyroid autoantibodies. Overt hypothyroidism has been associated with increased rates of spontaneous abortion, premature delivery and/or low birth weight, fetal distress in labor, and perhaps gestation-induced hypertension and placental abruption. The links between such obstetrical complications and subclinical hypothyroidism are less evident. Thyrotoxicosis during pregnancy is due to Graves' disease and gestational transient thyrotoxicosis. All antithyroid drugs cross the placenta and may potentially affect fetal thyroid function.
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Affiliation(s)
- G E Krassas
- Department of Endocrinology, Diabetes, and Metabolism, Panagia General Hospital, N. Plastira 22, N. Krini, 55132 Thessaloniki, Greece.
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Proliferative thyroid lesions and hyperthyroidism in captive fishers (Martes pennanti). J Zoo Wildl Med 2010; 41:296-308. [PMID: 20597222 DOI: 10.1638/2009-0186r2.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Diseases of the thyroid gland are common in many zoo species, but there are few descriptions of thyroid dysfunction in Mustelidae. A 7-yr-old, captive-bred female fisher (Martes pennanti) with progressive alopecia was diagnosed with clinical hyperthyroidism based on persistent elevation of both total and free serum thyroxine and triiodothyronine, ultrasound examination, and histologic evidence of adenomatous hyperplasia. Four additional geriatric adult fishers (two male and two female) were identified with thyroid adenomatous hyperplasia in a review of 23 postmortem records. Banked sera were available for thyroid hormone testing from three of the four necropsy cases. Total and free thyroxine were elevated in four of four animals tested, and triiodothyronine was elevated in two of three animals tested. Necropsy findings in four cases identified cardiac hypertrophy, congestive heart failure, and vascular lesions consistent with hypertension; complete tissues were not available from the remaining case. Clinical and subclinical hyperthyroidism may be a common but overlooked condition of captive fishers.
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Wajner SM, Wagner MS, Maia AL. Clinical implications of altered thyroid status in male testicular function. ACTA ACUST UNITED AC 2009; 53:976-82. [PMID: 20126850 DOI: 10.1590/s0004-27302009000800011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Accepted: 10/16/2009] [Indexed: 11/22/2022]
Abstract
Thyroid hormones are involved in the development and maintenance of virtually all tissues. Although for many years the testis was thought to be a thyroid-hormone unresponsive organ, studies of the last decades have demonstrated that thyroid dysfunction is associated not only with abnormalities in morphology and function of testes, but also with decreased fertility and alterations of sexual activity in men. Nowadays, the participation of triiodothyronine (T3) in the control of Sertoli and Leydig cell proliferation, testicular maturation, and steroidogenesis is widely accepted, as well as the presence of thyroid hormone transporters and receptors in testicular cells throughout the development process and in adulthood. But even with data suggesting that T3 may act directly on these cells to bring about its effects, there is still controversy regarding the impact of thyroid diseases on human spermatogenesis and fertility, which can be in part due to the lack of well-controlled clinical studies. The current review aims at presenting an updated picture of recent clinical data about the role of thyroid hormones in male gonadal function.
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Abstract
PURPOSE OF REVIEW Radiometabolic therapy with radioactive iodine (I) is the standard treatment for differentiated thyroid cancer and is also currently the treatment of choice for Graves' disease in the United States. and in most countries. Men younger than 40 years of age represent about 10% of all radiometabolic treatments. Thus, the question arises whether I therapy is able to induce a damage to the fertility potential. RECENT FINDINGS The different effects caused by I therapy employed in cancer and hyperthyroid patients are reviewed. Most articles about the first category of patients show a damage to the germinal epithelium directly related to the cumulative dose delivered. Although the small amounts used in hyperthyroidism are usually well tolerated in terms of sterility risk, the impairment caused by hyperthyroidism per se is probably higher than that caused by I treatment. SUMMARY Young cancer patients, particularly those with node or lung metastases, who will probably undergo repeated treatments should be aware of the potential risks to their fertility. An evaluation of testicular function is thus advisable. When an impairment of fertility potential is already present, the option of freezing semen should be considered. The available studies concerning I therapy in hyperthyroidism suggest that this treatment does not cause a worsening of semen analysis but an amelioration in affected patients.
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Abstract
PURPOSE OF REVIEW This review highlights the 'gap' in knowledge regarding the contribution of thyroid dysfunction in reproduction. Thyroid dysfunction, which is quite prevalent in the population affects many organs including the male and female gonads, interferes with human reproductive physiology, reduces the likelihood of pregnancy and adversely affects pregnancy outcome, thus becoming relevant in the algorithm of reproductive dysfunction. RECENT FINDINGS Although menstrual irregularities are common, ovulation and conception can still occur in hypothyroidism, where thyroxine treatment restores a normal menstrual pattern and reverses hormonal changes. Subclinical hypothyroidism may be associated with ovulatory dysfunction and adverse pregnancy outcome. Thyroid autoimmunity increases the miscarriage rate, and thyroxine treatment does not seem to protect. Menstrual disturbances, frequent in thyrotoxicosis are restored following treatment. In males, thyrotoxicosis has a significant but reversible effect on sperm motility. Although radioactive Iodine (I) in ablation doses may transiently affect the gonads, it does not decrease fertility or increase genetic malformation rate in the offspring. SUMMARY Awareness of the thyroid status in the infertile couple is crucial, because of its significant, frequent and often reversible or preventable effect on infertility. Many aspects of the role of thyroid disorders however in infertility need further research.
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Ceccarelli C, Canale D, Battisti P, Caglieresi C, Moschini C, Fiore E, Grasso L, Pinchera A, Vitti P. Testicular function after 131I therapy for hyperthyroidism. Clin Endocrinol (Oxf) 2006; 65:446-52. [PMID: 16984236 DOI: 10.1111/j.1365-2265.2006.02613.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Radioiodine-131 is commonly used for treatment of hyperthyroidism but there are few available data on the effects of this treatment on male gonadal function. The untoward effects of (131)I have been mainly studied in male patients treated with high doses for thyroid cancer. In the present work we studied the absorbed radiation dose to the testes and testicular function in hyperthyroid men after (131)I treatment. PATIENTS AND MEASUREMENTS Nineteen male hyperthyroid patients were enrolled in the study before (131)I therapy. Seventeen of the patients had Graves' disease and two had toxic adenoma. The study was subdivided into two parts: a dosimetric and a clinical study. Six patients were enrolled for the dosimetric study and 13 for the clinical study. The beta dose delivered to the testes was evaluated by the Medical Internal Radiation Dose (MIRD) method. The gamma dose was measured by thermoluminescent dosimeters (TLDs) placed on the skin overlying the inferior poles of the testes for 3 weeks after therapy. The clinical evaluation included hormone determination, ultrasound (US) of the testes and sperm analysis. Patients were followed up for 12 months after (131)I therapy. RESULTS In the dosimetric study, the beta dose absorbed in the testes was 12.5 +/- 8.8 mGy (range 29-15 mGy) and the gamma dose was 15.8 +/- 5.3 mGy (range 24-11 mGy). The total dose to the testes for administered activity unit was 39 +/- 14 microGy/MBq (range 27-86 microGy/MBq). In the clinical study, FSH did not change significantly after (131)I treatment for the majority of patients. Serum testosterone (T) and the T/LH ratio were significantly reduced 45 days after treatment and returned to basal levels after 12 months. Ten out of 15 hyperthyroid patients (67%) had low sperm motility before treatment. A significant increase in progressive motility was observed after (131)I therapy (Friedman test chi(2) = 12.65, P = 0.01). Conversely, there was no significant variation in sperm concentration and percentage of normal forms after (131)I. CONCLUSIONS After (131)I therapy, germinal epithelium and Leydig cell function undergo only marginal changes, which may have some significance in subjects with a pre-existing fertility impairment.
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Hogervorst E, Bandelow S, Combrinck M, Smith AD. Low free testosterone is an independent risk factor for Alzheimer's disease. Exp Gerontol 2005; 39:1633-9. [PMID: 15582279 DOI: 10.1016/j.exger.2004.06.019] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2004] [Accepted: 06/01/2004] [Indexed: 10/26/2022]
Abstract
The purpose of this study was to assess pituitary gonadotropins and free testosterone levels in a larger cohort of men with Alzheimer's disease (AD, n=112) and age-matched controls (n=98) from the Oxford Project to Investigate Memory and Ageing (OPTIMA). We measured gonadotropins (follicle stimulating hormone, FSH, and luteinizing hormone, LH), sex hormone binding globulin (SHBG, which determines the amount of free testosterone) and total testosterone (TT) using enzyme immunoassays. AD cases had significantly higher LH and FSH and lower free testosterone levels. LH, FSH and SHBG all increased with age, while free testosterone decreased. Low free testosterone was an independent predictor for AD. Its variance was overall explained by high SHBG, low TT, high LH, an older age and low body mass index (BMI). In controls, low thyroid stimulating hormone levels were also associated with low free testosterone. Elderly AD cases had raised levels of gonadotropins. This response may be an attempt to normalize low free testosterone levels. In non-demented participants, subclinical hyperthyroid disease (a risk factor for AD) which can result in higher SHBG levels, was associated with low free testosterone. Lowering SHBG and/or screening for subclinical thyroid disease may prevent cognitive decline and/or wasting in men at risk for AD.
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Affiliation(s)
- E Hogervorst
- Oxford Project to Investigate Memory and Ageing, Department of Pharmacology, University of Oxford, Radcliffe Infirmary, Woodstock Rd, Oxford, OX2 6HE, UK.
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Krassas GE, Pontikides N. Male reproductive function in relation with thyroid alterations. Best Pract Res Clin Endocrinol Metab 2004; 18:183-95. [PMID: 15157835 DOI: 10.1016/j.beem.2004.03.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/09/2004] [Indexed: 10/26/2022]
Abstract
Despite the high prevalence of thyroid diseases in the general population, the impact of the latter on male reproductive function has been the subject of only a few well-controlled clinical studies. Hyperthyroidism appears to cause alterations in the sex steroid hormone metabolism as well as in spermatogenesis and fertility. Sperm motility is mainly affected. These abnormalities reverse after restoration of euthyroidism. The effects of hypothyroidism on male reproduction appear to be more subtle than those of hyperthyroidism and reversible. Severe juvenile hypothyroidism may be associated with precocious puberty. Hypothyroidism in adults is associated with disturbances in the sex steroid hormone metabolism as well as infertility, although available data concerning the latter are scarce. Radioiodine ((131)I) treatment for dfferentiated thyroid cancer may cause transient impairment of testicular function Gonadal damage may be cumulative in those requiring multiple administrations and sperm banking should be considered in such patients.
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Affiliation(s)
- Gerasimos E Krassas
- Department of Endocrinology, Diabetes and Metabolism, Panagia General Hospital, N. Plastira 22, N. Krini, 55132 Thessaloniki, Greece.
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Abstract
Thyroid hormone deficiency affects all tissues of the body, including multiple endocrine changes that alter growth hormone, corticotrophin, glucocorticoids, and gonadal function. Primary hypothyroidism is associated with hypogonadotropic hypogonadism, which is reversible with thyroid hormone replacement therapy. In male children follicle-stimulating hormone (FSH) is elevated and associated with testicular enlargement without virilization. Men with primary hypothyroidism have subnormal responses of luteinizing hormone (LH) to gonadotropin-releasing hormone (GnRH) administration and normal response to human chorionic gonadotropin (hCG). Free testosterone concentrations are reduced in men with primary hypothyroidism and thyroid hormone replacement normalizes free testosterone concentrations. In men with primary hypothyroidism, prolactin is not consistently elevated (except in men and children with longstanding severe primary hypothyroidism), but prolactin declines following thyroid hormone replacement therapy. Thyroid hormone is known to affect sex hormone-binding hormonal globulin (SHBG) concentrations. Men with hyperthyroidism have elevated concentrations of testosterone and SHBG. Thyroid hormone therapy in normal men may also duplicate this elevation. In addition estradiol elevations are observed in men with hyperthyroidism, and gynecomastia is common in them as well. In contrast to patients with primary hypothyroidism, men with hyperthyroidism exhibit hyperresponsiveness of LH to GnRH administration and subnormal responses to hCG. Radioactive iodine therapy (RAI) of men treated for thyroid cancer produces a dose-dependent impairment of spermatogenesis and elevation of FSH up to approximately 2 years. Permanent testicular germ cell damage may occur in men treated with high doses of RAI. RAI commonly increases serum concentrations of FSH and LH while reducing inhibin B levels without affecting serum concentrations of testosterone. Thus, radioiodine therapy transiently impairs both germinal and Leydig cell function that usually recover by 18 months posttherapy.
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Affiliation(s)
- A Wayne Meikle
- Division of Endocrinology, University of Utah School of Medicine, Endocrine Testing Laboratory ARUP, 615 Arapeen Drive, Salt Lake City, UT 84108, USA.
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