Author Interviews, Endocrinology, Genetic Research, NYU / 19.06.2017

MedicalResearch.com Interview with: Constantine A. Stratakis, MD, DMSci Section on Endocrinology and Genetics Eunice Kennedy Shriver National Institute of Child Health and Human Development National Institutes of Health, Bethesda  MedicalResearch.com: What is the background for this study? Response: The pituitary and adrenal glands operate on a kind of feedback loop.  In response to stress, the pituitary release ACTH (Adrenocorticotropic hormone), which signals the adrenal glands to release cortisol.  Rising cortisol levels then act on the pituitary, to shut down ACTH production. In a previous study, Jacque Drouin of the Institute for Clinical Research in Montreal and colleagues had determined that the CABLES1 protein was a key player in this feedback mechanism, switching off pituitary cell division in cultures exposed to cortisol. Since this feedback mechanism appears to be impaired in many corticotropinomas, we investigated the presence of Cables1 gene mutations and copy number variations in a large group of patients with Cushing’s disease. (more…)
Author Interviews, JCEM, Surgical Research, Thyroid, University of Michigan / 18.05.2017

MedicalResearch.com Interview with: Megan Rist Haymart MD Assistant Professor University of Michigan MedicalResearch.com: What is the background for this study? What are the main findings? Response: Thyroid cancer is typically treated with thyroid surgery. It is common practice for physicians to inform patients that the risk of vocal cord paralysis or hypoparathyroidism with thyroid surgery is 1-3%. However, most of these estimates are based on single institution studies with high volume surgeons. In our study we evaluated surgical risks in a population-based cohort. Using the Surveillance, Epidemiology, and End Results-Medicare database, we found that 6.5% of thyroid cancer patients developed general post-operative complications (fever, infection, hematoma, cardiopulmonary and thromboembolic events) and 12.3% developed thyroid surgery specific complications (hypoparathyroidism/hypocalcemia, vocal cord/fold paralysis). Older patient age, presence of comorbidities, and advanced stage disease were associated with the greatest risks of surgical complications. (more…)
Author Interviews, Biomarkers, Endocrinology, NIH / 10.02.2017

MedicalResearch.com Interview with: Mihail Zilbermint, M.D. Endocrinologist, Office of the Scientific Director Mihail Zilbermint, M.D. Endocrinologist, Office of the Scientific Director Eunice Kennedy Shriver National Institute of Child Health and Human Development National Institutes of Health Eunice Kennedy Shriver National Institute of Child Health and Human Development National Institutes of Health  MedicalResearch.com: What is the background for this study? Response: Diagnosing Cushing Syndrome is often difficult and challenging.  Diagnosing hypercortisolemia, could require the use of a combination of any of these tests: 24-hour free urine cortisol monitoring, an overnight dexamethasone suppression test, and measurement of late night salivary cortisol.  Cortisol levels may change daily, requiring that testing be repeated.  Undiagnosed and untreated Cushing Syndrome greatly increases morbidity and mortality risk. Cortisol levels can be detected in hair samples.  Much like hemoglobin A1C is a long-term indicator of blood glucose levels, efforts have been made to determine if hair cortisol could serve as a long-term measure of the body’s glucocorticoid levels.  We sought to compare the results of cortisol levels for Cushing Syndrome patients with data from data on cortisol in hair segments, to gain further information on the role of sampling hair cortisol as an initial or supportive method for diagnosing Cushing Syndrome. (more…)
Author Interviews, Endocrinology, Gender Differences, JCEM / 13.01.2017

MedicalResearch.com Interview with: Caroline J. Davidge-Pitts, M.B., Ch.B Mayo Clinic Rochester, Minn. MedicalResearch.com: What is the background for this study? Response: The awareness of transgender healthcare issues has increased, leading to improved coverage of both hormonal and non-hormonal therapies. In endocrinology practices, there is an increased demand for providers who are competent in these areas. We wanted to assess the current status of knowledge and practice in transgender health amongst our current and future endocrinologists. (more…)
Author Interviews, BMJ, Clots - Coagulation, Testosterone, Thromboembolism / 03.12.2016

MedicalResearch.com Interview with: Dr. Carlos Martinez Institute for Epidemiology, Statistics and Informatics GmbH Frankfurt, Germany, MedicalResearch.com: What is the background for this study? Response: A 10-fold increase in testosterone prescriptions per capita in the United States and a 40-fold increase in Canada in men has occurred over the first decade of this century, mainly for sexual dysfunction and/or decreased energy. Recognised pathological disorders of the male reproductive system remain the sole unequivocal indication for testosterone treatment but there has been increasing use in men without pathological hypogonadism. A variety of studies and meta-analyses have provided conflicting evidence as to the magnitude of the risk of cardiovascular events including venous thromboembolism in men on testosterone treatment. In June 2014, the US Food and Drug Administration and Health Canada required a warning about the risk of venous thromboembolism to be displayed on all approved testosterone products. Studies have reported contradictory results on an association between testosterone use and the risk of venous thromboembolism. The effect of timing and duration of testosterone use on the risk of venous thromboembolism was not studied and may explain some of these contradictory findings. (more…)
Author Interviews, Endocrinology, Menopause, Osteoporosis / 27.10.2016

MedicalResearch.com Interview with: Pauline Camacho, MD, FACE Professor, Endocrinology Director, Loyola University Osteoporosis and Metabolic Bone Disease Center, Fellowship Program Director, Endocrinology, Medical Director, Osteoporosis Center MedicalResearch.com: What is the background for this report? What is the prevalence and significance of osteoporosis in US women? Response: Osteoporosis is widely prevalent and is increasing in prevalence not only in the US but also around the world. 10.2 million Americans have osteoporosis and that an additional 43.4 million have low bone mass. More than 2 million osteoporosis-related fractures occur annually in the US, more than 70% of these occur in women ( from National Osteoporosis Foundation (NOF) estimates). (more…)
Author Interviews, Endocrinology, JCEM, Thyroid Disease / 14.10.2016

MedicalResearch.com Interview with: Antonio C. Bianco, MD, PhD Rush University Medical Center MedicalResearch.com: What is the background for this study? What are the main findings? Response: The standard of care for patients with hypothyroidism is treatment with levothyroxine. The dosage of levothyroxine is adjusted for each patient with the goal of normalizing blood levels of TSH. About 15% of the patients treated this way exhibit variable degrees of residual symptoms, despite having a normal TSH level. These symptoms include difficulty losing weight, low energy and depression. However, given the subjective nature of these complains and that the blood levels of TSH are normal, many times such symptoms are dismissed by physicians as non-thyroid related. (more…)
Author Interviews, Endocrinology, JCEM, Kidney Disease, Mineral Metabolism / 03.10.2016

MedicalResearch.com Interview with: Jonas Esche Dipl.-Mol. Biomed University of Bonn Institute of Nutritional and Food Sciences DONALD Study MedicalResearch.com: What is the background for this study? Response: Modern western diets increase diet-dependent acid load and net acid excretion which are suggested to have adverse long-term effects on bone. Urinary potential renal acid load (uPRAL) is an established parameter to assess nutritional acid load. Urinary citrate, on the other hand, integrates nutritional and also systemic influences on acid-base homeostasis with high citrate indicating prevailing alkalization. Against this background urinary citrate excretion was used as a new index of acid-base status and its relationship with bone strength and long-term fracture risk was examined. (more…)
Author Interviews, Diabetes, Endocrinology, Hormone Therapy / 19.09.2016

MedicalResearch.com Interview with: Jon Rasmussen, MD, PhD fellow Department of Internal Medicine Herlev Hospital, Denmark MedicalResearch.com: What is the background for this study? Response: Abuse of anabolic androgenic steroids has become highly prevalent among young men involved in recreational strength training. A recent meta-analysis estimated that approximately 18% of young men involved recreational strength training abuse anabolic steroids. Well-known adverse effects following abuse of anabolic steroids include hypogonadism (For those who have interest, we have recently published a paper concerning this issue, it can be read and downloaded at: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0161208). Yet, we have a poor understanding on the adverse effects these compounds might have on the metabolism and insulin sensitivity. (more…)
Author Interviews, Breast Cancer, Endocrinology, OBGYNE / 13.09.2016

MedicalResearch.com Interview with: Leena Hilakivi-Clarke, PhD Professor of Oncology Georgetown University Washington, DC 20057 MedicalResearch.com: What is the background for this study? Response: About 70% of women who develop breast cancer express estrogen receptors in their cancer. These patients are treated with endocrine therapies that target estrogen receptors. Endocrine therapies are effective in half of the patients, but the other half are resistant to the treatment and recur. Prior to the start of endocrine therapy, there is no way to predict who will respond to it and who will have recurrence of breast cancer. Therefore, it is not known which patients might benefit from an additional therapy to prevent recurrence, and what that additional therapy would entail. We wondered if resistance to endocrine therapy (we used tamoxifen) is pre-programmed by maternal exposure to the estrogenic endocrine disrupting chemical ethinyl estradiol (EE2). Previously, we and others have found that EE2 and other estrogenic compounds, when given during pregnancy, increase breast cancer risk in the female offspring in animal studies and among humans. The current study was done using a preclinical animal model that was used 50 years ago to discover that tamoxifen is an effective endocrine therapy for estrogen receptor positive breast cancer patients. (more…)
Author Interviews, Dermatology, Endocrinology, Fertility / 03.09.2016

MedicalResearch.com Interview with: Anders Rehfeld MD, PhD Student Faculty of Health and Medical Sciences Department of Cellular and Molecular Medicine University of Copenhagen Copenhagen Denmark MedicalResearch.com: What is the background for this study? What are the main findings? Response: Human fertility is declining in many areas of the world and the reason is largely unknown. Our study shows that 44% of the tested chemical UV filters can induce calcium signals in human sperm cells, thereby mimicking the effect of progesterone. Progesterone-induced calcium signals, and the sperm functions it triggers, is absolutely essential for the human sperm cell to normally fertilise the human egg. (more…)
Author Interviews, Endocrinology, JCEM, NIH, Vitamin D / 08.08.2016

MedicalResearch.com Interview with: Quaker Harmon M.D., Ph.D. Epidemiology Branch National Institute of Environmental Health Sciences Research Triangle Park, NC 27709 MedicalResearch.com: What is the background for this study? What are the main findings? Response: Vitamin D is important for bone health. In the United States many women are vitamin D deficient. Vitamin D does not naturally occur in many foods, however some foods are fortified with vitamin D. Supplements and sunshine are the most reliable sources of vitamin D. Previous studies suggested that women using birth control pills containing estrogen had higher levels of vitamin D. These studies were generally small and were not always able to examine important factors such as time spent outside. We were interested in examining the association between hormonal contraception and vitamin D levels in a larger group of women. We found that women who use estrogen-containing contraception had a 20% increase in their vitamin D levels. This increase was not due to time spent outside or behaviors related to choice of contraception. The magnitude of increase for hormonal contraception was smaller than for regular use of a supplement containing vitamin D. (more…)
Author Interviews, Endocrinology, Hematology, OBGYNE, Thyroid Disease / 24.07.2016

MedicalResearch.com Interview with: Kris Poppe, MD, PhD Co-Head Endocrine Unit CHU St-Pierre UMC Université libre de Bruxelles MedicalResearch.com: What is the background for this study?  Response: Pregnant women are often referred by gynecologists to my endocrine practice, for altered thyroid function. At that occasion, I often noticed that the women also had low iron/ferritin levels (ferritin is the iron reserve). Searching in literature did not reveal many publications on the association between iron (deficiency) and thyroid function during pregnancy and so that was the background/aim to perform this study. (more…)
Author Interviews, Baylor College of Medicine Houston, Endocrinology, Sexual Health, Testosterone / 01.07.2016

MedicalResearch.com Interview with: Glenn Cunningham, MD Departments of Medicine and Molecular and Cellular Biology Division of Diabetes, Endocrinology and Metabolism Baylor College of Medicine and Baylor St. Luke's Medical Center Houston, Texas 77030 MedicalResearch.com: What is the background for this study? Response: The Testosterone Trials are a coordinated set of seven trials to determine the efficacy of testosterone in symptomatic men ≥65 years with unequivocally low testosterone levels. Previous studies in older men have been limited and the results have been conflicting. Initial results of the Sexual Function Trial showed that testosterone improved sexual activity, sexual desire and erectile function. (more…)
Author Interviews, Diabetes, Endocrinology, Environmental Risks, Lipids / 27.05.2016

MedicalResearch.com Interview with: Maayan Yitshak Sade MPH Chief Scientific Officer Clinical Research Center, Soroka University Medical Center, Israel and   Victor Novack, MD, PhD Soroka University Medical Center and Ben-Gurion University in Beer Sheva, Israel   MedicalResearch.com: What is the background for this study? Response: Numerous studies found association between exposure the air pollution and increased risk of cardiovascular and respiratory diseases. In recent years links were found between air pollution and diabetes as well. The scientific evidence supports a causal association between air pollution and oxidative stress, possibly involving impaired metabolism of glucose and lipids. In a recent study performed by our group, we observed a significantly increased risk for ischemic stroke among young adults, associated with air pollution exposure. Following these findings, and as a part of the possible theory linking the association air pollution exposure and cardiovascular diseases, we sought to investigate if this association might be mediated through the well-established cardiovascular risk factors such as abnormal lipid and glucose metabolism. (more…)
Author Interviews, Dermatology, Endocrinology, UCSF / 27.12.2015

MedicalResearch.com Interview with: Kanade Shinkai, MD PhD Associate Professor of Clinical Dermatology Director, Residency Program Endowed Chair in Dermatology Medical Student Education UCSF Department of Dermatology San Francisco, CA 94115  Medical Research: What is the background for this study? What are the main findings? Dr. Shinkai: Polycystic Ovary Syndrome (PCOS) is a common endocrine disorder in the United States that has important skin manifestations including acne, hair loss, hirsutism, and acanthosis nigricans. We performed a retrospective cross-sectional study of women referred to a multidisciplinary PCOS clinic at UCSF to determine whether skin findings and systemic associations differ between women who meet diagnostic criteria for PCOS versus those suspected of having PCOS but do not meet diagnostic criteria. We found that women with PCOS commonly have skin findings, however, present across a broad spectrum of cutaneous manifestations. Comparing the skin findings in women who meet diagnostic criteria for PCOS with women who are suspected of having PCOS suggests that it can be very difficult to distinguish a patient with PCOS based on skin findings alone.  Hirsutism and acanthosis nigricans are the most helpful findings to suggest PCOS and require a comprehensive skin examination to diagnose; acne and androgenic alopecia are common findings but do not differentiate. The finding of hirsutism and acanthosis were associated with important systemic abnormalities including elevated free testosterone levels, insulin resistance, obesity, and dyslipidemia. This is the first study to perform systematic comprehensive skin exams on women with PCOS and link the skin findings to key systemic associations that have significant implications for the treatment and prognosis of women with the disease. (more…)
Author Interviews, Endocrinology, Kidney Disease, Transplantation, Vitamin K / 21.12.2015

MedicalResearch.com Interview with: Josep M Cruzado, MD Head, Nephrology Department Hospital Universitari de Bellvitge  Medical Research: What is the background for this study? What are the main findings? Dr. Cruzado: Tertiary hyperparathyroidism is frequent after renal transplantation. Inappropriately high parathyroid hormone levels are associated with hypercalcemia, hyperphosphatemia, both allograft and vascular calcification and bone mineral density loss. Cinacalcet is highly effective to control hypercalcemia in this setting although there were no studies comparing cinacalcet with subtotal parathyroidectomy. Main findings are that subtotal parathyroidectomy is superior to cinacalcet in normalizing hypercalcemia amb iPTH, increased bone mineral density at femoral neck and is more cost effective (the cost of subtotal parathyroidectomy is equal to 14 months of cinacalcet and this drug should be maintained overtime). (more…)
Author Interviews, Cancer Research, Endocrinology, JAMA, Menopause / 05.10.2015

Rodrigo R. Munhoz, MD Hospital Sírio Libanês São Paulo, Brazil MedicalResearch.com Interview with: Rodrigo R. Munhoz, MD Hospital Sírio Libanês São Paulo, Brazil  Medical Research: What is the background for this study? What are the main findings? Dr. Munhoz:  Chemotherapy-induced early menopause and its impact on quality of life is clinically relevant issue that often arises during the treatment with curative intent of premenopausal patients with early breast cancer. The use of neo-/adjuvant chemotherapy is associated with risks of ovarian dysfunction, permanent or transient amenorrhea, infertility and symptoms of menopause with a premature onset. In addition to osteoporosis, loss of libido, increased cardiovascular risk and atrophic vaginitis, early ovarian dysfunction may adversely impact quality of life and result in significant psychosocial burden. Currently available guidelines addressing fertility preservation in young women undergoing treatment for early breast cancer recommend that patients at reproductive ages should be advised about the potential risks of fertility impairment and additional effects of adjuvant chemotherapy and that preservation techniques should be carefully considered. However, “evidence regarding the effectiveness of ovarian suppression” is quoted as “insufficient” and the use GnRH agonists as “experimental” . The current meta-analysis includes a large number of patients and also the results of recently presented clinical trials, and suggest that the use of GnRH agonists is associated a higher rate of recovery of regular menses in patients with breast cancer undergoing chemotherapy.These results summarize the findings of different clinical trials and has immediate clinical implications - this was not clear in the literature, since negative results had been reported across different clinical trials. (more…)
Author Interviews, Endocrinology, JAMA, Radiology, Surgical Research, UCSF / 28.07.2015

Quan-Yang Duh MD Endocrine surgeon UCSF Medical CenterMedicalResearch.com Interview with: Quan-Yang Duh MD Chief, Section of Endocrine Surgery UCSF Medical Center Medical Research: What is the background for this study? What are the main findings? Dr. Quan-Yang Duh: At UCSF we have a monthly Adrenal Conference (involving surgeons, endocrinologists and radiologists) to discuss patients we are consulted for adrenal tumors. About 30% of these are for incidentally discovered adrenal tumors (versus those found because of specific indications such as clinical suspicion or genetic screening). Of these 15-20% has bilateral adrenal tumors. The evaluation of unilateral incidentaloma has been very well studied and many national guidelines have been published with specific management recommendations. So during our monthly adrenal conference, we have a routine "script" for evaluation and recommendations (rule out metastasis by looking for primary cancer elsewhere, rule out pheochromocytoma and Cushing, resect secreting tumors or large tumors, and if no operation recommended repeat scan in 6 months, etc.). This “script” has worked very well for patients with unilateral incidentaloma. However, we were less certain when we made recommendations about bilateral incidentalomas because there was very little literature or guidelines written about it. We had some gut feelings, but we were not sure that we were recommending the right things. We needed more data. That was the main reason for the study. What we found in our study was that although the possible subclinical diseases were the same – hypercortisolism and pheochromocytoma, the probabilities were different. The patients with bilateral incidentalomas were more likely to have subclinical Cushing’s and less likely to have pheochromocytomas than those with unilateral incidentalomas. (more…)
Author Interviews, CDC, Endocrinology, JCEM / 16.07.2015

MedicalResearch.com Interview with: Hubert W. Vesper, PhD Director, Clinical Standardization Programs in the National Center for Environmental Health, Centers for Disease Control and Prevention Co-author, “Measuring Estrogen Exposure and Metabolism: Workshop Recommendations on Clinical Issues” Co-chair of the PATH Steering Committee Medical Research: What is the background for this study? What are the main findings? Dr. Vesper: Accurate data on estrogen levels are needed to ensure appropriate and effective patient care. Research studies found high inaccuracies among different estrogen tests, especially at low estrogen levels commonly observed in postmenopausal women, men and children. Accurate estrogen measurements can be achieved through standardization. Stakeholders should support standardization efforts of the Centers for Disease Control and Prevention (CDC) or alternative strategies to arrive at estrogen measurement methods that are accuracy-based and reliable. (more…)
Author Interviews, Diabetes, Endocrinology, JAMA / 21.06.2015

MedicalResearch.com Interview with: Francis de Zegher, MD, PhD Department of Development and Regeneration, University of Leuven Leuven, Belgium & Lourdes Ibáñez, MD, PhD Hospital Sant Joan de Déu, University of Barcelona Barcelona, Spain Medical Research: What is the background for this study? Response: Hyperinsulinemic androgen excess is the most frequent hormonal disorder of adolescent girls. It seems to be mainly driven by an excessive and/or inappropriate storage of fat due to a chronically positive energy balance. The traditional approach (not approved by FDA or EMA) is to silence the ovaries by giving an oral contraceptive. An alternative approach is to change the storage of fat by giving an insulin-sensitizing combination of generics in low dose. (more…)
Author Interviews, Heart Disease / 10.03.2015

MedicalResearch.com Interview with:Elaine W. Yu, MD, MMSc Assistant Professor of Medicine Harvard Medical School Massachusetts General Hospital MGH Endocrine Unit Elaine W. Yu, MD, MMSc Assistant Professor of Medicine Harvard Medical School Massachusetts General Hospital MGH Endocrine Unit Medical Research: What is the background for this study? What are the main findings? Dr. Yu: It is well known that cardiovascular disease is more common in men than in women.  The exact reasons for this are unknown, but may be related to gender differences in levels of sex hormones such as testosterone and estrogen.  As compared to premenopausal women, men have higher testosterone and lower estrogen levels.  It is currently unclear whether the actions of testosterone and/or estrogen affect cardiovascular risk factors. In this study, we explored the regulation of cardiovascular risk factors by testosterone and estrogen in men. We found that higher levels of testosterone led to lower HDL levels (“good” cholesterol), whereas estrogen did not regulate HDL.  In contrast, low levels of estrogen led to worsening insulin resistance and increased muscle fat, markers for developing diabetes.  Importantly, LDL cholesterol (“bad” cholesterol”) was not affected by either testosterone or estrogen in men.   (more…)
Author Interviews, Endocrinology, JAMA, Thyroid Disease / 05.03.2015

Sebastiano Filetti MD Dipartimento di Medicina Interna Università di Roma RomaMedicalResearch.com Interview with; Sebastiano Filetti MD Dipartimento di Medicina Interna Università di Roma Roma MedicalResearch: What is the background for this study? What are the main findings? Dr. Filetti: Thyroid nodule diagnosis is becoming more and more frequent in clinical practice. This trend stems largely from the incidental discovery of small nodules due to the increased use of diagnostic imaging for purposes unrelated to the thyroid. Ultrasound studies, for example, are widely used for evaluating other structures in the neck, such as the carotid arteries, parathyroid glands, lymph nodes, and salivary glands. Over 90% of detected thyroid nodules are clinically insignificant, in that they have been cytologically proven to be benign or they have no ultrasound features that raise the suspicion of malignancy. However, consensus is lacking regarding the best way to follow these nodules, mainly because little is known about the actual frequency and magnitude of their growth. The results of our study suggest that most benign nodules exhibit no significant size changes over time, and some actually decrease in size. Only a small subgroup of nodules can be expected to grow, about 15% in our series. However, the growth is slow and limited in magnitude. Most important, the occurrence of cancer is very rare in nodules like this, that appear to be benign. (more…)
Author Interviews, Endocrinology, Sexual Health / 15.02.2015

Joshua D. Safer MD, FACP Director, Endocrinology Fellowship Training and Endocrinology Education Boston University Medical Center Associate Professor of Medicine and Molecular Medicine Boston University School of Medicine MedicalResearch.com Interview with: Joshua D. Safer MD, FACP Director, Endocrinology Fellowship Training and Endocrinology Education Boston University Medical Center Associate Professor of Medicine and Molecular Medicine Boston University School of Medicine   Medical Research: What is the background for this study? What are the main findings? Dr. Safer: This is a review of the current medical literature in favor of the biologic nature of gender identity.  The main barrier to medical care for transgender patients is lack of physicians with the knowledge and willingness to provide that care. A major concern of physicians is that this is a mental health issue, meaning that transgender hormone therapy and surgery may be too drastic a response to an individual who should be counseled instead.  The review lays out the evidence to make it clear that a major component of gender identity is biologic even if we don’t have the exact details worked out.  Therefore, counseling alone cannot address the disconnect between transgender individuals’ gender identity and their physical bodies. (more…)
Author Interviews, Endocrinology, Toxin Research / 05.02.2015

Dr. Andrea Gore PhD Gustavus & Louise Pfeiffer Professor University of Texas Austin/Div of Pharmacology/ToxicoMedicalResearch.com Interview with: Dr. Andrea Gore PhD Gustavus & Louise Pfeiffer Professor University of Texas Austin/Div of Pharmacology/Toxicology MedicalResearch.com Editor’s Note: Dr. Gore, Editor-in-Chief of the Journal Endocrinology, has graciously answered several questions regarding the recent concerns of environmental chemicals linked to both early puberty and early menopause. Medical Research: How can chemicals found inside the home impact onset of menopause? Dr. Gore: It is important to clarify that the cause-and-effect relationship between chemicals and menopause is not established. The timing of menopause in women is due to a variety of factors including genetic traits, nutritional status, and general health or chronic disease. Some research on humans, including the recent study by Grindler et al., also suggests that environmental chemicals may contribute to the timing of earlier menopause. Animal models also suggest an advance in the timing of reproductive failure following earlier life exposures to endocrine-disrupting chemicals (EDCs). [See references below]. The question of exactly how chemicals may change the timing of menopause is therefore unresolved, but based on animal studies it is likely that the mechanisms include effects of endocrine-disrupting chemicals on the expression of genes and proteins involved in ovarian function that may lead to premature loss of follicles (eggs). Because the control of reproduction involves the brain and the pituitary gland, as well as the ovary, it is possible that endocrine-disrupting chemicals also impair how these organs regulate reproductive hormones.
  1. Gore AC, Walker DM, Zama AM, Armenti AE, Uzumcu M. Early life exposure to endocrine-disrupting chemicals causes lifelong molecular reprogramming of the hypothalamus and premature reproductive aging. Mol Endocrinol. 2011;25:2157–2168.
  2. Shi Z, Valdez KE, Ting AY, Franczak A,GumSL, Petroff BK. Ovarian endocrine disruption underlies premature reproductive senescence following environmentally relevant chronic exposure to the aryl hydrocarbon receptor agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin. Biol Reprod. 2007;76:198–202.
  3. Akkina J, Reif J, Keefe T, Bachand A. Age at natural menopause and exposure to organochlorine pesticides in Hispanic women. J Toxicol Environ Health A. 2004;67:1407–1422.
  4. Cooper GS, Savitz DA, Millikan R, Chiu Kit T. Organochlorine exposure and age at natural menopause. Epidemiology. 2002;13: 729–733.
  5. Hatch EE, Troisi R, Wise LA, et al. Age at natural menopause in women exposed to diethylstilbestrol in utero. Am J Epidemiol. 2006;164:682–688.
  6. KnoxSS, Jackson T, Javins B, Frisbee SJ, Shankar A, DucatmanAM. Implications of early menopause in women exposed to perfluorocarbons. J Clin Endocrinol Metab. 2011;96:1747–1753.
  7. Farr SL, Cai J, Savitz DA, Sandler DP, Hoppin JA, Cooper GS. Pesticide exposure and timing of menopause: the Agricultural Health Study. Am J Epidemiol. 2006;163:731–742.
Medical Research: What are the primary sources of exposure to these chemicals? Dr. Gore: Endocrine-disrupting chemicals exposures come from a variety of sources, including plastic containers (e.g. water bottles) and other products, certain foods, personal care products, pesticides, and many others. (more…)
Author Interviews, Endocrinology, Health Care Systems, JCEM / 09.07.2014

Robert A. Vigersky, MD Walter Reed National Military Medical Center Bethesda, MDMedicalResearch.com Interview with: Robert A. Vigersky, MD Walter Reed National Military Medical Center Bethesda, MD Medical Research: What type of patients do endocrinologists typically treat and why is the demand for their services anticipated to grow? Dr. Vigersky: Endocrinologists are physicians trained in managing, diagnosing, and treating disorders of the endocrine system:  thyroid, parathyroid, adrenal glands, hypophyseal and hypothalamic axes, ovaries, testes, and pancreas.  Their role involves controlling diabetes mellitus, menopause, hyperthyroidism and other conditions involving metabolism. A major factor affecting the anticipated demand for health care services is the aging population.  In 2010, there were 37.5 million people age 65 or over, constituting about 12.7 percent of the total population, and by 2025 the population age 65 or over will number 62.5 million (17.9 percent of the population).  Due to the greater prevalence of many of the diseases in older age groups, like osteoporosis, diabetes, obesity, and thyroid nodules, the growth in the population age 65 or over will exert a major influence on the demand for endocrine services. Diabetes, by itself, is a major driver of demand.  The incidence of Type 2 diabetes rises dramatically with age, and with obesity.  In an increasingly overweight population an estimated 22.3 million people in the U.S. are diagnosed with diabetes as of 2012, representing about 7 percent of the population. This estimate is higher than but consistent with those published by the CDC for 2010.  The percentage of the population with diagnosed diabetes continues to rise, with one study projecting that as many as one in three U.S. adults could have diabetes by 2050 if current trends continue. (more…)
Author Interviews, Endocrinology, OBGYNE / 17.06.2014

Sergio R. Ojeda, D.V.M. Division Head and Senior Scientist Division of Neuroscience Division of Neuroscience, OR National Primate Research Center/Oregon Health and Science University, Beaverton OR 97006MedicalResearch.com Interview with: Sergio R. Ojeda, D.V.M. Division Head and Senior Scientist Division of Neuroscience Division of Neuroscience, OR National Primate Research Center/Oregon Health and Science University, Beaverton OR 97006 MedicalResearch: What are the main findings of the study? Dr. Ojeda: The study shows that a receptor for two growth factors (brain-derived neurotrophic factor [BDNF] and neurotrophin 4/5  [NT4/5]) that are known to be important for development of the nervous system is also essential for maintaining oocyte integrity and survival in the mammalian ovary. Intriguingly, the full-length form of this receptor (known as NTRK2-FL) is not expressed in oocytes until the time of the first ovulation. At this time,  the pre-ovulatory gonadotropin discharge stimulates granulosa cells of ovarian follicles to produce not only more BDNF, but also more of a peptide known as kisspeptin, to induce the formation of NTRK2-FL in oocytes. To date, kisspeptin was known to be  only critical for the hypothalamic control of reproduction. To induce NTRK2-FL, BDNF binds to truncated NTRK2 receptors (NTRK2-T1), which are abundant in oocytes throughout prepubertal development.  Kisspeptin, on the other hand, does so by activating its receptor KISS1R, also expressed in oocytes. Once present after the first ovulation, NTRK2-FL is able to activate a survival pathway in oocytes following gonadotropin stimulation, presumably at every cycle. In the absence of NTRK2-FL, oocytes die, follicular structure disintegrates and a condition of premature ovarian failure ensues. (more…)
Author Interviews, Endocrinology / 18.12.2013

MedicalResearch.com Interview with: Christopher D Kassotis  (MU-Student) Department of Obstetrics, Gynecology and Women’s Health and Division of Biological Sciences University of Missouri, Columbia, MO 65211; MedicalResearch.com: What are the main findings of the study? Answer: The main findings of our study are twofold: First, we found that 12 chemicals used in the fracking process disrupt hormone action. Specifically, we found that they inhibited the action of estrogens such as estradiol and androgens such as testosterone; classes of reproductive hormones that are critical for normal development and reproductive maturation. Second, we found that surface and ground water from a drilling-dense area in Colorado has much greater hormonal activity than samples from areas with limited drilling. Specifically, ground water had elevated estrogenic activity (mimicking the effects of estrogens), while surface water exhibited anti-estrogenic and anti-androgenic activities, similar to the chemicals we tested. (more…)