Obesity is a heritable disorder, with children of obese fathers at higher risk of developing obesity. Environmental factors epigenetically influence somatic tissues, but the contribution of these factors to the establishment of epigenetic patterns in human gametes is unknown. Here, we hypothesized that weight loss remodels the epigenetic signature of spermatozoa in human obesity. Comprehensive profiling of the epigenome of sperm from lean and obese men showed similar histone positioning, but small non-coding RNA expression and DNA methylation patterns were markedly different. In a separate cohort of morbidly obese men, surgery-induced weight loss was associated with a dramatic remodeling of sperm DNA methylation, notably at genetic locations implicated in the central control of appetite. Our data provide evidence that the epigenome of human spermatozoa dynamically changes under environmental pressure and offers insight into how obesity may propagate metabolic dysfunction to the next generation.
A total of 1,215 young Danish men aged 18-28 years were recruited between 2008 and 2012 when they attended a compulsory medical examination to determine their fitness for military service. The participants delivered a semen sample, had a blood sample drawn, and underwent a physical examination. They responded to questionnaires including information on marijuana and recreational drug use during the past 3 months (no use, use once per week or less, or use more than once per week). A total of 45% had smoked marijuana within the last 3 months. Regular marijuana smoking more than once per week was associated with a 28% (95% confidence interval (CI): -48, -1) lower sperm concentration and a 29% (95% CI: -46, -1) lower total sperm count after adjustment for confounders. The combined use of marijuana more than once per week and other recreational drugs reduced the sperm concentration by 52% (95% CI: -68, -27) and total sperm count by 55% (95% CI: -71, -31). Marijuana smokers had higher levels of testosterone within the same range as cigarette smokers. Our findings are of public interest as marijuana use is common and may be contributing to recent reports of poor semen quality.
Background: Gynecomastia (GM) is a benign proliferation of the glandular tissue of the breast in men. It is a frequent condition with a reported prevalence of 32-65%, depending on the age and the criteria used for definition. GM of infancy and puberty are common, benign conditions resolving spontaneously in the majority of cases. GM of adulthood is more prevalent among the elderly and proper investigation may reveal an underlying pathology in 45-50% of cases. Objectives: The aim was to provide clinical practice guidelines for the evaluation and management of GM. Materials and methods: A literature search of articles in English for the term 'gynecomastia' was conducted. Evidence-based recommendations were developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system. Results: A set of five statements and fifteen clinical recommendations was formulated. Conclusions: The purpose of GM assessment should be the detection of underlying pathological conditions, reversible causes (administration/abuse of aggravating substances), and the discrimination from other breast lumps, particularly breast cancer. Assessment should comprise a thorough medical history and physical examination of the breast and genitalia (including testicular ultrasound). A set of laboratory investigations may integrate the evaluation: testosterone (T), estradiol (E2), sex hormone-binding globulin (SHBG), luteinizing hormone (LH), follicular stimulating hormone (FSH), thyroid stimulating hormone (TSH), prolactin, human chorionic gonadotropin (hCG), alpha-fetal protein (AFP), liver and renal function tests. Breast imaging may be used whenever the clinical examination is equivocal. In suspicious lesions, core needle biopsy should be sought directly instead. Watchful waiting is recommended after treatment of underlying pathology or discontinuation of substances associated with GM. T treatment should be offered to men with proven T deficiency. The use of selective estrogen receptor modulators (SERMs), aromatase inhibitors (AIs) and non-aromatizable androgens is not justified in general. Surgical treatment is the therapy of choice for patients with long-lasting GM.
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