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Concept: Luteinizing hormone

200

Women have elevated rates of thyroid disease compared to men. Environmental toxicants have been implicated as contributors to this dimorphism, including polybrominated diphenyl ethers (PBDEs), flame retardant chemicals that disrupt thyroid hormone action. PBDEs have also been implicated in the disruption of estrogenic activity, and estrogen levels regulate thyroid hormones. Post-menopausal women may therefore be particularly vulnerable to PBDE induced thyroid effects, given low estrogen reserves. The objective of this study was to test for an association between serum PBDE concentrations and thyroid disease in women from the United States (U.S.), stratified by menopause status.

Concepts: Hormone replacement therapy, Hormone, Menopause, Estrogen, Luteinizing hormone, Thyroid hormone, Flame retardant, Flame retardants

188

Menopausal hormone therapy (MHT) reportedly increases the risk of cognitive decline in women over age 65 y. It is unknown whether similar risks exist for recently postmenopausal women, and whether MHT affects mood in younger women. The ancillary Cognitive and Affective Study (KEEPS-Cog) of the Kronos Early Estrogen Prevention Study (KEEPS) examined the effects of up to 4 y of MHT on cognition and mood in recently postmenopausal women.

Concepts: Osteoporosis, Hormone replacement therapy, Decision making, Hormone, Menopause, Estrogen, Luteinizing hormone, Cognition

174

Previous research has documented shifts in women’s attractions to their romantic partner and to men other than their partner across the ovulation cycle, contingent on the degree to which her partner displays hypothesized indicators of high-fitness genes. The current study set out to replicate and extend this finding. Forty-one couples in which the woman was naturally cycling participated. Female partners reported their feelings of in-pair attraction and extra-pair attraction on two occasions, once on a low-fertility day of the cycle and once on a high-fertility day of the cycle just prior to ovulation. Ovulation was confirmed using luteinizing hormone tests. We collected two measures of male partner sexual attractiveness. First, the women in the study rated their partner’s sexual attractiveness. Second, we photographed the partners and had the photos independently rated for attractiveness. Shifts in women’s in-pair attractions across the cycle were significantly moderated by women’s ratings of partner sexual attractiveness, such that the less sexually attractive women rated their partner, the less in-pair attraction they reported at high fertility compared with low fertility (partial r = .37, p(dir) = .01). Shifts in women’s extra-pair attractions across the cycle were significantly moderated by third-party ratings of partner attractiveness, such that the less attractive the partner was, the more extra-pair attraction women reported at high relative to low fertility (partial r = -.33, p(dir) = .03). In line with previous findings, we found support for the hypothesis that the degree to which a woman’s romantic partner displays indicators of high-fitness genes affects women’s attractions to their own partner and other men at high fertility.

Concepts: Sexual intercourse, Estrogen, Luteinizing hormone, Menstrual cycle, Woman, Ovulation, Sexuality, Physical attractiveness

172

Volumes of paracardial adipose tissue (PAT) and epicardial adipose tissue (EAT) are greater after menopause. Interestingly, PAT but not EAT is associated with estradiol decline, suggesting a potential role of menopause in PAT accumulation. We assessed whether volumes of heart fat depot (EAT and PAT) were associated with coronary artery calcification (CAC) in women at midlife and whether these associations were modified by menopausal status and estradiol levels.

Concepts: Hormone replacement therapy, Coronary artery disease, Middle age, Heart, Menopause, Estrogen, Luteinizing hormone, Menstrual cycle

166

A controlled release delivery system helps to overcome the problem of short life of the leutinizing hormone releasing hormone (LHRH) in blood and avoids use of multiple injections to enhance reproductive efficacy. Chitosan- and chitosan-gold nanoconjugates of salmon LHRH of desired size, dispersity and zeta potential were synthesized and evaluated at half the dose rate against full dose of bare LHRH for their reproductive efficacy in the female fish, Whereas injections of both the nanoconjugates induced controlled and sustained surge of the hormones with peak (P<0.01) at 24 hrs, surge due to bare LHRH reached its peak at 7 hrs and either remained at plateau or sharply declined thereafter. While the percentage of relative total eggs produced by fish were 130 and 67 per cent higher, that of fertilised eggs were 171 and 88 per cent higher on chitosan- and chitosan-gold nanoconjugates than bare LHRH. Chitosan nanoconjugates had a 13 per cent higher and chitosan gold preparation had a 9 per cent higher fertilization rate than bare LHRH. Histology of the ovaries also attested the pronounced effect of nanoparticles on reproductive output. This is the first report on use of chitosan-conjugated nanodelivery of gonadotropic hormone in fish.

Concepts: Hormone, Menopause, Luteinizing hormone, Estradiol, Follicle-stimulating hormone, Human chorionic gonadotropin, Gonadotropin, Hormones

157

Astragalus membranaceus (AM) is a Chinese traditional herb which has been reported to have broad positive effects on many diseases, including hepatitis, heart disease, diabetes and skin disease. AM can promote cell proliferation, increase the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), and inhibit apoptosis by regulating the transcription of proto-oncogenes controlling cell death. While AM is included in some commercially available “testosterone boosting supplements”, studies directly testing ability of AM to modulate testosterone production are lacking. In the present study, we examined the effects of AM on Leydig cell function in vitro.

Concepts: Cancer, Death, Luteinizing hormone, Superoxide dismutase, Testosterone, Sertoli cell, Puberty, Leydig cell

73

Although many studies indicate the interplay of genetic and environmental factors in the etiology of autism spectrum disorder (ASD), our limited understanding of the underlying mechanisms hampers the development of effective ways of detecting and preventing the disorder. Recent studies support the hypothesis that prenatal androgen exposure contributes to the development of ASD. This would suggest that maternal polycystic ovary syndrome (PCOS), a condition associated with excess androgens, would increase the risk of ASD in the offspring. We conducted a matched case-control study nested within the total population of Sweden (children aged 4-17 who were born in Sweden from 1984 to 2007). The sample consisted of 23 748 ASD cases and 208 796 controls, matched by birth month and year, sex and region of birth. PCOS and ASD were defined from ICD codes through linkage to health-care registers. Maternal PCOS increased the odds of ASD in the offspring by 59%, after adjustment for confounders (odds ratio (OR) 1.59, 95% confidence interval (CI) 1.34-1.88). The odds of offspring ASD were further increased among mothers with both PCOS and obesity, a condition common to PCOS that is related to more severe hyperandrogenemia (OR 2.13, 95% CI 1.46-3.10). Risk estimates did not differ between sexes. In conclusion, children of women with PCOS appear to have a higher risk of developing ASD. This finding awaits confirmation, and exploration of potentially underlying mechanisms, including the role of sex steroids in the etiology of ASD.Molecular Psychiatry advance online publication, 8 December 2015; doi:10.1038/mp.2015.183.

Concepts: Luteinizing hormone, Autism, Pervasive developmental disorder, Metformin, Asperger syndrome, Autism spectrum, PDD-NOS, Polycystic ovary syndrome

38

DESCRIPTION: Update of the 2005 U.S. Preventive Services Task Force (USPSTF) recommendation statement on hormone therapy for the prevention of chronic conditions in postmenopausal women. METHODS: The USPSTF commissioned a review of the literature to update evidence about the benefits and harms of using menopausal hormone therapy to prevent chronic conditions, as well as whether the benefits and harms of hormone therapy differ by population subgroups defined by age; the presence of comorbid medical conditions; and the type, dose, and method of hormonal delivery. POPULATION: This recommendation applies to postmenopausal women who are considering hormone therapy for the primary prevention of chronic medical conditions. It does not apply to women who are considering hormone therapy for the management of menopausal symptoms, such as hot flashes or vaginal dryness. It also does not apply to women younger than 50 years who have had surgical menopause. RECOMMENDATION: The USPSTF recommends against the use of combined estrogen and progestin for the prevention of chronic conditions in postmenopausal women. (Grade D recommendation)The USPSTF recommends against the use of estrogen for the prevention of chronic conditions in postmenopausal women who have had a hysterectomy. (Grade D recommendation).

Concepts: Osteoporosis, Hormone replacement therapy, Medicine, Hormone, Menopause, Estrogen, Endocrinology, Luteinizing hormone

35

Alcohol (ethanol) and resistance exercise can independently affect circulating bioavailable testosterone concentration. PURPOSE: The purpose of this study was to examine the testosterone bioavailability and the anabolic endocrine milieu in response to acute ethanol ingestion following a bout of heavy resistance exercise. METHODS: Eight resistance trained men (mean ± SD: 25.3 ± 3.2 yrs, 87.7 ± 15.1 kg, 177 ± 7 cm) completed two identical acute heavy resistance exercise tests (AHRET: six sets of 10 repetitions of Smith machine squats) separated by 1 week. Post-AHRET participants consumed either 1.086 g of grain ethanol per kg lean mass (EtOH condition) or no ethanol (Placebo condition). Blood samples were collected immediately before exercise (PRE), immediately after exercise (IP), and every 20 min postexercise for 300 min. Samples following IP were pooled into phases (20-40 min, 60-120 min, and 140-300 min after exercise) and analyzed for total (TT) and free testosterone (FT), sex hormone binding globulin (SHBG), cortisol, and estradiol. RESULTS: Peak blood ethanol concentration (0.088 ± 0.015 g·dl) was achieved 60-90 min post-exercise. TT and FT was elevated significantly (p≤0.05) at IP for both conditions. At 140-300 min post-exercise TT, FT, and free androgen index were significantly higher for EtOH (TT: 22.5 ± 12.5 nmol·l ; FT: 40.5 ± 7.6 pmol·l) than for Placebo (TT: 13.9 ± 6.8 nmol·l; FT: 22.7 ± 10.0 pmol·l). No differences between conditions were noted for SHBG, Cortisol, or Estradiol. CONCLUSION: Post-exercise ethanol ingestion affects the hormonal milieu including testosterone concentration and bioavailability during recovery from resistance exercise.

Concepts: Hormone, Ethanol, Luteinizing hormone, Testosterone, Sex hormone-binding globulin, Estradiol, Adrenal cortex, Anabolic steroid

29

Objective:To investigate the influence of adiposity on patterns of sex hormones across the menstrual cycle among regularly menstruating women.Subjects:The BioCycle Study followed 239 healthy women for 1-2 menstrual cycles, with up to eight visits per cycle timed using fertility monitors.Methods:Serum estradiol (E2), progesterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and sex hormone-binding globulin (SHBG) were measured at each visit. Adiposity was measured by anthropometry and by dual energy X-ray absorptiometry (DXA). Differences in hormonal patterns by adiposity measures were estimated using nonlinear mixed models, which allow for comparisons in overall mean levels, amplitude (i.e., lowest to highest level within each cycle) and shifts in timing of peaks while adjusting for age, race, energy intake and physical activity.Results:Compared with normal weight women (n=154), obese women (body mass index (BMI) 30 kg m(-2), n=25) averaged lower levels of progesterone (-15%, P=0.003), LH (-17%, P=0.01), FSH (-23%, P=0.001) and higher free E2 (+22%, P=0.0001) across the cycle. To lesser magnitudes, overweight women (BMI: 25-30, n=60) also exhibited differences in the same directions for mean levels of free E2, FSH and LH. Obese women experienced greater changes in amplitude of LH (9%, P=0.002) and FSH (8%, P=0.004), but no differences were observed among overweight women. Higher central adiposity by top compared to bottom tertile of trunk-to-leg fat ratio by DXA was associated with lower total E2 (-14%, P=0.005), and FSH (-15%, P=0.001). Peaks in FSH and LH occurred later (∼0.5 day) in the cycle among women with greater central adiposity.Conclusion:Greater total and central adiposity were associated with changes in mean hormone levels. The greater amplitudes observed among obese women suggest compensatory mechanisms at work to maintain hormonal homeostasis. Central adiposity may be more important in influencing timing of hormonal peaks than total adiposity.

Concepts: Obesity, Menopause, Estrogen, Luteinizing hormone, Body mass index, Estradiol, Menstrual cycle, Follicle-stimulating hormone