EVIDENCE FOR ENDOCRINE DISRUPTING EFFECTS OF LEAD ON TELEOST CIRRHINUS MRIGALA

Lead is one of the elements that can be described as purely toxic. Lead displaces biologically important metals interfering with a variety of body's chemical reactions. A variety of environmental contaminants including heavy metals interfere the endocrine axis of fish. Lead is reported with endocrine disruptive potential. Lead affects the hypothalamus pituitary gonadal axis at multiple sites. In the present work an effort is made to explore qualitative changes in the pituitary gland cell types of Cirrhinus mrigala after an acute and chronic exposure to lead. The study revealed the toxic effects of lead on endocrine functions of a teleost which further affects the fecundity of fish. The present study provides a manifold confirmation on the endocrine disrupting effects of lead in fish

Determination of Annual Plasma Hormone Levels Associated with Reproduction in Long-Day Breeding Domestic Geese

This paper examines the dynamics of circulating hormone changes connected with reproduction in geese during the annual period related to gonad morphometry. One hundred geese were examined. The levels of prolactin (PRL), triiodothyronine (T3), thyroxine (T4), testosterone (T), progesterone (P4) and estradiol (E2) were estimated. In both sexes, PRL level patterns fit a quadratic trend with elevations in the post-breeding and the second half of the breeding–laying periods. During these periods, differences in the PRL level between sexes were noted. In ganders, increased PRL levels during the laying period occurred earlier compared to in female geese. Cubic trends for T and E2 in ganders and quadratic for T, P4, and E2 in female geese were observed. PRL was negatively correlated with T in both sexes and with P4 and E2 in female geese. A higher level of T3 and variation in T4 in ganders with a quartic trend in ganders vs. a quadratic in female geese were noted. Patterns of PRL, T, and E2 suggested that the breeding–laying period in ganders may be shorter than in female geese. These findings will be used to explore experimental manipulations of the endocrine axis to increase synchronisation of both sexes.

Transcriptome Analysis Reveals the Endocrine Regulation on the Expression of IAG in Litopenaeus vannamei

The insulin-like androgenic gland hormone (IAG) plays a key role in male sexual differentiation and spermatogenesis in crustaceans. The expression of IAG is usually negatively regulated by neuropeptide hormones through the “eyestalk-AG” endocrine axis. However, the underlying mechanism is still largely unknown. In the present study, we performed a comparative transcriptome analysis on the androgenic gland (AG), the main secretory organ of IAG, of L. vannamei before and after unilateral eyestalk ablation. A total of 67 differentially expressed genes (DEGs) were identified, including some putative genes involved in sexual development. Interestingly, several genes related to molting and endocrine processes were found differentially expressed between the two treatments. Further investigation on the expression profiles of these genes and Lv-IAG showed that their expression patterns were closely correlated throughout the molting cycle. In addition, injection of 20-hydroxyecdysone (20E) could inhibit the expression of Lv-IAG at different molting stages in a dosage-dependent manner. The data indicated that ecdysteroids played important roles in regulating the Lv-IAG expression and might bridge the endocrine axis between eyestalk and AG. The present study provided new insights into understanding the regulation of sexual development in male crustacean.

Protective Role of Galanin during Chemically Induced Inflammation in Zebrafish Larvae

During a pathological condition, many different systems are involved in the response of an affected organism. Galanin is considered to be a neuropeptide that plays an important role in the central nervous system; however, it is involved in many other biological processes, including the immune response. During our studies, we showed that galanin became upregulated in zebrafish larvae when exposed to copper sulfate. Moreover, the presence of normal levels of galanin, administration of a galanin analog NAX 5055 or galanin overexpression led to lowered lateral line damage and enhanced expression of inflammatory markers compared to the knockout larvae. The results showed that the neuroendocrine system acts multifunctionally and should be considered as a part of the complex neuro–immune–endocrine axis.

OR11-01 Using Kisspeptin to Predict Pubertal Outcomes for Youth With Pubertal Delay

Background: The management of youth presenting with delayed puberty is challenging because it can be difficult to predict which children will eventually progress through puberty and which children will not. We have previously shown that exogenous administration of the neuropeptide kisspeptin, which stimulates GnRH release, can be used to probe the integrity of the reproductive endocrine axis. We hypothesized that responses to kisspeptin could predict outcomes for individuals with pubertal delay. Methods: We conducted a longitudinal study of 16 children (3 girls and 13 boys) with delayed or stalled puberty who had undergone stimulation testing with kisspeptin and GnRH. Participants were followed with serial physical examinations and laboratory studies every six months for evidence of progression through puberty. Inhibin B was measured in boys. A subset of participants underwent exome sequencing. Results: “Kisspeptin responders” who had responded to kisspeptin with a rise in LH of 0.8 mIU/mL or greater all subsequently progressed through puberty (n = 8). In contrast, “kisspeptin nonresponders” who had exhibited LH responses to kisspeptin ≤0.4 mIU/mL all reached age 18 years without developing physical signs of puberty (n = 8). Thus, responses to kisspeptin accurately predicted later pubertal outcomes (p = 0.0002), with sensitivity and specificity of 100% (95% CI 74-100%). Moreover, the kisspeptin-stimulation test outperformed overnight LH measurements, GnRH-stimulated LH, inhibin B, and genetic testing in predicting pubertal outcomes. Conclusion: The kisspeptin-stimulation test can be used to reveal future reproductive endocrine potential in prepubertal children and is a promising novel tool for predicting pubertal outcomes for children with delayed puberty. Trial registration: ClinicalTrials.gov NCT01438034

Hormonal Profiles of Menstrual Bleeding Patterns During the Luteal-Follicular Transition

Context Menstrual cycle function is determined by a complex endocrine axis that controls the ovaries and endometrium. While the late luteal phase is characterized by declining progesterone and estrogen, how these hormonal profiles relate to menstrual bleeding patterns is not well understood. Objective Characterize associations between luteal phase hormonal profiles and subsequent menstrual bleeding patterns, specifically spotting before bleeding. Design, Setting, and Participants We examined creatinine-adjusted urinary estrone 3-glucuronide (E13G) and pregnanediol 3-glucuronide (Pd3G) levels in relation to spotting in 116 premenopausal women (ages 20–47) who kept daily menstrual diaries and collected first morning urine samples for ≥ 2 consecutive cycles or 1 luteal-follicular transition (n = 283 transitions). We used linear mixed models to estimate associations between luteal phase hormone levels and spotting before bleeding. Main Outcome Measure(s) and Results Transitions with ≥ 1 days of spotting before menstrual bleeding (n = 118) had greater luteal phase Pd3G levels vs nonspotting transitions (n = 165). Differences in Pd3G between spotting and nonspotting transitions were largest at menses onset (34.8%, 95% confidence interval, 18.9%, 52.7%). Pd3G levels for spotting transitions dropped to similar levels as nonspotting transitions an average of 1 day later, which aligned with the first day of bleeding for transitions with contiguous spotting. Spotting transitions were preceded by slower rates of Pd3G decline than nonspotting transitions, whereas E13G declines were similar. Conclusions Self-reported bleeding patterns may provide insight into luteal phase Pd3G levels. First bleed appears to be the best choice for defining the end of the luteal phase and achieving hormonal consistency across transitions.