Vaccine-induced immunity declines with age, which may differ between males and females. Using human sera collected before and 21 days after receipt of the monovalent A/Cal/09 H1N1 vaccine, we evaluated cytokine and antibody responses in adult (18-45 years) and aged (65+ years) individuals. After vaccination, adult females developed greater IL-6 and antibody responses than either adult males or aged females, with female antibody responses being positively associated with concentrations of estradiol. To test whether protection against influenza virus challenge was greater in females than males, we primed and boosted adult (8-10 weeks) and aged (68-70 weeks) male and female mice with an inactivated A/Cal/09 H1N1 vaccine or no vaccine and challenged with a drift variant A/Cal/09 virus. As compared with unvaccinated mice, vaccinated adult, but not aged, mice experienced less morbidity and better pulmonary viral clearance following challenge, regardless of sex. Vaccinated adult female mice developed antibody responses that were of greater quantity and quality and more protective than vaccinated adult males. Sex differences in vaccine efficacy diminished with age in mice. To determine the role of sex steroids in vaccine-induced immune responses, adult mice were gonadectomized and hormones (estradiol in females and testosterone in males) were replaced in subsets of animals before vaccination. Vaccine-induced antibody responses were increased in females by estradiol and decreased in males by testosterone. The benefit of elevated estradiol on antibody responses and protection against influenza in females is diminished with age in both mice and humans.

Age-associated changes in the impact of sex steroids on influenza vaccine responses in males and females

Rapid steroid hormone actions via membrane receptors.

BACKGROUND Infertility is a condition of the reproductive system that affects ∼10-15% of couples attempting to conceive a baby. More than half of all cases of infertility are a result of female conditions, while the remaining cases can be attributed to male factors, or to a combination of both. The search for suitable biomarkers of pregnancy outcome is a challenging issue in human reproduction, aimed at identifying molecules with predictive significance of the reproductive potential of male and female gametes. Among the various candidates, endocannabinoids (eCBs), and in particular anandamide (AEA), represent potential biomarkers of human fertility disturbances. Any perturbation of the balance between synthesis and degradation of eCBs will result in local changes of their tone in human female and male reproductive tracts, which in turn regulates various pathophysiological processes, oocyte and sperm maturation included. METHODS PubMed and Web of Science databases were searched for papers using relevant keywords like 'biomarker', 'endocannabinoid', 'infertility', 'pregnancy' and 'reproduction'. RESULTS In this review, we discuss different studies on the measurements of AEA and related eCBs in human reproductive cells, tissues and fluids, where the local contribution of these bioactive lipids could be critical in ensuring normal sperm fertilizing ability and pregnancy. CONCLUSION Based on the available data, we suggest that the AEA tone has the potential to be exploited as a novel diagnostic biomarker of infertility, to be used in association with assays of conventional hormones (e.g. progesterone, β-chorionic gonadotrophin) and semen analysis. However further quantitative research of its predictive capacity is required.

/pdf/endocannabinoids-as-biomarkers-of-human-reproduction-2o76epgqra.pdf

Endocannabinoids as biomarkers of human reproduction

Background:Correlated data are ubiquitous in epidemiologic research, particularly in nutritional and environmental epidemiology where mixtures of factors are often studied. Our objectives are to demonstrate how highly correlated data arise in epidemiologic research and provide guidance, using a dire

/pdf/collinearity-and-causal-diagrams-a-lesson-on-the-importance-3jtwjz41b7.pdf

Collinearity and Causal Diagrams: A Lesson on the Importance of Model Specification.

The central nervous system receives hormonal cues (e.g., estrogens and leptin, among others) that influence reproduction and energy homeostasis. 17β-estradiol (E2) is known to regulate gonadotropin-releasing hormone (GnRH) secretion via classical steroid signaling and rapid non-classical membrane-initiated signaling. Because GnRH neurons are void of leptin receptors, the actions of leptin on these neurons must be indirect. Although it is clear that the arcuate nucleus of the hypothalamus is the primary site of overlap between these two systems, it is still unclear which neural network(s) participate in the cross-talk of E2 and leptin, two hormones essential for reproductive function and metabolism. Herein we review the progress made in understanding the interactions between reproduction and energy homeostasis by focusing on the advances made to understand the cellular signaling of E2 and leptin on three neural networks: kisspeptin, pro-opiomelanocortin (POMC) and neuropeptide Y (NPY). Although critical in mediating the actions of E2 and leptin, considerable work still remains to uncover how these neural networks interact in vivo.

/pdf/cross-talk-between-reproduction-and-energy-homeostasis-21xubpqagn.pdf

Cross-talk between reproduction and energy homeostasis: central impact of estrogens, leptin and kisspeptin signaling.

Background: It is established that serum level of leptin is affected by transitional phases of reproduction. It is also reported that the puberty is triggered when body fat and circulating levels of leptin exceed the critical thresholds, butthere is less focus on the serum level of leptin and its relationship with different phases of menstrual cycle and the fertility. Objectives: The present study try to determines the serum concentration of leptin and fertility hormonesin the various phases of normal menstrual cycle of fertile women and compare any difference in serum concentration between age groups of 18-30 years and 31-41 years It is a well known fact that fertility start to decrease from age 31 years. Patients and Methods: A total of 118 healthy fertile women with normal menstrual cycle aged between 18-40, were divided into two age groups (n = 65) 18-30 years and (n = 53) 31-40 years. Serum concentrations of leptin, estradiol, progesterone, luteinising hormone (LH) and follicle-stimulating hormone (FSH) were measured on day1 (menstrual phase), day7 (proliferative/follicular phase), day14 (ovulatory phase), day21 (luteal phase) and day 28(secretory phase) of the menstrual cycle. Results: There was a significant increase (P < 0.05) in leptin levels on day 14 (12.75 + 5.8 ng/mL) and day 21 (12.91 + 3.2 ng/mL) for age group 18-30 years compared to day 14 (11.60 + 3.2 ng/mL) and day 21 (11.60 + 3.2 ng/mL) for age group 31-40 years. Leptin was positively correlated with FSH on day 14, with LH on day 7 and day 21; likewise, with progesterone on day 21 and day 28 and with estradiol on day 7 and day 14 for both age groups. Conclusions: The serum leptin level was at the lowest level during the menstrual and secretory phase and the highest level was around the luteal phase. The significant increase ofleptin in the younger age group raise this question whether circulating leptin has any role to play in the age of pregnancy and fertility. Data in this study shows that leptin level was affected with increase in age; therefore changes in leptin level will affect fertility in this study suggest that there may be a relation between leptin levels and fertility.

Olawole Micheal Ajala

Papers

Changes in serum leptin during phases of menstrual cycle of fertile women: relationship to age groups and fertility