No effect of supplemented heat stress during an acute endurance exercise session in hypoxia on hepcidin regulation.

Hepcidin is a novel factor for iron deficiency in athletes, which is suggested to be regulated by interleukin-6 (IL-6) or erythropoietin (EPO). PURPOSE: The purpose of the present study was to compare endurance exercise-induced hepcidin elevation among "normoxia", "hypoxia" and "combined heat and hypoxia". METHODS: Twelve males (21.5 ± 0.3 years, 168.1 ± 1.2 cm, 63.6 ± 2.0 kg) participated in the present study. They performed 60 min of cycling at 60% of [Formula: see text] in either "heat and hypoxia" (HHYP; FiO2 14.5%, 32 °C), "hypoxia" (HYP; FiO2 14.5%, 23 °C) or "normoxia" (NOR; FiO2 20.9%, 23 °C). After completing the exercise, participants remained in the prescribed conditions for 3 h post-exercise. Blood samples were collected before, immediately and 3 h after exercise. RESULTS: Plasma IL-6 level significantly increased immediately after exercise (P < 0.05), with no significant difference among the trials. A significant elevation in serum EPO was observed 3 h after exercise in hypoxic trials (HHYP and HYP, P < 0.05), with no significant difference between HHYP and HYP. Serum hepcidin level increased 3 h after exercise in all trials (NOR, before 18.3 ± 3.9 and post180 31.2 ± 6.3 ng/mL; HYP, before 13.5 ± 2.5 and post180 23.3 ± 3.6 ng/mL, HHYP; before 15.8 ± 3.3 and post180 31.4 ± 5.3 ng/mL, P < 0.05). However, there was no significant difference among the trials during post-exercise. CONCLUSION: Endurance exercise in "combined heat and hypoxia" did not exacerbate exercise-induced hepcidin elevation compared with the same exercise in "hypoxia" or "normoxia".

A Sexually Dimorphic Area of the Dorsal Hypothalamus in Mice and Common Marmosets.

We found a novel sexually dimorphic area (SDA) in the dorsal hypothalamus (DH) of mice. The SDA-DH was sandwiched between 2 known male-biased sexually dimorphic nuclei, the principal nucleus of the bed nucleus of the stria terminalis and the calbindin-sexually dimorphic nucleus, and exhibited a female-biased sex difference in neuronal cell density. The density of neurons in the SDA-DH was increased in male mice by orchidectomy on the day of birth and decreased in female mice by treatment with testosterone, dihydrotestosterone, or estradiol within 5 days after birth. These findings indicate that the SDA-DH is defeminized under the influence of testicular testosterone, which acts via both directly by binding to the androgen receptor, and indirectly by binding to the estrogen receptor after aromatization. We measured the activity of SDA-DH neurons with c-Fos, a neuronal activity marker, in female mice during maternal and sexual behaviors. The number of c-Fos-expressing neurons in the SDA-DH of female mice was negatively correlated with maternal behavior performance. However, the number of c-Fos-expressing neurons did not change during female sexual behavior. These findings suggest that the SDA-DH contains a neuronal cell population, the activity of which decreases in females exhibiting higher performance of maternal behavior, but it may contribute less to female sexual behavior. Additionally, we examined the brain of common marmosets and found an area that appears to be homologous with the mouse SDA-DH. The sexually dimorphic structure identified in this study is not specific to mice and may be found in other species.

Sex differences in cells expressing green fluorescent protein under the control of the estrogen receptor-α promoter in the hypothalamus of mice.

Estradiol that originates from testicular testosterone and binds to estrogen receptor-α (ERα) during developing period acts to organize the male-type brain in mice. Here, we examined transgenic mice expressing green fluorescent protein (GFP) under the control of the ERα promoter, in which ERα-expressing cells in the brain can be visualized by GFP. Fluorescence microscopy revealed the existence of many GFP-expressing cells in the medial preoptic area, medial preoptic nucleus (MPN), bed nucleus of the stria terminalis (BNST), and striohypothalamic nucleus (StHy) of adult transgenic mice. Neuronal nuclear antigen, a neuron marker, but not glial fibrillary acidic protein, an astrocyte marker, was mostly expressed by GFP-expressing cells. Analysis of GFP expression area showed that adult females had higher GFP expression in a region including the ventral part of the BNST, StHy, and dorsal part of the MPN than in adult males. Such female-biased sex difference was also found in transgenic pups on postnatal day 5 and 8. The GFP expression area of adult females was decreased by postnatal treatment with testosterone or estradiol. These results indicate that GFP visualizes a sex difference of ERα-expressing neurons. The transgenic mice may be useful for the analysis of the sexual differentiation of the brain.

How Can We Link General Medical and Behavioral Health Care? International Models for Practice and Policy.

A range of integration models for providing effective care to individuals with comorbid general medical and behavioral health conditions have been described and tested in varied settings internationally for several subsets of this population. This column examines models in three countries selected to showcase implementation in a variety of health systems: the national health system in England, nationally regulated individual insurance market in the Netherlands, and a mixture of employer-sponsored and government-funded health insurance plans in Japan. The authors describe a set of key practices for and challenges to the successful implementation of these models.