Adrenopause or decline of serum adrenal androgens with age in women living at sea level or at high altitude.

The present study aimed to determine adrenopause or reduction of serum adrenal androgens with age at high altitude and at sea level. It was a cross-sectional study performed in 210 women resident at high altitude (4340 m) and 123 women living in Lima (150 m), aged 20-70 years. Fasting early morning blood samples were obtained. Serum dehydroepiandrosterone (DHEA), DHEA sulphate (DHEAS), androstenedione, testosterone and estradiol were measured by radioimmunoassay. Serum testosterone concentrations were greater in women living at high altitude than in those resident at sea level. Serum concentrations of DHEA, DHEAS and androstenedione were lower in women living at high altitude than in those living at sea level. The DHEAS/DHEA ratio was significantly greater, and the androstenedione/testosterone ratio was lower in samples from women living at high altitude. Among women older than 50 years of age, a greater decline in serum concentrations of DHEA was observed in those living at high altitude than in those living at sea level. Among women 60-70 years of age, serum concentrations of DHEA at high altitude were 46.9% of those in women of the same age living at sea level. Decay of DHEAS at sea level and at high altitude occurred from the age of 40 years. The decline was faster at high altitude than at sea level, and in women aged 60-70 years serum values of DHEAS at high altitude were 56% of those at sea level. In the same age group, serum concentrations of androstenedione among those native to high altitudes were 27.34% of the value at sea level. At sea level, serum testosterone concentrations did not change with age from 20 to 70 years. In women aged 20-39 years and 50-59 years, serum testosterone concentrations were greater at high altitude than at sea level (P<0.05). In those aged 60-70 years, the concentrations were similar in those living at sea level and at high altitude. At sea level and at high altitude, the serum testosterone/estradiol ratio increased with age (P<0.0034 and P<0.0001 respectively). This ratio increased at an earlier age among those living at high altitude (40-49 years) than among those living at sea level (50-59 years). Multivariate analysis showed that altitude (P<0.0001) and greater chronological age (P<0.001) were associated with lower serum DHEAS concentrations. DHEAS was related to chronological age (P<0.0001). Low serum androstenedione concentrations were related to living at high altitude at birth and greater chronological age (P<0.0001). In conclusion, adrenopause is attained earlier and is of greater magnitude at high altitude than at sea level.

Serum levels of adrenal androgens up to adrenarche in Peruvian children living at sea level and at high altitude.

Serum levels of adrenal androgens were measured in children of both sexes living at sea level and at high altitude using a cross-sectional design. The levels were compared in relation to age at each altitude (150 m and 3400 m above sea level), and the first significant increase in mean levels compared with values at preceding ages was assessed and defined as adrenarche. A total of 118 boys and 95 girls aged 6-12 years living at low altitude and 95 boys and 104 girls aged 7-15 years living at high altitude, all of them attending public schools, were studied. Serum dehydroepiandrosterone, dehydroepiandrosterone sulphate and androstenedione were measured by radioimmunoassay and height and weight by standard anthropometric techniques. There were two significant increases in serum levels of adrenal androgens, the first observed in children between 6 and 8 years at sea level, and between 7 and 9 years at high altitude, and the second in children between 10 and 12 years at sea level and between 12 and 15 years at high altitude. Serum adrenal androgen levels increased earlier in children at sea level than at high altitude. It is concluded that adrenarche occurs later at high altitude than at sea level.

Effect of Lepidium meyenii (Maca), a root with aphrodisiac and fertility-enhancing properties, on serum reproductive hormone levels in adult healthy men.

Lepidium meyenii (Maca) is a Peruvian hypocotyl that grows exclusively between 4000 and 4500 m in the central Andes. Maca is traditionally employed in the Andean region for its supposed aphrodisiac and/or fertility-enhancing properties. This study was a 12-week double-blind, placebo-controlled, randomized, parallel trial in which active treatment with different doses of Maca Gelatinizada was compared with a placebo. The study aimed to test the hypothesis that Maca has no effect on serum reproductive hormone levels in apparently healthy men when administered in doses used for aphrodisiac and/or fertility-enhancing properties. Men aged between 21 and 56 Years received 1500 mg or 3000 mg Maca. Serum levels of luteinizing hormone, follicle-stimulating hormone, prolactin, 17-alpha hydroxyprogesterone, testosterone and 17-beta estradiol were measured before and at 2, 4, 8 and 12 weeks of treatment with placebo or Maca (1.5 g or 3.0 g per day). Data showed that compared with placebo Maca had no effect on any of the hormones studied nor did the hormones show any changes over time. Multiple regression analysis showed that serum testosterone levels were not affected by treatment with Maca at any of the times studied (P, not significant). In conclusion, treatment with Maca does not affect serum reproductive hormone levels.

Hormone profile during the menstrual cycle at high altitude.

OBJECTIVES: To determine the hormone profile during the menstrual cycle in women at sea level and at high altitude, and whether the time between the gonadotropin peak and ovulation is different at high altitude from that at sea level. METHODS: The study was carried out in Lima (150 m) and Cerro de Pasco (4340 m), Peru. The hormone profile of 10 adult regularly menstruating women at sea level and 10 women at high altitude was assessed. Ovulation was identified by vaginal ultrasonography. RESULTS: The pre-ovulatory follicle diameter was lower (P < 0.001) at high altitude than at sea level. Ovulation after LH peak occurred earlier at high altitude than at sea level. Serum FSH levels were higher at late luteal phase and early follicular phase at high altitude than at sea level (P < 0.05). The serum LH and FSH peaks were similar in women at sea level and at high altitude. During the early follicular phase serum estradiol levels were significantly higher at high altitude than at sea level (P < 0.05). During the late follicular phase the production of estradiol was higher at sea level than at high altitude (P < 0.05). The peak of serum estradiol was at day -1 in Lima and in day 0 at high altitude. At ovulation, the serum estradiol levels in women at sea level were 55.1% of the peak, but remained at high levels (80% of the peak) in women at high altitude (P < 0.05). The second increase of serum estradiol occurred earlier at sea level than at high altitude. From days +12 to +15, there was a significant decline in serum estradiol levels in women at sea level (P < 0.05) but not in those from high altitude (P > 0.05). Serum progesterone levels at days +5, and +8 to +12 were significantly higher at sea level than at high altitude. CONCLUSION: Our data suggest that hormone profile during menstrual cycle is different at high altitude than at sea level, probably as an effect of low barometric pressure.

Hematocrit levels in children at sea level and at high altitude: effect of adrenal androgens.

Hematocrit values are normally higher in natives living at high altitude than in natives living at sea level. Here, we have determined the hematocrit levels in relation to adrenal androgens in children living at altitudes of 150 m and 3400 m above sea level. The data demonstrate no association between serum adrenal androgens levels and hematocrit values. For all ages studied, hematocrit levels were higher in children at high altitude than in children at low altitude. Higher hematocrit values (> or = 54%) were observed in 15% of native boys at 3400 m. These data suggest that the higher hematocrit levels observed normally in children at high altitude are mainly related to altitude hypoxia and not to adrenal androgens.

Relationship between body mass index, age, and serum adrenal androgen levels in Peruvian children living at high altitude and at sea level.

We have determined the relationship between body mass index (BMI) and serum adrenal androgen levels when age is controlled for in children, aged 7-12 years, living in Lima (150 m above sea level) and in Cusco (3400 m above sea level). The purpose of the study was to determine whether the relationship of serum adrenal androgen levels with both BMI and age differs between low and high altitude. The ratio weight/height2 is not an adequate marker of BMI because it correlates with height in children from Lima and Cusco. The ratio weight/height2.3 correlates with body weight but not with height and was used in the present study as the BMI. From age 7 to 12 years, the BMI increased significantly with age only in boys from sea level and in girls from high altitude. The study demonstrates that serum adrenal androgen levels are not related to BMI in either sea-level or high-altitude children when the effect of age is removed statistically. These data suggest that BMI in children is not related to serum levels of adrenal androgens and that delayed age of adrenarche observed in children at high altitude may be due to factors other than nutritional status.

Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men.

This study was a 12-week double blind placebo-controlled, randomized, parallel trial in which active treatment with different doses of Maca Gelatinizada was compared with placebo. The study aimed to demonstrate if effect of Maca on subjective report of sexual desire was because of effect on mood or serum testosterone levels. Men aged 21-56 years received Maca in one of two doses: 1,500 mg or 3,000 mg or placebo. Self-perception on sexual desire, score for Hamilton test for depression, and Hamilton test for anxiety were measured at 4, 8 and 12 weeks of treatment. An improvement in sexual desire was observed with Maca since 8 weeks of treatment. Serum testosterone and oestradiol levels were not different in men treated with Maca and in those treated with placebo (P:NS). Logistic regression analysis showed that Maca has an independent effect on sexual desire at 8 and 12 weeks of treatment, and this effect is not because of changes in either Hamilton scores for depression or anxiety or serum testosterone and oestradiol levels. In conclusion, treatment with Maca improved sexual desire.

Fisiología y patología de la reproducción en las grandes alturas / Physiology and pathology of reproduction at high altitude

En varones, la exposición aguda a la altura ocasiona un incremento en los niveles séricos de prolactina (PRL) y testosterona con disminución de las gonadotropinas. La espermatogénesis se altera, pero puede ser revertida con antiserotoninérgicos. En la mujer se observa anovulación cuando la exposición a la altura ocurre en la fase folicular temprana, y estaría asociada a una disminución de las gonadotropinas hipofisiarias. En la exposición intermitente a la altura se observa un estadio intermedio entre lo observado en el nativo de nivel del mar y en el de altura. En el nativo de altura los niveles séricosa de LH y testosterona son similares que a nivel del mar, mientras que la FSH se encuentra aumentada y la prolactina disminuida. El espermatograma y la respuesta de testosterona a la hCG son similares en ambas poblaciones. En mujeres de la altura se encuentra menores niveles de PRL. Los niveles de LH, estradiol y pregnandiol fueron similares a los del nivel del mar, La tasa de infertilidad en la población expuesta intermitentemente a la altura es de 10 por ciento similar a la descdrita para poblaciones a nivel del mar. La prevalencia de hiperprolactinemia en ambos sexos está significativamente reducida en la altura. En los nativos de altura con mal de montaña crónico (MMC) se encuentra disminuido los niveles de testosterona sérica, y similares los de LH y FSH a los observados en nativos normales de altura. La respuesta a la hCG se encuentra disminuida en tanto que el número de mortalidad de los espermatozoides fueron normales. La fructosa seminal, un efector de los andrógenos, se encontró disminuída en el MMC. En ancianos, la incidencia de impotencia, de ausencia de erección matinal y de hipoplasia testicular fueron similares tanto a nivel del mar como en la altura.