The role of dehydroepiandrosterone levels on physiologic acclimatization to chronic mountaineering activity

Research output: Contribution to journalArticlepeer-review

Authors

  • Wen Chih Lee
  • Shu Man Chen
  • Min Chieh Wu
  • Chien Wen Hou
  • Yi Hung Laio
  • Chin Hung Lin
  • Chia Hua Kuo

Colleges, School and Institutes

External organisations

  • Shih Hsin University
  • University of Taipei
  • Yuan-Ze University

Abstract

Previous studies have reported that glucose tolerance can be improved by short-term altitude living and activity. However, not all literature agrees that insulin sensitivity is increased at altitude. The present study investigated the effect of a 25-day mountaineering activity on glucose tolerance and its relation to serum levels of dehydroepiandrosterone-sulfate (DHEA-S) and tumor necrosis factor-α (TNF-α) in 12 male subjects. On day 3 at altitude, we found that serum DHEA-S was reduced in the subjects with initially greater DHEA-S value, whereas the subjects with initially lower DHEA-S remained unchanged. To further elucidate the role of DHEA-S in acclimatization to mountaineering activity, all subjects were then divided into lower and upper halves according to their sea-level DHEA-S concentrations: low DHEA-S (n = 6) and high DHEA-S groups (n = 6). Glucose tolerance, insulin level, and the normal physiologic responses to altitude exposure, including hematocrit, hemoglobin, erythropoietin (EPO), and cortisol were measured. We found that glucose and insulin concentrations on an oral glucose tolerance test were significantly lowered by the mountaineering activity only in the high DHEA-S group. Similarly, hematocrit and hemoglobin concentration in altitude were increased only in the high DHEA-S group. In contrast, the low DHEA-S subjects exhibited an EPO value at sea level and altitude greater than the high DHEA-S group, suggesting an EPO resistance. The findings of the study imply that DHEA-S is essential for physiologic acclimatization to mountaineering challenge.

Details

Original languageEnglish
Pages (from-to)228-236
Number of pages9
JournalHigh Altitude Medicine and Biology
Volume7
Issue number3
Publication statusPublished - 1 Sep 2006

Keywords

  • EPO, Hematocrit, Insulin resistance, Lipids, Red blood cell, TNF-α