Modulation of Leukocyte hsp70 Expression by Gender, Menstrual Cycle Phase and Oral Contraceptives

The current studies revealed that leukocyte hsp70 expression, serum leptin, cortisol and prolactin were differentially modulated by gender, menstrual cycle phase and oral contraceptive use indicating alterations in immune response and stress response pathways. This is the first report of changes in leukocyte hsp70 expression in response to gender, menstrual cycle phase and oral contraceptive use. These results have important implications for the design and interpretation of human clinical studies investigating leukocyte hsp70 expression in females or mixed gender cohorts. These results have highlighted the gender-based differences in hsp expression, however, individual differences should not be discounted when planning clinical trials. The use of each participant as their own 'control' is, therefore, strongly recommended. Whether estrogen has direct effects on leukocyte hsp70 expression remains to be determined. The results of the current small-scale, pilot study, investigating the effects of gender, menstrual cycle phase and oral contraceptive use on hsp expression did not find a direct association between serum estradiol and leukocyte hsp70 expression. Although a number of researchers have reported effects of estrogen on hsp70 expression, these effects appear to be localized to particular tissues and cell types, suggesting that estrogen may modulate hsp70 expression via differential mechanisms. Given the intricate links between the endocrine system, the HPA axis, the cardiovascular system, immune function and stress activated pathways, the results of the current studies indicated that further studies should be conducted to investigate the connections among these systems and the mechanisms by which leukocyte hsp70 expression is modulated.