ABSTRACT
Ineffective stress-coping in Africans is associated with cardiac ischemia during acute mental stress. Ischemic conditions may be worsened by stress-induced release of glial-derived S100calcium-binding-protein ß (S100B), which is pro-apoptotic for cardiomyocytes. Whether estradiol as coping regulator and cardio-protective factor will protect against pro-apoptotic effects, remains unclear. Therefore, we aimed to investigate stress-induced associations between cardiac troponin T/cTnT (cardiac ischemic marker), S100B and estradiol in a bi-ethnic cohort of defensive copers of both sexes. The target population study included African and Caucasian teachers of both sexes (n = 344; aged 20-65 years). The Stroop-color-word-conflict-test was administrated for 1 min to induce acute mental stress in the participants. A chronic stress risk phenotype score was obtained. The Coping Strategy Indicator determined habitual defensive/avoidance/seeking social support coping scores. Fasting blood samples were obtained prior to and 10 min post-Stroop-stress to assess cTnT, S100B and estradiol levels. An interaction between ethnicity, sex and defensive coping (p < 0.05) was found for acute stress-induced percentage changes in estradiol. In defensive coping African men, the Stroop-color-word-conflict-test elicited decreases in S100B and increases in estradiol. Again, in this group, S100B decreases were related to unchanged cTnT, a chronic stress risk phenotype and acute estradiol increases (p < 0.05). No associations among main markers were apparent in the African women or the Caucasian defensive copers of both sexes. In the defensive coping African men, the markers studied may play a relevant role in the brain-cardiovascular system interaction during stress exposure. Further research is needed to elaborate on potential mechanisms and to establish clinical relevance.
