Endocrine Abstracts

Ageing is associated with a decline in immunity, also termed immunesenescence. This is paralleled by a decline in the production of several hormones as typically illustrated by the menopausal loss of ovarian oestrogen production. This lecture will give a brief overview of the physiology and pathophysiology of steroid hormones that decline with ageing. Therein a specific focus will be laid on the ageing-associated decline in adrenal dehydroepiandrosterone (DHEA) production, an event commonly termed as “adrenopause”. However, this term is rather imprecise as the other major outputs of adrenal corticosteroid production, cortisol and aldosterone secretion, do not change with ageing. The regulatory processes involved in the initiation and progression of “adrenopause” still remain elusive. Current research efforts importantly aim at clarifying whether “adrenopause” contributes to immunesenescence, also addressing the issue of an altered glucocorticoid/DHEA balance that necessarily occurs if cortisol remains unchanged while DHEA steadily declines. Previous research has shown that an increased cortisol/DHEA ratio increases the likelihood of early postoperative infections requiring hospitalisation in elderly patients with hip fracture and that these changes are associated with an impairment of neutrophil function. The lecture will summarise most recent results on differential effects of DHEA and cortisol on components of the immune response, including neutrophil and natural killer cell function, including first conclusive data on underlying mechanisms. Further understanding of immune-endocrine links in the pathophysiology of immunesenescence will hopefully help to develop clinical tools for improving health in our rapidly ageing population.