Influence of sex hormones on brain excitability and epilepsy
31 slide(s) – 00:18:58– English –2010-09-26
Background: In the last years, a growing body of literature indicates that seizures of women with epilepsy are influenced by reproductive state. It appears that steroid hormones, in particular oestrogen and progesterone, may have an effect on brain excitability, and, consequently, on frequency of epilepsy.
Objective: We have reviewed and analyzed data from literature, including both animal and clinical studies, to clarify the relationship between hormones and epilepsy. This article analyses the mechanism by which steroid hormones act on the brain and describes the known effects of sexual hormones on epilepsy.
Results: Gonadal hormones exert a profound influence on neuronal excitability, seizures, and epilepsy: oestrogen is “proconvulsant”, having a seizure-activating effect in experimental models of epilepsy and in human cerebral cortex; on the contrary, progesterone is “anticonvulsant”, exerting a seizure-protective effect in experimental models and in human studies; on the other hand, androgens can decrease ictal activity in the human brain. Furthermore, levels of oestrogen and progesterone fluctuate throughout the menstrual cycle, and, in some women with epilepsy, these fluctuations may be related to the occurrence of seizures around the time of menses or an increase in seizures in relation to the menstrual cycle, also known as catamenial epilepsy.
Conclusions: Changes in neuronal activity induced by sexual hormones seem to have an important role in the onset and evolution of different types of epilepsy. This knowledge is important as it will open new possible perspectives for the pharmacological treatment of epilepsy.