Estrogens and cognitive decline

November 25, 2013

Estrogens and cognitive decline

Women in menopause often have the impression they are losing their memory and can improve this symptom with a therapy based on estrogens. Estrogen deficiency has an effect on the cognitive learning ability in the perimenopausal period, and in the long run plays a very important role in cognitive decline, possibly causing dementia.

This deficiency is related to specific receptors Erα, situated in a region of the brain called hippocampus, that are progressively lost due to lack of estrogens, with harmful effects on the cholinergic function, specifically causing reduced hippocampal plasticity. Consequently the risk of memory impairment increases, especially in conjunction with chronic stress.

The estrogen receptor alfa, also known as NR3A1, is a nuclear receptor that is activated by the estrogen stimulus and is encoded by the gene Estrogen Receptor 1. The prescription of estrogens after the loss of these receptors is not effective in stopping this process. On the contrary the prescription of estrogens in a period prior to the onset of menopause allows to preserve the ERa receptors, the hippocampal cholinergic function and the neuronal plasticity and memory. The effect of the pre-menopause estrogen therapy, that allows to maintain the number of ERa receptors, persists also when the the hormones are no longer taken.

Recent literature has been able to determine that estrogen therapy reduces the risk of dementia only if it is prescribed in a specific period of time, before the ovaries stop producing hormones, i.e. before the onset of menopause.

In the limbic area is a great quantity of receptors for sex steroids, that regulate both memory and emotional states.

Estrogens are also involved, already in the early stages of prenatal development, in the reproduction of nervous cells, synaptic connections and in cerebral differentiation that influence the fine motor skill, so in particular female verbal and motor skills, such as the quickness of perception and motor ability. During menopause some of these abilities start to deteriorate, determining a consistent decrease in the neurological function in general.

The presence of a larger quantity of estrogens in adipose tissue in overweight women supposedly protects them more from cognitive decline and dementia. It is clear that the  larger quantity of estrogens that depends on the larger quantity of adipose cells can preserve cognitive functions of women during menopause, it must however be considered that a woman who is overweight or obese faces many other risks, in some cases mortal ones. As suggested by the researcher the best solution a normal weight range and, under the guidance of a specialist, a hormone therapy.