Scientists determine how sex hormones produce changes in the neuronal morphology

Sex hormones perform multiple regulatory functions in the brain such as proliferation, survival and cell differentiation. Estrogen and progesterone particularly control neuronal plasticity promoting recovery and brain restructure.

In a study published in Neuroendocrionology, CONICET researchers determined new paths by which sex hormones promote the formation of dentritic spines, fundamental structures for memory, cognition and learning. Besides, the research work describes how the loss or modifications at hormonal levels can be linked to the development of neurodegenerative diseases such as Alzheimer’s, Parkinson’s or dementia.

“Sex hormones produce changes in the neuronal morphology and promote the formation of dentritic spines through the control of key proteins that make the actinic cytoskeleton,” Ángel Matías Sánchez explains. He is a CONICET associate researcher and is in charge of the Laboratorio de Transducción de Señales y Movimiento Celular of the Instituto de Medicina y Biología Experimental de Cuyo (IMBECU, CONICET-UNCuyo).

For the scientist, both hormones (estrogen and progesterone) from their specific receptors use diverse regulatory proteins of the actinic cytoskeleton to make changes in the neuronal morphology promoting its capacity to form new dentritic spines boosting plasticity and the transmission between neurons.
“Although we knew that the estrogens as well as the progesterone influence the neuronal embryo development and continue acting on mature neurons, our studies helped to understand how both hormones promote changes in the plasticity, neuronal interconnection and transmission, what promises relevant biological and medical implications,” Marina Flamini, associate researcher at the same institute, describes.

The scientists managed to prove that the loss of function or activation of key regulatory proteins of the actinic cytoskeleton (CORTACTIN, WAVE1 and ARP2/3 Complex) determine a remarkable inhibition in the neuronal dentritic formation that could be related to memory or learning deficit: “This suggests that some degenerative disorders linked to the reduction or loss of estrogens and progestogens could be the result, to some extent, of lack of activation and control of proteins WAVE1 and CORTACTIN from these hormones,” Ivonne Uzair, CONICET doctoral fellow at the IMBECU, affirms.

“These events that control the neuronal plasticity are vital for the delicate working of the central nervous system; thus determining the level of knowledge, memory and learning. Future studies will lead to a better understanding of sex steroids on the dynamic control of brain physiology, what could contribute to the development of new drugs for endocrine therapies against important neurological diseases,” Sánchez concludes.