Researchers have discovered that Covid-19 infection can, in the long term, damage GnRH neurons and affect several cognitive abilities such as memory, attention and concentration.
- GnRH neurons control certain processes related to reproduction, such as puberty, the acquisition of secondary sexual characteristics and fertility in adulthood.
- Covid-19 infection impairs the function of GnRH neurons, according to a new study.
- Patients whose GnRH neurons have been impacted by Covid-19 may present more problems with memory, attention and concentration.
Shortness of breath, cough, fatigue, loss of taste or smell, malaise after exercise, fever, depression, cognitive dysfunction, etc. In a study, published in the journal eBioMedicineresearchers have just discovered a new symptom of long Covid: the disease damages certain neurons and affects several cognitive abilities such as memory, attention and concentration.
An alteration of neurons in patients affected by Covid-19
According to’Health Insurance, a person is said to have long Covid – prolonged symptoms following a Covid-19 infection – when they have symptoms for more than four weeks. These sometimes last a long time: more than twelve weeks and sometimes even several months. In France, more than two million people had a post-Covid condition, that is to say long Covid, in 2022, according to Public Health France.
In this new study, the team of researchers focused on GnRH (Gonadotropin-Releasing Hormone, a hormone) neurons which control certain processes linked to reproduction, such as puberty, the acquisition of secondary sexual characteristics and fertility. adulthood.
To measure the impact of Covid-19 infection on these GnRH neurons, they analyzed the hormonal dosages of 47 men taken at two different times: three months and one year after infection. Thus, they observed an alteration in the functions of GnRH neurons and a drop in testosterone in certain patients.
Problems with memory, attention and concentration
Another observation by the researchers: these patients – with abnormal hormonal dosages and a drop in testosterone levels – reported more problems with memory, attention, and difficulty concentrating than the others.
“Although these are measurements carried out on a small sample of patients and only males, these results are very interesting and deserve to be further explored in other studies carried out on a larger scale.”, explains Waljit Dhillo, professor at Imperial College London, co-last author of this study, in a communicated.
Finally, scientists also studied the cortex of patients who died from Covid-19. They thus discovered that the virus was present in the hypothalamus – where the GnRH neurons are located – and that part of the GnRH neurons had died.
“These results can be worrying on several points with regard to the role of these neurons in reproduction and their involvement in certain cognitive functions, concludes Vincent Prévot, research director at Inserm, co-last author of this study. They point to the need to optimize and generalize medical monitoring of people with persistent symptoms following infection with Covid-19.”
