What is the connection between herpes and neurodegenerative diseases?

A study conducted by researchers at the University of Illinois Chicago shows a potential link between neurodegenerative diseases, such as Alzheimer’s disease, amyotrophic lateral sclerosis, glaucoma and herpes simplex, writes doc.ro.

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Herpes simplex affects many people throughout their lives

Herpes is a common viral infection that occurs in the form of localized blisters and affects most people on one or more occasions throughout life. Herpes simplex is caused by HSV type 1, mainly associated with oral and facial infections, or HSV type 2, mainly associated with genital and rectal infections.

Primary seizures of HSV type 1 infections occur mainly in infants and young children. HSV is transmitted through direct or indirect contact with a person with active herpes simplex, who is infectious for 7-12 days. After the initial infection, whether it is symptomatic or not, clinical manifestations may not occur throughout life, but when viral immunity is insufficient, recurrent infections are common.

Herpesviruses naturally infect the central nervous system and can lead to degenerative disorders of the brain and eyes, as well as encephalitis. However, in most people, the virus is suppressed during a primary infection before it can significantly affect the central nervous system.

Researchers at the University of Illinois Chicago have tried to find out why HSV-1 can be fatal to immunocompromised people, but not to healthy people.

Certain genes and the herpes virus contribute to neurodegeneration

A study published in Nature Communications suggests why HSV-1 is suppressed: OPTN, a retained autophagy receptor, selectively targets HSV-1 proteins for autophagy degradation. OPTN stops the growth of the virus and stops it through autophagy – “swallowing” the virus particles inside tiny vesicles called autophagosomes.

Autophagy is very selective and has significance for other viruses, scientists say. The study’s authors believe that the results of this research will apply to all eight different human herpesviruses.

For the present study, mice with distant OPTN genes were infected with ocular HSV-1. The growth of the virus was much greater in the brains of animals without OPTN, destroying local neurons and eventually leading to the death of animals. This shows that there is a faster degeneration of neurons when the OPTN is not there.

Investigators have planned further studies to look at naturally occurring mutations in OPTN, such as those reported in patients with glaucoma and ALS, and how they may affect neuronal health and HSV-1 infection.

Where there is an OPTN with mutations plus herpes, there is a recipe for creating a disaster in terms of neurodegeneration, say researchers. The study also shows that there is an impairment of the immune response in the event of a deficiency in OPTN. OPTN is needed to signal an influx of appropriate immune cells to the site of infection. When they do not exist, problems such as neurodegenerative disorders occur.

The same mechanism may apply to other viruses

Scientists believe that the results of other studies will show that other viruses, such as Epstein-Barr, Kaposi’s sarcoma or chickenpox, will share this mechanism because they share homologous proteins. Because the herpes virus stays in the neurons forever, there is speculation that it is linked to neurodegenerative diseases.

The immune system needs inflammation to constantly fight the virus, and neurons have some degree of damage due to this continuous immune response. The study also showed that animals without OPTN and infected with HSV-1 after 30 days lost their ability to recognize objects. This could be an indication that having HSV-1 along with an OPTN mutation could accelerate neuronal damage, which could result in cognitive impairment.

Scientists conclude that part of their translational research may be on how to correct problems with OPTN so that there are no problems with neurodegeneration.

How can the immune system be strengthened?

The first line of defense against viruses and disease in general is to choose a healthy lifestyle. Adherence to general health rules is the best step you can take to keep your immune system naturally functioning properly.

Every part of the body, including the immune system, works better when it is protected from environmental attacks and is supported by healthy living strategies such as avoiding smoking, a nutritious diet, plenty of vegetables and fruits, regular exercise and maintaining a healthy lifestyle. healthy weights, avoiding excessive alcohol, managing stress and avoiding infections, by frequent hand washing and thorough cooking of meat.

As we age, our immune response becomes weaker, which in turn contributes to more infections and various types of cancer. As life expectancy in developed countries has increased, so has the incidence of age-related conditions.

The immune system responds harder to attacks as we age

While some people age healthily, the conclusion of many studies is that older people are at higher risk of contracting infectious diseases and, more importantly, are more likely to lose their lives because of them.

Respiratory infections, including influenza, COVID-19 or pneumonia, are a leading cause of death in people over the age of 65 worldwide. No one knows for sure why this is happening, but some scientists note that this increased risk is correlated with a decrease in T cells, possibly due to the atrophy of the thymus with age and the production of fewer T cells to fight infections.

There seems to be a link between nutrition and immunity in the elderly. A form of malnutrition that is surprisingly common even in rich countries is known as “micronutrient malnutrition” – affected people are deficient in some essential vitamins and oligominerals. For this reason, the elderly, who tend to lack variety in their daily diet, can benefit from dietary supplements with vitamins and minerals to help them maintain a stronger immune system.