brainfog – BioQuakes

Many individuals experience sickness after they have already been cured of COVID. This is called long COVID, symptoms include cognitive problems also referred to as brain fog. Having these issues leads to a decreases in memory and concentration making it harder to function in everyday life. Now imagine still feeling sick even though you really are not sick with the virus, not a good feeling. These symptoms are now believed to come from blood clots triggered by the virus. The blood clots leave behind proteins in the blood so researchers are able to find and diagnosis patients who think they have symptoms after they have had COVID.

A study by Nature Medicine found that blood tests could point signs of long COVID. 15 % of people who contracted the virus develop long COVID symptoms. Symptoms of long COVID could last for months and possibly even years. This condition is difficult to treat and diagnose due to the wide range of symptoms it causes. These symptoms include brain fog, chest pain, dizziness, and joint pains. We all know what it is like having these pains so are able to understand how difficult it is to go through your everyday life with long COVID. Scientists are still trying to figure out if the virus stick around in the body or if it leads to other reaction, like having an autoimmune response.

The lead researcher Maxime Taquet, along with others from the University of Oxford, conducted an experiment in the United Kingdom. They tracked over 1,800 hospitalized COVID patients between the years 2020 and 2021. After six and twelve months the scientists conducted cognitive assessments and took blood samples. These are tests you still want to do good on. The blood tests revealed that the patients dealing with brain fog had specific proteins in their blood, proteins that we all have in common. The first protein is called D-dimer, which is present when blood clots breakdown. The patients with this protein did not do poorly on their cognitive tests so their memory and concentration is in tact. On the other hand these patients experience shortness of breath. This could be a sign the blood clots are taking place in the lungs causing the brain to not get enough oxygen levels. The second protein found in some patients is called fibrinogen. This protein is synthesized in the liver and stops bleeding. The patients who had this protein complained about memory impairment and sadly they also did not do well on the cognitive test.

D-dimer Formation

Another test was conducted, analyzing around 50,000 people in the United States looking for D-dimer and fibrinogen. Higher D-dimer levels were only found in people who previously had COVID, while high levels of fibrinogen correlated with brain fog whether or not a person previously had COVID. This indicates that fibrinogen is involved in other cognitive conditions.

Human Fibrinogen

Although scientists know there is a relationship between blood clots and long COVID, there still needs to be more research done. Even the blood in your body could help research! Research is currently being done on how the SARS-CoV 2 spike protein affects the fibrinogen protein, and research treatments for clot dissolving medications. This is challenging though since the symptoms and diagnosis of long COVID is still difficult to spot. Scientist will continue studying blood samples and patients suffering from long COVID to better understand the sickness.

The research being conducted can be related to the AP Bio class about the role of the immune system is response to the virus. The immune system is very responsive when COVID is introduced to the body and when it is gone in long COVID patients. A study was conducted and it was found that participants with long COVID had higher levels of non-conventional monocytes and activated B lymphocytes. They had lower levels of type 1 conventional dendritic cells and central memory T cells. The B cells are responsible for attacking pathogens that are free floating, and T cells are responsible for attacking pathogens in infected cells. The dendritic cells break down pathogens and present the antigen on its surface for it to then be found by the T helper cells to pass on the information. These participants’ antibody responses is also stronger against the SARS-CoV-2 spike protein. Those who do not have long COVID do not have responses as strong. Long COVID participants also are more susceptible to other diseases. Other disease, once in the body can trigger the body to have more and worse symptoms. All these specific parts of are immune system all work together in all of our bodies to form the way we each combat infections. We should all be grateful for processes our bodies go through to help us get through our everyday lives.

The Long Term Effects of COVID-19 Hidden Behind the Fog

By shaliva

On December 7, 2023

In Student Post

COVID-19 was one of the biggest pandemics in United States history. It changed everything including schooling and many other aspects of life, but do you ever seem to forget what life was like before COVID-19? You may be thinking am I just getting old? Why am I losing my memory? Well, findings in Nature Medicine have shown that you may be suffering from what they are calling “Brain Fog”. This Brain Fog can result in recurring memory and concentration lapses that can make it difficult to function every day. You may be thinking, how does this even relate to COVID? Well, It is believed that this brain fog is developed from blood clots triggered by COVID.

Before we get into the brain fog, I want to explain how the body first reacts to COVID-19 entering your cells. AP Bio we learned, that your body activates its innate and adaptive immune systems. First, the innate system releases mast cells which release histamine along with macrophages that secrete cytokines. Cytokines are small proteins that are crucial in controlling the growth and activity of other immune system cells and blood cells. When released, they signal the immune system to do its job. We then see natural killer cells take out any damaged or infected cells while cytokines attract smaller phagocytes called neutrophils and digest pathogens. Along with the Innate response we see the Adaptive response. The adaptive response relies on B lymphocytes and T lymphocytes. The B lymphocytes create the humoral response while the T activates the cell-mediated response. Both are just as important but different. When T-helper cells recognize the antigen it triggers both responses. In the cell-mediated response, the T-memory cells prevent reinfection while the T-killer cells go and kill any infected cells. In the Humoral response the B-plasma cells, secrete antibodies that bind to and neutralize the pathogen which is then engulfed by a macrophage, while B-memory cells also prevent reinfection. Even with all this protection people may still be left with long last symptoms including brain fog.

To find out if this brain fog really came from COVID, a psychiatrist from Oxford named Maxime Taquet took samples of over 1,800 people in the U.K. who had been hospitalized due to COVID-19 and made 6 six-month checks on their symptoms. When examining the blood, they found that people who still had “brain fog” tended to have elevated levels of at least one of two proteins. The first protein is called a D-dimer protein which is produced when a blood clot breaks down. Patients with high amounts of D-dimer tend to have memory problems yet the cognitive side seems to still be intact. Doctors believe these effects were caused by blood clots in the lungs, which lead to low oxygen levels in the brain. The second and seemingly more dangerous protein to find mass amounts of is fibrinogen. This protein is produced in the liver and causes clotting to stop bleeding. When patients have elevated amounts of fibrinogen during COVID-19, they seem to have memory loss along with scoring poorly on the cognitive test. These patients show signs of dementia. Taquet believes that fibrinogen may have caused blood clots in the brain or somewhere else that directly affects the brain.

After hearing about the findings Resia Pretorius was very excited. From her own research, she has found connections between COVID and brain fog. She believes that the spike protein of COVID binds to the fibrinogen and causes it to change shape. But she believes this discovery can help determine ways to cure long COVID symptoms. So have you been affected by COVID’s brain fog or are you just getting old?

Is Brain Fog Becoming Clear?

By deukaryota

On January 5, 2023

In Student Post

Has anyone ever tried to talk to you the second after you woke up? It’s almost impossible to comprehend what they’re saying within those first ten seconds that you’re awake, right? Now imagine if those ten seconds lasted weeks, months, or even years, and you’ll be imagining the life of someone with post-COVID-19 brain fog.

“Brain fog,” is a feeling of confusion, inability to concentrate, fatigue, and overall “cloudy” mindedness that is a common residual symptom of the SARS-CoV-2 virus, affecting about forty percent of people who experience “long COVID” symptoms. Although unable to be detected through any sort of medical examination or test, post-COVID brain fog can have an overwhelming presence, causing people to be unable to work and frequently lasting for over a year. However, because brain fog only became an extremely common complaint of patients since the COVID-19 pandemic started, scientists know very little about the symptom.

In an attempt to discover more, scientists at Karolinska Institute, led by Carl Sellgren, researched how the SARS-CoV-2 virus affects the brain by infecting organoid brain cells with SARS-CoV-2. The experiment revealed that the virus caused neuron synapses to be destroyed at an unnaturally high rate. As we learned in AP Biology, neurons are signaling cells that exist throughout the body but make up most of the brain. Neurons are not actually connected- a small gap, called a synapse, between the end of one neuron (or the presynaptic membrane) and the start of the next (called the postsynaptic membrane) separates the two cells. Neurons signal each other by sending small particles called neurotransmitters across the synapse and into the next cell. Another common brain cell is microglia, which are immune system cells that dispose of dead cells and repair synapses. Microglia also destroy synapses, or connections between neurons, when they are no longer needed.

Sellgren’s study revealed that SARS-CoV-2 causes microglia in the brain to amplify the rate at which they destroy synapses, preventing many neurons from being able to make connections with other neurons. Assuming that a full human brain would respond the same way as brain organoids, this discovery explains why long-COVID patients with brain fog experience difficulty thinking. Amplified microglia activity is also associated with aging, which further supports the results of Sellgren’s experiment because people oftentimes become more forgetful with age.

With this new discovery to open the gates to more knowledge, scientists can begin to understand post-COVID brain fog more deeply and potentially hope for treatment for this symptom that affects the lives of thousands of people.

BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: brainfog

Blood Clotting Proteins Predicting Signs of Long COVID

The Long Term Effects of COVID-19 Hidden Behind the Fog

Is Brain Fog Becoming Clear?

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