Covid related question to IR/cytokine storms

[MattCo]

I'm not sure where to post this so here it is.

I'm curious as to why diabetes is an underlying condition mentioned with covid-19. So I poked some words into google and now I need someone to explain what I found.

Here's a paper that seems to have a lot of words that I just don't understand. (Insulin Receptor-Mediated Stimulation Boosts T Cell Immunity during Inflammation and Infection; https://www.sciencedirect.com/science/a ... 3118305047). What is Insulin Receptor Signalling? I assume this has something to do with insulin but does it have anything to do with insulin resistance? The first hilight is "Insulin receptor signaling controls T cell proliferation and cytokine production." That's a curiosity because isn't over stimulation of cytokines the main reason people die from Covid-19? The cytokine storm?

I also found a paper about how obese mice had a more severe cytokine reaction to an infection than lean mice (Obesity Exacerbates the Cytokine Storm Elicited by Francisella tularensis Infection of Females and Is Associated with Increased Mortality; https://www.hindawi.com/journals/bmri/2018/3412732/). Something I could not quite understand (okay, mostly not at all) was "We conclude that increased basal leptin expression in obese individuals causes a persistent low-level inflammatory response making them more susceptible to F. tularensis infection and heightening the generation of the immunopathological cytokine storm." Is this saying obese mice are already activated to look for a fight, so to say, so when there is an infection it just lets the dam loose?

Or, if I'm just reading the wrong papers and you have a better, simple explanation of why diabetes is an underlying condition then please let me know.

Thanks, and take care.

[NF52]

I'm not sure where to post this so here it is.

I'm curious as to why diabetes is an underlying condition mentioned with covid-19. So I poked some words into google and now I need someone to explain what I found. ...
Or, if I'm just reading the wrong papers and you have a better, simple explanation of why diabetes is an underlying condition then please let me know.

Hi Matt,

I admire your scientific curiosity and wish I understood more of those terms myself! I think the short answer from scientists and doctors would be: "It's complicated, and we don't have all the answer yet." Here's a link to the American Diabetes Association which has helpful information on how to stay healthy: https://www.diabetes.org/covid-19-faq

From poking around a little, it seems like a few factors are probably important:
* People with diabetes need to manage it really well right now, to optimize their immune system and reduce the risk of infections that sometimes happen with unstable diabetes.
* People with diabetes seem to have altered immune reactions, which can lead to more severe disease. They also are more likely to have respiratory and heart disease (true for my dad, who had Type 2 diabetes and died of cardiac arrest at age 67) which has been shown to increase risk of severe COVID-19.
* People with diabetes may also be obese, which also puts a strain on the body's ability to fight novel infections.

I hope this helps; let's all stay hopeful and healthy!

[SusanJ]

Or, if I'm just reading the wrong papers and you have a better, simple explanation of why diabetes is an underlying condition then please let me know.

This is new paper, and a very technical paper, but this section seems to describe why diabetes is a risk factor.

Attack of oxidized hemoglobin by viral proteins will lead to less and less hemoglobin that can
carry oxygen. The invasion of viral proteins on deoxidized hemoglobin will cause less and less
hemoglobin that can carry carbon dioxide and blood sugar. People with diabetes can have unstable
blood sugar. The patient is aggravated by carbon dioxide poisoning. The lung cells have extremely
intense inflammation due to the inability to exchange carbon dioxide and oxygen frequently, which
eventually results in ground-glass-like lung images.

https://chemrxiv.org/articles/COVID-19_ ... n/11938173

So, higher glycated hemoglobin leads to more viral binding and less oxygen transport. Bottom line is keeping HbA1c low will be critical to keep this process in check.

[MattCo]

Thanks! Fascinating stuff. And crucial.