Several studies are coming out saying that blood LDH (lactate dehydrogenase) levels early in #COVID19 disease correlates with severe disease progression. This is a clue that #pyroptosis may be a the core of this disease (1/n).
https://www.medrxiv.org/content/10.1101/2020.03.24.20040162v1">https://www.medrxiv.org/content/1...
https://www.jci.org/articles/view/137244">https://www.jci.org/articles/...
https://www.medrxiv.org/content/10.1101/2020.03.24.20040162v1">https://www.medrxiv.org/content/1...
https://www.jci.org/articles/view/137244">https://www.jci.org/articles/...
What is LDH? It is an enzyme found within the cytosol of nearly all cells. Ed Miao& #39;s group showed that LDH release is a reliable way to monitor #pyroptosis, a form of cell death that depends on inflammasomes leading to plasma membrane rupture. (2/n)
https://www.ncbi.nlm.nih.gov/pubmed/23852598 ">https://www.ncbi.nlm.nih.gov/pubmed/23...
https://www.ncbi.nlm.nih.gov/pubmed/23852598 ">https://www.ncbi.nlm.nih.gov/pubmed/23...
LDH is not released by apoptosis or even hyperactivation of macrophages. It requires pyroptosis and membrane rupture shown by @jkagan1 & #39;s group. (3/n)
https://www.sciencedirect.com/science/article/pii/S1074761317305149">https://www.sciencedirect.com/science/a...
https://www.sciencedirect.com/science/article/pii/S1074761317305149">https://www.sciencedirect.com/science/a...
How might #SARSCoV2 induce pyroptosis? A study showed that #SARSCoV1& #39;s Orf8 triggers NLRP3 inflammasome activation and pyroptosis in macrophages. Whether #SARSCoV2 Orf8 also activate pyroptosis is unknown. (4/n)
https://www.ncbi.nlm.nih.gov/pubmed/31231549 ">https://www.ncbi.nlm.nih.gov/pubmed/31...
https://www.ncbi.nlm.nih.gov/pubmed/31231549 ">https://www.ncbi.nlm.nih.gov/pubmed/31...
While LDH correlates well with disease severity, this may not be the reason for severe disease. However, pyroptotic (pyro=fire, ptosis=falling) death is very immunogenic, releasing intracellular contents and can lead to blood clotting. (5/n)
https://www.ncbi.nlm.nih.gov/pubmed/31076358 ">https://www.ncbi.nlm.nih.gov/pubmed/31...
https://www.ncbi.nlm.nih.gov/pubmed/31076358 ">https://www.ncbi.nlm.nih.gov/pubmed/31...
Blood clotting is also associated with poor prognosis in #COVID19. (6/n)
https://www.ncbi.nlm.nih.gov/pubmed/32073213 ">https://www.ncbi.nlm.nih.gov/pubmed/32...
https://www.ncbi.nlm.nih.gov/pubmed/32073213 ">https://www.ncbi.nlm.nih.gov/pubmed/32...
There are other reasons why inflammasome inhibitors might be a promising approach - to increase host disease tolerance. Please see a nice thread by @padminipillai explaining this concept. (7/n) https://twitter.com/padminipillai/status/1243165595740385285">https://twitter.com/padminipi...
I believe inflammasome inhibitors should be tested for #COVID19 treatment. I& #39;ve said this before but I believe it is worth repeating here. I hope pharma companies working on developing such inhibitors for other disease indications can help
https://abs.twimg.com/emoji/v2/... draggable="false" alt="🙏🏽" title="Folded hands (medium skin tone)" aria-label="Emoji: Folded hands (medium skin tone)"> (end) https://www.nature.com/articles/d41573-019-00086-9">https://www.nature.com/articles/...