Cofilin as the master regulator of the key covid inflammatory trigger NLRP3 and microglia activity as well as of the Shank3 protein effects: possible therapeutic implications for the brain and the body affected by Covid-19 infection


The NLRP3 inflammasome was identified as one of the most important inflammatory and apoptosis triggers in covid patients. i Its role in the inflammatory brain pathology caused by covid19 is also established. For example, the spike protein can increase the production of NRLP3 protein in microglia. ii The importance of this fact is highlighted by the Oxford study showing the loss of gray matter in the brain of covid patients even without a severe covid disease course. iii

Given the significant NRLP3 involvement of Covid-19- and spike protein pathology, we may shed light on the possible long-term consequences of Covid-19 infection or spike protein toxicity in the future.

NRLP3 activation is associated with certain types of cancers, cardiovascular disease, obesity-induced insulin resistance, several autoimmune diseases. iv v vi It is made responsible for the increased covid related mortality of obese people. vii The spike protein primes NRLP3 to increased activation in macrophages. viii

NRLP3 activation is also associated with several diseases of the Central Nervous System (CNS), such as autism, schizophrenia, Alzheimer’s, a broad spectrum of psychiatric diseases, brain injury caused by cardiac arrest. ix x xi xii xiii

One of the central mechanisms of NLRP3 activation in brain cells may be the NLRP3 dependent downregulation of the Shank family proteins. xiv Deficits in the Shank3 protein are associated and causally related to multiple neuropsychiatric diseases, such as autism, schizophrenia, bipolar disorder, Alzheimer’s. xv Patients born with Shank3 deficits are characterized by regressions, loss of skills, disturbances of mood, early dementia, and a broad spectrum of psychiatric symptoms. xvi xvii

One of the most promising therapeutic targets of rescuing Shank3 deficiency-related neuropsychiatric problems is the inhibition of overactivated cofilin. xviii xix

A natural method of inhibiting overactivated cofilin may be the intranasal administration of proinsulin c peptide. According to a study, in lymphocytes c peptide inactivates cofilin.xx

The cofilin inactivation may be a general solution of inhibiting also the overactivated NLRP3 inflammasome because the knockdown of cofilin reduced NLRP3 activation. xxi

It may be also of importance that in a neural stem cell in vitro model, Shank3 deficiency increased the expression of NLRP3 and caspase 1. xxii In this way the spike protein may affect brain development also. Indeed, in an in vitro model spike protein induced defective dendritic spines and shortened dendritic length. xxiii The effect of spike protein on the development of neuronal cells is reminiscent of the neuronal defects caused by Shank3 deficiency. xxiv

In the long-term brain effects of Covid-19, it cannot be excluded, that a vicious circle is building characterized by a downregulated Shank3 due to NRLP3 activation and by activated NLRP3 due to Shank3 downregulation. The potential vicious circle may be stopped by the inactivation of cofilin in the brain by intranasal proinsulin c peptide.


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xxiii https://www.biorxiv.org/content/10.1101/2020.12.03.409763v1
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