11. PPAR-α, Sulfatide and Liver Disease
As we have already stated, an experiment by Mishra and Banerjea (2021)
demonstrated that the spike protein induces the release of exosomes
containing microRNAs that specifically interfere with IRF9 synthesis
[50]. In this section we will show that one of the consequences of
suppression of IRF9 would be reduced synthesis of sulfatide in the
liver, mediated by the nuclear receptor peroxisome
proliferator-activated receptor α (PPAR-α).
Sulfatides are major mammalian serum sphingoglycolipids which are
synthesized and secreted mainly from the liver [161]. They are the
only sulfonated lipids in the body. Sulfatides are formed by a two-step
process involving the conversion of ceramide to galactocerebroside and
its subsequent sulfation. Sulfatide is expressed on the surface of
platelets, erythrocytes and lymphocytes. Serum sulfatides exert both
anti-coagulative and anti-platelet-activation functions. The enzyme in
the liver that synthesizes sulfatide, cerebroside sulfotransferase, has
specifically been found to be induced by activation of PPAR-α in mice
[162]. Therefore, reduced expression of PPAR-α leads to sulfatide
deficiency.
PPAR-α ligands exhibit anti-inflammatory and anti-fibrotic effects,
whereas PPAR-α deficiency leads to hepatic steatosis, steatohepatitis,
steatofibrosis, and liver cancer [163]. In 2019, a seminal
experiment was conducted by a team of researchers in Japan on mice with
a defective gene for PPAR-α [161]. These mice, when fed a high
cholesterol diet, were susceptible to excess triglyceride accumulation
and exacerbated inflammation and oxidative stress in the liver, along
with increased levels of coagulation factors. The mice also manifested
with decreased levels of sulfatides in both the liver and the serum. The
authors hypothesized that cholesterol overload exerts its toxic effects
in part by enhancing thrombosis, following abnormal hepatic lipid
metabolism and oxidative stress. They showed that PPAR-α can attenuate
these toxic effects through transcriptional regulation of coagulation
factors and upregulation of sulfatide synthesis, in addition to its
effects in ameliorating liver disease. They proposed that therapies such
as fibrates aimed at activating PPAR-α might prevent
high-cholesterol-diet-induced cardiovascular disease.
Tracer studies have shown that the mRNA from mRNA vaccines migrates
preferentially to the liver and spleen, reaching higher concentration
there than in any other organs [130]. Thus, there is potential for
suppression of IRF9 in the liver by the vaccine. IRF9 is highly
expressed in hepatocytes, where it interacts with PPAR-α, activating
PPAR-α target genes. A study on IRF9 knockout mice showed that these
mice developed steatosis and hepatic insulin resistance when exposed to
a high-fat diet. In contrast, adenoviral-mediated hepatic IRF9
overexpression in obese mice improved insulin sensitivity and
ameliorated steatosis and inflammation [164].
Multiple case reports in the research literature describe liver damage
following mRNA vaccines [165-167]. A plausible factor leading to
these outcomes is the suppression of PPAR-α through downregulation of
IRF9, and subsequently decreased sulfatide synthesis in the liver.
12. Guillain Barré Syndrome and Other Neurological Conditions
GBS is an acute inflammatory demyelinating neuropathy associated with
long-lasting morbidity and a significant risk of mortality [168].
The disease involves an autoimmune attack on the nerves associated with
the release of pro-inflammatory cytokines.
GBS is often associated with autoantibodies to sulfatide and other
sphingolipids [169]. Activated T cells produce cytokines in response
to antigen presentation by macrophages, and these cytokines can induce
autoantibody production through epitope spreading [170]. The
antibodies, in turn, induce complement activation, which causes
demyelination and axonal damage, leading to severe injury to peripheral
neurons [171]. The spike protein has been shown to bind to heparan
sulfate, which is a sulfated amino-sugar complex resembling the sulfated
galactose in sulfatide [172]. Thus, it is conceivable that spike
also binds to sulfatide, and this might trigger an immune reaction to
the spike-sulfatide complex.
As described in the previous section, impaired sulfatide synthesis in
the liver due to suppression of IRF9 will lead to systemic sulfatide
deficiency over time. Sulfatide deficiency can have major impact in the
brain and nervous system. Twenty percent of the galactolipids found in
the myelin sheath are sulfatides. Sulfatide is a major component of the
nervous system, found in especially high concentrations in the myelin
sheath in both the peripheral and the central nervous system.
Deficiencies in sulfatide can lead to muscle weakness, tremors, and
ataxia [173], which are common symptoms of GBS. Chronic
neuroinflammation mediated by microglia and astrocytes in the brain
leads to dramatic losses of brain sulfatide, and brain deficiencies in
sulfatide are a major feature of Alzheimer’s disease [174]. Mice
with a defect in the ability to synthesize sulfatide from ceramide show
an impaired ability to maintain the health of axons as they age. Over
time, they develop redundant, uncompacted and degenerating myelin
sheaths as well as deteriorating structure at the nodes of Ranvier in
the axons, causing the loss of a functionally competent axoglial
junction [175].
Angiotensin II (Ang II), in addition to its profound effects on
cardiovascular disease, also plays a role in inflammation in the brain
leading to neurodegenerative disease [176]. The SARS-CoV-2 spike
protein contains a unique furin cleavage site not found in SARS-CoV,
which allows the extracellular enzyme furin to detach the S1 segment of
the spike protein and release it into circulation [177]. S1 has been
shown to cross the blood-brain barrier in mice [178]. S1 contains
the receptor binding domain that binds to ACE2 receptors, disabling
them. When ACE2 receptor signaling is reduced, Ang II synthesis is
increased. Neurons in the brain possess ACE2 receptors that would be
susceptible to disruption by S1 released from spike-containing exosomes
or spike-producing cells that had taken up the nanoparticles in the
vaccines. Ang II enhances TLR4-mediated signaling in microglia, inducing
microglial activation and increasing the production of reactive oxygen
species leading to tissue damage, within the paraventricular nucleus in
the brain [179].
Overexpression of Ang II is a causal factor in neurodegeneration of the
optic nerve, causing optic neuritis, which can result in severe
irreversible visual loss [180]. Multiple case reports have described
cases of optic neuropathy appearing shortly after mRNA vaccination for
COVID-19 [181,182]. Other debilitating neurological conditions are
also appearing shortly after vaccination, where a causal relationship is
suspected. A case study based in Europe tracking neurological symptoms
following COVID-19 vaccination identified 21 cases developing within a
median of 11 days post-vaccination. The cases had diverse diagnoses
including cerebral venous sinus thrombosis, nervous system demyelinating
diseases, inflammatory peripheral neuropathies, myositis, myasthenia,
limbic encephalitis, and giant cell arteritis [183]. Khayat-Khoei
et.al. (2021) describe a case series of 7 patients, ages ranging from 24
to 64, presenting with demyelinating disease within 21 days of a first
or second mRNA vaccination [184]. Four had a prior history of
(controlled) MS, while three were previously healthy.
Hearing loss and tinnitus are also known rare side effects of COVID-19.
A case study involved a series of ten COVID-19 patients who suffered
from audiovestibular symptoms such as hearing loss, vestibular
dysfunction and tinnitus [185]. The authors demonstrated that human
inner ear tissue expresses ACE2, furin and the transmembrane protease
serine 2 (TMPRSS2), which facilitates viral entry. They also showed that
SARS-CoV-2 can infect specific human inner ear cell types.
Another study evaluating the potential for the SARS-CoV-2 virus to
infect the ear specifically examined expression of the receptor ACE2 and
the enzymes furin and TM-PRSS2 various types of cells in the middle and
inner ears of mice. They found that ACE2 and furin were “diffusely
present in the eustachian tube, middle ear spaces, and cochlea,
suggesting that these tissues are susceptible to SARS-CoV-2 infection.”
[186]. Tinnitus is positively associated with hypertension, which is
induced by elevated levels of Ang II [187].
Headache is a very common adverse reaction to the COVID-19 mRNA
vaccines, particularly for people who are already susceptible to
headaches. In a study based on a questionnaire involving 171
participants, the incidence of headaches was found to be 20.5% after
the first vaccine, rising to 45.6% after the second shot [188]. A
case study described a 37-year-old woman suffering from a debilitating
migraine attack lasting for 11 days following the second Pfizer/BioNtech
mRNA vaccine [189].
Steroids are often used as adjunct therapy to treat migraine [190].
Dexamethasone and other steroids stimulate PPAR-α receptors in the liver
through the steroid receptor, thus offsetting the effects of IRF9
suppression [191]. A theory for the origins of migraine involves
altered processing of sensory input in the brainstem, primarily
trigeminal neurons [192]. The trigeminal nerve is in close proximity
to the vagus nerve in the brainstem, so spike-carrying exosomes could
easily reach it along the vagal route. Magnetic resonance imaging has
revealed that structural changes in the trigeminal nerve reflecting
aberrant microstructure and demyelination are a characteristic feature
of people who suffer from frequent migraine headaches [193]. A
potential factor linked to either SARS-CoV-2 infection or mRNA
vaccination is an excessive level of Ang II in the brainstem due to
spike inhibition of ACE2 receptors. ACE inhibitors and Ang II receptor
antagonists have become popular drugs to treat migraine headaches
off-label [194,195]. Migraine headache could thus arise from both
the spike protein’s disruption of ACE2 receptors and the destruction of
the myelin sheath covering critical facial nerves through a microglial
inflammatory response and loss of sulfatide. The source of that spike
protein could be either exogenous or endogenous.
13. Bell’s Palsy
Bell’s palsy is a common cranial neuropathy causing unilateral facial
paralysis. Even in the Phase III clinical trials, Bell’s palsy stood
out, with seven cases appearing in the treatment arm as compared to only
one in the placebo group [196,197]. A case study reported in the
literature involved a 36-year-old man who developed weakness in the left
arm one day after vaccination, progressing to numbness and tingling in
the arm and subsequent symptoms of Bell’s palsy over the next few days.
A common cause of Bell’s palsy is reactivation of herpes simplex virus
infection centered around the geniculate ganglion [198]. This, in
turn, can be caused by disruption of type I IFN signaling.