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Advanced Neurology A novel approach to mitigate muscle atrophy in GBS

A degradation of myelin and axonal proteins . It is believed
[47]
that the clinical recovery phase of GBS coincides with
remyelination (for AIDP) and axonal regrowth process (for
axonal variants) extending over a 4- to 6-month period ,
[3]
with the most significant changes occurring within the
first 10 weeks of disease onset [11,48] . However, for those
suffering from more severe GBS symptoms, recovery could
take several years . Furthermore, if the axonal damage is
[3]
widespread and includes the entire length of a nerve, the
[1]
demyelination may likely be irreversible .
B
2.3. Current management and prognosis of GBS
Since this is only a brief summary of GBS-related
management strategies, please refer to recent reviews [1,7] for
further details. As mentioned previously, the acute treatment
of GBS consists of immunotherapy, usually either PLEX or
IVIg. Before their use, mortality and long-term disability
rates were 13% and 20%, respectively . Since their
[49]
introduction, both forms of immunotherapy have shown
Figure 1. (A) Conceptual illustration of mechanisms of muscular some effectiveness in hastening recovery and improvement
disuse atrophy. 1 Pro-catabolic state within individual muscle fibers in long-term outcomes . Unfortunately, even with
[50]
– in the form of decreased muscle protein synthesis and increased immunotherapy, there still remains a significant proportion
proteolysis. 2 Inflammatory markers leading to the upregulation of of GBS patients that require intensive care, experience
MuRF-1 (muscle RING finger) and MAFbx (muscle atrophy F-box)
which promote ubiquitin-proteasome-mediated protein breakdown incomplete recovery, and develop long-term impairment
as well as caspase-3 activation, promoting cell apoptosis. 3 Buildup of related to weakness in the upper and lower limbs . The
[51]
reactive oxygen species, and subsequent increased oxidative stress levels, predictive factors for severe GBS included older age, recent
shown to induce a pro-catabolic state through the inhibition of protein history of surgery, cranial nerve impairment, and elevated
synthesis and direct sensitization of myofibrils to proteolytic breakdown. [52]
(B) Conceptual illustration of mechanisms in which omega-3 fatty acids levels of liver enzymes . GBS morality remains around
exert pro-anabolic effects on skeletal muscle tissue. A Enhanced amino 4% overall, and with 14% continuing to experience severe
acid transport in the cell, promoting increased protein anabolism. disability at 1 year . Only about 60% of patients make a
[9]
B Phosphorylation of protein kinases such as mTORC-1 and MAPK full strength recovery by the 1-year mark, with those who
leading to pro-anabolic effects. C Improved mitochondrial efficiency. have not recovered continuing only slow recovery up to
D Generalized anti-inflammatory properties. E Decreased release of pro- [9]
inflammatory cytokines through disruption of lipid mediatory synthesis. six years following initial presentation , after which no
further significant improvement is expected. In addition
conjugates , and mRNA templates for proteasomal to immunotherapies, supportive care is required to avoid
[45]
subunits , suggesting upregulation of the ubiquitin- and manage complications associated with GBS, including
[46]
proteasome system. Notably, the two major upregulated weakness, immobility, respiratory insufficiency, autonomic
genes induced by neurogenic atrophy included MuRF-1 dysfunction, and pain . Respiratory monitoring and
[51]
and MAFbx, the same genes implicated in the disuse airway protection are essential, with many individuals
atrophy pathway . eventually requiring mechanical ventilation transiently.
[35]
Other measures include deep vein thrombosis prophylaxis,
2.2. Demyelination and remyelination in GBS cardiac and hemodynamic monitoring, pain management,
The hallmark pathological presentation of GBS is management of bladder and bowel dysfunction, and
[3]
a multifocal demyelination of the PNS caused by psychosocial support . At present, there are no specific
macrophagic stripping of the myelin sheaths, leading dietary recommendations for people recovering from GBS.
to nerve conduction block and resultant weakness and Rehabilitation is another important component of
sensory impairment . This process begins with the supportive care. A systematic review linked exercise to
[47]
binding of autoantibodies to the outer surface of Schwann improved physical outcomes in the GBS population;
cells followed by the activation of complement, creating however, the evidence was quite heterogenous and the
membrane pores . Surrounding extracellular calcium systematic review contains very few high-quality studies .
[47]
[53]
enters readily through these newly formed channels, To address acute disability burden, all patients affected by
activating calcium-sensitive enzymes which can lead to the GBS should also undergo an individualized program of

Volume 2 Issue 2 (2023) 4 https://doi.org/10.36922/an.280