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Brain & Heart Cerebral ischemia biomarkers

to enable tailored interventions and improve outcomes for prognosis but also for the development of new therapeutic
patients with cerebral ischemia. interventions. By understanding the molecular pathways
involved in ischemic brain injury, potential targets for
4. Protein biomarkers in cerebral ischemia therapeutic interventions can be identified. Consequently,

Protein biomarkers are specific proteins measurable in protein biomarkers can also guide therapeutic
various body fluids or tissues that can indicate the presence interventions in cerebral ischemia. For example, brain-
or severity of a disease. Several protein biomarkers have derived neurotrophic factor, a neuroprotective protein, has
been identified for cerebral ischemia, and their levels may been shown to be a potential therapeutic target in cerebral
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provide insights into the extent of brain damage and predict ischemia. In addition, vascular endothelial growth factor,
disease outcomes. Cerebral ischemia triggers a complex which is involved in angiogenesis and neuroprotection,
series of molecular events, including neuroinflammation, has been investigated as a potential therapeutic target for
oxidative stress, and excitotoxicity. Numerous proteins cerebral ischemia. 34
contribute to these events and serve as potential biomarkers In summary, protein biomarkers play an important
for cerebral ischemia. For instance, the high mobility group role in the detection, diagnosis, and management of
box 1 protein, which is released by damaged neurons cerebral ischemia. Further research is needed to validate
and endothelial cells, has been identified as a mediator these biomarkers and explore their potential therapeutic
of inflammation and a potential diagnostic marker for implications. Although protein biomarkers are promising
cerebral ischemia. Similarly, as mentioned above, S100B, in the field of cerebral ischemia, several challenges remain,
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a calcium-binding protein released by astrocytes and including the standardization of measurement methods,
damaged neurons, has emerged as a potential biomarker for validation in different populations, and integration into
detecting ischemic brain injury and predicting prognosis. clinical practice guidelines. In addition, further research
During cerebral ischemia, astrocytes are activated and is necessary to identify new protein biomarkers and
release S100B into the bloodstream. Elevated levels of determine their role in the different stages of cerebral
S100B have been found in the CSF and blood of patients ischemia.
with cerebral ischemia, correlating with the severity of the
injury. 28,29 S100B has been shown to be a reliable biomarker 4.1. β-amyloid, tau, and phospho-tau as biomarkers
for predicting neurological outcomes and determining the in cerebral ischemia
effectiveness of treatment interventions. An important aspect of the pathophysiology of stroke is

Another promising protein biomarker for the diagnosis the disruption of protein homeostasis and the subsequent
and prognosis of cerebral ischemia is neuron-specific enolase accumulation of misfolded proteins. In recent years, several
(NSE), a glycolytic enzyme predominantly found in neurons. studies have investigated the potential diagnostic and
When cerebral ischemia occurs, NSE is released into the prognostic value of β-amyloid (Aβ), tau, and phospho-tau
bloodstream due to neuronal damage. Elevated levels of NSE biomarkers in cerebral ischemia. 36
have been detected in CSF and blood samples from patients Aβ is a known pathological hallmark of AD and is
with ischemic stroke, indicating its potential as a biomarker implicated in neurodegenerative processes. However,
for brain injury. NSE levels have been found to correlate with emerging evidence suggests that Aβ may also have a role
the extent of neurological deficit and clinical outcome. 30-32 in cerebral ischemia. A study examining the plasma of
Other protein biomarkers have also been investigated patients with acute ischemic stroke found significantly
for cerebral ischemia, including glial fibrillary acidic protein higher Aβ levels compared to healthy controls. These
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(GFAP), which is predominantly expressed in astrocytes results support the notion that Aβ may play a role in
and is elevated in CSF and blood samples from patients the acute phase of cerebral ischemia. Furthermore, Aβ
with ischemic stroke. GFAP levels have been associated deposition has been observed in post-stroke brains,
with the presence and severity of brain damage. 29,33 Another possibly contributing to long-term cognitive impairment.
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previously mentioned protein biomarker, MMP-9, is an These studies highlight the importance of Aβ as a potential
enzyme involved in the degradation of the extracellular biomarker and therapeutic target in cerebral ischemia.
matrix. Elevated levels of MMP-9 have been found in the The tau protein has been extensively studied in the
CSF and blood of patients with cerebral ischemia, and this context of neurodegenerative diseases, particularly AD.
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biomarker has been associated with disruption of the BBB Tau undergoes phosphorylation, leading to the formation
and an increased risk of hemorrhagic transformation. 34 of phospho-tau, which is implicated in the formation
The identification of protein biomarkers for cerebral of neurofibrillary tangles. Studies investigating tau and
ischemia is important not only for diagnosis and phospho-tau in cerebral ischemia are limited; however,

Volume 2 Issue 3 (2024) 6 doi: 10.36922/bh.2750