American Journal Of Biomedical Science & Pharmaceutical Innovation
25
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VOLUME
Vol.05 Issue06 2025
PAGE NO.
25-27
10.37547/ajbspi/Volume05Issue06-06
Blood-Brain Barrier: Structure, Function and
Neurological Consequences Of Disruption: Role In Brain
Protection And Maintenance Of Homeostasis.
Disturbances In Strokes, Neuroinfections ,
Neurodegeneration , Tumors
Petrova Yurita Yurievna
Assistant Professor, Department of Biomedical Sciences, EMU University, Uzbekistan
Received:
17 April 2025;
Accepted:
24 May 2025;
Published:
30 June 2025
Abstract:
The blood-brain barrier (BBB) is a complex morphofunctional system that ensures selective permeability
between the bloodstream and tissues of the central nervous system. This article discusses the anatomical and
histological structure of the BBB, its key functions in protecting the brain and maintaining neuronal homeostasis.
Particular attention is paid to the mechanisms of barrier function impairment in various pathological conditions -
strokes, neuroinfections , neurodegenerative diseases and brain tumors. The consequences of BBB dysfunction
and modern approaches to diagnostics and therapy, including pharmacological modulation and targeted drug
delivery technologies are analyzed. The presented material emphasizes the importance of maintaining the
integrity of the BBB for neuroprotection and treatment of a wide range of neurological disorders.
Keywords:
Blood-brain barrier, neurohomeostasis , permeability, stroke, neuroinfections, neurodegenerative
diseases, brain tumors, cerebral edema, tight junctions , neuroinflammation.
Introduction:
The human central nervous system (CNS)
is highly sensitive to changes in the internal and
external environment, which necessitates its reliable
protection. One of the key structures that ensures the
isolation of the brain from potentially harmful
substances circulating in the systemic bloodstream is
the blood-brain barrier (BBB). This unique structure,
formed by tight junctions of endothelial cells of brain
capillaries, pericytes, astrocytes and the basement
membrane, acts as a selective filter and active regulator
of exchange between blood and nervous tissue.
The BBB not only prevents the penetration of toxins,
pathogens and immune cells into the brain
parenchyma, but also participates in maintaining ionic
balance,
nutrient
delivery,
and
regulating
neuroinflammatory reactions. Violation of the integrity
and function of the BBB underlies the pathogenesis of
a wide range of neurological diseases, including
ischemic and hemorrhagic stroke, neuroinfections ,
multiple sclerosis, Alzheimer's disease and brain
tumors.
Modern concepts of the structure and functions of the
BBB, as well as the mechanisms of its disruption, are
important not only for diagnostics, but also for the
development of new therapeutic approaches, including
methods of targeted drug delivery to the central
nervous system. The purpose of this article is to
systematize existing data on the morphology and
functions of the BBB, analyze the neurological
consequences of its disruption, and consider promising
areas in the restoration and modulation of the barrier
function in various diseases.
Purpose of the study
To study the structure and functions of the blood-brain
barrier and analyze the consequences of its disruption
in various neurological diseases.
Materials and methods
The study used modern literature data, including
experimental and clinical studies devoted to the
American Journal of Applied Science and Technology
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American Journal of Applied Science and Technology (ISSN: 2771-2745)
morphology, functions and disorders of the blood-brain
barrier (BBB). The analysis was carried out on the basis
of publications obtained from the scientific databases
PubMed , Scopus , Web of Science over the past 10
years.
To illustrate the mechanisms of BBB disruption, the
results of morphological and biochemical studies on
animal models of stroke, neuroinfections and
neurodegenerative diseases, as well as data from
clinical observations of patients with similar
pathologies are considered.
Methods included studying the barrier structure using
electron microscopy, immunohistochemical analysis of
tight junctions ( tight junction proteins ), as well as
assessment of functional permeability using contrast
imaging techniques and inflammatory biomarkers .
RESULTS AND DISCUSSION
The analysis of literature and experimental data
confirmed the complex and multi-level structure of the
blood-brain barrier (BBB), which ensures its high
selectivity and protective function. Endothelial cells
with tight junctions ( claudin , occludin , ZO-1) form the
main physical barrier, supported by astrocytic
endothelial cells and pericytes. Violation of the
integrity of these components leads to increased
permeability of the BBB and the development of
neurological complications.
Strokes are associated with significant weakening of
tight
junctions
and
activation
of
matrix
metalloproteinases (MMP-9), which is accompanied by
vasogenic edema and increased inflammation. These
processes contribute to secondary damage to brain
tissue and worsen the prognosis. Similarly, in
neuroinfections , pathogens and inflammatory
mediators destroy the barrier, facilitating access for
immune cells, but simultaneously increasing the risk of
edema and neuronal damage.
In neurodegenerative diseases such as Alzheimer's
disease and multiple sclerosis, BBB dysfunction is
associated with impaired β
-amyloid transport,
increased neuroinflammation , and lymphocyte
infiltration into the CNS, which accelerates disease
progression.
Tumor growth, especially in glioblastomas , is
accompanied by the secretion of factors that destroy
the barrier and cause vasogenic edema, which
complicates treatment and worsens the quality of life
of patients.
Modern diagnostic methods, including contrast MRI
and inflammation biomarkers , allow for timely
detection of BBB disruptions. Therapeutic strategies
aimed at barrier stabilization, MMP inhibition, and
targeted drug delivery through temporary BBB opening
show promise for improving clinical outcomes.
Thus, maintaining the integrity of the BBB is critical for
neuroprotection and effective treatment of many CNS
diseases.
CONCLUSION
The blood-brain barrier is a key element of brain
protection, ensuring selective transport of substances
and maintaining homeostasis of the central nervous
system. Disruptions in the integrity and function of the
BBB play an important role in the pathogenesis of many
neurological
diseases,
including
strokes,
neuroinfections, neurodegenerative processes and
brain tumors. Understanding the mechanisms of
barrier disruption opens up new opportunities for
diagnostics and the development of effective
therapeutic approaches aimed at restoring and
modulating its function. Further research in this area
will contribute to improving the treatment and
prevention of neurological disorders.
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