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Journal of Neurology and Neurorehabilitation Research | Volume 3

August 23-24, 2018 | Paris, France

Neurology and Neurological Disorders

18

th

International Conference on

The role of Hypoxia in periventricular white matter degeneration

Santiago Martinez Sosa

UCL Institute of Neurology, UK

T

he deep and periventricular white matter is preferentially

affected in several neurological disorders, including cerebral

smallvesseldisease(SVD)andmultiplesclerosis(MS),suggesting

that common pathogenic mechanisms may be involved in this

injury. Here we consider the potential pathogenic role of tissue

hypoxia in lesion development, arising partly from the vascular

anatomy of the affectedwhitematter. Specifically, these regions

are supplied by a sparse vasculature fed by long, narrow end

arteries/arterioles that are vulnerable to oxygen desaturation

if perfusion is reduced (as in SVD, MS and diabetes) or if the

surrounding tissue is hypoxic (as in MS, at least). The oxygen

crisis is exacerbated by a local preponderance of veins, as

these can become highly desaturated ‘sinks’ for oxygen that

deplete it from surrounding tissues. Additional hemodynamic

deficiencies, including sluggish flow and impaired vasomotor

reactivity and vessel compliance, further exacerbate oxygen

insufficiency. The cells most vulnerable to hypoxic damage,

including oligodendrocytes, die first, resulting in demyelination.

Indeed, in preclinical models, demyelination is prevented if

adequate oxygenation is maintained by raising inspired oxygen

concentrations. In agreement with this interpretation, there is a

predilection of lesions for the anterior and occipital horns of the

lateral ventricles, namely regions located at arterial watersheds,

or border zones, known to be especially susceptible to

hypoperfusion and hypoxia. Finally, mitochondrial dysfunction

due to genetic causes, as occurs in leukodystrophies or due to

free radical damage, as occurs inMS, will compound any energy

insufficiency resulting from hypoxia. Viewing lesion formation

from the standpoint of tissue oxygenation not only reveals that

lesion distribution is partly predictable but may also informnew

therapeutic strategies.

Speaker Biography

Santiago Martinez Sosa is a medical student at University College London, from

where he also received his bachelor’s in Neuroscience (Hons). His interests include

hippocampal physiology, neuroinflammation, and neurodegenerative disease. He

is the UCL Medical Society coordinator for the Neurology society, which serves to

facilitate student involvement in all branches of the specialty. This is his first publication.

e:

zchamar@ucl.ac.uk