594.3.2.4 Degenerative Disc Disease
Intervertebral discs are fibro cartilaginous structures that stabilize the spine and
allow motion between vertebral bodies. Discs are composed of a central cellular and
gelatinous nucleus pulposus and a tougher outer collagen containing annulus fibro-
sus. Age related disc degeneration mediated by increased expression of enzymes
that degrade the extracellular matrix around the disc, eventually result in loss of disc
hydration and disc height. This wear of the disc result in association with facet joint
hypertrophy can result in spinal canal stenosis and clinically present with back pain.
Due to their ability to stimulate endogenous intervertebral disc cells and promote
formation of extracellular matrix and thus restore the structure of the degenerating
disc, stem cells have been studied in several clinical trials. One of these studies
performed in ten patients 1 year after local injection of mesenchymal stem cells into
the nucleus pulposus showed both clinical (improved back pain and disability) as
well as radiological improvement (improvement in water content of the disc as seen
on T2 weighted images) [ 29 ]. Beneficial effects using MRI have been assessed in
several other similar studies with improvement seen in parameters such as increased
T2 signal and height of the disc [ 30 ] (Fig. 4.4).
4.4 Gastrointestinal System
4.4.1 Cirrhosis
Cirrhosis of the liver is the end result of several pathologic processes such as chronic
viral hepatitis, long term alcohol use, fatty liver, drugs and several other causes.
Cirrhosis carries high morbidity and mortality with liver transplantation being the
only definitive treatment. However, owing to shortage of donor livers world wide,
Injection into nucleus
pulposusDegenerated
intervertebral discRehydrated
intervertebral discFig. 4.4 Role of stem cells in degenerative disc disease with improved hydration after treatment
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4 Clinical Applications of Stem Cell Transplant in Treating Non-Hematologic...