CARDIOVASCULAR JOURNAL OF AFRICA • Vol 22, No 3, May/June 2011
AFRICA
151
BMI-matched Europids, and yet are more insulin resistant.
77-79
The use of high-throughput gene-screening technology, which
has yielded important information on the polygenic nature of
obesity via genome-wide association studies
132
should therefore
be used in African populations to determine the genetic input
to adiposity and body fat distribution. It is possible that ethnic
differences in insulin sensitivity and the prevalence of obesity-
related disorders are due to differences in the secretory output
of adipocytes. The comparison of adipocyte secretomes across
population groups using the new technologies developed for
the analysis of complex mixtures of bioactive molecules
133
may
therefore be very worthwhile.
The future of the use of adipose-derived stromal cells
(ADSCs) for the treatment of human disease looks very promis-
ing. Such cells have already been used to correct cranial defects
in humans,
119
and preliminary studies in man to rectify cardio-
vascular
134,135
and soft tissue
136-138
defects hold hope for the future
use of ADSCs in the treatment of muscle and cartilage defects
and heart infarcts. However, before this becomes a reality, there
are a number of technical problems that need to be overcome.
The methods used for the large-scale isolation of ADSCs and
their efficient conversion into the correct cell phenotype must be
improved and standardised. Also, the long-term safety of the use
of these cells in humans must be explored, initially by the devel-
opment of the appropriate animal models. Stem-cell therapy is
already available for the treatment of haematological malignan-
cies in specialised medical centres within Africa
139
and therefore
it is feasible that the therapeutic use of ADSCs may also become
a reality for this continent.
Conclusion
Our view of adipose tissue has changed over time. Additional
information has led us to confirm that fat is not only a store of
energy, but when in excess, it is the instigator of obesity-related
co-morbidities. The characterisation of adipokines has led to the
realisation that adipose tissue is a true endocrine organ, and the
isolation and use of ADSCs has led to hope for future therapeu-
tic treatments of degenerative diseases of fat, bone, muscle and
cartilage. Once fat was just fat, but it is now much more than
that.
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