50
The Dream of Elixir Vitae
to transmit large amounts of information to the body, new
technologies will be necessary. Herein, I will first give a brief
overview of the most promising technologies to address this
problem: gene therapy and single-gene interventions, cell
therapy and stem cells, and nanotechnology. Afterwards,
I will attempt to foresee how we can cure aging based on these
technologies and what breakthroughs will be necessary.
GENE THERAPY
Gene therapy has been hailed as a major tool to deliver infor-
mation, genes in this case, to the human body. [8] Although
genes can be injected directly [9], most gene therapy methods
involve the use of a vector for the specific purpose of inserting
DNA into cells. Viruses are the most widely used vector and
several experiments have already shown the power of this tech-
nology. In one exciting discovery, virus-induced expression
of IGF-1, a growth factor, reversed age-related changes in the
skeletal muscle of mice. Increases of almost 30% in strength
were witnessed in treated old animals when compared to con-
trols. [10] If aging may be reversed by the expression of key
genes, then gene therapy holds great promise. Neuronal death
has also been delayed by the introduction of a single gene using
the herpes virus [11] and reversal of age-associated neural atro-
phy was achieved in monkeys by gene therapy. [12]
Gene therapy is promising but limited in scope due to the
inherited bandwidth constrains of the technique. Large-scale
genetic engineering is already possible in embryos [13] and
maybe our grandchildren will be born without aging. But
present-day gene therapy does not provide a technology to
cure aging in adults. The main reason is that viruses cannot
transport much genetic information. A typical virus carries
up to a few hundred thousand base pairs, which is mean-