HEALTH IN ERA OF DESIGNER HORMONES,
GENETIC ENGINEERING AND
NANOTECHNOLOGY
The modern day science and technology hold promise for better
health in future. Novel solutions to the present-day health problems
are becoming available through unprecedented breakthrough in
clinical endocrinology in form of designer hormones, gene
modification through genetic engineering, and advanced pharmaceutics
through nanotechnology. The last few decades have also seen
significant progress in information technology and
bio-informatics expanding database of catalogued knowledge, which
has helped in opening new vistas of biomedical research
and advancing health-related technology.
Exciting scientific and technological developments are occurring across
all fields of medicine. Along with this, there is a gradual blurring
between disease and ‘non-disease’ states and health is being
defined in a new perspective
(1). The concept of healthy ageing is one such example
(2).
In present era better nutrition through availability of wholesome foods
and restoration of health through designer hormones, gene modification
techniques and improved drugs and drug-delivery systems, hold
promise for defeating disease and achieving healthy longevity.
DYNAMICS OF CLINICAL ENDOCRINOLOGY
The
advances in molecular biology and genetics have led to
discovery of new receptors, signaling molecules and
chemical messengers and new insights in molecular basis of
hormonal action and interactions
(3). The reverse pharmacology has helped in discovery of new
hormones, like ghrelin, obestatin and kisspeptin, and various receptors
(4,5). It is now held that
hormonal milieu comprises of diversity (6).
A hormone may bind to different receptors and a receptor can
bind to a number of hormones. The serum-binding
proteins, also, are not inert reservoirs but play a dynamic
role, whereas fatty acids, bile acids, amino acids and nitric oxide
act as bioactive signaling molecules.
There exist metabolic
sensors responding to intracellular and extracellular milieu,
and finally, brain acts as the prime regulator of neuro-endocrine
circuits
(7).
There are modern era challenges too, in form of obesity and
diabetes, and progressively ageing society
(8).
The world population is getting older and fatter with resultant
escalation in cardiovascular diseases. But, optimism prevails in
scientific circles. Effective treatments are emerging and becoming
available to slow down ageing, improve body profile like obesity,
flabbiness, baldness and hypo-sexuality. As the
hormones control growth, metabolism, fat, muscle, weight, mood
and sexual function, the clinical endocrinology will be
expected to provide solutions for various health derangements. On the
less rational grounds, health messiahs will promise and look forward to
re-tune one’s glands for fulfillment in life
(9).
DESIGNER HORMONES HOLD PROMISE
The hormones and their receptors work as keys and locks in
biological systems. A hormone fails to work when the receptors are
defective. The hormones designed to fit into the defective mutant
receptors provide the prospect to restore normal function and health
(10). For example in vitamin D resistant rickets a designer vitamin D
analogue may provide the cure. Similarly, new versions of time-regulated
reproductive hormones will make the infertility treatments easier.
Estrogen helps to protect against osteoporosis, but can cause breast and
uterine malignancy (11). Selective estrogen-receptor modulators (SERMs)
have been designed for this purpose. Estrogen by its antioxidant effect
regenerates neurones, enhances their survival and may halve risk of
developing Alzheimer’s disease. Here, a designer version of estrogen,
e.g. trimethylphenol retaining the antioxidant property but no adverse
effects may prove helpful. In the future, designer non-peptide oral
mimetics will replace insulin, GH, gonadotrophins and
parathyroid hormone, making treatment selective, versatile
and convenient (12,13).
The sexual dysfunction in women is complex and common. A 1999 University
of Chicago survey revealed that 43% US women experienced some form of
sexual dysfunction including decreased libido. Another survey of 500
Americans' attitudes toward sexuality revealed that 92% women thought
that sexual enjoyment adds to quality of life at any age and 60% of them
held that waning sexual desire should not be accepted as part of ageing.
In both the sexes, sex drive has been associated with testosterone. A
designer testosterone-based hormone based on testosterone but bereft of
its virilizing effects, Estratest, PT-14, or like, can offer solution.
FRONTIERS OF GENETIC RESEARCH
The mapping of human genome and genomes of various plants and animals,
has boosted genetic research (14). The genetic engineering, GE, in
nutshell, involves adding a gene into DNA to
express a
protein to rectify a genetic defect or introduce new characteristics or
attributes(15). This is done by isolating DNA containing the desired
gene, precisely cutting it by restriction enzymes and incorporating into
a carrier, and splicing it into the recipient DNA segment. The marker,
promoter and species barrier penetration genes assist in this process.
APPLIED GENETIC
ENGINEERING
The
development of retroviral vectors in the early 1980s, led to efficient
gene transfer into mammalian cells for the purpose of gene therapy.
Many diseases are
of
genetic origins
and
can
be corrected
by
GE. In
September
1990, United States
became the first country to successfully treat a 4 year-old girl,
lacking a gene that leads to severe combined immune deficiency by using
a gene drug. Since then,
more than a dozen different types of somatic gene drugs are being used
in approved clinical trials.
The genetic therapy may correct genetic deficits present in the
reproductive cells of prospective parents or in the embryos themselves.
It can also enhance particular traits. But, this may present threat to
our evolved socio-psychological attributes. Also, a gene insertion may
lead to destabilization of genome. Finally, we know functioning of only
about 3 percent of all DNA, there may be unknown hazards associated with
these manipulations (16).
GE has made possible to bulk produce several biologically useful
peptides, like human insulin, hepatitis B vaccine, interferons, human
growth hormone and tissue-type plasminogen activator (t-PA)(17).
Apart from this, GE has
potential to improve familiar foods apart from providing nutritional and
environmental benefits (18).
GE AND FUTURE OF MANKIND
The key difference between natural selection and selective breeding is
that the latter is always based on value judgments and utilitarian
concepts. GE and Eugenics are a form of selective breeding (19). But, in
a way we, the human race, have no choice. We have to evolve as the
climate and other things change on the earth to become extinction. The
advancements in medicine have
improved human survival. Also, we inhabit, to a large extent, in a
modified environment. These factors weaken the evolution process. We
need to realize that GE can help in better chances of our survival on
this planet.
THE NANO INNOVATIONS
The nano-science involves study of material at nano-size, whereas
nanotechnology, NT, focuses on the design, characterization and
application of nano-devices (20). The nano-particles have vastly
increased surface area compared to their mass, leading to change in
physical properties and reactivity. This phenomenon opens up new vistas
for their applications as bio-materials.
APPLIED NANOTECHNOLOGY
NT has already found many applications in industry, which is
utilizing advantages of colloidal nanoparticles in form of suntan
lotion, cosmetics, protective coatings, stain resistant textiles, etc.
NT-assisted pharmaceutics and therapeutics are progressing in a big way
to change the future healthcare scenario. The drug nanoparticles can be
produced and utilized in innovative ways (21).
During 2005, the US FDA approved 130 nm albumin nanoparticles
loaded with paclitaxel for cancer therapy. With NT, researchers are
developing biomedically targeted drug formulations that eliminate many
side effects.
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