"Magic Bullets vs. Promiscuous Plants"
During the last decade, the drug industry has followed an assumption
that a single drug hitting a single target
was the 'rational' way to design drugs,
but we're learning that Mother Nature
may be a bit more complicated than that.
Strategies for targeting single genes or proteins
ignore a very important fact that the most, if not all of diseases,
involve a sophisticated network system.
For example, one little family of immune molecules
involves like 50 different keys fitting in 20 different locks,
often acting with redundancy,
thus making selection of an appropriate specific drug
to antagonize one key or one lock may not work in the long run.
A whole list of agents has been developed to target a specific molecule
for the treatment of inflammatory bowel disease, for example,
but they have all failed.
That's why drug companies are now working on so-called
promiscuous drug that try to simultaneous affect multiple pathways.
Meanwhile, since ancient times, natural agents derived from plants—
fruits, vegetables, spices, beans, and grains—
have been preferred as potential therapeutics for most chronic diseases,
not only because of their safety, affordability, and long-term use,
but for their ability to target multiple cell signaling pathways.
This promiscuous targeting of a disease cell's
multiple bypass mechanisms is a therapeutic virtue.
One example of a successful promiscuous plant-based drug is aspirin.
It doesn't just target inflammation and offer pain relief,
but can act as a blood thinner, and help prevent pre-eclampsia
and even some types of cancer.
Curcumin is another hopeful.
Aspirin is an extract of the willow tree bark.
Curcumin is an extract of turmeric root.
It's considered so anti-inflammatory that it may even work through the skin--
a traditional use was to wrap sprains and injury
with turmeric soaked poultices,
a use that actually continues to this day.
It is so anti-inflammatory, it can help counter the effects of mustard gas.
Here is the response of spleen cells to an inflammatory cytokine,
extinguished in the presence of curcumin.
What about outside of the petri dish, though?
Promising effects have been observed in patients
with a variety of inflammatory diseases.
And one of the reasons there may be such a wide safety margin
of safety with turmeric despite its powerful pharmacological effects,
is that the same pathway promiscuity that may account for its effectiveness
may also act synergistically to neutralize side-effects.
For example, turmeric has been traditionally used
as a bronchodilator to open airways in conditions like asthma.
Many of the adrenaline-like drugs that do the same thing
can raise blood pressure,
but the reason turmeric doesn't may be because it has differerent
components with opposing activities,
so has, like, calcium channel blocking effects
that may actually lower blood pressure at the same time,
and so side effects may cancel each other out.
This strength in promiscuity, though,is also a weakness.
The U.S. Food and Drug Administration has been reluctant
to approve plant extracts,
which by definition are composed of mixtures of different compounds.
So it's like a Catch-22:
one drug, one chemical, one mechanism of action
and you can patent it, get FDA approval, and make a billion dollars,
but it may just not work very well.
On the other hand there might be a safe, natural alternative that works better,
but industry and the government may not be interested.
However, there is hope on the horizon.
Remember this video?
The FDA approved a green tea ointment as a prescription drug
for the treatment of genital warts,
making it the first prescription plant approved in the United States.
So have drug companies abandoned their model
and started pouring money into plants?
No.
Having discovered that so-called magic bullets has been largely unsuccessful,
they just propose creating non-selective drugs.
Instead of magic bullets in effect...
magic shotguns.