Cardiovascular disease is the leading cause of death globally and accounts for nearly 1 trillion dollars in costs annually.
A heart attack strikes 2.8 million Indians and 7,35,000 Americans each year and heart disease is the number one killer world wide.
Heart attacks are a form of ACS- Acute coronary syndrome.
ACS is when the arteries that carry blood, oxygen and nutrients get blocked.
A heart attack also is known as myocardial infarction
1. Dr. Reena G. Desai
Dolat Usha Institute
of Applied Sciences,
Valsad, Gujarat
2. Cardiovascular disease is the leading cause of death globally
and accounts for nearly 1 trillion dollar in costs annually.
Heart attack strikes 2.8 million Indians and 7,35,000
Americans each year and heart disease is the number one killer
world wide.
Heart attack are a form of ACS- Acute coronarysyndrome.
ACS is when the arteries that carry blood, oxygen and
nutrients get blocked.
Heart attack also known as myocardial infarction.
3.
4. During heart attack, the artery that supplies blood to the heart
is blocked & heart tissue begins to die.
Blood flow can be restored by reopening the artery, but
patients often don’t undergo this procedure until an hour or
two after their first symptoms.
So, researchers are very interested in alternate ways to get
oxygen to heart muscle when blood flow is obstructed.
5. When you have a heart attack, two things your heart
needs to start repairing its damaged tissue. Oxygen &
Sugar.
Dr. Joseph Woo of Standford university found a way to
use our tiniest photosynthezing friends to help our hearts
heal themselves.
Dr.Woo & his team successfully replaced blood with
microscopic cyanobacteria, plant like organism that also
use photosynthesis.
6. An innovative method for correcting myocardial ischemia is
by implementing a photosynthetic system where light, rather
than blood, fuels cardiomyocytes.
7. USEOF PLANT
Dr. Woo started out by trying actual plants like kale &
spinach.
They were trying to separate out the chloroplast but
once isolated they quickly become inactive.
Researchers needed were self contained photosynthetic
machines, which would function as miniature
greenhouses for the heart.
8. These tiny organism make a living by taking in carbon dioxide
& water and spitting out oxygen.
Cyanobacteria : Synechococcus elongatus
Domain : Bacteria
Phylum : Cyanobacteria
Class : Cyanophyceae
Order : Synechococcales
Family : Synechococcaceae
Genus : Synechococcus
Species : Synechococcus elongatus
9. Synechococcus elongatus is a naturally occurring unicellular
cyanobacterium.
It has traditionally been a research model for the study of
circadian rhythms and used for enhanced production of
biofuels using CO2 as a carbonsource.
Mostly found in marine environment.
Size : Greater than 2 um
Rod shaped cells contain 2-3 thylakoid membrane
It is easily engineered genetically to manipulate its metabolic
activity for enhanced production of O2 andglucose.
10. Dr. Joseph Woo & his team grew a strain of Synechococcus in
their lab and injected to the impaired heart tissue of living rat.
Cardiomyocytes were isolated from 1 to 3 day old neonatal
rats using an isolation kit.
On 24 well tissue culture plates :
1. Three wells with isolated cardiomyocytes.
2. Three wells were plated with cardiomyocytes along
with S. elongatus
3. Three wells contains S. elongatus alone.
4. Three wells contained cell growth medium alone.
11. Dulbecco’s modified Eagle medium with 10 % FBS was used
as medium.
Plates were cultured at 37 ͦ C for 16 hours.
Then, they turned up the lights. 18 inch fluorescent plant bulbs
were used as light source.
After 20 min, they saw increased metabolism in damaged area.
Overall cardiac performance improved after 45 minutes.
Oxygen & sugar Synechococcus created through
photosynthesis was enhancing tissue repair.
Researchers didn’t find any immune response after a week of
monitoring.
12. first successful utilization
a means of correcting
Study demonstrates the
photosynthetic system as
ischemia.
of a
tissue
The S. elongatus use interstitial H2O and CO2 released by the
oxygen depleted cell and convert it to glucose and O2 with
light serving as the energy source.
This treatment resulted in augmented tissue oxygenation,
increased myocardial surface temperature likely to secondary
to metabolic activity, and greatly enhanced LV function in an
ischemic setting.
13. Synechococcus elongatus coexit with cardiomyocyets under
mammalian physiological conditions in vitro & enhances
cellular metabolism during hypoxia.
14. ischemic myocardium with S. elongatusTreatment of
significantly increases tissue oxygenation during acute
myocardial infection.
15. Cellular viability was assessed using a WST-1 cell proliferation
assay. Cardiomyocytes cultured with S. elongatus demonstrated
significantly enhanced cellular metabolism in presence of light.
16. Thermal imaging was used to quantify epicardial surface
temperature as a measure of myocardial energetics.
17. S. elongatus yields durable improvements in ventricular
performance after transient ischemia.
18. Cyanobacteria therapy is nontoxic and
nonpathogenic.
After injecting living bacteria into body organ, we
might expect an infection. But interestingly, the
researchers didn’t find any immune response after a
week of monitoring.
By 24 hrs after injection, nearly all injected
cyanobacteria had been cleared, with only a small
number of cells remaining in the intersitium.
19. One potential problem with making this procedure a
viable treatment is its timing and complexity.
Treating heart attack is a race against the clock & by the
time patients are transferred to a special facility equipped
to inject Cyanobacteria to the heart, it might be too late.
It’s of course possible that the bacteria will react
differently in humans. Also, the procedure required an
open chest, a dangerous and invasive surgery that most
doctors prefer to avoid.
If such a technique were ever going to work for human
patients, it would need to be modified to male it less
invasive.
20. As the technique is developed, the bacteria may be bound
to an antibody that targets heart cells, letting researchers
inject the treatment in any vein, rather than directly into
the heart.
The team is trying to figure out a way to shine the light
the bacteria needs through the skin and ribs.
If this technique works, it could also be used to keep
donated organs healthier by supplying them with oxygen
while they are being transported to the recipient.
Dr. Woo is working on genetically modifying the bacteria
so that they can be even more efficient producing more
oxygen. And the team is moving closer to performing the
therapy on larger animals like sheep and pigs.
21. The fact that researchers will saw healthier hearts in rats
that underwent treatment after a month could be a
promising results.
Scientist are now trying the technique in human subject.
Next they'll try it in larger animal models that are closer
to humans & they’re working on ways to deliver & shine
light on cynobacteria without an open heart surgery.
Researchers also try to develop a synthetic version of
photosynthesizing machinery present in Cyanobacteria.
22. Cohen, J.E., Goldstone, A. B., Paulsen, M. J., Shudo, Y.,
Steele, A. N., Edwards, B. B., ... & Jaatinen, K. J.(2017). An
innovative biologic system for photon-powered
myocardium in the ischemic heart. Science advances, 3(6),
e1603078.
Michelle Bach, November 5 (2017). Photosynthetic bacteria
to power the heart. Stanford University.
Catherine Caruso, June 14, 2017. Bacteria harnessed to
provide oxygen to the heart during a heart attack.
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