Navigation Links
Rescuing Injured Hearts by Enhancing Regeneration

Using a two-drug approach, researchers at Children’s Hospital Boston have demonstrated that it may be possible to rescue heart function //after a heart attack and protect the heart from scarring. Working with rats, they combined an agent that overcomes a natural inhibitor of cell division with a naturally occurring growth factor that encourages blood vessel growth (angiogenesis). Together, these two agents enabled heart-muscle cells to multiply and the heart to regain its function after a simulated myocardial infarction.

Normally, after a heart attack, the damaged heart muscle cannot grow back and is instead replaced by scar tissue. Excessive scarring can impair the heart’s pumping capacity and can lead to life-threatening arrhythmias. Heart-muscle cells (cardiomyocytes) normally cannot replicate in mammals, a major obstacle to regeneration. However, in a paper last year, Felix Engel, PhD, and Mark Keating, MD, in the Department of Cardiology at Children’s Hospital Boston, showed that they could coax cardiomyocytes to multiply in a petri dish by inhibiting an enzyme known as p38 MAP kinase, which normally suppresses cardiomyocyte replication. [See:

Engel and Keating (Keating is now at the Novartis Institute for BioMedical Research) now build on this finding. They studied 120 rats, some with simulated heart attacks. After the injury, the animals were randomly assigned to receive injections with a p38 MAP kinase inhibitor alone, the angiogenesis stimulator FGF1 alone, both agents together, or saline (placebo) for four weeks. Three months later, rats that had received both FGF1 and the p38 MAP kinase inhibitor had markedly improved heart function, as measured on echocardiograms: their hearts pumped almost as well as the hearts of uninjured rats. They also had reduced thinning of the cardiac wall and the least amount of scarring.

Rats receiving only the p38 MAP kinase inhibitor had increased proliferation of cardiomyocytes, but no longer had improved heart function at three months. Those receiving only FGF1 maintained their functional improvement, but did not show as much cell proliferation as those receiving the p38 MAP kinase inhibitor. Rats receiving both agents had the greatest improvements in both cell proliferation and heart function.

The findings suggest that getting cardiomyocytes to replicate is not enough to rescue heart function, but that angiogenesis is also needed, Engel says.

“Regeneration is not just making more cardiomyocytes,” he says. “Cardiomyocytes need a blood supply and oxygen to survive. FGF1 did not have a great effect on cell proliferation, but we found it was providing a new blood supply. If you just inhibit p38 MAP kinase, you don’t get blood vessels.”

Two important steps are needed to turn these findings into a treatment, Engel says. First is to show that the treatment works when not given immediately after the heart attack, since many people sustain progressive damage to their hearts from repeated minor infarctions. In this study, rats were treated soon after injury.

Second is the need to develop a safe delivery method. Because FGF1 stimulates angiogenesis, it has the potential for serious side effects if it goes to places other than the heart, possibly promoting tumor growth, for example. And the p38 MAP kinase inhibitor has been shown to damage the liver.

“Every treatment trying to induce proliferation of cardiomyocytes also carries a risk of inducing tumor growth, and thus you have to limit the time and location of treatment,” Engel adds.

One possibility is to inject smaller doses of the agents into the damaged area of the heart in gel form, or instill them through a catheter, so that they would remain in the heart and be released slowly over time. Engel and colleagues recently reported another compound that stimulates cardiomyocyte proliferation (Chemistry and Biology, Sept. 2006), and others are under investigation.

“In the end, we’d like a treatment that could be given systemically,” Engel says.


Related medicine news :

1. Stem Cell Therapy Shows Promise for Rescuing Deteriorating Vision
2. Stem Cell Therapy Shows Promise for Rescuing Deteriorating Vision
3. Mobilizing Stem Cells at the Injured Site Using Hyperbaric Oxygen Treatments.
4. Guidelines For Treating Severely Injured Patients On The Anvil
5. Engineered Tissue Implants benefited Knee Injured patients
6. A Realistic Arm on the Anvil for Injured Soldiers
7. Vitamin E supports Female Hearts
8. Reconstituted Blood Better For Young Hearts
9. A Call To Open Up The Channel Of Goodwill To Rescue The Dying Hearts
10. Surgeons in India to Mend ‘Pakistani Hearts’ by treating 70 Childrn
11. Novel Biological Pacemaker Under Construction for Weak Hearts
Post Your Comments:

(Date:11/25/2015)... ... November 25, 2015 , ... “While riding the bus, I ... Bronx, N.Y. “I thought there had to be a convenient and comfortable way to ... The PROTECTOR enables disabled individuals to safely travel during cold or inclement weather. In ...
(Date:11/25/2015)... (PRWEB) , ... November 25, 2015 , ... ... Association (PHA) announces the nation’s Periwinkle Pioneers, individuals and groups responsible for advancing ... this disease. The Periwinkle Pioneers, nominated by the public, will receive special recognition ...
(Date:11/25/2015)... ... November 25, 2015 , ... An unlikely ... resulting in a way for homeless people to have a more dignified and ... new initiative whereby they are repurposing plastic bags into sleeping mats for the ...
(Date:11/25/2015)... ... November 25, 2015 , ... Since ... providing comprehensive solutions involving adult stem cell therapies to patients with chronic degenerative ... “Regenestem” name as a Registered Trademark (RTM). , Organizations are required to hold ...
(Date:11/24/2015)... (PRWEB) , ... November 25, 2015 , ... ... and monitoring. Their Care Plan software creates an agreement between the practice ... care plan, including financial, scheduling, monitoring, notification, and projections. Click here ...
Breaking Medicine News(10 mins):
(Date:11/24/2015)... and BERN, Switzerland , November ... ARTORG Center for Biomedical Engineering Research of the University ... Division of Endocrinology, Diabetes and Clinical Nutrition of the ... start of an exclusive collaboration to develop a novel ... for the personalised delivery of insulin for diabetic patients ...
(Date:11/24/2015)... FLINT, Mich. , Nov. 24, 2015 Diplomat ... , Senior Vice President of Clinical Services, Education and Human ... (AIS) online webinar, "Oral Oncology Drugs: Health Plan Strategies for ... co-presenting with Beckie Fenrick , a consultant with the ... The webinar will ...
(Date:11/24/2015)... 24, 2015 iRhythm Technologies, Inc. , a leading ... announced that it will participate in the 27th Annual Piper Jaffray ... New York, NY . Kevin King , Chief ... 1, 2015 at 8:50am ET. --> ... . --> . --> iRhythm is ...
Breaking Medicine Technology: