Researchers Restart Rat Heart

This story is a bit creepy, actually

There are other companies pursuing similar ideas...Tengion , for instance, is making good progress...

WASHINGTON (AP) — Researchers seeking new treatments for heart disease managed to grow a rat heart in the lab and start it beating.

"While it still sounds like science fiction, we've hopefully opened a new door in the notion that we can build these tissues and one day provide options for patients with end-stage disease," said Dr. Doris Taylor, director of the Center for Cardiovascular Repair at the University of Minnesota.

"We're not there yet, but at least now we have another tool in our tool belt."

Taylor led the team whose research appeared in Sunday's online edition of the journal Nature Medicine.

Scientists have worked for years for ways to grow body parts. Many efforts have focused on heart valves as an alternative to the plastic or animal valves that wear out after being implanted in humans.

An estimated 5 million people live with heart failure and about 550,000 new cases are diagnosed each year in the United States. Approximately 50,000 die annually waiting for a heart donor.

Taylor said in a telephone interview that her team began by trying to determine if it were possible to transplant rat heart cells. They took the hearts from eight newborn rats and removed all the cells. Left behind was a gelatin-like matrix shaped like a heart and containing conduits where the blood vessels had been. Scientists then injected cells back into this scaffold — muscle cells and endothelial cells, which line blood vessels.

The muscle cells covered the matrix walls and lined up together, while the endothelial cells found their way inside to coat the blood vessels, she said. Then the hearts were stimulated electrically.

"By two days we saw tiny, microscopic contractions, and by seven to eight days there were contractions large enough to see with the naked eye," she said. The tiny hearts could pump liquid at about one-fourth the rate of a normal fetal rat's heart.

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Stanford researchers get precise picture of cell target for drugs

It's too bad they didn't include the picture in the press release...

STANFORD, Calif. — More than half of all drugs given to patients work by targeting a particular type of “docking station,” or receptor, found on body cells, to steer the cell’s machinery toward healing an illness. Researchers from Stanford University School of Medicine and the Scripps Research Institute have determined what one of those receptors looks like at the molecular level, giving them the keys to greater control of the process.

A scientific feat, identifying the structure of these docking stations—called G protein-coupled receptors—can direct the future design of drugs that will precisely bind to specific receptors. Precise binding by a drug can stimulate or block that particular receptor’s normal activity, leading to more powerful treatment while minimizing bothersome side effects.

“The majority of hormones and neurotransmitters work through one of these receptors,” said Brian Kobilka, MD, the senior author of three new publications devoted to the structure of a particular G protein-coupled receptor called beta 2-adrenergic receptor. “All these receptors are structurally related, which means that knowing more about a specific one will advance the whole field.”

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Growing Nerve Cells in 3-D Dramatically Affects Gene Expression

PROVIDENCE, R.I. [Brown University] — When it comes to growing cells in a lab, technique matters. A new Brown University study shows that nerve cells grown in three-dimensional cultures use 1,766 genes differently compared to nerve cells grown in standard two-dimensional petri dishes.

The study, published in the May issue of Tissue Engineering, adds to a growing body of research showing that culture techniques can significantly affect cell growth and function. This research shows that cells grown in a laboratory in 3-D environments, not in flat petri dishes, are more like cells grown in the ultimate 3-D environment – the human body.

“More and more, we’re seeing evidence that cells cultured in three dimensions look and behave more like cells in your body,” said Diane Hoffman-Kim, the Brown bioengineer who spearheaded the new study, “so culture method is critical. If you want to better understand how the human body behaves or how new drugs might fight disease, 3-D may be a better bet.”

For more than 100 years, scientists have grown human cells in flat dishes. In these 2-D glass incubators, better known as petri dishes, cells stick to the bottom and spread out as they multiply. But in the body, cells don’t grow that way. They are suspended in fluids and gels and surrounded by other cells. And these cells aren’t stuck; they move.

As a result, some scientists suspect that hothouse cells do not behave like in vivo varieties. This means that the critical functions scientists are trying to understand by studying these cells – from the proliferation of cancer to the bacterial assault by antibiotics – may play out differently. Studies indeed show differences in behavior between cells cultured in 2-D and in 3-D. Cells cultured in 3-D, for example, grow faster.

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