Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cells’ Ability to Live Without Oxygen Give Clues for Treating Major Diseases

08.09.2003


Some cells in the kidney can not only survive without sufficient oxygen, but actually begin stretching and multiplying to make up for their fallen brethren, says a Medical College of Georgia researcher.




Some cancer cells similarly adapt; as a tumor grows too big for its blood and oxygen supply, some cells transform so they can survive without oxygen, emerging stronger and treatment resistant, says Dr. Zheng Dong, cell biologist.

He doubts that these two very different cell types travel the identical road to survival. “But the final result is the same,” he says. “They simply become stronger, tougher and more resistant to injury, and for those in tumors, more resistant to cancer therapies.”


The researcher, whose latest findings are featured in recent issues of the Journal of Biological Chemistry and American Journal of Pathology, is tracing the steps each takes, ultimately to see whether cells that would be lost to stroke and heart attack can be made equally durable -- and, possibly, whether cancer cells can be made vulnerable.

“We want to define the signaling pathways for cell injury and death. We want to know how these cells are killed,” he says. “Our other focus is cellular adaptation to stress, basically why other cells can survive. We want to define the molecular alterations at the level of gene expression,” which he believes are key to survival and proliferation.

He has found at least two key pieces to survival in the tubular cells of the kidney. Tubular cells are the most common cells in the kidney, comprising the extensive channels through which body’s entire fluid volume flows many times each day so that needed substances can be absorbed and excess fluid and waste excreted in the urine. The cells are durable, busy and, likely because of their high activity, have a high oxygen demand.

Yet when the oxygen supply is lost or diminished, as it can be in cardiovascular disease and diabetes, Dr. Dong has found that some tubular cells seem to adapt by up-regulating two genes, IAP-2 and Bcl-xL. When he knocks down the genes, the cell’s sensitivity to injury returns.

“This response, I believe, provides a mechanism for those cells to survive ischemic stress and gives them a chance to repair the injured kidney,” says Dr. Dong, whose discovery of the role of these death-inhibitory genes has won him numerous awards in the past three years including the Lyndon Baines Johnson Research Award from the American Heart Association, Texas Affiliate; the Patricia W. Robinson Young Investigator Award from the National Kidney Foundation; and the Carl W. Gottschalk Scholar Award from the American Society of Nephrology.

His latest finding helps explain why other cells are lost, detailing how in an oxygen-deprived state, a little-understood protein called Bax found in the fluid portion of a cell moves into the cell’s powerhouse, or mitochondria, where it forms holes in the walls. Contained, the contents of the mitochondria give the cell energy; uncontained, they cause cell death, or apoptosis.

“We are focusing on the kidney, but our studies are applicable to heart attack and stroke and possibly cancer as well,” says Dr. Dong, who believes his work will ultimately lead to gene therapy where the survival genes could be up-regulated in troubled cells and down-regulated in cells, such as cancer cells, that need to die.

“Why are some cells so durable and others so vulnerable?” he says. “Hopefully we can identify some therapeutic tool that is either genetic or pharmaceutical to switch these as needed. We want to keep kidney cells strong enough to be resistant to ischemia and hopefully we can identify a few more things in cancer cells that make them more vulnerable.”

Dr. Dong’s work is supported by the National Institutes of Health, the American Society of Nephrology and the National Kidney Foundation.

Toni Baker | Medical College of Georgia
Further information:
http://www.mcg.edu/news/2003NewsRel/dong.html

More articles from Health and Medicine:

nachricht New malaria analysis method reveals disease severity in minutes
14.08.2017 | University of British Columbia

nachricht New type of blood cells work as indicators of autoimmunity
14.08.2017 | Instituto de Medicina Molecular

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>