Navigation Links
Cell death following blood 'reflow' injury tracked to natural toxin

Researchers at Johns Hopkins have discovered what they believe is the "smoking gun" responsible for most tissue and organ damage after a period of blood oxygen loss followed by a sudden restoration of blood oxygen flow.

Working with mice, the Hopkins team found that the sudden oxygen bath triggered by restored blood flow causes cells to make a chemical so toxic it kills the cells. The work was published in two papers in the Proceedings of the National Academy of Sciences last week.

Although not sure why it happens, the Hopkins scientists believe the toxic chemical, PAR-polymer, acts like a molecular sledgehammer, or a death switch. "We've found evidence of it in cells following all types of injury," says Ted Dawson, M.D., Ph.D., the Leonard and Madlyn Abramson Professor of Neurodegenerative Diseases, professor of neurology and co-director of Hopkins' Neuroregeneration and Repair Program in the Institute of Cell Engineering (ICE).

The research team has named the cell death process caused by PAR-polymer "parthanatos," after Thanatos, the personification of death from Greek mythology.

To establish that PAR-polymer is indeed the culprit in the kind of reperfusion injuries long linked to heart attacks, strokes and a variety of blood vessel injuries, the researchers pumped mouse nerve cells full of PAR-polymer. The cells died, but to be sure PAR-polymer (and not something else) killed them, they examined the brains of mice engineered to lack an enzyme that chews up and gets rid of PAR. These mouse brains contained twice as much PAR-polymer as those of normal mice.

After the researchers induced a blood clot injury like a stroke, the same mice showed a 62 percent increase in the area of brain damage compared to normal littermates. Mice that contain more of the PAR-chewing enzyme suffered less brain damage than their normal littermates.

To figure out what triggers the death switch, the researchers tracked PAR-polymer's journey after cells made it. After 15 minutes, PAR-polymer hadn't gone anywhere. But after 30 to 60 minutes, the researchers discovered that much of it traveled right to areas where the switch normally resides.

The fate of the cell is irreversible once PAR-polymer sets off the trigger, says Valina Dawson, Ph.D., professor of neurology, co-director of the Neuroregeneration and Repair Program and author of the papers. "If we could figure out how to block PAR-polymer, we could design drugs that protect the switch and prevent cells from dying after heart attacks, stroke or other injuries," she says.


'"/>

Source:Johns Hopkins Medical Institutions


Related biology news :

1. Combination therapy boosts effectiveness of telomere-directed cancer cell death
2. Enzyme allows B cells to resist death, leading to leukemia
3. Critical role in programmed cell death identified
4. A comprehensive response to HIV could prevent 10 million AIDS deaths in Africa by 2020
5. The death of a very special chimpanzee
6. The very unexpected life and death of a leukemic cell
7. Solutions that reduce death of marine life reeled in by International Smart Gear Competition
8. Emergence of cancer as major cause of childhood death in developing countries is not being adequately addressed
9. Hanging baskets of sex and death help fruit growers
10. UT Southwestern researchers discover master switch in cell death
11. Prescription pain patch abuse blamed for increase in deaths
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:1/20/2016)...   MedNet Solutions , an innovative SaaS-based eClinical ... research, is pleased to announce the attainment of record-setting ... result of the company,s laser focus on (and growing ... it,s comprehensive, easy-to-use and highly affordable cloud-based technology platform. ... MedNet growth achievements in 2015 include: , ...
(Date:1/15/2016)... Rico , Jan. 15, 2016 Recent ... and small to find new ways to ensure data ... iOS and Android that ... on biometrics, transforming it into a hardware authorization token. ... users swipe their fingerprint on their KodeKey enabled device ...
(Date:1/11/2016)... Synaptics Incorporated (NASDAQ: SYNA ), the ... its ClearPad ® TouchView ™ 4300 touch ... categories in the 8 th Annual Mobile Excellence ... The Synaptics ® TDDI solution enables faster time-to-market, ... devices, brighter displays and borderless designs. ...
Breaking Biology News(10 mins):
(Date:2/4/2016)... , Feb. 4, 2016  Spherix Incorporated (Nasdaq: ... fostering and monetization of intellectual property, today provided an ... in the Northern District of Texas ... Inter Partes Re-examination ("IPR") proceedings ... Office.  The IPR was initiated on only certain claims ...
(Date:2/3/2016)...   ViaCyte, Inc ., a leading, privately-held ... cell-derived islet replacement therapy for the treatment of ... that ViaCyte and Janssen Biotech, Inc., one of ... have agreed to consolidate the assets of the ... ViaCyte with an exclusive license to all BetaLogics ...
(Date:2/3/2016)... BRUNSWICK, N.J. , Feb. 3, 2016 /PRNewswire-USNewswire/ ... grants totaling more than $1 million for researchers ... are working on health-related research that demonstrates exciting ... this round of funding for the New Jersey ... for faculty members at these educational institutions— Princeton ...
(Date:2/3/2016)... -- Silk Therapeutics, Inc., today announced the closing of a $6 ... a total of $10.25 million in Series A funding based ... round was led by existing investor The Kraft Group of ... investors Lear Corporation and Highland Consumer Partners, as well as ... Richard Sackler , MD, with Summer Road, LLC; Erin ...
Breaking Biology Technology: