reason for blood vessel damage in diabetics

[Guest guest]

Cause of Blood Vessel Damage in People with Diabetes Discovered

Researchers have identified a key mechanism that appears to contribute to

blood vessel damage in people with diabetes....

Advertisement

<http://ads.diabetesincontrol.com/www/delivery/ck.php?oaparams=2__bannerid=2

5__zoneid=17__cb=249149dc75__oadest=http%3A%2F%2Fad.doubleclick.net%2Fjump%2

FN6625.148224.DIABETESINCONTROL%2FB5128550.3%3Babr%3D%21ie4%3Babr%3D%21ie5%3

Bsz%3D300x250%3Bord%3D%5Btimestamp%5D%3F>

Advertisement

The researchers said studies in mice show that the damage appears to involve

two enzymes, fatty acid syntheses (FAS) and nitric oxide syntheses (NOS)

that interact in the cells that line blood vessel walls. First author

Xiaochao Wei said, " We already knew that in diabetes there's a defect in the

endothelial cells that line the blood vessels. "

" People with diabetes also have depressed levels of fatty acid synthase. But

this is the first time we've been able to link those observations together. "

Wei studied mice that had been genetically engineered to make FAS in all of

their tissues except the endothelial cells that line blood vessels. These

so-called FASTie mice experienced problems in the vessels that were similar

to those seen in animals with diabetes. " It turns out that there are strong

parallels between the complete absence of FAS and the deficiencies in FAS

induced by lack of insulin and by insulin resistance, " said Clay F.

Semenkovich, the Herbert S. Gasser Professor of Medicine, professor of cell

biology and physiology and chief of the Division of Endocrinology,

Metabolism and Lipid Research, Washington University in St. Louis, Missouri.

Comparing FASTie mice to normal animals, as well as to mice with diabetes,

Wei and Semenkovich determined that mice without FAS, and with low levels of

FAS, could not make the substance that anchors nitric oxide synthase to the

endothelial cells in blood vessels. " We've known for many years that to have

an effect, NOS has to be anchored to the wall of the vessel, " Semenkovich

said.

" Xiaochao discovered that fatty acid synthase preferentially makes a lipid

that attaches to NOS, allowing it to hook to the cell membrane and to

produce normal, healthy blood vessels. " In the FASTie mice, blood vessels

were leaky, and in cases when the vessel was injured, the mice were unable

to generate new blood vessel growth.

The actual mechanism involved in binding NOS to the endothelial cells is

called palmitoylation. Without FAS, the genetically engineered mice lose NOS

palmitoylation and are unable to modify NOS so that it will interact with

the endothelial cell membrane. That results in blood vessel problems.

It's a long way, however, from a mouse to a person, so the researchers next

looked at human endothelial cells, and they found that a similar mechanism

was at work.

" Our findings strongly suggest that if we can use a drug or another enzyme

to promote fatty acid synthase activity, specifically in blood vessels, it

might be helpful to patients with diabetes, " Wei said.

Journal of Biological Chemistry. Jan. 2011

<http://www.diabetesincontrol.com/advertising/10458-warmer-houses-may-increa

se-obesity-and-diabetes>

<http://www.diabetesincontrol.com/advertising/10458-warmer-houses-may-increa

se-obesity-and-diabetes> Warmer Houses May Increase Obesity and Diabetes

<http://www.diabetesincontrol.com/>

<http://www.diabetesincontrol.com/advertising/10456-electronic-health-record

s-can-improve-diabetes-care>

<http://www.diabetesincontrol.com/advertising/10456-electronic-health-record

s-can-improve-diabetes-care> Electronic Health Records Can Improve Diabetes

Care

<http://www.addthis.com/bookmark.php?v=250 & pub=diabetesincontrol> Bookmark

and Share| Print

<http://www.diabetesincontrol.com/index.php?option=com_content & view=article &

id=10457 & catid=1 & Itemid=17 & action=1> | Category

<http://www.diabetesincontrol.com/index.php?option=com_content & view=category

& id=53> | Home <http://www.diabetesincontrol.com/index.php>

This article originally posted 01 February, 2011 and appeared in

Complications and Co-morbidities

<http://www.diabetesincontrol.com/topics/complications-and-co-morbidities> ,

Issue 559

<http://www.diabetesincontrol.com/diabetes-in-control-newsletters/559>

Past five issues: Issue

<http://www.diabetesincontrol.com/index.php?option=com_labels & view=label & lab

el=559 & Itemid=12> 559 | Issue

<http://www.diabetesincontrol.com/index.php?option=com_labels & view=label & lab

el=558 & Itemid=12> 558 | Diabetes

<http://www.diabetesincontrol.com/index.php?option=com_labels & view=label & lab

el=dcms18 & Itemid=12> Clinical Mastery Series Issue 18 | Issue

<http://www.diabetesincontrol.com/index.php?option=com_labels & view=label & lab

el=557 & Itemid=12> 557 | Diabetes

<http://www.diabetesincontrol.com/index.php?option=com_labels & view=label & lab

el=dcms17 & Itemid=12> Clinical Mastery Series Issue 17 |

Diabetes In Control Advertisers

<http://ads.diabetesincontrol.com/www/delivery/ck.php?oaparams=2__bannerid=7

__zoneid=5__cb=ee7535f284__oadest=http%3A%2F%2Fclk.atdmt.com%2FDHC%2Fgo%2F28

7603991%2Fdirect%2F01%2F>