Navigation Links
New advancements in the use of adult, embryonic stem cells for tissue regeneration
Date:11/6/2008

Indianapolis, Ind. November 06, 2008 A major issue in the development of regenerative medicine is the cell sources used to rebuild damaged tissues. In a review of the issue published in Developmental Dynamics, researchers state that inducing regeneration in humans from the body's own tissues by chemical means is feasible, though many questions must be answered before the process can reach clinical status.

Regeneration is a regulative developmental process ubiquitous across all species. It functions throughout the life cycle to maintain or restore the normal form and function of cells, tissues and, in some cases organs, appendages and whole organisms. The roots, stems and leaves of plants, for example, have extensive regenerative capacity, and entire plants can grow from single cells or small cuttings.

The regenerative capability of most vertebrate animals, however, is restricted to certain tissues. In the absence of injury, many cell types such as epithelia and blood cells turn over rapidly, while others such as hepatocytes, myofibers, osteocytes, and most neurons, have low turnover rates or do not turn over at all. In organisms that grow throughout life, such as fish, the total number of cells in various tissues increases continuously, indicating that the number of new cells produced is higher than the number of cells lost.

By contrast, the loss of normal tissue mass and/or architecture to acute injury or disease in humans requires a more intense and qualitatively different regenerative response that restores the tissue to its original state. This response is called injury-induced regeneration.

A major issue for cell transplant therapies is the source of the cells to be used. Three sources of cells can be tapped for transplant: differentiated tissues, adult stem cells (ASCs) and derivatives of embryonic stem cells (ESCs). Adult stem cells regenerate epithelia, brain tissue, muscle, blood and bone. They have also been found in other tissues that normally scar after injury, such as myocardium, spinal cord and retina tissues.

"Adult stem cell therapy has real potential to regenerate at least muscle and bone damaged by injury or genetic disease, and cardiac stem cells may be a way to regenerate new cardiomyocytes after myocardial infarction," says David L. Stocum, co-author of the paper.

Progress is also being made toward the use of ESCs to derive functional cells for treatment of diabetes and muscular dystrophy.

A procedure has been developed to direct the differentiation of human ESCs to pancreatic islet cells, including insulin producing cells. When implanted into mice, the cells produce human insulin in response to glucose stimulation and protect against hyperglycemia.

"ESCs show great promise as a cell source for the regeneration of new tissue, due to their high growth and self-renewal capacity, and their ability to differentiate into a myriad of precursor or differentiated cell types when directed by the appropriate set of environmental factors," says co-author Gnther K.H. Zupanc.

The recently acquired ability to reprogram adult somatic cells to ESCs in culture ("induced pluripotent stem cells") has solved bioethical concerns surrounding the destruction of somatic cell nuclear transfer embryos to make personal embryonic stem cells that will not be immunorejected. The authors state, however, that induced pluripotent stem cells raise their own biological and bioethical issues. Biological issues include the differentiation and survival time of reprogrammed somatic cells, and the need to develop methods to reprogram cells without introducing exogenous DNA. Ethical issues, including cost, the ease of reprogramming for the purpose of conducting unethical experiments, like the derivation of human offspring, have yet to be resolved.

The ability to reprogram adult somatic cells to ESCs in culture has led the authors to the concept that it may be possible to use natural or synthetic molecules to reprogram adult somatic cells in vivo to adult stem cells that will recapitulate the development of a tissue, organ or appendage, or to stimulate resident adult stem cells to do so. They argue that strong regenerators, such as fish and amphibians know how to do this naturally, and should be studied to learn what molecules are required for such stimulation or reprogramming. The counterparts of these molecules, or synthetic small molecules that mimic their action, could then be applied to regeneration-deficient mammalian tissues.


'/>"/>

Contact: Sean Wagner
swagner@wiley.com
781-388-8550
Wiley-Blackwell
Source:Eurekalert

Related medicine news :

1. 2008 American Academy of Pediatric Dentistry Annual Session Highlights Emerging Scientific Advancements
2. Eric J. Topol, M.D., to Present Late-Breaking Lecture About Advancements in Genomics of Cardiovascular Disease at ACCs 57th Annual Scientific Session
3. Anpath Group, Inc. Announces Advancements with Animal Care Line
4. Researchers Create Embryonic-Like Stem Cells From Human Testes
5. STEMCELL Technologies Introduces AggreWell™400 for Standardized Embryonic Stem Cell and Induced Pluripotent Stem Cell Research
6. Public funding impacts progress of human embryonic stem cell research
7. Embryonic pathway delivers stem cell traits
8. Embryonic Pathways Induce Stem Cell Traits
9. How embryonic stem cells develop into tissue-specific cells demonstrated
10. March of Dimes awards $250,000 prize to leaders in understanding embryonic development
11. Mouse Skin Cells Reprogrammed to Act Like Embryonic Stem Cells
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/13/2016)... Tennessee (PRWEB) , ... February 13, 2016 , ... ... the Infusion Nurses Society (INS) states that vein visualization technology should be used ... by healthcare facilities around the world, the INS Standards mandate the use of ...
(Date:2/13/2016)... ... ... In the early or “honeymoon” stage of a relationship, couples strive to put ... to be romantic, and may exaggerate a strength or two in an effort to ... , A recent study from Queendom.com , however, suggests that new couples who ...
(Date:2/12/2016)... San Antonio, TX (PRWEB) , ... February 12, 2016 , ... ... of love, as expressed in Blue SKies Buddha, the biography of Rama - Dr. ... in fact a love story, the love of a Buddhist teacher for teaching and ...
(Date:2/12/2016)... FL (PRWEB) , ... February 12, 2016 , ... ... non-profit organization devoted exclusively to funding innovative lymphoma research and serving the lymphoma ... – hosted over 250 members of South Florida’s philanthropic community at its 10th ...
(Date:2/12/2016)... ... February 12, 2016 , ... Each year, the American Physical Therapy ... Anaheim, CA at the Anaheim Convention Center. Almost 10,000 physical therapists across the country ... in action, learn more about their chosen field and network with their colleagues. ...
Breaking Medicine News(10 mins):
(Date:2/12/2016)... , Maharashtra, February 12, 2016 ... Market research report titled Chronic Inflammation Global Clinical ... a snapshot of the global clinical trials landscape ... clinical trials by Region, Country (G7 & E7), ... point status and reviews top companies involved and ...
(Date:2/11/2016)... 2016 Laboratory glassware and plasticware ... These may range from microscope slides to large storage ... from borosilicate glass because of its low weight and ... hand, started gaining popularity over the past decade when ... glass with plastic in several applications due to its ...
(Date:2/11/2016)... 2016 Potrero Medical, Inc., the developer of the ... appointment of George M. Rapier, III , MD, to ... , WellMed is one of the nation,s largest physician ... members in Texas and ... his own internal medicine practice, he has been instrumental to ...
Breaking Medicine Technology: