Posts tagged pluripotent stem cells
Articles and news from the latest research reports.
Researchers use stem cells to show connection between neural cell disruption and Parkinson’s disease
A diverse team of biologists has shown using induced pluripotent stem cells (iPSCs) that a gene mutation that causes malformations in the structure of the nuclear envelope of neural cells, is associated with Parkinson’s disease. In their paper published in the journal Nature, they describe how they found iPSC cells taken from Parkinson’s patients over time demonstrated the same cell disruption found in neural cells taken from other deceased patient’s with the disease. They also found that by introducing a compound known to disrupt the gene mutation, that they could reverse the cell malformation.
Parkinson’s disease is a degenerative disorder of the nervous system characterized by shaking, slowness of movement and difficulty walking. Over time most patients succumb to dementia and eventually die. Much research has centered on the disruption and death of dopamine-generating cells as the root cause of the disorder despite evidence that such a disruption would not result in all of the symptoms Parkinson’s patient’s exhibit. For that reason, researchers have looked to other causes.
In this new effort, the researchers looked at possible reasons for disruption to the nuclear envelope, the thin film that separates the nucleus from the cytoplasm in neural cells. Such disruptions have been associated with Parkinson’s but no definitive correlation has been found, until now.
To gain a better understanding of what might be causing such disruptions, the research team obtained samples of induced iPSCs from Parkinson’s patients and allowed them to grow in an external environment. They noted that the same disruptions occurred as the iPSCs grew into neural cells, suggesting a genetic cause. Prior research had indicated that a mutation of the LRRK2 gene was connected to Parkinson’s disease but no clear indication of the mechanism involved had been found. Testing the cells derived from the iPSCs showed the same mutation, implicating it as a possible cause of the disorder. The researchers also induced the mutation in human embryo stem cells and found that they too developed the same disruption as they grew into neural cells as was found with the iPSCs.
Next the researchers generated a line of iPSCs minus the mutation and found that the cells did not develop the disruptions. They followed that up by adding a chemical compound known to disrupt the mutation to already affected cells and discovered that it prevented them from being disrupted as well.
The researchers don’t know why the mutation occurs but believe a new therapy for treating Parkinson’s patients might be on the horizon as a result of their research.
(Source: medicalxpress.com)
Nobel Winner’s Stem Cells to Be Tested in Eye Malady in 2013
Stem cells derived from a mouse’s skin won Shinya Yamanaka the Nobel Prize. Now researchers in Japan are seeking to use his pioneering technology for an even greater prize: restoring sight.
Scientists at the Riken Center for Developmental Biology in Kobe plan to use so-called induced pluripotent stem cells in a trial among patients with macular degeneration, a disease in which the retina becomes damaged, resulting in loss of vision, Yamanaka told reporters in San Francisco.
Companies including Pfizer Inc. (PFE) are already planning trials of stem cells derived from human embryos. The Japanese study will be the first to use a technology that mimics the power of embryonic cells while avoiding the ethical controversy that accompanies them.
“The work in that area looks very encouraging,” John B. Gurdon, 79, a professor at the University of Cambridge who shared the Nobel with Yamanaka, said in an interview in London.
Yamanaka and Gurdon shared the 8 million Swedish kronor ($1.2 million) award for experiments 50 years apart that showed that mature cells retain in latent form all the DNA they had as immature stem cells, and that they can be returned to that potent state, offering the potential for a new generation of therapies against hard-to-treat diseases such as macular degeneration.
Cell reprogramming: much promise, many hurdles
Research in reprogrammed cells, which on Monday earned the 2012 Nobel Prize, has been hailed as a new dawn for regenerative medicine but remains troubled by several clouds.
Britain’s John Gurdon and Japan’s Shinya Yamanaka were honoured with the world’s paramount award in medicine for induced pluripotent stem cells (iPSCs).
They discovered that a mature, adult cell can be turned back to an infant, versatile state called a stem cell.
First theorised in the late 19th century, stem cells are touted as a source of replacement tissue, fixing almost anything from malfunctioning hearts and lungs, damaged spines, Parkinson’s disease or even baldness.
The first human trials were launched only in 2010, and progress has been dogged by the contested use of stem cells taken from early-stage embryos, where the most adaptable, or pluripotent, cells are found.
Created by Yamanaka in 2006, iPSCs ease the moral row as they derive from adult cells and not embryos, said University of Oxford ethics professor Julian Savulescu. Ordinary skin cells can be used as the starting material.
"Many people objected to the creation of embryos for research, describing it as cannabalizing human beings," he said.
Making it easier to make stem cells
The process researchers use to generate induced pluripotent stem cells (iPSCs)—a special type of stem cell that can be made in the lab from any type of adult cell—is time consuming and inefficient. To speed things up, researchers at Sanford-Burnham turned to kinase inhibitors. These chemical compounds block the activity of kinases, enzymes responsible for many aspects of cellular communication, survival, and growth. As they outline in a paper published September 25 in Nature Communications, the team found several kinase inhibitors that, when added to starter cells, help generate many more iPSCs than the standard method. This new capability will likely speed up research in many fields, better enabling scientists around the world to study human disease and develop new treatments.