Tag: Muscular Dystrophy

Italian Researchers Publish Research on Stem Cell Treatment for Muscle Tissue

Italian researchers recently reported the results of their research with stem cells in mice that one day might offer a way to treat victims of muscular dystrophy.

Muscular dystrophy is a broad category of a number of genetic diseases that cause the muscles to gradually deteriorate. In many cases, muscular dystrophy leads to extremely shortened life expectancies — those born with the most common form of the disease, Duchenne muscular dystrophy, only survive on average into their early 20s.

Italian researchers performed tests in mice of stem cells called mesangioblasts. Mesangioblasts were only recently discovered in fetal blood vessels.

When the researchers injected mesangioblasts into the mice, the stem cells were able to pass from blood vessels into surrounding muscle tissue. In addition, once they were in the muscle tissue, they helped regenerate damage to the muscle tissue.

This research raises the possibility that someday a genetically engineered stem cell might be able to be introduced into the blood stream of muscular dystrophy victims and not only repair existing damage, but also correct the genetic defect that causes the disease in the first place.

Lead researcher Dr. Giulio Cossu is quick to point out, however, that the prospect of such a cure is a long way off,

Although these results are exciting, we have not cured the mice. We believe this is a significant therapy, but the question that keeps me awake at night is whether this will work in larger animals. I’m convinced this is an important result, but this is still not the therapy — for the mice or for patients.

Sources:

Stem cell treatment for muscular dystrophy. The BBC, July 11, 2003.

Muscular Dystrophy might be treatable; stem-cell research yields hopeful signs. Robert Cooke, New York Newsday, July 15, 2003.

Frankie Trull's Nice Summary of Animal Research

Frankie Trull, president of the Foundation for Biomedical Research, wrote a nice op-ed about animal research that was picked up by the Orlando Sentinel. I particularly liked her summary of the important role that animal research has played in improving the lot of humankind,

Advances in genetic engineering have enabled scientists to develop excellent rodent models for research. The availability of “transgenic mice” (which have added genes) and “knock-out mice” (which have disabled genes) has revolutionized our understanding of cancer, Parkinson’s disease, cystic fibrosis, heart disease, memory loss, muscular dystrophy and spinal cord injuries. The so-called “nude mouse” — lacking a functioning immune system — has become an incredibly important model for understanding cancer suppression.

Thanks to animal research, many diseases that once killed millions of people every year are either treatable or have been eradicated altogether. Immunizations against polio, diphtheria, mumps, rubella and hepatitis save countless lives, and the survival rates from many major diseases are at an all-time high, thanks to the discovery of new drugs, medical devices and surgical procedures. According to the American Cancer Society, the fight against cancer has seen 24 significant biomedical advances in the past 30 years.

None of them could have occurred without animal research.

Eight of the discoveries required the use of living animals, and virtually all of those that did not use animals relied on information gained from earlier animal studies. Six of the discoveries were recognized with a Nobel Prize, among them: the bone-marrow transplantation technique; cloning of the first gene; and discovery of proto-oncogenes in normal DNA, showing that a normal cell could have latent cancer genes.

And, of course, animal rights activists lie and distort the realities of almost every one of those discoveries. The other day, for example, I ran across a site where the author was claiming that animal research played no role at all in the isolation of the AIDS virus.

If that’s true, I have to ask this: what exactly were the rabbits that Gallo used in December 1983 to produce the first HIV-specific reagent which allowed him to test for the presence of HIV? This test was crucial in allowing Gallo to follow Since they were not animals, were these vegetables or minerals?

Currently marketed tests for HIV typically use a variety of animal antibodies. I cannot wait for animal rights activists to produce an alternative taxonomy which explains how these animals are not really animals but something else — or else, confess that they know very little about medical research aside from what they copy and paste from the same tired “factsheets”.

Source:

Animal-test research has saved many human lives. Frankie L. Trull, The Orlando Sentinel, April 7, 2002.

Animal Research Yields New Clues About Myotonic Dystrophy

    While animal rights activists were busy fire bombing the cars of researchers in Great Britain in early September, the journal Science reported a stunning breakthrough in understanding myotonic dystrophy thanks to a savvy neurologist and genetically modified mouse.

    Myotonic dystrophy afflicts about 40,000 Americans — it is the most common form of muscular dystrophy. The disease causes progressive muscle weakness that often starts by causing stiffness in the hands and eventually makes it extremely difficult for victims to walk, swallow or breathe. Almost nothing is known about the disease. In 1992 researchers discovered the genetic defect on the chromosome that causes the disease, but so far that knowledge hasn’t gotten researchers very far.

    The obvious solution was to create an animal model for the disease, but until the new research, the numerous efforts to create mice afflicted with symptoms of myotonic dystrophy failed. Neurologist Charles Thornton managed to succeed, however, where others had failed, and his breakthrough pointed to an immediate puzzle that might help break research into the disease wide open.

    Like human beings with myotonic dystrophy, the genetically modified mice suffer from a degenerative stiffening of the muscles. Thornton’s research team added a genetic defect into mouse chromosomes that closely resembles the genetic defect in human chromosomes (in normal genes, a particular base sequence is repeated about 30 times, whereas in the genes of those who suffer from myotonic dystrophy, the base sequence is repeated literally hundreds of thousands of times).

    The results were fascinating — the muscle stiffness in the mice was caused by an accumulation of messenger RNA (mRNA) in the nuclei of the muscle cells of the mice.

    This, to my knowledge, is an unprecedented discovery. Messenger RNA is supposed to be little more than an instruction manual for building DNA. Think of RNA as a sort of robot builder — it collects the proteins it needs in the environment and then assembles them according to its instructions to create a DNA strand which it then sends off to do the job of building the body. Genetic diseases occur when the RNA has faulty instructions and thus builds faulty DNA.

    What Thornton’s team found, however, was that large numbers of mRNA were somehow accumulating in the nuclei of the muscle cells and causing damage to those cells in ways that will require a lot more research to understand. As Thornton put it,

Normally, messenger RNA transmits genetic information out of the nucleus and into the main part of the cell where its instructions are carried out. That’s its only job. In this case, it seems to stay in the nucleus, and it’s doing something entirely different that’s harmful. The messenger itself is actively making cells sick.

    This is the sort of basic science discovery that would be very difficult to arrive at relying solely on experiments with human beings — in fact decades of research on muscular dystrophy never even came close to suggesting the possibility that RNA of all things might be capable of damaging muscle tissue. As Thornton eloquently described the benefits of using mice in a press release,

Why all the fuss over mice? Well, it is possible to test dozens or even hundreds of potential treatments in mice in a short span of time. Without an animal model, it takes several years and some risks to test just one treatment in people. I’m hopeful that these mice will accelerate the discovery process.

    Thornton’s discovery opens up a whole line of previously unknown areas that have implications not only for myotonic dystrophy, but for diseases such as Huntington’s and Fragile-X syndrome which are caused by similar genetic defects.

Source:

New mouse marks latest stride in muscular dystrophy research. EureakAlert!, press release, September 6, 2000.