Heart disease continues to rank as the number of killer of people all over the globe. Each year it is estimated that nearly 20-40 million people die from heart disease. The two common heart disorders associated with the highest mortality include congestive heart failure and an acute myocardial infarction. Over the years, many advances have been made in the treatment of heart disease but they all remain palliative. Most treatments only treatment of symptoms of heart disease and do not cure the disorder. When a patient suffers from a heart attack, the heart muscle in many cases is damaged and develops into a scar, which has no pumping ability. Once heart muscle is damaged, it cannot be reversed and despite all the presently available treatments, heart disease is progressive.

One of the major research accomplishments in the past decade has been the identification of human cardiac stem cells. In the years following this exciting discovery, researchers have been able to show that cardiac stem cells can in fact regenerate heart cells over the

course of one’s life. This observation rekindled hope of using stem cells to repair heart muscle damaged after an acute myocardial infarction. It also dispelled the long-held belief that the heart was not capable of repairing its own tissues after injury.

However, it is important to understand that no physician or scientist has been approved by the FDA to conduct stem cell studies in human hearts in the USA. All the work is experimental or done elsewhere.

Since that initial discovery of stem cells, scientists have been trying to come up with ways to help repair or replace damaged heart muscle cell. Today a lot more is known about individual heart cells, how they function and transmit electrical signals. In addition, the biochemistry and metabolism of heart cells is quite well known.

Presently researchers are able to grow embryonic heart cells in the laboratory. These cells have been obtained from heart biopsies performed during surgery. In addition, scientists have also induced-pluripotent stem cells that have been programed to behave like embryonic stem cells, which have the capacity to become any type of heart cell.

Most of the stem cells and research on the heart has been done in the laboratory and the results have been promising. Animal studies show that cardiac stem cells can be used to repair and replace some heart muscle cells, but so far the researchers are not able to determine where these cells reside once they are injected and how they become activated.

Other research has shown the human pluripotent cells may also be useful in the treatment of heart disease. They may also help predict which patients are susceptible to adverse effects of drugs or how they respond to cancer treatment. Similarly, patches of stem cells have been applied with special adhesive glue to damaged areas of the heart to determine if the tissues can be regenerated.

The majority of stem cell studies on the heart have been done in Europe where researchers have injected bone marrow cells into the coronary vessels. Bone marrow cells are known to secrete factors that can help stimulate growth and also modulate the immune system. This is important because when stem cells are transplanted from one person to another, there may not be any need for chemotherapeutic agents. Over 1,000 patients have been transplanted with various populations of bone marrow stem cells for heart disease and so far the procedure has been found to be safe and partially beneficial.

Researchers are now looking at methods of inducing genes or growth factors that can helps stimulate the heart cells to grow. Other research involves use of endothelial progenitor stem cells that line the blood vessels, in the hope of making new vessels that can deliver oxygen to the damaged heart.

Most of the clinical trials are in the very early stages and the results will not be known for a few more years. It is also important to note that already many companies have been promoting use of stem cells for treatment of a variety of heart disorders. Consumers should be aware that these are not FDA approved therapies and there is no evidence that these treatments work, since no clinical trials have been completed. These “fee for service” companies charge thousands of dollars for providing unproven stem cell cures. Until more data are available, the adage, “Buyer Beware” should be heeded well when it comes to stem cell cures.

Stem cells to regenerate the lens in infants

Stem cells have been in the news for the past few years. While they have been used sporadically to treat a number of medical disorders, there have been very few reports about actual regeneration of a body organ with these cells. With so many restrictions on stem cell use in western countries, not many institutions have used these cells to grow human organs.

Well now researchers from the Shiley Eye Institute at the University of San Diego combined with colleagues in China and have developed a new regenerative medical approach to treating congenital cataract in newborn infants. These researchers first tested the system in animals and then applied the technique to 12 newborn infants born with cataracts.

Cataracts are known to cause clouding of the lens in newborn infants and can cause blindness. The clouded lens is known to obstruct the passes of light to the retina resulting in poor visual information processing by the brain. The current treatment of cataracts in newborns is removal of the cataracts followed by corrective eyewear.

In this study the researchers used the ultimate power of the stem cells by regenerating human tissue. After the cataracts were removed in these infants, the integrity of the lens membrane was preserved to help give the lens shape. From prior research, the researcher left the lens epithelial stem cells intact along the edges.

After 3 months, a clear regenerated biconvex lens developed in all 12 infants. Six months after the surgery, all children who were treated in this fashion had a complete lens in both eyes, and the surgical openings made to the lens capsule were healed. Vision testing revealed that the children’s vision was as good as those who underwent conventional surgery.

This pioneering work shows that it is possible to regenerate human organs. The researchers are now looking to expand their research to help treat adults with cataracts. Cataracts affect millions of people all over the world and are a leading cause of blindness. In adults who undergo cataract surgery, the natural lens is removed, and an artificial intraocular lens is implanted. Unfortunately, more than 50% of adults who undergo this surgery are left with poor vision and the need for eyeglasses.

With this innovative research, there is hope that stem cells may be used to treat adults who undergo cataract surgery. However, the difficulty is that removal of cataracts in adults is quite difficult and the lens may not have any more residual stem cells to regenerate the organ.

http://ucsdnews.ucsd.edu/pressrelease/stem_cells_regenerate_human_lens_after_cataract_surgery_restoring_vision

Over the past few years, there have been almost daily reports about stem cells and their miraculous medical benefits. There are countless reports of stem cells being used to treat patients with various illnesses. But what exactly are stem cells?

Stem cells are a group of undifferentiated cells that have the potential to differentiate into almost any type of specialized cell. In general stem cells can be derived from the embryo or adult tissues.  Adult stem cells can be found in almost any tissue but unlike the embryo their numbers are limited. The adult stem cells are usually in a non-dividing state and only become activated if there is tissue injury or a need for repair.

The adult stem cells have the ability to self renew indefinitely enabling them to generate several types of cells types or even regenerate an entire organ. It was initially believed that adult stem cells had a limited ability to differentiate only into the tissues of their origin but now evidence indicates that they can also differentiate into other cell types.

Embryonic stem cells have the potential to differentiate into any cell or an organ-for example you can theoretically create a clone human. The embryonic stem cells are those that are derived from a 4-5 day old embryo.

When stem cells are isolated they are placed in a controlled environment that prevents them from specializing or differentiating but permits them to divide and replicate. This process allows for having a large number of stem cells when needed.

The potential to differentiate into other cell types further classifies stem cells. Embryonic cells are the most potent as they have the ability to differentiate into any cell type.

So how can stem cell help?
For many years, researchers have been studying stem cells for treatment of many medical disorders. Because these cells have the potential to differentiate into any cell type, their potential is unlimited. One of the major uses of stem cells has been to regenerate tissues. At the moment there is a serious shortage of organs for transplantation. Stem cells could potentially be used to grow a new organ. For example after a major burn to the skin, stem cells could be used to replace the burnt skin. In China, eye surgeons recently used stem cells to grow a new lens after removal of cataracts. Scientists are also studying stems cells for the treatment of diabetes.
Other studies involve using stem cells to replace brain tissues in people with Alzheimer and Parkinson disease.
There are currently studies using stem cells to replaced damaged heart tissue. Further studies are being conducted to treat several types of blood disorders (eg sickle cell anemia, leukemia and certain cancers of the bone marrow) with stem cells.
While the potential for stem cell is enormous, there are legal issues surrounding their use. In many countries, the production of embryonic stem cells is illegal, particularly in Europe and the US. In the USA, one can do research on stem cells but any type of human study requires permission. Further, in the USA one cannot use federal funds to do research on stem cells. At the moment, the use of stem cells to treat medical disease is restricted in the US. Until the ethical and legal challenges are sorted out, stem cell therapy will be limited to the lab the potential for abuse of these cells is enormous and this is the reason why there is caution. One does not want a crazy scientist or government to create a clone of humans for any sinister reasons.

My focus here is not on the immense value of cord blood cells in regenerative medicine but one central ethical issue surrounding the revolutionary science. Whether posthumous or not, the informed consent in issue donation is always a hazy area that is not easy to be governed under regulation. This is because we can’t conclude in legal terms as to who’s the real donor: the mother or her child?

Today, most of the procurement happens only after due consent but the larger question still remains: can this consent be deemed adequate and full-proof in law?  In today’s fast-paced times of invariably strained familial relations, one can’t rule out the possibility of a disputing claim made by a member overriding the mother’s consent. Imagine the complexities it could invite at the door of the clinic long after the donation has been made and utilized for good.

The million dollar (unanswered) question is: who owns the cord? The law is undecided – at times, it assumes the placenta or umbilicus to be part of the mother and in some cases, part of the child. The Genetic argument does favour the child but can’t rule out the claim of family including the father and siblings – both living and future. The logical way out is to make the consent process as inclusive as possible. Which means, rather than assuming things, one should seek the consent of both parents on behalf of their child.

But this is easier said than done. Property rights in human tissue are an unexplored area – both from the judicial and the more important ethical point of view. It’s clearly a long-drawn process of introspection and deliberation and we certainly can’t expect a silver bullet in the form of a solution.

The best we can do NOW is to trigger a global public discussion across all forums – medical or otherwise – on this critical issue that could one day truly unlock the phenomenal potential of this therapeutic stream.