It has always been understood, at least intuitively if not scientifically, that physical exercise is important for proper health, mentally as well as physically. Indeed, a number of previous studies have indicated that people who engage in regular physical exercise score higher on memory tests than people who do not exercise. Now, researchers at Columbia University have shed some light on the specific mechanisms that are at work in the mental benefits that result from physical exercise.

Physical exercise targets a region within the hippocampus that is known as the dentate gyrus, a specialized region of the brain which is involved in memory, among other neurological processes. When the neurons of the dentate gyrus begin to atrophy over the years, the person is said to suffer age-related memory decline. Conversely, the growth of new neurons within the dentate gyrus will prevent memory decline – and this is exactly what happens as a result of physical exercise. Using MRI (magnetic resonance imaging), the researchers at Columbia University have now revealed that neurogenesis (the growth of new neurons) is stimulated in the dentate gyrus region immediately following physical exercise. These new nerve cells provide protection against the loss of memory with age.

In the past, prior to MRI technology, neurogenesis was observable only via postmortem examination, from which it was found that age-related memory decline typically begins around 30 years of age. However, the onset of memory decline was associated with this age only because this has traditionally been the stage of life at which people tend to become more habitually sedentary in their lifestyles, and less inclined toward serious physical exercise. By contrast, by prolonging regular physical exercise throughout life, neurogenesis in the dentate gyrus can continue up to any age. According to Scott Small, M.D., associate professor of neurology at Columbia University Medical Center, a research scholar at the Columbia University Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, and the principal investigator of the study, “I, like many physicians, already encourage my patients to get active and this adds yet another reason to the long list of reasons why exercise is good for overall health. Our next step is to identify the exercise regimen that is most beneficial to improve cognition and reduce normal memory loss, so that physicians may be able to prescribe specific types of exercise to improve memory.”

The Taub Institute for Research on Alzheimer’s Disease and the Aging Brain at Columbia University Medical Center is focused on the prevention and cure of Alzheimer’s disease, Parkinson’s disease and other age-related brain diseases. Fred Gage, Ph.D., of the Salk Institute in California, and a co-investigator in the study, had previously demonstrated in mice that exercise stimulates neurogenesis in the dentate gyrus, but this is the first concrete evidence of such exercise-related neurogenesis in the dentate gyrus of humans.

Researchers at Kansas State University have developed a new drug delivery system for cancer patients which is more effective and has less side effects than standard chemotherapy. According to Dr. Deryl Troyer, professor of anatomy and physiology at the Kansas State College of Veterinary Medicine, “Although chemotherapy has saved many lives, it often has undesirable side effects. The people most excited about this research are people who have gone through chemo, because our approach may circumvent many of those side effects.”

As part of the Midwest Institute for Comparative Stem Cell Biology, Dr. Troyer and his colleagues have received a $380,000 grant from the National Institutes of Health to study the mechanisms by which the natural homing properties of stem cells may be harnessed to transport anti-cancer drugs directly into breast cancer cells via nanoparticles. The techniques have been developed in vitro and preclinical trials are being planned. The scientists have isolated the stem cells from Wharton’s jelly, which is the gelatinous substance found inside the umbilical cord. As Dr. Troyer explains, “Billions and billions of these cells are disposed of every day. We think these cells have a lot of advantages, including their ability to be harvested in large numbers very rapidly. We are using these cells as stealth vehicles.” Because stem cells have a natural ability to target tumors, the scientists are utilizing the stem cells as delivery systems for nanoparticles that contain the anti-cancer drugs. More specifically, the drugs are loaded into specially designed nanogels that are comprised of two polymers. According to Dr. Duy Hua, a professor of chemistry at K-State, “The nanogel can be viewed as a very tiny piece of paper that wraps around the anti-cancer drug like a candy wrapper. Over time or under certain conditions, the paper unwraps and releases the candy. Most anti-cancer drugs, including ours, are insoluble in water. However, the nanogel is water soluble.” As Dr. Troyer adds, “Many potent small-molecule drugs are sitting on a shelf collecting dust. Often they are insoluble or have many toxic effects. We hope to deliver some of these compounds in a more targeted manner via the combination of stem cells and nanoparticles. Although nanotechnology has made enormous strides toward more focused drug delivery, there is always room for improvement.”

Once it has undergone the usual testing in preclinical and clinical trials, such a novel therapy is expected to offer a preferable alternative, both financially and medically, to chemotherapy and its numerous side effects.

While a ten-year-old Australian Shepherd suffers with advanced arthritis that is most pronounced in the hips and elbows, the owners of the dog weigh all the pragmatic considerations of the various medical options that are available. At a total cost of $2,500, stem cell therapy is an appealing alternative to joint replacement, which costs approximately $5,000 per joint and which, until now, has been the only other type of therapy that was available for the most severe of arthritic conditions. Additionally, joint replacement often requires a long convalescence period, as much as six months or longer, while stem cell therapy has been shown to yield noticeable improvement almost immediately.

“Vet Stem Regenerative Cell” (VSRC) therapy is becoming increasingly common in the treatment of age-related arthritis as well as tendon and ligament injuries in domestic animals such as dogs and cats. The VSRCs are derived from the animal’s own fat, and as such these stem cells are readily and conveniently available from each animal. According to Jeff Peck, D.V.M., of the Affiliated Veterinary Specialists in Orlando, Florida, “It’s not from an embryo and it’s not from bone marrow. It’s taken from fat and that’s one of the huge advantages of it because, number one, you always have a donor.” After being isolated from the fat, the stem cells are injected directly into the afflicted joints of the animal, often with signs of immediate improvement. Six weeks after receiving the stem cell therapy, the ten-year-old Australian Shepherd who was previously unable to lay down or stand up without moaning in pain is now able to leap comfortably. Similar therapies are being translated into applications for people.

Human beings and their canine companions have enjoyed a long and ancient friendship, as both species have evolved together from prehistoric times, each learning to assist the other in their daily survival. The modern field of regenerative medicine and stem cell therapy would now appear to be the latest chapter in this ongoing partnership.

Researchers at the Harvard-affiliated Joslin Diabetes Center in Boston have announced an improvement in mice afflicted with the Duchenne form of muscular dystrophy following treatment with adult stem cells. The results of the study demonstrate for the first time that skeletal muscle precursor cells are capable of repairing muscle tissue and thereby of restoring function in this particular form of muscular dystrophy.

According to Dr. Amy Wagers of the Joslin Section on Developmental and Stem Cell Biology, who is also Assistant Professor of Stem Cell and Regenerative Biology at Harvard University and principal faculty member at the Harvard Stem Cell Institute, “This study indicates the presence of renewing muscle stem cells in adult skeletal muscle and demonstrates the potential benefit of stem cell therapy for the treatment of muscle degenerative diseases such as muscular dystrophy.”

As the world’s largest diabetes research center, the Joslin Diabetes Center employs the world’s most extensive team of board-certified physicians who are actively involved in the treatment of diabetes, with current research encompassing stem cell therapies and applications to other diseases such as muscular dystrophy. Duchene is the most common form of muscular dystrophy, which is caused by a genetic mutation and characterized by rapid muscular degeneration. Previously, all forms of muscular dystrophy have been considered incurable, as standard medicine offers no known safe or effective treatment. Adult stem cell therapy, however, now provides a new modality for the treatment of this disease.

As Dr. Wagers explains, “Once the healthy stem cells were transplanted into the muscles of the mice with muscular dystrophy, they generated cells that incorporated into the diseased muscle and substantially improved the ability of the treated muscles to contract. At the same time, the transplantation of the healthy stem cells replenished the formerly diseased stem cell pool, providing a reservoir of healthy stem cells that could be re-activated to repair the muscle again during a second injury. This work demonstrates, in concept, that stem cell therapy could be beneficial for degenerative muscle diseases.”

Dr. Wagers and her colleagues are focused on studying the cellular mechanisms that regulate migration, expansion and the regenerative potential of hematopoietic as well as skeletal muscle stem cells. Thus far, the cells have proven to offer not only immediate regeneration to damaged tissue but also a reserve pool of cells that provide continuous regeneration and maintenance of the muscles throughout the future life of the muscles.

Imagine a general purpose drug, available to everyone everywhere, which may be bought “off the shelf”, yet which has the natural ability to custom-tailor its efficacy according to the specific needs of each individual patient. Such is the objective of the Indian stem cell company Stempeutics.

Associated with Manipal University and Manipal Hospital outside of Bangalore, but with laboratories in Bangalore and Malaysia, Stempeutics is developing adult stem cell therapies for a vast range of diseases, as most stem cell companies throughout the world are doing today. What sets Stempeutics apart from most others, however, is its design of a stem cell therapy which is not disease-specific, but which is available “off the shelf” and may be used by patients with dissimilar diseases. According to B.N. Manohar, President of Stempeutics, “If a drug that can be stocked and delivered can be made of stem cells, it will bring down the cost of therapy dramatically.”

Throughout the world, specific stem cell therapies are usually administered to patients with specific diseases, yet scientists have already demonstrated certain universal properties of some stem cells which potentially allow for the therapeutic applicability of the cells in a generic sense. It is known, for example, that the differentiation of stem cells into various types of tissue may be regulated by a number of mechanisms which include internal controls such as genetic directions, and external controls such as damaged tissue to which the stem cells automatically migrate. Directed by these various regulating cellular and genetic control mechanisms, therefore, the same collection of stem cells could administered to different patients for different purposes in the treatment of different diseases.

Stempeutics is focused exclusively on the use of adult stem cells, specifically, mesenchymal stem cells, which are “immune privileged” and do not require matching between the donor and recipient. The new therapies have already been tested on several patients with diverse diseases, all of whom are showing improvement.

The company Pfizer is funding the creation of a new biotech company in San Diego called EyeCyte, specifically for the development of a new type of adult stem cell therapy that is targeted for eye diseases.

Dr. Martin Friedlander, an ophthalmologist at the Scripps Research Institute, has identified stem cells in the blood and bone marrow that are capable of repairing damaged blood vessels in the eyes of animals. According to Dr. Friedlander, he has already been able to cure mice in his laboratory by using these stem cells, in research which was funded by the National Eye Institute. When he decided to start a new biotech company that would develop and commercialize such a therapy for humans, rather than pursue the ordinary venture capital route he chose to seek funding directly from Pfizer instead. According to Corey Goodman, president of Pfizer’s biotech unit, “Pfizer has put its flag in the ground that there is a future in regenerative medicine. The eye is a very good place to be starting – it is an isolated organ and there is a huge need.” In April of this year, Pfizer had already initiated a new department for regenerative medicine that was focused on the development of stem cells, and now Pfizer’s top scientists are collaborating with Dr. Friedlander and his colleagues. Thus far Pfizer has committed $3 million to launching the new company, with the right of first refusal to buy the company in a few years if it proves to be successful.

In humans, retinal damage if often the result of diseases such as diabetes and age-related macular degeneration, both of which result in the formation of abnormal blood vessels. Diabetic retinopathy is especially common in certain developed countries such as the U.S., but until now it has only been treatable with laser therapy, the purpose of which is to kill the damaged retinal cells. Now stem cells offer the first type of treatment that can actually repair damaged blood vessels and restore proper blood flow. According to Mohammed El-Kalay, a chief executive at EyeCyte, their first human trials are expected to begin in approximately 3 years. This type of stem cell therapy would compete with drugs such as Lucentis, developed by Genentech, which is currently approved for macular degeneration and is also being tested for diabetic eye disease.

EyeCyte’s therapy strictly uses only the adult stem cells known as CD44, which are injected directly into the afflicted eye. With such a therapy, in the future it would be possible for a patient to visit the doctor in the morning, at which time a blood sample would be drawn from which the CD44 adult stem cells would be isolated, and then the patient would return in the afternoon for an injection into the eye of his or her own autologous purified stem cells, which would heal the damaged blood vessels as well as protect against further damage.