Discovery of the Mechanism by which Stem Cells are Released from Bone Marrow has Vast Implications in Health and Disease

Researchers at Mt. Sinai Hospital in New York have identified the mechanisms that regulate the release of stem cells from bone marrow into the blood. It has long been known that bone marrow-derived stem cells regularly circulate throughout the blood, and many bone marrow transplantation procedures involve the harvesting of stem cells from the peripheral blood. Previously, however, the precise mechanisms by which the stem cells were released into the blood remained unknown. Dr. Paul Frenette and colleagues at the Mt. Sinai School of Medicine have now discovered that molecular adrenergic signals originating in the brain are sent via the sympathetic nervous system directly to “niches” within the bone marrow in which the stem cells reside, thereby triggering the release of the stem cells from these niches into the circulating blood.

The sympathetic nervous system is that part of the autonomic nervous system most commonly identified with the “fight or flight” response, but it is also highly sensitive to stress and is therefore easily activated by changes in circadian rhythms. All species exhibit circadian rhythms that are regulated by a biological “master clock” which in humans is anatomically located in the suprachiasmatic nucleus within the hypothalamus. External cues reset the biological clock daily, the most important one of which is light which stimulates highly photosensitive proteins in the photoreceptors of the retina of the eye from which signals are then transmitted across the retinohypothalamic tract to the suprachiasmatic nucleus which reinterprets the signals and retransmits them to the pineal gland where the hormone melatonin is secreted, and which is known to peak at night. From the hypothalamus through sympathetic nervous system pathways throughout the body, all physiological processes are regulated including cellular metabolism, hormone production, brain wave activity, body temperature, reproduction, and patterns of sleeping and eating, all of which are naturally entrained to the 24-hour cycle of the earth’s rotation.

In this particular study, the Mt. Sinai researchers used a mouse model in which the maximum release of stem cells from the bone marrow into the circulating blood was observed to occur during periods of rest, although changes in light and experimentally induced “jet lag” in the mice were found to alter the patterns of stem cell release. These results are the first to indicate a circadian regulatory relationship between the cyclical “biological clock” and naturally produced endogenous stem cells. The discovery holds many implications for the important role of these rhythmic oscillations in regenerative medicine and also in the natural regeneration that continually occurs in healthy individuals on a daily basis. In patients who need stem cell transplantation, for example, the collection of their own stem cells may be optimized by timing the harvesting of the cells to coincide with those peak hours of release. Additionally, the discovery also highlights the importance of maintaining regular sleeping habits, especially in today’s modern society, since the normal release of stem cells from the bone marrow into the circulating blood may be hindered by such factors as jet lag, sleep deprivation and other disruptions in natural circadian rhythms. The results of this study may offer one of the first concrete scientific explanations for the previously suspected correlation between night shift work and cancer, a causality which has been established by a number of previous studies and formally identified by the World Health Organization as well as by the International Agency for Research on Cancer, which in 2007 listed night shift work as “probably carcinogenic to humans.” A disruption in natural sleeping rhythms which in turn disrupt the peak release times of stem cells from bone marrow into the circulating blood could interfere with the body’s natural ability to repair itself daily and could therefore possibly also contribute to the formation of various types of cancer.

Australian Spinal Cord Research Could Bring New Hope

With the first Australian trial of a new adult stem cell treatment, the hope of improved movement for those with spinal cord injuries has been given a new boost.

In order to coordinate national and international research and apply it to patients, the new dedicated spinal cord laboratory at Melbourne’s St. Vincent’s Hospital. The facility is the first of it’s kind in Australia and will be the location where the trial is conducted.

With no cure in sight and the cost of care at an estimated $1.2 billion, Australia sees a new spinal cord injury every single day.

“This is a major unmet medical need,” said Dr. George Owen, head of Step Ahead Australia, (formerly the Spinal Cord Society of Australia).

After diving into a shallow pool 13 years ago, Dr. Owen’s son Sam became a quadriplegic. Sam is now 26 years old.

New leads into the treatment and possible cure for spinal cord injury may be developed during the trial where scientists will work with a spinal cord

Liver Repaired Using Experimental Stem Cell Drug

After doctors gave a man an experimental stem cell drug, the 20-year-old Abu Dhabi man’s liver repaired itself. He is now fully recovered.

A British scientific journal will publish the treatment results and recovery story of the man along with four others who underwent the same treatment with mixed results.

The man’s liver failed suddenly during treatment for leukemia tow years ago according Singapore based consultant general surgeon Dr. Susan Lim.

“He needed a liver transplant,” she said. “I treated him with the stem cell drug [which her team is studying] and within three days, he woke up,” she added.

After an evaluation by Dr. Lim, the man is considered to be fully recovered and tests show that his liver is functioning normally.

She said that

Stroke Damage Recovery with Adult Stem Cells

A faster and more full recovery is possible when stroke victims are treated with transplanted stem cells according to researchers in China, Canada, and Korea. The studies were conducted with bone marrow stem cells (BMSC) and human mesenchymal stem cells (hMSC).

The cells will travel to blood-deprived and damaged areas of the brain and help repair damage caused by stroke regardless of the site of injection. The two studies were both published in the most recent issue of the journal Cell Transplantation.

The subjects tested “exhibited significant reductions in scar size and cell death and improvements in neurological function when compared to controls that received no BMSCs,” said Ren-Ke Li, MD, PhD, who is the lead author of the joint Canadian-Chinese study.

Cell Transplantation associate editor Cesar V. Borlongan, Ph.D said that

Brittle Bone Disease and Stem Cells

Today an announcement was made that experiments on mice found they suffered fewer bone fractures following treatment with stem cells. Brittle bone disease could be treated in the womb by the stem cell therapy discovered by scientists.

Osteogenesis Imperfecta (OI) is the most common disease causing fractures in childhood, some can even occur in the womb. Experts hope that the discovery will lead the way to similar procedures to remedy this problem in babies.

Collagen is one of the main building blocks for bone, and in OI, it fails to develop properly. Suffers can be left with multiple fractures due to stunted growth and weak bones. By the time they are teenagers, about 50 percent of people suffering from OI find that they have impaired hearing.

Researchers believe the findings could lead to the development of treatments for other diseases including muscular dystrophy. Only one in 10,000 people have OI, so the potential for treating other diseases as well is enticing.

A 14-day-old mouse with OI was given a stem cell transplant by a team at Imperial College London. The cells were derived from fetal blood. Compared to the untreated group of mice, the study revealed that the treated mice sustained a two thirds reduction in long bone fractures.

Another contrast was that the treated mice also developed longer, thicker, and stronger bones.

OI sufferers had fractures that eventually healed but they were left with deformities said Professor Nicholas Fisk who led the study.

“It will help us to understand what it is that leads to such a marked effect after a single transplant of stem cells, so that this can be harnessed to improve the results of stem cell therapy in repairing adult tissues and degenerative conditions,” he said.

“Our work suggests that, in the future, it could be possible to take stem cells from an unborn baby carrying the abnormal OI gene, manipulate them to correct the errant gene, and then put them back into the fetus to allow it to develop properly.”

“We only need to collect 100 or 200 microlitres of blood from the fetus, which is a tiny amount, less than a fifth of a milliliter of blood. From this tiny sample we can grow all that we need to provide the potential treatment.”

“However, with further work we should be able to gain the stem cells we need from amniotic fluid or the placenta; thereby removing any potential risk of drawing fetal blood.”

The two thirds reduction was called “extraordinary” by Professor Fisk, but he said it was not a cure. 60 percent of all the mice still had some sort of fracture, and baby mice still had an average of one fracture each.

Dr. Yolande Harley, of charity Action Medical Research, which funded the project, said: “Professor Fisk’s work is a real breakthrough. It suggests that if stem cells could be successfully transplanted before a baby with OI is even born, it could mean a significant improvement in the child’s health and quality of life.”

“This is a tremendous piece of work that could have implications for many more diseases and conditions.”

Heart Failure Recovery Boosted by Stem Cells

The administration of adult bone marrow stem cells (BMC) and mesenchymal stems cells (MSC) can aid in the recovery of myocardial infarction (MI) – commonly known as heart attack – and consequently increase survival rates according to a study in the Clinical and Experimental Pharmacology and Physiology published by Wiley-Blackwell.

The study is designed to evaluate the impact of systemic delivery of BMC and MSC on spontaneously hypertensive rats induced with MI.

Dr. Nardi, the lead author of the study called,

Stem Cell Heart Trial Receives Approval

Millions of heart attack patients could have their chances of survival boosted and quality of life improved when British surgeons begin their ground-breaking research next month.

During bypass operations, stem cells will be injected into the hearts of patients. The procedures will be carried out by a team at Bristol University.

Earlier this week, The Human Tissue Authority gave Raimondo Ascione, the surgeon leading the research, approval to carry out the trial.

This will be the first large-scale trial comparing patients given the treatment with those given placebo injections, and previous smaller studies have already provided hope that this approach could provide a breakthrough.

Usually because the arteries supplying the heart with blood become blocked with fatty deposits, the heart muscle is starved of oxygen and a heart attack can take place.

Scar tissue can be left behind that no longer contributes to pumping the blood around the body after a bypass operation which is designed to restore the blood supply.

The new study will test the effectiveness of stem cell injections in repairing these scars in patients who have had acute large heart attacks – in which the scarring penetrates more than halfway through the thickness of the heart wall.

Mr. Ascione said yesterday: “We expect that after six months we will have been able to reduce or even make the scars disappear completely.

Dying Legs Treated with Human Stem Cells

With the hope of growing small blood vessels and restoring circulation in the legs, two patients were the first to be treated by transplanting a purified form of the subjects’ own adult stem cells into the leg muscles. Both patients suffered from severely blocked arteries and faced possible leg amputations. This first U.S. trial of the technique that has worked on laboratory animals was conducted by Northwestern University Feinberg School of Medicine.

“They’re at the end of the therapeutic road and they’re ultimately facing potential amputation,” said Douglas Losordo, M.D., the Eileen M. Foell Professor of Heart Research and principal national investigator for the study. “This is hopefully a way to help them avoid that.”

Losordo is director of the university’s Feinberg Cardiovascular Research Institute and director of cardiovascular regenerative medicine at Northwestern Memorial Hospital.

“The stem cells themselves can assemble into blood vessels,” Losordo said. “They can also secrete growth factors that stimulate and recruit other stem cells to come into the tissue and help with the repair. It’s an amazing biology we’re trying to leverage in these folks.”

The approach has proven to be effective in mice and rats during pre-clinical studies where stem cells were transplanted into the limbs of the animals.

“Based on that, we think it has a good chance of helping humans,” Losordo noted.

“This is a dreadful disease in which the profession has failed to offer much in the way of relief for these patients,” Losordo said. “We’re hoping this will have some impact.”

The trial is being conducted at 20 different sites nationally. The first two patients received their transplants at Northwestern Memorial Hospital.

Wounds that don’t heal, the breakdown of tissue, and gangrene can be the result of severely blocked arteries in the leg and sharply diminished blood flow. More than 100,000 limbs are amputated in the United States due to the painful condition call critical limb ischemia (CLI).

Affecting 1.4 million people, the emerging health problem is serious. By the time they reach the age of 70, and estimated 15 percent of the population will suffer from this disease.

Patients who have exhausted all other medical options including angioplasty, stents and bypass surgery to repair blocked circulation in their legs were the target of the Northwestern-led phase I/IIa study, which will include 75 people with CLI around the country.

Affecting about 10 million people in the United States, critical limb ischemia is the result of advanced peripheral artery disease. In peripheral artery disease, people develop blockages in their arteries and vessels that slow or stop the blood flow to their legs.

The condition is called CLI when they have wounds on their legs or feet that will not heal and pain at rest in their lower legs. If left untreated, CLI can result in a patient having toes, a foot or even a leg amputated.

People begin to experience pain when they walk, then when just sitting, as CLI progresses. Since blood flow decreases when people lie down, the pain is the worst at night. In order to lessen the pain and aid in blood flow, some even sleep in chairs.

“Peripheral artery disease is a big health problem,” Losordo said. “There is an emerging awareness of this disease on public health.”

The risk of developing the condition is elevated by high blood pressure, diabetes, high cholesterol and smoking.

However, Losordo points out that, “some people don’t smoke, have diabetes or high blood pressure and can still have blocked arteries in their legs.”
Losordo uses the subject’s own purified stem cells for the randomized, double blind, placebo-controlled trial. CD34+ stem cell from bone marrow are first released into the blood stream by a stem cell stimulating drug. The patient takes this drug for five days prior to the stem cell extraction. Then, the CD34+ enriched blood is obtained by way of an intravenous line that is inserted into a subject’s vein to collect blood through a machine that removes a population of blood cells. Losordo further selects and enriches the cells to select only CD34+ cells.

Heart Treatment with iPS Cells – Joint Japanese Research

In order to treat heart disease, induced pluripotent stem cells or iPS cells will be used in a joint study by two professors from Osaka and Kyoto university.

The joint research will be conducted by Osaka University Professor Yoshiki Sawa, who has treated heart disease using cell sheets created from muscle, and Kyoto University Professor Shinya Yamanaka, who created iPS cells that can develop into various types of cells, such as organ or tissue cells, from ordinary human skin.

Cardiac muscle regeneration treatment is the focus of their research.

Yamanaka will be the leader of a newly established iPS cell research center at Kyoto University. The announcement was made on Tuesday.

Using human thigh muscle, Sawa and his research team created cell sheets last year. The heart function of a patient who was a heart transplant candidate was improved when the cell sheets were attached to an area around the heart.

Sawa hopes to turn iPS cells into cardiac muscle cells since the cell sheets do not change into cardiac muscle. He hopes to apply the new research findings to the treatment.

Sawa said, “I’d like to create new cell sheets from new materials using iPS cells, make the sheets available in many cases and enhance the sheets’ practicality.”

The planned research center will be part of the Institute for Integrated Cell-Material Sciences, a world-class research institution that opened in October in Kyoto University.

Several institutions including Kyoto’s University’s Institute for Frontier Medical Sciences will help staff the center with several part-time teams of researchers. The center will also be comprised of a full-time team of 10 to 20 professors, associate professors, researchers and engineers.

The researchers are aiming to develop a safer method of creating iPS cells while sharing their research results. Studying technologies to turn iPS cells into cells for particular purposes is also on the agenda.

Yamanaka said at a press conference on Tuesday that he hoped the planned center would be a research facility open to researchers around the world covering basic to clinical medicine.

“I’d like to nurture young researchers because iPS research requires 10 to 20 years of effort,” he said.

A private incubation facility in Shimogyo Ward, Kyoto, will temporarily host the center in a research lab at the Kyoto Research Park.

Japanese Stem Cell Research Surges

With the intent of guiding Japan back to leadership in the field of biotechnology, the Koizumi government adopted a new strategy six years ago.

This did not mark the first time that a national policy initiative of this type was put into effect. And as the current administration tries to capitalize on an exciting stem cell breakthrough, Japan is on the verge of another.

Leading countries have surpassed Japan since 2002.

Japanese biotech drug development, as a ratio of overall drug development, lagged the US, Britain, France and Germany by about 50 per cent according to a report published last year by The Office of Pharmaceutical Industry Research.

Though it is generalization that doesn’t sit convincingly with the nation’s international scientific patents, or Nobel Prize winners over the past 20 years, the disappointing performance in applied biotechnology is often attributed to Japanese science’s alleged weakness at radical innovation.

However, it goes some way towards explaining the surge of official optimism that has built up behind Shinya Yamanaka’s induced pluripotent stem (iPS) cell research team at Kyoto University’s Institute of Frontier Medicine.

It remains to be demonstrated, however, that ministers and officials understand their contribution to previous shortcomings: ponderous and intrusive forms of regulation and administrative guidance that hobble Japanese scientists in the rapidly moving areas of medical and biological R&D.

In the late 1980’s, because of the countries excellence in science education, a high level of government commitment, and track record of converting research into commercial and clinical innovation, Japan was widely expected to become the dominant nation in the exciting new field of biotechnology even at senior policy levels in the US.

Intense bureaucratic supervision usually accompanies a high level of official commitment to an undertaking in Japan, and this is one reason why the biotechnology revolution did not take off in Japan as predicted.

Stem cell research programs can wait 12 months for government approvals, and once under way, pharmaceutical and biotech companies complain, grant-funded research is inflexibly administered.

Approval procedures are far lengthier than in the US and most other Western countries for new drugs and clinical procedures.

However, a fantastic door to opportunity for Japanese leadership has been opened by iPS cell research.

The Yamanaka team’s work seems to have signposted the path to the summit of biotechnology: stem cell therapy with its enormous promise to treat conditions such as Parkinson’s, diabetes, heart and spinal cord damage – but unencumbered by the ethical difficulty of using cloned human embryos or eggs to create embryonic stem cells.

The use of four genetic “transcription factors” to successfully reprogram mice skin cells into becoming stem cells was announced by Yamanaka in June. Another team from the University of Wisconsin was able to produce human iPS cells in November. Not long after, Yamanaka’s group succeeded in making iPS cells using only three transcription factors.

Since the gene c-myc can often cause tumors, they omitted it from the other four.

National admiration has risen for Yamanaka and the world’s attention as focused on the rush of innovation.

But almost invariably, a glum recitation of previous shortfalls in Japanese biotech comes out of what begins as news of further advances in the science or more government support for developing the technology.

The reason is not difficult to see.

Japan imposes the heaviest regulatory conditions of any country that permits embryonic stem cell research. So it is not difficult to at least partially understand why Yamanaka moved into iPS research.

He has complained about the Government’s “terrible regulations and crazy policies that crush any long-term projects”.

Other aspects of the iPS discovery have reached another breakthrough point said Yamanaka in an interview with Tokyo reports last week. However, stem cell therapy is still years away from clinical application he said.

“The other applications, like toxicology and drug development, it’s ready to go,” he said.

“We can use iPS cells in these applications today, if somebody can pay a lot of money – like pharmaceutical companies.”

Those applications involve using iPS cells to create, for instance, neural cells outside someone’s body so they can be tested for personal disease factors, or for an exactly tailored drug treatment.

An immediate start to