Stem Cell Clinic

Medical Experts Call for Tighter Controls on Stem Cell Tourism – Voice of America

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Stem cell tourism involving patients who travel to developing countries for treatment with unproven and potentially risky therapies should be more tightly regulated, international health experts said Wednesday.

With hundreds of medical centers around the world claiming to be able to repair damaged tissue in conditions such as multiple sclerosis and Parkinson's disease, tackling unscrupulous advertising of such procedures is crucial, the experts said.

These therapies are advertised directly to patients with the promise of a cure, but there is often little or no evidence to show they will help, or that they will not cause harm, the 15 experts wrote in the journal Science Translational Medicine.

Some types of stem cell transplant mainly using blood and skin stem cells have been approved by regulators after full clinical trials found they could treat certain types of cancer and grow skin grafts for burns patients.

But many other potential therapies are only in the earliest stages of development and have not been approved by international regulators.

"Stem cell therapies hold a lot of promise, but we need rigorous clinical trials and regulatory processes to determine whether a proposed treatment is safe, effective and better than existing treatments," said one of the 15, Sarah Chan of Britain's University of Edinburgh.

The experts called for global action, led by the World Health Organization, to introduce controls on advertising and agree on international standards for the manufacture and testing of cell- and tissue-based therapies.

"The globalization of health markets and the specific tensions surrounding stem cell research and its applications have made this a difficult challenge," they wrote. "However, the stakes are too high not to take a united stance."

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Medical Experts Call for Tighter Controls on Stem Cell Tourism - Voice of America

Smelling your food makes you fat – UC Berkeley

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Our sense of smell is key to the enjoyment of food, so it may be no surprise that in experiments at the University of California, Berkeley, obese mice who lost their sense of smell also lost weight.

Whats weird, however, is that these slimmed-down but smell-deficient mice ate the same amount of fatty food as mice that retained their sense of smell and ballooned to twice their normal weight.

In addition, mice with a boosted sense of smell super-smellers got even fatter on a high-fat diet than did mice with normal smell.

The findings suggest that the odor of what we eat may play an important role in how the body deals with calories. If you cant smell your food, you may burn it rather than store it.

These results point to a key connection between the olfactory or smell system and regions of the brain that regulate metabolism, in particular the hypothalamus, though the neural circuits are still unknown.

This paper is one of the first studies that really shows if we manipulate olfactory inputs we can actually alter how the brain perceives energy balance, and how the brain regulates energy balance, said Cline Riera, a former UC Berkeley postdoctoral fellow now at Cedars-Sinai Medical Center in Los Angeles.

Humans who lose their sense of smell because of age, injury or diseases such as Parkinsons often become anorexic, but the cause has been unclear because loss of pleasure in eating also leads to depression, which itself can cause loss of appetite.

The new study, published this week in the journal Cell Metabolism, implies that the loss of smell itself plays a role, and suggests possible interventions for those who have lost their smell as well as those having trouble losing weight.

Sensory systems play a role in metabolism. Weight gain isnt purely a measure of the calories taken in; its also related to how those calories are perceived, said senior author Andrew Dillin, the Thomas and Stacey Siebel Distinguished Chair in Stem Cell Research, professor of molecular and cell biology and Howard Hughes Medical Institute Investigator. If we can validate this in humans, perhaps we can actually make a drug that doesnt interfere with smell but still blocks that metabolic circuitry. That would be amazing.

Riera noted that mice as well as humans are more sensitive to smells when they are hungry than after theyve eaten, so perhaps the lack of smell tricks the body into thinking it has already eaten. While searching for food, the body stores calories in case its unsuccessful. Once food is secured, the body feels free to burn it.

After UC Berkeley researchers temporarily eliminated the sense of smell in the mouse on the bottom, it remained a normal weight while eating a high-fat diet. The mouse on the top, which retained its sense of smell, ballooned in weighton the same high-fat diet.

The smell-deficient mice rapidly burned calories by up-regulating their sympathetic nervous system, which is known to increase fat burning. The mice turned their beige fat cells the subcutaneous fat storage cells that accumulate around our thighs and midriffs into brown fat cells, which burn fatty acids to produce heat. Some turned almost all of their beige fat into brown fat, becoming lean, mean burning machines.

In these mice, white fat cells the storage cells that cluster around our internal organs and are associated with poor health outcomes also shrank in size.

The obese mice, which had also developed glucose intolerance a condition that leads to diabetes not only lost weight on a high-fat diet, but regained normal glucose tolerance.

On the negative side, the loss of smell was accompanied by a large increase in levels of the hormone noradrenaline, which is a stress response tied to the sympathetic nervous system. In humans, such a sustained rise in this hormone could lead to a heart attack.

Though it would be a drastic step to eliminate smell in humans wanting to lose weight, Dillin noted, it might be a viable alternative for the morbidly obese contemplating stomach stapling or bariatric surgery, even with the increased noradrenaline.

For that small group of people, you could wipe out their smell for maybe six months and then let the olfactory neurons grow back, after theyve got their metabolic program rewired, Dillin said.

Dillin and Riera developed two different techniques to temporarily block the sense of smell in adult mice. In one, they genetically engineered mice to express a diphtheria receptor in their olfactory neurons, which reach from the noses odor receptors to the olfactory center in the brain. When diphtheria toxin was sprayed into their nose, the neurons died, rendering the mice smell-deficient until the stem cells regenerated them.

Separately, they also engineered a benign virus to carry the receptor into olfactory cells only via inhalation. Diphtheria toxin again knocked out their sense of smell for about three weeks.

In both cases, the smell-deficient mice ate as much of the high-fat food as did the mice that could still smell. But while the smell-deficient mice gained at most 10 percent more weight, going from 25-30 grams to 33 grams, the normal mice gained about 100 percent of their normal weight, ballooning up to 60 grams. For the former, insulin sensitivity and response to glucose both of which are disrupted in metabolic disorders like obesity remained normal.

Mice that were already obese lost weight after their smell was knocked out, slimming down to the size of normal mice while still eating a high-fat diet. These mice lost only fat weight, with no effect on muscle, organ or bone mass.

The UC Berkeley researchers then teamed up with colleagues in Germany who have a strain of mice that are supersmellers, with more acute olfactory nerves, and discovered that they gained more weight on a standard diet than did normal mice.

People with eating disorders sometimes have a hard time controlling how much food they are eating and they have a lot of cravings, Riera said. We think olfactory neurons are very important for controlling pleasure of food and if we have a way to modulate this pathway, we might be able to block cravings in these people and help them with managing their food intake.

Co-authors of the paper are Jens Brning, director of the Max Planck Institute for Metabolism Research in Cologne, Germany, and his colleagues Eva Tsaousidou, Linda Engstrm Ruud, Jens Alber, Hella Brnneke and Brigitte Hampel; Jonathan Halloran, Courtney Anderson and Andreas Stahl of UC Berkeley; Patricia Follett and Carlos Daniel de Magalhaes Filho of the Salk Institute for Biological Studies in La Jolla, California; and Oliver Hahn of the Max Planck Institute for Biology of Ageing in Cologne.

The work was supported by the Howard Hughes Medical Institute, the Glenn Center for Research on Aging and the American Diabetes Association.

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Smelling your food makes you fat - UC Berkeley

These Scientists Have a Plan To Cheat Death. Will It Work? – NBCNews.com

Resurrecting the dead may be out of the question, but new research points to better ways to care for patients with critical brain injuries.Jun.29.2017 / 4:32 PM ET Conceptual close up image of a synapse. Science Picture Co / Getty Images Conceptual close up image of a synapse. Science Picture Co / Getty Images

Nothing is as certain as death. Yet humans have come up with ways to push it further and further. The heart stops beating? Do CPR. The lungs fail? Use a mechanical ventilator. These techniques have saved the lives of millions. There is a point of no return, however: when the brain dies.

One company, Philadelphia-based Bioquark Inc., thinks it may be possible to push back on even that last step. Bioquark plans to launch a study to use stem cells and a slew of other therapies to bring a glimmer of life back to the dead brains of newly deceased patients.

The idea led to hundreds of chilling headlines and has met serious backlash from scientists and ethicists alike. While Bioquarks proposed study may trigger ethical and practical concerns, experts do say advances in stem cell research and medical technologies mean someday brain injury could be reversible. Maybe (and thats a big maybe) brain death wont be the end of life.

I agree stem cell technology in the neurosciences has tremendous potential, but we have to study it in a way that makes sense, said Dr. Diana Greene-Chandos, assistant professor of neurosurgery and neurology at Ohio State University Wexner Medical Center. What doesnt make sense, she says, is to apply stem cell research in complex human brainsvery damaged onesbefore animal studies have gotten far enough.

Thats why Bioquarks proposed study, slated to take place in South America sometime this year, has caused such uproar in the science community. The team plans to administer therapies to 20 brain-dead subjects with the hope of stirring up electrical activity in the brain. The idea is to deliver stem cells to the brain and coax them to grow into new brain cells, or neurons, with the help of a nurturing peptide cocktail, electrical nerve stimulation, and laser therapy.

Related: Godlike 'Homo Deus' Could Replace Humans as Tech Evolves

We are employing this [combined] approach, using tools that by themselves have been employed extensively, but never in such an integrated process, said Bioquark CEO Ira Pastor.

One critique is that such a study could give false hope to families who may have a poor understanding of the severity and irreversibility of brain death, and confuse it with coma or vegetative state. There are a lot of gray areas in medicine. And we should all keep an open mind. But we need to make sure we are not misguiding our patients, said Dr. Neha Dangayach, attending physician in the neurosurgical intensive care Unit at New Yorks Mount Sinai Hospital.

Pastors response to the criticism? The public is catching up to the idea of brain death. Hes also clarified that full resurrection is not the companys intended goalat least not yet. We are not claiming the ability to erase death. We are working on a very small window, a gray zone between reversible coma and death, he said.

Ethics aside, critics say there are practical problems with the plan. There is insufficient evidence behind Bioquarks approach, they argue, and the way the study is planned does not sound realistic.

When the brain dies, inflammation and swelling run amok, the connections between neurons disintegrate, arteries collapse, and blood flow shuts down. Once someone is brain-dead, you can keep them on the ventilator but its very hard to keep the organs from shutting down and the heart beating for more than a few days, said neurologist Richard Senelick. Nature is going to run its course.

So, many scientists say Bioquarks study may be a quixotic queston par with cryogenic brain preservation and head transplants. They may sound good in theory but are so impractical that they have little chance of success. Nevertheless, experts agree the quest does raise serious questions that deserve answers. Just what would it take to save a brain? Perhaps resurrecting dead brains is not in the realm of possibilitybut what is?

There is an immense reward in pursuing brain regeneration. If it pans out, it could potentially save the lives of those who are injured in an accident or, more commonly, suffer extreme brain damage following a cardiac arrest or stroke. Every year in the United States, about 350,000 people experience an out-of-hospital cardiac arrest, according to the American Heart Association. Only about 10 percent survive with good neurologic function. Another 130,000 people die of stroke annually.

To appreciate the challenge of saving the brain, first look at what it takes to kill it. It was long thought that death occurs when the heart stops. Now we know that death actually happens in the brainand not in one single moment, but several steps. A patient lying in a coma in an intensive care unit may appear peaceful, but findings from biochemical studies paint a much different scene in his brain: fireworks at the cellular level.

When neurons encounter a traumatic event, like lack of blood flow after cardiac arrest, they go into a frenzy. Some cells die during the initial blackout. Others struggle to survive in the complex cascade of secondary injury mechanisms, triggered by the stress of being deprived of oxygen. Neurotransmitters spill out of neurons in high concentrations. Free radicals pile up, burning holes in brain cell membranes. The pierced cells respond to the attack by producing more inflammation, damaging other cells.

Eventually, the stress response triggers apoptosis, or the process of programmed cell death. In other words, the cells suicide switch gets turned on. The cells die one by one until the brain ceases to function.

Thats brain death: the complete and irreversible loss of function of the brain. Doctors determine brain death by checking whether the patient's pupils react to light, whether he responds to pain, and if his body tries to breathe or has retained any other vital function of the brainstem, the part most resilient to injury.

We have strict tests, because its a very serious questionthe question of distinguishing life from death, Dangayach said.

For brain damage at a much smaller scale, however, the situation could be manageable. Cutting-edge therapies are focused on this possibility.

Related: Three Myths About the Brain (That Deserve To Die)

Stem cells have brought an exciting potential opportunity to the grim area of treating brain injury. Currently, theres no FDA-approved stem cell-based therapy for brain problems, and experts suggest staying away from any clinic that offers such therapies. But that doesnt stop researchers from being excited about the possibilities. Unlike in other parts of the body, cells lost in the brain are gone forever. Could stem cells replace them?

That's a reasonable thing to ask, neurologist Dr. Ariane Lewis of New York University said. Lewis is a strong critic of Bioquarks approach, saying that the study borders on quackery, but she thinks stem cell research is promising for stroke recovery. We have little evidence right now, and this is not a commonly employed therapy, but its a research question.

Two regions in the adult brain contain stem cells that can give rise to new neurons, suggesting the brain has a built-in capacity to repair itself. Some of these cells can migrate long distances and reach the injury site.

In some injuries, the brain produces biological factors that stimulate stem cells. Researchers are working to identify those factorswith the aim of someday translating the findings into new drugs to boost a patient's own stem cells.

If we can identify factors that stimulate these cells we could directly repair [the brain], said Dr. Steven Kernie, chief of pediatric critical care medicine at New York Presbyterian Hospital, who is working on this research.

Other teams have been working on turning different types of brain cells into neurons. A team at Penn State University developed a cocktail of molecules that can convert glial cells, a type of brain cell, into functioning neurons in mice. The cocktail of molecules could be packaged into drug pills, the researchers said, perhaps one day taken by patients to regenerate neurons.

Another option: transplant new neurons into the brain. In a 2016 study, scientists successfully transplanted young neurons into damaged brains of mice. A real-life injury in the human brain is a much messier situation than a clear-cut lesion made in the lab. But eventually, such advances may translate into techniques to repair stroke damage.

Related: These Brain Boosting Devices Could Give Us Intelligence Superpowers

For diseases like Parkinsons, in which a particular population of neurons is lostas opposed to widespread indiscriminate damagethere have been several clinical trials with many more slated. Scientists in Australia are using brain cells of pigs as a substitute for lost neurons. Later this year, a Chinese clinical trial will implant young neurons derived from human embryonic stem cells into brains of Parkinsons patients. And five more groups are planning similar trials over the next two years, Nature reported.

Approaches taken in Parkinsons trials may be the most biologically plausible, Kernie said. If these trials are successful, they may pave the way for more widespread application of stem cells for treating brain diseases. Its not proven yet that it will work, but its something that's on the horizon.

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These Scientists Have a Plan To Cheat Death. Will It Work? - NBCNews.com