To Burn Fat, You Could Exercise … or Shiver.


In the bleak midwinter, here’s a warming thought: All that shivering might be getting you in shape.

According to a new study, 15 minutes in the cold can be the metabolic equivalent of an hour of exercise. Both have an impact on our two main types of adipose tissue, aka fat.

Members of the Coney Island Polar Bear Club dry off after swimming at the beach at Coney Island.

White fat—the blobby kind that bulges hips, thighs, and bellies—stores energy. Brown fat—prevalent in infants but less abundant in adults—generates heat and burns calories when stimulated.

Last year scientists at the U.S. National Institutes of Health monitored ten healthy adult subjects—a mix of men and women—as they exercised in a 65°F (18°C) lab. Later the same subjects lay on a bed as the temperature fell to a shiver-inducing 53°F (12°C).

In both tests the subjects’ muscles contracted, producing a hormone called irisin that boosts body heat and creates brown fat cells (which get their color from their high iron content) out of white ones.

The study, published this week in the journal Cell Metabolism, is the latest look at brown fat and its benefits. Until just a few years ago, it was thought that humans lose their brown fat in early infancy. Since alandmark 2009 study in the New England Journal of Medicine, however, we’ve known that many—perhaps all—adults have stores of it, though in varying amounts.

To get a better grip on the science of shivering, we talked with the study’s lead author: Dr. Francesco Celi, chair of the Division of Endocrinology and Metabolism at the Virginia Commonwealth University School of Medicine and a former staff clinician at the National Institute of Diabetes and Digestive and Kidney Diseases.

In 2012 there was some important research on brown fat in rodents. How did that study lead to this one?

Two years ago a group of scientists were studying exercise in mice, and they made the seminal discovery that skeletal muscle produces a hormone called irisin, which can stimulate the activity and mass of brown fat.

But we were puzzled: It doesn’t make much sense that something that produces heat, like skeletal muscle, would generate a hormone that drives the increase in energy expenditure from another [thing like] brown fat.

So we thought outside the box and considered another form of muscle activity: shivering. Shivering is prompted by cold—it’s [an ancient biological] survival mechanism [that helps us] maintain our core temperature. That’s vitally important in preventing hypothermia.

So we realized that shivering, rather than exercise, could be the primary driver of irisin secretion. And we set up a series of clinical experiments to demonstrate that.

Some adults have more brown fat—and lower glucose—than others. Why is that?

That’s a great question. First of all, we still don’t know if every adult has brown fat. We just know that leaner individuals tend to have a greater amount of it [than heavier people]. But we don’t know if [it’s genetic or for some other reason].

Nor do we know what the effects are of chronically stimulating brown fat in adults. And that’s critical. We need to learn what all the metabolic consequences are of brown-fat activation.

[Our assumption], though, is that it would lead to an improvement of metabolism—and possibly to weight loss or maintaining weight loss.

Shivering is just one of our responses to cold, right?

[Humans have] three mechanisms to defend against cold. One is called vasoconstriction: Blood flow to the skin decreases, which increases the body’s ability to maintain temperature in the core [and protect vital organs].

The second one is called nonshivering thermogenesis. It’s probably related to brown fat, [and basically means] all of the chemical reactions that get activated during cold but don’t result in muscle contraction. Brown fat is the most efficient means of generating heat—an analogy would be a [super-efficient] furnace.

The third one is shivering, and it’s basically a last resort—unpleasant and highly inefficient. But it does contract the muscle fibers, which can produce enough heat to maintain your core temperature.

Irisin is at the center of this. What is it, exactly, and how does it work?

Irisin is [a hormone] produced by muscle contractions, either by exercise or shivering. Once it’s produced, it moves through the blood and turns white fat cells into brown ones.

Does this mean that exercise is, metabolically speaking, just another form of shivering? And that if I go and exercise in the cold, I’ll burn twice as many calories?

I doubt that there is an additive effect. Maximum exercise, as we measured during our experiments, did not produce any added amounts of irisin as compared to shivering. So I really doubt that exercising and shivering [at the same time] would do anything—aside from making you miserable—that would help you burn [twice as many] calories.

Do other species have this capacity?

Other species are not well studied. But we know that brown fat is present in hibernating mammals.

Going forward, what are the health implications of your findings?

[We have to see] whether it’s possible to use this discovery for weight loss, or to maintain weight loss. But it’s a promising pathway to look at, just from the substantial improvement of metabolism. [That could help with] diabetes [and obesity and a condition called fatty liver]. What we need to understand is whether there is any genetic difference in the response to this pathway.

[One thing we know is that] adaptive thermogenesis—the response to cold exposure—can be activated even by minimal changes in temperature. In our study we demonstrated that just by lowering the thermostat from 74°F (23°C) to 68°F (20°C) is sufficient to generate a measurable increase in energy expenditure.

That’s not [quite the same thing as] shivering. But it’s still measurable—and, potentially, clinically significant.

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Nanomotors are controlled, for the first time, inside living cells.


For the first time anywhere, a team of chemists and engineers at Penn State has placed tiny synthetic motors inside live human cells, propelled them with ultrasonic waves and steered them magnetically. It’s not exactly “Fantastic Voyage,” but it’s close. The nanomotors, which are rocket-shaped metal particles, move around inside the cells, spinning and battering against the cell membrane.

“As these nanomotors move around and bump into structures inside the cells, the live cells show internal mechanical responses that no one has seen before,” said Tom Mallouk, Evan Pugh Professor of Materials Chemistry and Physics. “This research is a vivid demonstration that it may be possible to use synthetic nanomotors to study cell biology in new ways. We might be able to use nanomotors to treat cancer and other diseases by mechanically manipulating cells from the inside. Nanomotors could perform intracellular surgery and deliver drugs noninvasively to living tissues.”

Up until now, Mallouk said, nanomotors have been studied only “in vitro” in a laboratory apparatus, not in living human cells. Chemically powered nanomotors were first developed 10 years ago at Penn State by a team that included chemist Ayusman Sen and physicist Vincent Crespi, in addition to Mallouk.

“Our first-generation motors required toxic fuels and they would not move in biological fluid, so we couldn’t study them in human cells,” Mallouk said. “That limitation was a serious problem.” When Mallouk and French physicist Mauricio Hoyos discovered that nanomotors could be powered by ultrasonic waves, the door was open to studying the motors in living systems.

For their experiments, the researchers use HeLa cells, an immortal line of human cervical cancer cells that typically is used in research studies. These cells ingest the nanomotors, which then move around within the cell tissue, powered by ultrasonic waves. At low ultrasonic power, Mallouk explained, the nanomotors have little effect on the cells. But when the power is increased, the nanomotors spring into action, moving around and bumping into organelles — structures within a cell that perform specific functions. The nanomotors can act as egg beaters to homogenize the cell’s contents, or they can act as battering rams to puncture the cell membrane.

While ultrasound pulses control whether the nanomotors spin around or whether they move forward, the researchers can control the motors even further by steering them, using magnetic forces. Mallouk and his colleagues also found that the nanomotors can move autonomously — independently of one another — an ability that is important for future applications.

“Autonomous motion might help nanomotors selectively destroy the cells that engulf them,” Mallouk said. “If you want these motors to seek out and destroy cancer cells, for example, it’s better to have them move independently. You don’t want a whole mass of them going in one direction.”

The ability of nanomotors to affect living cells holds promise for medicine, Mallouk noted.

“One dream application of ours is Fantastic Voyage-style medicine, where nanomotors would cruise around inside the body, communicating with each other and performing various kinds of diagnoses and therapy. There are lots of applications for controlling particles on this small scale, and understanding how it works is what’s driving us.”

Discover the power of alpha lipoic acid for removing heavy metals, taming diabetes and protecting against Alzheimer’s


With diabetes, cardiovascular disease and neurological disorders reaching epidemic proportions, natural remedies that combat these health concerns are in high demand. Alpha lipoic acid (ALA) can help with these pressing issues and more. This formidable antioxidant has also shown promise in curbing osteoporosis, reducing the damage caused by stroke, as well as preventing and treating Alzheimer’s disease.

A broad-spectrum wonder

In “Nutraceutical Update: Lipoic Acid,” Mark A. Mitchell, M.D., lists the following benefits of ALA:

  • Reduces oxidative stress in the body via powerful antioxidant activity
  • Improves several components of the metabolic syndrome – a combination of risk factors that increases one’s risk for diabetes
  • Reduces blood pressure
  • Reduces insulin resistance
  • Improves the lipid profile
  • Reduces weight
  • Increases insulin sensitivity
  • Improves diabetic neuropathy
  • Protects against cataract formation
  • Improves visual function in glaucoma
  • Helps prevents retinal cell death when combined with vitamin E in retinitis pigmentosa
  • Reduces brain damage after a stroke
  • Prevents bone loss, possibly through an anti-inflammatory effect
  • Reduces frequency and intensity of migraines
  • Improves skin texture

And this study found that supplementing with ALA can help reduce inflammatory reactions associated with multiple sclerosis. Additionally, lipoic acid helps to safeguard against heavy metal toxicity. Chelating arsenic, cadmium, lead and mercury, ALA renders the metals inactive and safely expels them from the body. An animal study in Toxicology also found that ALA shielded the liver against arsenic exposure. [1] Likewise, research has verified the protective properties of lipoic acid against mercury poisoning. [2]

Please note: before attempting a heavy metal detox with ALA or any other substance, it’s important to consult with a qualified practitioner to avoid potential side effects.

Dosage and use

The most potent form of lipoic acid is R-dihydrolipoic acid. The recommended dosage ranges from 300 to 1,800 mg per day. Taken with a B-complex vitamin, the bioavailability of ALA is given a significant boost.

Dr. Mitchell concludes, “[l]ipoic acid offers broad-spectrum protection against some of society’s troublesome health conditions, ranging from painful neuropathy and migraine headaches to disabling cataracts and neurodegenerative conditions. You can begin optimizing your body’s levels of protective antioxidants today using supplements of lipoic acid or its high-potency cousin, R-dihydrolipoic acid.”

Are You Game?


  • Practicing for citizen science games?
So… and be honest now… have you gotten sucked into one of these games like Candy Crush, or Farmville, or Mafia Wars?And have you ever felt maybe a little bit guilty about it afterward? Wished they weren’t quite so mindless and yet so darned addictive?Not to worry. Not only are you not alone in this regard—estimates for 2013 suggested there would be 80.3 million social network users playing games at least once per month and another 125.9 million mobile phone gamers—but there’s a way to put your video game habit to work for a good cause: citizen science.The latest game to come out is called “Play to Cure: Genes in Space.” Your mission, should you choose to accept it, is to collect a substance called “Element Alpha,” where the Alpha is actually genetic cancer data.Unlike other citizen science games, which play like puzzles, this one plays a bit like a strategy game and a bit like a first person shooter. You first map your path through the Element Alpha field that you’re assigned by drawing lines through the densest areas, and then you actually fly through it with your space ship, blasting your way through asteroids. As you progress, you can upgrade your ship to level up, which allows you to pick up more Alpha, and on it goes.What you’re really doing, of course, is helping researchers analyze large amounts of genetic data quickly. The information will then be used to develop new treatments for cancer.

NIH study finds regular aspirin use may reduce ovarian cancer risk.


Women who take aspirin daily may reduce their risk of ovarian cancer by 20 percent, according to a study by scientists at the National Cancer Institute (NCI), part of the National Institutes of Health. However, further research is needed before clinical recommendations can be made. The study was published Feb. 6, 2014, in the Journal of the National Cancer Institute.

It is estimated that over 20,000 women in the United States will be diagnosed with ovarian cancer in 2014, and more than 14,000 will die from the disease. Early stage ovarian cancer may be successfully treated. However, symptoms associated with this disease can mimic more common conditions, such as digestive and bladder disorders, so for this reason and others, it is often not diagnosed until it has reached advanced stages. Late stage ovarian cancer leaves women with limited treatment options and poor prognoses, making preventive strategies potentially important for controlling this disease.

Chronic or persistent inflammation has been shown to increase the risk of cancer and other diseases. Previous studies have suggested that the anti-inflammatory properties of aspirin and non-aspirin NSAIDs (non-steroidal anti-inflammatory drugs), may reduce cancer risk overall. However, studies examining whether use of these agents may influence ovarian cancer risk have been largely inconclusive. This is the largest study to date to assess the relationship between these drugs and ovarian cancer risk.

Britton Trabert, Ph.D., and Nicolas Wentzensen, M.D., Ph.D., of NCI’s Division of Cancer Epidemiology and Genetics, and their colleagues, analyzed data pooled from 12 large epidemiological studies to investigate whether women who used aspirin, non-aspirin NSAIDs, or acetaminophen have a lower risk of ovarian cancer. These 12 studies (nine from the United States) were part of the Ovarian Cancer Association Consortium. The scientists evaluated the benefit of these drugs in nearly 8,000 women with ovarian cancer and close to 12,000 women who did not have the disease.

Among study participants who reported whether or not they used aspirin regularly: 18 percent used aspirin, 24 percent used non-aspirin NSAIDs, and 16 percent used acetaminophen. The researchers determined that participants who reported daily aspirin use had a 20 percent lower risk of ovarian cancer than those who used aspirin less than once per week. For non-aspirin NSAIDs, which include a wide variety of drugs, the picture was less clear: the scientists observed a 10 percent lower ovarian cancer risk among women who used NSAIDs at least once per week compared with those who used NSAIDs less frequently. However, this finding did not fall in a range that was significant statistically. In contrast to the findings for aspirin and NSAIDs, use of acetaminophen, which is not an anti-inflammatory agent, was not associated with reduced ovarian cancer risk.

This study adds to a growing list of malignancies, such as colorectal and other cancers, that appear to be potentially preventable by aspirin usage. “Our study suggests that aspirin regimens, proven to protect against heart attack, may reduce the risk of ovarian cancer as well. However intriguing our results are, they should not influence current clinical practice. Additional studies are needed to explore the delicate balance of risk-benefit for this potential chemopreventive agent, as well as studies to identify the mechanism by which aspirin may reduce ovarian cancer risk,” said Trabert.

Adverse side effects of daily aspirin use include upper gastrointestinal bleeding and hemorrhagic stroke. Therefore, a daily aspirin regimen should only be undertaken with a doctor’s approval, caution the scientists.

Nasa takes one giant leap towards mining minerals from the moon.


 

US space agency has started accepting proposals from private companies to help design and build lunar prospecting robots

In a giant leap that seems to have come straight from the world of science fiction, Nasa today began accepting applications from private companies who want to launch mining operations on the moon.

As part of a scheme that was unveiled in late January, the US space agency is inviting offers from potential business partners to help design and build lunar prospecting robots, the first major step required to explore Earth’s natural satellite for valuable resources.

Nasa has been forced to set up the Lunar Cargo Transportation and Landing by Soft Touchdown programme (Catalyst) on a skeleton budget, because the US government has refused to provide any funding.

That sets it apart from the agency’s deals with other private companies to deliver supplies to the International Space Station – which are backed by public coffers.

If you have a novel idea on the best way to scour the moon for minerals, and a few billion pounds going spare, Nasa is accepting proposals from today until 17 March, 2014, according to reports fromThe Verge.

Jason Crusan, director of Nasa’s advanced exploration systems, told the AFP news agency mining the moon was far from just the stuff of fantasy.

He said recent missions had already revealed evidence of water and other substances of interest on the moon’s surface. “But to understand the extent and accessibility of these resources, we need to reach the surface and explore up close,” he said.

“Commercial lunar landing capabilities could help prospect for and utilize these resources,“ he added, which could allow for both commercial and research activities.

“As Nasa pursues an ambitious plan for humans to explore an asteroid and Mars, US industry will create opportunities for Nasa to advance new technologies on the moon,” said Greg Williams, a top Nasa official.

Scientists still face a rocky road ahead before they can realise the dream of mining in space, however. A Harvard research paper published just last month suggested that the vast majority of near-Earth asteroids would be unsuitable for mining on a commercial scale.

And the question of who actually owns the moon – and therefore the profits from mining it – remains unresolved. With China and the US already in conflict over the former’s attempts to land a rover on the moon, we could yet see the world involved in a lunar land-grab in years to come.

The killing of Marius the giraffe opens an important debate about genetics, animal rights and zoo inbreeding


  

As staff at Copenhagen Zoo receive death threats after the culling of an 18-month-old giraffe for ‘conservation reasons’, Cahal Milmo reports on how the animal’s death has divided geneticists and animal rights activists worldwide

Marius was ill-fated but he was not the first. There were the two leopard cubs culled at Copenhagen Zoo in 2012. Four years before that, three Siberian tigers were put to sleep in Germany. Like the giraffe, all were healthy. But their genes did not fit with the fight to conserve their species, with experts worrying they were too similar – or not similar enough – to others in breeding programmes to allow them to mate.

While the reasoning might be familiar to geneticists, the sight of 18-month-old Marius being dissected in front of visitorsto the Danish capital’s zoo over the weekend, after it had been dispatched with the aid of a piece of bread and a bolt gun, sparked anger and incomprehension worldwide. Pictures of the dismembered corpse then being fed to lions reinforced the impression, for some, that the law of the savannah had been perversely transplanted to the civilised climes of urban Scandinavia.

The brutal destiny of Marius has also brought into sharp relief much wider questions about what purpose is served by zoos and whether their mission to conserve and educate is being compromised by profit and space.

Few zoos advertise when they put down healthy creatures which, broadly, they have pledged to help save from the spectre of extinction.

Zoo managers in Copenhagen confirmed the perils of the practice last night by revealing that staff, including its head of conservation, had received death threats by phone and email since a petition and an offer by the Yorkshire Wildlife Park to take in Marius failed to save him.

Zoo managers insist the culls are scientifically justified. Copenhagen Zoo said Marius, and the two-year-old leopards in 2012, were killed because the animal’s genes were already well-represented in captive populations. In the German case, it had been discovered the cubs’ father was not a 100 per cent pure Siberian tiger.

But animal rights groups on Monday claimed that the culling of healthy “surplus animals” was being repeated regularly in Europe’s leading zoos and kept out of public view to avoid the difficult debate. Campaigners said there are about 7,000 animals in zoos in Europe which could be considered surplus to need and accused some institutions of breeding “box office” species to draw crowds when the animals are young before culling them in adulthood.

The European Association of Zoos and Aquaria (Eaza), the body which approved the decision to euthanise Marius, insisted incidents remained rare. Since records began around a century ago, five giraffes have been put down for similar “conservation management reasons” out of a captive population in Europe that now stands at 798.

Figures for other species are hard to come by. Eaza, along with the British and Irish Association of Zoos and Aquaria, said they were unable to provide an exact figure for animals culled.

The Zoological Society of London, which runs London Zoo, said it worked hard to avoid euthanasia but had to use the procedure for welfare reasons with some fast-breeding species that cannot be managed with contraception. Last year, it put down eight Australian water rats, eight brown rats and 61 Seba’s bats out of a group of 200 to reduce “health and aggression issues”.

For zoos, the need to reach for the bolt gun or the lethal injection is a last resort in a much larger battle to build captive populations of animals – from black rhinos to Amazonian frogs – which are endangered or on the brink of extinction. David Williams-Mitchell, of Eaza, said: “There are habitats which are disappearing and zoos are the last line of resistance in building captive populations…

“But in order for the captive populations to be viable, in-breeding must be avoided. Breeding without attention could allow genes which increase the likelihood of major problems in the future to be passed… throughout captive populations.”

Zoos across Europe act as a coalition in the European Endangered Species Programme (EEP), pooling resources to build genetically-diverse species for potential release into the wild.

Attitudes to euthanasia are different in the US, where zookeepers put hormones in the feed of giraffes and giving chimpanzees human birth control pills.

Some European zookeepers argue that it is better from a welfare perspective to allow adult animals to procreate and raise young, and then euthanise unwanted offspring at the point when they separate from their parents. As such, they are only recreating what would occur in the wild.

But Mark Jones, a vet and executive director of the British office of the Humane Society International, said: “The fact of the matter is that it is the young animals that help zoos to draw in the crowds and zoos are finding that when they reach maturity there is no space for them and no market for them in other zoos.”

Eaza yesterday reaffirmed its backing of Copenhagen Zoo, saying it was putting in the public domain a debate that should not be “just swept under the carpet”.

Others differ. Liz Tyson, of the British-based Captive Animals Protection Society, said: “Marius was never destined to be released to the wild. He was bred to spend his life in unnatural, man-made surroundings because zoos make money from showing off exotic animals.

“If we… want to prevent further needless deaths, the answer is simple – do not visit the zoo.”

Afghanistan polio: Girl diagnosed with first case in Kabul since 2001.


A three-year-old girl was diagnosed with the infectious disease in the capital

Afghan officials have launched a polio vaccination campaign after the first case of the disease was diagnosed in the capital since the fall of the Taliban in 2001. 

A three-year-old girl from the eastern part of Kabul was diagnosed with the disease, according to Dr. Kaneshka Baktash, spokesman for the Afghan Public Health Ministry.

She has been left partially paralysed and has now been taken to Pakistan by her family for treatment.

Mr Baktash said that his ministry has launched a vaccination campaign across the capital and in the area where the girl was living.

Polio has almost been wiped out across the world, and Afghanistan, Pakistan and Nigeria are the only countries in the world where polio remains endemic, although cases of the disease have declined significantly.

Smoking in cars with children present will be made illegal before 2015 elections.


 Smoking in cars when children are passengers will be outlawed in England by the next general election in May 2015, Downing Street pledged today.
Its promise came after the ban was overwhelmingly supported by MPs of all parties in a free vote in the Commons.

The Department of Health is now drawing up plans to turn the vote into legislation. The Prime Minister’s official spokesman said the Government’s intention was for the ban to “be in force ahead of 2015”.

The move was approved by 376 to 107, a majority of 269, in a free vote which had divided the Cabinet.

It gave authority for Jeremy Hunt, the Health Secretary, to introduce a ban in England and for the Welsh Government to take the same step.

The vote passed despite the opposition of several senior ministers including Theresa May, the Home Secretary, Iain Duncan Smith, the Work and Pensions Secretary, and Chris Grayling, the Justice Secretary.

The outcome pleased health campaigners who said it would help to protect hundreds of thousands of children from the effects of exposure to second-hand smoke.

But critics complained that the planned law would be difficult to enforce and would represent an unreasonable incursion by the state into private lives.

Women with cystic fibrosis exhibit higher insulin secretion than men.


In patients with cystic fibrosis, adult women demonstrate higher insulin secretion than their male counterparts, suggesting a potential sex dimorphism in this disease, recent study data found.

Moreover, women with cystic fibrosis had insulin secretion levels comparable to those of healthy women, whereas men with cystic fibrosis had significantly lower insulin levels than healthy men.

To investigate the role of sex on insulin homeostasis and cystic fibrosis-related diabetes (CFRD), the researchers recruited 230 patients (123 men, 107 women) with cystic fibrosis from the Montreal Cystic Fibrosis Cohort. All patients were of comparable age and had normal lung function.

In addition, 44 healthy controls (25 men, 19 women), matched for age and BMI, were recruited from the Institut de Recherches Cliniques de Montréal.

All study participants underwent a 2-hour oral glucose tolerance test after an overnight fast. In less than 5 minutes, they drank 1.75 g glucose/kg of body weight, with a maximum of 75 g, based on guidelines from the Canadian Diabetes Association. The researchers then obtained blood samples at 0, 30, 60, 90 and 120 minutes to assess plasma glucose and insulin levels.

The researchers found that the overall insulin secretion of female participants with cystic fibrosis was higher than those of men with cystic fibrosis (P<.05) and similar to the insulin secretion of healthy women (P=.606). Conversely, men with cystic fibrosis had lower overall insulin concentrations than healthy men (P=.02) and higher insulin sensitivity (P=.009) than female patients with cystic fibrosis. The overall glucose fluctuations of patients with cystic fibrosis were higher than in healthy patients.

The gender-based differences remained consisted in the patients with cystic fibrosis after follow-up.

The researchers said these findings ran counter to their hypothesis, and their full implications are not yet clear.

“Contrary to our hypothesis, adult women with [cystic fibrosis] are characterized by higher insulin secretion than men with [cystic fibrosis],” the researchers wrote. “This data should be confirmed in other [cystic fibrosis] populations and the potential implications of this sex difference (eg, CFRD risk, lung function and/or weight maintenance) remain to be established.”

source: Endocrine Today