Fact or Fiction: Does Coca Candy Prevent Altitude Sickness?

Trekker resting in height mountain

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This summer, I spent a month studying at the Universidad de los Andes in Chile. We visited the Atacama Desert, the driest non-polar desert in the world. It is nestled between two sets of mountains; during one of our excursions we hiked up the Andes Mountains to a village called Socaire, located at an altitude of around 11,000 feet above sea level.

Our site coordinator, physiology professor and “temporary mom,” Anne Crecelius, PhD, kindly offered us coca candy, hoping it might prevent the dizziness, nausea and headaches sometimes associated with altitude sickness. She had asked us to drink more water than we usually do, too, just in case anyone in our group responded badly to being so high up. Coca candy is made in part from coca leaves, a plant that local people have chewed on for thousands of years. Coca leaves contain chemical compounds called alkaloids, which have been shown to reduce hunger and calm the side effects of high-altitude travel.

The question remains whether coca really has physiological benefits. The research is mixed. Some studies, citing the uses of coca throughout history, claim that there are significant benefits to chewing coca leaves. They recount improved energy efficiency during exercise, boosted energy levels—similar to the effect of caffeine in coffee—and decreased thirst and appetite.

However, other researchers suggest that the effects of coca leaves are mostly psychological, similar to a placebo effect (using a fake treatment, or placebo, in a group of people to compare the effects with people using a real treatment). In some cases, the group taking the placebo will also see improvement in their condition.

Even if coca leaves do prevent altitude sickness symptoms, the candies we munched on did not contain enough coca to help much. But perhaps they were enough to create some sort of placebo effect in our group, as no one was sick, just a little out of breath. Nevertheless, we enjoyed the town, the candy and a snowball fight near a very old church. Who knew that a small town at high altitude could be so much fun? Most likely, the locals and generations of indigenous people, who also know of the power of coca.

Andrew KramerAndrew Kramer is an exercise physiology major at the University of Dayton. Anne R. Crecelius, PhD, is an assistant professor in the Health and Sport Science Department at the University of Dayton. They spent four weeks in Chile as part of a study abroad program in partnership with the Universidad de los Andes, studying nutrition, sports and research in the context of the Chilean culture. This is the second in a three-part series that spies physiology in this dynamic South American country. Read part one.

 

Being Left (Handed) Is All Right

Little boy writing on green blackboard

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“There’s something I ought to tell you. I’m not left-handed either.” – Westley, The Princess Bride

Throughout history, left-handedness has both fascinated and frightened people. Maybe it is because only about 15 percent of the population is left-handed. Or maybe it is because the reasons for left-handedness remain somewhat of a mystery.

What makes a person left- or right-handed? It seems we can find the answer in our genes, at least partially. Most researchers in the field agree that left- or right-handedness is most likely produced by genetic influences. We inherit our genes from our parents, and the genes that are turned on determine our characteristics. The specific reasons behind these genetic differences are still hotly debated, but many studies seem to point to natural selection as a probable cause.

The human brain is divided into the right and left hemispheres, with nerve fibers connecting the two. Different parts of each half of the brain control different functions of the body. Many evolutionary biologists argue that evolution produced a majority of people who controlled language with their left brain, which also controls the right side of the body, including the right hand. As written language developed, people with genes toward right-handedness had a genetic advantage and passed those genes down to their children. But the question remains: Why are some people left-handed when natural selection seems to be evolutionarily “against” left-handedness?

Scientists have discovered that handedness is influenced by not just one, but a group of genes, and that these genes can be influenced by external and societal pressures. For example, if a person expresses the genes for left-handedness, they may be taught to write with their right hand. In the same way, a person who writes with their right hand can be taught to use their left hand to throw or shoot a ball for a competitive advantage.

Although it may be more difficult to find a pair of scissors or spiral notebook that are easy to use, left-handedness has its advantages. Left-handers have been shown to have greater coordination, and left-handedness has been linked to creativity, especially in men. This may be due to the connection with the right brain, which is the creative hemisphere. Many lefties excel in sports such as tennis and fencing, possibly because there are fewer left-handed opponents.

While research continues into what makes left-handed people unique, we can celebrate our left-handed friends now in honor of Lefthanders Day on August 13.

Audrey Vasauskas

Beer Does a Body Good?

Drinks: Beer Isolated on White Background

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Bone is a living organ that constantly breaks down and rebuilds itself. As we get older, bone breaks down more and rebuilds less, which often leads to weaker bones over time. If we lose too much bone, we increase our risk of fracture and developing osteoporosis.

Women tend to have weaker bones and a faster rate of bone loss—particularly after menopause—than men. Approximately 50 percent of women in the U.S. over the age of 50 will break a bone due to osteoporosis. If the broken bone is in the hip, there is about a 20 percent chance that the individual will die within one year. Breaking a bone in our later years can significantly affect quality of life and the ability to live independently. Therefore, it is important to do everything we can to minimize age-related bone loss.

Lifestyle choices can help minimize bone loss, including:

  • following a healthy diet with enough calcium and vitamin D;
  • participating in regular physical activity; and
  • refraining from smoking.

Believe it or not, drinking a beer now and then may even help.

Researchers in Spain have discovered a link between beer consumption and bone health in women. They found that women who drank moderate amounts of beer—defined in the U.S. as up to one 12-ounce beer per day—had stronger bones than those who did not.

Beer contains two important nutrients that could be beneficial to bone health: phytoestrogens and silicon. Phytoestrogens are naturally occurring nutrients in plants that act similar to the hormone estrogen. Estrogen protects women from bone loss, but levels drop significantly after menopause. Estrogen deficiency is the primary cause of bone loss after menopause. Silicon is a naturally occurring mineral that may be used as a supplement to reduce bone breakdown and increase bone rebuilding in women with osteoporosis. Beer is one of the most plentiful sources of silicon in the Western diet.

It’s likely that the combination of phytoestrogen and silicon in beer helps limit bone loss. This finding has potentially important implications for bone health, although more study is needed.

It is also important to remember that drinking too much alcohol has many negative health effects, including reduced bone strength. Keep beer intake at a moderate level. That said Aug. 4 is International Beer Day. Drink a toast to healthy bones!

 

Kim HenigeKim Henige, EdD, CSCS, ACSM EP-C, is an associate professor and undergraduate program coordinator in the department of kinesiology at California State University, Northridge.

 

Spinal Cord Injury: Let’s Clear the Air(ways)

Human Spine Anatomy

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The spinal cord is the information processing highway in animals (including humans) that have a backbone. In humans, the spinal cord contains nerve cells called motor neurons that control movement in the muscle fibers of the body, similar to the way a puppeteer controls the movements of a puppet.

About 17,000 people in the U.S. sustain new spinal cord injuries (SCI) each year, and roughly 300,000 people in the U.S. live with an SCI. Motor neuron damage in the spinal cord may lead to a variety of problems, including:

  • decreased mobility and independence;
  • loss of independent breathing;
  • injuries associated with using a wheelchair, such as pinched nerves and muscle strain;
  • partial or total inability to control the bowels and/or bladder; and
  • sexual dysfunction.

New research is addressing all of these important problems, but one area that is not as widely studied is airway clearance. Most of the time we can clear our airways ourselves through coughing and sneezing, but these actions become more difficult with SCI. Close to half of all people with SCI have damaged the motor neurons that control their diaphragm, the muscle that sits below the lungs and helps us breathe. As a result, people with SCI have an increased risk of potentially fatal airway infections such as pneumonia.

Fortunately, about 90 percent of these injuries are incomplete, meaning that some of the neurons still function. People with incomplete SCI have some sensation below the injury site and can often breathe on their own. We only need 10 to 20 percent of our diaphragm muscle to activate in order to breathe, but almost the entire muscle needs to be functional to cough and sneeze. When the motor neurons controlling the diaphragm are injured, the organ isn’t able to generate the forces necessary to clear the airways fully.

Over time, the neurons in the diaphragm that still function in an incomplete SCI may adapt to take over other jobs besides just breathing. This is called neuroplasticity. Neuroplasticity in the spinal cord is a valuable topic of research.  Researchers are looking for new ways to manipulate this process to help people with SCI learn new airway clearing methods which would likely reduce their health risks and improve their quality of life.

 

obaid-khurram-15978141Obaid Khurram is a PhD candidate in the biomedical engineering and physiology program at Mayo Clinic Graduate School of Biomedical Sciences. His research focuses on the neuromotor control of the diaphragm muscle, particularly after motor neuron loss or muscle weakness.

 

What Animals Can Teach Humans about Muscle Maintenance

Hiding Groundhog

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We all know the saying “use it or lose it.” Your muscles and nerves are no exception. When people are not active, whether it’s because of bed rest, spinal cord and nerve injury, or other reasons, two big problems arise. First, the muscles shrink by losing protein (a state called atrophy). Second, nerve cells have trouble firing electrical signals to communicate with the muscles. This combination can make it harder for people who are inactive to perform normal activities in their daily lives.

Unlike in humans, inactivity in other animals is not always such a bad thing. Certain animals in the wild need to stay inactive (dormant) to survive in their environment. During times of low food availability and harsh environmental conditions, ground squirrels, frogs, bats, turtles and bears may remain inactive. In the winter, this is called hibernation, and in the summer, it’s known as estivation. Quite often, these animals’ muscles are less active than normal or completely inactive for several months at a time. Some frogs can even survive under water during the winter without using their breathing muscles. Based on the idea of  “use it or lose it,” you might think that hibernating animals wouldn’t be able to run, jump, fly or even breathe normally after months of not using their muscles. Think again!

Understanding how animals immediately return to using their muscles and nerves normally after long stretches of dormancy is a major area of research. By learning how different animals dodge neuromuscular problems related to inactivity, scientists can figure out why human muscles and nerves are not as well-equipped. For example, hibernating animals activate genes that reduce the loss of muscle protein and use less energy during periods of inactivity to avoid atrophy. These discoveries have the potential to provide new treatment options for people who are confined to bed rest or who suffer nerve injuries that leave muscles unable to contract.

Animals have already solved many problems that plague humans, such as nerve and muscle inactivity. Research that compares animal and human function is an example of comparative physiology. Comparative physiology findings can help scientists make important discoveries that would not be possible if the cures hiding inside animals were overlooked.

Joe SantinJoe Santin, PhD, is a postdoctoral fellow at the University of Missouri-Columbia.

 

Can Exercising in Low-Oxygen Conditions Help Breast Cancer Survivors?

Supporting each other in the race against breast cancer

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Physical activity has been linked to a lower risk of developing several types of cancer, including breast cancer. Walking a few hours a week may even decrease the risk of a breast cancer recurrence as well as dying from the disease. The American Cancer Society currently recommends that people recovering from cancer should exercise at least 150 minutes per week.

But people with breast cancer often face a number of challenges to establishing a regular exercise program. Chemotherapy and radiation can affect heart and lung function, and about 60 percent of breast cancer survivors have reduced strength in their legs as a result of a loss of muscle mass. In addition, more than 80 percent of women gain weight after a diagnosis of breast cancer. These factors, along with fatigue from treatment, can prevent breast cancer survivors from being as active as they want to be.

Knowing that exercise is beneficial for people with breast cancer but that they face challenges, researchers at the University of Alabama at Birmingham (UAB) are looking at new ways to improve breast cancer survivors’ response to exercise. Their study compares the effects of exercising under low-oxygen conditions—similar to that seen at an altitude of 7,000 feet—with exercising in normal oxygen conditions at sea level.

Elite athletes sometimes train in mountainous areas—between 5,000 and 8,000 feet above sea level—to improve their performance. The air at high altitudes is thinner and contains less oxygen. Lower oxygen levels help boost the number of red blood cells that carry oxygen around your body. Exercising at high altitudes also lets you train harder without the added stress on your joints and muscles that occur at sea level.

While it is impractical to take cancer survivors to the mountains, UAB researchers are trying to bring the mountains to the patients During exercise sessions, participants wear a mask that is connected to a machine that controls the amount of oxygen they breathe in. This mimics the low-oxygen levels of a high-altitude workout.

The study is ongoing, so it is too soon to know how beneficial exercising under lower oxygen levels will be. However, the researchers predict that exercising in low-oxygen conditions will trigger a number of physiological changes that will let people with breast cancer be more active and improve their overall health. If the results of the study are correct, it may lead to new approaches to help breast cancer survivors lead a more active life.

 
John Chatham

John Chatham, DPhil, is a professor of pathology and director of the Division of Molecular and Cellular Pathology at the University of Alabama at Birmingham.

Not Horsing Around: Therapeutic Effects of Horseback Riding

Anne with students and Paralympians

Anne R. Crecelius, PhD, and students visit with La Roja Paralimpica athletes in Chile.

Choosing your favorite part of a trip can be a difficult decision for travelers. I had countless unforgettable and unique experiences during a recent four-week trip to Chile. One excursion that stands above the rest was a weekend trip to San Pedro de Atacama in Northern Chile.

I was studying with a group of students who had booked a horseback riding tour through the oasis of Sequitor. With the Andes Mountains as our backdrop, we spent two hours enjoying the perfect blue sky, warm sun and crisp air. This small agricultural region is in what is often called the driest desert in the world.

I had never been horseback riding and did not realize how much coordination, strength

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Molly Gearin tries her hand at horseback riding.

and physical and mental stamina it required. I later learned that horseback riding is a type of rehabilitative treatment—called hippotherapy—that may improve coordination, balance and strength in people with physical disabilities, including cerebral palsy (CP).

CP is a neurological disorder that affects body movement and coordination. Studies have shown that hippotherapy can improve joint stability, balance and painful muscle contractions in people with CP. Children with CP may especially benefit from hippotherapy. Therapeutic riding can change how the abdominal and lower back (core) muscles respond to different movements. These physiological benefits can improve posture and the overall quality of life in some children, particularly among those who have the ability to walk, run and jump.

Researching hippotherapy was not the first time I thought about people with CP on our trip to Chile. Another favorite activity was our opportunity to watch La Roja Paralimpica, the Chilean Paralympic Fútbol 7-a-side team, practice. This sport is adapted from traditional fútbol (soccer) to accommodate athletes with disabilities. The modified rules allow Paralympic athletes to enjoy a sport that is at the heart of Chilean culture.

As a future physical therapist, I enjoyed observing elite athletes at work and learning about hippotherapy, an activity that could be of benefit to people with CP.

– Molly Gearin (Anne Crecelius contributed to this post)

Molly Gearin is a pre-physical therapy major at the University of Dayton. Anne R. Crecelius, PhD, is an assistant professor in the Health and Sport Science Department at the University of Dayton. They spent four weeks in Chile as part of a study abroad program in partnership with the Universidad de los Andes studying nutrition, sports and research in the context of the Chilean culture. This is the first in a three-part series that spies physiology in this dynamic South American country.

 

 

The Brain in Your Gut

Relation of human brain and guts, second brain

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Did you know your gut has a brain of its own? It’s called the enteric nervous system. The brain in your gut is embedded in the wall of the digestive tract. Together with your “big brain,” the enteric nervous system helps control gastrointestinal function, including the mixing and grinding of food in the stomach and absorption of nutrients in the intestines.

An adult’s enteric nervous system is made up of 200 to 600 million nerve cells (neurons). That’s as many neurons as are in a cat’s brain or even your spinal cord! The neurons in the enteric nervous system interact with smooth muscle to move food through the digestive system. The brain in your gut also plays an important role in regulating your immune system. It attacks bacteria and viruses (pathogens) that invade the digestive tract by releasing protective substances called peptides that make it harder for pathogens to do harm.

Although the brain in your gut functions independently from the “big brain”—and is the only organ in your body that can do so—normal digestive function requires communication between the enteric nervous system and the brain. The enteric nervous system provides sensory information to the brain to help you decide what, when and how much you eat. When you’re hungry or see something you’re craving (like a piece of chocolate cake or a juicy burger), your brain tells your gut to start the digestion process by producing gastric secretions in the stomach.

Problems with the enteric nervous system can lead to different digestive diseases such as irritable bowel syndrome and functional constipation. Studies have demonstrated that losing some of the neurons in the gut can be a cause of these conditions. Understanding how and why these neurons die is an important topic of research that could result in finding new treatments for digestive diseases.

To learn more about digestive disease, visit the National Institute of Diabetes and Digestive and Kidney Diseases website.

 

Ninotchska DelvalleNinotchska Delvalle is a doctoral candidate in the neuroscience program at Michigan State University. Her research focuses on how specialized cells of the enteric nervous system (enteric glia) contribute to the development of gastrointestinal disease.

Myasthenia Gravis May Be (Literally) All Greek to You

neuron

Myasthenia gravis is a disease that affects the way that muscles receive signals from nerves. Myasthenia is Greek for “muscle weakness,” which is a good description of this disease’s symptoms. Muscle weakness, which worsens after physical activity but gets better with rest, is the primary symptom of the condition.

Weakness may occur in any skeletal muscle, but smaller muscles in the face are commonly affected. This leads to symptoms that may include:

  • difficulty chewing or swallowing,
  • speech impairment,
  • altered facial expression,
  • drooping eyelids, and
  • blurred vision.

Weakness in the limbs is often a symptom when larger muscles are affected. One of the most serious consequences of myasthenia gravis is a myasthenic crisis, which occurs when the respiratory muscles that allow us to breathe are affected. Someone in myasthenic crisis may need a machine (ventilator) to help them breathe if they have trouble on their own.

An understanding of how nerves work with muscles is important to understanding the effects of myasthenia gravis. The brain sends signals through the nerves, telling them which direct body parts to move. The signals travel down nerves to nerve endings, which are located very close to—but not touching—muscle fibers. Nerves release chemicals called neurotransmitters to send signals that bridge the gap between the nerves and muscles. Neurotransmitters bind to molecules on the surface of the muscle cells (receptors) that send a signal inside the cell. Acetylcholine is a neurotransmitter that causes muscle movement when it binds to its receptor. The normal interaction between a neurotransmitter and receptor doesn’t always work as smoothly as it should. In some cases, the immune system interferes, producing proteins called antibodies that are meant to protect the body from substances that might harm it. In the case of myasthenia gravis, the immune system makes antibodies that bind to acetylcholine receptors, which prevents the interaction between the neurotransmitters and receptors.

The disease typically occurs in women under 40 and men over 60, but it can develop at any age. Myasthenia gravis may be debilitating, but the good news is that symptoms can usually be controlled with medication. Steroids can help limit the production of antibodies that target acetylcholine receptors. Drugs called acetylcholinesterase inhibitors increase muscle strength by slowing the breakdown of acetylcholine. When neurotransmitters remain for longer periods of time, signals to the muscles are more likely to go through.

As you enjoy the outdoors and weather during Myasthenia Gravis Awareness Month, keep in mind all the things your muscles and nerves are doing without you even thinking about it.

 

Rebekah Morrow 3Rebekah Morrow, PhD, is an assistant professor of immunology and microbiology at the Alabama College of Osteopathic Medicine.

Like Father, Like Son (and Daughter): How Your Dad’s Past Affects Your Future

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What makes your father the best dad in the world? Maybe it’s his sense of humor or the times he has taken you to the movies or played catch in the yard. Or maybe it’s the fact that he made healthy lifestyle choices before you were born. Recent research suggests that your father’s health before you were conceived (preconception) may change the way your genes behave to affect your future health. It almost sounds like something out of a science fiction movie, but it’s real.

Studies tend to focus on the mother’s preconception health and the risks her baby might face later in life if she’s overweight. But a dad’s weight and early eating habits can also play a role, according to research published in the American Journal of Stem Cells. Researchers found that offspring of men who were obese before reproducing were more likely to have diabetes and be overweight. On the other hand, the researchers also found that fathers who had limited food resources in their early life caused genetic changes that protected their children—and even grandchildren—against cardiovascular disease.

Most people know that exercise is one of the healthiest lifestyle choices you can make to maintain your weight and keep your heart and even your brain healthy. However, research presented at the APS Integrative Biology of Exercise 7 meeting showed that offspring of men who exercised long term before conceiving had a higher likelihood of being obese and developing diabetes. This result was a huge surprise to the research team, but is it a reason to stop exercising? Not really. The study focused on how efficiently the body used energy on a high-fat diet. Limiting dietary fat and being active is still the way to go for most people.

Keeping stress levels low is also a good plan for dads-to-be. One study suggests that a man’s preconception stress may program his kids for mood disorders. Researchers found a pathway in the brain that transmits signals about stress hormones, and it may be passed down to the next generation.  If the signal is passed on to you, then your father’s stress levels could affect your predisposition for anxiety and depression.

These studies represent clues to learning how genetic material is transformed as it passes through generations. It’s also a reminder that following a healthy diet, staying active and maintaining mental health is important for everyone at every age.

Happy Father’s Day!

– Erica Roth