The Effects of Sleep Deprivation on the Human Body

Since coronavirus has forced the U.S into a nationwide shutdown, many of us have found ourselves staying up well past the time we did before. Personally, it is a rarity for me to go to bed before 2 AM now, and it is the same for many of my friends and it probably is for you right now, as you sit here reading this. If it isn’t, I envy you.

Screenshots of my friends telling me to go to sleep/ questioning my sleep schedule

Even though the nation is shut down, which includes school, most of us still need to wake up at some point to do work or participate in class. To many, this is an issue because it means that we have to get up before 11 AM, meaning that many people are not getting the right amount of sleep. Unfortunately, this tiredness was probably even more prevalent in pre-corona life. As kids struggled to cram school, homework, sports, and more time-consuming extracurriculars into a short 24-hour span, they more often than not put aside one of the most important tasks: sleep. An important factor that makes it all the more impossible for teenagers to get enough sleep is how their circadian rhythms change when they reach puberty. This causes for teens to begin to release melatonin much later, causing teenagers to become tired around 10:00 or 11:00 instead of 8:00 or 9:00. According to the CDC, teenagers (ages 13-18) require 8-10 hours of sleep each night. During the school year, I know that that is almost impossible to reach. I found myself getting maybe 5-6 hours of sleep most nights, and many of my fellow peers were probably getting around the same amount. According to the CDC, 72.7% of high school students said that they did not get enough sleep. When a teenager begins to get tired at around 11:00, yet has to get up for school around 6:30, it is awfully difficult for a teenager to get at least 8 hours of sleep. Besides the rigorous schedules that some students may subject themselves to, the delay of melatonin release also prevents students from getting adequate rest.

Chronic sleep deprivation can wreak havoc on a person’s body. When you sleep, your pituitary gland releases hormones, primarily somatotropin (also known as GH), that cause your bones and muscles to grow, fat metabolism increases, and your immune system functions much better. When an individual suffers from chronic sleep deprivation, there is an increased risk of diabetes, heart arrhythmia, high blood pressure, cancer, obesity, and many more. All of these health issues sound scary and like the side effects that you would read off of a bottle for a new weight-loss drug. In regards to your immune system, the cells that destroy viral and cancerous cells do not function as well when you are sleep deprived. Reproduction of antibodies is also altered when one is chronically sleep deprived. 

Even more interestingly, sleep deprivation has a profound effect on the brain. I found this one really cool TedTalk about how a lack of sleep affects the hippocampus, which is a part of the limbic system in your brain. The hippocampus is most well known for converting short term memory into long term memory. 

Labeled parts of the brain focusing on the Limbic System

The researcher in this TedTalk explained his studies on the effects of sleep deprivation on this part of the brain using mice. The results of this study showed that the sleep-deprived mice had less memories, and he found that the dendrites of their neurons had less spines. Hold up- you may have no clue what I’m talking about right now because the nervous system was edited out of the AP biology curriculum. In our nervous system (the brain is part of this), we have special cells called neurons. They communicate with each other through cell structures called axons and dendrites. The axon is what is used when a neuron is sending a signal. The dendrite of another neuron will then receive this signal. 

Diagram of a neuron

This particular study, however, mentions the mushroom spines of dendrites which are important for neuronal communication. The more spines there are, the better the connection between the neurons will be. That being said, the researcher found in his study that less mushroom spines are present in neurons in the hippocampus when an individual is sleep deprived, which means that neurons in this part of the brain can not communicate as well. 

Dendrites with mushroom spines (SD=sleep deprived, NSD=not sleep deprived)

This makes sense because the mice had lesser memories after being sleep deprived, as the part of their brain responsible for processing their memory is not at its peak performance. For us, that means that we become more forgetful when we are sleep deprived, which I think most of us have experienced. 

Overall, sleep deprivation is a massive issue in the U.S. According to Johns Hopkins, 6,000 fatal car crashes occur every year due to drowsy driving. That is a horrifying statistic if you think about it because most of the people reading this are my age, so around 16-18. In the state of NJ, a 17-year old can drive without an adult in the car. Many of these new drivers are also sleep deprived, which makes a very dangerous situation, and they are also people you care about. Furthermore, chronic sleep deprivation puts you at a 33% increased risk for dementia according to Johns Hopkins and makes you more at risk for mental illness. 

Some sleep deprivation statistics

The increased risk of getting dementia due to chronic sleep deprivation makes a lot of sense when you think about the glymphatic system. This system works to eliminate waste from the central nervous system, which is your brain and spine. The glymphatic system does this by circulating cerebral spinal fluid, which serves to cushion your brain, facilitate the movement of neurotransmitters, and aid in waste removal. When you sleep, your CSF circulates much better. Essentially, your body gets rid of a lot of harmful waste when you sleep thanks to that increased CSF activity. This is an extremely important feature because it allows your body to get rid of some really harmful substances, such as misfolded β-amyloid proteins. These misfolded proteins are usually present in the brains of Alzheimer's patients. This disease results in severe atrophy of the brain, which is why it is so fatal: it causes severe damage to your body's control system. That being said, if you are sleep deprived, your CSF is not as active as it needs to be, meaning that this harmful protein is not being removed from your brain. People being more at risk to get dementia due to chronic sleep deprivation makes so much sense because without sleep these harmful proteins are not being removed from your body. 

After reading this article, I bet that you are thinking about how you can fix your sleep schedule and become more well-rested. Some of the effects of sleep deprivation that I have mentioned are quite frightening. Fortunately, there are many ways to get more sleep. Cutting down on difficult classes may be a good idea, as well as actually trying to get work done in study hall. This way, you would have more time to sleep because you are taking fewer time-consuming classes and you are eliminating some of that work during the school day. Participating in fewer clubs and sports may also free up more of your time. You could also try taking melatonin before you go to bed. That solution tends to work very well for me most of the time. However, it may be more helpful to try to reset your circadian rhythm by reducing stimulus an hour or so before bed. This can be done by dimming lights, staying off your phone, and staying clear of technology in general. Another solution to this problem is working on not procrastinating. I personally waste so much time doing this. You should seriously consider some of these solutions or think of ones that may work better for you if you struggle with getting enough sleep. Being well-rested is extremely important, and it keeps you safe and healthy!

A Day in the Life of Savannah

          One of the most well known organisms inside Mrs. Eckert's classroom is Savannah, our leopard gecko (Eublepharis macularius). Savannah is our class's pride and joy. She helps de-stress students when we are nervous about an upcoming test, she entertains students by excreting wastes on students, and is just a fun pet for us scientists to explore. Savannah loves to eat super worms! Mrs. Eckert first got Savannah for her freshman students in 2 years ago. At first she wasn't surviving that well, but due to all the student's love and wonderful crickets, she is now surviving great!
          The leopard gecko is originally from the deserts of Asia, throughout Pakistan, and Northern India. During the winter in these areas, the leopard geckos go underground into a semi-hibernation (otherwise known as brumation), where the geckos live on fat reserves (which is stored in their weird tail). In the wild, leopard geckos are crespuscular species which means that they are forced to live in the burrows during the day, but become active at dusk/dawn when the temperature is more favorable. Recently, the leopard gecko has become domesticated. Leopard geckos are thought to be the first domesticated lizard species. 
          Leopard geckos are also bred in captivity, like most other domesticated animals. This means that many people choose a favorable phenotype, so the breeders artificially select that phenotype. Some of these phenotypes include: three different strains of albino, patternless, blizzard, jungle, hypomelanistic, tangerine, giant, and snow. Savannah, however, is none of these strains. 

          The leopard gecko also exhibits sexual dimorphism, which is a phenotype difference between males and females. This is how someone determines the sex of a gecko, which can only be done when they are adults. Female geckos, like Savannah, have smaller pores on their underside and do not have any budges; males have pre-anal pores and hemipenal bulges. Males can identify other geckos by smelling pheromones on their skin. Males respond to other males aggressively, however they respond to females in a friendlier manner (I mean who wouldn't, look at how beautiful Savannah is!) Males and females also have temperature-dependent sex determination. This means that a female gecko is more likely to have a girl if it is in a certain temperature than a boy. Savannah was probably born in either very cold or very warm temperatures (79–84 °F or 93–95 °F). This determination was probably set during two weeks of incubation. 
          Savannah typically has a very exciting day during the school year. She wakes up bright and early with period one AP Bio. They usually are a little cranky due to zero period lab, or the 8 o'clock class start, so Savannah has a quiet morning. She then goes through the day hanging out with Mrs. Eckert and other classes like Anatomy and Physiology. Her day really starts with the start of period 7, where Mrs. Eckert's other AP Bio class comes in. Savannah comes out and hangs out with all the tables, crawling inside binders and on top of classmates heads. Savannah's favorite topic was learning about all of the scientists, her favorite being Rosalind Franklin. Savannah is so popular she even has friends in other classes. One of her best friends, or mother has she likes to believe, is actually a sophomore who has never even been in Mrs. Eckert's classes! She loves taking Savannah home over breaks and probably checks in on her as much as the other students. Savannah is one popular gecko! 

Of Telomeres, Eternal Youth, and Lobsters

If you have taken AP Bio, you will know that when DNA replicates, a small piece is cut off of the end each time (see the following image to attempt to understand, they explain it far better than I could).

Now, as one can imagine, when a piece of DNA is being removed with each replication, the entire strand is going to be shortened more and more over time. DNA replicates hundreds of times in the human lifespan, and it’s pretty unhealthy to lose all that DNA, right?

That’s where telomeres come in. Telomeres are pieces of DNA that hang out on either end of the functioning strand and that do not code for anything at all in the cell’s genes. They’re essentially buffers for the DNA, as when the DNA is replicated, only the telomeres are removed.

Until time runs out. 

There are only so many telomeres — humans can have up to 15,000 base pairs (letters, if you will) in their telomeres. And DNA replication happens frequently. Sooner or later, everyone runs out. And many scientists believe this is a root cause of the human aging process.

Now meet the Lobster.

This guy doesn’t have any of our telomere problems — because he can regenerate his telomeres.

Lobsters possess a special enzyme called telomerase, which rebuilds their telomeres between divisions. This means that no matter how many times a cell divides, it’s nowhere closer to having its DNA destroyed. And the lobsters don’t get old. 

Throughout its life (which can be over 100 years!), a lobster maintains a pretty constant state. His skin (shell?) does not sag and his metabolism does not slow down. They are as youthful as ever, and scientists believe this is because of the benefits of telomerase. Lobsters will eventually die, usually because of predators, but sometimes because they just can't make shells big enough to fit in anymore, but their lives are very different because of this unusual enzyme. 

Now here's where it gets even wilder. Turns out humans have telomerase too -- in children's growth cells, and in cancer cells. Turns out the same enzyme that allows lobsters to stay young is killing millions of people. This weird pattern has generated some important questions: 

Could the lobster be the secret to eternal youth? Could it help us stop cancer?

We’re not sure yet, but these phenomena look pretty interesting nonetheless. Scientists are hoping that telomerase will help us fight cancer, improve skin graft treatment, and, of course, combat aging. Many are working with it right now, and I, personally, am very excited to see where it goes. 

If you want to find out more, check out the following: 
Dr. Joe Dispenza
Smithsonian Magazine