Medicine has come so far that the average life expectancy is doubled what it was in the year 1900s. Today, we are living longer than ever, better at catching and dealing with diseases.
To understand can humans live forever, we need to understand how actually humans live. What happens in our body as we live, particularly as we age? The changes in our body as we age. If we can understand and study this, the potential to someday replicate or reverse this process may not be far.
“Jeanne Calment, a French woman passed away in 1997 at the age of 122 years and 164 days, making her the oldest lived recorded person in history.”
WHY DO OUR BODIES AGE?
Think of ourselves as cars. Parts wear down by friction, rubbing, grinding. Metals get rusted, tires are worn off, filters get chocked, rubber gets cracked. Likewise, our bodies are worn down by millions of tiny physical processes right from the cellular level. Our body has mechanisms to repair these, but over time, these get weaker and our body wears down.
Aging happens as a result of our body's interaction with our environment, air, water, our diet which eventually changes the structure and function of molecules and cells in our body. Eventually driving our body to perform low, failure to some or whole organs, decline in capacity to build cells and a total decline of our body causing death.
9 PHYSICAL CHANGES THAT CAUSES BY AGING
HEART
Our heart pumps 2.5 billion liters during our lifetime. With this, the blood vessels lose their elasticity and fat start to deposit on the walls of these vessels. This makes the heart to work harder to pump the same amount of blood leading to increased blood pressure and stroke.
BONES, JOINTS & MUSCLES
As we age, the density of our bone decreases. This mainly happens as our bone which is made up of calcium starts to chip away. This leads to fracture, loss of strength, pain in joints, muscle ache, etc.
DIGESTIVE SYSTEM
In order for digestion to take place smoothly, certain gland secretion should take place. Over time, the flow of this reduces and digestion in the stomach becomes harder. Even contraction in our esophagus (swallowing) becomes painful and difficult.
KIDNEY & URINARY TRACT
Our kidney shrinks as we age, this makes it less efficient in the waste removal process. The main reason for shrinkage is the loss of cells as we age.
BRAIN & NERVOUS SYSTEM
We naturally lose cells as we age. We tend to lose memory over time because the number of cells in our brain decreases, thus the number of synaptic connections starts to break away.
EYES
Our lens or cornea tends to stiffen up as we age. This makes us difficult to navigate or recognize objects in low light conditions. Cloudiness can form in our lens and over time causes blurriness to our vision.
EARS
Our hearing range is from 20Hz to 20,000 Hz. Over time, due to excessive noise and high-pitched noises can cause hearing loss. There are cases of accumulation of excessive ear wax.
HAIR & SKIN
More wrinkles start to show up as we age because our skin expands and contracts all the time. Hair grows slower as we age and becomes thinner and grey. The fat layer under our skin thins up causing less sweat secretion. This can be good, but it also causes exhaustion and tiredness in summer situations.
WEIGHT
Lower level of physical activity and metabolism can eventually gain you more weight. These extra calories will not be burned up, so these get as accumulate fat.
BIOLOGICAL CHANGES THAT CAUSE AGING IN OUR BODIES
GENETICS
As we grow old or age, our bodies accumulate genetic damages in the form of DNA legion. Let’s see from the cellular level. Mitochondria are called the powerhouse of a cell. It produces ATP (Adenosine triphosphate) which keeps the cell alive and active throughout its lifespan.
Mitochondria play an important role in the functional activities of the cell and also in programmed cell death. If mitochondria’s function starts to decline, so will all the cells start to die. The fact that cell needs to replicate after a certain period time keeps us up and active (growing). This cellular replication, the heart of life starts to decline as we age.
The DNA of our cell has the instruction book called a chromosome. These have a protective layer at the end called telomers. These shorten every time the cell replicate. When these become too short, the cells stop replicating. These become zombie cells often called senescent cells. This cell type typically does not die and keeps on accumulating as you grow old. They harm the tissues around them and cause many diseases related to diabetics, kidney failure, etc. Slowing the body’s ability to renew.
One other factor is the quality control that happens inside the cell. This slows down as we age and excessive toxic proteins start to accumulate in the cell- leading to the death of the cell. Intercellular communication also slows down thereby hindering the body’s ability to do internal function.
SENESCENT CELLS
Scientists genetically engineered mice so that they could kill all of their senescent cells. This resulted in a more active, more functional heart and kidney, which was less prone to cancer. These mice lived 30% longer and were in better health than the average mice. This is a pretty difficult challenge in the human body as we have 70 trillion cells in our body to genetically engineer, which will be a whole different challenge.
NAD+ (Nicotinamide Adenine Dinucleotide)
NAD+ is a coenzyme that tells the body to fight disease and stay healthy. Here the cell does a lot of function in order to keep it alive and growing. The NAD+ see to all these functionalities. As we grow old, the amount of NAD+ varies significantly. At age 50, we have only half as much in our bodies as we had in age 20. The lower amounts of NAD+ are linked with Alzheimer’s disease, skin cancer, cardiovascular disease, multiple sclerosis, etc. But finding a way to increase the amount of NAD+ in our body as we age could be the next anti-aging pill.
STEM CELLS
Stem cells have the ability to copy themselves to produce a uniform flow of fresh young cells. These stem cells act as blueprints to our existing cells. But this steady flow declines as we age. Without new cells regeneration, our body starts to break, bringing new diseases and pain to our body.
EPIGENOME
Our body has the same DNA in all the cells. The DNA is what instructs the cell to do particular functions. Different cell types have different functions; thus, the DNA is packaged differently to enable different functionality to the cell. This packaging is done by epigenome. What epigenome does is to coil up around our DNA so that it's not read and leaving some spool out so those spools can be read and instruct the cell to make proteins for the cell to function. So, basically epigenome turn’s ON and OFF certain parts of the DNA. This is important because if a skin cell needs to be a skin cell, the epigenome is the one who instructs it to be.
With age, the epigenome performance deteriorates and it no longer functions correctly. It forgets what the cell actually is (e.g.: skin cell to be skin cell) and how it should perform. This irregularity mostly leads to irregular functions in our bodies. We see weird skin patches in our body, weird changes in our physical body, all these are associated with epigenome. E.g.: hair growing where it shouldn’t, like in places of ears, nose, back. Those are the cells losing their identity and no longer function correctly.
HORVATH CLOCK
So, there are these plaques that get accumulated on our DNA as we age. So, the more you have, the older you're biologically. If we can read the amount of this accumulation, we can read the biological age you’re in right now. You may be physically 27, but biologically you may be aged 44 (due to various factors such as obesity, drinking, smoking, stress).
WAYS TO LIVE LONGER OR SLOW THE RATE OF AGING
Avoid DNA Damage: This can be done by making yourself less exposed to radiation such as UV rays, X rays, sunlight, etc.
Eat less: Having intermittent fasting and cutting down the time you eat (cutting down calories) you can restrict hunkering of the mTOR gene which is one of the longevity genes.
High Intensity Interval Training (HIIT): Get your heart rate pumped up to 85%, maximize your lung capacity for the longer proper working of your organs.
Be uncomfortably cold and be uncomfortably hot: This releases defense hormones and suits your body to sustain more heat or cold, basically strengthen our cells and DNA.
All these will trigger your body’s longevity genes into maintaining your epigenome, going into repairing and protecting mode.
STEM CELL REGENERATION
Now you know what stem cell does. Scientists were able to take fresh stem cells from young mice's brains and inject those into an older mouse's brain, particularly into the hypothalamus. Thus, these fresh cells rejuvenated older brain cells by secreting micro-RNA’s that regulated their metabolism. After few months, the brain and muscles worked better than those of untreated mice and they lived 10% longer. The same was done into the hearts of older mice. This increased their heart function, exercise 20% longer and their air grew faster.
REVERSING THE AGING PROCESS
We know that as we age, our epigenome forgets the instructions to be given to the cell to perform correctly. What if we have a way to reset this epigenome so that it can function normally just like it was in the initial stage, like a reset button to the epigenome. In 2012, a scientist named Yamanaka received Nobel prize for discovering four factors when applied in a gene therapy to an adult cell that can reset our epigenome back to the stage where it was when in an embryo stage. This resetting of the epigenome might be the key to reverse aging.
Experiments to reprogram the eye of a mouse- from blind to fully functional eyes have been successfully done. But think about resting this not once, but any number of times you want. This, if human trials succeed, be the new revolution to treatment and aging reset.
The immortal jellyfish (moon jellyfish) has this ability to reset all of its cells and go back to the earlier stages of its life cycle- to become a polymorph again. If we could study and understand how the jellyfish does, maybe we could also do the same in ourselves. The problem with us is, we have trillion cells and resetting each cell will turn into a giant tumor- which probably is not a good idea.
WHY DO WE CHOOSE MICE FOR EXPERIMENTS?
By now, you must be wondering why all the lab tests are done on mice. Their genetic blueprints are similar to our’s and 90% of genes associated with the disease are identical to humans and mice.
UNDERSTANDING OUR BRAIN
MIND UPLOADING
What is this mind? Is it our brain, our memories, conscious abilities? Well, it’s all of them. Memories form in our brain through synaptic connections and we think and do tasks through our conscious brain while all the body activities like cell growth, heartbeat, kidney function, organ function keep on doing by our subconscious mind. So, what part of this is actually necessary if we want to take it forward once we die.
The answer might be complex than we think, but let’s understand the part where all this happens- the brain. Our brain is the most complex biological structure known to mankind. There are 100 billion neurons that are communicating via 1 million billion connections sending signals up to 1000 signals/second. This is one quad trillion (1x1015) events every second of your waking life. Upon this, there are billions of immune cells and supporting cells doing their job to keep our brain functioning. Additionally, there are hormones called serotonin which affects our mood and histamine which helps us learn.
The right side of our brain deals with creativity, intuition, holistic thoughts while the left side deals with logic, reasoning and scientific skill. Our brain, which only accounts for 2% of our body mass consumes 10% of our daily glucose burned. In children, it's 50% and for infants, it's 60%. That’s one of the reasons why children are quite hungry always and learn things faster.
MAPPING OUR BRAIN
Mapping is something like creating a road map of our brain’s connection. The structural part is getting to know the physical connection (Synaptic connections) between these neurons and the function part is to know the functionality of these neurons across brain regions. Thus, to map the structural and functional part is our goal to get a full map of our brain.
One way to scan our brain is to cut down it into tiny slices and scan them with a high-resolution electron microscope to create an accurate map of all the cells and connections.
In 2019, scientists were able to map a cubic millimeter of mice brain, roughly the size of a grain of sand. It contained 100,000 neurons with billions of synapses and four kilometers of the nerve fiber. The brain was cut into 25,000 slices, 40 nanometres wide (1/5th of our hair strand), scanning the brain by 5 powerful electron microscopes which ran continuously for 5 months collecting 100 million images. It took 3 months to assemble these images into a 3D model structure taking 2 million gigabytes of storage. If we were able to scan our brain, which is 1000 times bigger than a mouse's brain, it would take up 2 million petabytes (2x1015 MB) of storage.
But in order to correctly map our brain, we might need to map at the cellular level which might take more data than the capacity of all data storage on earth. So, storage-wise, our technology is nowhere. Suppose we got the data; how do we turn these images or 3D models into an active thing. For these, we might need to establish rules and laws on how the synapses get connected, signals getting transferred for a systematic approach to simulate our brain, or at least animate what is in our mind.
Successful mind uploading will be a road to immortality unless damaged, corrupted or deleted. This copy will continue to exist as long as the copy is somewhere safely stored. If this happens, the biological you and digital you can coexist, you could help each other out learning, teaching for a secured future for both.
TECHNOLOGICAL WAYS TO LIVE LONGER
ROBOTIC BODY
In order for us to be into a robotic body, we need to successfully map our brains. To be able to understand what’s going on inside our brain, since the information is encoded in the synaptic connection between neurons in our brain. To successfully download our brain, these 100 trillion connections need to be precisely scanned, mapped and digitally restructured on a computer as an artificial brain. This simulation would not only behave like a biological brain but retain our thoughts and memories. For now, we are a long way into mapping our brains. Our technology has just not progressed enough to attain these fleets of achievement yet.
3D PRINTED LIMBS AND ORGANS (BIOPRINTING)
In 1800, scientists were growing cells in glass Petri dishes. From then, we have now come to 3D print which itself is another dimension. A revolution has started for lab-grown organs for transplant. Researchers in Israel’s Tel Aviv University were able to successfully 3D print a replica of a heart (with blood vessels, cells, tissues) from a patient’s fat tissue cells. For patients with transplants, our body rejects them if we get organs from donors- for kidneys, it's 20% and for heart, it's 40%. This technological revolution could potentially prevent early death or suffering or could possibly make a person live forever.
CRYOGENIC FREEZING
Can you actually freeze yourself in one time and come back alive at a later point (50-100 years) down the line? Cryogenics is rapid freezing and then storing a person in liquid nitrogen. Once you die, your body will be stored in ice (liquid nitrogen) and your blood will be replaced with cryoprotect (solution designed to keep ice from forming in your cell). There are companies that do this for $100,000- just the head part. But these are done in the hope the future technologies will someday be able to retrieve information in these cryogenic freeze brains and bring their thoughts and memories back to life through a robot or possibility using actual human parts.
CREATING A VIRTUAL WORLD
This comes after the possibility of your brain successfully being uploaded into a computer system. From these, imagine there is a world where you can do all the things which you’re doing now in this physical world-eat, sleep, play, read, have a conversation, a normal life- but it's just virtual. But since you’re in a computer simulation, you might age as normal or not age at all, die or live forever, the possibility is endless. Each day we are looking towards a world full of virtual connections and COVID-19 has given us a glimpse of it.
CYBORGS
Think of having your brain intact and all your other body parts are electronically controlled, you might need to change yourself once in a while, but you still have your biological brain to process all the information and think consciously. You’re living in your physical world, but it’s just not the complete you. To control objects with your mind, hear color or live forever could be the next level cyborgs we could see in the coming human evolution. The way we see the advancement of Artificial Intelligence now, which can replace our jobs in the future, there is a good chance to see fully independent living cyborgs in the future.
NEURALINK
This is founded by Elon Musk, whose aim is to solve important brain and spine problems with seamlessly implanted devices. You could basically implant a device inside your head and look totally normal- solve really important problems with your body, particularly the brain and spine. This could potentially help you to live longer provided your other body parts function normally.
CELL REPAIRING NANOBOTS
Nanobots would be able to repair damaged DNA and allow our cells to function correctly. They have the ability to grab, analyze and fix an individual DNA molecule. The DNA molecule gets attached to the nanobot's surface thereby it scans nucleotides, seeking for damaged fragments. An invalid fragment is removed and the DNA is repaired. This could potentially restore our bodies to a more youthful condition.
DO WE REALLY WANT TO LIVE FOREVER?
Health is the most valuable thing we have in our life. Our generation is living longer than ever before. This also means as we get old, we spend most of our time sick or in pain. The unforeseen challenges in our life put ourselves in this situation. So, we need to shift our focus on the lifespan, where we can live healthy and prolonged life. But will intense feelings of stress and pain go away if we live longer? If you could choose right now, to live in good health with your friends and families or to live forever in pain, misery, disease, stress.
What would your personal answer be?
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