What Is Cellular Apoptosis?


Our body contains trillions of cells that carry out several different functions to keep us alive and healthy. When an aging cell becomes worn out and damaged, a process occurs to kill that cell off to make room for a new healthy cell. This process is known as cellular apoptosis.

What Does Apoptosis Mean?

The process of programmed cell death is known as cellular apoptosis. The word apoptosis translates from Latin “to fall off .” Like a dead leaf falls from a tree, our cells die off over time. This falling off is a normal process necessary for growth and development. Apoptosis rids the body of damaged cells that are beyond repair during their normal aging process. 

It is considered an orderly process in which the contents of a cell are packaged into small packets of the membrane. They are then ready to be disposed of by immune cells, similar to trash collection. When cellular apoptosis fails to occur, a tumor can develop. Cancer results from uncontrolled cell division or a lack of proper apoptosis. 

What Are Some Examples of Apoptosis?

Apoptosis is a normal part of human development. One apoptosis example occurs during the formation of our fingers in utero. We have webbed fingers when we are embryos. The cells between our fingers receive a signal to die as part of the process of apoptosis. This programmed cell death is why we are not born with webbed hands and feet. 

Cellular apoptosis occurs during the development of other organisms as well. In the worm known as C. elegans, apoptosis kills 131 cells. It is known which cells will die in order for the worm to develop from a single cell into an adult worm. 

Another example of apoptosis occurs in developing frogs during metamorphosis. Frogs begin as tadpoles, but cellular apoptosis occurs to rid the tadpole of its tail as it turns into a frog. This killing of cells is normal and necessary for the frog’s development. 

What Causes Cellular Apoptosis?

Ten billion cells are made every day to balance those dying during apoptosis in the adult human body. The number is even higher when apoptosis is increased during disease. This programmed cell death commonly occurs as we develop and age to maintain the cells in our tissues. 

Some other stimuli and conditions are known as causes of cellular apoptosis. It is an immune response when cells are damaged by disease or a toxic agent. Chemotherapy causes cellular apoptosis in some cells. Corticosteroids are hormones that trigger apoptotic death in some cells. Other examples of causes of cellular apoptosis are:

  • Ischemia
  • Hypoxia
  • Exposure to certain drugs and chemicals
  • Immune reactions
  • Infectious agents
  • High temperatures
  • Radiation
  • Diseases

What Happens During Cell Apoptosis?

When a cell receives the signal, it will begin the series of coordinated events that mimic cellular suicide. During cell apoptosis, the cell shrinks and pulls away from neighboring cells. It appears that the surface of the cell then begins to boil. Cell fragments break away and escape from the cell. 

The cell nucleus contains DNA that condenses and breaks into even pieces. The nucleus and the rest of the cell disintegrate. Phagocytic cells, known as the cleanup crew, are immune cells that dispose of the dead cells and the debris they left behind. 

What Is Cellular Autophagy?

Cellular autophagy is your body’s way of removing damaged cells while recycling parts of them. The recycled parts of the cell are used to repair and clean other cells. Cellular autophagy helps our cells function smoothly by removing debris and self-regulating. 

Cellular autophagy helps promote anti-aging properties by creating younger cells in your body. It triggers healthy cells to regenerate and provides the energy and building blocks needed for cellular repair. Autophagy may also aid in preventing neurodegenerative diseases like Parkinson’s Disease and Alzheimer’s by removing toxins from the cells that cause these illnesses. Some other benefits of autophagy include:

  • Ridding cells of toxic proteins that can trigger age-related diseases
  • Recycling left-over proteins
  • Providing cells with energy and building blocks for new cells
  • Promoting the regeneration of healthy, new cells

What Is Cellular Homeostasis?

Cellular homeostasis is when several factors are balanced in order to make a cell healthy. Homeostasis is a self-regulating process that promotes the state of equilibrium within a cell. The cell must adjust to changing conditions in order to survive. When the balance within a cell is disturbed, the cell responds to regulate and restore equilibrium. 

The different functions of cellular homeostasis in our bodies can be broken down into three categories. These functions include:

  • Recycling and reusing dead cells
  • Communicating between different operating levels in our body
  • Maintaining our body’s different rhythmic cycles, like the circadian rhythm

Why Is Apoptosis Important for Homeostasis?

Why is apoptosis important for homeostasis? Apoptosis is important for homeostasis because it removes damaged cells in order to maintain a cell’s balance. This removal of damaged cells is fundamental for health and longevity. 

Our body and its 100 trillion cells are constantly changing. Everything from our skin cells to the cells in our stomach lining has a continuous turnover to promote normal functioning. Without apoptosis and autophagy, dead or poorly functioning cell parts would build up and cause an array of illnesses, such as:

  • Cancer
  • Heart disease
  • Advanced aging
  • Organ damage
  • Age-related diseases

Does Apoptosis Cause Inflammation?

Apoptosis triggers an anti-inflammatory response by genes in other cells. Those genes release adenosine monophosphate. The adenosine monophosphate molecule stimulates the A2a adenosine receptor in phagocytes which has anti-inflammatory effects. 

Another form of cell death known as necrosis does cause inflammation. The cell membrane is ruptured during necrosis. Components from the ruptured cell come into contact with nearby healthy cells to cause inflammation. 

Which Cells Cannot Be Killed by Apoptosis?

Apoptosis functions to remove any unnecessary or unwanted cells and is a highly regulated process. Apoptosis can kill cells that are infected with viruses. It can also kill cells that have experienced DNA damage. However, apoptosis cannot occur in cancer cells. Cancer cells are the result of improper regulation of apoptosis. 

Supplements May Help

The autophagy processes in our bodies decline as we get older, but Spermidine supplements can help. They improve your cellular health to promote a healthy life and longevity. These supplements induce autophagy and rejuvenate your cells. 


  • Don Moxley - Director of Applied Science

    Don Moxley is the Director of Applied Science at Longevity Labs. Moxley draws upon his career as an athlete, a sports scientist, and an instructor to lead and educate on the science of autophagy and longevity.