Autophagy is a metabolic process by which cells process waste materials like damaged proteins and by-products of metabolism.
This clean-up process is essential to remove waste materials and make space for newly produced cells and proteins in the body.
This process is intensified when the cell is under stressful conditions- for example in conditions deprived of nutrients or growth factors.
The evolutionary significance of autophagy
One of the reasons for the increased life expectancy of humans is their ability to respond better to biological stress factors.
A recent study showed that small adaptations to the protein p62, which is responsible for inducing autophagy is the reason for this.
P62 activates autophagy when the metabolic by-products begin to accumulate in the cells.
These by-products could cause cellular damage if allowed to build-up over a long time.
Once the waste material is removed, the cell becomes better equipped to deal with biological stress.
The Benefits of Autophagy
Autophagy Can Extend Lifespans
Autophagy restricts age-related build-up of damaged cell organelles. This in-turn improves the metabolic efficiency of cells.
For example, mitophagy is the removal of the cell organelle mitochondria after it has become dysfunctional.
Mitochondria is the energy unit of the cell and produces a lot of reactive oxygen species that degrades the cell.
This maintains the cell integrity and keeps it metabolically sound and active for a longer time.
Protection Against Psychiatric Disorders
Autophagy provides protection against the development of psychiatric disorders. Disturbances to autophagy have been linked to increased risk for certain psychiatric conditions.
Post-mortem studies on the brain of individuals with depression and schizophrenia identified inadequacies in essential autophagy pathways.
Autophagy Prevents Neurodegenerative Disorders
Many neurodegenerative disorders arise from the accumulation of damaged proteins in the neurons. This could induce gradual brain cell death and eventual loss of mental abilities.
Autophagy protects the cells by cleaning-up these proteins.
Some examples of damaged proteins in neurodegenerative disorders that are removed by autophagy:
- Huntingtin (HTT) protein in Huntington’s disease
- APP protein that produces amyloid in Alzheimer’s disease
- ⍺-synuclein (SNCA) in Parkinson’s disease
- microtubule-associated protein tau (MAPT) in dementia
Fighting Against Infectious Diseases
Autophagy helps fight infectious diseases by:
- Direct removal of microbes from the cells (xenophagy)
- Removal of toxins produced by infections
- Regulation of the immune response to infections
Microbes like Mycobacterium tuberculosis and Streptococcus, viruses like HIV, and protozoans are removed by autophagy.
Autophagy can both increase and decrease inflammatory responses in the body.
It increases inflammation turning on the immune response to invading pathogens, and reduces inflammation by cleaning the antigens from the cell.
Additionally, autophagy also removes pro-immune response molecules produced by the cell in response to an invasion
Improves Muscle Performance
When exercising we place a stress on our cells, energy use goes up and components get worn out faster.
Autophagy is increased in response to wear and tear associated with workout. This helps to:
- maintain energy balance in the cell
- reduce the requirement of external energy
- ensure that degraded cellular materials are removed before they become detrimental.
Involvement In Prevention Of Cancer
Autophagy may inhibit the growth of early-stage cancers.
Autophagy suppresses pro-tumour processes like chronic inflammation, dysfunctional DNA damage response, and genomic instability.
Mice DNA, genetically engineered to have damaged autophagy, are reported to have increased rates of cancer
How You Can Increase Autophagy?
Fasting is a powerful way to stimulate autophagy.
Exercise (High intensity interval training - HIIT)
Physical activity boosts autophagy in the brain and other cells in our body.
Studies have shown that autophagy is under the control of the body's circadian rhythm. Erratic sleep-wake cycle and exposure to blue light from screens at inappropriate times disrupts the circadian rhythm, which in turn disrupts autophagy.
Regulating protein intake
Excess protein intake could reduce autophagy. People who diet, especially of the low carb variety, may indulge in excessive protein intake. This should be replaced by plant-based healthy fats. Protein moderation is key to maintaining autophagy.
The ketogenic diet is a low carbohydrate diet that encourages intake of healthy fat and moderate protein. It is a powerful stimulator of autophagy. This could explain why ketogenic diets are being used to fight chronic health conditions including cancer and neurodegenerative disease.
Foods that Boost Autophagy
- Green Tea
- Coconut Oil
- Reishi mushroom
Natural Supplements that Increase Autophagy
- Medium-chain Triglycerides (MCTs)
- Vitamin D
- Omega 6 and 3 Polyunsaturated Fats