The Nobel Prize in Physiology or Medicine 2016 was awarded to Yoshinori Ohsumi for his discoveries of mechanisms for autophagy. Our bodies are home to the ultimate recyclers: our cells. Through a complex natural process called “autophagy”, cells break down their old or unused parts and transform them into useful building block to renew themselves. This isn’t just a clean-up—it’s a crucial recycling operation that keeps our cells functioning smoothly and staying youthful.
Autophagy works across all life forms, from yeast to humans, ensuring our cells, can operate effectively, and resilient against aging. It’s a natural, life-sustaining process that shows the power of recycling on a microscopic level. Remember, every time you recycle, you’re mimicking one of life’s fundamental processes. Autophagy is nature’s way of keeping life vibrant and healthy, one cell at a time.
Building on Yoshinori Ohsumi’s ground-breaking work, the scientific community now establised, that autophagy plays a crucial role in maintaining cellular health by degrading and recycling cellular components. This natural process not only supplies energy and materials for cell renewal but is also pivotal in responding to nutritional deficits and stress, fighting infections by removing harmful intracellular pathogens, aiding in embryonic development, and ensuring proper cell functioning. Furthermore, by clearing out damaged proteins and cell components, autophagy acts as a cellular quality control system, vital for mitigating aging effects. This understanding underscores autophagy’s significance across various physiological functions and health aspects.
According to a recent review study in the reputed journal Cell ageing is driven by 12 “hallmarks”, and the impairment of autophagy is a major one, since its loss signals a shift-away from the cellular equilibrium observed in youth. This shift is characterized by an increased accumulation of cellular waste, a consequence of numerous age-related modifications. Furthermore, the efficiency of waste disposal mechanisms is concurrently diminished by a variety of factors. This imbalance, which involves the build-up of waste products alongside a decline in their removal, underscores a pivotal aspect of cellular aging. It emphasizes the importance of research and interventions aimed at reestablishing cellular balance and health.
The connection between autophagy and metabolic health is profound and multifaceted, affecting various aspects of cellular and systemic physiology. It plays a critical role in regulating energy balance, nutrient utilization, insulin sensitivity, lipid metabolism, mitochondrial function, and the response to metabolic stress. Dysregulation of autophagy is thought to be a contributor to a poor metabolic health.
Autophagy plays a multifaceted role in immune health by defending against pathogens, facilitating antigen presentation, regulating inflammation, maintaining lymphocyte (white blood cells responsible for identifying and fighting infection) equilibrium, contributing to immune tolerance, enabling stress responses, and modulating cytokine (signaling molecules of your immune system) production. Through these mechanisms, autophagy supports your immune system, highlighting its importance in maintaining immune equilibrium and protecting against diseases. Dysregulation of autophagy can lead to impaired immune responses, increased susceptibility to infections, chronic inflammation, underscoring the potential of targeting autophagy to enhance immune health, especially in the elderly.
Induction of autophagy is not a “1 pill job”. Inducing autophagy, can be achieved through various lifestyle and dietary interventions and here are some examples:
Fasting or Caloric Restriction: Periods of fasting or reducing calorie intake can trigger autophagy. Intermittent fasting, such as 16/8 or 5:2 methods, or calorie restriction without malnutrition, are popular strategies.
Exercise: Regular physical activity, especially aerobic exercise, can induce autophagy in various organs, including muscle, liver, and brain, contributing to cellular maintenance and function.
Ketogenic Diet: A ketogenic diet, high in fats and low in carbohydrates, can mimic the effects of fasting, promoting autophagy by altering metabolic states and reducing insulin levels.
Limiting Protein Intake: Temporarily reducing protein intake can stimulate autophagy due to the decrease in amino acid availability, which is sensed by cells as a sign to initiate autophagy.
Spermidine supplementation in a physiologically-significant dose: Spermidine, a natural polyamine found in foods like aged cheese, mushrooms, soy products, legumes, and whole grains, has been shown to induce autophagy and may contribute to cellular rejuvenation and longevity. In in the developed world, the average dietary intake of spermidine through foods and without supplementation, is thought to be in the range of 8-12 mgs of spermidine already.
Managing Stress: When the body experiences psychological stress, it activates various physiological pathways, to release stress hormones such as cortisol and adrenaline. Short-term stress can temporarily increase inflammatory responses as part of the body’s defense system. However, ongoing psychological stress can throw the immune system off balance, resulting in sustained inflammation. Chronic stress, whether it’s physical, psychological, or metabolic, can interfere with the body’s usual autophagy process. This interference can hamper the signaling pathways that control autophagy, diminishing the process’s efficiency. Such disruption can lead to the buildup of damaged proteins and organelles, causing cellular dysfunction on multiple levels.