In the mythical tales of ancient Greece, Prometheus, the daring Titan, stole fire from the gods and bestowed it upon humans. For this, Zeus ruthlessly punished him by having an eagle feast on his liver which regenerated daily. It is an age-old story that strangely mirrors the incredible ability of our livers to bounce back from damage. The human liver can self-heal to some extent if a liver condition is identified and treated during its early stages.
“It is a process that happens in response to any form of liver damage,” says Dr Chetan Ramesh Kalal, program director of adult hepatology and transplant medicine, center for liver, pancreas and intestine transplantation, Nanavati Max Super Specialty Hospital, Mumbai. The process is initiated whenever the liver tissue requires repair.
When does the liver regenerate?
Dr Pradipta Kumar Sethy, gastroenterologist, department director of gastroenterology, Medica Super Speciality Hospital, Kolkata. Dr Sethy explains that whenever there is an injury, acute viral infection, chemical injury, drug overdose or post-surgery when a part of the liver is removed, the liver tissue regenerates so it can go back to its original state.
Experts add that liver regeneration is a complex process involving the activation of multiple cytokines, growth factors, and signaling pathways that work in perfect harmony to ensure the optimal growth of the remaining hepatic lobules (microscopic divisions of the liver that form the main mass of the hepatic substance). Simultaneously, liver cells continue to function while undergoing mitosis to reestablish the organ’s mass.
According to Dr Sethy, the liver starts regenerating in a few hours. “Within a few minutes to an hour, there is an activation of genes, then there is activation of growth factors,” he adds.
Phases of liver regeneration
Regeneration of the liver happens in phases. The three phases are:
- The initiation or priming phase, which gets triggered by an injury, loss of liver tissues or surgery. “This will signal certain molecules or pathways to initiate the process of liver regeneration,” says Dr Kalal.
- A proliferation phase follows, in which the cells in the liver tissues rapidly multiply to replace damaged cells and restore liver mass.
- The third and final one is the termination phase, in which the entire process will be terminated on its own after the complete regeneration of the liver tissues to prevent excessive growth.
Eight factors that affect liver regeneration
1. Extent of liver damage
“The severity of liver damage due to chronic conditions, infections, or toxins, directly impacts the regenerative capacity,” says Dr Kalal. Severe damage may impede the liver’s ability to regenerate fully.
2. Underlying liver disease
Experts add that pre-existing liver diseases, such as cirrhosis or fatty liver disease, can hinder regeneration. “In advanced stages, cirrhosis replaces healthy tissue with scar tissue, affecting the organ’s regenerative potential,” adds Dr Kalal.
3. Alcohol consumption
Excessive alcohol intake affects liver health. “Regular alcohol intake would hamper liver regeneration. There will be scarring and inappropriate regeneration because of it,” says Dr Pradeep.
4. Genetic factors
Genetic factors play a role in determining individual variations in liver regeneration. “Some individuals may have a genetic predisposition that affects the efficiency of the regenerative process,” says Dr Kalal.
5. Age
The efficacy of liver regeneration can be influenced by the aging process. Experts explain that while the liver retains regenerative capacity throughout life, the process may slow down with age, potentially affecting recovery after injury.
6. Diet
Adequate nutrition is essential for optimal liver function and regeneration. Experts point out that refined carbohydrates and unhealthy fats could adversely affect liver health and also lead to the onset of fatty liver disease (if not treated on time could damage the liver tissues and cause cirrhosis and liver failure).
7. Drug and medication effects
Experts explain that certain medications and drugs can have hepatotoxic effects, directly impacting liver cells and hindering the regenerative process. The liver is responsible for flushing out the toxins from your body and hence excess chemicals from these drugs could adversely affect your liver health.
8. Health co-morbidities
“Conditions such as diabetes and metabolic syndrome can influence liver health and regeneration,” says Dr Kalal. He also adds that insulin resistance and metabolic disturbances may contribute to liver damage due to factors like excess visceral fat deposition on the liver. He also adds that chronic viral infections that affect the liver, particularly hepatitis B and C, can lead to ongoing liver inflammation and damage, impacting the regenerative capacity of the liver.
Benefits of liver regeneration
Liver regeneration is essential for maintaining optimal liver function and overall health. However, experts add that regeneration also depends on the individual. “If the person has a healthy liver, then the chance of recovery is better,” says Dr Sethy. One can maintain a healthy liver by exercising, reducing the consumption of alcohol, quitting smoking, maintaining a healthy diet and lifestyle, and going for regular checkups and follow-up tests with the doctor.
Takeaways
- The liver has the unique ability to regenerate.
- It happens in response to an injury, acute viral infections, chemical injury, drug overdose, or post-surgery.
- Liver regeneration happens in three phases — Initiation, proliferation and termination.
- The chances of recovery are better if one’s liver is healthy.
