Leprosy is one of the world’s oldest and most persistent diseases, but the bacteria that cause it may have surprising abilities in liver growth and regeneration.
Scientists have discovered that parasites associated with leprosy can reprogram cells to increase the size of the liver in adult animals without causing lesions, scarring or tumors.
The findings suggest the possibility of adapting this natural process to regenerate aging livers and increase lifespan (disease-free life span) in humans.
Experts say it could also help repair damaged livers, reducing the need for transplants, which are currently the only curative option for people with end-stage scarring.
Liver regeneration might be possible with leprosy
Previous studies favored restoring mouse livers by generating stem and progenitor cells (the step after a stem cell that can become any type of cell for a given organ) through an invasive technique that often resulted in scarring and tumor growth , write EurekAlert.
To overcome these harmful side effects, researchers at the University of Edinburgh, Scotland, built on their previous discovery of the partial cellular reprogramming ability of the leprosy-causing bacterium, Mycobacterium leprae.
Working with the Department of Health and Human Services in Baton Rouge, Louisiana, the team infected 57 armadillos (a natural host of the leprosy bacteria) with the parasite and compared their livers with those of uninfected armadillos and those that were found to have be resistant to infection.
What happened to the animals infected with leprosy?
The scientists found that the infected animals developed enlarged but healthy and undamaged livers with the same vital components, such as blood vessels, bile ducts and functional units known as lobules, as uninfected and resistant sires.
The team believes that the bacteria “hijacked” the liver’s inherent regenerative capacity to increase in size and therefore gave it more cells to grow with.
The researchers also found some indicators that the main types of liver cells, known as hepatocytes, reached a state of “rejuvenation” in the infected daddies.
The livers of the infected animals also contained patterns of gene expression (the pattern for building a cell) similar to those in younger animals and human fetal livers.
Genes related to metabolism, growth and cell proliferation were activated, and those related to aging were regulated or suppressed.
A step forward in the treatment of liver diseases
Scientists believe this is because the bacteria reprogrammed the liver cells, taking them to the previous stage of progenitor cells, which in turn became new hepatocytes and grew new liver tissue.
The team hopes the discovery has the potential to help develop interventions for the aging or damaged liver in humans. Liver diseases currently lead to two million deaths per year worldwide.
The findings were published in the journal Cell Reports Medicine.