Kidney regenerator cell identified
Zebrafish are renowned in the science community for their ability to repair damage to heart muscle. Now scientists have identified a cell in zebrafish that regenerates the kidneys. The finding could lead to new treatments for kidney failure in humans.
Kidney failure is common in humans as we are unable to generate new nephrons. Nephrons are the basic functional cells of kidneys. They are responsible for regulating concentration and filtering out waste products from the blood.
Though humans can partly repair nephrons, shortly before birth they stop being able to form new ones. Fish, however, are able to keep generating nephrons throughout their lives, producing new ones after kidney damage.
Researchers transplanted progenitor kidney cells — similar to stem cells — to other zebrafish. They were able to track the nephrons produced by these progenitor cells using fluorescent proteins.
They found the transplanted progenitor cells produced new nephrons in the host fish, acting in a similar way to stem cells. Critically, the new nephrons were integrated into the fish's blood supply.
The nephron generation mechanism in the fish resembled that in growing human embryos. This suggests that human kidneys could contain similar nephron progenitors, but they are dormant. Understanding how nephron progenitors work in zebrafish could lead to methods to activate or artificially engineer similar nephron progenitors in humans.
Such treatments will become increasingly important as kidney failure levels rise in line with rising levels of diabetes and hypertension.