Introducing the liver (Introduction)

by David Turell , Tuesday, May 31, 2022, 19:10 (907 days ago)

The largest organ in the body detoxifies lots of pleasant and unpleasant substances. As a result, it constantly regenerates:

https://medicalxpress.com/news/2022-05-liver-years.html

"The liver is an essential organ that takes care of clearing toxins in our bodies. Because it constantly deals with toxic substances, it is likely to be regularly injured. To overcome this, the liver has a unique capacity among organs to regenerate itself after damage. Because a lot of the body's ability to heal itself and regenerate decreases as we age, scientists were wondering if the liver's capacity to renew also diminishes with age.

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"The interdisciplinary team of biologists, physicists, mathematicians, and clinicians led by Dr. Bergmann analyzed the livers of multiple individuals who died at ages between 20 and 84 years old. Surprisingly, the team showed that the liver cells of all subjects were more or less the same age.

"'No matter if you are 20 or 84, your liver stays on average just under three years old," explains Dr. Bergmann. The results show that the adjustment of liver mass to the needs of the body is tightly regulated through the constant replacement of liver cells and that this process is maintained even in older people. This ongoing liver cell replacement is important for various aspects of liver regeneration and cancer formation.

"However, not all the cells in our liver are that young. A fraction of cells can live up to 10 years before renewing itself. This subpopulation of liver cells carries more DNA than the typical cells. "Most of our cells have two sets of chromosomes, but some cells accumulate more DNA as they age. In the end, such cells can carry four, eight, or even more sets of chromosomes," explains Dr. Bergmann.

"'When we compared typical liver cells with the cells richer in DNA, we found fundamental differences in their renewal. Typical cells renew approximately once a year, while the cells richer in DNA can reside in the liver for up to a decade," says Dr. Bergmann. "As this fraction gradually increases with age, this could be a protective mechanism that safeguards us from accumulating harmful mutations. We need to find out if there are similar mechanisms in chronic liver disease, which in some cases can turn into cancer.'"

Comment: viewing this from a design perspective, this is exactly what a designer would design knowing the toxic functions of the liver. This is not something the liver cells should figure out on their own over time. Livers need to survive and do their job from the very beginning. This is a way to show that dhw's intellgient cell committee theory can't work. Committe work is not instantaneous as it needs be.