Simple Summary:

Oxidative Stress damages an important part of our brain cells and leads to cell death.  It may be one of the causes of Alzheimer’s and Parkinson’s.

More Detail:

This paper from researchers at the University of Georgia in 2015 has the long and sexy title Myxococcus CsgA, Drosophila Sniffer, and human HSD10 are cardiolipin phospholipases.   They start by looking at processes within bacteria and move on to their research on mitochondrial damage.  Your first thought may be along the lines of “huh?” but our mitochondria are generally believed to be co-opted bacteria from long long ago, so discussing both in the same article isn’t that far fetched.  In fact, a bacteria living on the surface of the ocean shares a relatively recent common ancestor with the mitochondria existing in most eukaryotic cells.  And eukaryotic cells are (I promise we will get to the main point in a moment) different from simpler cells because they have little enclosed packages inside the cell called organelles, of which the mitochondrion is one.

The researchers found how a protein protects against cell death.  It’s not a long paper, but the chain of logic is best followed if I use bullet points.

  • The protein (in this case an enzyme) is HSD10 which has several functions, but here we are focused on it’s ability to detoxify cardiolipin
  • Cardiolipin – first found in the 1940’s while studying a cow’s heart, is integral to mitochondria, where it surrounds and protects the energy-making machinery from oxidative stress
  • When cardiolipin itself becomes oxidated it forms cardiolipin peroxides
  • Cardiolipin peroxides, in turn, trigger cell death (apoptosis)
  • HSD10 degrades highly toxic cardiolipin peroxides and prevents cell death
  • HSD10 is greatly inhibited by Amyloid-beta

That last bullet point brings us to our connection with Alzheimer’s.  Amyloid-beta is a hallmark of Alzheimer’s disease.  The implication here is that Alzheimer’s may result when Amyloid-beta binds with HSD10 and prevents it from repairing cardiolipin.  The damaged cardiolipin then trigger apoptosis.  Cell death on a large scale would result in neurodegeneration.

Remember always that this is a piece of the puzzle and that correlation does not imply causation.