What Happens When Your Cells Enter the "Matrix" – Part 2

Written by Anil Bajnath, MD
Posted November 4, 2021

Dear Longevity Insider,

A key part in the extracellular matrix is what's called "selective permeability." Many types of tissue have a limited list of molecules that can diffuse across their borders in one direction or another (hence, selective permeability).

Two Main Features of Selective Permeability:

  1. Pores in the plasma membrane allow solutes to move through them but prevent water from moving freely through those pores, due to the presence of lipid bilayers. This allows cells to selectively control which molecules can enter or exit their local environment.

  2. Cells can have a different level of permeability in different directions, so some proteins will move freely across the cell membrane while others cannot – this is called "anisotropy."

How Does Selective Permeability Work?

Different types of cells can adjust how permeable their plasma membranes are to help create local boundaries and also take in the right molecular nutrients for their job. In regards to the extracellular matrix, the ECM can bind to integrins on the plasma membrane of cells, which helps create a boundary that separates tissues from each other.

Integrins are the major cell adhesion proteins, which means they bind cells to the ECM. Cells will be able to pass molecules through the border into neighboring tissues, but if the molecule is too large, it won't fit through the pores of the membranes and therefore cannot go across. All cells have distinct levels of permeability in different directions to help create a very specific environment for each cell type.

Extracellular Matrix & Longevity

Part of what allows cells to remain differentiated is the extracellular matrix. It provides cells with the appropriate molecular signals to maintain their state. When they move to a different tissue, it also helps ensure that they will behave correctly in their new local environment – which is why this system breaks down when there is damage or disease. Abnormalities in the extracellular matrix are linked with age-related diseases. When ECM is broken down, it releases many different molecules that can cause inflammation.

Inflammation is an immune response meant to eliminate threats to the body, but chronic inflammation can be very harmful and eventually result in death. When this happens over time, the extracellular matrix will degrade and build up in ways that are detrimental to our health. When this happens, it causes "inflamm-aging" which is when inflammation builds up over time due to wear and tear on the body.

Promoting Longevity

As we age, the extracellular matrix continues to degrade in many ways. The aging process involves many deleterious changes in the cells and tissues of an organism, which can affect how it functions. Lifestyle factors may accelerate the degradation of the extracellular matrix. Since ECM is responsible for cellular differentiation, preventing this degradation could lead to greater longevity because it would allow cells to maintain their state and continue functioning properly. 

There's another process in the body the essentially degrades your cells and threatens your longevity.

To your longevity,

Anil Bajnath MD
CEO/Founder, Institute for Human Optimization
Chief Medical Officer, Longevity Insider HQ