Connective tissue is a fibrous cell-sparse network that helps to connect, support, bind, and separate neighboring tissues from one another.
It exists in and around every organ of the body.
Probably the most recognizable forms of connective tissue are bones (calcified), tendons, ligaments, cartilage, and fats. One major component of connective tissue is the extracellular matrix (ECM), which is composed of various molecules (e.g., proteins) that give structural and communicative support to nearby cells.
Common examples of the ECM include elastins and collagens, the latter the most abundant protein in the human body and which is highly implicated in different forms of Ehlers-Danlos syndrome (EDS) .
there is nevertheless growing interest in EDS, its association with neurodevelopmental conditions like autism and ADHD, and how collagen deficits may play a role in those conditions.
Unlike tendons, for instance, the human brain doesn’t house what one would call “connective tissue” in the traditional sense.
However, ECM in the brain does nevertheless maintain an extensive network that, like other forms of connective tissue, both supports and separates neighboring tissues from one another.
As an example, the ECM supports the growth and establishment of neuronal axons and dendrites and also helps maintain synaptic connections . Interestingly, the local ECM must be degraded and remodeled to allow for synaptic plasticity– a process that’s dependent on neural activity .
Scientists have also found that the ECM forms compartments surrounding neurons that help to limit the diffusion of the excitatory neurotransmitter, glutamate– allowing refinement of those signals between nearby neurons . Without such barriers, glutamate would be allowed to reach more distant neurons, substantially altering patterns of cell communication.
the links between EDS/HSD and various neurodevelopmental conditions like autism suggest collagen may play a larger role than is currently recognized.
We also don’t know if these effects are primarily limited to the early prenatal period, given collagen’s expression within the germinal zone of the developing brain, or if it plays other roles in the mature brain that are currently unrecognized.
But as scientists continue to root out their blindspots, and as interest from patient communities changes, I think the roles of ECM in brain development will continue to receive more and more attention.
I’ve previously posted about collagen:
Fascia is connective tissue:
- Collagen: More Powerful Than Muscle
- Collagens in Energy Metabolism and Metabolic Diseases
- Newly discovered features of collagen
Collagen and EDS: