Most conversations about brain health center on what’s happening inside neurons, like the electrical signals, the neurotransmitters, and the synaptic connections. But an emerging body of research is pointing to something more foundational: the health of the tiny blood vessels that supply the brain, and the microscopic protective layer that lines them.

That microscopic protective layer is called the endothelial glycocalyx, or EGX. What scientists are discovering about its role in brain function may reshape how healthcare providers and health-activated individuals think about vascular and brain health.

Key Takeaways

• The endothelial glycocalyx lines the blood vessels of the blood-brain barrier, where it acts as a protective interface helping maintain the stable environment healthy brain function requires.*
• The brain has a higher concentration of endothelial glycocalyx (EGX) than any other organ in the body.*
• The EGX naturally thins over time, and a 2025 study published in Nature found that this is associated with shifts in blood-brain barrier function. 
• A 2025 study found that rhamnan sulfate — a compound derived from the seaweed Monostroma nitidum supported healthy brain tissue structure and healthy brain function.* 
• Arterosil HP® uniquely contains rhamnan sulfate from Monostroma nitidum, formulated specifically to support the endothelial glycocalyx.*

What Is Microcirculation, and Why Does It Matter for the Brain?

Microcirculation refers to blood flow in the smallest vessels in the body. These microscopic vessels can be so tiny that blood cells may only pass through one by one. Despite their small size, they have the critical responsibility of ensuring the final delivery of oxygen and nutrients directly into the organs and tissues. 

In other words, in order for healthy function of any organ (including the brain) it needs proper oxygen and nutrient delivery that can only be supplied through microcirculation. 

The brain is one of the most metabolically demanding organs in the body. It accounts for roughly 20% of the body’s total oxygen consumption, despite representing only about 2% of body weight. That demand is largely met through microcirculation, the tiny blood vessels responsible for delivering oxygen and nutrients to the brain, and clearing waste away. When microcirculatory function is well supported, brain cells have what they need to maintain healthy signaling, energy production, and overall function.*

This is why vascular health and cognitive health are so deeply connected. It’s not just about large arteries and heart function. The quality of circulation at the microvascular level plays a central role in supporting how the brain functions.*

What is the Endothelial Glycocalyx?

The endothelial glycocalyx is a slippery, gel-like lining inside of all 60,000 miles of blood vessels in the body – including the tiniest vessels. It is the body’s ultra-smart vascular lining: an active, protective blood vessel barrier that helps maintain smooth blood flow, balanced fluid exchange, and vascular protection.*

The endothelial glycocalyx acts as a shield and gatekeeper, protecting blood vessel walls and helping regulate what passes in and out of the bloodstream. In everyday language, it’s the vessel’s protective bouncer—the front line of vascular protection and a finely tuned barrier that keeps circulation moving smoothly. 

The Blood-Brain Barrier and the Role of the Endothelial Glycocalyx

Scientists are discovering more about the glycocalyx (EGX), and its role in the brain’s health. In fact, research suggests that the glycocalyx may be one of the brain’s most important protectors.*

The EGX directly supports one of the brain’s most important structural features, the blood-brain barrier (BBB). The BBB is a selective interface between the bloodstream and brain tissue that helps maintain a stable environment for healthy brain function. The BBB controls which substances enter the brain and which are kept out.

Like all blood vessels in the body, the blood vessels that feed the BBB are lined with an endothelial glycocalyx (EGX). Research published in Scientific Reports (Ando et al., 2018) found that the blood vessels in the blood-brain barrier require more endothelial glycocalyx than other organs, including the heart or lungs. 

In other words, the brain relies on a particularly robust EGX to help maintain the blood-brain barrier and support the stable environment that healthy brain function requires. This is a core finding that positions EGX health as central to brain health.

What the Research Says about Brain Health and the EGX

Recently, more research has been published outlining the importance of the endothelial glycocalyx (EGX) in the brain, including how supporting the endothelial glycocalyx (EGX) may also support brain health.*

Study 1: The Brain Has More Glycocalyx Than Any Other Organ

Ando et al., Scientific Reports, 2018

Researchers examined the structure of the capillary endothelial glycocalyx across multiple organs and made a striking discovery: the brain’s capillaries are uniquely rich in glycocalyx, more so than those in the heart or lungs. Their conclusion: “The endothelial glycocalyx is crucial for maintaining brain homeostasis.”

The brain appears to rely on a particularly robust EGX, likely because the blood-brain barrier demands a more developed protective interface than other organs require. The research suggests that supporting the EGX may be foundational to supporting brain health.*

Study 2: Time Naturally Affects the Glycocalyx — and the Blood-Brain Barrier Along With It

Shi et al., Nature, 2025

This landmark study examined how the glycocalyx changes over the course of a normal lifespan and what those changes mean for the brain. The key finding:“Glycocalyx dysregulation impairs blood–brain barrier in aging.”

As the EGX naturally thins over time, its ability to help maintain the blood-brain barrier’s integrity may shift. The study underscores that supporting EGX integrity becomes an increasingly important consideration for healthy brain function across the lifespan.

Study 3: Rhamnan Sulfate from Monostroma nitidum May Support Cognitive Function

Miwa et al., Marine Drugs, 2025

This 2025 study examined rhamnan sulfate (RS), a sulfated polysaccharide derived from the seaweed Monostroma nitidum, and its relationship to brain health. Rhamnan sulfate has been studied for its structural affinity with the endothelial glycocalyx, and the researchers found that rhamnan sulfate from Monostroma nitidum supported healthy brain structure and healthy brain function.* The study’s authors concluded that these mouse model findings suggest RS intake may support overall brain function.*

For a more complete picture of the current research on the endothelial glycocalyx and brain health, you can easily search the topic on PubMed.

Arterosil HP Uniquely Contains Rhamnan Sulfate from Monostroma nitidum

Across all three studies, a clear picture emerges: the endothelial glycocalyx plays a central and underappreciated role in supporting the brain, the blood-brain barrier, and healthy brain function.*

Arterosil HP contains rhamnan sulfate derived from Monostroma nitidum, which is the precise seaweed studied in the 2025 research. 

Arterosil HP with MonitumRS® supports the endothelial glycocalyx.* MonitumRS has been scientifically shown to protect and restore the endothelial glycocalyx.*†

†As demonstrated in an independent third-party laboratory in vitro study.

The Bottom Line

The connection between microcirculation and brain health is more direct and specific than most people realize. At the center of that connection is the endothelial glycocalyx: a thin but critical protective layer that lines the blood vessels of the brain in greater concentration than anywhere else in the body. Multiple studies are converging on the same conclusion: supporting the EGX may be a meaningful step individuals can take as part of a broader vascular and brain wellness plan.*

Frequently Asked Questions

What is microcirculation and how is it different from general circulation? 

General circulation refers to blood moving through the entire cardiovascular system from the heart and large arteries all the way to the tiniest vessels. Microcirculation is a subset of circulation, and describes blood flow specifically through the smallest vessels: capillaries, arterioles, and venules. These are the vessels responsible for the final delivery, where oxygen and nutrients are actually exchanged with tissues. 

Why is the blood-brain barrier relevant to brain health? 

The blood-brain barrier (BBB) is a selective filtering system that separates circulating blood from brain tissue. It helps maintain a stable internal environment for healthy brain function by controlling what enters and exits the brain. The endothelial glycocalyx lines the blood vessels of the BBB, and research suggests that EGX integrity plays a meaningful role in supporting how the blood-brain barrier functions.*

Is circulation really connected to brain health? 

The research is clear that healthy blood flow is foundational to brain function. The brain consumes roughly 20% of the body’s oxygen despite representing only about 2% of its weight — all delivered through the vascular system. Microcirculation specifically governs that delivery at the cellular level. 

What is Arterosil HP? 

Arterosil HP is a dietary supplement formulated by Calroy Health Sciences to support the structure and normal functions of the endothelial glycocalyx.* It uniquely contains rhamnan sulfate derived from Monostroma nitidum. Its core ingredient, MonitumRS, has been scientifically shown to protect and restore the endothelial glycocalyx.*†

†As demonstrated in an independent third-party laboratory in vitro study.