Angiogenesis is the ability to form new blood vessels, and diabetes not only damages existing blood vessels, but hinders this innate ability, these experts from the Center for Vascular Biology remind. Their study reveals that 1 session of moderate-intensity exercise of 45 minutes allows more exosomes, microscopic vesicles filled with active biological substances, to directly deliver to endothelial cells more of a protein, ATP7A, which triggers the angiogenesis. Endothelial cells line our blood vessels and are essential for the growth of these new blood vessels.
Exercise stimulates vascular growth
The study, conducted in vitro, in vivo, and on a small group of diabetic patients, by Drs Tohru Fukai and Masuko Ushio-Fukai, vascular biologists and cardiologists is centered on exosomes. The authors point out that what these microscopic vesicles carry depends on where they come from and where they go. Some exosomes deliver specific cargo to endothelial cells. The team shows:
- that ATP7A levels are reduced in diabetes. Exosomes circulating in the plasma of type 2 diabetes models actually alter angiogenesis;
- both in an animal model of diabetes mellitus who practiced running on a wheel for 2 weeks and in a small group of participants in their fifties who did a cardio session, that these exercise sessions increased the levels of the protein ATP7A in exosomes that “deliver” to endothelial cells;
- physical exercise causes muscles to contract, which in turn causes the release of exosomes into the blood;
- if this activity did not have a significant impact on the weight of the mice, it was enough to increase a marker of endothelial function and factors such as the vascular endothelial growth factor necessary for angiogenesis;
- exercise also increased levels of a natural antioxidant, extracellular superoxide dismutase or SOD3, while ATP7A is also known to deliver the essential mineral copper to cells, essential for making good use of this antioxidant…
SOD3 a key natural antioxidant for the vascular system: SOD3 is produced by vascular smooth muscle cells in the walls of blood vessels as well as skeletal muscle cells and helps us maintain healthy levels of reactive oxygen species, or ROS. ROS are a natural byproduct of our use of oxygen which is an important cellular signal, enabling a variety of functions. However, in diabetes, high levels of blood sugar lead to high levels of ROS, which reduces or inhibits important basic functions.
Synthetic exosomes that mimic exercise? This is the avenue opened up by these scientists, aiming with such exosomes where SOD3 is overexpressed, to improve the ability of patients to develop new blood vessels when diabetes has damaged their innate capacity. The exosomes are more generally a much-studied avenue, as biomarkers for a wide range of diseases such as cancer and diabetes,
as well as as specific tools for delivering treatments.