Air Force Military Medical University develops new strategy to improve blood vessel transplantation in aging individuals

In recent years, with the prevalence of cardiovascular diseases, people's demand for vascular grafts has been increasing

Recently, a research team from the Air Force Military Medical University clarified the role of autophagy in macrophage polarization and its effect on vascular remodeling in aging individuals

Polyglyceryl sebacate-polycaprolactone (PGS-PCL) vascular graft is a new type of synthetic graft that can be transformed into a vascular-like structure in situ using the host's own regeneration ability

The idea of ​​this research is to incorporate autophagy targeting drugs (rapamycin and 3-MA) ​​into the PCL sheath of the graft based on the PGS-sodium citrate stent to prepare an immunomodulated vascular graft , And analyze macrophage infiltration and autophagy

Aging leads to reduced autophagy in macrophages

In order to evaluate the adverse effects of aging on vascular remodeling, the researchers first implanted PGS-PCL grafts into the abdominal aorta of 15 aged rats and 15 young rats

Considering that autophagy is closely related to aging, the researchers then began to evaluate the level of autophagy in macrophages

Some recent evidence suggests that autophagy can regulate the polarization of macrophages under different inflammatory conditions

Autophagy can regulate macrophage polarization and biomaterial degradation

The PGS-PCL graft used in this study consists of a PGS-salt stent and an ultra-thin PCL sheath wrapped on the outside

In order to detect the autophagy flux in the cells that migrated into the vascular graft, they immunostained multiple markers such as the autophagy marker LC3 two weeks after transplantation

So, what effect does macrophage autophagy have on the degradation of materials in the body? They analyzed the new arteries generated by the grafts loaded with PBS, rapamycin, and 3-MA two weeks and six months after implantation

Next, the researchers analyzed the effect of regulating the autophagy of macrophages on the polarization of macrophages

In addition, the rapamycin in the PGS-PCL graft enhanced the recruitment of myoblasts after two weeks and promoted their differentiation into smooth muscle cells within six months

Concluding remarks

The researchers stated that they successfully improved the vascular regeneration in aging individuals by manipulating the autophagy of macrophages, and confirmed the role of autophagy in graft degradation and macrophage polarization

Original Search

Wanli Chen, Weiwei Xiao, Xuzheng Liu, Pingping Yuan, Siqian Zhang, Yinggang Wang, Wei Wu.
Pharmacological manipulation of macrophage autophagy effectively rejuvenates the regenerative potential of biodegrading vascular graft in aging body.
Bioactive Materials, 2021.
https://doi.
org/10.
1016/j.
bioactmat.
2021.
09.
027 .