BACKGROUND: Our former studies have shown that bone marrow mesenchymal stem cells (BMMSCs) can be induced differentiation to vascular smooth muscle-like cells (VSMLCs) and vascular endothelium-like cells (VELCs), which are compatible with collagen-embedded polyglycolic acid scaffolds. OBJECTIVE: To investigate the possibility of constructing small diameter tissue-engineered blood vessels via subcutaneous implantation. METHODS: The cells-scaffold complex was produced by separately seeding VSMLCs and VELCs derived from BMMSCs on polyglycolic acid collagen scaffolds. The two layers were separated by ECMgel. The cells-scaffold complex was subcutaneous implanted into small diameter tissue-engineered blood vessels.RESULTS AND CONCLUSION: Histological analysis of the small diameter tissue-engineered blood vessel walls revealed a typical artery structure, which was similar to natural vessels. The tissue-engineered blood vessels were not broken down under a force of 26.6 kPa. Eight weeks after implantation, the Brdu-labeled seed cells were found in the three layers of the vessel walls. The results revealed that the subcutaneous tissue was a good bioreactor to construct small diameter tissue-engineered blood vessels.

VEGF nanoparticle (VEGF-NP) was prepared by a multi-emulsification technique using a biodegradable poly-dl-lactic-co-glycolic (PLGA) as matrix material. The nanoparticles were characterized for size, VEGF loading capacity, and in vitro release. VEGF-NP and naked VEGF plasmid were intramuscularly injected into the ischemia site of the rabbit chronic hindlimb ischemia model and the efficiency of VEGF-NP as gene delivery carrier for gene therapy in animal model was evaluated. Gene therapuetic effect was assessed evaluated by RT-PCR, immunohistochemistry and angiography assay. The average size of VEGF-NP was around 300 nm. The encapsulation efficiency of VEGF was above 96%. Loading amount of VEGF in the nanoparticles was about 4%. In vitro, nanoparticles maintained sustained-release of VEGF for two weeks. Two weeks post gene injection the capillary density in VEGF-NP group (81.22 per mm2) was significantly higher than that in control group (29.54 mm2). RT-PCR results showed greatly higher VEGF expression in VEGF-NP group (31.79au * mm) than that in naked VEGF group (9.15 au * mm). As a carrier system for gene therapy in animal model, VEGF-NP is much better than naked DNA plasmid. The results demonstrate great possibility of using NP carrier in human gene therapy.
Animals ; Disease Models, Animal ; Gene Transfer Techniques ; Genetic Therapy ; Genetic Vectors ; chemistry ; Lactic Acid ; chemistry ; Nanoparticles ; chemistry ; Plasmids ; Polyglycolic Acid ; chemistry ; Rabbits ; Vascular Endothelial Growth Factor A ; genetics

More and more studies have found that diabetes is closely related to white matter hyperintensities. This article reviews the relationship between diabetes and white matter hyperintensities, the effect of white matter hyperintensities on cognitive impairment in patients with diabetes, and the relationship between the two and stroke.

Homocysteine participates in the methionine cycle in the body and is excreted by the kidneys. Its abnormal elevation increases the risk of cerebrovascular disease. Studies in recent years have shown that hyperhomocysteinemia is closely related to cerebral small vessel diseases and is an independent risk factor for ischemic stroke and cognitive impairment. Because hyperhomocysteinemia is largely reversible, the significance of drug intervention in the prevention and treatment of cerebrovascular disease has gradually been confirmed. This article reviews the relationship between homocysteine and cerebral small vessel diseases in order to provide a reference for the prevention of stroke and dementia.