pH regulates the lumen diameter of tissue-engineered capillaries

Exp Ther Med. 2022 Apr;23(4):284. doi: 10.3892/etm.2022.11212. Epub 2022 Feb 15.

Abstract

Angiogenesis is vital in tissue engineering and the size of the capillary lumen diameter directly affects vascular function. Therefore, the involvement of the pH in the regulation of the capillary lumen diameter was investigated in the present study. The cytosolic pH of different pH medium groups was measured using flow cytometry. Bromodeoxyuridine staining and wound-healing assays were performed to detect cell proliferation and migration, respectively. The expression of angiogenesis-related genes was detected using reverse transcription-quantitative PCR. In addition, cell tube formation under different pH conditions was assessed using a tube formation assay and a 3D Matrigel® model. The results indicated that a change in the pH value of the culture medium affected the cytosolic pH of the endothelial cells, which then led to a change in vascular diameter. When the medium's pH ranged from 7.4 to 7.6, the diameter of the lumen formed in the Matrigel was suitable for capillary formation in tissue engineering. The present results revealed an important role for the pH in the process of capillary formation and provided insight for pH regulation during endothelial cell tube formation and angiogenesis in tissue engineering.

Keywords: angiogenesis; capillary diameter; pH; tissue engineering.

Grants and funding

Funding: This work was supported by grants from the National Natural Science Foundation of China (grant nos. 31570986 and 81701909).