Metformin Reduces Vascular Assembly in High Glucose-Treated Human Microvascular Endothelial Cells in An AMPK-Independent Manner

(Pages: 174-183)
Carolina Silva, Ph.D, 1,2Ilda Rodrigues, M.Sc, 1Sara Andrade, Ph.D, 1,2,3Raquel Costa, Ph.D, 1,2Raquel Soares, Ph.D., 1,2,*
Department of Biomedicine, Unit of Biochemistry, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal
i3S, Institute of Research and Innovation in Health, University of Porto, Porto, Portugal
IPATIMUP, Institute of Pathology and Molecular Immunology, University of Porto, Porto, Portugal
Department of Biomedicine, Unit of Biochemistry, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal
i3S, Institute of Research and Innovation in Health, University of Porto, Porto, Portugal
IPATIMUP, Institute of Pathology and Molecular Immunology, University of Porto, Porto, Portugal
*Corresponding Address: Department of Biomedicine Unit of Biochemistry Faculty of Medicine University of Porto Al Prof Hernâni Monteiro 4200-319 Porto Portugal Email:raqsoa@med.up.pt
The Cell Journal (Yakhteh) is an open access journal which means the articles are freely available online for any individual author to download and use the providing address. The journal is licensed under a Creative Commons Attribution-Non Commercial 3.0 Unported License which allows the author(s) to hold the copyright without restrictions that is permitting unrestricted use, distribution, and reproduction in any medium provided the original work is properly cited. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Silva Carolina, Rodrigues Ilda, Andrade Sara, Costa Raquel, Soares Raquel. Metformin Reduces Vascular Assembly in High Glucose-Treated Human Microvascular Endothelial Cells in An AMPK-Independent Manner. Cell J. 2021; 23(2): 174-183.

Abstract

Objective

The aim is to examine the effect of metformin in human microvascular endothelial cells exposed to high glucose (HG) concentration and compare them with the effects of other 5' adenosine monophosphate-activated protein kinase (AMPK) modulators under the same condition.

Materials and Methods

In this experimental study, human microvascular endothelial cells (HMECs) were treated with 15 mM metformin, 1 mM 5-aminoimidazol-4-carboxamideribonucleotide (AICAR) and 10 mM compound C in the presence of 20 mM glucose (hyperglycemic condition). Migration, invasion and proliferation were evaluated as well as the capillary-like structures formation. Moreover, the expression of angiogenic genes was assessed.

Results

Metformin significantly inhibited vessel formation and migration, although it did not change HMECs proliferation and invasion. In addition, metformin significantly reduced collagen formation as evidenced by histological staining. Concomitantly, expression of several genes implicated in angiogenesis and fibrosis, namely TGFß2, VEGFR2, ALK1, JAG1, TIMP2, SMAD5, SMAD6 and SMAD7, was slightly upregulated. Immunostaining for proteins involved in ALK5 receptor signaling, the alternative TGFß signaling pathway, revealed significant differences in SMAD2/3 expression.

Conclusion

Our data showed that metformin prevents vessel assembly in HMECs, probably through an AMPK- independent mechanism. Understanding the molecular mechanisms by which this pharmacological agent affects endothelial dysfunction is of paramount importance and paves the way to its particular use in preventing development of diabetic retinopathy and nephropathy, two processes where angiogenesis is exacerbated.