Functional convergence of Akt protein with VEGFR-1 in human endothelial progenitor cells exposed to sera from patient with type 2 diabetes mellitus

• Published in: Microvascular research Vol. 114; pp. 101 - 113
• Main Authors: Hassanpour, Mehdi, Rezabakhsh, Aysa, Rahbarghazi, Reza, Nourazarian, Alireza, Nouri, Mohammad, Avci, Çığır Biray, Ghaderi, Shahrooz, Alidadyani, Neda, Bagca, Bakiye Goker, Bagheri, Hesam Saghaei
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.11.2017
• Subjects: Adult; Apoptosis; Case-Control Studies; Cell Movement; Cells, Cultured; Diabetes mellitus; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - enzymology; Diabetes Mellitus, Type 2 - genetics; Diabetes Mellitus, Type 2 - pathology; Endothelial Progenitor Cells - enzymology; Endothelial Progenitor Cells - pathology; Gene Expression Regulation; Hedgehog Proteins - metabolism; Human endothelial progenitor cells; Humans; Male; mTOR and Hedgehog signaling pathways; Neovascularization, Physiologic; Proto-Oncogene Proteins c-akt - genetics; Proto-Oncogene Proteins c-akt - metabolism; Receptor Cross-Talk; Receptor tyrosine kinases; Receptor, TIE-1 - metabolism; Receptor, TIE-2 - metabolism; Signal Transduction; Time Factors; TOR Serine-Threonine Kinases - metabolism; Vascular Endothelial Growth Factor Receptor-1 - genetics; Vascular Endothelial Growth Factor Receptor-1 - metabolism; Vascular Endothelial Growth Factor Receptor-2 - metabolism; Human endothelial progenitor cells; Diabetes mellitus; Receptor tyrosine kinases; mTOR and Hedgehog signaling pathways
• ISSN: 0026-2862; 1095-9319; 1095-9319
• DOI: 10.1016/j.mvr.2017.07.002

Diabetes mellitus type 2 predisposes patients to various microvascular complications. In the current experiment, the potent role of diabetes mellitus was investigated on the content of VEGFR-1, -2, Tie-1 and -2, and Akt in human endothelial progenitor cells. The gene expression profile of mTOR and Hedgehog signaling pathways were measured by PCR array. The possible crosstalk between RTKs, mTOR and Hedgehog signaling was also studied by bioinformatic analysis. Endothelial progenitor cells were incubated with serum from normal and diabetic for 7days. Compared to non-treated cells, diabetic serum-induced cell apoptosis (~2-fold) and prohibited cell migration toward bFGF (p<0.001). ELISA analysis showed that diabetes exposed cells had increased abundance of Tie-1, -2 and VEGFR-2 and reduced amount of VEGFR-1 (p<0.0001) in diabetic cells. Western blotting showed a marked reduction in the protein level of Akt after cells exposure to serum from diabetic subjects (p<0.0001). PCR array revealed a significant stimulation of both mTOR and Hedgehog signaling pathways in diabetic cells (p<0.05). According to data from bioinformatic datasets, we showed VEGFR-1, -2 and Tie-2, but not Tie-1, are master regulators of angiogenesis. There is a crosstalk between RTKs and mTOR signaling by involving P62, GABARAPL1, and HTT genes. It seems that physical interaction and co-expression of Akt decreased the level of VEGFR-1 in diabetic cells. Regarding data from the present experiment, diabetic serum contributed to uncontrolled induction of both mTOR and Hedgehog signaling in endothelial progenitor cells. Diabetes mellitus induces mTOR pathway by involving receptor tyrosine kinases while Hedgehog stimulation is independent of these receptors. •Diabetic condition decreased human endothelial progenitor cells viability and migration capacity.•The number of cells entering apoptosis increased in diabetic condition.•The expression of Akt and VEGFR-1 was reduced while the level of VEGFR2, Tie-1, and Tie-2 increased.•This study also demonstrated physical interaction and co-expression of Akt decreased the level of VEGFR-1 in diabetic cells.