Arg-Gly-Asp-modified elastin-like polypeptide regulates cell proliferation and cell cycle proteins via the phosphorylation of Erk and Akt in pancreatic β-cell

Yeo Jin Hwang; Gwon-Soo Jung; Won Bae Jeon; Kyeong-Min Lee

doi:10.1016/j.heliyon.2020.e04918

Arg-Gly-Asp-modified elastin-like polypeptide regulates cell proliferation and cell cycle proteins via the phosphorylation of Erk and Akt in pancreatic β-cell

Heliyon. 2020 Sep 14;6(9):e04918. doi: 10.1016/j.heliyon.2020.e04918. eCollection 2020 Sep.

Authors

Yeo Jin Hwang¹, Gwon-Soo Jung², Won Bae Jeon³, Kyeong-Min Lee³

Affiliations

¹ Division of Electronics & Information System, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea.
² New Drug Development Center, Daegu-Gyeongbuk Medical Innovation Foundation, Daegu, Republic of Korea.
³ Division of Biotechnology, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea.

Abstract

Objective: Enhancement of β-cell proliferation plays an important role in maintaining β-cell mass and function, and in improving pancreatic β-cell survival before transplantation. Extracellular matrix (ECM) components increase the adhesion and proliferation of β-cells, and the RGD-modified elastin-like polypeptide (RGD-ELP, REP) has been described as a bioactive matrix. In this study, we investigated whether REP could enhance β-cell adhesion and proliferation and elucidated the signaling pathways involved.

Methods: We investigated the effect of REP on cell adhesion, proliferation and insulin secretion via assays using Rin-m and rat islets. Crystal violet, CCK-8, and BrdU assay, FACS, western blot, real time q-PCR analyses and insulin ELISA were examined. To explain the associated mechanisms, phosphorylation of Akt and extracellular signal-regulated kinase (Erk) were measured.

Results: REP more increased the adhesion, proliferation and survival of Rin-m cells compared to elastin-like poly peptide (ELP) without RGD-motif. The enhancement of β-cell proliferation by REP was associated with increased cyclin D1, cyclin D2 and cdk6, and decreased p27 levels. When β-cells were cultured on REP, Erk and the phosphatidylinositol 3-kinase (PI3-kinase) downstream effector, Akt was stimulated. Treatment with the Erk pathway inhibitor and PI3-kinase inhibitor decreased REP-induced β-cell adhesion and proliferation, and regulated REP-induced cell cycle proteins. Additionally, REP increased the mRNA and protein levels of insulin and its transcription factor, PDX-1, and insulin secretion.

Conclusions: Our results demonstrate that the up-regulation of the PI3K/Akt and Erk signaling pathways and the regulation of cell cycle proteins by REP could serve as effective strategies for improving pancreatic β-cell adhesion and proliferation.

Keywords: Biomedical materials; Biotechnology; Cell biology; Cell cycle; Diabetes; Insulin; RGD-modified elastin-like polypeptide; Tissue engineering; β-cell adhesion; β-cell proliferation.