Hydroxytyrosol contributes to cell proliferation and inhibits apoptosis in pulsed electromagnetic fields treated human umbilical vein endothelial cells in vitro

Abstract

A variety of pulsed electromagnetic fields (PEMFs) have been experimentally and clinically used in an effort to promote wound healing, although the mechanisms involved remain unknown. The aim of the present study was to investigate the action of a novel protocol of co-treatment with PEMFs and hydroxytyrosol (HTY) on the proliferation and differentiation potential of human umbilical vein endothelial cells (HUVECs). The HUVECs were assigned randomly into three groups: Control, PEMF-treated and PEMF + HT-treated. The intensity of the electromagnetic field used in this protocol was 2.25 mT, the frequency of the bursts was 50 Hz and the application time was 15 min. A Cell Counting kit-8 (CCK-8) assay was used to assess cell proliferation, and cell apoptosis was analyzed by TUNEL apoptosis assay kit and calcein-acetoxymethyl/propidium iodide dual-staining assay. In addition, protein and mRNA expression levels of protein kinase B (Akt), mechanistic target of rapamycin (mTOR), transforming growth factor (TGF)-β1 and p53 were determined by western blotting and reverse transcription-quantitative polymerase chain reaction assays, respectively. The CCK-8 assay demonstrated that HTY contributed to HUVEC proliferation mediated by PEMFs in a time-dependent manner. The Transwell assay and scratch wound results demonstrated that co-treatment of HTY and PEMFs could increase HUVEC migration. Furthermore, the levels of apoptotic cells were reversed by pre-incubation with HTY in the PEMF treatment group, while PEMF treatment alone had no such effect. The proteins and mRNA expression levels of Akt, mTOR, TGF-β1 were elevated in co-treatment of HTY and PEMFs, whereas there was no effect on levels of p53. Therefore, the results indicated that combined exposure of HUVECs to PEMFs and HTY exerted protective effects in HUVECs by promoting cell proliferation and inhibiting apoptosis. In conclusion, to the best of our knowledge, the present study was the first to demonstrate the beneficial roles of HTY and PEMF combined treatment in HUVECs, which may represent an effective treatment for wound healing.

Hydroxytyrosol stimulates neurogenesis in aged dentate gyrus by enhancing stem and progenitor cell proliferation and neuron survival

“…75 However, in normal cells HTyr exhibits pro-proliferative activity, as, for example, observed in human osteoblasts, 76 or in endothelial cells, where AKT, mTOR, and Tgf-beta levels were increased. 77 This further suggests that the proliferative stimulation by HTyr that we observed in dentate gyrus cells, either aged or lacking the inhibitory regulation of cell cycle by Btg1, but not in adult cells, is dependent on the cellular condition.…”

Molecular Action of Hydroxytyrosol in Wound Healing: An In Vitro Evidence-Based Review

“…All studies were published within the year 2010 until 2020. Three studies reported the antiangiogenic effect of HT [ 32 , 33 , 34 ], while another three studies reported its proangiogenic effect [ 35 , 36 , 37 ]. Three studies examined the antioxidant effect of HT [ 38 , 39 , 40 ].…”

“…Three studies focused on investigating the antimicrobial effect of HT [ 42 , 43 , 44 ]. Moreover, eight studies also included the anti-inflammatory effect of HT as a supplementary outcome of their studies [ 32 , 33 , 34 , 35 , 38 , 39 , 40 , 41 ].…”

“…Formation of new vasculature network within the injured tissue is crucial in supporting its restoration back to its functional state. Thus, the angiogenic property of hydroxytyrosol has become a subject of interest to 6 out of the 13 studies included [ 32 , 33 , 34 , 35 , 36 , 37 ]. Contradicting results were reported whereby three studies reported antiangiogenic properties with HT, while the remaining three studies reported proangiogenic properties of HT.…”

“…Indeed, PEMF alone demonstrated enhancement of HUVEC proliferation and migration. HT addition enhances these effects on HUVEC [ 35 ].…”