Jere Sandy Winfield, Houreld Nicolette Nadene, Abrahamse Heidi
Laser Research Centre, Faculty of Health Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, South Africa.
Laser Research Centre, Faculty of Health Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, South Africa.
J Photochem Photobiol B. 2018 Feb;179:74-83. doi: 10.1016/j.jphotobiol.2017.12.026. Epub 2018 Jan 4.
Photobiomodulation (PBM) modulates cellular processes to enhance diabetic wound healing. The photon energy activates wounded cells to proliferate and migrate. However, the signalling pathways responsible for these observations remain unknown. This study aimed to determine if PBM stimulates cellular proliferation and migration via the expression of epidermal growth factor (EGF) and activation of the Janus kinase/Signal transducer and activators of transcription (JAK/STAT) signalling pathway. Normal, wounded, diabetic and diabetic wounded cell models were exposed to PBM at a wavelength of 660nm and fluence of 5J/cm and incubated for 48h. Non-irradiated cells (0J/cm) and cells exposed to exogenous EGF (rh EGF) served as controls. Cellular migration was determined microscopically at 0, 24 and 48h. Flow cytometry (BrdU) was used to determine cell proliferation, while the Trypan blue exclusion assay and adenosine triphosphate (ATP) luminescence was used to determine cell viability. The enzyme linked immunosorbent assay (ELISA) was used to analyse EGF expressed in the culture media, and phosphorylated (p-) EGF receptor (p-EGFR), p-JAK2, p-STAT1 and p-STAT5 in cells. Irradiated diabetic wounded cells showed a significant increase in EGF, and activation of its receptor (p-EGFR) and JAK/STAT (p-JAK2, p-STAT1 and p-STAT5). PBM at 660nm and 5J/cm is able to modulate cellular autocrine signalling, particularly the EGF/EGFR loop leading to activation of the JAK/STAT pathway which in turn stimulates cell proliferation and migration.
光生物调节作用（PBM）可调节细胞过程以促进糖尿病伤口愈合。光子能量激活受伤细胞以使其增殖和迁移。然而，导致这些现象的信号通路仍不清楚。本研究旨在确定PBM是否通过表皮生长因子（EGF）的表达和Janus激酶/信号转导子和转录激活子（JAK/STAT）信号通路的激活来刺激细胞增殖和迁移。将正常、受伤、糖尿病和糖尿病受伤细胞模型暴露于波长为660nm、能量密度为5J/cm²的PBM下，并孵育48小时。未照射的细胞（0J/cm²）和暴露于外源性EGF（rh EGF）的细胞作为对照。在0、24和48小时通过显微镜观察确定细胞迁移。使用流式细胞术（BrdU）确定细胞增殖，而使用台盼蓝排斥试验和三磷酸腺苷（ATP）发光法确定细胞活力。酶联免疫吸附测定（ELISA）用于分析培养基中表达的EGF以及细胞中的磷酸化（p-）EGF受体（p-EGFR）、p-JAK2、p-STAT1和p-STAT5。照射后的糖尿病受伤细胞显示EGF显著增加，其受体（p-EGFR）和JAK/STAT（p-JAK2、p-STAT1和p-STAT5）被激活。波长为660nm、能量密度为5J/cm²的PBM能够调节细胞自分泌信号，特别是EGF/EGFR环，导致JAK/STAT通路激活，进而刺激细胞增殖和迁移。
