Effects of low-level laser on the expression of interleukin-6, tumor necrosis factor‑α, osteoprotegerin, and receptor activator of nuclear factor-κB ligand in human periodontal ligament cells / 华西口腔医学杂志

OBJECTIVES@#This study aims to determine the effects of low-level laser (LLL) on the expression of interleukin-6 (IL-6), tumor necrosis factor (TNF)-α, osteoprotegerin (OPG), and receptor activator of nuclear factor-κB ligand (RANKL) in human periodontal ligament cells (HPDLCs) stimulated by high glucose; and identify the molecular mechanism of LLL therapy in the regulation of periodontal inflammation and bone remodeling during orthodontic treatment in diabetic patients.@*METHODS@#HPDLCs were cultured in vitro to simulate orthodontic after loading and irradiated with LLL therapy. The cultured cells were randomly divided into four groups: low glucose Dulbecco's modification of Eagle's medium (DMEM)+stress stimulation (group A), high glucose DMEM+stress stimulation (group B), hypoglycemic DMEM+LLL therapy+stress stimulation (group C), and hyperglycemic DMEM+LLL therapy+stress stimulation (group D). Groups C and D were further divided into C1 and D1 (energy density: 3.75 J/cm2) and C2 and D2 (energy density: 5.625 J/cm2). Cells in groups A, B, C, and D were irradiated by LLL before irradiation. At 0, 12, 24, 48, and 72 h, the supernatants of the cell cultures were extracted at regular intervals, and the protein expression levels of IL-6, TNF-α, OPG, and RANKL were detected by enzyme-linked immunosorbent assay.@*RESULTS@#1) The levels of IL-6 and TNF-α secreted by HPDLCs increased gradually with time under static pressure stimulation. After 12 h, the levels of IL-6 and TNF-α secreted by HPDLCs in group A were significantly higher than those in groups B, C1, and C2 (P<0.05), which in group B were significantly higher than those in groups D1, and D2 (P<0.01). 2) The OPG protein concentration showed an upward trend before 24 h and a downward trend thereafter. The RANKL protein concentration increased, whereas the OPG/RANKL ratio decreased with time. Significant differen-ces in OPG, RANKL, and OPG/RANKL ratio were found among group A and groups B, C1, C2 as well as group B and groups D1, D2 (P<0.05).@*CONCLUSIONS@#1) In the high glucose+stress stimulation environment, the concentrations of IL-6 and TNF-α secreted by HPDLCs increased with time, the expression of OPG decreased, the expression of RANKL increased, and the ratio of OPG/RANKL decreased. As such, high glucose environment can promote bone resorption. After LLL therapy, the levels of IL-6 and TNF-α decreased, indicating that LLL therapy could antagonize the increase in the levels of inflammatory factors induced by high glucose environment and upregulate the expression of OPG in human HPDLCs, downregulation of RANKL expression in HPDLCs resulted in the upregulation of the ratio of OPG/RANKL and reversed the imbalance of bone metabolism induced by high glucose levels. 2) The decrease in inflammatory factors and the regulation of bone metabolism in HPDLCs were enhanced with increasing laser energy density within 3.75-5.625 J/cm2. Hence, the ability of LLL therapy to modulate bone remodeling increases with increasing dose.

Effects of PEDF on proliferation, apoptosis and invasion of squamous lung carcinoma cells in high-glucose environment / 西安交通大学学报(医学版)

Objective: To study the effects of pigment epithelial-derived factor (PEDF) on the proliferation, apoptosis and invasion of squamous lung carcinoma cells in high-glucose environment so as to explore the significance of PEDF in the development, prognosis and treatment of lung cancer associated with diabetes. Methods: SK-MES-1 lung squamous carcinoma cells were cultured and divided into negative control group; high-glucose group; and PEDF+high glucose groups 1, 2 and 3. The cell morphological changes were observed under the inverted microscope. Then proliferation inhibition rates of SK-MES-1 cells in all the groups were observed by MTT assay. The cell cycle and cell apoptosis rates were detected by flow cytometry. The number of penetration cells was determined by cell invasion experiment. Expression of VEGF in culture supernatant in each group was detected by ELISA. Results: ① Compared with that in the negative control group, the proliferation inhibition rate and apoptosis rate in high-glucose group were low, the percentage of cells blocked in G0/G1 phase was decreased, the number of penetration cells was increased and the concentration of VEGF was increased (P<0.05). ② With the increase of PEDF intervention concentration, the proliferation inhibition rate and apoptosis rate in each group increased, the percentage of G0/G1 phase increased, the number of penetration cells decreased, and the concentration of VEGF decreased (P<0.05). Conclusion: ① The development of squamous cell carcinoma of the lung is promoted in high glucose. ② PEDF can inhibit the proliferation of lung squamous cell carcinoma cells in high-glucose environment, promote early apoptosis and reduce the invasiveness in the concentration-dependent manner. PEDF is predicted to be a target therapeutic drug for lung cancer complicated with diabetes mellitus.

Effects of rosiglitazone on activation of human umbilical vein endothelial cells in high glucose environment / 局解手术学杂志

Objective To investigate the effects of rosiglitazone on proangiogenesis function of human umbilical vein endothelial cells ( HUVEC) in high glucose environment. Methods HUVECs were cultured in high glucose environment and stimulated by rosiglitazone. MTT, cell scratch test and Transwell assay were used to detect HUVEC proliferation and migration. The concentration of VEGF, SDF-1 was also detected in the supernatant. Results Rosiglitazone could effectively promote HUVEC proliferation and migration. The concentration of VEGF and SDF-1 in rosiglitazone stimulated supernatant was higher than that in high glucose group. The inhibition of AKT signal could block the promotion of rosiglitazone on the HUVEC proliferation, migration and secretion. Conclusion Rosiglitazone could significantly promote HUVEC secretion, proliferation and migration in high glucose environment. AKT signal played an important role in this process.