ABSTRACT
Application of fiberoptic endoscopic evaluation of swallowing (FEES) can accurately evaluate the static and dynamic anatomical structure of pharynx and larynx, the feeling of pharynx and larynx, secretion level, aspiration, residue and other important swallowing evaluation indexes, which is important for swallowing treatment and valuable for diagnosis of dysphagia.
ABSTRACT
Objective N-acety-L-cysteine (NAC) can attenuate the injury of podocytes and renal tubular epithelial HK-2 cells induced by contrast agents, but its specific action mechanisms needs to be further clarified. In this study, we investigated the effects of NAC on iopromide (IPM)-induced injury and the NF-κB/NLRP3 signaling pathway in HK-2 cells. Methods Renal tubular epithelial HK-2 cells were divided into seven groups, control, IPM, and IPM + NAC at 2, 4, 8, 16 and 32 mmol/L. After a 24-hour treatment of the HK-2 cells with NAC, CCK-8, DAPI staining, DCFH-DA and Western blot were employed for determination of the viability, apoptosis and morphology of the cells as well as the level of reactive oxygen species (ROS) and the expressions of Bax, Bcl-2, NLRP3, ASC, Caspase-1, IL-1β and NF-κB in the cells. Results Compared with the control, the cells of the IPM group showed a significantly reduced viability ([100 ± 4.749]% vs [48.819 ± 2.045]%, P < 0.05), increased apoptosis, elevated ROS level, and up-regulated expressions of Bax, Bcl-2, NLRP3, ASC, Caspase-1, IL-1β and NF-κB. In comparison with the IPM group, the HK-2 cells treated with NAC at 2, 4, 8, 16 and 32 mmol/L exhibited a remarkably increased viability ([55.398 ± 3.609]%, [58.953 ± 2.859]%, [61.531 ± 5.179]%, [59.845 ± 6.365]% and [59.094 ± 6.285]%) and decreased ROS level and expressions of Bax, Bcl-2, NLRP3, ASC, Caspase-1, IL-1β and NF-κB. The mean fluorescence intensity was significantly higher in the HK-2 cells of the IPM group than in the control cells (5050.85 ± 606.76 vs 1502.17 ± 55.91, P < 0.05), but remarkably decreased in those treated with NAC at 2, 4, 8, 16 and 32 mmol/L (4065.39 ± 106.59, 4162.05 ± 28.93, 3675.71 ± 50.38, 3133.79 ± 66.07 and 2675.80 ± 92.39) (P < 0.05). Conclusion NAC can effectively improve IPM-induced injury of renal tubular epithelial cells, which may be associated with its abilities of inhibiting ROS production and activating the NF-κB/NLRP3 signaling pathway.
ABSTRACT
ObjectiveIopromide can induce injury to HK-2 cells, but its exact mechanism remains poorly understood. This study aimed to explore the influence of iopromide on ROS-NLRP3 inflammasome signaling in HK-2 cells.MethodsHK-2 human renal tubular epithelial cells were divided into six groups: control and iopromide at 37, 74, 111, 148 and 185 mgI/mL. The HK-2 cells in the latter five groups were treated with different concentrations of iopromide for 24 hours. Then the ROS level in the cells was detected by 2′,7′-Dichlorodihydrofluorescein diacetate staining and flow cytometry and the protein expressions of NLRP3, ASC, caspase-1, IL-1β, NF-κB and TNF-α determined by Western blot.ResultsThe ROS level was significantly increased in the HK-2 cells treated with iopromide at 37 mgI/ml (4103.89±98.89), 74 mgI/mL (4450.12±108.90), 111 mgI/mL (5050.85±606.76), 148 mgI/mL (6210.57±145.74) and 185 mgI/ml (7105.13±426.63) as compared with that in the control group (2551.71±84.00) (P<0.05). Western blot showed markedly upregulated expressions of NLRP3, ASC, caspase-1, IL-1β and TNF-α in the HK-2 cells in all the latter five groups in comparison with the control (P<0.05) and an increased level of NF-κB after treated with iopromide at ≥111 mgI/ml (P<0.05).ConclusionIopromide may induce injury to HK-2 cells by activating the ROS-NLRP3 inflammasome signaling pathway.
ABSTRACT
Objective Methylglyoxal can cause the injury of human proximal tubular epithelial cell line(HK-2 cells),but the exact mechanism is still unclear. The present study aimed to explore the influence of oxidative stress and the expression of NLRP3 inflammasome in HK-2 cells induced by methylglyoxal. Methods HK-2 cells at logarithmic phase were divided into six groups:control group and 100,200,400,800,1600 μmol/L methylglyoxal groups (cells were cultured in 100,200,400,800,1600 μmol/L methylg-lyoxal concentration for 24 h). Superoxide dismutase(SOD)levels were assayed by thibabituric acid method. Release of lactate dehydro-genase(LDH)activity was detected by assay kit.ROS production was measured by DCFH-DA staining. The expression levels of NLRP3,caspase-1,IL-1β and NF-κB were evaluated by western blot. Results Compared with control group,different methylglyoxal concen-trations could enhance ROS level and LDH activity in HK-2 cells(P<0.05)and reduce SOD level significantly(P<0.05). The results of western blot showed the protein levels of NLRP3,caspase-1,IL-1β and NF-κB were significant up-regulated after the addition of methylglyoxal(P<0.05). Conclusion Methylglyoxal may induce the injury of HK-2 cells by oxidant stress and activating of NLRP3 inflammasome signaling.