Fig. 3

CNPs significantly inhibited HK-2 organelle damage and cell cycle arrest induced by high oxalate. A Detection of intracellular reactive oxygen species (ROS); B quantitative analysis results of the ROS in different groups. C, D Mitochondrial membrane potential in HK-2 cells and its fluorescence semi-quantification assay; E TEM observation of the HK-2 cells in different groups. F, G Flow cytometry detection of HK-2 cells’ cycle and quantitative percentage; Protection of HK-2 cells exposed to oxalate by 12.5 µg/mL of CNPs for 24 h, HK-2 cells were observed by TEM, the red arrows indicate mitochondria, yellow arrows indicate autophagic vacuoles, autophagosomes and autolysosomes. The black arrows indicate the distended microvilli. Oxalic acid damage concentration: 1 mM; oxalate damage time: 24 h; CNPs protection time: 24 h; CNPs concentration: 3.125, 6.25, 12.5 µg/mL. Magnification is ×100, Scale bar = 200 μm; ** indicates P < 0.01, *** indicates P < 0.001, **** indicates P < 0.0001, ns indicates P > 0.05, no significant difference