ABSTRACT
Background@#Ferroptosis, which is caused by an iron-dependent accumulation of lipid hydroperoxides, is a type of cell death linked to diabetic kidney disease (DKD). Previous research has shown that fatty acid binding protein 4 (FABP4) is involved in the regulation of ferroptosis in diabetic retinopathy. The present study was constructed to explore the role of FABP4 in the regulation of ferroptosis in DKD. @*Methods@#We first detected the expression of FABP4 and proteins related to ferroptosis in renal biopsies of patients with DKD. Then, we used a FABP4 inhibitor and small interfering RNA to investigate the role of FABP4 in ferroptosis induced by high glucose in human renal proximal tubular epithelial (HG-HK2) cells. @*Results@#In kidney biopsies of DKD patients, the expression of FABP4 was elevated, whereas carnitine palmitoyltransferase-1A (CP-T1A), glutathione peroxidase 4, ferritin heavy chain, and ferritin light chain showed reduced expression. In HG-HK2 cells, the induction of ferroptosis was accompanied by an increase in FABP4. Inhibition of FABP4 in HG-HK2 cells changed the redox state, sup-pressing the production of reactive oxygen species, ferrous iron (Fe2+), and malondialdehyde, increasing superoxide dismutase, and reversing ferroptosis-associated mitochondrial damage. The inhibition of FABP4 also increased the expression of CPT1A, reversed lipid deposition, and restored impaired fatty acid β-oxidation. In addition, the inhibition of CPT1A could induce ferroptosis in HK2 cells. @*Conclusion@#Our results suggest that FABP4 mediates ferroptosis in HG-HK2 cells by inhibiting fatty acid β-oxidation.
ABSTRACT
Fast optic disk localization and boundary segmentation is an important research topic in computer aided diagnosis. This paper proposes a novel method to effectively segment optic disk by using human visual characteristics in analyzing and processing fundus image. After a general analysis of optic disk features in fundus images, the target of interest could be located quickly, and intensity, color and spatial distribution of the disc are used to generate saliency map based on pixel distance. Then the adaptive threshold is used to segment optic disk. Moreover, to reduce the influence of vascular, a rotary scanning method is devised to achieve complete and continuous contour of optic disk boundary. Tests in the public fundus images database Drishti-GS have good performances, which mean that the proposed method is simple and rapid, and it meets the standard of the eye specialists. It is hoped that the method could be conducive to the computer aided diagnosis of eye diseases in the future.