Sutong Li1, Xiaoxia Liu2, Jie Lei1, Junle Yang3, Puxun Tian4, Yi Gao1. 1. Department of Nephropathy, Xi'an, China. 2. Department of Endocrinology, Xi'an, China. 3. Department of Radiology, Xi'an Central Hospital, Xi'an, China. 4. Department of Renal Transplantation, Kidney Disease Hospital of the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
Abstract
BACKGROUND/AIMS: Diabetic nephropathy (DN) is a microangiopathic disease characterized by excessive urinary albumin excretion, which occurs in 30% of patients with diabetes mellitus. It is the second leading cause of end-stage renal diseases in China. Nuclear factor-kappa B (NF-κB) is reported to be closely correlated with the inflammation underlying diabetes-associated renal damage. Crocin, a plant-derived compound, has antioxidant properties that may inhibit NF-κB. METHODS: In the present study, we used a conditionally immortalized mouse podocyte cell line to explore whether crocin could effectively block albuminuria. Cells were incubated with 15 or 25 mM D-glucose to mimic diabetic conditions. The expression of Wilms tumor 1 (WT-1) and synaptopodin was evaluated to identify differentiated podocytes, and the expression of nephrin, podocin, and CD2ap was measured as markers of slit diaphragms, the main structures within the glomerular filtration barrier. RESULTS: The high-glucose conditions led to reduced nephrin, podocin, and CD2ap expression, which was prevented by pretreatment with crocin. The oxidative stress and pro-inflammatory response of podocytes associated with DN induced by high glucose were also reduced by crocin pretreatment. Phosphorylated IκBα (p-IκBα) expression induced by high glucose was also significantly decreased by crocin pretreatment. Moreover, pyrrolidine dithiocarbamate, a NF-κB inhibitor, pyrrolidine dithio carbamate, augmented the protective effects of crocin. CONCLUSION: Our results demonstrate a protective role of crocin against damage to podocytes and slit diaphragms under high-glucose conditions via inhibition of NF-κB. This study presents a potential therapy for DN and contributes to the understanding of the mechanism underlying DN.
BACKGROUND/AIMS: Diabetic nephropathy (DN) is a microangiopathic disease characterized by excessive urinary albumin excretion, which occurs in 30% of patients with diabetes mellitus. It is the second leading cause of end-stage renal diseases in China. Nuclear factor-kappa B (NF-κB) is reported to be closely correlated with the inflammation underlying diabetes-associated renal damage. Crocin, a plant-derived compound, has antioxidant properties that may inhibit NF-κB. METHODS: In the present study, we used a conditionally immortalized mouse podocyte cell line to explore whether crocin could effectively block albuminuria. Cells were incubated with 15 or 25 mM D-glucose to mimic diabetic conditions. The expression of Wilms tumor 1 (WT-1) and synaptopodin was evaluated to identify differentiated podocytes, and the expression of nephrin, podocin, and CD2ap was measured as markers of slit diaphragms, the main structures within the glomerular filtration barrier. RESULTS: The high-glucose conditions led to reduced nephrin, podocin, and CD2ap expression, which was prevented by pretreatment with crocin. The oxidative stress and pro-inflammatory response of podocytes associated with DN induced by high glucose were also reduced by crocin pretreatment. Phosphorylated IκBα (p-IκBα) expression induced by high glucose was also significantly decreased by crocin pretreatment. Moreover, pyrrolidine dithiocarbamate, a NF-κB inhibitor, pyrrolidine dithio carbamate, augmented the protective effects of crocin. CONCLUSION: Our results demonstrate a protective role of crocin against damage to podocytes and slit diaphragms under high-glucose conditions via inhibition of NF-κB. This study presents a potential therapy for DN and contributes to the understanding of the mechanism underlying DN.
Authors: Stefania Vitale; Sara Colanero; Martina Placidi; Giovanna Di Emidio; Carla Tatone; Fernanda Amicarelli; Anna Maria D'Alessandro Journal: Molecules Date: 2022-06-01 Impact factor: 4.927