CD36 Promotes Podocyte Apoptosis by Activating the Pyrin Domain-Containing-3 (NLRP3) Inflammasome in Primary Nephrotic Syndrome
Xuejun Yang, You Wu, Qianqian Li, Gaofu Zhang, Mo Wang, Haiping Yang, Qiu Li
(Key Laboratory of the Ministry of Education, Key Laboratory of Pediatrics in Chongqing, Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, and Chongqing Key Laboratory of Child Infections and Immunity, Chongqing, China (mainland))
Med Sci Monit 2018; 24:6832-6839
CD36 plays a critical role in many sterile inflammatory diseases, including type 2 diabetes mellitus, atherosclerosis, and primary nephrotic syndrome. This study investigated whether CD36 activates the nucleotide-binding domain leucine-rich repeat-containing family, pyrin domain-containing-3 (NLRP3) inflammasome and promotes podocytes apoptosis in primary nephrotic syndrome.
MATERIAL AND METHODS: The mouse podocyte cell line MPC5 was used as a model. mRNA and protein expression of CD36 and NLRP3 was quantified by real-time PCR and Western blotting, respectively. Levels of caspase-1 activity and total cholesterol were determined using commercial kits. Intracellular lipid droplets were detected by Oil Red O staining. CD36 expression was also examined in nephrotic mouse kidney tissue by immunohistochemistry and immunofluorescence. Intracellular lipid droplet was examined by Oil Red O staining.
RESULTS: CD36 expression was increased in nephrotic mouse kidney tissue. Treatment with interleukin-1b increased expression of CD36 and total cholesterol in MPC5 cells. Moreover, this treatment increased expression of NLRP3 and the percentage of apoptotic cells, both of which were inhibited by co-treatment with an anti-CD36 antibody.
CONCLUSIONS: CD36 might play an important role in podocyte apoptosis by activating the NLRP3 inflammasome in primary nephrotic syndrome.
Keywords: Antigens, CD36, Inflammasomes, Inflammation, nephrotic syndrome, Podocytes