Aspirin alleviates the symptoms of immunoglobulin A nephropathy via suppressing platelets-mediated non-canonical NF-κB activation in B cells

Abstract

Purpose: Antiplatelet aggregation drugs, such as aspirin, can alleviate pathological renal damage in immunoglobulin A (IgA) nephropathy, although the precise mechanism is unclear.
 Methods: The serum levels of platelet factor 4 (PF4), IgA, and platelet-activating factor (PAF) were assessed by enzyme-linked immunosorbent assay in IgA nephropathy patients and TANK-binding kinase 1 (TBK1)-/- tumor necrosis factor (TNF)-/- mice. The deposition of IgA in glomeruli was detected by immunofluorescence. Phorbol-12-myristate-13-acetate (PMA) induced platelets activation was examined by the cell counting kit 8 assay. B cells were further stimulated with lipopolysaccharides (LPS) or plus platelets supernatant, or combined with nuclear factor kappa-B (NF-κB) inducing kinase (NIK) inhibitor, NIK SMI1.
 Results: Increased serum IgA and proportion of activated platelets were observed in IgA nephropathy patients. TBK1-/-TNF-/- mice had significant increased urinary protein and serum creatinine, and IgA deposition in glomeruli. Up-regulated serum PF4 and PAF were observed in both the IgA nephropathy patients and TBK1-/-TNF-/- mice. Aspirin suppressed the deposition of IgA in glomeruli of TBK1-/-TNF-/- mice with down-regulated platelets activation. Platelets supernatant could promote the proliferation of B cells with up-regulated IgA and sCD40L secretion and up-regulated P52 and RelB expression, which could be inhibited by NIK SMI1 administration.
 Conclusion: TBK1-/-TNF-/- mice demonstrate IgA nephropathy phenotype, which could be alleviated by aspirin administration via inhibiting platelets induced non-canonical NF-κB activation mediated IgA production in B cells.