Dexamethasone prodrug treatment prevents nephritis in lupus-prone (NZB × NZW)F1 mice without causing systemic side effects.

OBJECTIVE To evaluate the potentially improved therapeutic efficacy and safety of nephrotropic macromolecular prodrugs of glucocorticoids (GCs) for the treatment of lupus nephritis. METHODS Lupus-prone female (NZB × NZW)F1 mice received monthly injections of N-(2-hydroxypropyl) methacrylamide copolymer-based dexamethasone prodrug (P-Dex) or daily injections of dexamethasone phosphate sodium (Dex; overall dose equivalent to that of P-Dex) for 2 months. During treatment, the mice were monitored for albuminuria, mean arterial pressure, and serum autoantibody levels. Nephritis, renal immune complex levels, and macrophage infiltration were evaluated histologically. Bone quality was analyzed using peripheral dual x-ray absorptiometry and micro-computed tomography. The in vivo distribution of P-Dex was investigated using optical imaging, immunohistochemistry, and fluorescence-activated cell sorting (FACS). The antiinflammatory effect of P-Dex was validated using lipopolysaccharide-activated human proximal tubule epithelial (HK-2) cells. RESULTS Monthly P-Dex injections completely abolished albuminuria in the (NZB × NZW)F1 mice; this approach was significantly more efficacious than daily Dex treatment. P-Dex treatment did not reduce serum levels of anti-double-stranded DNA antibodies or renal immune complexes but did decrease macrophage infiltration, which is a marker of chronic inflammation. Immunohistochemical and FACS analyses revealed that P-Dex was primarily sequestered by proximal tubule epithelial cells, and that it could attenuate the inflammatory response in HK-2 cell culture. In contrast to Dex treatment, P-Dex treatment did not lead to any significant deterioration of bone quality or reduction in the level of total serum IgG. CONCLUSION Macromolecularization of GCs renders them nephrotropic. Protracted retention, subcellular processing, and activation of GC prodrugs by kidney cells would potentiate nephritis resolution, with a reduced risk of systemic toxicities.

[1]  S. Goldring,et al.  Early detection and treatment of wear particle-induced inflammation and bone loss in a mouse calvarial osteolysis model using HPMA copolymer conjugates. , 2011, Molecular pharmaceutics.

[2]  K. Kyriacou,et al.  Podocyte main slit diaphragm proteins, nephrin and podocin, are affected at early stages of lupus nephritis and correlate with disease histology , 2011, Lupus.

[3]  B. Hahn Targeted therapies in systemic lupus erythematosus: successes, failures and future , 2011, Annals of the rheumatic diseases.

[4]  S. Goldring,et al.  Development of a macromolecular prodrug for the treatment of inflammatory arthritis: mechanisms involved in arthrotropism and sustained therapeutic efficacy , 2010, Arthritis research & therapy.

[5]  Y. Alnouti,et al.  Pharmacokinetic and biodistribution studies of N-(2-hydroxypropyl)methacrylamide copolymer-dexamethasone conjugates in adjuvant-induced arthritis rat model. , 2010, Molecular pharmaceutics.

[6]  D. Cullen,et al.  Effects of glucocorticoid treatment on bone strength , 2010, Journal of Bone and Mineral Metabolism.

[7]  Xun Sun,et al.  Specific renal uptake of randomly 50% N-acetylated low molecular weight chitosan. , 2009, Molecular pharmaceutics.

[8]  K. Fu,et al.  Synthesis and Evaluation of a Well-defined HPMA Copolymer–Dexamethasone Conjugate for Effective Treatment of Rheumatoid Arthritis , 2008, Pharmaceutical Research.

[9]  G. Ferraccioli,et al.  Renal interstitial cells, proteinuria and progression of lupus nephritis: new frontiers for old factors , 2008, Lupus.

[10]  T. Kielian,et al.  The Synthetic Peroxisome Proliferator-Activated Receptor-γ Agonist Ciglitazone Attenuates Neuroinflammation and Accelerates Encapsulation in Bacterial Brain Abscesses1 , 2008, The Journal of Immunology.

[11]  M. Bawendi,et al.  Renal clearance of quantum dots , 2007, Nature Biotechnology.

[12]  G. Remuzzi,et al.  Involvement of renal tubular Toll-like receptor 9 in the development of tubulointerstitial injury in systemic lupus. , 2007, Arthritis and rheumatism.

[13]  S. Goldring,et al.  Novel dexamethasone-HPMA copolymer conjugate and its potential application in treatment of rheumatoid arthritis , 2007, Arthritis research & therapy.

[14]  Hong Ding,et al.  Randomly 50% N-acetylated low molecular weight chitosan as a novel renal targeting carrier , 2007, Journal of drug targeting.

[15]  T. Chan,et al.  Effect of human anti-DNA antibodies on proximal renal tubular epithelial cell cytokine expression: implications on tubulointerstitial inflammation in lupus nephritis. , 2005, Journal of the American Society of Nephrology : JASN.

[16]  L. Allegri,et al.  Early Proinflammatory Activation of Renal Tubular Cells by Normal and Pathologic IgG , 2005, Nephron Experimental Nephrology.

[17]  Y. Yoshioka,et al.  The targeting of anionized polyvinylpyrrolidone to the renal system. , 2004, Biomaterials.

[18]  Y. Yoshioka,et al.  Synthesis of a poly(vinylpyrrolidone-co-dimethyl maleic anhydride) co-polymer and its application for renal drug targeting , 2003, Nature Biotechnology.

[19]  J. Lai,et al.  Functional Polymers from Novel Carboxyl-Terminated Trithiocarbonates as Highly Efficient RAFT Agents , 2002 .

[20]  V. M. Holers,et al.  Complement is activated in kidney by endotoxin but does not cause the ensuing acute renal failure. , 2000, Kidney international.

[21]  J. Kopeček,et al.  Targetable HPMA copolymer-adriamycin conjugates. Recognition, internalization, and subcellular fate. , 1998, Journal of controlled release : official journal of the Controlled Release Society.

[22]  S. Shak,et al.  The treatment of systemic lupus erythematosus (SLE) in NZB/W F1 hybrid mice; studies with recombinant murine DNase and with dexamethasone , 1996, Clinical and experimental immunology.

[23]  M. Daha,et al.  Interleukin 6 production by human proximal tubular epithelial cells in vitro: analysis of the effects of interleukin-1α (IL-1α) and other cytokines , 1994 .

[24]  M. Daha,et al.  Interleukin 6 production by human proximal tubular epithelial cells in vitro: analysis of the effects of interleukin-1 alpha (IL-1 alpha) and other cytokines. , 1994, Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association.

[25]  T. Sugisaki,et al.  Composition of immune deposits present in glomeruli of NZB/W F1 mice. , 1991, Clinical immunology and immunopathology.

[26]  G. Settipane,et al.  Corticosteroid effect on immunoglobulins. , 1978, The Journal of allergy and clinical immunology.

[27]  M. Steward,et al.  Changes in immunoglobulin class and subclass of anti-DNA antibodies with increasing age in N/ZBW F1 hybrid mice. , 1976, Clinical and experimental immunology.

[28]  V. Kelley,et al.  An ultrastructural study of the glomerular slit diaphragm in New Zealand black/white mice. , 1976, Laboratory investigation; a journal of technical methods and pathology.

[29]  R. Rossen,et al.  Effects of corticosteroids on immunity in man. I. Decreased serum IgG concentration caused by 3 or 5 days of high doses of methylprednisolone. , 1973, The Journal of clinical investigation.

[30]  B. J. Helyer,et al.  The immunology and pathology of NZB mice. , 1968, Advances in immunology.