Therapeutic Strategies for Gaucher Disease: Miglustat (NB-DNJ) as a Pharmacological Chaperone for Glucocerebrosidase and the Different Thermostability of Velaglucerase Alfa and Imiglucerase

Abstract

Gaucher disease (GD) is a disorder of glycosphingolipid metabolism caused by deficiency of lysosomal glucocerebrosidase (GlcCerase) activity, due to conformationally or functionally defective variants, resulting in progressive deposition of glycosylceramide in macrophages. The glucose analogue, N-butyldeoxynojirimycin (NB-DNJ, miglustat), is an inhibitor of the ceramide-specific glycosyltransferase, which catalyzes the first step of glycosphingolipid biosynthesis and is currently approved for the oral treatment of type 1 GD. In a previous work, we found a GlcCerase activity increase in cell cultures in the presence of NB-DNJ, which could imply that this compound is not only a substrate reducer but also a pharmacological chaperone or inhibitor for GlcCerase degradation. In this work we compare imiglucerase (the enzyme currently used for replacement therapy) and velaglucerase alfa (a novel therapeutic enzyme form) in terms of conformational stability and enzymatic activity, as well as the effect of NB-DNJ on them. The interaction between these enzymes and NB-DNJ was studied by isothermal titration calorimetry. Our results reveal that, although velaglucerase alfa and imiglucerase exhibit very similar activity profiles, velaglucerase alfa shows higher in vitro thermal stability and is less prone to aggregation/precipitation, which could be advantageous for storage and clinical administration. In addition, we show that at neutral pH NB-DNJ binds to and enhances the stability of both enzymes, while at mildly acidic lysosomal conditions it does not bind to them. These results support the potential role of NB-DNJ as a pharmacological chaperone, susceptible of being part of pharmaceutical formulation or combination therapy for GD in the future.

Gaucher's Disease and Cancer: A Sphingolipid Perspective

“…28,36 Miglustat is an imino sugar analog of glucose that is an inhibitor of glucosylceramide synthase. 28,38,42,46,47 Miglustat is currently the only FDA-approved SRT for Gaucher’s disease. Eliglustat tartrate is another SRT that is currently in phase III clinical trials after the completion of a successful phase II clinical trial.…”

“…47,50,51 Other therapeutic options have been or are being considered for Gaucher’s disease including bone marrow transplantation (for non-neurological Gaucher’s disease), gene therapy, and pharmacological chaperone therapy. 28,30,32,46,47,50–52 Isofagomine tartrate is a pharmacological chaperone that was under recent pre-clinical development and was designed to bind to and help stabilize the misfolded glucocerebrosidase that arises from the specific N370S mutation. 52 However after initial clinical trials with minimal “clinically meaningful improvements,” further clinical development of isofagomine tartrate was discontinued (October 2, 2009 press release from Amicus Therapeutics).…”

Glycotherapy: New Advances Inspire a Reemergence of Glycans in Medicine

“…Miglustat (Zavesca, N-butyl-deoxynojirimycin) is a drug developed by Actelion and used primarily to treat the lysosomal storage disease type 1 Gaucher disease. Miglustat is an imino sugar first synthesized by Butters and Dwek who found that N-alkylated analogs of the natural product deoxynojirimycin were inhibitors of the glucosyl-transferase involved in glucosylceramide biosynthesis (Abian et al, 2011; Platt et al, 1997). Treatment with miglustat was shown to alleviate the built up of sphingolipid seen in Gaucher disease.…”

The development and use of small molecule inhibitors of glycosphingolipid metabolism for lysosomal storage diseases

“…For example, the effects of miglustat may be due to its modest effects as a glucosylceramide synthase inhibitor or rather be the result of chaperone effects resulting from its direct binding to GBA ( 39 ). Miglustat cocrystallizes with lysosomal glucocerebrosidase and its binding is greater at neutral compared with acidic pH ( 40 ).…”