Plasma glucosylceramide deficiency as risk factor for thrombosis and modulator of anticoagulant protein C

A pharmaceutical composition comprising at least one antithrombotic factor, wherein said at least one factor further comprises:

• (a) at least one neutral glycolipid;
• or
• (b) at least one neutral glycolipid, wherein the neutral glycolipid comprises a formula:
• R—sugar—linkage—ceramide, wherein R is hydrogen or at least one saccharide unit;
• and a pharmaceutically acceptable carrier.

A method of determining a neutral glycolipid concentration in plasma or serum comprising:

• a) extraction of lipids from plasma or serum to form a plasma lipid extract;
• b) isolation of the neutral glycolipid by chromatographic separation of the plasma lipid extract;
• and
• c) determination of the concentration of isolated neutral glycolipid by comparison to reference neutral glycolipid standards.

A method of enhancing antithrombotic or anti-inflammatory activity or reducing risk for thrombosis in an individual in need thereof, comprising:

• administering to the individual at least one antithrombotic factor selected from the group consisting of:
• (a) at least one neutral glycolipid;
• (b) at least one neutral glycolipid, wherein the neutral glycolipid comprises a formula:
• R—sugar—linkage—ceramide, wherein R is hydrogen or at least one saccharide unit;
• (c) at least one neutral glycolipid, wherein the neutral glycolipid or glycolipids are in vesicle form;
• and
• (d) at least one neutral glycolipid, wherein the neutral glycolipid or glycolipids are in vesicle form, wherein the vesicle further comprises at least one lipid;
• wherein, said antithrombotic factor is in an amount effective to enhance the antithrombotic or anti-inflammatory activity or to reduce the individual's risk for thrombosis.

A method of screening for antithrombotic factors from candidate neutral glycolipids comprising:

• (a) incubating the candidate neutral glycolipid with a plasma sample with:
• (1) exogenous activated protein C, exogenous protein C and an exogenous reagent that transforms exogenous protein C to activated protein C or an exogenous reagent that transforms endogenous protein C to activated protein C;
• (2) an exogenous reagent (I) which at least partially activates a coagulation factor of the blood coagulation system of said plasma sample;
• and optionally;
• (3) an exogenous substrate for an enzyme wherein the activity of said enzyme is influenced by neutral glycolipid, to prepare a final assay medium;
• (b) measuring a substrate conversion rate for a coagulation factor directly or indirectly activated in step (a), the activity of which is influenced by neutral glycolipid;
• and
• (c) comparing said substrate conversion rate measure in step (b) with a standard value obtained from plasma in the absence of said neutral glycolipid wherein when said substrate conversion rate obtained for said neutral glycolipid in step (b) is lower than the standard value, said candidate neutral glycolipid is an antithrombotic factor.