Heparan sulfate having high 3-O-sulfation rate in glucosamine residues
The present invention provides a novel sulfated polysaccharide having anticoagulant activity. Specifically, the present invention provides a polysaccharide that includes a repetitive structure of a disaccharide unit composed of a hexuronic acid (HexA) residue and a α-D-glucosamine (GlcN) residue and having 13% or higher of a 3-O-sulfation rate in GlcN residues.
1. A polysaccharide having an anticoagulant activity, said polysaccharide comprising a repetitive disaccharide unit having the following general formula (I):
wherein,
R 1 , R 2 , R 4 , and R 5 each independently represent a hydrogen or a sulfate group;
R 3 represents a hydrogen, a sulfate group, or an acetyl group;
at least a portion of the R 3 is the sulfate group;
the rate of the sulfate group as R 4 is 13% or more; and
the rate of the sulfate group as R 5 is 50% or more;
wherein 50% or more of the total number of sugar chains present in said polysaccharide have the following general formula (II):
wherein,
R 1 to R 5 are the same as R 1 to R 5 in said general formula (I); and
n is 3 to 30 as an average value; and
wherein the number average molecular weight measured by gel permeation chromatography using pullulan as a standard is 12000 to 40000;
wherein the ratio of anti-factor Xa activity to anti-factor IIa activity is 1.5 or more.
2. The polysaccharide according to claim 1 , wherein the content rate of said disaccharide unit is 90% or more.
3. The polysaccharide according to claim 1 , wherein 50% or more of the total number of sugar chains present in said polysaccharide have the following general formula (II):
wherein,
R 1 to R 5 are the same as R 1 to R 5 in said general formula (I); and
n is 3 to 15 as the average value.
4. The polysaccharide according to claim 1 , wherein the average number of linked sugar residues is 6 to 60.
5. The polysaccharide according to claim 1 , wherein the average number of linked sugar residues is 6 to 30.
6. The polysaccharide according to claim 1 , wherein the weight average molecular weight measured by gel permeation chromatography using pullulan as a standard is 10000 to 100000.
7. The polysaccharide according to claim 1 , wherein the weight average molecular weight measured by gel permeation chromatography using pullulan as a standard is 15000 to 50000.
8. The polysaccharide according to claim 1 , wherein the rate of iduronic acid residues as hexuronic acid residues in said disaccharide unit is 0% to 70%.
9. The polysaccharide according to claim 1 , wherein the rate of a sulfate group as R 1 is 0% to 80%.
10. The polysaccharide according to claim 1 , wherein the rate of a sulfate group as R 1 in iduronic acid residues is 0% to 100%.
11. The polysaccharide according to claim 1 , wherein the rate of a sulfate group as R 1 in glucuronic acid residues is 0% to 50%.
12. The polysaccharide according to claim 1 , wherein the rate of a sulfate group as R 2 is less than 1%.
13. The polysaccharide according to claim 1 , wherein the rate of a sulfate group as R 3 is 70% to 100%.
14. The polysaccharide according to claim 1 , wherein the rate of a acetyl group as R 3 is 0 to 33%.
15. The polysaccharide according to claim 1 , wherein the rate of a sulfate group as R 4 is 45% or less.
16. The polysaccharide according to claim 1 , wherein the rate of a sulfate group as R 5 is 70% to 100%.
17. The polysaccharide according to claim 1 , comprising a disaccharide unit selected from the group consisting of GlcA-G1cN(NS3S6S), GlcA(2S)-G1cN(NS6S), IdoA(2S)-GlcN(NS6S), GlcA-G1cN(NS6S), IdoA(2S)-G1cN(NS), IdoA(2S)-G1cN(NS3S), IdoA-GlcN(NS6S), GlcA-G1cN(NS), and combinations thereof at a total content rate of 50% or more.
18. The polysaccharide according to claim 1 , wherein the ratio (Mw/Mn) of a weight average molecular weight (Mw) to a number average molecular weight (Mn) measured by gel permeation chromatography using pullulan as a standard is 1.5 or less.
19. The polysaccharide according to claim 1 , which is a free form, or a pharmacologically acceptable salt, or a mixture thereof.
20. The polysaccharide according to claim 19 , wherein said salt is selected from the group consisting of an ammonium salt, a sodium salt, a lithium salt, and a calcium salt.
21. A pharmaceutical composition comprising the polysaccharide according to claim 1 .
22. A method of preventing, ameliorating, and/or treating a symptom attributed to blood coagulation comprising administering the composition according to claim 21 to a subject in need thereof.
23. The method according to claim 22 , wherein said symptom is selected from the group consisting of disseminated intravascular coagulation syndrome, thrombotic embolism, blood coagulation in artificial dialysis, and blood coagulation in extracorporeal circulation.