Compositions and methods for treating mitochondrial neurogastrointestinal encephalopathy
Disclosed herein are compositions and methods of treating disclosure provides for compounds for use in treating Mitochondrial Neurogastrointestinal Encephalopathy Syndrome (MNGIE). In some embodiments, the compounds have cell penetrating activity and thymidine phosphorylase activity. In certain embodiments, the compounds disclosed herein comprise: a) at least one cell-penetrating peptide (CPP) moiety; and b) a thymidine phosphorylase, or an active fragment or analog thereof (TP), wherein the CPP is coupled, directly or indirectly, to TP.
1 . A method of treating Mitochondrial Neurogastrointestinal Encephalopathy (MNGIE) in an individual in need thereof, comprising administering a compound comprising:
a) at least one cyclic cell-penetrating peptide (CPP) having a structure of Formula III:
wherein:
each of AA 1 , AA 2 , AA 3 , AA 4 , AA u and AA z is a D or L amino acid;
m and n are independently selected from a number from 0 to 6; and
wherein the peptide of Formula III comprises at least two arginine and at least two hydrophobic amino acids;
b) at least one thymidine phosphorylase, or an active fragment or analog thereof (TP), wherein the TP has an amino acid sequence that is at least 97% identical to any one of SEQ ID NOS: 1-13; and
c) at least one linker (L) that conjugates each CPP and the TP.
2 . The method of claim 1 , wherein the individual having MNGIE has thymidine phosphorylase expression or activity levels that are less than 1-99% of normal thymidine phosphorylase expression or activity levels in an individual not afflicted with MNGIE.
3 . The method of claim 1 , wherein the compound is administered to the individual orally or parenterally.
4 . The method of claim 1 , wherein administration of the compound reduces extracellular and intracellular levels of thymidine in the individual, as compared to the average extracellular and intracellular levels of thymidine in the individual before treatment.
5 . The method of claim 4 , wherein the intracellular and extracellular levels of thymidine in the individual are reduced by more than 5%, as compared to the average level of thymidine in the individual before treatment.
6 . The method of claim 1 , wherein the TP has the amino acid sequence of any one of SEQ ID NOS: 1-13.
7 . The method of claim 1 , wherein L is bound to the side chain of an amino acid on each CPP, and each of the L is also bound to the N-terminus of the TP or to the side chain of a lysine in the TP.
8 . The method of claim 1 , wherein the CPP has a structure of any one of Formula IV-A to IV-D:
wherein:
each of AA H1 and AA H2 are independently a D or L hydrophobic amino acid;
at each instance and when present, each of AA U and AA Z are independently a D or L amino acid; and
m and n are independently selected from an integer from 0 to 6.
9 . The method of claim 8 , wherein the compound of any one of Formula IV-A to IV-D comprises at least three consecutive arginine, and at least three-consecutive hydrophobic aromatic amino acids.
10 . The method of claim 1 , wherein L is: (a) one or more D or L amino acids, each of which is optionally substituted; (b) alkylene, alkenylene, alkynylene, carbocyclyl, or heterocyclyl, each of which is optionally substituted; or (c) —(R 1 —X—R 2 )z-, wherein each of R 1 and R 2 , at each instance, are independently selected from alkylene, alkenylene, alkynylene, carbocyclyl, and heterocyclyl, each X is independently NR 3 , —NR 3 C(O)—, S, and O, wherein R 3 is independently selected from H, alkyl, alkenyl, alkynyl, carbocyclyl, and heterocyclyl, wherein each alkylene, alkenylene, alkynylene, carbocyclyl, and heterocyclyl is optionally substituted, and wherein z is an integer from 1 to 20; or combinations thereof.
11 . The method of claim 1 , wherein L has a structure according to Formula II-A′ or II-B′:
and wherein
M is absent or a group bound to TP;
AA S is a side chain or terminus of an amino acid on the CPP;
o is an integer from 0 to 10;
p is an integer from 0 to 10;
q is an integer from 1 to 50; and
r is 0 or 1.
12 . The method of claim 11 , wherein M is present and comprises an alkylene, alkenylene, alkynylene, carbocyclyl, or heterocyclyl, each of which is optionally substituted.
13 . The method of claim 12 , wherein M is present and selected from the group consisting of:
wherein each R is independently an alkyl, alkenyl, alkynyl, carbocyclyl, or heterocyclyl.
14 . The method of claim 11 , wherein M is
15 . The method of claim 12 , wherein M is present and is covalently bound to the N-terminus of TP.
16 . The method of claim 1 , wherein the pharmaceutical composition comprises a structure according to Formula V-A1, V-A2, or V-A3:
wherein q is an integer from 1 to 50.
17 . The method of claim 1 , wherein the compound comprises a structure according Formula V-B1 or V-B2:
18 . The method of claim 1 , wherein the compound comprises a structure according Formula V-B3 or V-B4:
19 . The method of claim 18 , wherein the TP has the amino acid sequence of SEQ ID NO: 3.
20 . The method of claim 1 , wherein the compound comprises from 2 to 12 CPP.
21 . The method of claim 1 , wherein each TP independently further comprises at least one water-soluble polymer conjugated to the TP.
22 . The method of claim 21 , wherein the water-soluble polymer comprises a polyethylene glycol (PEG) residue with a molecular weight ranging from 1 kDa to 20 kDa.