title: New therapeutic and biomarker discovery for peripheral diabetic neuropathy: PARP inhibitor, nitrotyrosine, and tumor necrosis factor-{alpha}.
abstract: This study evaluated poly(ADP-ribose) polymerase (PARP) inhibition as a new therapeutic approach for peripheral diabetic neuropathy using clinically relevant animal model and endpoints, and nitrotyrosine (NT), TNF-alpha, and nitrite/nitrate as potential biomarkers of the disease. Control and streptozotocin-diabetic rats were maintained with or without treatment with orally active PARP inhibitor 10-(4-methyl-piperazin-1-ylmethyl)-2H-7-oxa-1,2-diaza-benzo[de]anthracen-3-one (GPI-15,427), 30 mg kg(-1) d(-1), for 10 wk after first 2 wk without treatment. Therapeutic efficacy was evaluated by poly(ADP-ribosyl)ated protein expression (Western blot analysis), motor and sensory nerve conduction velocities, and tibial nerve morphometry. Sciatic nerve and spinal cord NT, TNF-alpha, and nitrite/nitrate concentrations were measured by ELISA. NT localization in peripheral nervous system was evaluated by double-label fluorescent immunohistochemistry. A PARP inhibitor treatment counteracted diabetes-induced motor and sensory nerve conduction slowing, axonal atrophy of large myelinated fibers, and increase in sciatic nerve and spinal cord NT and TNF-alpha concentrations. Sciatic nerve NT and TNF-alpha concentrations inversely correlated with motor and sensory nerve conduction velocities and myelin thickness, whereas nitrite/nitrate concentrations were indistinguishable between control and diabetic groups. NT accumulation was identified in endothelial and Schwann cells of the peripheral nerve, neurons, astrocytes, and oligodendrocytes of the spinal cord, and neurons and glial cells of the dorsal root ganglia. The findings identify PARP as a compelling drug target for prevention and treatment of both functional and structural manifestations of peripheral diabetic neuropathy and provide rationale for detailed evaluation of NT and TNF-alpha as potential biomarkers of its presence, severity, and progression.
authors.affiliation: Pennington Biomedical Research Center, Louisiana State University System, 6400 Perkins Road, Baton Rouge, Louisiana 70808, USA.
authors.forename: Viktor R
authors.initials: VR
authors.lastname: Drel
authors.forename: Sergey
authors.initials: S
authors.lastname: Lupachyk
authors.forename: Hanna
authors.initials: H
authors.lastname: Shevalye
authors.forename: Igor
authors.initials: I
authors.lastname: Vareniuk
authors.forename: Weizheng
authors.initials: W
authors.lastname: Xu
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Delamere
authors.forename: Mohammad
authors.initials: M
authors.lastname: Shahidullah
authors.forename: Barbara
authors.initials: B
authors.lastname: Slusher
authors.forename: Irina G
authors.initials: IG
authors.lastname: Obrosova
mesh_terms: D000818:Animals; D015153:Blotting, Western; D003929:Diabetic Neuropathies / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D004791:Enzyme Inhibitors / Q000627:therapeutic use*; D004797:Enzyme-Linked Immunosorbent Assay; D007150:Immunohistochemistry; D008297:Male; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D009566:Nitrates; D009573:Nitrites; D000067856:Poly(ADP-ribose) Polymerase Inhibitors; D014409:Tumor Necrosis Factor-alpha; C002744:3-nitrotyrosine; D014443:Tyrosine; D011065:Poly(ADP-ribose) Polymerases