title: Oxytocin provides protection against diabetic polyneuropathy in rats.
abstract: OBJECTIVE
  The aim of the present study is to investigate the protective effects of oxytocin (OT) on diabetic neuropathy (DNP) in rats.
  
  
  METHODS
  Eighteen rats were used to induce diabetes using single dose streptozotocin (STZ, 60 mg/kg). Diabetic DNP was verified by electromyography (EMG) and motor function test on 21st day following STZ injection. Six rats served as naïve control group and received no drug (n = 6). Following EMG, diabetic rats were randomly divided into three groups and administered with either 1 ml/kg saline or 80 μg/kg OT or 160 μg/kg OT intraperitoneally for four weeks. Then, EMG, motor function test, biochemical analysis (plasma lipid peroxides and glutathione), histological, and immunohistochemical analysis of sciatic nerves (bax, caspase 3, caspase 9, and NGF) were performed.
  
  
  RESULTS
  Diabetic rats developed neuropathy, which was apparent from decreased compound muscle action potentials amplitudes and prolonged distal latency in saline-treated rats (p < 0.001) whereas 160 μg/kg OT significantly improved EMG findings. OT treatment significantly lessened the thickening of perineural fibrosis when compared with saline group (p < 0.001). Besides, OT significantly reduced plasma lipid peroxides (p < 0.05) and increased glutathione levels in diabetic rats (p < 0.001). The sciatic nerves of saline-treated rats showed considerable increase in bax, caspase 3 and caspase 8 expressions (p < 0.001) while OT treatment significantly suppressed these apoptosis markers. Also, OT improved NGF expression in diabetic rats compared to saline group.
  
  
  CONCLUSIONS
  Present results demonstrate that OT appears to alleviate harmful effects of hyperglycemia on peripheral neurons by suppressing inflammation, oxidative stress and apoptotic pathways.
authors.affiliation: a Department of Physiology , Istanbul Bilim University School of Medicine , Istanbul , Turkey.
authors.forename: Oytun
authors.initials: O
authors.lastname: Erbas
authors.affiliation: b Department of Physiology , Ege University School of Medicine , Izmir , Turkey.
authors.forename: Dilek
authors.initials: D
authors.lastname: Taşkıran
authors.affiliation: c Department of Histology and Embryology , Ege University School of Medicine , Izmir , Turkey.
authors.forename: Fatih
authors.initials: F
authors.lastname: Oltulu
authors.affiliation: c Department of Histology and Embryology , Ege University School of Medicine , Izmir , Turkey.
authors.forename: Altuğ
authors.initials: A
authors.lastname: Yavaşoğlu
authors.affiliation: b Department of Physiology , Ege University School of Medicine , Izmir , Turkey.
authors.forename: Saylav
authors.initials: S
authors.lastname: Bora
authors.affiliation: d Department of Anatomy , Ege University School of Medicine , Izmir , Turkey.
authors.forename: Okan
authors.initials: O
authors.lastname: Bilge
authors.affiliation: e Department of Neurology , Giresun State Hospital , Giresun , Turkey.
authors.forename: Bilge Piri
authors.initials: BP
authors.lastname: Çınar
authors.affiliation: b Department of Physiology , Ege University School of Medicine , Izmir , Turkey.
authors.forename: Gönül
authors.initials: G
authors.lastname: Peker
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D003929:Diabetic Neuropathies / Q000139:chemically induced / Q000503:physiopathology / Q000517:prevention & control*; D004195:Disease Models, Animal; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000187:drug effects / Q000502:physiology; D005978:Glutathione / Q000097:blood; D008054:Lipid Peroxides / Q000097:blood; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D018482:Muscle, Skeletal / Q000187:drug effects / Q000473:pathology; D020932:Nerve Growth Factor / Q000378:metabolism; D010120:Oxytocics / Q000627:therapeutic use*; D010121:Oxytocin / Q000627:therapeutic use*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012583:Schwann Cells / Q000187:drug effects / Q000473:pathology; D012584:Sciatic Nerve / Q000473:pathology; D013311:Streptozocin / Q000633:toxicity; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D008054:Lipid Peroxides; D010120:Oxytocics; D051028:bcl-2-Associated X Protein; D010121:Oxytocin; D013311:Streptozocin; D020932:Nerve Growth Factor; D053148:Caspase 3; D053181:Caspase 8; D005978:Glutathione
keywords: CMAPs: Compound muscle action potentials; DNP: Diabetic polyneuropathy; DRG: Dorsal root ganglion; Diabetes mellitus; Diabetic polyneuropathy; EMG; EMG: Electromyography; GSH: Glutathione; MDA: Malondialdehyde; NCV: Neuron conduction velocity; OT: Oxytocin; Oxidative stress; Oxytocin; PKC: Protein kinase C; ROS: Reactive oxygen species; STZ: Streptozotocin; TBARS: Thiobarbituric acid reactive substance; TNF-α: Tumor necrosis factor- alpha