title: Chronic treatment with D-chiro-inositol prevents autonomic and somatic neuropathy in STZ-induced diabetic mice.
abstract: OBJECTIVE
  D-chiro-inositol (DCI) has been shown to prevent and reverse endothelial dysfunction in diabetic rats and rabbits. The present study evaluates the preventive effect of DCI on experimental diabetic neuropathy (DN).
  
  
  METHODS
  Streptozotocin-induced (STZ) diabetic mice were treated by oral gavage for 60 days with DCI (20 mg/kg/12 h) or saline (NaCl 0.9%; 0.1 ml/10 g/12 h; Diab) and compared with euglycaemic groups treated with saline (0.1 ml/10 g/12 h; Eugly). We compared the response of the isolated sciatic nerve, corpora cavernosa or vas deferens to electrical stimulation.
  
  
  RESULTS
  The electrically evoked compound action potential of the sciatic nerve was greatly blunted by diabetes. The peak-to-peak amplitude (PPA) was decreased from 3.24 ± 0.7 to 0.9 ± 0.2 mV (p < 0.05), the conduction velocity (CV) of the first component was reduced from 46.78 ± 4.5 to 26.69 ± 3.8 ms (p < 0.05) and chronaxy was increased from 60.43 ± 1.9 to 69.67 ± 1.4 ms (p < 0.05). These parameters were improved in nerves from DCI-treated mice (p < 0.05). PPA in the DCI group was 5.79 ± 0.8 mV (vs. 0.9 ± 0.2 mV-Diab; p < 0.05) and CV was 45.91 ± 3.6 ms (vs. 26.69 ± 3.8 ms-Diab; p < 0.05). Maximal relaxation of the corpus cavernosum evoked by electrical stimulation (2-64 Hz) in the Diab group was 36.4 ± 3.8% compared to 65.4 ± 2.8% in Eugly and 59.3 ± 5.5% in the DCI group (p < 0.05). Maximal contraction obtained in the vas deferens was 38.0 ± 9.2% in Eugly and 11.5 ± 2.6% in Diab (decrease of 69.7%; p < 0.05), compared to 25.2 ± 2.3% in the DCI group (p < 0.05 vs. diabetic). Electron microscopy of the sciatic nerves showed prevention of neuronal damage.
  
  
  CONCLUSIONS
  DCI has a neuroprotective action in both autonomic and somatic nerves in STZ-induced DN.
authors.affiliation: Department of Physiology and Pharmacology, Superior Institute of Biomedical Sciences, Fortaleza, Ceará, Brazil.
authors.forename: V X
authors.initials: VX
authors.lastname: Farias
authors.forename: F H P
authors.initials: FH
authors.lastname: Macêdo
authors.forename: M B
authors.initials: MB
authors.lastname: Oquendo
authors.forename: A R
authors.initials: AR
authors.lastname: Tomé
authors.forename: S N
authors.initials: SN
authors.lastname: Báo
authors.forename: D O S
authors.initials: DO
authors.lastname: Cintra
authors.forename: C F
authors.initials: CF
authors.lastname: Santos
authors.forename: A A C
authors.initials: AA
authors.lastname: Albuquerque
authors.forename: D B
authors.initials: DB
authors.lastname: Heimark
authors.forename: J
authors.initials: J
authors.lastname: Larner
authors.forename: M C
authors.initials: MC
authors.lastname: Fonteles
authors.forename: J H
authors.initials: JH
authors.lastname: Leal-Cardoso
authors.forename: N R F
authors.initials: NR
authors.lastname: Nascimento
mesh_terms: D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000503:physiopathology; D003929:Diabetic Neuropathies / Q000139:chemically induced* / Q000503:physiopathology / Q000517:prevention & control; D004558:Electric Stimulation; D007294:Inositol / Q000008:administration & dosage* / Q000494:pharmacology; D008297:Male; D051379:Mice; D012584:Sciatic Nerve / Q000187:drug effects* / Q000503:physiopathology; D013311:Streptozocin / Q000008:administration & dosage* / Q000494:pharmacology
chemical_list: D007294:Inositol; D013311:Streptozocin