Protective effect of acetyl-L-carnitine on the apoptotic pathway of peripheral neuropathy

Eur J Neurosci. 2007 Aug;26(4):820-7. doi: 10.1111/j.1460-9568.2007.05722.x.

Abstract

Peripheral neuropathies are widespread disorders induced by autoimmune diseases, drug or toxin exposure, infections, metabolic insults or trauma. Nerve damage may cause muscle weakness, altered functionalities and sensitivity, and a chronic pain syndrome characterized by allodynia and hyperalgesia. Pathophysiological mechanisms related to neuropathic disease are associated with mitochondrial dysfunctions that lead to the activation of the apoptotic cascade. In a model of peripheral neuropathy, obtained by the loose ligation of the rat sciatic nerve (CCI), we describe a nerve apoptotic state that encompasses the release of cytochrome C in the cytosol, the activation of caspase 3, and the fragmentation of the genome. Animal treatment with acetyl-L-carnitine (ALCAR), but not with L-carnitine (L-Carn) or Gabapentin, prevents apoptosis induction. ALCAR reduces cytosolic cytochrome C and caspase 3 active fragments expression in a significant manner with respect to saline treatment. Accordingly, ALCAR treatment impairs caspase 3 protease activity, as demonstrated by reduced levels of cleaved PARP. Finally, ALCAR decreases the number of piknotic nuclei. This protection correlates with the induction of X-linked inhibitor apoptosis protein (XIAP). Taken together these results show that CCI is a valuable model to investigate neuropathies-related apoptosis phenomena and that ALCAR is able to prevent regulated cell death in the damaged sciatic nerve.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcarnitine / pharmacology*
  • Animals
  • Apoptosis / drug effects*
  • Blotting, Western
  • Caspase 3 / metabolism
  • Cytochromes c / metabolism
  • Cytosol / metabolism
  • DNA Fragmentation
  • Hyperalgesia / physiopathology
  • In Situ Nick-End Labeling
  • Male
  • Nerve Degeneration / pathology
  • Nootropic Agents / pharmacology*
  • Peripheral Nervous System Diseases / pathology*
  • Poly(ADP-ribose) Polymerases / biosynthesis
  • Poly(ADP-ribose) Polymerases / genetics
  • Rats
  • Rats, Sprague-Dawley
  • Sciatic Neuropathy / pathology

Substances

  • Nootropic Agents
  • Acetylcarnitine
  • Cytochromes c
  • Poly(ADP-ribose) Polymerases
  • Caspase 3