Acetyl-L-carnitine: from a biological curiosity to a drug for the peripheral nervous system and beyond

Abstract

Acetyl-L-carnitine (ALC) is a molecule derived from acetylation of carnitine in the mitochondria. Carnitine acetylation enables the function of CoA and facilitates elimination of oxidative products. Beyond this metabolic activity, ALC provides acetyl groups for acetylcholine synthesis, exerts a cholinergic effect and optimizes the balance of energy processes. Acetylcarnitine supplementation induces neuroprotective, neurotrophic and analgesic effects in the peripheral nervous system. In the recent studies, ALC, by acting as a donor of acetyl groups to NF-kb p65/RelA, enhanced the transcription of the GRM2 gene encoding the mGLU2 receptors, inducing long-term upregulation of the mGluR2, evidencing therefore that its long-term analgesic effects are dependent on epigenetic modifications. Several studies, including double-blind, placebo-controlled, parallel group studies and few open studies showed the effect of ALC in diseases characterized by neuropathies and neuropathic pain: the studies included diabetic neuropathy, HIV and antiretroviral therapy–induced neuropathies, neuropathies due to compression and chemotherapeutic agents. Double-blinded studies involved 1773 patients. Statistical evaluations evidenced reduction of pain, improvements of nerve function and trophism. In conclusion, ALC represents a consistent therapeutic option for peripheral neuropathies, and its complex effects, neurotrophic and analgesic, based on epigenetic mechanism, open new pathways in the study of peripheral nerve disease management.

Keywords::

• Acetyl-L-Carnitine
• metabotropic glutamate receptors
• neuropathic pain
• neuropathy
• pain

Financial & competing interests disclosure

All authors have acted as consultants for Sigma-Tau SPA, the pharmaceutical company manufacturing l-acetyl carnitine. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.