Peripheral neuropathy in rats exposed to dichloroacetate

Area of Science:

• Neuroscience
• Toxicology
• Biochemistry

Background:

• Dichloroacetate (DCA) is investigated for treating mitochondrial diseases.
• Clinical use of DCA is limited by dose-dependent peripheral neuropathy.
• The underlying mechanisms of DCA-induced neuropathy remain unclear.

Purpose of the Study:

• To investigate the mechanisms of dichloroacetate-induced peripheral neuropathy.
• To evaluate the effects of DCA on nerve function and structure in rats.
• To establish a rat model for studying DCA neuropathy.

Main Methods:

• Oral administration of DCA (50-500 mg/kg/day) to juvenile and adult rats for up to 16 weeks.
• Behavioral testing for tactile allodynia and thermal hypoalgesia.
• Nerve conduction velocity measurements.
• Morphometric analysis of peripheral nerves and spinal cord.
• Assessment of oxidative stress markers in nerves.

Main Results:

• DCA induced tactile allodynia and, at higher doses, thermal hypoalgesia in rats.
• Nerve conduction slowing was observed, more significantly in adult rats.
• Morphometric analysis revealed reduced axonal caliber in myelinated peripheral nerve fibers.
• Accumulation of oxidative stress markers was detected in DCA-treated nerves.
• No overt axonal or glial cell abnormalities were found.

Conclusions:

• DCA induces peripheral neuropathy in rats, affecting both juvenile and adult animals.
• The neuropathy involves metabolic disturbances and structural changes, primarily affecting axons.
• DCA-induced neuropathy is characterized by reduced axonal caliber and oxidative stress.
• The DCA-treated rat model offers insights into neuropathy pathogenesis and potential therapeutic strategies.