Taxanes and platinum derivatives impair Schwann cells via distinct mechanisms

Area of Science:

• Neuroscience
• Pharmacology
• Cell Biology

Background:

• Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect of anti-cancer drugs.
• Taxanes and platinum derivatives are known neurotoxic agents, but their precise mechanisms in CIPN are unclear.
• The role of Schwann cells, crucial for peripheral nerve health, in CIPN pathogenesis requires further investigation.

Purpose of the Study:

• To investigate the direct effects of chemotherapy agents on Schwann cells.
• To elucidate the specific mechanisms by which paclitaxel, cisplatin, and oxaliplatin impact Schwann cell function.
• To determine the contribution of Schwann cell impairment to the development of CIPN.

Main Methods:

• Primary rat Schwann cells and co-cultures with dorsal root ganglion (DRG) neurons were exposed to paclitaxel, cisplatin, and oxaliplatin.
• Cytotoxicity, myelin basic protein expression, and myelin formation were assessed.
• Mitochondrial function and Schwann cell differentiation markers (p75, galectin-3) were analyzed.
• In vivo studies involved repeated paclitaxel injection in mice to examine sciatic nerve Schwann cells.

Main Results:

• Chemotherapy agents induced cytotoxicity and reduced myelin basic protein expression in Schwann cells at lower concentrations than those affecting DRG neurons.
• Myelin formation was disrupted in co-cultures without direct axonal damage.
• Cisplatin and oxaliplatin caused mitochondrial dysfunction in Schwann cells.
• Paclitaxel induced Schwann cell dedifferentiation, marked by increased p75 and galectin-3 expression, both in vitro and in vivo.
• In vivo findings confirmed paclitaxel-induced changes in mouse sciatic nerve Schwann cells.

Conclusions:

• Taxanes and platinum derivatives directly impair Schwann cells, contributing to CIPN.
• Paclitaxel induces Schwann cell dedifferentiation, while platinum derivatives cause mitochondrial dysfunction.
• These Schwann cell-specific effects, alongside direct neurotoxicity, are critical in CIPN development.