Curcumin Ameliorates the Experimental Diabetic Peripheral Neuropathy through Promotion of NGF Expression in Rats

Area of Science:

• Neuroscience
• Pharmacology
• Biochemistry

Background:

• Diabetic peripheral neuropathy (DPN) is linked to Schwann cell (SC) apoptosis and reduced nerve growth factor (NGF).
• Curcumin, a turmeric compound, has known therapeutic properties but is understudied in DPN models.
• Understanding curcumin's mechanism in DPN is crucial for developing new treatments.

Purpose of the Study:

• To investigate the therapeutic effects of curcumin on DPN in a rat model.
• To elucidate the underlying mechanisms, focusing on SC apoptosis and NGF expression.

Main Methods:

• DPN was induced in Sprague-Dawley rats using a high-fat/sugar diet and streptozotocin (STZ).
• Rats were treated with varying doses of curcumin (50, 100, 150 mg/kg) for 4 weeks.
• Evaluated outcomes included body weight, fasting blood glucose, nerve conduction velocity, sciatic nerve ultrastructure, SC apoptosis (TUNEL assay), and NGF levels (Western blot, ELISA).

Main Results:

• Curcumin did not significantly affect body weight or fasting blood glucose.
• Curcumin treatment (100 and 150 mg/kg) improved nerve function (mechanical withdrawal threshold, nerve conduction velocity) and sciatic nerve ultrastructure.
• Curcumin significantly reduced SC apoptosis across all tested doses.
• The highest curcumin dose (150 mg/kg) most effectively increased NGF expression in sciatic nerves and serum.

Conclusions:

• Curcumin demonstrates significant neuroprotective effects in a DPN rat model.
• These benefits are mediated by the inhibition of SC apoptosis and the promotion of NGF expression.
• Curcumin represents a promising therapeutic agent for managing diabetic peripheral neuropathy.