Is duloxetine more effective than amitriptyline for painful diabetic neuropathy?

Neuroprotective effect of duloxetine in a mouse model of diabetic neuropathy: Role of glia suppressing mechanisms

AIMS

Painful diabetic neuropathy (PDN) is one of the most frequent complications of diabetes and the current therapies have limited efficacy. This study aimed to study the neuroprotective effect of duloxetine, a serotonin noradrenaline reuptake inhibitor (SNRI), in a mouse model of diabetic neuropathy.

MAIN METHODS

Nine weeks after developing of PDN, mice were treated with either saline or duloxetine (15 or 30 mg/kg) for four weeks. The effect of duloxetine was assessed in terms of pain responses, histopathology of sciatic nerve and spinal cord, sciatic nerve growth factor (NGF) gene expression and on the spinal expression of astrocytes (glial fibrillary acidic protein, GFAP) and microglia (CD₁₁b).

KEY FINDINGS

The present results highlighted that duloxetine (30 mg/kg) increased the withdrawal threshold in von-Frey test. In addition, both doses of duloxetine prolonged the licking time and latency to jump in the hot-plate test. Moreover, duloxetine administration downregulated the spinal expression of both CD₁₁b and GFAP associated with enhancement in sciatic mRNA expression of NGF.

SIGNIFICANCE

The current results highlighted that duloxetine provided peripheral and central neuroprotective effects in neuropathic pain is, at least in part, related to its downregulation in spinal astrocytes and microglia. Further, this neuroprotective effect was accompanied by upregulation of sciatic expression of NGF.

From guideline to patient: a review of recent recommendations for pharmacotherapy of painful diabetic neuropathy

Painful diabetic peripheral neuropathy (DPN) is a common complication of diabetes mellitus, affecting, by some estimates, up to one quarter of diabetic patients. Since 2010, no fewer than 5 major international treatment guidelines for painful DPN have been issued, and there are meaningful differences among them. Duloxetine, pregabalin, gabapentin, and tricyclic antidepressants are the mainstays of treatment, but the choice of which class or agent to use in any given patient should be informed by patient characteristics. This review seeks to describe the differences among the recently issued guidelines, to assess the evidence on which they are based, and to offer insight into the most appropriate treatment choices based on patient characteristics.