Redox and bioenergetic modulation by plumbagin attenuated neuropathic allodynia in mice with diet-induced diabetes.

backgroundPainful diabetic neuropathy represents a substantial health burden, afflicting approximately 30% of individuals with diabetes. Currently available neuropathic pain medications exhibit only limited efficacy, are associated with significant adverse effects, and often result in poor patient adherence. The need for more effective neuropathic pain treatments in diabetic patients remains critical. This study aimed to evaluate the potential pain-relieving effects of plumbagin, a naturally occurring naphthoquinone, in a mouse model of persistent neuropathic pain associated with diet-induced type 2 diabetes.

methodsMale C57BL/6 J mice were fed a high-fat diet for eight weeks to induce type 2 diabetes. Pain-like behaviors were assessed using the von Frey test for mechanical allodynia and the acetone test for cold allodynia. The underlying mechanisms related to redox status and bioenergetics were explored using both in vivo and in vitro approaches.

resultsChronic administration of plumbagin not only alleviated established mechanical and cold allodynia in mice with type 2 diabetes but also delayed the onset of neuropathic pain under a preventive regimen at lower doses. While plumbagin did not impact on metabolic characteristics of diabetic mice, it corrected mitochondrial bioenergetic deficits in dorsal root ganglion neurons, alleviated oxidative stress in pain-related tissues, and enhanced both sciatic nerve conduction velocity and blood flow. Importantly, the analgesic effects of plumbagin were found to be modulated through pharmacological manipulation of mitochondrial bioenergetic function and redox balance.

conclusionsThese findings demonstrate the analgesic activity of plumbagin in mice with diet-induced type 2 diabetes, an effect that is mechanistically linked to its capacity to enhance mitochondrial bioenergetics and attenuate oxidative stress.