Berberine reduces neuroglia activation and inflammation in streptozotocin-induced diabetic mice.

We aimed to analyze the action of berberine on the neuropathic pain and neuroglia activation in experimental diabetes mellitus (DM) model. Diabetes in mice was induced by intraperitoneal injection of streptozotocin (STZ) followed by the administration of berberine. Mechanical allodynia and thermal hyperalgesia and activations of microglia and astrocytes were evaluated. The levels of pro-inflammatory cytokines and protein expressions of inflammatory proteins were assessed by enzyme-linked immunosorbent assay (ELISA) and western blot, respectively. Our results revealed the anti-nociceptive effects of berberine in DM mice, supported by the improved mechanical threshold and thermal latency. In addition, berberine suppressed the activations of microglia and astrocytes in the spinal cords of diabetic mice. Berberine inhibited the expression of pro-inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin-6 (IL-6), and interleukin-1β (IL-1β), along with inflammatory proteins including iNOS and COX-2. Berberine suppressed neuropathic pain in STZ-induced diabetic mice, and this effect is related to the reduction on the neuroglia activation and inflammation associated with DM.