Fig. 7
From: Metformin reduces morphine tolerance by inhibiting microglial-mediated neuroinflammation
Metformin inhibits the inflammation induced by morphine in vivo. a Metformin increased AMPK-Tyr172 phosphorylation in mice spinal cords in a dose-dependent manner (n = 4). b Metformin inhibited morphine-induced up-regulation of TLR-4 mRNA in spinal cords (n = 4). c Metformin inhibited morphine-induced up-regulation of p38 phosphorylation in spinal cords (n = 4). d Metformin inhibited morphine-induced IL-1β and TNF-α protein expression in spinal cords (n = 4). The lumbar spines (L1–L6) were collected and analyzed 15 min after metformin (50, 100, and 200 mg/kg, i.p.) administration. Significant difference was revealed following one-way analysis of variance (*p < 0.05; **p < 0.01; Bonferroni’s post hoc tests)