Effect of Tanshinone IIA intrathecal injections on pain and spinal inflammation in mice with bone tumors

The study aimed to investigate the effect of intrathecal injections of Tanshinone IIA on thermal hyperalgesia in a mouse model of bone cancer-pain. Spinal IL-1β, IL-6, TNF-α expression levels were analyzed. C3H/HeNCrlVr male mice were assigned to groups that either received dose-dependent injections of Tanshinone IIA, or the DMSO + Sham, Tanshinone IIA + Sham, DMSO + Tumor, and Control groups. Paw withdrawal thermal latency (PWTL) was measured with a radiant heat stimulus and mRNA expression levels were determined using real-time PCR. Fourteen days post-injection, PWTL in the DMSO + Tumor group was lower than that in the controls (P < 0.05). Twenty-one days post-injection, compared with the Control group, there was no significant difference in PWTL and IL-1β, IL-6, and TNF-α expression levels between the Tanshinone IIA + Sham and DMSO + Sham groups (P > 0.05). PWTL in the DMSO + Tumor group was significantly lower than the Control group (P < 0.05), while the expression levels of IL-1β, IL-6, and TNF-α were significantly higher than controls. Compared with the DMSO + Tumor group, PWTLs were higher in the Tanshinone IIA - 20-μg and 40-μg groups, while expression levels of IL-1β, IL-6, and TNF-α were significantly lower (P < 0.05). These measures were not significantly different between the Tanshinone IIA 10 μg and the DMSO + Tumor groups (P > 0.05). In conclusion, Tanshinone IIA may inhibit the release of inflammatory cytokines, such as, IL-1 β, IL-6 α, TNF-α.