Levo-Tetrahydropalmatine Attenuates Bone Cancer Pain by Inhibiting Microglial Cells Activation.

Abstract

OBJECTIVE:

The present study is to investigate the analgesic roles of L-THP in rats with bone cancer pain caused by tumor cell implantation (TCI).

METHODS:

Thermal hyperalgesia and mechanical allodynia were measured at different time points before and after operation. L-THP (20, 40, and 60 mg/kg) were administrated intragastrically at early phase of postoperation (before pain appearance) and later phase of postoperation (after pain appearance), respectively. The concentrations of TNF-α, IL-1β, and IL-18 in spinal cord were measured by enzyme-linked immunosorbent assay. Western blot was used to test the activation of astrocytes and microglial cells in spinal cord after TCI treatment.

RESULTS:

TCI treatment induced significant thermal hyperalgesia and mechanical allodynia. Administration of L-THP at high doses significantly prevented and/or reversed bone cancer-related pain behaviors. Besides, TCI-induced activation of microglial cells and the increased levels of TNF-α and IL-18 were inhibited by L-THP administration. However, L-THP failed to affect TCI-induced astrocytes activation and IL-1β increase.

CONCLUSION:

This study suggests the possible clinical utility of L-THP in the treatment of bone cancer pain. The analgesic effects of L-THP on bone cancer pain maybe underlying the inhibition of microglial cells activation and proinflammatory cytokines increase.

• Authors: Mao-Yin Zhang, Yue-Peng Liu, Lian-Yi Zhang, Dong-Mei Yue, Dun-Yi Qi, Gong-Jian Liu, Su Liu
• Journal: Mediators of inflammation (Mediators Inflamm) Vol. 2015 Pg. 752512 ( 2015) ISSN: 1466-1861 [Electronic] United States
• PMID: 26819501 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Berberine Alkaloids
• Interleukin-18
• Tumor Necrosis Factor-alpha
• tetrahydropalmatine

Topics

• Animals
• Berberine Alkaloids (pharmacology)
• Bone Neoplasms (physiopathology)
• Dose-Response Relationship, Drug
• Female
• Hyperalgesia (drug therapy)
• Interleukin-18 (analysis)
• Microglia (drug effects, physiology)
• Neoplasm Transplantation
• Pain, Intractable (drug therapy)
• Rats
• Rats, Sprague-Dawley
• Tumor Necrosis Factor-alpha (analysis)