Evidence Details for Pomc
PMID Title Journal Year Abstract
19607689 Substance P and beta-endorphin mediate electro-acupuncture induced analgesia in mouse cancer pain model. J Exp Clin Cancer Res. 2009 Jul 16;28(1):102. doi: 10.1186/1756-9966-28-102. 2009 Jul 16 BACKGROUND: Opioid analgesics are generally used to combat the pain associated with cancerous conditions. These agents not only inhibit respiratory function and cause constipation, but also induce other significant side effects such as addiction and tolerance, all of which further contribute to a reduced quality of life for cancer patients. Thus, in the present study, the effects of electro-acupuncture treatment (EA) on mechanical allodynia were examined in a cancer pain mouse model. METHODS: In order to produce a neuropathic cancer pain model, S-180 sarcoma cells were inoculated around the sciatic nerve of left legs of Balb/c mice. Magnetic Resonance Imaging (MRI) scanning confirmed the mass of S-180 cancer cells embedded around the sciatic nerve. Mechanical allodynia was most consistently induced in the mouse sarcoma cell line S-180 (2 x 10(6)sarcoma cells)-treated group compared to all the other groups studied. EA stimulation (2 Hz) was administered daily to ST36 (Zusanli) of S-180 bearing mice for 30 min for 9 days after S-180 inoculation. RESULTS: EA treatment significantly prolonged paw withdrawal latency from 5 days after inoculation. It also shortened the cumulative lifting duration from 7 days after inoculation, compared to the tumor control. Also, the overexpression of pain peptide substance P in the dorsal horn of the spinal cord was significantly decreased in the EA-treated group compared to the tumor control on Day 9 post inoculation. Furthermore, EA treatment effectively increased the concentration of beta-endorphin in blood and brain samples of the mice to a greater extent than that of the tumor control as well as the normal group. The concentration of beta-endorphin for EA treatment group increased by 51.457% in the blood and 12.6% in the brain respectively, compared to the tumor control group. CONCLUSION: The findings of this study suggest that a S-180 cancer pain model is useful as a consistent and short time animal model. It also indicated that EA treatment could be used as an alternative therapeutic method for cancer pain due to a consequent decrease in substance P and increase in beta-endorphin levels."

Evidence Sentence: Substance P and beta-endorphin mediate electro-acupuncture induced analgesia in mouse cancer pain model
Evidence Sentence: Furthermore, EA treatment effectively increased the concentration of beta-endorphin in blood and brain samples of the mice to a greater extent than that of the tumor control as well as the normal group.
Evidence Sentence: The concentration of beta-endorphin for EA treatment group increased by 51.457% in the blood and 12.6% in the brain respectively, compared to the tumor control group.
Evidence Sentence: It also indicated that EA treatment could be used as an alternative therapeutic method for cancer pain due to a consequent decrease in substance P and increase in beta-endorphin levels.
Evidence Sentence: To elucidate its analgesic mechanism, the levels of beta-endorphin in blood and brain tissues of mice were analyzed after EA treatment.
Evidence Sentence: 4B, the level of beta-endorphin in blood samples of the tumor control group was significantly increased up to 2.8754 +- 0.0278 ng/mL compared to that of the normal group, 1.3236 +- 0.0041.
Evidence Sentence: On the contrary, EA treatment significantly increased the beta-endorphin levels up to 4.355 +- 0.2972 ng/mL more than the tumor control group, 2.8754 +- 0.0278 ng/mL.
Evidence Sentence: 4C, the level of beta-endorphin in the brain tissues of mice within the tumor control group was significantly increased up to 4.0115 +- 0.3848 ng/mL compared to that of the normal group, 2.668 +- 1.069 ng/mL.
Evidence Sentence: In contrast, EA treatment significantly increased the level of beta-endorphin up to 9.0847 +- 0.5901 ng/mL more than that of the tumor control group, 4.0115 +- 0.3848 ng/mL.