Limits...
Substance P and beta-endorphin mediate electro-acupuncture induced analgesia in mouse cancer pain model.

Lee HJ, Lee JH, Lee EO, Lee HJ, Kim KH, Kim SH, Lee KS, Jung HJ, Kim SH - J. Exp. Clin. Cancer Res. (2009)

Bottom Line: 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.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.

View Article: PubMed Central - HTML - PubMed

Affiliation: College of Oriental Medicine, Kyung-Hee University, Seoul 130-701, South Korea. strong79@khu.ac.kr

ABSTRACT

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.

Show MeSH

Related in: MedlinePlus

A: MRI scans of S-180 tumor mass around the sciatic nerve. After inoculation of S-180 tumor cells around the sciatic nerve, MRI scan was performed. (a) On inoculation day (b) 10 days after inoculation (c) 16 days after inoculation (d) 24 days after inoculation. B: S-180 implantation around sciatic nerve-induced neuropathic cancer pain according to cell number in a time course study. Withdrawal latency of left hind paws was measured every 2 days until 17 days after inoculation. Values are expressed means ± SE. Statistically significant differences were recorded after comparison to the control using the student's t test (* p < 0.05, ** p < 0.01).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2724388&req=5

Figure 2: A: MRI scans of S-180 tumor mass around the sciatic nerve. After inoculation of S-180 tumor cells around the sciatic nerve, MRI scan was performed. (a) On inoculation day (b) 10 days after inoculation (c) 16 days after inoculation (d) 24 days after inoculation. B: S-180 implantation around sciatic nerve-induced neuropathic cancer pain according to cell number in a time course study. Withdrawal latency of left hind paws was measured every 2 days until 17 days after inoculation. Values are expressed means ± SE. Statistically significant differences were recorded after comparison to the control using the student's t test (* p < 0.05, ** p < 0.01).

Mentions: As shown in Fig. 2A, S-180 cells grow rapidly and embedded around the sciatic nerve in a time-dependent manner, which was confirmed by MRI scanning. On day 9 after inoculation, the sciatic nerve was partially embedded by an S-180 tumor mass and on day 24, the sciatic nerve was almost surrounded by the S-180 tumor mass. As shown in Fig. 2B, among the three groups studied (1 × 107, 5 × 106 and 2 × 106 injected groups), neuropathic cancer pain was most steadily induced in 2 × 106 injected group 2 days after inoculation, suggesting that the suitable cell number that induced neuropathic cancer pain was 2 × 106.


Substance P and beta-endorphin mediate electro-acupuncture induced analgesia in mouse cancer pain model.

Lee HJ, Lee JH, Lee EO, Lee HJ, Kim KH, Kim SH, Lee KS, Jung HJ, Kim SH - J. Exp. Clin. Cancer Res. (2009)

A: MRI scans of S-180 tumor mass around the sciatic nerve. After inoculation of S-180 tumor cells around the sciatic nerve, MRI scan was performed. (a) On inoculation day (b) 10 days after inoculation (c) 16 days after inoculation (d) 24 days after inoculation. B: S-180 implantation around sciatic nerve-induced neuropathic cancer pain according to cell number in a time course study. Withdrawal latency of left hind paws was measured every 2 days until 17 days after inoculation. Values are expressed means ± SE. Statistically significant differences were recorded after comparison to the control using the student's t test (* p < 0.05, ** p < 0.01).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2724388&req=5

Figure 2: A: MRI scans of S-180 tumor mass around the sciatic nerve. After inoculation of S-180 tumor cells around the sciatic nerve, MRI scan was performed. (a) On inoculation day (b) 10 days after inoculation (c) 16 days after inoculation (d) 24 days after inoculation. B: S-180 implantation around sciatic nerve-induced neuropathic cancer pain according to cell number in a time course study. Withdrawal latency of left hind paws was measured every 2 days until 17 days after inoculation. Values are expressed means ± SE. Statistically significant differences were recorded after comparison to the control using the student's t test (* p < 0.05, ** p < 0.01).
Mentions: As shown in Fig. 2A, S-180 cells grow rapidly and embedded around the sciatic nerve in a time-dependent manner, which was confirmed by MRI scanning. On day 9 after inoculation, the sciatic nerve was partially embedded by an S-180 tumor mass and on day 24, the sciatic nerve was almost surrounded by the S-180 tumor mass. As shown in Fig. 2B, among the three groups studied (1 × 107, 5 × 106 and 2 × 106 injected groups), neuropathic cancer pain was most steadily induced in 2 × 106 injected group 2 days after inoculation, suggesting that the suitable cell number that induced neuropathic cancer pain was 2 × 106.

Bottom Line: 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.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.

View Article: PubMed Central - HTML - PubMed

Affiliation: College of Oriental Medicine, Kyung-Hee University, Seoul 130-701, South Korea. strong79@khu.ac.kr

ABSTRACT

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.

Show MeSH
Related in: MedlinePlus