To understand moxibustion from the biological effect of local thermal stimulation

Temperature Characteristics of Traditional Indirect Moxibustion and Electronic Moxibustion

Background

Electronic moxibustion (EM) was developed to minimize the side effects of traditional moxibustion, such as burns, and to overcome therapeutic compliances such as smoke or smell.

Objectives

To investigate distributions and thermal stimulation of EM at various depths using silicon phantom and to compare this methodology to traditional indirect moxibustion (TIM).

Methods

A silicon phantom composed of polydimethylsiloxane was heated and immersed in a hot plate containing warm water to set the phantom's temperature to that of biological tissue. K-type thermocouples were inserted into the phantom at depths of 0, 2, 5, 7, and 10 mm to measure temperature changes with thermal stimulation of EM or TIM placed on top of the phantom.

Results

At the surface of the phantom, the peak temperature after applying TIM (55.04 ± 0.92℃ [Δ23.79 ± 0.96℃]) was significantly higher than after EM (43.25 ± 1.95℃ [Δ13.00 ± 2.23℃]), with both interventions reaching the highest temperature after 2 minutes. The temperature increase for TIM was also statistically significant compared to EM when measured at a depth of 2 mm. For the experimental setting with TIM, after reaching peak surface temperature, a rapid decrease was observed at the surface and 2 mm while EM showed a much more gradual decline. There was no significant difference in temperature change between the groups at depths of 5, 7, and 10 mm.

Conclusion

TIM resulted in a higher temperature rise compared to EM at the surface and at a 2 mm depth reaching over 50℃, which creates risk of burns. Thermal stimulation with EM had a lower risk of burns with temperature increment not being statistically different from TIM below the depth of 5 mm.

Mitochondrial Respiratory Chain and Its Regulatory Elements SIRT1 and SIRT3 Play Important Role in the Initial Process of Energy Conversion after Moxibustion at Local Skin

Objectives

To study how thermal energy is converted after moxibustion at local skin from the view of mitochondrial respiratory chain and its key regulatory elements of sirtuins 1 (SIRT1) and sirtuins 3 (SIRT3).

Methods

Two moxibustion temperatures usually used in clinical practice (38°C and 46°C) were applied to Zusanli (ST36) acupoint for 30 minutes in C57BL/6J mice. Local skin samples were harvested at 30 min and 72 h after moxibustion intervention, respectively. The activity of mitochondrial respiratory chain complexes I–V was detected by spectrophotometry. The expression of SIRT1 and SIRT3 protein was detected by immunofluorescence staining or western blot.

Results

Moxibustion at 38°C triggered more significant increase of mitochondrial respiratory chain complexes I–V expression. However, the protein expression of SIRT1 and SIRT3 at 46°C showed more obvious enhancement. In addition, the effect of mitochondrial respiratory chain complexes I–V activity on local skin of ST36 acupoint was more obvious at 30 min after moxibustion, while the expression of SIRT1 and SIRT3 protein was more significant at 72 h after moxibustion.

Conclusion

Mitochondrial respiratory chain and its key regulatory element proteins SIRT1 and SIRT3 play important role in the initial process of thermal energy conversion stimulated by different moxibustion temperatures in local skin.

Short-Term Efficacy of Pulsed Radiofrequency Thermal Stimulation on Acupoints for Chronic Low Back Pain: A Preliminary Study of a Randomized, Single-Blinded, Placebo-Controlled Trial

Background

The objective of this study was to evaluate the pain-relief efficacy of thermal stimulation induced by a pulsed radiofrequency (PRF) thermal stimulation applied to acupoints (APs) in patients with low back pain (LBP). The study was designed as a randomized, single-blinded, placebo-controlled trial. Methods. Fifty-six LBP patients whose minimum pain intensity score on a visual analogue scale (VAS, 0-100 mm) was more than 30 mm were randomly allocated to either the placebo-controlled or the treatment group at a 1:1 ratio. The treatment and placebo-controlled groups received PRF thermal stimulation plus cupping therapy and cupping therapy only, respectively. Each patient was scheduled to receive a total of three treatment sessions over one week with allowing a window up to 4 days. Six of the 13 predefined APs were selected differently for each session depending on the change in patient's symptoms and intensity of pain. The primary outcome was the mean difference between the placebo-controlled and treatment group of VAS changes from the baseline to the end of the follow-up period.

Results

The patients' reported VAS scores from baseline to the end of follow-up (average: 9.8 days) were significantly decreased by 8.036 points (two-sided 95% CI, -11.841 to -4.231) and 13.393 points (two-sided 95% CI: 17.198 to -9.588) in the treatment and the placebo-controlled groups, respectively. However, the change in VAS scores between the treatment group and the placebo-controlled group was not significantly different (2.015 mm, two-sided 95% CI: -5.288 to 9.317).

Conclusion

The trial results indicated that treatment with either PRF thermal stimulation with cupping therapy or cupping therapy alone effectively relieved LBP. The efficacy of PRF thermal stimulation combined with cupping therapy was not superior to that of cupping therapy alone. Trial registration number: Clinical Research Information Service (KCT0002137). The trial was registered retrospectively on 10 November, 2016.