Indirect Moxibustion (CV4 and CV8) Ameliorates Chronic Fatigue: A Randomized,Double-Blind,Controlled Study

Abstract

Objectives:

The antifatigue effect of indirect moxibustion and its antioxidant properties were investigated.

Subjects and design:

A randomized, double-blind, controlled clinical trial was performed with 44 patients who had idiopathic chronic fatigue. The subjects were treated with a placebo or moxibustion (indirect moxibustion on CV4 and CV8 3 times per week for 4 weeks), and their fatigue severity was monitored using a self-rating numeric scale (NRS) and a visual analog scale (VAS). Serum level of reactive oxygen species and malondialdehyde (MDA), total antioxidant capacity, the activity of catalase, superoxide dismutase, glutathione peroxidase, and glutathione reductase and total glutathione content, were determined before initial moxibustion therapy and after the 12th moxibustion treatment.

Results:

The moxibustion group had a significantly lower fatigue severity score compared to the control for both the NRS (p<0.05) and VAS scores (p<0.01). The level of serum MDA was significantly lower in the moxibustion group than in the placebo group (p<0.05), whereas glutathione reductase activity and total glutathione content increased significantly following moxibustion (p<0.05).

Conclusions:

The results provide clinical evidence for an antifatigue effect of indirect moxibustion at CV4 and CV8 and suggest that the effect is due to the antioxidant properties of moxibustion.

Introduction

C hronic fatigue is a subjective symptom when patients complain of feeling exhausted or lethargic for more than 6 months. Patients with chronic fatigue are faced with a pathogenic status regarding physical, social, and occupational well-being.¹ In particular, medically unexplained chronic fatigue, idiopathic chronic fatigue (ICF), and chronic fatigue syndrome (CFS) are agonizing illnesses due to severe impairment of quality of life and lack of effective therapies.² Thus, patients suffering from ICF or CFS frequently use alternative and complementary therapies.^3,4

Traditional Oriental medicine considers chronic fatigue to be the result of an unbalanced state among interfunctioning organs, or a deficient vital energy (called qi) condition with characteristic blood symptoms.⁵ Several clinical studies have shown positive results of herbal remedies on CFS,^6
–8 and acupuncture and moxibustion therapy have been leading treatments in traditional Oriental medicine. In particular, moxibustion treatment is effective for chronic disorders and deficient symptoms because it provides warm energy, expels Cold-Damp Stagnation, and enhances immunity.⁹

On the other hand, oxidative stress is an important element in the prevention or pathogenesis of various disorders including inflammation, cancer, and aging, and the antioxidant effects of many therapies or remedies have been well demonstrated.^10,11 Chronic fatigue is also linked to oxidative stress, and antioxidants have shown antifatigue effects in several clinical studies.^12,13 One (1) animal study showed an antioxidant effect of moxibustion pretreatment in a global brain ischemia rat model.¹⁴

The above therapeutic characteristics of moxibustion treatment are believed to be effective for chronic fatigue. The Chronic Fatigue Care Center at Daejeon Oriental Hospital in South Korea has applied indirect moxibustion at CV4 (Guanyuan) and CV8 (Shenque) for treating patients with ICF and CFS since 2006. To avoid skin burn, indirect moxibustion with salt-partition has generally been applied instead of direct moxibustion. These two acupoints (CV4 and CV8) have been frequently chosen to give moxibustion therapy for diverse disorders including fatigue-associated symptoms in clinics.¹⁵ To date, only a limited number of reports exist on the antifatigue effects of moxibustion,^16,17 and a randomized controlled clinical trial had not been conducted.

To investigate the link between moxibustion and treatment of chronic fatigue, the antifatigue effect of indirect moxibustion (CV4 and CV8) is herein evaluated, and the serum levels of biomarkers associated with oxidative stress and the antioxidant system are examined to explain the mechanisms.

Materials and Methods

Subjects

Adults who had experienced a feeling of fatigue for longer than 6 months, but who were not working at night, did not use alcohol, smoke, take medication, and who were not severely overweight (body mass index >30) were recruited. A physician and radiologist conducted examinations and excluded subjects who had abnormalities on hematological or radiological tests, or a history of psychiatric disorders (depression or anxiety). Of those recruited, 45 subjects (10 men and 35 women) were enrolled (median age, 44 years; range, 32−63 years). Subjects were allocated into either a moxibustion group (5 men and 20 women, median age, 44 years) or a control group (5 men and 15 women, median age, 45 years) by block randomization. Informed consent was obtained from each subject, and the Ethics Committee of Daejeon University Hospital, Republic of Korea, approved the study protocol (authorization number: DJOMC-36).

Study design and moxibustion treatment

A licensed doctor performed moxibustion at two acupoints on the conception vessel meridian, CV4 (located 3 cm below the center of the umbilicus) and CV8 (located at the center of the umbilicus), 3 times per week for 4 weeks throughout the trial. One (1) moxibustion treatment was defined as burning a moxa corn for 30 minutes with the patient lying on his or her back. A moxa corn consists of 3.5 g of wormwood fiber on the top of a salt basement inside bamboo; diameter: 30 mm, length: 40 mm (KyeGoo Inc., Incheon, South Korea, Fig. 1A). For placebo moxibustion, the moxa corn was inserted with thermal insulator composed of Styrofoam™ (rigid polystyrene plastic) and mudpack (Fig. 1B). A placebo moxibustion (thermal insulator inserted) was used in the control group (Fig. 1B). An infrared lamp was applied to maintain warmth in the abdominal area of patients in both groups. Fatigue severity was assessed by a self-numerical rating scale (NRS) and a visual analog scale (VAS) at 0, 2, and 4 weeks into the trial, and serum levels of biomarkers associated with oxidative stress and the antioxidant system were measured at 0 and 4 weeks using peripheral blood after a 12-hour fast.

FIG. 1.

Moxibustion treatment and moxa. Moxibustion was performed at CV4 and CV8 3 times per week for 4 weeks (A). One moxa consisted of 3.5 g of wormwood fiber inside bamboo with a salt basement (B).

Assessment of fatigue severity using the NRS and VAS

To measure the change in fatigue severity, a NRS was used with the Korean-translated Chalder Fatigue Severity questionnaire.¹⁸ The survey consisted of seven health-related physical questions and four mental health–related questions as follows:

1. How tired do you feel?

2. How strongly do you currently feel the need to rest?

3. How sleepy or drowsy do you feel?

4. Do you have problems starting things?

5. Do you lack energy?

6. Do you have less muscle strength?

7. Do you feel weak?

8. Do you have difficulty concentrating?

9. Do you have problems thinking clearly?

10. Do you make slips of the tongue when speaking?

11. How is your memory?

All subjects scored each item on a 10-point scale (0=not at all to 9=unbearably severe condition). Additionally, patients were asked to indicate their feelings of general fatigue by drawing a vertical line on a 10-cm VAS.

Determination of total reactive oxygen species

Serum reactive oxygen species (ROS) levels were determined according to Hayashi et al.¹⁹ Briefly, H₂O₂ was used as a standard to generate a calibration curve; N,N-diethyl-para-phenylenediamine (DEPPD) and ferrous sulfate solutions were prepared beforehand. Five microliters (5 μL) of standard solution or serum was added to 140 μL of 0.1 mol/L sodium acetate buffer (pH 4.8) in 96-well plates and incubated at 37°C for 5 minutes. One hundred microliters (100 μL) of DEPPD and ferrous mixture solution was added to each well, and the ROS levels were determined at 505 nm using a spectrophotometer.

Determination of lipid peroxide as malondialdehyde

Serum lipid peroxide levels were determined using thiobarbituric acid reactive substances (TBARS), as described by Kamal et al.²⁰ TBARS concentration was expressed as micromoles per liter malondialdehyde (MDA) in serum. Briefly, 250 μL of serum or standard solution was added to 2.5 mL of 20% trichloroacetic acid. This was mixed with 1 mL of 0.67% thiobarbituric acid and heated at 100°C for 30 minutes, followed by cooling on ice and vigorous vortexing with 4 mL n-butanol. After centrifugation at 3000×g for 20 minutes, the absorbance of the upper organic layer was measured at 535 nm with a spectrophotometer and compared to a 1,1,3,3-tetraethoxypropane standard curve.

Determination of total antioxidant capacity

Total antioxidant capacity (TAC) was determined according to Kambayashi et al.²¹ Ninety microliters (90 μL) of 10 mmol/L phosphate-buffered saline (pH 7.2), 50 μL of myoglobin solution (18 μmol/L), 20 μL of 3 mmol/L 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt solution, 20 μL of diluted serum sample, and various concentrations of gallic acid were added to a 96-well microplate and mixed well at 25°C for 3 minutes. Then, 20 μL of H₂O₂ was added to each well and incubated for 5 minutes. The absorbance was measured using a plate reader (Molecular Device Corp., Sunnyvale, CA) at 600 nm. TAC was expressed as gallic acid equivalent antioxidant capacity.

Determination of catalase and superoxide dismutase

Serum catalase activity was determined using the method of Beers and Sizer.²² Briefly, 100 μL of diluted serum or standard solution was mixed with 2.9 mL of substrate solution (0.0036% [w/w] H₂O₂ in 50 mmol/L potassium phosphate), followed by absorbance readings at 240 nm after 5 minutes. Serum superoxide dismutase (SOD) activity was determined using a SOD assay kit (Dojindo Laboratories, Kumamoto, Japan) according to the manufacturer's protocol. Bovine erythrocyte SOD was used as the standard.

Determination of total glutathione content, and activities of glutathione peroxidase and glutathione reductase

Glutathione (GSH) content was determined according to Ellman.²³ Briefly, 50 μL of diluted serum (in 10 mmol/L phosphate-buffered saline, pH 7.2) or GSH standard was combined with 80 μL of 5,5-dithiobis-(2-nitrobenzoic acid) (DTNB)/nicotinamide adenine dinucleotide phosphate (NADPH) mixture (10 μL of 4 mmol/L DTNB and 70 μL of 0.3 mmol/L NADPH) in a 96-well microplate. Next, 20 μL (0.06 U) of glutathione reductase (GSH-Rd) solution was added to each well, and the absorbance was measured using a plate reader at 405 nm.

Glutathione peroxidase (GSH-Px) activity was determined according to the method of Paglia and Valentine.²⁴ Briefly, 50 μL of NADPH reagent (5 mmol/L NADPH, 42 mmol/L GSH, 10 U/mL of GSH-reductase in 1.25 mL of distilled water) was added to 890 μL of GSH-Px buffer (50 mmol/L Tris-HCl [pH 8.0], 0.5 mmol/L EDTA). Then, 50 μL of serum sample and 10 μL of 30 mmol/L tert-butyl hydroperoxide solution were added to the mixture. The final absorbance was measured at 340 nm using an ultraviolet-visible spectrophotometer (Varian; Agilent Technologies, Santa Clara, CA).

GSH-Rd activity was determined according to a slightly modified method of Worthington and Rosemeyer.²⁵ Briefly, 150 μL of glutathione disulfide (GSSG) with 30 μL of GSH-Rd assay buffer (100 mmol/L potassium phosphate buffer [pH 7.5] with 1 mmol/L EDTA) was added to 30 μL of serum sample and diluted with GSH-Rd dilution buffer (100 mmol/L potassium phosphate buffer [pH 7.5] with 1 mmol/L EDTA and 1 mg/mL bovine serum albumin). Then, 75 μL of DTNB and 2 mmol/L NADPH were added, and the absorbance was read at 412 nm.

Statistical analysis

Statistical comparisons of the changed values between the placebo and moxibustion groups were analyzed using Student's t-test with the PASW Statistics 17 program (SPSS, Inc., Chicago, IL). Statistical significance was fixed at p<0.05.

Results

Change in fatigue severity as determined by the NRS

The initial NRS scores (mean±standard deviation) were 59.4±15.4 and 59.2±14.9 in the control and moxibustion groups, respectively. The total score for the 11 NRS questions decreased in both the control and moxibustion groups, but fatigue severity in the moxibustion group (14.3±12.4) was significantly ameliorated compared to that in the control group (4.3±16.3) during the 4-week trial (p<0.05; Fig. 2A). At the 2-week time point, the improved value did not reach statistical significance. In the analysis of subtotal NRS scores for physical (questions 1–7) and mental health (questions 8–11), moxibustion treatment significantly (p<0.05) improved physical fatigue symptoms from 39.3±9.7 to 32.6±6.4 after the 4-week trial compared to those in the control group (39.4±9.7 to 36.9±5.9; Fig. 2B). The 4-week moxibustion treatment also reduced the mental score from 19.9±7.0 to 15.4±5.1 compared to that in the control group (20.0±10.9 to 18.3±5.0) (p<0.05; Fig. 2C). For both physical and mental fatigue symptoms, the changed scores were not significant after 2 weeks of treatment.

FIG. 2.

Change in fatigue scores measured by the numerical rating scale (NRS) and visual analog scale (VAS). This figure shows the changes in fatigue severity between before and after (at 2 and 4 weeks, respectively) moxibustion. (A) Sum of the scores measured by a questionnaire-based NRS. (B) NRS physical fatigue subtotals score. (C) NRS mental fatigue subtotals score. (D) Average of the collective feelings of fatigue measured by the VAS. Values are expressed as the mean±standard deviation; *p<0.05 and **p<0.01 compared to control.

Change in fatigue severity as determined by the VAS

The initial VAS scores in the control and moxibustion groups were 6.7±0.8 and 6.9±1.5, respectively. Moxibustion treatment reduced the VAS score gradually by 5.2±1.8 during the 4-week moxibustion treatment, whereas that of the control group decreased by 6.3±1.0. A comparison of the changed scores between the control and moxibustion groups was significant after the 4-week time point (p<0.01) but not at the 2-week time point (Fig. 2D).

Changes in serum oxidative stress biomarkers, ROS and MDA

Serum total ROS levels were slightly decreased in both control and moxibustion groups, but were not statistically significant (p>0.05). Serum MDA level was decreased significantly following the 4-week moxibustion treatment compared to that in the control group (p<0.01, Table 1).

Table 1.

Changes in Antioxidant Activity After 4 Weeks with Moxibustion Treatment in the Serum Levels

	Placebo			Moxibustion
Measures	Before	After	Changed value	Before	After	Changed value	p-Value ^*
Total ROS (units)	162.9±39.7	149±35	−12.4±49.4	186±38.9	173±18.5	−14.5±32.6	0.874
MDA (μmol/L)	18.5±3.6	16.8±3.8	−1.5±2.9	19.4±3.1	15.2±3.1	−4.2±4.7	0.021^*
Total antioxidant capacity (μmol/L)	240.6±17.7	237.2±21.6	−2.7±29.1	222.2±24.9	227.7±22.3	4.5±35.3	0.487
Total GSH contents(μmol/L)	35.2±5.6	24.6±4	−11.2±8.3	36.7±11.6	44.8±5.6	8.1±10.2	0.001^**
GSH-peroxidase (U/mL)	0.3±1.2	0.2±0.4	0.1±1.1	0.1±1.3	0.1±1.0	0.1±1.0	0.735
GSH-reductase (U/mL)	0.1±0.1	0.1±0.1	0.01±0.06	0.1±0.1	0.2±0.1	0.1±0.1	0.012^*
Catalase activity (U/mL)	424.4±366.6	586.2±465	161.8±126.7	535±567	831.5±1095.6	269.5±514	0.340
Superoxide dismutase (U/mL)	2.0±0.4	3.3±0.8	1.3±1.3	1.9±0.5	3.6±1.8	1.7±1.6	0.406

Values are expressed as the mean–standard deviation.

p<0.05; ^** p<0.01 compared to control.

ROS, reactive oxygen species; MDA, malondialdehyde; GSH, glutathione reductase.

Changes in serum antioxidant system biomarkers, GSH content, and activities of TAC, SOD, GSH-Px, and GSH-Rd

The value of TAC was not altered by 4-week moxibustion as well as placebo moxibustion. In contrast, the 4-week moxibustion significantly increased serum levels of total GSH content (p<0.01) and GSH-Rx activity (p<0.05) compared to those in the control group. No significant changes were observed in GSH-Px and catalase activities between control and moxibustion groups (p>0.05, Table 1).

Discussion

Chronic fatigue is very prevalent, as nearly 10% of the general population has reported feeling fatigue worldwide.^26,27 One (1) study reported that 20% of visitors with chronic fatigue to eight Korean primary family clinics had no explained medical causes.²⁸ Medically unexplained chronic fatigue such as ICF and CFS are frequently problematic because of the lack of etiology and pathophysiologic mechanisms.²⁹ Despite this high morbidity of unexplained chronic fatigue, no standard treatment has been defined in conventional medicine. Accordingly, chronic fatigue is one of the most common complaints treated by alternative complementary therapies in the United States.³

In this study, the antifatigue effect of moxibustion on 44 subjects with ICF was investigated. This study was not targeted toward CFS, which can be diagnosed by typical criteria and has more severe symptoms than those of ICF.³⁰ The prevalence of ICF is reportedly 10 times higher than that of CFS. Among general U.S. populations, 4.2% of subjects have ICF and 0.42% of subjects suffer from CFS.³¹ The fatigue severity of subjects was about 60% of maximum (indicating unbearably severe status, 99 points on the total NRS score), and no difference was observed between the control and moxibustion groups (59.4±15.4 versus 59.2±14.9, respectively). These fatigue scores were more than twofold greater than those of healthy subjects measured with the same instrument (data not shown). Indirect moxibustion at CV4 and CV8 for 4 weeks gradually lowed the total NRS score by about 81% from the initial fatigue condition (from 59.4±15.4 to 48.1±9.6; Fig. 2A), and this antifatigue effect was more definite in the VAS score by 75% of the initial feeling (from 6.9±1. 5 to 5.2±1.8; Fig. 2D). Compared to the NRS, the VAS is thought to represent a more comprehensive assessment of fatigue because it is non-numeric.

Both physical and mental fatigue symptoms were ameliorated significantly by moxibustion at CV4 and CV8 but not by placebo moxibustion. Patients with chronic fatigue often complain of hyperalgesia and problems with concentration, memory, or sleep.^32,33 Some animal studies have shown that chronic indirect moxibustion releases visceral hyperalgesia.^34,35 One (1) study showed improvements in learning and memory in patients with vascular dementia following moxibustion on head-points.³⁶ In traditional Oriental medicine, moxibustion is generally thought to be preferable as a preventive therapy compared to acupuncture.³⁷ However, there is “limited evidence” that moxibustion is useful for patients with disease conditions including the fatigue symptom, and the underlying mechanism of moxibustion.

On the basis of the association of oxidative stress with chronic fatigue, serum biomarkers associated with oxidative stress and antioxidant defense system were examined. ROS are key oxidative stressors, and MDA is a general quantitative maker of lipid peroxidation by ROS.³⁸ Oxidative stressors are normally eliminated by various antioxidant mechanisms, including free-radical scavengers, catalase, SOD, and the glutathione oxidation/reduction systems.^39,40 One (1) study showed that the blood concentration of peroxide is significantly higher in patients with CFS than in normal controls.⁴¹ In the current results, serum MDA levels decreased significantly following indirect moxibustion compared to those in a placebo moxibustion control group. Additionally, 4-week moxibustion significantly increased serum levels of total GSH content and GSH-Rx activity (Table 1). Other antioxidant parameters such as TAC, SOD, and GSH-Px did not change significantly following moxibustion treatment. To date, no clinical study has reported an antioxidant effect of moxibustion. Only one animal study showed an antioxidant effect of moxibustion pretreatment in a global brain ischemia rat model through modulation of the SOD and MDA enzymes.¹⁴ The current data proposed that modification of antioxidant activity may be a possible mechanism for the antifatigue effect of moxibustion. However, the mechanisms of moxibustion may involve the neuroimmune modulation, circulation improvement, muscle relaxation, and changes of cytokine production.^42,43

Treatment effects can differ according to method, strength, duration, or location of moxibustion or acupuncture stimulation. In this study, subjects were treated with indirect moxibustion using salt-partitioned at CV4 and CV8. The CV4 and CV8 acupoints used in this study are traditionally believed to help immune function, and have been frequently chosen to apply moxibustion treatment for diverse fatigue-associated disorders.¹⁵ One (1) clinical study has shown the therapeutic effect of indirect moxibustion at CV4 and CV8 on primary dysmenorrhea of Cold-Damp type.⁴⁴ Also, two studies have shown immune-modulating effects of moxibustion at these acupoints, such as changes in serum interleukin-12 levels and natural-killer cell activity.^45,46

Forty-five (45) participants tested for all clinical procedures including blood sampling took part in this study. This study does not fall under the category of completely blind clinical study due to sensorial differences between the control group and the active moxibustion group.⁴⁷ At the end of the trial, some participants speculated that the treatment was real moxibustion: 1 of the control group and 8 of the moxibustion group. This may affect the subjective feeling of their fatigue symptom. Therefore, this may be a weakness of the study results. Another limitation is the lack of follow-up on fatigue levels.

Conclusions

Taken together, this study provides the first evidence of an antifatigue effect of repeated-indirect moxibustion at CV4 and CV8 in patients suffering from chronic fatigue. Further studies are needed to investigate the application and underlying mechanisms of moxibustion to treat patients with CFS in multicenter trials.

Footnotes

Acknowledgments

This study was supported by a grant from the Oriental Medicine R&D Project (B080043), Ministry of Health and Welfare, Republic of Korea.

Disclosure Statement

The authors declare that no competing financial interests exist.

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