Research on Acupuncture-moxibustion for Dry Eye Syndrome

Zhang Cui-hong, Zhang Lin-lin, Ma Xiao-peng, Yang Ling, Hong Jue, Liu Jie, Wu Ling-xiang

1 Shanghai Research Institute of Acupuncture and Meridian, Shanghai 200030, China

2 Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China

Research on Acupuncture-moxibustion for Dry Eye Syndrome

Zhang Cui-hong1, Zhang Lin-lin2, Ma Xiao-peng1, Yang Ling2, Hong Jue1, Liu Jie1, Wu Ling-xiang1

1 Shanghai Research Institute of Acupuncture and Meridian, Shanghai 200030, China

2 Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China

Dry eye syndrome (DES) is a commonly encountered ophthalmological disease, with a relatively high incidence, and expects an effective treatment method. Acupuncture-moxibustion therapy promotes tear production of lacrimal gland without causing a trauma, and thus has a great advantage in treating DES. Through literature analysis, this article summarized the research progress in both clinical practice and mechanism of acupuncturemoxibustion in treating DES during the recent 10 years, for providing valuable references for the application of acupuncture-moxibustion for DES.

Dry Eye Syndromes; Acupuncture Therapy; Moxibustion Therapy; Electroacupuncture; Acupuncture Medication Combined; Review

Dry eye syndrome (DES), also called keratoconjunctivitis sicca (KCS), refers to a group of ocular diseases characterized by damages to ocular surface, which are caused by abnormal tear production or tear film instability due to insufficient tear secretion or other reasons[1-2]. DES is currently the most commonly encountered ocular surface disease, and its major symptoms are eye dryness, sandy-gritty eye irritation, burning sensation, itchiness, and blurred vision, etc. Long-term disease may cause decreased transparency of cornea and vision, subsequently affecting work, study, and life, and even leading to vision loss. With the popularization of computer and altered life styles, DES is having a higher and higher incidence and tending to threaten younger ages. A Chinese epidemiological study on DES showed that the incidence has approached to 12.9%[3]. How to effectively manage DES has become a research highlight[4]. Acupuncture-moxibustion therapy can regulate the general body function, promote blood circulation around eyes, increase tear production, and thus can enhance the secretion of tears and improve DES symptoms from the root, and therefore has been more frequently used in the treatment of DES in clinic. This article summarized the research progress of acupuncture-moxibustion therapy in treating DES during the recent 10 years, for providing beneficial references for the acupuncturemoxibustion treatment for DES.

1 Clinical Research

The currently used acupuncture-moxibustion therapy for DES mainly covers acupuncture, electroacupuncture, moxibustion, combination of acupuncture and moxibustion, and combination of acupuncture-moxibustion and medication. Of them, acupuncture is used the most frequently; regarding acupoints selection, there are topical acupoints selection, distal acupoints selection, and acupoints selection based on syndrome differentiation, etc.

1.1 Acupuncture

There are clinical reports of acupuncture in treating DES both at home and abroad. Most of them are about acupuncture method by selecting topical acupoints plus distal acupoints. Gong L, et al[5]adopted acupuncture to treat 20 cases of DES and compared it with an artificial tears group of 24 cases. In the acupuncture group, Jingming (BL 1), Cuanzhu (BL 2), Yangbai (GB 14), Sizhukong (TE 23), Taiyang (EX-HN 5), Sibai (ST 2), Hegu (LI 4), Taichong (LR 3), Guangming (GB 37), Sanyinjiao (SP 6), and Fengchi (GB 20) were selected. The treatment was given once every other day with needles retained for 20 min each time, and 10 sessions constituted a treatment course. In 1 h after treatment, the total effective rate was 45% in the acupuncture group versus 50% in the control group, and the difference was statistically insignificant. In 3 weeks after treatment, the total effective rate was 40% in the acupuncture group versus 5% in the artificial tears group, and the difference was statistically significant. There was no adverse event in the acupuncture group but 2 adverse events happened in the control group. Gr?nlund MA, et al[6]randomized 25 KCS patients into an acupuncture group and a control group. In the acupuncture group, Sibai (ST 2), Touwei (ST 8), Zusanli (ST 36), Tongziliao (GB 1), Yangbai (GB 14), Cuanzhu (BL 2), and Hegu (LI 4) were selected. The control group was treated with artificial tears. After treatment, 6 cases in the acupuncture group were improved, and no exacerbation was revealed. In the control group, instead of any improvement, 2 cases were exacerbated. The first follow-up study revealed that acupuncture group had milder symptoms compared to the control group. Zhu GJ[7]treated 20 KCS subjects with Shuigou (GV 26) and Fengchi (GB 20) as the major acupoints and Jingming (BL 1), Houxi (SI 3), Sanyinjiao (SP 6), Yinlingquan (SP 9), and Taixi (KI 3) on the affected side as well as Hegu (LI 4) on the healthy side as the adjunct acupoints. Shuigou (GV 26) was inserted by a filiform needle of 40 mm in length towards nasal septum, with lifting-thrusting and twirling manipulations to produce sour hot swollen feelings. The treatment was given once every other day, and the needle was not retained. When Fengchi (GB 20) was punctured, the needle tip should be towards the contralateral orbit, making sour swollen sensation radiate to eyes. Even reinforcingreducing manipulations were applied to the adjunct acupoints, and the needles were retained for 0.5 h after needling sensation was obtained. The treatment was given once a day, with an interval at weekends, and 4-week treatment as a course. After a treatment course, indexes were improved and the total effective rate was 95.0%.

Regarding acupoints selection, some scholars compared the therapeutic effects between acupoints selection based on syndrome differentiation and topical acupoints selection. Wang ZL, et al[8]believe that acupuncture based on syndrome differentiation should be better than acupuncture by selecting topical acupoints. They observed 45 DES patients in total by randomizing them into three groups: a syndrome differentiation group (acupuncture group 1), a topical acupoints-selection group (acupuncture group 2), and an artificial tears group (control group). Acupuncture group 1 was intervened by acupuncture based on syndrome differentiation: for yin damage due to extreme heat, Quchi (LI 11), Hegu (LI 4), Sanyinjiao (SP 6), Taixi (KI 3), Yingxiang (LI 20), and Sibai (ST 2) were selected, and Zhaohai (KI 6) and Daling (PC 7) were added for insomnia; for retention of phlegm and stasis, Xuehai (SP 10), Yinlingquan (SP 9), Zusanli (ST 36), Fenglong (ST 40), Sanyinjiao (SP 6) and Sibai (ST 2) were selected, and Neiting (ST 44), Xingjian (LR 2), and Zulinqi (GB 41) were added for subjects with obvious heat symptoms (e.g. with dry mouth, fetid breath, red swelling eye lid, and yellow greasy tongue coating). In the acupuncture group 2, topical acupoints, including Cuanzhu (BL 2), Yangbai (GB 14), Sizhukong (TE 23), and Chengqi (ST 1), were punctured. The control group was intervened by artificial tear drops. For all the three groups, treatment was given once every other day, 10 sessions as a treatment course, and 3 courses in total. The total effective rate was 86.7% in the acupuncture group 1, 66.7% in the acupuncture group 2, and 33.3% in the control group, indicating that acupuncture based on syndrome differentiation has better effect than acupuncture with topical acupoints selection and artificial tears, and can enhance the therapeutic efficacy in treating DES. However, Gao WP, et al[9]have a different opinion that topical acupuncture should be better than acupuncture with general acupoints selection in extending tear film Break-up Time (BUT) and increasing tear production in climacteric DES. They divided DES patients into 3 groups. In group A (topical acupoints-selection group), Jingming (BL 1), Cuanzhu (BL 2), Sizhukong (TE 23), Tongziliao (GB 1), and Taiyang (EX-HN 5) were punctured. Group B was a general acupoints-selection group, and Ganshu (BL 18), Shenshu (BL 23), Sanyinjiao (SP 6), Taixi (KI 3), Fengchi (GB 20), Hegu (LI 4), and Zusanli (ST 36) were selected to receive acupuncture. In group A and group B, needles were retained for 30 min after needling sensation was obtained. Group C was intervened by eye drops. Four-week treatment was given in total for the three groups. The differences were statistically insignificant among the three groups in comparing the total effective rate. In comparing the extension of BUT and increase of tear production, group A was significantly different from group B and C (P＜0.05, P＜0.01); regarding the improvement of eyesymptom score, group A and B were both markedly superior to group C (P＜0.05). It indicates that topical acupuncture has comparatively better therapeutic effect in treating climacteric DES.

Besides, researchers also studied the involved factors which affect the therapeutic efficacy of acupuncture for DES, and found that the cause of the disease and age are both crucial factors. For example, Nepp J, et al[10]observed 102 subjects treated with acupuncture for 1 week, and found all indexes improved after acupuncture treatment. Acupuncture can produce a content effect in treating DES caused by external reasons, especially in treating DES caused by inflammation and disorders of autonomic nervous system, but the effect is unsatisfactory for Sj?gren DES. They also analyzed the relationship between age and therapeutic effect and discovered that the efficacy in young adults is better than that in patients aged over 50 years old.

1.2 Electroacupuncture

Electroacupuncture for DES has been less reported but its therapeutic effect has been verified. Liu YL, et al[11]adopted a randomized-controlled study method to confirm the effectiveness of electroacupuncture in treating DES. Forty subjects were randomized into a treatment group and a control group. The treatment group was intervened with electroacupuncture by selecting Jingming (BL 1), Taiyang (EX-HN 5), Cuanzhu (BL 2), Sizhukong (TE 23), Tongziliao (GB 1), and Fengchi (GB 20) as major acupoints, and Taixi (KI 3), Sanyinjiao (SP 6), and Taichong (LR 3) as adjunct acupoints. Bilateral Fengchi (GB 20) and Cuanzhu (BL 2) were connected to electroacupuncture apparatus, with frequency of 2 Hz and intensity within patient’s endurance. Needles were retained for 30 min, and 10 d as a treatment course. The control group was intervened by Sodium Hyaluronate (SH) eye drops. After 2 treatment courses, the total effective rate was 85.0% in the treatment group versus 63.2% in the control group. Electroacupuncture can increase tear production of DES patients and extend the BUT, and it has a better therapeutic effect compared to SH eye drops.

Does electroacupuncture enhance the therapeutic effect of acupuncture? Guo MH, et al[12]compared the therapeutic effect between electroacupuncture and ordinary acupuncture, by randomizing 47 DES patients into an acupuncture group (n=23) and an electroacupuncture group (n=24). In the acupuncture group, Shangjingming (Extra), Xiajingming (Extra), Tongziliao (GB 1), Cuanzhu (BL 2), Fengchi (GB 20), and Hegu (LI 4) were selected as major acupoints, and Sanyinjiao (SP 6), Taixi (KI 3), and Taichong (LR 3) were selected as adjunct acupoints. Needles were retained for 20 min after needling sensation was achieved. In the electroacupuncture group, with the same acupoints selection protocol and needling manipulations as in the acupuncture group, homolateral Tongziliao (GB 1) and Cuanzhu (BL 2) were connected as a pair to G6805-2 electroacupuncture apparatus after needling sensation was achieved, with continuous wave, frequency of 1.5 Hz, and intensity within patient’s endurance. For both groups, needles were retained for 20 min. The treatment was given by three times a week, and 12 sessions were given in total. It found that both groups had improvements in eye symptom score, Schirmer I Test (SIT), BUT, Corneal Fluorescein Staining (CFS), and Visual Analogue Scale (VAS) after treatment (P＜0.001). Compared to the acupuncture group, the electroacupuncture group had a significantly higher total effective rate (P＜0.05) and was better in improving eye symptom score and SIT (P＜0.05); the differences were insignificant between the two groups in comparing the improvements of VAS, BUT, and CFS (P＞0.05). However, this study had a rather small sample size. There still expects a large-sample study to further prove that electroacupuncture is better than ordinary acupuncture in treating DES. Moreover, how to select stimulus parameter is another acupoints requiring further study.

1.3 Moxibustion

Currently, among various moxibustion methods, thunder-fire moxibustion is the majorly used one for DES. Chen LQ[13]randomized 70 subjects with aqueous-deficient DES into two groups. Thirty-six subjects in the treatment group were treated with thunder-fire moxibustion by selecting Cuanzhu (BL 2), Yuyao (EX-HN 4), Tongziliao (GB 1), Taiyang (EX-HN 5), Sibai (ST 2), Jingming (BL 1), Ermen (TE 21), Yifeng (TE 17), and Hegu (LI 4). Initially, revolving moxibustion was applied to forehead for 2-3 min, then to eyes and periocular acupoints, 2-3 min for each eye, and finally to auricles. Ermen (TE 21), Yifeng (TE 17), ear lobules and bilateral Hegu (LI 4) were treated with bird-pecking moxibustion. The treatment was given once per day, 20 min for each session. The other 34 cases in the control group received eye drops for treatment. For both groups, 10-day treatment was considered as a course, and 2 courses were given in total. The results showed that the treatment group was better than the control group in improving subjective symptoms, SIT, BUT, and CFS (P＜0.05). Song L, et al[14]also adopted thunder-fire moxibustion to treat 20 DES patients, and found that it had a better result compared to SH eye drops. Ju S[15]treated 42 DES patients with thunder-fire moxibustion in addition to SH eye drops and achieved a total effective rate of 95.6%, which was better than the treatment with SH eye drops alone.

During the treatment with moxibustion, some DES patients find uncomfortable with the smoke produced by moxibustion. Therefore, we believe that the amelioration of moxibustion method will promote the application of moxibustion in treating DES.

1.4 Combination of acupuncture and moxibustion

As we see that both acupuncture and moxibustion are effective approaches for DES, then, can the combination of acupuncture and moxibustion enhance the therapeutic efficacy? Zhang YC, et al[16]observed the effect of acupuncture and thunder-fire moxibustion on tear film of DES patients, by selecting Baihui (GV 20), Jingming (BL 1), Cuanzhu (BL 2), Taiyang (EX-HN 5), Sibai (ST 2), Fengchi (GB 20), Hegu (LI 4), Zusanli (ST 36), Sanyinjiao (SP 6), Taixi (KI 3), and Taichong (LR 3). Qihai (CV 6) was added for deficiency of qi and yin; Waiguan (TE 5) and Fenglong (ST 40) were added for stagnation of dampness and heat; Xuehai (SP 10) and Quchi (LI 11) were added for stagnation of blood stasis. Even reinforcing-reducing manipulations were performed after needling sensation arrived. Needles were retained for 20 min. Thunder-fire moxibustion was conducted after acupuncture treatment. The treatment was given once a day, 10 sessions as a treatment course. After treatment, 30 subjects had their tear production and stability of tear film increased significantly. Wei LX, et al[17]treated 40 DES patients with acupuncture plus non-smoke moxibustion. Acupoints on head and face, such as Jingming (BL 1), Cuanzhu (BL 2), Taiyang (EX-HN 5), Sibai (ST 2), Baihui (GV 20), Shenting (GV 24), and Fengchi (GB 20), were selected; distal acupoints including Quchi (LI 11), Waiguan (TE 5), Hegu (LI 4), Zhongwan (CV 12), Tianshu (ST 25), Qihai (CV 6), Zusanli (ST 36), Sanyinjiao (SP 6), Taixi (KI 3), and Taichong (LR 3) were also selected. Needles were retained for 20 min. Non-smoke thunder-fire moxibustion was performed afterwards. The treatment was given once every other day, 10 times as a treatment course, and 20 courses were conducted in total. The total effective rate was 73.1%.

Although the aforementioned scholars observed the integrated therapeutic effect of acupuncture and moxibustion, none of them conducted a comparative study between pure acupuncture and pure moxibustion, and hence no evidence could show that the integrated use of acupuncture and moxibustion can enhance the therapeutic efficacy.

1.5 Acupuncture-moxibustion plus Chinese medication

To improve clinical efficacy, some researchers used acupuncture and Chinese medication together to treat DES, and it’s indeed effective. However, there still lacks of comparative studies to show that integrated use of acupuncture and Chinese medication has better therapeutic efficacy than acupuncture alone. Chinese medication is usually administered orally, via fumigation, or both together. Zhou PP, et al[18]treated 100 patients with secretion-deficient DES with acupuncture plus Chinese medication by dividing them into two groups. The treatment group was intervened by acupuncture and Chinese medication, and the control group was by eye drops. The result showed that the treatment group had a higher total effective rate than the control group. After treatment, the SIT, Schirmer II Test (SIIT), and BUT values in the treatment group were all increased and were significantly higher than those in the control group (P＜0.05). It indicates that combination of acupuncture and Chinese medication can promote the tear secretion of DES patients, which is possibly one of the action mechanisms of acupuncture and/or Chinese medication in treating DES. Liu XQ, et al[19]studied the therapeutic efficacy of acupuncture plus Chinese medication fumigation for DES by randomizing 90 subjects into a treatment group of 44 cases and a control group of 46 cases. The treatment group was intervened by acupuncture plus Chinese medication fumigation. The major acupoints were Chengqi (ST 1), Cuanzhu (BL 2), Jingming (BL 1), and Tongziliao (GB 1), and the adjunct acupoints were Fengchi (GB 20), Ganshu (BL 18), Shenshu (BL 23), and Taixi (KI 3). The fumigation formula was composed of Gou Qi (Fructus Lycii) 12 g, Ju Hua (Flos Chrysanthemi) 9 g, Qin Pi (Cortex Fraxini) 9 g, Gui Zhen Cao (Herba Bidentis Pilosae) 12 g, and Bing Pian (Borneolum) 0.3 g. The herbs were decocted with water and then packed at 30 mL. The 30 mL medicinal fluid was poured into the medicinal cup of the fumigation apparatus. When cold medicinal mist was produced, two eyes were fumigated simultaneously, 15 min for each time. Acupuncture and fumigation were both given once every other day, 30 d as a treatment course, and 3 courses were given totally. The control group was intervened by SH eye drops. The total effective rate was 78.4% in the treatment group versus 12.0% in the control group, and the difference was statistically significant (P＜0.01). Xie GF, et al[20]studied the clinical efficacy of acupuncture plus Qing Xuan Run Mu Yin (the decoction for clearing dizziness and moisturizing eyes) by both external and internal application, in treating DES. Patients were randomized into a treatment group and a control group. The treatment group was intervened by acupuncture plus Chinese medicinal fumigation followed by oral administration. Jingming (BL 1), Cuanzhu (BL 2), Sizhukong (TE 23), Sibai (ST 2), Baihui (GV 20), Taiyang (EX-HN 5), Shaoze (SI 11), Taichong (LR 3), and Zusanli (ST 36) were selected to receive acupuncture. The control group was treated with eye drops. The total effective rate was 91.7% in the treatment group, which wassignificantly better than those treated with eye drops alone (P＜0.05).

1.6 Other therapies

Besides the aforementioned major methods, other therapies such as acupoint injection, acupoint massage, and eye acupuncture have also been reported in the treatment of DES. Yin HR, et al[21]adopted acupoint injection to treat DES. They divided 75 subjects into a treatment group of 45 cases and a control group of 30 cases. The treatment group was managed by acupoint injection with Dang Gui (Radix Angelicae Sinensis) injection in addition to conventional ophthalmological treatment. For acupoint injection, bilateral Cuanzhu (BL 2), Sizhukong (TE 23), Taiyang (EX-HN 5), Sibai (ST 2), Hegu (LI 4), Fengchi (GB 20), Sanyinjiao (SP 6), Taichong (LR 3), and Zusanli (ST 36) were selected, 0.5 mL for each acupoint. The acupoints were treated alternately, once every day or once every other day. The control group received conventional ophthalmological treatment. For both groups, 10 d constituted a treatment course, and therapeutic efficacy was observed after 3 treatment courses. The total effective rate was 91.1% in the treatment group versus 73.3% in the control group, and the therapeutic efficacy in the treatment group was better than that in the control group (P＜0.05). It indicates that acupoint injection with Dang Gui (Radix Angelicae Sinensis) injection is an effective approach in treating DES. Hou SH[22]used acupoint massage together with eye drops in treating 200 subjects with DES of visual fatigue. Cuanzhu (BL 2), Jingming (BL 1), Shangming (Extra), Tongziliao (GB 1), Chengqi (ST 1), Sibai (ST 2), and Taiyang (EX-HN 5) were selected. It’s quite effective in treating patients with DES of visual fatigue. Eye acupuncture has also been reported in the treatment of DES[23].

2 Mechanism Research

Mechanism study on acupuncture-moxibustion for DES hasn’t fully developed and thus is rarely reported. The published researches were summarized as the following 3 aspects.

2.1 Improving morphology and function of lacrimal gland

When observing the morphology of lacrimal gland of DES rabbit, Zhang YB, et al[24]found that the morphology of lacrimal gland was obviously changed and cells were activated under both light and electronic microscopes. It suggests that acupuncture can improve the sensitivity of the nerve reflex, promote the lacrimal metabolism, and thus can increase the synthesis and secretion of tears of rabbit models. Gong L, et al[25-26]also discovered that acupuncture can ameliorate the ultrastructure of rabbit’s lacrimal gland and raise the content of vasoactive intestinal peptide (VIP) in lacrimal gland, and VIP directly interacts with secretory cells to stimulate gland to generate tears. Gao WP, et al[27]once determined the content of acetylcholine (Ach) in rabbit’s lacrimal gland, and found that acupuncture can increase the content of Ach, which potently stimulates lacrimal gland cells to produce proteins, water and electrolytes, and contributes to the production of tears through activating the action of muscarini receptor (receptor M).

2.2 Regulating apoptosis

After successfully establishing a neutered DES male rabbit model, Zhang YM, et al[28]evaluated the tear production and the expression of Fas and FasL, which are related to the apoptosis of epithelial cells of lacrimal gland. They found that topical acupuncture can enhance the tear secretion in nertered DES male rabbits, down-regulate the expression of Fas and FasL in epithelial cells of lacrimal gland, and subsequently inhibit the apoptosis of epithelium of lacrimal gland.

2.3 Regulating sex hormones

Decrease of sex hormones is a crucial factor resulting in the onset and development of DES. Of them, androgens can especially regulate the general and topical immune functions, modulate the morphology, development, differentiation and secretory functions of lacrimal gland and meibomian gland, and also play an important role in the regulation of the stability of tears, inflammation and cellular apoptosis. A research by Peng QH, et al[29]revealed that acupuncture can downregulate the over-expressed Estradiol (E2) and up-regulate the low Testosterone (T) level in peripheral blood circulation. It illuminates that acupuncture plays a bidirectional role in regulating sex hormones, which is possibly an important mechanism of acupuncturemoxibustion in treating DES.

3 Summary and Prospect

Clinical researches from both home and abroad provide rich clinical evidences for the superiority of acupuncture-moxibustion in treating DES. In traditional Chinese medicine, DES should be categorized into“Bai Se Zheng (xerosis conjunctivitis)”, “Zao Zheng (sicca syndrome)”, etc. It says in Huang Di Nei Jing (Yellow Emperor's Classic of Internal Medicine) that vision comes from the essence of Zang-fu organs. If there is a blockage in meridians and collaterals and qi and blood cannot go up to nourish eyes, there will appear dryness and discomfort of eyes. When peri-ocular acupoints are punctured, it can activate and unblock meridians and collaterals, regulate and harmonize qi and blood, remove blockage in orifices, balance yin and yang, promote the blood circulation around eyes, and finally relieve symptoms of DES[30-31].

In a word, acupuncture, electroacupuncture, moxibustion, combination of acupuncture and moxibustion, and combination of acupuncturemoxibustion and medication all can achieve a certain effect in treating DES. Clinical observations suggest that symptoms, body signs, and lab indexes can all be improved to some extent without any adverse effects, which reflect the advantage of acupuncture-moxibustion in treating DES. However, absence of rigorous and reasonable controls, scientific therapeutic evaluation standard, and long-term effect observation also brings uncertainty to the evaluation of therapeutic efficacy and makes it difficult to select a relatively better acupuncture-moxibustion therapy or acupoint formula. Therefore, there still expects randomized-controlled trials of high quality to further confirm the efficacy and safety of acupuncture-moxibustion in treating DES. Only by this way, can we explore an acupuncturemoxibustion therapy with more precise therapeutic efficacy and higher practicability, and provide reliable guiding evidence for future clinical practice[32]. Undoubtedly, multi-centered large-sample randomizedcontrolled trials in a scientific and rigorous manner should remain as the focus in future, as it helps the general recognition, further promotion and application of acupuncture-moxibustion in treating DES.

Experimental study on acupuncture-moxibustion for DES has just begun. Preliminary research has discovered that improving morphology and function of lacrimal gland, regulating cellular apoptosis and sex hormones are possibly the crucial action mechanisms of acupuncture-moxibusition in treating DES. But the pathogenesis of DES is involving multiple factors, such as inflammation, cellular spoptosis, immune dysfunction, abnormal nerve regulation, and disorders of sex hormones, of which, inflammation and apoptosis are regarded as the most important factors[33]. At present, there is a lack of reports on acupuncture-moxibustion for DES from the perspectives of inflammation and apoptosis. In the future, systemic studies should be conducted based on election of DES animal models proper for acupuncture-moxibustion studies and from the angels of inflammation and cellular apoptosis. NF-κB plays a potent role in regulating gene transcription of key factors in various diseases. Via target gene products, NF-κB signal pathway is involved in a variety of pathological processes including inflammation, cellular apoptosis, immune responses, as well as the modulation of cell cycle and cell differentiation[34-37]. Exploring the action mechanism of acupuncture-moxibustion for DES by considering the NF-κB signal pathway will be beneficial for the reveal of the molecular mechanism of the treatment and will provide scientific experimental evidences for the clinical application.

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Translator: Hong Jue

R246.82

A

Date: January 30, 2013

Author: Zhang Cui-hong, M.D., research assistant.

Ma Xiao-peng, M.D., researcher. E-mail: pengpengma@163.com