Effect of electro-acupuncture at different acupoints on neuropeptide and somatostatin in rat brain with irritable bowel syndrome. Chin J Integr Med. 2012;18:288-292. [PMID: 22457140 DOI: 10.1007/s11655-011-0795-y]

The efficacy and neural mechanism of acupuncture therapy in the treatment of visceral hypersensitivity in irritable bowel syndrome

Irritable Bowel Syndrome (IBS) is a complex functional gastrointestinal disorder primarily characterized by chronic abdominal pain, bloating, and altered bowel habits. Chronic abdominal pain caused by visceral Hypersensitivity (VH) is the main reason why patients with IBS seek medication. Significant research effort has been devoted to the efficacy of acupuncture as a non-drug alternative therapy for visceral-hyperalgesia-induced IBS. Herein, we examined the central and peripheral analgesic mechanisms of acupuncture in IBS treatment. Acupuncture can improve inflammation and relieve pain by reducing 5-hydroxytryptamine and 5-HT3A receptor expression and increasing 5-HT4 receptor expression in peripheral intestinal sensory endings. Moreover, acupuncture can also activate the transient receptor potential vanillin 1 channel, block the activity of intestinal glial cells, and reduce the secretion of local pain-related neurotransmitters, thereby weakening peripheral sensitization. Moreover, by inhibiting the activation of N-methyl-D-aspartate receptor ion channels in the dorsal horn of the spinal cord and anterior cingulate cortex or releasing opioids, acupuncture can block excessive stimulation of abnormal pain signals in the brain and spinal cord. It can also stimulate glial cells (through the P2X7 and prokinetic protein pathways) to block VH pain perception and cognition. Furthermore, acupuncture can regulate the emotional components of IBS by targeting hypothalamic-pituitary-adrenal axis-related hormones and neurotransmitters via relevant brain nuclei, hence improving the IBS-induced VH response. These findings provide a scientific basis for acupuncture as an effective clinical adjuvant therapy for IBS pain.

The Role of Acupuncture on the Gut-Brain-Microbiota Axis in Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a chronic dysfunction of the gastrointestinal tract, commonly characterized by abdominal pain or abdominal discomfort. These symptoms can substantially reduce the quality of life and work productivity of the patients. The exact pathogenesis of IBS remains unclear, as it has become apparent that multiple pathways are activated in the condition, including inflammation, immunology, neurology and psychology. Recent evidence has shown that symptoms in IBS are related to the dysfunction of the nervous system, particularly the viscerosomatic pathway, through immune-to-brain communication. The potential link between brain-gut relationships is gut microbiota. The management of IBS mostly focuses on symptomatically treating the patients. There are a wide range of standard treatments, including pharmacological to psychological interventions which are effective in some patients. Therefore, a combination of therapies including both standard and complimentary treatments, including Traditional Chinese Medicine (TCM) such as acupuncture, have been used in treating IBS patients. Several in vivo and clinical studies have demonstrated the efficacy of acupuncture in treating IBS. Increasing attention has been paid to research regarding the action mechanisms of acupuncture for IBS. This paper summarizes and discusses the possible mechanisms associated with acupuncture on the pathophysiology of IBS, including gastrointestinal (GI) motility, visceral hypersensitivity, the immune system, neurotransmitters, and the brain-gut axis. The results fromin vivo and clinical studies have been included. In addition, the effects of acupuncture on gut microbiota in IBS are included and any contradictory findings are deliberated.

Acupuncture-Analgesia-Mediated Alleviation of Central Sensitization

Pain can trigger central amplification called central sensitization, which ultimately results in hyperalgesia and/or allodynia. Many reports have showed acupuncture has an analgesic effect. We searched the related article on PubMed database and Cochrane database to discover central sensitization pathway in acupuncture analgesia. We summarized that acupuncture enhances the descending inhibitory effect and modulates the feeling of pain, thus modifying central sensitization. The possible mechanisms underlying the analgesic effects of acupuncture include segmental inhibition and the activation of the endogenous opioid, adrenergic, 5-hydroxytryptamine, and N-methyl-D-aspartic acid, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid/kainate pathways. Moreover, acupuncture can locally reduce the levels of inflammatory mediators. In clinical settings, acupuncture can be used to treat headache, neuropathic pain, low back pain, osteoarthritis, and irritable bowel syndrome. These mechanisms of acupuncture analgesia may be involved in the alleviation of central sensitization.

Changes in small intestinal motility and related hormones by acupuncture stimulation at Zusanli (ST 36) in mice

OBJECTIVES

To clarify the effects of acupuncture stimulation at Zusanli (ST 36) on the hormonal changes.

METHODS

Eight-week-old male C57BL/6 mice received acupuncture stimulation at acupoint ST 36 or Quchi (LI 11) once a day for 3 or 5 days in the acupuncture-stimulated groups, but not received in the normal group (n=6 in each group). On day 3 or 5, animals were given 0.1 mL of charcoal orally with a bulbed steel needle, 30 min after the last acupuncture stimulation. Ten minutes later, mice were anesthetized, and the intestinal transit and the concentrations of vasoactive intestinal peptide (VIP), motilin, ghrelin and gastrin in the serum were measured.

RESULTS

Compared to no acupuncture stimulation, acupuncture stimulation at ST 36 for 5 days increased the intestinal transit and down-regulated the concentration of VIP and up-regulated the concentrations of motilin, ghrelin and gastrin (P<0.05 or 0.01), whereas acupuncture stimulation at LI 11 did not change them signifificantly (P>0.05).

CONCLUSION

Acupuncture stimulation at ST 36 for 5 days enhances the small intestinal motility and regulates the secretion of hormones related to small intestinal motility.

Antinociceptive and antidiarrheal effects of pioglitazone in a rat model of diarrhoea-predominant irritable bowel syndrome: role of nitric oxide

Irritable bowel syndrome (IBS) is a prevalent disease characterized by abdominal pain and abnormal bowel habits. Pioglitazone is a peroxisome proliferator-activated receptor (PPAR) γ agonist and, although it is mostly used as an antidiabetic agent, it has been reported to have analgesic effects. Nitric oxide (NO), a gaseous molecule that mediates many of the effects of pioglitazone, has been implicated in the pathophysiology of IBS. The aim of the present study was to investigate the effects of pioglitazone on symptoms in a rat model of diarrhoea-predominant IBS (D-IBS).and to determine the role of NO in these effects. Diarrhoea-predominant IBS was induced by intracolonic instillation of acetic acid. Pioglitazone (2 mg/kg, i.p.) was administered on Days 7, 9 and 11 after acetic acid instillation. To investigate the mechanism involved in pioglitazone action, rats were also administered either the PPARγ antagonist GW9662 (3 mg/kg, i.p.), the NO synthase (NOS) inhibitor N(G) -nitro-l-arginine methyl ester (l-NAME; 10 mg/kg, i.p.) or the NO precursor l-arginine (250 mg/kg, i.p.) along with pioglitazone. Visceral hypersensitivity, nociceptive thresholds, defecation frequency, stool form, serum and colon NO production and inducible (i) NOS activity were assessed 1 h after the final injection of pioglitazone or dimethylsulphoxide (used as the vehicle). Pioglitazone reduced visceral hypersensitivity and defecation frequency, increased nociceptive thresholds, NO production and iNOS activity and shifted stool form towards hard stools in D-IBS rats. These effects of pioglitazone were significantly reversed by l-NAME, but not GW9662. l-Arginine augmented the effects of pioglitazone. In conclusion, pioglitazone alleviates symptoms in a rat model of D-IBS through an NO-dependent mechanism.

Electroacupuncture diminishes P2X2 and P2X3 purinergic receptor expression in dorsal root ganglia of rats with visceral hypersensitivity

Electroacupuncture at Shangjuxu (ST37) and Tianshu (ST25) can improve visceral hypersensitivity in rats. Colorectal distension was used to establish a rat model of chronic visceral hypersensitivity. Immunohistochemistry was used to detect P2X₂ and P2X₃ receptor expression in dorsal root ganglia from rats with chronic visceral hypersensitivity. Results demonstrated that abdominal withdrawal reflex scores obviously increased following establishment of the model, indicating visceral hypersensitivity. Simultaneously, P2X₂ and P2X₃ receptor expression increased in dorsal root ganglia. After bilateral electroacupuncture at Shangjuxu and Tianshu, abdominal withdrawal reflex scores and P2X₂ and P2X₃ receptor expression decreased in rats with visceral hypersensitivity. These results indicated that electroacupuncture treatment improved visceral hypersensitivity in rats with irritable bowel syndrome by reducing P2X₂ and P2X₃ receptor expression in dorsal root ganglia.

Acupuncture-moxibustion in treating irritable bowel syndrome: How does it work?

Irritable bowel syndrome (IBS) is a functional intestinal disease characterized by abdominal pain or discomfort and altered bowel habits. It has drawn great attention because of its high prevalence, reoccurring symptoms, and severe influence on patients’ lives. Many clinical studies have demonstrated the efficacy of acupuncture-moxibustion in treating IBS. Increasing attention has been paid to research regarding the action mechanisms of acupuncture-moxibustion for IBS, and the adoption of modern techniques has achieved some progress. This article reviews the latest advances among action mechanism studies from the perspectives of gastrointestinal motility, visceral hypersensitivity, the brain-gut axis, the neuroendocrine system, and the immune system. It is shown that acupuncture-moxibustion can effectively regulate the above items, and thus, this treatment should have a high efficacy in the treatment of IBS. This article also identifies existing problems in current mechanism research and raises several ideas for future studies. Further revelations regarding these action mechanisms will promote the application of acupuncture-moxibustion in treating IBS.

Evaluating the effectiveness of electro-acupuncture as a treatment for childhood autism using single photon emission computed tomography

OBJECTIVE

To explore the effectiveness of electro-acupuncture (EA) in the treatment of childhood autism (CA) and evaluate its effectiveness using single photon emission computed tomography (SPECT).

METHODS

A total of 55 CA patients (4.52±2.73 years) were enrolled in this study. All patients received EA treatments and were examined by SPECT before and after treatments.

RESULTS

Following treatment, the intracerebral multiple focal radioactivity distribution defect areas of CA patients were observed to be partially filled. Specifically, significant differences in the ratios of regional cerebral blood flow and global cerebral blood flow before (Fb) and after (Fe) EA treatment in different lesions were observed (in the left prefrontal cortex, t=5.01, P<0.01; in the right prefrontal cortex, t=2.32, P<0.05; in the left temporal lobe, t=4.54, P<0.01; in the right temporal lobe, t=2.90, P<0.05; in the left Broca's area, t=5.82, P<0.01). After EA treatment, the patients exhibited symptomatic relief.

CONCLUSION

EA is useful to treat CA and SPECT can be used to evaluate the effectiveness of this treatment.