[Mind-regulating and spleen-strengthening needling technique improves abdominal hypersensitivity and emotion by enhancing functional connectivity between hippocampus and brain regions in diarrhea-predominant irritable bowel syndrome patients].

OBJECTIVE

To compare the difference of brain functional connectivity between diarrhea-predominant irritable bowel syndrome (IBS-D) patients and healthy volunteers and changes after acupuncture intervention, so as to investigate the underlying mechanism of acupuncture in regulating functional activities of IBS-D patients by using seed point correlation analysis.

METHODS

A total of 25 IBS-D patients and 25 healthy volunteers were recruited in the present study and respectively attributed to acupuncture group and control group. The IBS-D patients received manual acupuncture stimulation of Baihui (GV20), Yintang (EX-HN3), and bilateral Tianshu (ST25), Zusanli (ST36), Shangjuxu (ST37), Sanyinjiao (SP6) and Taichong (LR3) with mind-regulating and spleen-strengthening technique for 30 min, once a day, 3 days a week for 6 weeks. Before and after the intervention, the IBS symptom severity scale (IBS-SSS) was used to assess the patients' state of abdominal pain, distention and defecation, and Hamilton Anxiety Rating Scale (HAMA) employed to evaluate the patients' anxiety severity. The resting state functional magnetic resonance imaging (rs-fMRI) data were acquired and preprocessed by using SPM8 and DPARSE soft-wares. Seeds (bilate-ral hippocampus regions) to whole-brain analysis was performed to obtain the mean time series of the left and right seed regions, followed by making Pearson correlation analysis to obtain the correlation coefficient (time series from each seed region with the rest of the voxels in the brain), and making a multivariate comparative correction to get data of functional connectivity (FC) of bilateral hippocampus regions and to find the related difference in the brain regions. Then, the differences of the FC of brain regions between IBS-D patients and healthy volunteers were compared.

RESULTS

Following acupuncture treatment, both the HAMA and IBS-SSS scores were significantly reduced in the acupuncture group compared with its pre-treatment (<0.01). Compared with the healthy volunteers, there were a reduction in the functional connectivity between the left hippocampus seed region and the right inferior temporal gyrus, left fusiform gyrus and left superior gyrus, and between the right hippocampus region and the right fusiform gyrus, left inferior temporal gyrus, left inferior occipital gyrus, left rectus gyrus, left insula, left precuneus, right angular gyrus, left middle occipital gyrus, right precuneus, and the left superior temporal gyrus, and an increase in the FC between the left hippocampus and left superior temporal gyrus was increased in ISB-D patients. Self-comparison showed that after the treatment, the FC was increased between the left hippocampus seed region and the right inferior temporal gyrus, left fusiform gyrus, bilateral lingual gyrus, left amygdala, right inferior occipital gyrus, right insula, right middle frontal gyrus, left middle frontal gyrus and the left middle occipital gyrus; and between the right hippocampus seed region and the posterior inferior cerebellar lobe, left inferior temporal gyrus, left suboccipital gyrus, right fusiform gyrus, left insula, right inferior frontal gyrus, left superior temporal gyrus, left middle occipital gyrus, right middle frontal gyrus, left supplementary motor area and right supplementary motor area, and decreased between the left hippocampus region and the left anterior cingulate, paracingulate gyrus and the right posterior central gyrus in IBS-D patients.

CONCLUSION

Mind-regulating and spleen-strengthening acupuncture intervention may improve the abdominal pain and distension and emotional state in IBS-D patients, which is possibly associated with its effect in enhancing FC between the hippocampus and brain regions.