Cortical-limbic regions modulate depression and anxiety factors in functional dyspepsia: a PET-CT study. Ann Nucl Med. 2012;26:35-40. [PMID: 21953211 DOI: 10.1007/s12149-011-0537-4]

Brain glucose metabolism on [18F]-FDG PET/CT: a dynamic biomarker predicting depression and anxiety in cancer patients

Objectives

To explore the correlation between the incidence rates of depression and anxiety and cerebral glucose metabolism in cancer patients.

Methods

The experiment subjects consisted of patients with lung cancer, head and neck tumor, stomach cancer, intestinal cancer, breast cancer and healthy individuals. A total of 240 tumor patients and 39 healthy individuals were included. All subjects were evaluated by the Hamilton depression scale (HAMD) and Manifest anxiety scale (MAS), and were examined by whole body Positron Emission Tomography/Computed Tomography (PET/CT) with 18F-fluorodeoxyglucose (FDG). Demographic, baseline clinical characteristics, brain glucose metabolic changes, emotional disorder scores and their relations were statistically analyzed.

Results

The incidence rates of depression and anxiety in patients with lung cancer were higher than those in patients with other tumors, and Standard uptake values (SUVs) and metabolic volume in bilateral frontal lobe, bilateral temporal lobe, bilateral caudate nucleus, bilateral hippocampus, left cingulate gyrus were lower than those in patients with other tumors. We also found that poor pathological differentiation, and advanced TNM stage independently associated with depression and anxiety risk. SUVs in the bilateral frontal lobe, bilateral temporal lobe, bilateral caudate nucleus, bilateral hippocampus, left cingulate gyrus were negatively correlated with HAMD and MAS scores.

Conclusion

This study revealed the correlation between brain glucose metabolism and emotional disorders in cancer patients. The changes in brain glucose metabolism were expected to play a major role in emotional disorders in cancer patients as psychobiological markers. These findings indicated that functional imaging can be applied for psychological assessment of cancer patients as an innovative method.

Differential responses from the left postcentral gyrus, right middle frontal gyrus, and precuneus to meal ingestion in patients with functional dyspepsia

Background

Functional dyspepsia (FD) is most often a meal-induced syndrome. Studies using resting-state functional magnetic resonance imaging (rs-fMRI) reported abnormal connectivity in areas related to pain processing in FD. However, only a few studies have attempted to determine how meal ingestion affects the brain's working patterns. Through rs-fMRI, this study observed how meal ingestion affected brain regions related to visceral hypersensitivity and emotional response networks in FD patients.

Methods

A total of 30 FD patients and 32 healthy controls (HC) were enrolled and underwent clinical investigations. Rs-fMRI was performed twice after a 4-h fast and 50 min after a meal. The mean functional connectivity strength (FCS) values were extracted from brain regions with significant differences to show the trend of changes related to meal ingestion after FCS analyses.

Results

Depression, anxiety, sleep disturbances, and weight loss were more common in FD patients (P ≤ 0.001). Compared with HCs (corrected cluster P-value < 0.05), FD patients had significantly higher FCS in the right middle frontal gyrus before meals and higher meal-induced FCS in the left postcentral gyrus. HCs had greater meal-induced activation in the right precuneus and anterior cingulate cortex. FD patients had a decreasing trend in the right inferior frontal gyrus compared to the increasing trend in HCs. We only found anxiety to be negatively correlated with FCS in the right inferior frontal gyrus in FD (r = -0.459, p = 0.048, uncorrected).

Conclusions

In this study, we discovered that FD patients have different perceptual and emotional responses to food intake in defined brain areas, providing promising impetus for understanding pathogenic brain mechanisms in FD.

Altered resting-state brain activity in functional dyspepsia patients: a coordinate-based meta-analysis

Background

Neuroimaging studies have identified aberrant activity patterns in multiple brain regions in functional dyspepsia (FD) patients. However, due to the differences in study design, these previous findings are inconsistent, and the underlying neuropathological characteristics of FD remain unclear.

Methods

Eight databases were systematically searched for literature from inception to October 2022 with the keywords "Functional dyspepsia" and "Neuroimaging." Thereafter, the anisotropic effect size signed the differential mapping (AES-SDM) approach that was applied to meta-analyze the aberrant brain activity pattern of FD patients.

Results

A total of 11 articles with 260 FD patients and 202 healthy controls (HCs) were included. The AES-SDM meta-analysis demonstrated that FD patients manifested increased activity in the bilateral insula, left anterior cingulate gyrus, bilateral thalamus, right precentral gyrus, left supplementary motor area, right putamen, and left rectus gyrus and decreased functional activity in the right cerebellum compared to the HCs. Sensitivity analysis showed that all these above regions were highly reproducible, and no significant publication bias was detected.

Conclusion

The current study demonstrated that FD patients had significantly abnormal activity patterns in several brain regions involved in visceral sensation perception, pain modulation, and emotion regulation, which provided an integrated insight into the neuropathological characteristics of FD.

Neural Responses of Acupuncture for Treating Functional Dyspepsia: An fMRI Study

Different acupoints exhibiting similar therapeutic effects are a common phenomenon in acupuncture clinical practice. However, the mechanism underlying this phenomenon remains unclear. This study aimed to investigate the similarities and differences in cerebral activities elicited through stimulation of CV12 and ST36, the two most commonly used acupoints, in the treatment of gastrointestinal diseases, so as to partly explore the mechanism of the different acupoints with similar effects. Thirty-eight eligible functional dyspepsia (FD) patients were randomly assigned into either group A (CV12 group) or group B (ST36 group). Each patient received five acupuncture treatments per week for 4 weeks. The Symptom Index of Dyspepsia (SID), Nepean Dyspepsia Symptom Index (NDSI), and Nepean Dyspepsia Life Quality Index (NDLQI) were used to assess treatment efficacy. Functional MRI (fMRI) scans were performed to detect cerebral activity changes at baseline and at the end of the treatment. The results demonstrated that (1) improvements in NDSI, SID, and NDLQI were found in both group A and group B (p < 0.05). However, there were no significant differences in the improvements of the SID, NDSI, and NDLQI scores between group A and group B (p > 0.05); (2) all FD patients showed significantly increased amplitude of low-frequency fluctuation (ALFF) in the left postcentral gyrus after acupuncture treatment, and the changes of ALFF in the left postcentral gyrus were significantly related to the improvements of SID scores (r = 0.358, p = 0.041); and (3) needling at CV12 significantly decreased the resting-state functional connectivity (rsFC) between the left postcentral gyrus and angular gyrus, caudate, middle frontal gyrus (MFG), and cerebellum, while needling at ST36 significantly increased the rsFC between the left postcentral gyrus with the precuneus, superior frontal gyrus (SFG), and MFG. The results indicated that CV12 and ST36 shared similar therapeutic effects for dyspepsia, with common modulation on the activity of the postcentral gyrus in FD patients. However, the modulatory pattern on the functional connectivity of the postcentral gyrus was different. Namely, stimulation of CV12 primarily involved the postcentral gyrus–reward network, while stimulation of ST36 primarily involved the postcentral gyrus–default mode network circuitry.

Disrupted Regional Homogeneity in Major Depressive Disorder With Gastrointestinal Symptoms at Rest

Background: Gastrointestinal (GI) symptoms are prominent in patients with major depressive disorder (MDD). Previous studies have reported brain structural and functional changes in both MDD and digestive system diseases but it remains unclear whether MDD patients with GI symptoms have brain imaging changes. Methods: We recruited 35 MDD patients with GI symptoms, 17 MDD patients without GI symptoms and 28 age-, gender-, and education-matched healthy controls. All participants were scanned by resting-state functional magnetic resonance imaging (fMRI). Imaging data were analyzed with regional homogeneity (ReHo). Results: The GI group showed higher total HRSD-17 scores, anxiety/somatization, weight loss, and sleep disturbance scores compared to the non-GI group. We found increased ReHo in the right inferior parietal gyrus (IPL), bilateral supplementary motor area (SMA), bilateral cerebellum Crus II, left inferior frontal gyrus (IFG), and bilateral superior medial frontal cortex (SMFC) and decreased ReHo in the right posterior cingulate cortex (PCC), bilateral cuneus, and left middle occipital gyrus (MOG) in patients with GI symptoms relative to the HCs. The GI group showed higher ReHo values in the bilateral precuneus than the non-GI group. Conclusion: MDD patients with GI symptoms showed a greater severity of symptoms than MDD patients without GI symptoms, particularly in terms of anxiety/somatization, weight loss, and sleep disturbances. Increased activity in the default-mode network might be associated with GI symptoms in MDD patients.

The duration of acupuncture effects and its associated factors in chronic severe functional constipation: secondary analysis of a randomized controlled trial

BACKGROUND

Electroacupuncture (EA) has been shown to improve complete spontaneous bowel movements (CSBMs), but the duration of its effects remains unknown. The objective of this study was to explore the duration of acupuncture effects after treatment and its associated factors for chronic severe functional constipation (CSFC).

METHODS

This was a secondary analysis of a multicenter, randomized, sham-acupuncture (SA) controlled trial that included 1075 participants with CSFC. The primary outcome, the duration of acupuncture effects after treatment, was the number of weeks during the 12-week follow-up period that participants were to meet the weekly CSBM responder criteria. A weekly CSBM responder was defined as a participant who had at least three CSBMs for a given week and an increase from baseline of at least one CSBM for that same week. We performed a retrospective multivariate analysis to explore potential factors associated with sustained acupuncture effects.

RESULTS

The duration of acupuncture effects in the EA group (5.5 weeks) was significantly higher than the duration of SA effects in the SA group (2.2 weeks) with a between-group difference of 3.2 weeks (95% CI, 2.77-3.78; p < 0.001). A younger age and higher baseline CSBMs per week [regression coefficient (RC) -0.06, 95% confidence interval (CI) (-0.06 to -0.04); RC 2.43, 95% CI 1.78-3.60; respectively] were associated with longer durations of acupuncture effects.

CONCLUSIONS

EA had sustained post-treatment effects for CFSC. A significant association among a younger age, higher baseline CSBMs and sustained acupuncture effects was observed. Further research is needed to confirm the association.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT01726504). Registered on 26 August 2012.

Assigning Clinical Significance and Symptom Severity Using the Zung Scales: Levels of Misclassification Arising from Confusion between Index and Raw Scores

BACKGROUND

The Zung Self-Rating Depression Scale (SDS) and Self-Rating Anxiety Scale (SAS) are two norm-referenced scales commonly used to identify the presence of depression and anxiety in clinical research. Unfortunately, several researchers have mistakenly applied index score criteria to raw scores when assigning clinical significance and symptom severity ratings. This study examined the extent of this problem.

METHOD

102 papers published over the six-year period from 2010 to 2015 were used to establish two convenience samples of 60 usages of each Zung scale.

RESULTS

In those papers where cut-off scores were used (i.e., 45/60 for SDS and 40/60 for SAS), up to 51% of SDS and 45% of SAS papers involved the incorrect application of index score criteria to raw scores. Inconsistencies were also noted in the severity ranges and cut-off scores used.

CONCLUSIONS

A large percentage of publications involving the Zung SDS and SAS scales are using incorrect criteria for the classification of clinically significant symptoms of depression and anxiety. The most common error-applying index score criteria to raw scores-produces a substantial elevation of the cut-off points for significance. Given the continuing usage of these scales, it is important that these inconsistencies be highlighted and resolved.

Acute engagement of Gq-mediated signaling in the bed nucleus of the stria terminalis induces anxiety-like behavior

The bed nucleus of the stria terminalis (BNST) is a brain region important for regulating anxiety-related behavior in both humans and rodents. Here we used a chemogenetic strategy to investigate how engagement of G protein-coupled receptor (GPCR) signaling cascades in genetically defined GABAergic BNST neurons modulates anxiety-related behavior and downstream circuit function. We saw that stimulation of vesicular γ-aminobutyric acid (GABA) transporter (VGAT)-expressing BNST neurons using hM3Dq, but neither hM4Di nor rM3Ds designer receptors exclusively activated by a designer drug (DREADD), promotes anxiety-like behavior. Further, we identified that activation of hM3Dq receptors in BNST VGAT neurons can induce a long-term depression-like state of glutamatergic synaptic transmission, indicating DREADD-induced changes in synaptic plasticity. Further, we used DREADD-assisted metabolic mapping to profile brain-wide network activity following activation of Gq-mediated signaling in BNST VGAT neurons and saw increased activity within ventral midbrain structures, including the ventral tegmental area and hindbrain structures such as the locus coeruleus and parabrachial nucleus. These results highlight that Gq-mediated signaling in BNST VGAT neurons can drive downstream network activity that correlates with anxiety-like behavior and points to the importance of identifying endogenous GPCRs within genetically defined cell populations. We next used a microfluidics approach to profile the receptorome of single BNST VGAT neurons. This approach yielded multiple Gq-coupled receptors that are associated with anxiety-like behavior and several potential novel candidates for regulation of anxiety-like behavior. From this, we identified that stimulation of the Gq-coupled receptor 5-HT2CR in the BNST is sufficient to elevate anxiety-like behavior in an acoustic startle task. Together, these results provide a novel profile of receptors within genetically defined BNST VGAT neurons that may serve as therapeutic targets for regulating anxiety states and provide a blueprint for examining how G-protein-mediated signaling in a genetically defined cell type can be used to assess behavior and brain-wide circuit function.

Changes of the brain activities after chronic restraint stress in rats: A study based on 18F-FDG PET

As a prevalent disease all over the world, changed functional activities and/or structures in many brain regions have been found in depression. In this study, 5-week chronic restraint stress (CRS) was performed to establish depression rat models, and ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) was used to detect brain functional activities. Our study found that CRS induced depressive behaviors and increased the expression of serum IL-6. After exposure to CRS, rats showed decreased glucose metabolism in the whole-brain and brain regions including left medial prefrontal and auditory cortices; right amygdala, cingulate cortex, olfactory and AcbCore/Shell; bilateral caudate putamen, dorsal hippocampi, insular and entorhinal cortices. Expression of serum IL-6 and glucose metabolism in most of the above brain regions were significantly correlated with the severity of some CRS-induced depressive behaviors. In conclusion, the increased peripheral inflammatory response and decreased brain functional activities might be the important pathogenesis of experimental depression induced by CRS, and could reflect the severity of depression to some extent.

Functional neuroimaging studies in functional dyspepsia patients: a systematic review

BACKGROUND

There is increasing evidence in support of the presence of abnormal central changes (compared to healthy controls) in functional dyspepsia (FD) in addition to the peripheral changes in gastrointestinal tract.

PURPOSE

This systematic review aims to provide an integrative understanding of the abnormal functional brain activity, visceral sensation, dyspeptic symptoms, and psychological changes of FD. Electronic and hand searches were conducted to identify functional neuroimaging studies involving FD patients. Sixteen studies were selected and divided into three categories: 10 resting state studies, three visceral distention studies, and three acupuncture studies. Changes were reported in several brain areas in FD patients including the frontal cortex, somatosensory cortex, insula, anterior cingulate cortex, thalamus, hippocampus, and amygdala. These brain activity changes were associated with visceral hypersensitivity, dyspeptic symptoms, poorer quality of life, anxiety, and depression. The results show that FD is associated with functional abnormalities in sensory and pain modulation, emotion, saliency, and homeostatic processing regions. The diversity of conditions, heterogeneous results, poorly standardized diagnoses of FD, and various comorbidities may be responsible for the variability in the results.

Biopsychosocial Aspects of Functional Gastrointestinal Disorders

In this paper, we provide a general framework for understanding the functional gastrointestinal disorders (FGID) from a biopsychosocial perspective. More specifically, we provide an overview of the recent research on how the complex interactions of environmental, psychological, and biological factors contribute to the development and maintenance of the FGID. We emphasize that considering and addressing all these factors is a conditio sine qua non for appropriate treatment of these conditions. First, we provide an overview of what is currently known about how each of these factors - the environment, including the influence of those in an individual's family, the individual's own psychological states and traits, and the individual's (neuro)physiological make-up - interact to ultimately result in the generation of FGID symptoms. Second, we provide an overview of commonly used assessment tools which can assist clinicians in obtaining a more comprehensive assessment of these factors in their patients. Finally, the broader perspective outlined earlier is applied to provide an overview of centrally acting treatment strategies, both psychological and pharmacological, which have been shown to be efficacious to treat FGID.

Cerebral responses to puncturing at different acupoints for treating meal-related functional dyspepsia

BACKGROUND

To investigate the similarities and differences in cerebral responses to puncturing at different acupoints for treating meal-related functional dyspepsia (FD).

METHODS

Twenty right-handed FD patients were enrolled and randomized divided into two groups. Each patient received 20 sessions' electro-acupuncture treatment. The acupoints used in Group A were four acupoints on the Stomach Meridian, and the acupoints used in Group B were four acupoints on the Gallbladder Meridian. PET-CT scans were performed before and after acupuncture treatment to record the changes of cerebral glycometabolism.

KEY RESULTS

After treatment, the dyspepsia symptoms and the quality of life (QOL) of the patients in each group were significantly improved (p < 0.05) and there was insignificant difference in efficacy between the two groups (p > 0.05). In Group A, deactivation in brainstem, bilateral anterior cingulate cortex (ACC) and cerebellum, left superior medial frontal gyrus, orbital frontal cortex (OFC), and thalamus, etc., and activation in bilateral middle cingulate cortex (MCC), precuneus and lingual gyrus, etc. were observed. In Group B, deactivation in brainstem, bilateral thalamus, putamen, ACC, postterior cingulate cortex, hippocampus and cerebellum, etc., and activation in bilateral MCC, precuneus, left OFC, etc. were observed (p < 0.05, Family-wise error corrected).

CONCLUSIONS & INFERENCES

Different acupoints have similar clinical efficacy but relatively different cerebral responses. The influence on the sensory transduction regions (brainstem and thalamus) and visceral modulation regions might be the common mechanism of different acupoints treating for FD, and the modulation on some emotion/cognition-related areas (e.g., prefrontal cortex) is the potential difference between the different acupoints.

Mite improves gastric emptying in patients with functional dyspepsia

AIM: To explore the effect of Mite on gastric emptying in patients with functional dyspepsia (FD).

METHODS: One hundred and two patients with FD were randomly divided into either an experimental group or a control group. The control group was treated with mosapride citrate tablets, while the experimental group was treated with Mite on the basis of mosapride citrate tablets. The clinical effects and index of gastric emptying were compared between the two groups.

RESULTS: The significant improvement rate and the total response rate were significantly higher in the experimental group than in the control group (58.82% vs 39.22%, 94.12% vs 70.59, P < 0.05). The rates of gastric emptying and the total rate of gastric emptying at 2 and 5 h in the experimental group were significantly higher than those in the control group (23.53% vs 11.76%, 94.12% vs 52.94%, 55.00% vs 30.00%, 95.00% vs 65.00%, P < 0.05).

CONCLUSION: Treatment with Mite can improve gastric emptying in FD patients.

The role of psychosocial factors and psychiatric disorders in functional dyspepsia

In this Review, after a brief historical introduction, we first provide an overview of epidemiological studies that demonstrate an association between functional dyspepsia and psychological traits, states or psychiatric disorders. These studies suggest an important intrinsic role for psychosocial factors and psychiatric disorders, especially anxiety and depression, in the aetiopathogenesis of functional dyspepsia, in addition to their putative influence on health-care-seeking behaviour. Second, we describe pathophysiological evidence on how psychosocial factors and psychiatric disorders might exert their role in functional dyspepsia. Novel insights from functional brain imaging studies regarding the integration of gut-brain signals, processed in homeostatic-interoceptive brain regions, with input from the exteroceptive system, the reward system and affective and cognitive circuits, help to clarify the important role of psychological processes and psychiatric morbidity. We therefore propose an integrated model of functional dyspepsia as a disorder of gut-brain signalling, supporting a biopsychosocial approach to the diagnosis and management of this disorder.

Advances in understanding the relationship between functional dyspepsia and mental factors

The co-morbidity of functional dyspepsia (FD) and mental disorders is 42%-61%. Growing evidence shows that visceral hypersensitivity and abnormality of brain gut peptides are possibly responsible for the interactions between FD and mental disorders, and the brain-intestine axis plays a crucial role in the development of visceral pain. Functional magnetic resonance imaging is a novel and effective tool for studying visceral hypersensitivity. Gastric pain activates a wide range of cortical and subcortical structures, including the cortex of frontal lobe, anterior cingulate cortices, insula, thalamus and amygdala. Several studies show that selected serotonergic antidepressants and some traditional Chinese medicine can improve the symptoms, especially pain, of FD; however, the underlying mechanisms remain unclear.