Tag: limbic system

Exploring the central mechanism of mind-regulation electroacupuncture in treatment of chronic fatigue syndrome with anxiety and depression comorbidity based on functional magnetic resonance imaging

Abstract:

in English, Chinese

Objectives: To observe the changes in the regional homogeneity (ReHo) and functional brain network in treatment of chronic fatigue syndrome (CFS) with anxiety and depression comorbidity with the mind-regulation electroacupuncture (EA), using resting-state functional magnetic resonance imaging (rs-fMRI).

Methods: Thirty CFS patients with anxiety and depression comorbidity were enrolled from medical staffs as the observation group. The other 30 healthy subjects were recruited from medical university students as the control group, matching gender, age and education years with the observation group. No any acupuncture intervention was delivered in the control group, and EA for regulating the mind was operated in the observation group. Main points were the emotional area of Sun‘s scalp acupuncture, the regions 1 and 8 of Sun‘s abdominal acupuncture. Supplementary acupoints included Baihui (GV 20), Guanyuan (CV 4) and bilateral.

Results: The scores of the five domains in MFI-20 (i.e. general fatigue, physical fatigue, mental fatigue, reduced motivation and reduced activity), the total score of MFI-20, and the scores of SDS, SAS and PSQI in the observation group before treatment were higher than those of the control group (P<0.05). Except the score of reduced motivation in MFI-20, the scores of the other domains and the total score of MFI-20, as well as the scores of SDS, SAS and PSQI after treatment were lower than those before treatment in the observation group (P<0.05).

Compared with the values before treatment, ReHo value was increased in the the right precuneus and decreased in the left inferior temporal gyrus and the left angular gyrus of the brain in the observation group after treatment. In the observation group, when compared with the control group, ReHo values were increased in the left inferior cerebral lobe, the interhemispheric region, the right occipital lobe and the thalamus; and it was reduced in the left middle temporal gyrus, the right posterior central gyrus, the right middle temporal gyrus, the right orbital middle frontal gyrus, the paracentral lobule and the right fusiform gyrus before treatment.

In the observation group, the functional connectivity was decreased between the right thalamus and the left posterior central gyrus, the right hippocampus and the right fusiform gyrus before treatment, respectively; it was re-constructed after treatment between the right thalamus and the left posterior central gyrus, and the right fusiform gyrus.

Compared with the control group, the functional connectivity between the right thalamus and the left posterior central gyrus, the right hippocampus, and the right fusiform gyrus was reduced before treatment; while after treatment, the functional connectivity was reduced between the right thalamus and the hippocampus in the observation group. With Spearman correlation analysis between the differential brain regions and the scores of MFI-20, SAS, SDS and PSQI, it was found that the left middle temporal gyrus, the paracentral lobule, the right precuneus, and the left inferior temporal gyrus had a partial positive correlation with the above clinical scales; and the interhemispheric region, the thalamus, the right fusiform gyrus, and the right middle temporal gyrus showed a partial negative correlation.

Conclusions: There is the decrease of ReHo in many brain regions and the numbers of the local brain functional network connectivity in CFS patients with anxiety and depression comorbidity. The mind-regulation electroacupuncture therapy may relieve the clinical symptoms of the patients through adjusting the abnormal brain regions and activating emotion-related brain regions.

Source: Zeng X, Feng C, Zhang M, Cheng W, Sun Z, Yang T. Exploring the central mechanism of mind-regulation electroacupuncture in treatment of chronic fatigue syndrome with anxiety and depression comorbidity based on functional magnetic resonance imaging. Zhongguo Zhen Jiu. 2023 Jan 12;44(1):3-11. English, Chinese. doi: 10.13703/j.0255-2930.20230603-k0003. PMID: 38191152. https://pubmed.ncbi.nlm.nih.gov/38191152/

Post-COVID cognitive deficits at one year are global and associated with elevated brain injury markers and grey matter volume reduction: national prospective study

Abstract:

The spectrum, pathophysiology, and recovery trajectory of persistent post-COVID-19 cognitive deficits are unknown, limiting our ability to develop prevention and treatment strategies. We report the one-year cognitive, serum biomarker, and neuroimaging findings from a prospective, national longitudinal study of cognition in 351 COVID-19 patients who had required hospitalisation, compared to 2,927 normative matched controls.

Cognitive deficits were global and associated with elevated brain injury markers and reduced anterior cingulate cortex volume one year after admission. The severity of the initial infective insult, post-acute psychiatric symptoms, and a history of encephalopathy were associated with greatest deficits. There was strong concordance between subjective and objective cognitive deficits. Treatment with corticosteroids during the acute phase appeared protective against cognitive deficits. Together, these findings support the hypothesis that brain injury in moderate to severe COVID-19 is immune-mediated, and should guide the development of therapeutic strategies.

Source: Benedict Michael, Greta Wood, Brendan Sargent et al. Post-COVID cognitive deficits at one year are global and associated with elevated brain injury markers and grey matter volume reduction: national prospective study, 05 January 2024, PREPRINT (Version 1) available at Research Square [https://doi.org/10.21203/rs.3.rs-3818580/v1] https://www.researchsquare.com/article/rs-3818580/v1 (Full text)

Brain-regional characteristics and neuroinflammation in ME/CFS patients from neuroimaging: A systematic review and meta-analysis

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating condition characterized by an elusive etiology and pathophysiology. This study aims to evaluate the pathological role of neuroinflammation in ME/CFS by conducting an exhaustive analysis of 65 observational studies.

Four neuroimaging techniques, including magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), electroencephalography (EEG), and positron emission tomography (PET), were employed to comparatively assess brain regional structure, metabolite profiles, electrical activity, and glial activity in 1529 ME/CFS patients (277 males, 1252 females) and 1715 controls (469 males, 1246 females). Clinical characteristics, including sex, age, and fatigue severity, were consistent with established epidemiological patterns.

Regional alterations were most frequently identified in the cerebral cortex, with a notable focus on the frontal cortex. However, our meta-analysis data revealed a significant hypoactivity in the insular and thalamic regions, contrary to observed frequencies. These abnormalities, occurring in pivotal network hubs bridging reason and emotion, disrupt connections with the limbic system, contributing to the hallmark symptoms of ME/CFS.

Furthermore, we discuss the regions where neuroinflammatory features are frequently observed and address critical neuroimaging limitations, including issues related to inter-rater reliability. This systematic review serves as a valuable guide for defining regions of interest (ROI) in future neuroimaging investigations of ME/CFS

Source: Lee JS, Sato W, Son CG. Brain-regional characteristics and neuroinflammation in ME/CFS patients from neuroimaging: A systematic review and meta-analysis. Autoimmun Rev. 2023 Nov 26:103484. doi: 10.1016/j.autrev.2023.103484. Epub ahead of print. PMID: 38016575. https://www.sciencedirect.com/science/article/pii/S1568997223002185 (Full text)

Alteration of Cortical Volume and Thickness in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Myalgic Encephalomyelitis/Chronic fatigue syndrome (ME/CFS) patients suffer from neurocognitive impairment. In this study, we investigated cortical volumetric and thickness changes in ME/CFS patients and healthy controls (HC). We estimated mean surface-based cortical volume and thickness from 18 ME/CFS patients who met International Consensus Criteria (ICC) and 26 HC using FreeSurfer. Vertex-wise analysis showed significant reductions in the caudal middle frontal gyrus (p = 0.0016) and precuneus (p = 0.013) thickness in ME/CFS patients compared with HC.

Region based analysis of sub-cortical volumes found that amygdala volume (p = 0.002) was significantly higher in ME/CFS patients compared with HC. We also performed interaction-with-group regressions with clinical measures to test for cortical volume and thickness correlations in ME/CFS with opposite slopes to HC (abnormal). ME/CFS cortical volume and thickness regressions with fatigue, heart-rate variability, heart rate, sleep disturbance score, respiratory rate, and cognitive performance were abnormal. Our study demonstrated different cortical volume and thickness in ME/CFS patients and showed abnormal cortical volume and thickness regressions with key symptoms of ME/CFS patients.

Source: Thapaliya Kiran, Marshall-Gradisnik Sonya, Staines Donald, Su Jiasheng, Barnden Leighton. Alteration of Cortical Volume and Thickness in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Frontiers in Neuroscience, Vol 16, 2022. DOI=10.3389/fnins.2022.848730 https://www.frontiersin.org/articles/10.3389/fnins.2022.848730/full   (Full text)

Risk factors and multidimensional assessment of long COVID fatigue: a nested case-control study

Abstract:

Background: Fatigue is the most prevalent and debilitating long COVID symptom, however risk factors and pathophysiology of this condition remain unknown. We assessed risk factors for long COVID fatigue and explored its possible pathophysiology.

Methods: Nested case-control study in a COVID recovery clinic. Individuals with (cases) and without (controls) significant fatigue were included. We performed a multidimensional assessment evaluating various parameters, including pulmonary function tests and cardiopulmonary exercise testing, and implemented multivariable logistic regression to assess risk factors for significant long COVID fatigue.

Results: Total of 141 individuals were included. Mean age was 47 (SD 13) years; 115 (82%) were recovering from mild COVID-19. Mean time for evaluation was 8 months following COVID-19. Sixty-six (47%) individuals were classified with significant long COVID fatigue. They had significantly higher number of children, lower proportion of hypothyroidism, higher proportion of sore throat during acute illness and long COVID symptoms, and of physical limitation in daily activities. Individuals with fatigue had poorer sleep quality and higher degree of depression. They had significantly lower heart rate [153.52 (22.64) vs 163.52 (18.53), p=0.038] and oxygen consumption per Kg [27.69 (7.52) vs 30.71 (7.52), p=0.036] at peak exercise. The two independent risk factors for fatigue identified in multivariable analysis were peak exercise heart rate (odds ratio [OR] 0.79 per 10 beats/minute, 95% confidence interval [CI] 0.65-0.96, p=0.019); and long COVID memory impairment (OR 3.76, 95% CI 1.57-9.01, p=0.003).

Conclusions: Long COVID fatigue may be related to autonomic dysfunction, impaired cognition and decreased mood. This may suggest a limbic-vagal pathophysiology. Clinical Trial registration: NCT04851561.

Source: Margalit I, Yelin D, Sagi M, Rahat MM, Sheena L, Mizrahi N, Gordin Y, Agmon H, Epstein NK, Atamna A, Tishler O, Daitch V, Babich T, Abecasis D, Yarom Y, Kazum S, Shitenberg D, Baltaxe E, Elkana O, Shapira-Lichter I, Leibovici L, Yahav D. Risk factors and multidimensional assessment of long COVID fatigue: a nested case-control study. Clin Infect Dis. 2022 Apr 11:ciac283. doi: 10.1093/cid/ciac283. Epub ahead of print. PMID: 35403679.  https://pubmed.ncbi.nlm.nih.gov/35403679/

Volumetric differences in hippocampal subfields and associations with clinical measures in myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) patients suffer from a cognitive and memory dysfunction. Because the hippocampus plays a key role in both cognition and memory, we tested for volumetric differences in the subfields of the hippocampus in ME/CFS.

We estimated hippocampal subfield volumes for 25 ME/CFS patients who met Fukuda criteria only (ME/CFSFukuda ), 18 ME/CFS patients who met the stricter ICC criteria (ME/CFSICC ), and 25 healthy controls (HC). Group comparisons with HC detected extensive differences in subfield volumes in ME/CFSICC but not in ME/CFSFukuda . ME/CFSICC patients had significantly larger volume in the left subiculum head (p < 0.001), left presubiculum head (p = 0.0020), and left fimbria (p = 0.004).

Correlations of hippocampus subfield volumes with clinical measures were stronger in ME/CFSICC than in ME/CFSFukuda patients. In ME/CFSFukuda patients, we detected positive correlations between fatigue and hippocampus subfield volumes and a negative correlation between sleep disturbance score and the right CA1 body volume.

In ME/CFSICC patients, we detected a strong negative relationship between fatigue and left hippocampus tail volume. Strong negative relationships were also detected between pain and SF36 physical scores and two hippocampal subfield volumes (left: GC-ML-DG head and CA4 head).

Our study demonstrated that volumetric differences in hippocampal subfields have strong statistical inference for patients meeting the ME/CFSICC case definition and confirms hippocampal involvement in the cognitive and memory problems of ME/CFSICC patients.

Source: Thapaliya K, Staines D, Marshall-Gradisnik S, Su J, Barnden L. Volumetric differences in hippocampal subfields and associations with clinical measures in myalgic encephalomyelitis/chronic fatigue syndrome. J Neurosci Res. 2022 Mar 31. doi: 10.1002/jnr.25048. Epub ahead of print. PMID: 35355311. https://onlinelibrary.wiley.com/doi/10.1002/jnr.25048  (Full study)

Limbic Perfusion Is Reduced in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is an illness characterized by a diverse range of debilitating symptoms including autonomic, immunologic, and cognitive dysfunction. Although neurological and cognitive aberrations have been consistently reported, relatively little is known regarding the regional cerebral blood flow (rCBF) in ME/CFS.

In this study, we studied a cohort of 31 ME/CSF patients (average age: 42.8 ± 13.5 years) and 48 healthy controls (average age: 42.9 ± 12.0 years) using the pseudo-continuous arterial spin labeling (PCASL) technique on a whole-body clinical 3T MRI scanner. Besides routine clinical MRI, the protocol included a session of over 8 min-long rCBF measurement. The differences in the rCBF between the ME/CSF patients and healthy controls were statistically assessed with voxel-wise and AAL ROI-based two-sample t-tests. Linear regression analysis was also performed on the rCBF data by using the symptom severity score as the main regressor.

In comparison with the healthy controls, the patient group showed significant hypoperfusion (uncorrected voxel wise p ≤ 0.001, FWE p ≤ 0.01) in several brain regions of the limbic system, including the anterior cingulate cortex, putamen, pallidum, and anterior ventral insular area. For the ME/CFS patients, the overall symptom severity score at rest was significantly associated with a reduced rCBF in the anterior cingulate cortex. The results of this study show that brain blood flow abnormalities in the limbic system may contribute to ME/CFS pathogenesis.

Source: Li X, Julin P, Li TQ. Limbic Perfusion Is Reduced in Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Tomography. 2021 Nov 1;7(4):675-687. doi: 10.3390/tomography7040056. PMID: 34842817.  https://www.mdpi.com/2379-139X/7/4/56 (Full text)

A Paradigm for Post-Covid-19 Fatigue Syndrome Analogous to ME/CFS

Abstract:

A significant proportion of COVID-19 patients are suffering from prolonged Post-COVID-19 Fatigue Syndrome, with characteristics typically found in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). However, no clear pathophysiological explanation, as yet, has been provided. A novel paradigm for a Post-COVID-19 Fatigue Syndrome is developed here from a recent unifying model for ME/CFS. Central to its rationale, SARS-CoV-2, in common with the triggers (viral and non-viral) of ME/CFS, is proposed to be a physiologically severe stressor, which could be targeting a stress-integrator, within the brain: the hypothalamic paraventricular nucleus (PVN). It is proposed that inflammatory mediators, released at the site of COVID-19 infection, would be transmitted as stress-signals, via humoral and neural pathways, which overwhelm this stress-center.

In genetically susceptible people, an intrinsic stress-threshold is suggested to be exceeded causing ongoing dysfunction to the hypothalamic PVN’s complex neurological circuitry. In this compromised state, the hypothalamic PVN might then be hyper-sensitive to a wide range of life’s ongoing physiological stressors. This could result in the reported post-exertional malaise episodes and more severe relapses, in common with ME/CFS, that perpetuate an ongoing disease state.

When a certain stress-tolerance-level is exceeded, the hypothalamic PVN can become an epicenter for microglia-induced activation and neuroinflammation, affecting the hypothalamus and its proximal limbic system, which would account for the range of reported ME/CFS-like symptoms. A model for Post-COVID-19 Fatigue Syndrome is provided to stimulate discussion and critical evaluation. Brain-scanning studies, incorporating increasingly sophisticated imaging technology should enable chronic neuroinflammation to be detected, even at a low level, in the finite detail required, thus helping to test this model, while advancing our understanding of Post-COVID-19 Fatigue Syndrome pathophysiology.

Source: Mackay A. A Paradigm for Post-Covid-19 Fatigue Syndrome Analogous to ME/CFS. Front Neurol. 2021 Aug 2;12:701419. doi: 10.3389/fneur.2021.701419. PMID: 34408721; PMCID: PMC8365156. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8365156/ (Full text)

Do anorexia, irritable bowel syndrome, chronic fatigues share a common cause?

Irritable bowel syndrome, chronic fatigue syndrome and anorexia nervosa may all have a common origin according to researchers.

They speculate that all three disorders may be caused by antibodies to the body’s own nerve cells because of a mistake by the immune system following infection.

At the moment, the ultimate cause of these illnesses remains a mystery.

Writing in Medical Hypotheses, Dr Jim Morris from the University Hospitals of Morecambe Bay NHS Trust, Dr Sue Broughton and Dr Quenton Wessels from Lancaster University say current explanations are unsatisfactory.

“Psychological factors might be important, but are unconvincing as the primary or major cause.

“There might, for instance, be an increased incidence of physical and sexual abuse in childhood in those who go on to manifest functional disorders. It is easy to see how this could influence symptoms in adults but it stretches credulity to imagine abuse as the sole and sufficient cause of the functional disorder.”

It is already well known that women are more at increased risk of autoimmune disease especially ones in which antibodies to the body’s own cells are thought to play a role, like thyroid disease, pernicious anemia and myasthenia gravis.

The researchers said: “The female to male ratio in these conditions is of the order of 10. The female excess in Irritable Bowel Syndrome, Chronic Fatigue Syndrome and Anorexia Nervosa is equally extreme and therefore this fits with the idea that auto-antibodies to nerve cells could be part of the pathogenesis of these conditions.”

The formation of auto-antibodies is found mostly among women and increases with age, which could be why these disorders are more common in midlife. Even with anorexia, which reaches a peak at the age of 30, auto-antibodies have been found in the bodies of patients.

There are also links with infection in that the onset of IBS commonly follows an episode of infectious diarrhea while chronic fatigue syndrome can be triggered by infectious mononucleosis and viral hepatitis.

Even anorexia could be influenced by secretions from bacteria affecting the brain, triggering the production of antibodies which affect mood and motivation.

“Auto-antibodies acting on the (brain’s) limbic system could induce extremes of emotion including disgust and fear. These then become linked, in the minds of adolescent girls, to culturally determined ideas of what is, and what is not, the ideal body shape and size. It is then a small step for disgust and fear to be directed to food and obesity which the fashion industry currently demonizes.”

If their idea is proven, the researchers suggest that these disorders may be amenable to treatment using pooled immunoglobulin from the blood of healthy people, especially in severe cases of anorexia where life is threatened. It should also be possible to identify and eliminate from the gut the bacteria which are triggering auto-antibodies.

Journal Reference: J.A. Morris, S.J. Broughton, Q. Wessels. Microbes, molecular mimicry and molecules of mood and motivation. Medical Hypotheses, 2016; 87: 40 DOI:10.1016/j.mehy.2015.12.011

 

Source: Lancaster University. “Do anorexia, irritable bowel syndrome, chronic fatigues share a common cause?.” ScienceDaily. ScienceDaily, 25 April 2016. https://www.sciencedaily.com/releases/2016/04/160425100204.htm

 

Autonomic correlations with MRI are abnormal in the brainstem vasomotor centre in Chronic Fatigue Syndrome

Abstract:

Autonomic changes are often associated with the chronic fatigue syndrome (CFS), but their pathogenetic role is unclear and brain imaging investigations are lacking. The vasomotor centre and, through it, nuclei in the midbrain and hypothalamus play a key role in autonomic nervous system regulation of steady state blood pressure (BP) and heart rate (HR).

In this exploratory cross-sectional study, BP and HR, as indicators of autonomic function, were correlated with volumetric and T1- and T2-weighted spin-echo (T1w and T2w) brain MRI in 25 CFS subjects and 25 normal controls (NC). Steady state BP (systolic, diastolic and pulse pressure) and HR in two postures were extracted from 24 h blood pressure monitoring. We performed (1) MRI versus autonomic score interaction-with-group regressions to detect locations where regression slopes differed in the CFS and NC groups (collectively indicating abnormality in CFS), and (2) MRI regressions in the CFS and NC groups alone to detect additional locations with abnormal correlations in CFS.

Significant CFS regressions were repeated controlling for anxiety and depression (A&D). Abnormal regressions were detected in nuclei of the brainstem vasomotor centre, midbrain reticular formation and hypothalamus, but also in limbic nuclei involved in stress responses and in prefrontal white matter. Group comparisons of CFS and NC did not find MRI differences in these locations.

We propose therefore that these regulatory nuclei are functioning correctly, but that two-way communication between them is impaired in CFS and this affects signalling to/from peripheral effectors/sensors, culminating in inverted or magnified correlations. This single explanation for the diverse abnormal correlations detected here consolidates the conclusion for a brainstem/midbrain nerve conduction deficit inferred earlier (Barnden et al., 2015). Strong correlations were also detected in isolated NC regressions.

 

Source: Barnden LR, Kwiatek R, Crouch B, Burnet R, Del Fante P. Autonomic correlations with MRI are abnormal in the brainstem vasomotor centre in Chronic Fatigue Syndrome. Neuroimage Clin. 2016 Mar 31;11:530-7. doi: 10.1016/j.nicl.2016.03.017. ECollection 2016. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4833047/ (Full article)