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Feng Y, Huang Z, Ma X, Zong X, Xu P, Lin HW, Zhang Q. Intermittent theta-burst stimulation alleviates hypoxia-ischemia-caused myelin damage and neurologic disability. Exp Neurol 2024; 378:114821. [PMID: 38782349 PMCID: PMC11214828 DOI: 10.1016/j.expneurol.2024.114821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 05/01/2024] [Accepted: 05/19/2024] [Indexed: 05/25/2024]
Abstract
Neonatal hypoxia-ischemia (HI) results in behavioral deficits, characterized by neuronal injury and retarded myelin formation. To date, limited treatment methods are available to prevent or alleviate neurologic sequelae of HI. Intermittent theta-burst stimulation (iTBS), a non-invasive therapeutic procedure, is considered a promising therapeutic tool for treating some neurocognitive disorders and neuropsychiatric diseases. Hence, this study aims to investigate whether iTBS can prevent the negative behavioral manifestations of HI and explore the mechanisms for associations. We exposed postnatal day 10 Sprague-Dawley male and female rats to 2 h of hypoxia (6% O2) following right common carotid artery ligation, resulting in oligodendrocyte (OL) dysfunction, including reduced proliferation and differentiation of oligodendrocyte precursor cells (OPCs), decreased OL survival, and compromised myelin in the corpus callosum (CC) and hippocampal dentate gyrus (DG). These alterations were concomitant with cognitive dysfunction and depression-like behaviors. Crucially, early iTBS treatment (15 G, 190 s, seven days, initiated one day post-HI) significantly alleviated HI-caused myelin damage and mitigated the neurologic sequelae both in male and female rats. However, the late iTBS treatment (initiated 18 days after HI insult) could not significantly impact these behavioral deficits. In summary, our findings support that early iTBS treatment may be a promising strategy to improve HI-induced neurologic disability. The underlying mechanisms of iTBS treatment are associated with promoting the differentiation of OPCs and alleviating myelin damage.
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Affiliation(s)
- Yu Feng
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, 1501 Kings Highway, LA 71103, USA
| | - Zhihai Huang
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, 1501 Kings Highway, LA 71103, USA
| | - Xiaohui Ma
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, 1501 Kings Highway, LA 71103, USA
| | - Xuemei Zong
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, 1501 Kings Highway, LA 71103, USA
| | - Peisheng Xu
- Department of Drug Discovery and Biomedical Sciences, University of South Carolina, College of Pharmacy, 715 Sumter Street, CLS609D, Columbia, SC 29208, USA
| | - Hung Wen Lin
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, 1501 Kings Highway, LA 71103, USA
| | - Quanguang Zhang
- Department of Neurology, Louisiana State University Health Sciences Center, Shreveport, 1501 Kings Highway, LA 71103, USA.
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2
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Mohammadi S, Seyedmirzaei H, Salehi MA, Jahanshahi A, Zakavi SS, Dehghani Firouzabadi F, Yousem DM. Brain-based Sex Differences in Depression: A Systematic Review of Neuroimaging Studies. Brain Imaging Behav 2023; 17:541-569. [PMID: 37058182 PMCID: PMC10102695 DOI: 10.1007/s11682-023-00772-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/31/2023] [Indexed: 04/15/2023]
Abstract
Major depressive disorder (MDD) is a common psychiatric illness with a wide range of symptoms such as mood decline, loss of interest, and feelings of guilt and worthlessness. Women develop depression more often than men, and the diagnostic criteria for depression mainly rely on female patients' symptoms. By contrast, male depression usually manifests as anger attacks, aggression, substance use, and risk-taking behaviors. Various studies have focused on the neuroimaging findings in psychiatric disorders for a better understanding of their underlying mechanisms. With this review, we aimed to summarize the existing literature on the neuroimaging findings in depression, separated by male and female subjects. A search was conducted on PubMed and Scopus for magnetic resonance imaging (MRI), functional MRI (fMRI), and diffusion tensor imaging (DTI) studies of depression. After screening the search results, 15 MRI, 12 fMRI, and 4 DTI studies were included. Sex differences were mainly reflected in the following regions: 1) total brain, hippocampus, amygdala, habenula, anterior cingulate cortex, and corpus callosum volumes, 2) frontal and temporal gyri functions, along with functions of the caudate nucleus and prefrontal cortex, and 3) frontal fasciculi and frontal projections of corpus callosum microstructural alterations. Our review faces limitations such as small sample sizes and heterogeneity in populations and modalities. But in conclusion, it reflects the possible roles of sex-based hormonal and social factors in the depression pathophysiology.
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Affiliation(s)
- Soheil Mohammadi
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Homa Seyedmirzaei
- School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
- Interdisciplinary Neuroscience Research Program (INRP), Tehran University of Medical Sciences, Tehran, Iran
| | | | - Ali Jahanshahi
- School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Seyed Sina Zakavi
- School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - David M Yousem
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institution, Baltimore, MD, USA.
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3
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Murck H, Lehr L, Jezova D. A viewpoint on aldosterone and BMI related brain morphology in relation to treatment outcome in patients with major depression. J Neuroendocrinol 2023; 35:e13219. [PMID: 36539978 DOI: 10.1111/jne.13219] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 11/06/2022] [Accepted: 11/15/2022] [Indexed: 11/21/2022]
Abstract
An abundance of knowledge has been collected describing the involvement of neuroendocrine parameters in major depression. The hypothalamic-pituitary-adrenocortical (HPA) axis regulating cortisol release has been extensively studied; however, attempts to target the HPA axis pharmacologically to treat major depression have failed. This review focuses on the importance of the adrenocortical stress hormone aldosterone, which is released by adrenocorticotropic hormone and angiotensin, and the mineralocorticoid receptor (MR) in depression. Depressed patients, in particular those with atypical depression, have signs of central hyperactivation of the aldosterone sensitive MR, potentially as a consequence of a reactive aldosterone release induced by low blood pressure and as a result of low sensitivity of peripheral MR. This is reflected in reduced heart rate variability, increased salt appetite and sleep changes in this group of patients. In addition, enlarged brain ventricles, compressed corpus callosum and changes of the choroid plexus are associated with increased aldosterone (in relation to cortisol). Furthermore, subjects with these features often show obesity. These characteristics are related to a worse antidepressant treatment outcome. Alterations in choroid plexus function as a consequence of increased aldosterone levels, autonomic dysregulation, metabolic changes and/or inflammation may be involved. The characterization of this regulatory system is in its early days but may identify new targets for therapeutic interventions.
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Affiliation(s)
- Harald Murck
- Philipps-University Marburg, Marburg, Germany
- Murck-Neuroscience LLC Westfield, Westfield, NJ, USA
| | - Lisa Lehr
- Department of Nephrology, Klinikum Rechts der Isar, Technical University Munich, Munich, Germany
| | - Daniela Jezova
- Slovak Academy of Sciences, Biomedical Research Center, Institute of Experimental Endocrinology, Bratislava, Slovakia
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4
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Jellinger KA. Pathomechanisms of Vascular Depression in Older Adults. Int J Mol Sci 2021; 23:ijms23010308. [PMID: 35008732 PMCID: PMC8745290 DOI: 10.3390/ijms23010308] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/20/2021] [Accepted: 12/24/2021] [Indexed: 02/07/2023] Open
Abstract
Depression in older individuals is a common complex mood disorder with high comorbidity of both psychiatric and physical diseases, associated with high disability, cognitive decline, and increased mortality The factors predicting the risk of late-life depression (LLD) are incompletely understood. The reciprocal relationship of depressive disorder and age- and disease-related processes has generated pathogenic hypotheses and provided various treatment options. The heterogeneity of depression complicates research into the underlying pathogenic cascade, and factors involved in LLD considerably differ from those involved in early life depression. Evidence suggests that a variety of vascular mechanisms, in particular cerebral small vessel disease, generalized microvascular, and endothelial dysfunction, as well as metabolic risk factors, including diabetes, and inflammation that may induce subcortical white and gray matter lesions by compromising fronto-limbic and other important neuronal networks, may contribute to the development of LLD. The "vascular depression" hypothesis postulates that cerebrovascular disease or vascular risk factors can predispose, precipitate, and perpetuate geriatric depression syndromes, based on their comorbidity with cerebrovascular lesions and the frequent development of depression after stroke. Vascular burden is associated with cognitive deficits and a specific form of LLD, vascular depression, which is marked by decreased white matter integrity, executive dysfunction, functional disability, and poorer response to antidepressive therapy than major depressive disorder without vascular risk factors. Other pathogenic factors of LLD, such as neurodegeneration or neuroimmune regulatory dysmechanisms, are briefly discussed. Treatment planning should consider a modest response of LLD to antidepressants, while vascular and metabolic factors may provide promising targets for its successful prevention and treatment. However, their effectiveness needs further investigation, and intervention studies are needed to assess which interventions are appropriate and effective in clinical practice.
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Affiliation(s)
- Kurt A Jellinger
- Institute of Clinical Neurobiology, Alberichgasse 5/13, 1150 Vienna, Austria
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5
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Geraets AF, Köhler S, Jansen JF, Eussen SJ, Stehouwer CDA, Schaper NC, Wesselius A, Verhey FR, Schram MT. The association of markers of cerebral small vessel disease and brain atrophy with incidence and course of depressive symptoms - the maastricht study. J Affect Disord 2021; 292:439-447. [PMID: 34144369 DOI: 10.1016/j.jad.2021.05.096] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 04/29/2021] [Accepted: 05/30/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND Cerebral small vessel disease (CSVD) and neurodegeneration may be involved in the development and persistence of late-life depressive symptoms, but longitudinal evidence is scarce. We investigated the longitudinal associations of markers of CSVD and brain atrophy with incident depressive symptoms and the course of depressive symptoms, above and below 60 years of age. METHODS White matter hyperintensity volumes (WMH), presence of lacunar infarcts and cerebral microbleeds, and white matter, grey matter, and cerebral spinal fluid volumes were assessed at baseline by 3T MRI in The Maastricht Study (mean age 59.5±8.5 years, 49.6% women, n=4,347; 16,535 person-years of follow-up). Clinically relevant depressive symptoms (9-item Patient Health Questionnaire≥10) were assessed at baseline and annually over seven years. We used Cox regression and multinomial logistic regression analyses adjusted for demographic, cardiovascular, and lifestyle risk factors. RESULTS Above 60 years of age, larger WMH volumes were associated with an increased risk for incident depressive symptoms (HR[95%CI]:1.24[1.04;1.48] per SD) and a persistent course of depressive symptoms (OR:1.44[1.04;2.00] per SD). Total CSVD burden was associated with persistent depressive symptoms irrespective of age (adjusted OR:1.58[1.03;2.43]), while no associations were found for general markers of brain atrophy. LIMITATIONSS Our findings need replication in other large-scale population-based studies. CONCLUSIONS Our findings may suggest a temporal association of larger WMH volume with the incidence and persistence of late-life depression in the general population and may provide a potential target for the prevention of chronic late-life depression.
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Affiliation(s)
- Anouk Fj Geraets
- Department of Psychiatry and Neuropsychology; Alzheimer Centrum Limburg, the Netherlands; Department of Internal Medicine; School for Mental Health and Neuroscience; School for Cardiovascular Diseases (CARIM)
| | - Sebastian Köhler
- Department of Psychiatry and Neuropsychology; Alzheimer Centrum Limburg, the Netherlands; School for Mental Health and Neuroscience
| | - Jacobus Fa Jansen
- Department of Radiology and Nuclear Medicine; School for Mental Health and Neuroscience
| | - Simone Jpm Eussen
- Department of Epidemiology; School for Cardiovascular Diseases (CARIM)
| | - Coen DA Stehouwer
- Department of Internal Medicine; School for Cardiovascular Diseases (CARIM)
| | - Nicolaas C Schaper
- Department of Internal Medicine; School for Cardiovascular Diseases (CARIM)
| | - Anke Wesselius
- Department of Genetics & Cell Biology, Complex Genetics, Maastricht University Medical Center (MUMC+), 6202 AZ, Maastricht, Limburg, the Netherlands; School of Nutrition and Translational Research in Metabolism (NUTRIM), Faculty of Health, Medicine & Life Sciences, Maastricht University, 6200 MD, Maastricht, Limburg, the Netherlands
| | - Frans Rj Verhey
- Department of Psychiatry and Neuropsychology; Alzheimer Centrum Limburg, the Netherlands; School for Mental Health and Neuroscience
| | - Miranda T Schram
- Department of Psychiatry and Neuropsychology; Department of Internal Medicine; School for Mental Health and Neuroscience; School for Cardiovascular Diseases (CARIM).
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Zaninotto AL, Grassi DC, Duarte D, Rodrigues PA, Cardoso E, Feltrin FS, Guirado VMDP, Macruz FBDC, Otaduy MCG, da Costa Leite C, Paiva WS, Andrade CS. DTI-derived parameters differ between moderate and severe traumatic brain injury and its association with psychiatric scores. Neurol Sci 2021; 43:1343-1350. [PMID: 34264413 DOI: 10.1007/s10072-021-05455-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 06/29/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND AIM Diffusion tensor imaging (DTI) parameters in the corpus callosum have been suggested to be a biomarker for prognostic outcomes in individuals with diffuse axonal injury (DAI). However, differences between the DTI parameters on moderate and severe trauma in DAI over time are still unclear. A secondary goal was to study the association between the changes in the DTI parameters, anxiety, and depressive scores in DAI over time. METHODS Twenty subjects were recruited from a neurological outpatient clinic and evaluated at 2, 6, and 12 months after the brain injury and compared to matched age and sex healthy controls regarding the DTI parameters in the corpus callosum. State-Trace Anxiety Inventory and Beck Depression Inventory were used to assess psychiatric outcomes in the TBI group over time. RESULTS Differences were observed in the fractional anisotropy and mean diffusivity of the genu, body, and splenium of the corpus callosum between DAI and controls (p < 0.02). Differences in both parameters in the genu of the corpus callosum were also detected between patients with moderate and severe DAI (p < 0.05). There was an increase in the mean diffusivity values and the fractional anisotropy decrease in the DAI group over time (p < 0.02). There was no significant correlation between changes in the fractional anisotropy and mean diffusivity across the study and psychiatric outcomes in DAI. CONCLUSION DTI parameters, specifically the mean diffusivity in the corpus callosum, may provide reliable characterization and quantification of differences determined by the brain injury severity. No correlation was observed with DAI parameters and the psychiatric outcome scores.
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Affiliation(s)
- Ana Luiza Zaninotto
- Speech and Feeding Disorders Lab, MGH Institute of Health Professions (MGHIHP), Boston, MA, USA. .,Department of Neurology, School of Medicine, University São Paulo (USP-SP), São Paulo, SP, Brazil.
| | - Daphine Centola Grassi
- Laboratory of Medical Investigation, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Department of Radiology, Faculdade de Medicina da Universidade de São Paulo, LIM 44 -HCFMUSP, São Paulo, Brazil
| | - Dante Duarte
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, ON, Canada
| | | | - Ellison Cardoso
- Laboratory of Medical Investigation, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Department of Radiology, Faculdade de Medicina da Universidade de São Paulo, LIM 44 -HCFMUSP, São Paulo, Brazil
| | - Fabricio Stewan Feltrin
- Laboratory of Medical Investigation, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Department of Radiology, Faculdade de Medicina da Universidade de São Paulo, LIM 44 -HCFMUSP, São Paulo, Brazil.,Radiology Department, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | - Fabiola Bezerra de Carvalho Macruz
- Laboratory of Medical Investigation, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Department of Radiology, Faculdade de Medicina da Universidade de São Paulo, LIM 44 -HCFMUSP, São Paulo, Brazil
| | - Maria Concepción Garcia Otaduy
- Laboratory of Medical Investigation, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Department of Radiology, Faculdade de Medicina da Universidade de São Paulo, LIM 44 -HCFMUSP, São Paulo, Brazil
| | - Claudia da Costa Leite
- Laboratory of Medical Investigation, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Department of Radiology, Faculdade de Medicina da Universidade de São Paulo, LIM 44 -HCFMUSP, São Paulo, Brazil
| | - Wellingson Silva Paiva
- Department of Neurology, School of Medicine, University São Paulo (USP-SP), São Paulo, SP, Brazil
| | - Celi Santos Andrade
- Laboratory of Medical Investigation, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.,Department of Radiology, Faculdade de Medicina da Universidade de São Paulo, LIM 44 -HCFMUSP, São Paulo, Brazil
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7
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Structural remodeling secondary to functional remodeling in advanced-stage peripheral facial neuritis. Neurol Sci 2020; 41:2453-2460. [PMID: 32206961 DOI: 10.1007/s10072-020-04325-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/02/2020] [Indexed: 01/25/2023]
Abstract
BACKGROUND Structural remodeling is a classic manifestation of disease decompensation. Facial synkinesis is the most troubling sequela of peripheral facial neuritis, and its structural remodeling, especially in white matter (WM), is still poorly understood. Therefore, understanding WM microstructure is important for predicting WM pathology and for early intervention in facial synkinesis patients. METHODS A total of 20 facial synkinesis patients (18 men and 2 women; mean age, 33.35 ± 6.97 years old) and 19 healthy controls (17 men and 2 women; mean age, 33.21 ± 6.75 years old) were enrolled in this study. rs-fMRI data, diffusion tensor imaging (DTI) data, and Beck's Depression Inventory (BDI) data were collected, and tract-based spatial statistics (TBSS) and voxel-mirrored homotopic connectivity (VMHC) values were used to analyze changes in WM microstructure and interhemispheric coordination. RESULTS Compared with the healthy controls, facial synkinesis patients exhibited significantly lower regional fractional anisotropy (FA) in the genu of the corpus callosum and the body of the corpus callosum, significantly higher regional FA in the retrolenticular part of the internal capsule, and significantly decreased VMHC values bilaterally in the orbital inferior frontal gyri, the fusiform gyri, the superior temporal gyri, the superior frontal gyri, and the supplementary motor areas. Furthermore, a lower regional FA in the genu of the corpus callosum was correlated with higher BDI scores in facial synkinesis patients. CONCLUSION Structural remodeling, especially changes in white matter microstructure, may be the central mechanism for severe sequelae of peripheral facial neuritis.
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8
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Shetty AK, Upadhya R, Madhu LN, Kodali M. Novel Insights on Systemic and Brain Aging, Stroke, Amyotrophic Lateral Sclerosis, and Alzheimer's Disease. Aging Dis 2019; 10:470-482. [PMID: 31011489 PMCID: PMC6457051 DOI: 10.14336/ad.2019.0330] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 03/30/2019] [Indexed: 12/11/2022] Open
Abstract
The mechanisms that underlie the pathophysiology of aging, amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD) and stroke are not fully understood and have been the focus of intense and constant investigation worldwide. Studies that provide insights on aging and age-related disease mechanisms are critical for advancing novel therapies that promote successful aging and prevent or cure multiple age-related diseases. The April 2019 issue of the journal, "Aging & Disease" published a series of articles that confer fresh insights on numerous age-related conditions and diseases. The age-related topics include the detrimental effect of overweight on energy metabolism and muscle integrity, senoinflammation as the cause of neuroinflammation, the link between systemic C-reactive protein and brain white matter loss, the role of miR-34a in promoting healthy heart and brain, the potential of sirtuin 3 for reducing cardiac and pulmonary fibrosis, and the promise of statin therapy for ameliorating asymptomatic intracranial atherosclerotic stenosis. Additional aging-related articles highlighted the involvement of miR-181b-5p and high mobility group box-1 in hypertension, Yes-associated protein in cataract formation, multiple miRs and long noncoding RNAs in coronary artery disease development, the role of higher meat consumption on sleep problems, and the link between glycated hemoglobin and depression. The topics related to ALS suggested that individuals with higher education and living in a rural environment have a higher risk for developing ALS, and collagen XIX alpha 1 is a prognostic biomarker of ALS. The topics discussed on AD implied that extracellular amyloid β42 is likely the cause of intraneuronal neurofibrillary tangle accumulation in familial AD and traditional oriental concoctions may be useful for slowing down the progression of AD. The article on stroke suggested that inhibition of the complement system is likely helpful in promoting brain repair after ischemic stroke. The significance of the above findings for understanding the pathogenesis in aging, ALS, AD, and stroke, slowing down the progression of aging, ALS and AD, and promoting brain repair after stroke are discussed.
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Affiliation(s)
- Ashok K. Shetty
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center College of Medicine, College Station, Texas, USA
| | - Raghavendra Upadhya
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center College of Medicine, College Station, Texas, USA
| | - Leelavathi N. Madhu
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center College of Medicine, College Station, Texas, USA
| | - Maheedhar Kodali
- Institute for Regenerative Medicine, Department of Molecular and Cellular Medicine, Texas A&M University Health Science Center College of Medicine, College Station, Texas, USA
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Cyprien F, Courtet P, Maller J, Meslin C, Ritchie K, Ancelin ML, Artero S. Increased Serum C-reactive Protein and Corpus Callosum Alterations in Older Adults. Aging Dis 2019; 10:463-469. [PMID: 31011488 PMCID: PMC6457060 DOI: 10.14336/ad.2018.0329] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 03/29/2018] [Indexed: 01/22/2023] Open
Abstract
Chronic systemic low-grade inflammation is associated with aging, but little is known on whether age-related inflammation affects brain structure, particularly white matter. The current study tested the hypothesis that in older adults without dementia, higher serum levels of high-sensitivity C-reactive protein (hs-CRP) are associated with reduced corpus callosum (CC) areas. French community-dwelling subjects (ESPRIT study) aged 65 and older (N=101) underwent hs-CRP testing and structural magnetic resonance imaging (MRI). Multiple linear regression models were carried out. In the unadjusted model, higher hs-CRP level was significantly associated with smaller anterior, mid, and total midsagittal CC areas, but not with the posterior CC area. These associations were independent of demographic characteristics and intracranial volume. After adjustment for body mass index, diabetes, inflammation-related chronic pathologies and white matter lesions (WML), only the associations between hs-CRP level and smaller anterior and total midsagittal CC areas were still significant, although weaker. These findings suggest that low-grade inflammation is associated with CC structural integrity alterations in older adults independently of physical or neuropsychiatric pathologies.
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Affiliation(s)
- Fabienne Cyprien
- 1INSERM, Univ Montpellier, Neuropsychiatry, Epidemiological and Clinical Research, Montpellier, France.,2CHU Montpellier, F-34095, France
| | - Philippe Courtet
- 1INSERM, Univ Montpellier, Neuropsychiatry, Epidemiological and Clinical Research, Montpellier, France.,2CHU Montpellier, F-34095, France
| | - Jerome Maller
- 3Monash Alfred Psychiatry Research Centre, Central Clinical School, Monash University and Alfred Hospital, Melbourne, Australia
| | - Chantal Meslin
- 4Centre for Research on Ageing, Health and Wellbeing, Research School of Population Health, ANU College of Medicine, Biology and Environment at the Australian National University, Canberra, Australia
| | - Karen Ritchie
- 1INSERM, Univ Montpellier, Neuropsychiatry, Epidemiological and Clinical Research, Montpellier, France
| | - Marie-Laure Ancelin
- 1INSERM, Univ Montpellier, Neuropsychiatry, Epidemiological and Clinical Research, Montpellier, France
| | - Sylvaine Artero
- 1INSERM, Univ Montpellier, Neuropsychiatry, Epidemiological and Clinical Research, Montpellier, France
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Ly M, Andreescu C. Advances and Barriers for Clinical Neuroimaging in Late-Life Mood and Anxiety Disorders. Curr Psychiatry Rep 2018; 20:7. [PMID: 29492705 DOI: 10.1007/s11920-018-0870-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
PURPOSE OF REVIEW Mood and anxiety disorders are very commonly experienced by older adults and are becoming a growing concern due to the rapidly aging global population. Recent advances in neuroimaging may help in improving outcomes in late-life mood and anxiety disorders. The elucidation of mechanisms contributing to late-life mental health disorders may ultimately lead to the identification of novel therapeutic interventions. Alternatively, clinically validated imaging biomarkers may allow for the prediction of treatment response and identification of better therapeutic approaches in late-life mood and anxiety disorders. RECENT FINDINGS In community samples, late-life depression and late-life generalized anxiety disorder occur up to 38 and 15%, respectively, while late-life bipolar disorder is less common and occur in approximately 0.5% of the population. There are significant challenges in treating and improving outcome in late-life mood and anxiety disorders. Time to treatment response and treatment resistance are increased in older adults. Novel neuroimaging techniques have the potential to improve diagnostic and therapeutic outcome in late-life mood and anxiety disorders either through "personalized pharmacotherapy" or through identifying dysfunction regions/networks to be subsequently used for direct interventions such as transcranial magnetic stimulation. This review will provide an overview of recent literature that substantiates the potential role of neuroimaging in clinical practice, as well as the barriers that must be overcome prior to clinical translation.
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Affiliation(s)
- Maria Ly
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, 3811 O'Hara Street, Pittsburgh, PA, USA
| | - Carmen Andreescu
- Department of Psychiatry, Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, 3811 O'Hara Street, Pittsburgh, PA, USA.
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11
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Girgus JS, Yang K, Ferri CV. The Gender Difference in Depression: Are Elderly Women at Greater Risk for Depression Than Elderly Men? Geriatrics (Basel) 2017; 2:geriatrics2040035. [PMID: 31011045 PMCID: PMC6371140 DOI: 10.3390/geriatrics2040035] [Citation(s) in RCA: 129] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/31/2017] [Accepted: 11/02/2017] [Indexed: 12/20/2022] Open
Abstract
Numerous epidemiological reports have found that adolescent, young adult, and middle-aged adult girls and women are more likely to be diagnosed with unipolar depression and report greater symptoms of depression when compared to boys and men of similar ages. What is less well-known is whether this gender difference persists into late life. This literature review examines whether the well-known gender difference in unipolar depression continues into old age, and, if it does, whether the variables that are known to contribute to the gender difference in unipolar depression from adolescence through adulthood continue to contribute to the gender difference in the elderly, and/or whether there are new variables that arise in old age and contribute to the gender difference in the elderly. In this review of 85 empirical studies from every continent except for Antarctica, we find substantial support for the gender difference in depression in individuals who are 60 and older. More research is necessary to determine which factors are the strongest predictors of the gender difference in depression in late life, and particularly whether the factors that seem to be responsible for the gender difference in depression in earlier life stages continue to predict the gender difference in the elderly, and/or whether new factors come into play in late life. Longitudinal research, meta-analyses, and model-based investigations of predictors of the gender difference in depression are needed to provide insights into how and why the gender difference in depression persists in older age.
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Affiliation(s)
- Joan S Girgus
- Department of Psychology, Princeton University, Princeton, NJ 08540, USA.
| | - Kaite Yang
- School of Social and Behavioral Sciences, Stockton University, 101 Vera King Farris Drive, Galloway, NJ 08205, USA.
| | - Christine V Ferri
- School of Social and Behavioral Sciences, Stockton University, 101 Vera King Farris Drive, Galloway, NJ 08205, USA.
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Emsell L, Adamson C, De Winter FL, Billiet T, Christiaens D, Bouckaert F, Adamczuk K, Vandenberghe R, Seal ML, Sienaert P, Sunaert S, Vandenbulcke M. Corpus callosum macro and microstructure in late-life depression. J Affect Disord 2017; 222:63-70. [PMID: 28672181 DOI: 10.1016/j.jad.2017.06.063] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 05/31/2017] [Accepted: 06/26/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND Differences in corpus callosum (CC) morphology and microstructure have been implicated in late-life depression and may distinguish between late and early-onset forms of the illness. However, a multimodal approach using complementary imaging techniques is required to disentangle microstructural alterations from macrostructural partial volume effects. METHODS 107 older adults were assessed: 55 currently-depressed patients without dementia and 52 controls without cognitive impairment. We investigated group differences and clinical associations in 7 sub-regions of the mid-sagittal corpus callosum using T1 anatomical data, white matter hyperintensity (WMH) quantification and two different diffusion MRI (dMRI) models (multi-tissue constrained spherical deconvolution, yielding apparent fibre density, AFD; and diffusion tensor imaging, yielding fractional anisotropy, FA and radial diffusivity, RD). RESULTS Callosal AFD was lower in patients compared to controls. There were no group differences in CC thickness, surface area, FA, RD, nor whole brain or WMH volume. Late-onset of depression was associated with lower FA, higher RD and lower AFD. There were no associations between any imaging measures and psychotic features or depression severity as assessed by the geriatric depression scale. WMH volume was associated with lower FA and AFD, and higher RD in patients. LIMITATIONS Patients were predominantly treatment-resistant. Measurements were limited to the mid-sagittal CC. dMRI analysis was performed on a smaller cohort, n=77. AFD was derived from low b-value data. CONCLUSIONS Callosal structure is largely preserved in LLD. WMH burden may impact on CC microstructure in late-onset depression suggesting vascular pathology has additional deleterious effects in these patients.
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Affiliation(s)
- Louise Emsell
- Old Age Psychiatry, University Psychiatric Centre (UPC) - KU Leuven, Belgium; Translational MRI & Radiology, KU Leuven & University Hospital Leuven, Belgium.
| | - Christopher Adamson
- Developmental Imaging, Murdoch Children's Research Institute, Victoria, Australia
| | | | - Thibo Billiet
- Translational MRI & Radiology, KU Leuven & University Hospital Leuven, Belgium
| | - Daan Christiaens
- Department of Electrical Engineering (ESAT), Processing of Speech and Images (PSI), Medical Image Computing, KU Leuven & Medical Imaging Research Center, University Hospital Leuven, Belgium; Division of Imaging Sciences and Biomedical Engineering, Kings College London, UK
| | - Filip Bouckaert
- Old Age Psychiatry, University Psychiatric Centre (UPC) - KU Leuven, Belgium; KU Leuven, University Psychiatric Center KU Leuven, Academic Center for ECT and Neurostimulation (AcCENT), Kortenberg, Belgium
| | - Katarzyna Adamczuk
- Laboratory for Cognitive Neurology, Department of Neurology, KU Leuven & University Hospital Leuven, Belgium; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, USA
| | - Rik Vandenberghe
- Laboratory for Cognitive Neurology, Department of Neurology, KU Leuven & University Hospital Leuven, Belgium
| | - Marc L Seal
- Developmental Imaging, Murdoch Children's Research Institute, Victoria, Australia; Department of Paediatrics, The University of Melbourne, Victoria, Australia
| | - Pascal Sienaert
- KU Leuven, University Psychiatric Center KU Leuven, Academic Center for ECT and Neurostimulation (AcCENT), Kortenberg, Belgium
| | - Stefan Sunaert
- Translational MRI & Radiology, KU Leuven & University Hospital Leuven, Belgium
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Wang R, Wilkinson M, Kane T, Takahashi E. Convergence of Cortical, Thalamocortical, and Callosal Pathways during Human Fetal Development Revealed by Diffusion MRI Tractography. Front Neurosci 2017; 11:576. [PMID: 29163000 PMCID: PMC5671991 DOI: 10.3389/fnins.2017.00576] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 10/02/2017] [Indexed: 11/17/2022] Open
Abstract
There has been evidence that during brain development, emerging thalamocortical (TC) and corticothalamic (CT) pathways converge in some brain regions and follow each other's trajectories to their final destinations. Corpus callosal (CC) pathways also emerge at a similar developmental stage, and are known to converge with TC pathways in specific cortical regions in mature brains. Given the functional relationships between TC and CC pathways, anatomical convergence of the two pathways are likely important for their functional integration. However, it is unknown (1) where TC and CT subcortically converge in the human brain, and (2) where TC and CC converge in the cortex of the human brain, due to the limitations of non-invasive methods. The goals of this study were to describe the spatio-temporal relationships in the development of the TC/CT and CC pathways in the human brain, using high-angular resolution diffusion MR imaging (HARDI) tractography. Emerging cortical, TC and CC pathways were identified in postmortem fetal brains ranging from 17 gestational weeks (GW) to 30 GW, as well as in vivo 34-40 GW newborns. Some pathways from the thalami were found to be converged with pathways from the cerebral cortex as early as 17 GW. Such convergence was observed mainly in anterior and middle regions of the brain until 21 GW. At 22 GW and onwards, posterior pathways from the thalami also converged with cortical pathways. Many CC pathways reached the full length up to the cortical surface as early as 17 GW, while pathways linked to thalami (not only TC axons but also including pathways linked to thalamic neuronal migration) reached the cortical surface at and after 20 GW. These results suggest that CC pathways developed earlier than the TC pathways. The two pathways were widespread at early stages, but by 40 GW they condensed and formed groups of pathways that projected to specific regions of the cortex and overlapped in some brain regions. These results suggest that HARDI tractography has the potential to identify developing TC/CT and CC pathways with the timing and location of their convergence in fetal stages persisting in postnatal development.
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Affiliation(s)
- Rongpin Wang
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States
- Department of Radiology, Guizhou Provincial People's Hospital, Guiyang, China
| | - Molly Wilkinson
- Department of Behavioral Neuroscience, Northeastern University, Boston, MA, United States
| | - Tara Kane
- Department of Behavioral Neuroscience, Northeastern University, Boston, MA, United States
| | - Emi Takahashi
- Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA, United States
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van Agtmaal MJM, Houben AJHM, Pouwer F, Stehouwer CDA, Schram MT. Association of Microvascular Dysfunction With Late-Life Depression: A Systematic Review and Meta-analysis. JAMA Psychiatry 2017; 74:729-739. [PMID: 28564681 PMCID: PMC5710252 DOI: 10.1001/jamapsychiatry.2017.0984] [Citation(s) in RCA: 188] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 03/26/2017] [Indexed: 12/14/2022]
Abstract
Importance The etiologic factors of late-life depression are still poorly understood. Recent evidence suggests that microvascular dysfunction is associated with depression, which may have implications for prevention and treatment. However, this association has not been systematically reviewed. Objective To examine the associations of peripheral and cerebral microvascular dysfunction with late-life depression. Data Sources A systematic literature search was conducted in MEDLINE and EMBASE for and longitudinal studies published since inception to October 16, 2016, that assessed the associations between microvascular dysfunction and depression. Study Selection Three independent researchers performed the study selection based on consensus. Inclusion criteria were a study population 40 years of age or older, a validated method of detecting depression, and validated measures of microvascular function. Data Extraction and Synthesis This systematic review and meta-analysis has been registered at PROSPERO (CRD42016049158) and is reported in accordance with the PRISMA and MOOSE guidelines. Data extraction was performed by an independent researcher. Main Outcomes and Measures The following 5 estimates of microvascular dysfunction were considered in participants with or without depression: plasma markers of endothelial function, albuminuria, measurements of skin and muscle microcirculation, retinal arteriolar and venular diameter, and markers for cerebral small vessel disease. Data are reported as pooled odds ratios (ORs) by use of the generic inverse variance method with the use of random-effects models. Results A total of 712 studies were identified; 48 were included in the meta-analysis, of which 8 described longitudinal data. Data from 43 600 participants, 9203 individuals with depression, and 72 441 person-years (mean follow-up, 3.7 years) were available. Higher levels of plasma endothelial biomarkers (soluble intercellular adhesion molecule-1: OR, 1.58; 95% CI, 1.28-1.96), white matter hyperintensities (OR, 1.29; 95% CI, 1.19-1.39), cerebral microbleeds (OR, 1.18; 95% CI, 1.03-1.34), and cerebral (micro)infarctions (OR, 1.30; 95% CI, 1.21-1.39) were associated with depression. Among the studies available, no significant associations of albuminuria and retinal vessel diameters with depression were reported. Longitudinal data showed a significant association of white matter hyperintensities with incident depression (OR, 1.19; 95% CI, 1.09-1.30). Conclusions and Relevance This meta-analysis shows that both the peripheral and cerebral forms of microvascular dysfunction are associated with higher odds of (incident) late-life depression. This finding may have clinical implications because microvascular dysfunction might provide a potential target for the prevention and treatment of depression.
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Affiliation(s)
- Marnix J. M. van Agtmaal
- Department of Internal Medicine, Maastricht University Medical Centre, Maastricht, the Netherlands
- Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands
| | - Alfons J. H. M. Houben
- Department of Internal Medicine, Maastricht University Medical Centre, Maastricht, the Netherlands
- Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands
| | - Frans Pouwer
- Department of Psychology, University of Southern Denmark, Odense, Denmark
| | - Coen D. A. Stehouwer
- Department of Internal Medicine, Maastricht University Medical Centre, Maastricht, the Netherlands
- Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands
| | - Miranda T. Schram
- Department of Internal Medicine, Maastricht University Medical Centre, Maastricht, the Netherlands
- Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands
- Heart and Vascular Center, Maastricht University Medical Center, Maastricht, the Netherlands
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Chen VCH, Shen CY, Liang SHY, Li ZH, Tyan YS, Liao YT, Huang YC, Lee Y, McIntyre RS, Weng JC. Assessment of abnormal brain structures and networks in major depressive disorder using morphometric and connectome analyses. J Affect Disord 2016; 205:103-111. [PMID: 27423425 DOI: 10.1016/j.jad.2016.06.066] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Revised: 06/14/2016] [Accepted: 06/15/2016] [Indexed: 01/11/2023]
Abstract
BACKGROUND It is hypothesized that the phenomenology of major depressive disorder (MDD) is subserved by disturbances in the structure and function of brain circuits; however, findings of structural abnormalities using MRI have been inconsistent. Generalized q-sampling imaging (GQI) methodology provides an opportunity to assess the functional integrity of white matter tracts in implicated circuits. METHODS The study population was comprised of 16 outpatients with MDD (mean age 44.81±2.2 years) and 30 age- and gender-matched healthy controls (mean age 45.03±1.88 years). We excluded participants with any other primary mental disorder, substance use disorder, or any neurological illnesses. We used T1-weighted 3D MRI with voxel-based morphometry (VBM) and vertex-wise shape analysis, and GQI with voxel-based statistical analysis (VBA), graph theoretical analysis (GTA) and network-based statistical (NBS) analysis to evaluate brain structure and connectivity abnormalities in MDD compared to healthy controls correlates with clinical measures of depressive symptom severity, Hamilton Depression Rating Scale 17-item (HAMD) and Hospital Anxiety and Depression Scale (HADS). RESULTS Using VBM and vertex-wise shape analyses, we found significant volumetric decreases in the hippocampus and amygdala among subjects with MDD (p<0.001). Using GQI, we found decreases in diffusion anisotropy in the superior longitudinal fasciculus and increases in diffusion probability distribution in the frontal lobe among subjects with MDD (p<0.01). In GTA and NBS analyses, we found several disruptions in connectivity among subjects with MDD, particularly in the frontal lobes (p<0.05). In addition, structural alterations were correlated with depressive symptom severity (p<0.01). LIMITATIONS Small sample size; the cross-sectional design did not allow us to observe treatment effects in the MDD participants. CONCLUSIONS Our results provide further evidence indicating that MDD may be conceptualized as a brain disorder with abnormal circuit structure and connectivity.
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Affiliation(s)
- Vincent Chin-Hung Chen
- School of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Psychiatry, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Chao-Yu Shen
- Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan; Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Sophie Hsin-Yi Liang
- School of Medicine, Chang Gung University, Taoyuan, Taiwan; Department of Psychiatry, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Zhen-Hui Li
- Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan
| | - Yeu-Sheng Tyan
- Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan; Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Yin-To Liao
- Department of Psychiatry, Chung Shan Medical University, Taichung, Taiwan
| | - Yin-Chen Huang
- Department of Neurosurgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Yena Lee
- Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Canada
| | - Roger S McIntyre
- Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada
| | - Jun-Cheng Weng
- Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan; Department of Medical Imaging, Chung Shan Medical University Hospital, Taichung, Taiwan.
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Hofer S, Wang X, Roeloffs V, Frahm J. Single-shot T1 mapping of the corpus callosum: a rapid characterization of fiber bundle anatomy. Front Neuroanat 2015; 9:57. [PMID: 26029059 PMCID: PMC4426710 DOI: 10.3389/fnana.2015.00057] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 04/23/2015] [Indexed: 11/23/2022] Open
Abstract
Using diffusion-tensor magnetic resonance imaging and fiber tractography the topographic organization of the human corpus callosum (CC) has been described to comprise five segments with fibers projecting into prefrontal (I), premotor and supplementary motor (II), primary motor (III), and primary sensory areas (IV), as well as into parietal, temporal, and occipital cortical areas (V). In order to more rapidly characterize the underlying anatomy of these segments, this study used a novel single-shot T1 mapping method to quantitatively determine T1 relaxation times in the human CC. A region-of-interest analysis revealed a tendency for the lowest T1 relaxation times in the genu and the highest T1 relaxation times in the somatomotor region of the CC. This observation separates regions dominated by myelinated fibers with large diameters (somatomotor area) from densely packed smaller axonal bundles (genu) with less myelin. The results indicate that characteristic T1 relaxation times in callosal profiles provide an additional means to monitor differences in fiber anatomy, fiber density, and gray matter in respective neocortical areas. In conclusion, rapid T1 mapping allows for a characterization of the axonal architecture in an individual CC in less than 10 s. The approach emerges as a valuable means for studying neocortical brain anatomy with possible implications for the diagnosis of neurodegenerative processes.
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Affiliation(s)
- Sabine Hofer
- Biomedizinische NMR Forschungs GmbH, Max-Planck-Institut für Biophysikalische Chemie Göttingen, Germany ; Bernstein Center for Computational Neuroscience Göttingen, Germany
| | - Xiaoqing Wang
- Biomedizinische NMR Forschungs GmbH, Max-Planck-Institut für Biophysikalische Chemie Göttingen, Germany
| | - Volkert Roeloffs
- Biomedizinische NMR Forschungs GmbH, Max-Planck-Institut für Biophysikalische Chemie Göttingen, Germany
| | - Jens Frahm
- Biomedizinische NMR Forschungs GmbH, Max-Planck-Institut für Biophysikalische Chemie Göttingen, Germany ; Bernstein Center for Computational Neuroscience Göttingen, Germany
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