Tag: neuroinflammation

Research teams find widespread inflammation in the brains of fibromyalgia patients

A study by Massachusetts General Hospital (MGH) researchers – collaborating with a team at the Karolinska Institutet in Sweden – has documented for the first time widespread inflammation in the brains of patients with the poorly understood condition called fibromyalgia. Their report has been published online in the journal Brain, Behavior and Immunity.

“We don’t have good treatment options for fibromyalgia, so identifying a potential treatment target could lead to the development of innovative, more effective therapies,” says Marco Loggia, PhD, of the MGH-based Martinos Center for Biomedical Imaging, co-senior author of the report. “And finding objective neurochemical changes in the brains of patients with fibromyalgia should help reduce the persistent stigma that many patients face, often being told their symptoms are imaginary and there’s nothing really wrong with them.”

Characterized by symptoms including chronic widespread pain, sleep problems, fatigue, and problems with thinking and memory, fibromyalgia affects around 4 million adults in the U.S., according to the Centers for Disease Control and Prevention. Previous research from the Karolinska group led by Eva Kosek, MD, PhD, co-senior author of the current study, suggested a potential role for neuroinflammation in the condition – including elevated levels of inflammatory proteins in the cerebrospinal fluid – but no previous study has directly visualized neuroinflammation in fibromyalgia patients.

A 2015 study by Loggia’s team used combined MR/PET scanning to document neuroinflammation – specifically activation of glial cells – in the brains of patients with chronic back pain. Hypothesizing that similar glial activation might be found in fibromyalgia patients as well, his team used the same PET radiopharmaceutical, which binds to the translocator protein (TSPO) that is overexpressed by activated glial cells, in their study enrolling 20 fibromyalgia patients and 14 control volunteers.

At the same time, Kosek’s team at Karolinska had enrolled a group of 11 patients and an equal number of control participants for a similar study with the TSPO-binding PET tracer. Since that radiopharmaceutical binds to two types of glial cells – microglia and astrocytes – they also imaged 11 patients, 6 who had the TSPO imaging and 5 others, and another 11 controls with a PET tracer that is thought to bind preferentially to astrocytes and not to microglia. At both centers, participants with fibromyalgia completed questionnaires to assess their symptoms. When the MGH team became aware of the similar investigation the Karolinska group had underway, the teams decided to combine their data into a single study.

The results from both centers found that glial activation in several regions of the brains of fibromyalgia patients was significantly greater than it was in control participants. Compared to the MGH team’s chronic back pain study, TSPO elevations were more widespread throughout the brain, which Loggia indicates corresponds to the more complex symptom patterns of fibromyalgia. TSPO levels in a structure called the cingulate gyrus – an area associated with emotional processing where neuroinflammation has been reported in patients with chronic fatigue syndrome – corresponded with patients reported levels of fatigue. The Karolinska team’s studies with the astrocyte-binding tracer found little difference between patients and controls, suggesting that microglia were primarily responsible for the increased neuro-inflammation in fibromyalgia patients.

“The activation of glial cells we observed in our studies releases inflammatory mediators that are thought to sensitize pain pathways and contribute to symptoms such as fatigue,” says Loggia, an assistant professor of Radiology at Harvard Medical School. “The ability to join forces with our colleagues at Karolinska was fantastic, because combining our data and seeing similar results at both sites gives confidence to the reliability of our results.”

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The co-lead authors of the Brain, Behavior and Immunity report are Daniel Albrecht, PhD, MGH Martinos Center and Department of Radiology, and Anton Forsberg, PhD, Karolinska Institutet. Support for the study includes U.S. Department of Defense grant W81XWH-14-1-0543; National Institutes of Health grants R01 NS094306-01A1, R01 NS095937-01A1 and R21 NS087472-01A1; an International Association for the Study of Pain Early Career Award, and funding from the Stockholm County Council the Swedish Research Council, the Swedish Rheumatism Association and the Fibromyalgia Association of Sweden.

Massachusetts General Hospital, founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH Research Institute conducts the largest hospital-based research program in the nation, with an annual research budget of more than $900 million and major research centers in HIV/AIDS, cardiovascular research, cancer, computational and integrative biology, cutaneous biology, genomic medicine, medical imaging, neurodegenerative disorders, regenerative medicine, reproductive biology, systems biology, photomedicine and transplantation biology. The MGH topped the 2015 Nature Index list of health care organizations publishing in leading scientific journals and earned the prestigious 2015 Foster G. McGaw Prize for Excellence in Community Service. In August 2018 the MGH was once again named to the Honor Roll in the U.S. News & World Report list of “America’s Best Hospitals.”

Neuroinflammation in the Brain of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is characterized by chronic, profound, disabling, and unexplained fatigue; cognitive impairment; and chronic widespread pain. By using positron emission tomography, our study demonstrated neuroinflammation in the brain of patients with ME/CFS. Neuroinflammation was found to be widespread in the brain areas of the patients with ME/CFS and was associated with the severity of their neuropsychological symptoms. The ongoing research would lead to the establishment of objective diagnostic criteria and development of an appropriate therapy.

Source: Nakatomi Y1, Kuratsune H, Watanabe Y. Neuroinflammation in the Brain of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Brain Nerve. 2018 Jan;70(1):19-25. doi: 10.11477/mf.1416200945. [Article in Japanese] https://www.ncbi.nlm.nih.gov/pubmed/29348371

History of Researches on Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disease characterized by chronic, profound, disabling, and unexplained fatigue. The first patient with ME/CFS in Japan was identified and described in 1990 by Prof. Teruo Kitani and Dr. Hirohiko Kuratsune of the Research Institute for Microbial Diseases, Osaka University. Since then, a variety of studies have been performed to determine the objective biomarkers of the disease. Although it is hypothesized that brain inflammation is involved in the pathophysiology of ME/CFS, there is to date no direct evidence of neuroinflammation in patients with ME/CFS. Our recent positron emission tomography study successfully demonstrated that microglial activation, which is linked to neuroinflammation, occurs in widespread brain areas in patients with ME/CFS, and is associated with the severity of the neuropsychological symptoms. Thus, evaluation of neuroinflammation in patients with ME/CFS may be essential for understanding the core pathophysiology of the disease, and for developing objective diagnostic criteria and effective medical treatments for ME/CFS. Here, we describe disease-related pathophysiological findings and topics, and discuss the history of the diagnostic and therapeutic attempts based on previous findings in Japan.

Source: Watanabe Y, Kuratsune H. History of Researches on Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Brain Nerve. 2018 Jan;70(1):5-9. doi: 10.11477/mf.1416200943. [Article in Japanese] https://www.ncbi.nlm.nih.gov/pubmed/29348369

The Neuroinflammatory Etiopathology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating multi-systemic chronic illness of unknown etiology, classified as a neurological disorder by the World Health Organization (WHO). The symptomatology of the condition appears to emanate from a variety of sources of chronic neurological disturbance and associated distortions, and chronicity, in noxious sensory signaling and neuroimmune activation. This article incorporates a summary review and discussion of biomedical research considered relevant to this essential conception perspective. It is intended to provide stakeholders with a concise, integrated outline disease model in order to help demystify this major public health problem. The primary etiopathological factors presented are:

(A) Postural/biomechanical pain signaling, affecting adverse neuroexcitation, in the context of compression, constriction, strain, or damage of vertebral-regional bone and neuromuscular tissues;

(B) Immune mediated inflammatory sequelae, in the context of prolonged immunotropic neurotrophic infection-with lymphotropic/gliotropic/glio-toxic varieties implicated in particular;

(C) A combination of factors A and B. Sustained glial activation under such conditions is associated with oxidative and nitrosative stress, neuroinflammation, and neural sensitivity. These processes collectively enhance the potential for multi-systemic disarray involving endocrine pathway aberration, immune and mitochondrial dysfunction, and neurodegeneration, and tend toward still more intractable synergistic neuro-glial dysfunction (gliopathy), autoimmunity, and central neuronal sensitization.

 

Source: Glassford JA. The Neuroinflammatory Etiopathology of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Front Physiol. 2017 Feb 17;8:88. doi: 10.3389/fphys.2017.00088. eCollection 2017. http://journal.frontiersin.org/article/10.3389/fphys.2017.00088/full (Full article)

 

Brain imaging reveals clues about chronic fatigue syndrome

A brain imaging study shows that patients with chronic fatigue syndrome may have reduced responses, compared with healthy controls, in a region of the brain connected with fatigue. The findings suggest that chronic fatigue syndrome is associated with changes in the brain involving brain circuits that regulate motor activity and motivation.

Compared with healthy controls, patients with chronic fatigue syndrome had less activation of the basal ganglia, as measured by fMRI (functional magnetic resonance imaging). This reduction of basal ganglia activity was also linked with the severity of fatigue symptoms.

According to the Centers for Disease Control and Prevention, chronic fatigue syndrome is a debilitating and complex disorder characterized by intense fatigue that is not improved by bed rest and that may be worsened by exercise or mental stress.

The results are scheduled for publication in the journal PLOS One.

“We chose the basal ganglia because they are primary targets of inflammation in the brain,” says lead author Andrew Miller, MD. “Results from a number of previous studies suggest that increased inflammation may be a contributing factor to fatigue in CFS patients, and may even be the cause in some patients.”

Miller is William P. Timmie professor of psychiatry and behavioral sciences at Emory University School of Medicine. The study was a collaboration among researchers at Emory University School of Medicine, the CDC’s Chronic Viral Diseases Branch, and the University of Modena and Reggio Emilia in Italy. The study was funded by the CDC.

The basal ganglia are structures deep within the brain, thought to be responsible for control of movements and responses to rewards as well as cognitive functions. Several neurological disorders involve dysfunction of the basal ganglia, including Parkinson’s disease and Huntington’s disease, for example.

In previous published studies by Emory researchers, people taking interferon alpha as a treatment for hepatitis C, which can induce severe fatigue, also show reduced activity in the basal ganglia. Interferon alpha is a protein naturally produced by the body, as part of the inflammatory response to viral infection. Inflammation has also been linked to fatigue in other groups such as breast cancer survivors.

“A number of previous studies have suggested that responses to viruses may underlie some cases of CFS,” Miller says. “Our data supports the idea that the body’s immune response to viruses could be associated with fatigue by affecting the brain through inflammation. We are continuing to study how inflammation affects the basal ganglia and what effects that has on other brain regions and brain function. These future studies could help inform new treatments.”

Treatment implications might include the potential utility of medications to alter the body’s immune response by blocking inflammation, or providing drugs that enhance basal ganglia function, he says.

The researchers compared 18 patients diagnosed with chronic fatigue syndrome with 41 healthy volunteers. The 18 patients were recruited [not referred] based on an initial telephone survey followed by extensive clinical evaluations. The clinical evaluations, which came in two phases, were completed by hundreds of Georgia residents. People with major depression or who were taking antidepressants were excluded from the imaging study, although those with anxiety disorders were not.

For the brain imaging portion of the study, participants were told they’d win a dollar if they correctly guessed whether a preselected card was red or black. After they made a guess, the color of the card was revealed, and at that point researchers measured blood flow to the basal ganglia.

The key measurement was: how big is the difference in activity between a win or a loss? Participants’ scores on a survey gauging their levels of fatigue were tied to the difference in basal ganglia activity between winning and losing. Those with the most fatigue had the smallest changes, especially in the right caudate and the right globus pallidus, both parts of the basal ganglia.

Ongoing studies at Emory are further investigating the impact of inflammation on the basal ganglia, including studies using anti-inflammatory treatments to reduce fatigue and loss of motivation in patients with depression and other disorders with inflammation including cancer.

 

Source: Emory Health Sciences. “Brain imaging reveals clues about chronic fatigue syndrome.” ScienceDaily. ScienceDaily, 23 May 2014. https://www.sciencedaily.com/releases/2014/05/140523192427.htm

 

Toward a clearer diagnosis of chronic fatigue syndrome

Researchers at the RIKEN Center for Life Science Technologies, in collaboration with Osaka City University and Kansai University of Welfare Sciences, have used functional PET imaging to show that levels of neuroinflammation, or inflammation of the nervous system, are higher in patients with chronic fatigue syndrome than in healthy people.

Chronic fatigue syndrome, which is also known as myalgic encephalomyelitis, is a debilitating condition characterized by chronic, profound, and disabling fatigue. Unfortunately, the causes are not well understood.

Neuroinflammation — the inflammation of nerve cells — has been hypothesized to be a cause of the condition, but no clear evidence has been put forth to support this idea. Now, in this clinically important study, published in The Journal of Nuclear Medicine, the researchers found that indeed the levels of neuroinflammation markers are elevated in CFS/ME patients compared to the healthy controls.

The researchers performed PET scanning on nine people diagnosed with CFS/ME and ten healthy people, and asked them to complete a questionnaire describing their levels of fatigue, cognitive impairment, pain, and depression. For the PET scan they used a protein that is expressed by microglia and astrocyte cells, which are known to be active in neuroinflammation.

The researchers found that neuroinflammation is higher in CFS/ME patients than in healthy people. They also found that inflammation in certain areas of the brain — the cingulate cortex, hippocampus, amygdala, thalamus, midbrain, and pons — was elevated in a way that correlated with the symptoms, so that for instance, patients who reported impaired cognition tended to demonstrate neuroinflammation in the amygdala, which is known to be involved in cognition. This provides clear evidence of the association between neuroinflammation and the symptoms experienced by patients with CFS/ME.

Though the study was a small one, confirmation of the concept that PET scanning could be used as an objective test for CFS/ME could lead to better diagnosis and ultimately to the development of new therapies to provide relief to the many people around the world afflicted by this condition.

Dr. Yasuyoshi Watanabe, who led the study at RIKEN, stated, “We plan to continue research following this exciting discovery in order to develop objective tests for CFS/ME and ultimately ways to cure and prevent this debilitating disease.”

Journal Reference: Y. Nakatomi, K. Mizuno, A. Ishii, Y. Wada, M. Tanaka, S. Tazawa, K. Onoe, S. Fukuda, J. Kawabe, K. Takahashi, Y. Kataoka, S. Shiomi, K. Yamaguti, M. Inaba, H. Kuratsune, Y. Watanabe. Neuroinflammation in Patients with Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: An 11C-(R)-PK11195 PET Study. Journal of Nuclear Medicine, 2014; DOI:10.2967/jnumed.113.131045

 

Source: RIKEN. “Toward a clearer diagnosis of chronic fatigue syndrome.” ScienceDaily. ScienceDaily, 4 April 2014. https://www.sciencedaily.com/releases/2014/04/140404085538.htm

 

Effect of Milnacipran Treatment on Ventricular Lactate in Fibromyalgia: A Randomized, Double-Blind, Placebo-Controlled Trial

Abstract:

Milnacipran, a serotonin/norepinephrine reuptake inhibitor, has been approved by the US Food and Drug Administration for the treatment of fibromyalgia (FM). This report presents the results of a randomized, double-blind, placebo-controlled trial of milnacipran conducted to test the hypotheses that a) similar to patients with chronic fatigue syndrome, patients with FM have increased ventricular lactate levels at baseline; b) 8 weeks of treatment with milnacipran will lower ventricular lactate levels compared with baseline levels and with ventricular lactate levels after placebo; and c) treatment with milnacipran will improve attention and executive function in the Attention Network Test compared with placebo. In addition, we examined the results for potential associations between ventricular lactate and pain. Baseline ventricular lactate measured by proton magnetic resonance spectroscopic imaging was found to be higher in patients with FM than in healthy controls (F1,37 = 22.11, P < .0001, partial η(2) = .37). Milnacipran reduced pain in patients with FM relative to placebo but had no effect on cognitive processing.

At the end of the study, ventricular lactate levels in the milnacipran-treated group had decreased significantly compared with baseline and after placebo (F1,18 = 8.18, P = .01, partial η(2) = .31). A significantly larger proportion of patients treated with milnacipran showed decreases in both ventricular lactate and pain than those treated with placebo (P = .03). These results suggest that proton magnetic resonance spectroscopic imaging measurements of lactate may serve as a potential biomarker for a therapeutic response in FM and that milnacipran may act, at least in part, by targeting the brain response to glial activation and neuroinflammation.

PERSPECTIVE: Patients treated with milnacipran showed decreases in both pain and ventricular lactate levels compared with those treated with placebo, but, even after treatment, levels of ventricular lactate remained higher than in controls. The hypothesized mechanism for these decreases is via drug-induced reductions of a central inflammatory state.

TRIAL REGISTRATION: ClinicalTrials.gov NCT01108731.

Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

 

Source: Natelson BH, Vu D, Mao X, Weiduschat N, Togo F, Lange G, Blate M, Kang G, Coplan JD, Shungu DC. Effect of Milnacipran Treatment on Ventricular Lactate in Fibromyalgia: A Randomized, Double-Blind, Placebo-Controlled Trial. J Pain. 2015 Nov;16(11):1211-9. doi: 10.1016/j.jpain.2015.08.004. Epub 2015 Aug 31. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4630071/ (Full article)

 

Brain “fog,” inflammation and obesity: key aspects of neuropsychiatric disorders improved by luteolin

Abstract:

Brain “fog” is a constellation of symptoms that include reduced cognition, inability to concentrate and multitask, as well as loss of short and long term memory. Brain “fog” characterizes patients with autism spectrum disorders (ASDs), celiac disease, chronic fatigue syndrome, fibromyalgia, mastocytosis, and postural tachycardia syndrome (POTS), as well as “minimal cognitive impairment,” an early clinical presentation of Alzheimer’s disease (AD), and other neuropsychiatric disorders. Brain “fog” may be due to inflammatory molecules, including adipocytokines and histamine released from mast cells (MCs) further stimulating microglia activation, and causing focal brain inflammation.

Recent reviews have described the potential use of natural flavonoids for the treatment of neuropsychiatric and neurodegenerative diseases. The flavone luteolin has numerous useful actions that include: anti-oxidant, anti-inflammatory, microglia inhibition, neuroprotection, and memory increase. A liposomal luteolin formulation in olive fruit extract improved attention in children with ASDs and brain “fog” in mastocytosis patients. Methylated luteolin analogs with increased activity and better bioavailability could be developed into effective treatments for neuropsychiatric disorders and brain “fog.”

 

Source: Theoharides TC, Stewart JM, Hatziagelaki E, Kolaitis G. Brain “fog,” inflammation and obesity: key aspects of neuropsychiatric disorders improved by luteolin. Front Neurosci. 2015 Jul 3;9:225. doi: 10.3389/fnins.2015.00225. ECollection 2015. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4490655/ (Full article)

 

Neuroinflammation in Patients with Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: An ¹¹C-(R)-PK11195 PET Study

Abstract:

Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a disease characterized by chronic, profound, disabling, and unexplained fatigue. Although it is hypothesized that brain inflammation is involved in the pathophysiology of CFS/ME, there is no direct evidence of neuroinflammation in patients with CFS/ME. Activation of microglia or astrocytes is related to neuroinflammation. (11)C-(R)-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinoline-carboxamide ((11)C-(R)-PK11195) is a ligand of PET for a translocator protein that is expressed by activated microglia or astrocytes. We used (11)C-(R)-PK11195 and PET to investigate the existence of neuroinflammation in CFS/ME patients.

METHODS: Nine CFS/ME patients and 10 healthy controls underwent (11)C-(R)-PK11195 PET and completed questionnaires about fatigue, fatigue sensation, cognitive impairments, pain, and depression. To measure the density of translocator protein, nondisplaceable binding potential (BP(ND)) values were determined using linear graphical analysis with the cerebellum as a reference region.

RESULTS: The BP(ND) values of (11)C-(R)-PK11195 in the cingulate cortex, hippocampus, amygdala, thalamus, midbrain, and pons were 45%-199% higher in CFS/ME patients than in healthy controls. In CFS/ME patients, the BP(ND) values of (11)C-(R)-PK11195 in the amygdala, thalamus, and midbrain positively correlated with cognitive impairment score, the BP(ND) values in the cingulate cortex and thalamus positively correlated with pain score, and the BP(ND) value in the hippocampus positively correlated with depression score.

CONCLUSION: Neuroinflammation is present in widespread brain areas in CFS/ME patients and was associated with the severity of neuropsychologic symptoms. Evaluation of neuroinflammation in CFS/ME patients may be essential for understanding the core pathophysiology and for developing objective diagnostic criteria and effective medical treatments.

© 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

 

Source: Nakatomi Y, Mizuno K, Ishii A, Wada Y, Tanaka M, Tazawa S, Onoe K, Fukuda S, Kawabe J, Takahashi K, Kataoka Y, Shiomi S, Yamaguti K, Inaba M, Kuratsune H, Watanabe Y. Neuroinflammation in Patients with Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: An ¹¹C-(R)-PK11195 PET Study. J Nucl Med. 2014 Jun;55(6):945-50. doi: 10.2967/jnumed.113.131045. Epub 2014 Mar 24. http://jnm.snmjournals.org/content/55/6/945.long (Full article)