J Nucl Med. 2014 Mar 24. [Epub ahead of print]
Neuroinflammation in Patients with Chronic Fatigue Syndrome/Myalgic
Encephalomyelitis: An 11C-(R)-PK11195 PET Study.
Nakatomi Y1, 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.
1Department of Metabolism, Endocrinology and Molecular Medicine, Osaka
City University Graduate School of Medicine, Osaka, Japan.
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.
(11C-(R)-PK11195) is a ligand of PET for a translocator protein that
is expressed by activated microglia or astrocytes. We used
11C-(R)-PK11195 and PET to investigate the existence of
neuroinflammation in CFS/ME patients.
METHODS: Nine CFS/ME patients and 10 healthy controls underwent
11C-(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 (BPND) values were determined using linear graphical
analysis with the cerebellum as a reference region.
RESULTS: The BPND values of 11C-(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 BPND values of 11C-(R)-PK11195 in the amygdala,
thalamus, and midbrain positively correlated with cognitive impairment
score, the BPND values in the cingulate cortex and thalamus positively
correlated with pain score, and the BPND 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.
KEYWORDS: 11C-(R)-PK11195, chronic fatigue syndrome (CFS), myalgic
encephalomyelitis (ME), neuroinflammation, positron emission
PMID: 24665088 [PubMed - as supplied by publisher]