Type I interferons, inflammation, and fatigue in a longitudinal RNA study of women with breast cancer

BACKGROUND

Fatigue is a common side effect of cancer and its treatment and is thought to be driven in part by activation of the proinflammatory cytokine network. However, the cellular and molecular underpinnings of cancer-related fatigue (CRF) have not been determined, nor have immune pathways beyond inflammation been carefully investigated. The goal of this study was to examine the association between CRF and activation of canonical proinflammatory gene regulation pathways and Type I interferon (IFN) signaling pathways in breast cancer patients during and after treatment.

METHODS

Women diagnosed with early-stage breast cancer (n = 181) completed assessments before and after treatment with radiation and/or chemotherapy and at 6, 12, and 18-month post-treatment follow-ups. Assessments included self-reported fatigue (Multidimensional Fatigue Symptom Inventory - Short Form) and expression of pre-specified sets of Type I IFN and pro-inflammatory immune response genes determined from mRNA sequencing of PBMCs. Mixed effect linear models examined changes in fatigue and immune gene expression over time and tested the hypothesis that fatigue would be associated with increased expression of Type I IFN and inflammatory response genes.

RESULTS

There were significant changes in fatigue and immune gene expression across the assessment period; all measures increased from pre- to post-treatment but showed diverging patterns over the follow-up, with declines in fatigue and persistent elevations in Type I IFN and proinflammatory gene expression. In mixed effect linear models, expression of Type I IFN response genes was elevated in association with fatigue across the assessment period, from pre-treatment to 18-month follow-up. In contrast, pro-inflammatory gene expression was associated with fatigue only at 6, 12, and 18-month follow-ups. Analyses controlling for changes in leukocyte subsets continued to show a significant association between fatigue and Type I IFN gene expression but reduced the time-dependent association with pro-inflammatory gene expression to non-significant.

CONCLUSIONS

Results revealed unexpected complexity in the immune underpinnings of CRF and identify a novel role for IFN signaling as a robust contributor to this symptom before, during, and after treatment. Pro-inflammatory gene expression emerged as a predictor of fatigue later in the cancer trajectory, and that effect was primarily accounted for by a concurrent increase in monocyte prevalence.

Screening Single Nucleotide Polymorphisms Predicting the Efficacy of Electroacupuncture for Fatigue Treatment in Patients with Breast Cancer Following Adjuvant Chemotherapy

Chemotherapy-induced fatigue reduces not only the quality of life of patients but also effect their recurrence-free survival rate. Although electroacupuncture can relieve fatigue, it has limited affect on some patients. Therefore, appropriate biomarkers are needed to help screen patients who can benefit from electroacupuncture treatment of fatigue. We conducted this study to explore the predictive ability of SNPs on the efficacy of electroacupuncture in the treatment of fatigue in patients with breast cancer after adjuvant chemotherapy. Our study included breast cancer patients with fatigue after receiving paclitaxel and/or anthracycline based adjuvant chemotherapy. The patients were divided into the electroacupuncture group and the control group. The electroacupuncture treatment group received adjuvant chemotherapy and electroacupuncture treatment, while the control group only received adjuvant chemotherapy, and then compared the fatigue relief degree of two groups. In addition, we used NCBI dbSNP and PharmGKB databases to select fatigue related genes and their SNPs. We collected peripheral blood from the included patients for SNPs typing, and recorded the efficacy of electroacupuncture to analyzed the correlation between different SNPs and therapeutic efficacy. The side effects of electroacupuncture treatment were also recorded. 76 patients in the electroacupuncture group and 48 patients in the control group were enrolled. In the electroacupuncture group, 63 patients (82.9%) experienced moderate to severe fatigue (BFI score > 3). After electroacupuncture treatment, the number of patients with a BFI score of > 3 was 46 (60.5%). Therefore, the fatigue symptoms of 26.9% patients were significantly improved (P < 0.05). In the control group, which did not receive electroacupuncture treatment, 40 of 48 patients had a BFI score of > 3. Following the same observation time used in the electroacupuncture group, 36 patients had a BFI score of > 3 points. Thus, fatigue was not significantly relieved in the control group (83.3% vs. 75.0%, P > 0.05). We included 56 patients in our analysis of the correlation between SNPs and electroacupuncture treatment effects. We divided the patients into an effective group and ineffective group according to therapeutic effects. Our results indicated that the effective rate of electroacupuncture treatment with IL1A rs3783550 AC and CC genotypes was higher than that with other genotypes (AC: 84.6%, CC: 81.8%, AA: 33.0%, P < 0.05). Similarly, the effective rate of electroacupuncture treatment with HTR1A rs6295 GG and CC genotypes was higher than that with other genotypes (GG: 63.0%, CC: 55.6%, GC: 18.2%, P < 0.05). However, no other genotypes were related to the effect of electroacupuncture treatment on fatigue. Our result showed that electroacupuncture has therapeutic effect on fatigue after adjuvant chemotherapy for breast cancer and the side effects are tolerable. In addition, IL1A rs3763550 and HTR1A rss6295 can predict the therapeutic effect of electroacupuncture on fatigue after adjuvant chemotherapy in breast cancer, which helps to better screen patients who can benefit from electroacupuncture treatment.

Associations of Germline Genetic Variants With Depression and Fatigue Among Hematologic Cancer Patients Treated With Allogeneic Hematopoietic Cell Transplantation

OBJECTIVE

Depression and fatigue are common among cancer patients and are associated with germline genetic variation. The goal of this pilot study was to examine genetic associations with depression and fatigue in the year after allogeneic hematopoietic cell transplant (HCT).

METHODS

Blood was collected from patients and their donors before HCT. Patients completed self-report measures of depression and fatigue before HCT (T1), 90 days post-HCT (T2), and 1 year post-HCT (T3). Of the 384 genetic variants genotyped on a custom Illumina BeadChip microarray, 267 were retained for analysis based on quality control. Main effects of patient and donor variants as well as their interaction were examined using regression analyses. Significant variants were defined as those with a false discovery rate-adjusted p value of <.05.

RESULTS

The sample consisted of 59 patient-donor pairs. Mean levels of depression and fatigue did not change significantly over time ( p values of > .41). Increases in depression from T1 to T2 were associated with patient-donor interactions at rs1928040 ( p = 3.0 × 10 -4 ) and rs6311 ( p = 2.0 × 10 -4 ) in HTR2A . Increases in fatigue from T1 to T2 were associated with patient rs689021 in SORL1 ( p = 6.0 × 10 -5 ) and a patient-donor interaction at rs1885884 in HTR2A ( p < 1.0 × 10 -4 ).

CONCLUSIONS

Data suggest that variants in genes regulating the serotonergic system ( HTR2A ) and lipid metabolism ( SORL1 ) are associated with changes in depression and fatigue in allogeneic HCT patients, implicating patients' own genetic inheritance as well as that of donors. Additional studies are warranted to confirm these findings.

Circulating short chain fatty acids and fatigue in patients with head and neck cancer: A longitudinal prospective study

Fatigue among patients with head and neck cancer (HNC) has been associated with higher inflammation. Short-chain fatty acids (SCFAs) have been shown to have anti-inflammatory and immunoregulatory effects. Therefore, this study aimed to examine the association between SCFAs and fatigue among patients with HNC undergoing treatment with radiotherapy with or without concurrent chemotherapy. Plasma SCFAs and the Multidimensional Fatigue Inventory-20 were collected prior to and one month after the completion of treatment in 59 HNC patients. The genome-wide gene expression profile was obtained from blood leukocytes prior to treatment. Lower butyrate concentrations were significantly associated with higher fatigue (p = 0.013) independent of time of assessment, controlling for covariates. A similar relationship was observed for iso/valerate (p = 0.025). Comparison of gene expression in individuals with the top and bottom 33% of butyrate or iso/valerate concentrations prior to radiotherapy revealed 1,088 and 881 significantly differentially expressed genes, respectively (raw p < 0.05). The top 10 Gene Ontology terms from the enrichment analyses revealed the involvement of pathways related to cytokines and lipid and fatty acid biosynthesis. These findings suggest that SCFAs may regulate inflammatory and immunometabolic responses and, thereby, reduce inflammatory-related symptoms, such as fatigue.

Exploring causal effects of smoking and alcohol related lifestyle factors on self-report tiredness: A Mendelian randomization study

Self-reported tiredness or low energy, often referred to as fatigue, has been linked to lifestyle factors, although data from randomized-controlled trials are lacking. We investigate whether modifiable lifestyle factors including smoking and alcohol intake related exposures (SAIEs) are causal factors for fatigue using Mendelian randomization (MR). A two-sample MR study was performed by using genome-wide association summary results from UK Biobank (UKBB), and each of the sample size is more than 100,000. We used the inverse variance weighted method, and sensitivity analyses (MR Egger, weighted median, penalized median estimators, and multivariable MR) to account for pleiotropy. The two-sample MR analyses showed inverse causal effect of never-smoking status and positive effect of current smoking status on the risk of fatigue. Similarly, genetically predicted alcoholic intake was positively associated with fatigue. The results were consistent across the different MR methods. Our Mendelian randomization analyses do support that the cessation of smoking and alcohol can decrease the risk of fatigue, and limit alcohol intake frequency can also reduce the risk.

Association of leukocyte telomere length with perceived physical fatigability

BACKGROUND

Leukocyte telomere length (LTL) is a potential genomic marker of biological aging, but its relation to fatigability, a prognostic indicator of phenotypic aging (e.g., functional decline) is unknown. We hypothesized shorter LTL would predict greater perceived physical fatigability, but that this association would be attenuated by adjusting for chronological age.

METHODS

Two generations of participants (N = 1997; 309 probands, 1688 offspring) were from the Long Life Family Study (age = 73.7 ± 10.4, range 60-108, 54.4 % women), a longitudinal cohort study of aging. LTL was assayed at baseline. Perceived physical fatigability was measured 8.0 ± 1.1 years later using the validated, self-administered 10-item Pittsburgh Fatigability Scale (PFS, 0-50, higher scores = greater fatigability). Generalized estimating equations were generated to model the association between LTL and PFS Physical scores.

RESULTS

Prevalence of greater physical fatigability (PFS scores≥15) was 41.9 %. Using generalized estimating equations, a one kilobase pair shorter LTL was associated with higher PFS Physical scores (β = 1.8, p < .0001), accounting for family structure, and adjusting for field center, follow-up time, sex, and follow-up body mass index, physical activity, and chronic health conditions. When age was included as a covariate, the association was fully attenuated (β = 0.1, p = .78).

CONCLUSION

LTL may provide an alternative method for estimating an individual's lifetime exposure to chronic stressors, but does not appear to provide additional information not captured by chronological age. Further research is needed to characterize the interaction between age, LTL, and perceived fatigability, and develop a method of identifying individuals at risk for deleterious aging.

Dietary Supplementation of Octacosanol Improves Exercise-Induced Fatigue and Its Molecular Mechanism

Several publications report that octacosanol (OCT) has different biological functions. This study was designed to evaluate the antifatigue effect and molecular mechanism of octacosanol (200 mg/(kg day)) in forced exercise-induced fatigue models of trained male C57BL/6 mice. Results showed that octacosanol ameliorated the mice's autonomic activities, forelimb grip strength, and swimming endurance, and the levels of liver glycogen (LG), muscle glycogen (MG), blood lactic acid (BLA), lactate dehydrogenase (LDH), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were also regulated. Gene analysis results showed that treatment with OCT upregulated 29 genes, while 38 genes were downregulated in gastrocnemius tissue. Gene ontology (GO) analyses indicated that these genes enriched functions in relation to myofibril, contractile fiber, and calcium-dependent adenosinetriphosphatase (ATPase) activity. Octacosanol supplementation significantly adjusted the messenger RNA (mRNA) and protein expression levels related to fatigue performance. Octacosanol has an observably mitigating effect in exercise-induced fatigue models, and its molecular mechanism may be related to the regulation of tripartite motif-containing 63 (Trim63), periaxin (Prx), calcium voltage-gated channel subunit α1 H (Cacna1h), and myosin-binding protein C (Mybpc3) expression.

Water and alcohol extracts from Diaphragma juglandis on anti-fatigue and antioxidative effects in vitro and vivo

BACKGROUND

To estimate the anti-fatigue and antioxidative effects of water and alcohol extracts from Diaphragma juglandis (DJ), H₂ O₂ -treated HepG2 cells were used as an in vitro model to determine the total antioxidant capacities of these two extracts, and behavioral tests on mice and biochemical assay were performed via in vivo experiments.

RESULTS

The results indicate that both extracts possess remarkable HepG2 protective capacities and were capable of scavenging 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) similar to vitamin C. Furthermore, they could significantly prolong the bar climbing time and force swimming time, as well as decrease the serum urea nitrogen and increase the lactate dehydrogenase level and glycogen content. These extracts could also improve the activities of total antioxidant capacity, malondialdehyde, superoxide dismutase, catalase and glutathione peroxidase.

CONCLUSION

In conclusion, both water and alcohol extracts from DJ showed good performance with respect to anti-fatigue and could be a potential antioxidant additive in the field of functional foods. © 2020 Society of Chemical Industry.

Fear of pain moderates the relationship between self-reported fatigue and methionine allele of catechol-O-methyltransferase gene in patients with fibromyalgia

Previous research has shown a consistent association among genetic factors, psychological symptoms and pain associated with fibromyalgia. However, how these symptoms interact to moderate genetic factors in fibromyalgia has rarely been studied to date. The present research investigates whether psychological symptoms can moderate the effects of catechol-O-methyltransferase on pain and fatigue. A total of 108 women diagnosed with fibromyalgia and 77 healthy control participants took part in the study. Pain, fatigue, and psychological symptoms (anxiety, depression, pain catastrophizing, fear of pain and fear of movement) were measured by self-report questionnaires. Two types of statistical analyses were performed; the first was undertaken to explore the influences of COMT genotypes on clinical symptoms by comparing patients with fibromyalgia and healthy controls. In the second analysis, moderation analyses to explore the role of psychological symptoms as potential factors that moderate the relationship between pain/fatigue and COMT genotypes were performed. The main results indicated that patients carrying the Met/Met genotype reported significantly higher levels of fatigue than heterozygote carriers (i.e., Met/Val genotype) and higher levels of fatigue, but not significantly different, than Val homozygote carriers. Among patients with fibromyalgia carrying methionine alleles (i.e., Met/Met + Met/Val carriers), only those who scored high on medical fear of pain, experienced an intensified feeling of fatigue. Thus, the present research suggests that fear of pain, as a psychological symptom frequently described in fibromyalgia may act as a moderating factor in the relationship between the Met allele of the COMT gene and the increase or decrease in self-reported fatigue. Although further research with wider patient samples is needed to confirm the present findings, these results point out that the use of psychological interventions focused on affective symptomatology might be a useful tool to reduce the severity of fibromyalgia.

Supplementation with embryo chicken egg extract improves exercise performance and exerts anti-fatigue effects via AMPK/mTOR signalling pathway in mice

BACKGROUND

Embryo chicken egg is a nutritional supplement that has been used to enhance physical fitness and promote wound healing according to traditional Chinese medicine for many years. In this study, we evaluated the effects of embryo chicken egg extract (ECE) on the exercise performance and fatigue in mice and the underlying mechanisms.

RESULTS

The results indicated that ECE can prolong the exhaustive swimming time, decrease lactic acid, blood urea nitrogen, creatine kinase, and malondialdehyde levels, and increase superoxide dismutase, glutathione peroxidase, and glycogen levels. Additionally, ECE can also regulate the balance of oxidative stress via the adenosine monophosphate activated protein kinase/mammalian target of rapamycin signalling pathway.

CONCLUSION

Taken together, these results showed that ECE can improve exercise performance and reduce physical fatigue in mice, which indicates that ECE can be used as a potential supplement to reduce physical fatigue. © 2020 Society of Chemical Industry.

Apolipoprotein E Polymorphism and Frailty: Apolipoprotein ε4 Allele Is Associated with Fatigue but Not Frailty Syndrome in a Community-Dwelling Older Population Cohort

OBJECTIVE

Frailty is known to be influenced by genetics, however, little evidence on the association of Apolipoprotein E (ApoE) genotype and frailty exists which we aim to investigate.

DESIGN

This study is a cross-sectional analysis from a prospective longitudinal study cohort.

SETTING AND PARTICIPANTS

Community-dwelling individuals aged 55 years and older from Beijing region in China.

MEASUREMENTS

A total of 3,569 older adults with a mean age of 75.06(±6.79) years were included. We investigated the association between ApoE polymorphism and frailty syndrome using the frailty index (FI) and frailty phenotype (including association with individual components of the frailty phenotype). Logistic regressions were performed to investigate the relation between ApoE variants and frailty.

RESULTS

There was no significant association between ApoE variants and frailty as assessed by the FI. In the age and sex-adjusted model, compared to the ApoE e3/e3 carriers ApoE e4 carriers had almost 1.5 times higher odds of being frail as assessed by the frailty phenotype. However, the significance was lost on the model with adjustment for cognitive impairment. Compared to the ApoE e3/e3 carriers ApoE e4 carriers had almost two times higher odds of fatigue. ApoE e4 heterozygotes had higher odds of fatigue compared to ApoE e4 non-carriers. No significant association was found between ApoE variants and other components of frailty phenotype.

CONCLUSIONS

Our findings do not support an association between ApoE genotype and frailty irrespective of the frailty assessment tools. Fatigue in older adults is the only component of frailty phenotype influenced by ApoE genotype.

Epidemiology of Perceived Physical Fatigability in Older Adults: The Long Life Family Study

BACKGROUND

Fatigability is a construct that measures whole-body tiredness anchored to activities of a fixed intensity and duration; little is known about its epidemiology and heritability.

METHODS

Two generations of family members enriched for exceptional longevity and their spouses were enrolled (2006-2009) in the Long Life Family Study (LLFS). At Visit 2 (2014-2017, N = 2,355) perceived physical fatigability was measured using the 10-item self-administered Pittsburgh Fatigability Scale (PFS), along with demographic, medical, behavioral, physical, and cognitive risk factors.

RESULTS

Residual genetic heritability of fatigability was 0.263 (p = 6.6 × 10-9) after adjustment for age, sex, and field center. PFS physical scores (mean ± SD) and higher physical fatigability prevalence (% PFS ≥ 15) were greater with each age strata: 60-69 (n = 1,009, 11.0 ± 7.6, 28%), 70-79 (n = 847, 12.5 ± 8.1, 37%), 80-89 (n = 253, 19.3 ± 9.9, 65.2%), and 90-108 (n = 266, 28.6 ± 9.8, 89.5%), p < .0001, adjusted for sex, field center, and family relatedness. Women had a higher prevalence of perceived physical fatigability compared to men, with the largest difference in the 80-89 age strata, 74.8% versus 53.5%, p < .0001. Those with greater body mass index, worse physical and cognitive function, and lower physical activity had significantly higher perceived physical fatigability.

CONCLUSIONS

Perceived physical fatigability is highly prevalent in older adults and strongly associated with age. The family design of LLFS allowed us to estimate the genetic heritability of perceived physical fatigability. Identifying risk factors associated with higher perceived physical fatigability can inform the development of targeted interventions for those most at risk, including older women, older adults with depression, and those who are less physically active.

A randomized placebo-controlled trial of bupropion for Cancer-related fatigue: Study design and procedures

BACKGROUND

Cancer-related fatigue is a significant problem and is associated with poor quality of life. Behavioral interventions include exercise and cognitive-behavioral therapy, which survivors may be unwilling or unable to adopt. Pharmacologic interventions (e.g., selective serotonin reuptake inhibitors) have been disappointing. One potential therapy is the antidepressant bupropion, a norepinephrine-dopamine reuptake inhibitor that targets both inflammation and the hypothalamic-pituitary-adrenal axis. The current study is intended to provide a rigorous test of the efficacy and tolerability of bupropion for cancer-related fatigue.

METHODS

A randomized, double-blind, placebo-controlled trial will examine the effects of bupropion on cancer-related fatigue. The trial will be conducted nationwide through the University of Rochester Medical Center (URMC) National Cancer Institute Community Oncology Research Program (NCORP). Disease-free breast cancer survivors (n = 422) who completed chemotherapy and/or radiotherapy 12-60 months previously and report significant fatigue will be randomized 1:1 to receive bupropion (300 mg/day) or placebo. Outcomes will be assessed at baseline and the 12-week follow-up. The primary outcome, fatigue, will be measured with the Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT-F). Secondary outcomes include quality of life, depression, and drug tolerability. Exploratory outcomes include cognition and symptomatology. Potential biological mechanisms and genetic moderators of cancer-related fatigue will also be explored.

DISCUSSION

This study is the first placebo-controlled trial to our knowledge to evaluate bupropion for cancer-related fatigue. Positive results could revolutionize the treatment of cancer-related fatigue, as bupropion is safe, inexpensive, widely-available, and may be more tolerable and acceptable for many patients than current, limited treatment options.

Activation of Transposable Elements in Immune Cells of Fibromyalgia Patients

Advancements in nucleic acid sequencing technology combined with an unprecedented availability of metadata have revealed that 45% of the human genome constituted by transposable elements (TEs) is not only transcriptionally active but also physiologically necessary. Dysregulation of TEs, including human retroviral endogenous sequences (HERVs) has been shown to associate with several neurologic and autoimmune diseases, including Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). However, no study has yet addressed whether abnormal expression of these sequences correlates with fibromyalgia (FM), a disease frequently comorbid with ME/CFS. The work presented here shows, for the first time, that, in fact, HERVs of the H, K and W types are overexpressed in immune cells of FM patients with or without comorbid ME/CFS. Patients with increased HERV expression (N = 14) presented increased levels of interferon (INF-β and INF-γ) but unchanged levels of TNF-α. The findings reported in this study could explain the flu-like symptoms FM patients present with in clinical practice, in the absence of concomitant infections. Future work aimed at identifying specific genomic loci differentially affected in FM and/or ME/CFS is warranted.

Symptom Science: Advocating for Inclusion of Functional Genetic Polymorphisms

Incorporating biologically based data into symptom science research can contribute substantially to understanding commonly experienced symptoms across chronic conditions. The purpose of this literature review was to identify functional polymorphisms associated with common symptoms (i.e., pain, sleep disturbance, fatigue, affective and cognitive symptoms) with the goal of identifying a parsimonious list of functional genetic polymorphisms with evidence to advocate for their inclusion in symptom science research. PubMed was searched to identify genes and functional polymorphisms associated with symptoms across chronic conditions, revealing eight functional genetic polymorphisms in seven different genes that showed evidence of association with at least three or more symptoms and/or symptom clusters: BDNF rs6265, COMT rs4680, FKBP5 rs3800373, IL-6 rs1800795, NFKB2 rs1056890, SLC6A4 5-HTTLPR+rs25531, and TNFA rs1799964 and rs1800629. Of these genes, three represent protein biomarkers previously identified as common data elements for symptom science research (BDNF, IL-6, and TNFA), and the polymorphisms in these genes identified through the search are known to impact secretion or level of transcription of these protein biomarkers. Inclusion of genotype data for polymorphisms offers great potential to further advance scientific knowledge of the biological basis of individual symptoms and symptom clusters across studies. Additionally, these polymorphisms have the potential to be used as targets to optimize precision health through the identification of individuals at risk for poor symptom experiences as well as the development of symptom management interventions.

Whole blood human transcriptome and virome analysis of ME/CFS patients experiencing post-exertional malaise following cardiopulmonary exercise testing

Myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) is a syndrome of unknown etiology characterized by profound fatigue exacerbated by physical activity, also known as post-exertional malaise (PEM). Previously, we did not detect evidence of immune dysregulation or virus reactivation outside of PEM periods. Here we sought to determine whether cardiopulmonary exercise stress testing of ME/CFS patients could trigger such changes. ME/CFS patients (n = 14) and matched sedentary controls (n = 11) were subjected to cardiopulmonary exercise on 2 consecutive days and followed up to 7 days post-exercise, and longitudinal whole blood samples analyzed by RNA-seq. Although ME/CFS patients showed significant worsening of symptoms following exercise versus controls, with 8 of 14 ME/CFS patients showing reduced oxygen consumption ([Formula: see text]) on day 2, transcriptome analysis yielded only 6 differentially expressed gene (DEG) candidates when comparing ME/CFS patients to controls across all time points. None of the DEGs were related to immune signaling, and no DEGs were found in ME/CFS patients before and after exercise. Virome composition (P = 0.746 by chi-square test) and number of viral reads (P = 0.098 by paired t-test) were not significantly associated with PEM. These observations do not support transcriptionally-mediated immune cell dysregulation or viral reactivation in ME/CFS patients during symptomatic PEM episodes.

A Pilot Study Using a Multistaged Integrated Analysis of Gene Expression and Methylation to Evaluate Mechanisms for Evening Fatigue in Women Who Received Chemotherapy for Breast Cancer

CONTEXT

Fatigue is the most common symptom associated with cancer and its treatment. Investigation of molecular mechanisms associated with fatigue may identify new therapeutic targets.

OBJECTIVE

The objective of this pilot study was to evaluate the relationships between gene expression and methylation status and evening fatigue severity in women with breast cancer who received chemotherapy.

METHODS

Latent class analysis (LCA) was used to identify evening fatigue phenotypes. In this analysis, the lowest (i.e., moderate, n = 7) and highest (i.e., very high, n = 29) fatigue-severity classes identified using LCA were analyzed via two stages. First, a total of 32,609 transcripts from whole blood were evaluated for differences in expression levels between the classes. Next, 637 methylation sites located within the putative transcription factor binding sites for those genes demonstrating differential expression were evaluated for differential methylation state between the classes.

RESULTS

A total of 89 transcripts in 75 unique genes were differentially expressed between the moderate (the lowest fatigue-severity class identified) and very high evening fatigue classes. In addition, 23 differentially methylated probes and three differentially methylated regions were found between the moderate and very high evening fatigue classes.

CONCLUSIONS

Using a multistaged integrated analysis of gene expression and methylation, differential methylation was identified in the regulatory regions of genes associated with previously hypothesized mechanisms for fatigue, including inflammation, immune function, neurotransmission, circadian rhythm, skeletal muscle energy, carbohydrate metabolism, and renal function as well as core biological processes including gene transcription and the cell-cycle regulation.

Differential regulation of NF-kB and IRF target genes as they relate to fatigue in patients with head and neck cancer

Previous studies have linked plasma inflammatory markers to elevated fatigue in patients with head and neck cancer (HNC). To identify the molecular mechanisms underlying this association, we conducted promoter-based bioinformatics analyses to determine the relationship between fatigue and specific gene expression profiles associated with inflammation in human papillomavirus (HPV)-related and -unrelated HNC patients undergoing treatment. Patients with newly diagnosed HNC without distant metastasis were assessed at baseline (pre-radiotherapy) and one-month post-radiotherapy. Fatigue was measured by the Multidimensional Fatigue Inventory. Genome-wide gene expression profiles were collected from peripheral blood mononuclear cells (PBMC). Promoter-based bioinformatics analyses were employed to identify transcription control pathways underlying transcriptomic correlates of fatigue in the sample as a whole and in HPV-related and HPV-unrelated HNC patients separately. In transcriptome profiling analyses of PBMC from 44 patients, TELiS bioinformatics analyses linked fatigue to increased nuclear factor-kappa B (NF-kB) transcriptional activity and decreased interferon regulatory factor family (IRF) transcription factor activity. Patients with HPV-related HNC showed lower levels of fatigue-related gene expression profile compared to HPV-unrelated HNC. Fatigue in HNC patients undergoing treatment is associated with gene expression profiles consistent with the conserved transcriptional response to adversity (CTRA) characterized by increased proinflammatory and decreased anti-antiviral transcriptional activity. Interestingly, this CTRA response was mitigated in patients with HPV-related HNC and may explain the lower level of fatigue they experience relative to HPV-unrelated HNC.

β-glucan Salecan Improves Exercise Performance and Displays Anti-Fatigue Effects through Regulating Energy Metabolism and Oxidative Stress in Mice

Fatigue induced by prolonged exercise not only leads to the decrease of exercise capacity, but also might be the cause of many diseases. In consideration of the side effects of pharmacological drugs, dietary supplements seem to be a better choice to ameliorate exercise-induced fatigue. The present study aimed to investigate the anti-fatigue effect of Salecan, a novel water-soluble β-glucan, during exercise and explore the underlying mechanisms. Male Institute of Cancer Research (ICR) mice were divided into five groups, including the Rest group and the other four Swim-groups treated with Salecan at 0, 25, 50, and 100 mg/kg/day for four weeks. Salecan treatment markedly increased the exhaustive swimming time of mice in the forced swimming test. Exercise fatigue and injury-related biochemical biomarkers including lactate, blood urea nitrogen (BUN), creatinine kinase (CK), alanine transaminase (ALT), and aspartate transaminase (AST) were ameliorated by Salecan. Salecan reversed the decreased serum glucose levels and glycogen contents caused by exercise. In addition, Salecan improved oxidative stress induced by exercise through regulating Nrf2/HO–1/Trx signaling pathway. Thus, the beneficial effects of Salecan against fatigue may be due to its positive effects on energy metabolism and antioxidation defence. Our results suggest that Salecan could be a novel potential candidate for anti-fatigue dietary supplements.

Genomic mechanisms of fatigue in survivors of colorectal cancer

BACKGROUND

Many cancer survivors experience fatigue as a nagging symptom lasting years after treatment. To learn of the relevant biological pathways involved in fatigue among cancer survivors, the authors tested for an association between fatigue levels and leukocyte gene expression profiles and determined the specific mediating immune cell types.

METHODS

A sample of 89 Hispanic/Latino adults aged 60.5 years, 62% of whom were male, who were diagnosed with colorectal cancer and were 2.9 years since diagnosis provided blood for transcriptome profiling and completed a validated measure of fatigue (Multidimensional Fatigue Symptom Inventory-Short Form). The authors applied genome-wide transcriptional profiling of leukocyte RNA to identify gene expression activity associated with fatigue, tested for the activity of specific transcription factors involved in previously established markers of inflammation and immunologic activation, and identified the specific cell types mediating these transcriptional alterations.

RESULTS

In analyses adjusting for demographic and behavioral health risk factors, results linked fatigue with increased activation of B lymphocytes and CD8-positive T cells, as well as several transcription factors involved in immune activation (nuclear factor κB [NF-κB], signal transducer and activator of transcription [STAT], and cAMP responsive element-binding protein [CREB]). Results also replicated several specific genomic effects previously observed in fatigued cancer survivors, including upregulated expression of α-synuclein (SNCA) and hemoglobin subunits (HBA and HBB).

CONCLUSIONS

Cancer survivors' heightened fatigue levels may be partially explained by activation of specific immune cell subsets, thereby providing a potential molecular biomarker for clinical interventions targeting the remediation of fatigue. Cancer 2018;124:2637-44. © 2018 American Cancer Society.

Susceptibility and severity of cancer-related fatigue in colorectal cancer patients is associated with SLC6A4 gene single nucleotide polymorphism rs25531 A>G genotype

PURPOSE

To explore the correlation between the SERT gene promoter single nucleotide polymorphisms (SNPs) rs25531 and rs956304 and the cancer-related fatigue (CRF) of colon and rectal cancer, and also to analyze the correlation of the interaction of genetic and non-genetic factors.

METHOD

A sample of 568 colon and rectal cancer patients were recruited from the Second Affiliated Hospital of Nanchang University from October 2013 to December 2015. The Chinese version of the Brief Fatigue Inventory (BFI-C) was used to evaluate the CRF. The genomic DNA was extracted from peripheral blood samples of the patients. Direct sequencing was used to determine the rs25531 and rs956304 genotypes.

RESULTS

Compared with the AA genotype, the risk of suffering from CRF and the severity of CRF increased to 1.77 times (95% CI = 1.22-2.59, P = 0.003) for patients who carry with G allele (AG+GG genotype) at rs25531 locus.

CONCLUSIONS

The SERT gene promoter SNP rs25531 was associated with the CRF in patients with colon and rectal cancer and the G genotype was an independent risk factor for CRF among individuals with colon and rectal cancer in the study.

Genetic contributions to self-reported tiredness

Self-reported tiredness and low energy, often called fatigue, are associated with poorer physical and mental health. Twin studies have indicated that this has a heritability between 6 and 50%. In the UK Biobank sample (N=108 976), we carried out a genome-wide association study (GWAS) of responses to the question, 'Over the last two weeks, how often have you felt tired or had little energy?' Univariate GCTA-GREML found that the proportion of variance explained by all common single-nucleotide polymorphisms for this tiredness question was 8.4% (s.e.=0.6%). GWAS identified one genome-wide significant hit (Affymetrix id 1:64178756_C_T; P=1.36 × 10-11). Linkage disequilibrium score regression and polygenic profile score analyses were used to test for shared genetic aetiology between tiredness and up to 29 physical and mental health traits from GWAS consortia. Significant genetic correlations were identified between tiredness and body mass index (BMI), C-reactive protein, high-density lipoprotein (HDL) cholesterol, forced expiratory volume, grip strength, HbA1c, longevity, obesity, self-rated health, smoking status, triglycerides, type 2 diabetes, waist-hip ratio, attention deficit hyperactivity disorder, bipolar disorder, major depressive disorder, neuroticism, schizophrenia and verbal-numerical reasoning (absolute rg effect sizes between 0.02 and 0.78). Significant associations were identified between tiredness phenotypic scores and polygenic profile scores for BMI, HDL cholesterol, low-density lipoprotein cholesterol, coronary artery disease, C-reactive protein, HbA1c, height, obesity, smoking status, triglycerides, type 2 diabetes, waist-hip ratio, childhood cognitive ability, neuroticism, bipolar disorder, major depressive disorder and schizophrenia (standardised β's had absolute values<0.03). These results suggest that tiredness is a partly heritable, heterogeneous and complex phenomenon that is phenotypically and genetically associated with affective, cognitive, personality and physiological processes.

Gene Expression, and Fatigue in Puerto Rican Men during Radiotherapy for Prostate Cancer: an Exploratory Study

OBJECTIVE

To examine the trajectory of fatigue experienced by 26 Puerto Rican (PR) men over the course of External Beam Radiation Therapy (EBRT) and to assess gene expression changes from baseline to midpoint of EBRT using microarray technology. Design/Research Approach- Prospective exploratory and comparative design study. Setting- RT facility located in San Juan, PR. Sample/Participants-26 PR men with non-metastatic prostate cancer.

METHODS

Participants completed 2 paper forms: demographics and the Spanish version of the 13-item FACT-fatigue at baseline, midpoint, and end of EBRT. Wholeblood samples were collected at baseline and at midpoint of EBRT. Descriptive data was analyzed using t-test, Wilcoxon, and Friedman test for repeated measures. Gene expression data was analyzed using the LIMMA package in R; the functional network analysis was conducted using Ingenuity Pathway analysis. Main Research Variable-Fatigue scores, gene expression.

RESULTS

Subjects were of ages 52-81 with fatigue scores that remained unchanged during EBRT (baseline=42.38, SD=9.34; midpoint=42.11, SD=8.93, endpoint=43.04, SD=8.62). Three hundred seventy-three genes (130-up regulated and 243-down regulated) were differentially expressed from baseline to mid-point of EBRT (FDR<0.01). The top distinct canonical pathways of the differentially expressed probesets (p<0.0001) were: "Phospholipase C Signaling," "Role of NFAT in Regulation of the Immune Response," and "Gαq Signaling."

CONCLUSION

While fatigue did not worsen over the course of EBRT for this sample as a group, there was variability in fatigue across the sample. It is possible that the over expression of the SESN3 gene, known to suppress oxidative damage, may have contributed to the attenuation of fatigue in this clinical population.

Interstitial microdeletion of 17q11.2 is associated with hypotonia, fatigue, intellectual disability, and a subtle facial phenotype in three unrelated patients

Over the past decade chromosomal microarray analysis (array CGH) has allowed the discovery of many novel disease-causing recurrent microdeletion and microduplication syndromes. Here we present three unrelated patients (2F; 1M) from three different countries, with developmental delay, intellectual disability, hypotonia, fatigue, and highly similar dysmorphic facial features. Shared facial features are a broad and wide forehead, similar shape of the eyes with long palpebral fissures, a bulbous tip of the nose and thick lips. Intellectual disabilities range from mild to severe. One female patient and the male patient were investigated in childhood for significant hypotonia thought to be suggestive of a neuromuscular disorder. The two female patients also show excessive fatigue with daytime somnolence. The patients carry overlapping, de novo microdeletions of chromosome 17q11.2, with sizes ranging from 0.97 to 1.18 Mb. The smallest region of overlap (SRO) between the three patients is 863 kb, and contains seven genes, five of which are predicted to exhibit haploinsufficiency (CDK5R1, PSMD11, RHOT1, SUZ12, ZNF207) although none has yet been associated with genetic syndromes. Of these five genes, the brain expressed CDK5R1 gene constitutes a good candidate for the developmental delay, while the RHOT1 gene, involved in mitochondrial trafficking, might underlie the hypotonia and the excessive fatigue.

Anti-fatigue activity of sea cucumber peptides prepared from Stichopus japonicus in an endurance swimming rat model

BACKGROUND

Sea cucumber (Stichopus japonicus) is a well-known nutritious and luxurious seafood in Asia which has attracted increasing attention because of its nutrition and bioactivities in recent years. In this study, the anti-fatigue activity of sea cucumber peptides (SCP) prepared from S. japonicus was evaluated in a load-induced endurance swimming model.

RESULTS

The SCP prepared in this study was mainly made up of low-molecular-weight peptides (<2 kDa). The analysis result of amino acid composition revealed that SCP was rich in glycine, glutamic acid and proline. The endurance capability of rats to fatigue was significantly improved by SCP treatment. Meanwhile, the remarkable alterations of energy metabolic markers, antioxidant enzymes, antioxidant capacity and oxidative stress biomarkers were normalized. Moreover, administration of SCP could modulate alterations of inflammatory cytokines and downregulate the overexpression of TRL4 and NF-κB.

CONCLUSION

SCP has anti-fatigue activity and it exerted its anti-fatigue effect probably through normalizing energy metabolism as well as alleviating oxidative damage and inflammatory responses. © 2017 Society of Chemical Industry.

Exploring Genetic Attributions Underlying Radiotherapy-Induced Fatigue in Prostate Cancer Patients

CONTEXT

Despite numerous proposed mechanisms, no definitive pathophysiology underlying radiotherapy-induced fatigue (RIF) has been established. However, the dysregulation of a set of 35 genes was recently validated to predict development of fatigue in prostate cancer patients receiving radiotherapy.

OBJECTIVES

To hypothesize novel pathways, and provide genetic targets for currently proposed pathways implicated in RIF development through analysis of the previously validated gene set.

METHODS

The gene set was analyzed for all phenotypic attributions implicated in the phenotype of fatigue. Initially, a "directed" approach was used by querying specific fatigue-related sub-phenotypes against all known phenotypic attributions of the gene set. Then, an "undirected" approach, reviewing the entirety of the literature referencing the 35 genes, was used to increase analysis sensitivity.

RESULTS

The dysregulated genes attribute to neural, immunological, mitochondrial, muscular, and metabolic pathways. In addition, certain genes suggest phenotypes not previously emphasized in the context of RIF, such as ionizing radiation sensitivity, DNA damage, and altered DNA repair frequency. Several genes also associated with prostate cancer depression, possibly emphasizing variable radiosensitivity by RIF-prone patients, which may have palliative care implications. Despite the relevant findings, many of the 35 RIF-predictive genes are poorly characterized, warranting their investigation.

CONCLUSION

The implications of herein presented RIF pathways are purely theoretical until specific end-point driven experiments are conducted in more congruent contexts. Nevertheless, the presented attributions are informative, directing future investigation to definitively elucidate RIF's pathoetiology. This study demonstrates an arguably comprehensive method of approaching known differential expression underlying a complex phenotype, to correlate feasible pathophysiology.

Ursolic acid induces mitochondrial biogenesis through the activation of AMPK and PGC-1 in C2C12 myotubes: a possible mechanism underlying its beneficial effect on exercise endurance

Mitochondrial biogenesis, which involves an increase in mitochondrial number and the overall capacity of oxidative phosphorylation, is a critical determinant of skeletal muscle function. Recent findings have shown that some natural products can enhance mitochondrial adaptation to aerobic exercise, which in turn improves exercise performance, presumably by delaying muscle fatigue. Ursolic acid (UA), a natural triterpene, is commonly found in various vegetables and fruits. In the current study, UA was shown to increase mitochondrial mass and ATP generation capacity, with a concomitant production of a low level of mitochondrial reactive oxygen species (ROS) in C2C12 myotubes. Mitochondrial ROS, in turn, activated the redox sensitive adenosine monophosphate-dependent protein kinase (AMPK)/peroxisome proliferator-activated receptor γ coactivator-1(PGC-1) pathway. The activation of AMPK/PGC-1 further increased the expression of cytochrome c oxidase (COX) and uncoupling protein 3. Animal studies showed that UA can also dose-dependently increase the endurance exercise capacity in mice, as assessed by a weight-loaded swimming test and a hanging wire test. Our findings suggest that UA may induce mitochondrial biogenesis through the activation of AMPK and PGC-1 pathways in skeletal muscle, thereby offering a promising prospect for its use to enhance exercise endurance and alleviating fatigue in humans.

A systematic review of the association between fatigue and genetic polymorphisms

Fatigue is one of the most common and distressing symptoms, leading to markedly decreased quality of life among a large subset of patients with a variety of disorders. Susceptibility to fatigue may be influenced by genetic factors including single nucleotide polymorphisms (SNPs), especially in the regulatory regions, of relevant genes. To further investigate the association of SNPs with fatigue in various patient populations, a systematic search was conducted on Pubmed, CINAHL, PsycINFO, and Sociological Abstracts Database for fatigue related-terms in combination with polymorphisms or genetic variation-related terms. Fifty papers in total met the inclusion and exclusion criteria for this analysis. These 50 papers were further classified into three subgroups for evaluation: chronic fatigue syndrome (CFS), cancer-related fatigue (CRF) and other disease-related fatigue. SNPs in regulatory pathways of immune and neurotransmitter systems were found to play important roles in the etiologies of CFS, CRF and other disease-related fatigue. Evidence for associations between elevated fatigue and specific polymorphisms in TNFα, IL1b, IL4 and IL6 genes was revealed for all three subgroups of fatigue. We also found CFS shared a series of polymorphisms in HLA, IFN-γ, 5-HT and NR3C1 genes with other disease-related fatigue, however these SNPs (excluding IFN-γ) were not found to be adequately investigated in CRF. Gaps in knowledge related to fatigue etiology and recommendations for future research are further discussed.

Associations Between Neurotransmitter Genes and Fatigue and Energy Levels in Women After Breast Cancer Surgery

CONTEXT

Fatigue is a common problem in oncology patients. Less is known about decrements in energy levels and the mechanisms that underlie both fatigue and energy.

OBJECTIVES

In patients with breast cancer, variations in neurotransmitter genes between lower and higher fatigue latent classes and between the higher and lower energy latent classes were evaluated.

METHODS

Patients completed assessments before and monthly for six months after surgery. Growth mixture modeling was used to identify distinct latent classes for fatigue severity and energy levels. Thirty candidate genes involved in various aspects of neurotransmission were evaluated.

RESULTS

Eleven single-nucleotide polymorphisms or haplotypes (i.e., ADRB2 rs1042718, BDNF rs6265, COMT rs9332377, CYP3A4 rs4646437, GALR1 rs949060, GCH1 rs3783642, NOS1 rs9658498, NOS1 rs2293052, NPY1R Haplotype A04, SLC6A2 rs17841327, and 5HTTLPR + rs25531 in SLC6A4) were associated with latent class membership for fatigue. Seven single-nucleotide polymorphisms or haplotypes (i.e., NOS1 rs471871, SLC6A1 rs2675163, SLC6A1 Haplotype D01, SLC6A2 rs36027, SLC6A3 rs37022, SLC6A4 rs2020942, and TAC1 rs2072100) were associated with latent class membership for energy. Three of 13 genes (i.e., NOS1, SLC6A2, and SLC6A4) were associated with latent class membership for both fatigue and energy.

CONCLUSIONS

Molecular findings support the hypothesis that fatigue and energy are distinct, yet related symptoms. Results suggest that a large number of neurotransmitters play a role in the development and maintenance of fatigue and energy levels in breast cancer patients.

Different Phenotyping Approaches Lead to Dissimilar Biologic Profiles in Men With Chronic Fatigue After Radiation Therapy

CONTEXT

Cancer-related fatigue (CRF) persists months after treatment completion. Although a CRF biomarker has not yet been identified, validated self-report questionnaires are used to define and phenotype CRF in the discovery of potential biomarkers.

OBJECTIVES

The purposes of this study are to identify CRF subjects using three well-known CRF phenotyping approaches using validated self-report questionnaires and to compare the biologic profiles that are associated with each CRF phenotype.

METHODS

Fatigue in men with nonmetastatic prostate cancer receiving external beam radiation therapy was measured at baseline (T1), midpoint (T2), end point (T3), and one-year post-external beam radiation therapy (T4) using the Functional Assessment of Cancer Therapy-Fatigue (FACT-F) and Patient Reported Outcomes Measurement Information System-Fatigue. Chronic fatigue (CF) and nonfatigue subjects were grouped based on three commonly used phenotyping approaches: 1) T4 FACT-F <43; 2) T1-T4 decline in FACT-F score ≥3 points; 3) T4 Patient Reported Outcomes Measurement Information System-Fatigue T-score >50. Differential gene expressions using whole-genome microarray analysis were compared in each of the phenotyping criterion.

RESULTS

The study enrolled 43 men, where 34%-38% had CF based on the three phenotyping approaches. Distinct gene expression patterns were observed between CF and nonfatigue subjects in each of the three CRF phenotyping approaches: 1) Approach 1 had the largest number of differentially expressed genes and 2) Approaches 2 and 3 had 40 and 21 differentially expressed genes between the fatigue groups, respectively.

CONCLUSION

The variation in genetic profiles for CRF suggests that phenotypic profiling for CRF should be carefully considered because it directly influences biomarker discovery investigations.

Polymorphisms in Cytokine Genes Are Associated With Higher Levels of Fatigue and Lower Levels of Energy in Women After Breast Cancer Surgery

CONTEXT

Little is known about the phenotypic and molecular characteristics associated with changes over time in fatigue and lack of energy in patients with breast cancer.

OBJECTIVES

The aim of this study was to identify subgroups (i.e., latent classes) of women with distinct fatigue and energy trajectories; evaluate for differences in phenotypic characteristics between the latent classes for fatigue and energy; and evaluate for associations between polymorphisms in genes for pro- and anti-inflammatory cytokines, their receptors, and their transcriptional regulators and latent class membership.

METHODS

Patients were enrolled before and followed for six months after breast cancer surgery. Latent class analyses were done to identify subgroups of patients with distinct fatigue and energy trajectories. Candidate gene analyses were done to identify cytokine genes associated with these two symptoms.

RESULTS

For both fatigue and lack of energy, two distinct latent classes were identified. Phenotypic characteristics associated with the higher fatigue class were younger age, higher education, lower Karnofsky Performance Status score, higher comorbidity, higher number of lymph nodes removed, and receipt of chemotherapy (CTX). Polymorphisms in interleukin (IL) 1β and IL10 were associated with membership in the higher fatigue class. Phenotypic characteristics associated with the lower energy class included: a lower Karnofsky Performance Status score and a higher comorbidity score. A polymorphism in IL1R1 was associated with membership in the lower energy class.

CONCLUSION

Within each latent class, the severity of fatigue and decrements in energy were relatively stable over the first six months after breast cancer surgery. Distinct phenotypic characteristics and genetic polymorphisms were associated with membership in the higher fatigue and lower energy classes.

Genomic Variants Associated With Cancer-Related Fatigue: A Systematic Review

BACKGROUND

Cancer-related fatigue (CRF) is the most common stressful side effect caused by cancer and cancer treatments. Although CRF causes a significant burden to quality of life, no pharmacologic interventions are available because the mechanism remains unknown.

OBJECTIVES

This systematic review analyzed the genomic variants that have been found to be associated with CRF.

METHODS

A search for peer-reviewed articles through PubMed, EBSCOhost, and DePaul WorldCat Libraries Worldwide yielded 16 published studies.

FINDINGS

The majority of genomic variants demonstrated that the inflammatory and immune response pathways, including the neuro-proinflammatory cytokine pathway, have statistically significant associations with CRF. Additional genomic studies are still needed to validate the findings in this systematic review. The exact biologic underpinnings that contribute to the development of CRF remain unknown.

Cytokine mRNA expression in patients with multiple sclerosis and fatigue

Background: Fatigue is one of the most common disabling symptoms in patients with multiple sclerosis (MS), but the putative role of proinflammatory cytokines remains to be elucidated. Methods: Thirty-seven patients (27 women, 10 men) with relapsing-remitting (n =29) and secondary progressive (n =8) MS, aged 41.0 ± 10.2 years, were studied. Fatigue was assessed by Krupp’s Fatigue Severity Scale (FSS). C ytokine mRNA expression for interferon (IFN)-g, tumor necro sis factor (TNF)-a and interleukin (IL)-10 were measured by real time RT PC R. A utonomic function was evaluated by standard tests for parasympathetic and sympathetic function, as well as by serum levels of norepinephrine and epinephrine. Results: Median levels of TNF-a mRNA expression were significantly higher in MS patients with (FSS]-4.0 and]-5.0, n=26 and n=14, respectively) than in those without fatigue (FSSB-4.0, n =11). No differences were seen for IFN-g and IL-10 mRNA expression. C ytokine levels were not correlated to autonomic tests or to serum catecho lamine levels. Conclusions: These results suggest that TNF-a, as a principal proinflammatory mediator, is associated with MS-related fatigue. This is in support of a patho genic role of the MS-related inflammatory process in the development of fatigue.

A Transcriptional Signature of Fatigue Derived from Patients with Primary Sjögren's Syndrome

Background

Fatigue is a debilitating condition with a significant impact on patients’ quality of life. Fatigue is frequently reported by patients suffering from primary Sjögren’s Syndrome (pSS), a chronic autoimmune condition characterised by dryness of the eyes and the mouth. However, although fatigue is common in pSS, it does not manifest in all sufferers, providing an excellent model with which to explore the potential underpinning biological mechanisms.

Methods

Whole blood samples from 133 fully-phenotyped pSS patients stratified for the presence of fatigue, collected by the UK primary Sjögren’s Syndrome Registry, were used for whole genome microarray. The resulting data were analysed both on a gene by gene basis and using pre-defined groups of genes. Finally, gene set enrichment analysis (GSEA) was used as a feature selection technique for input into a support vector machine (SVM) classifier. Classification was assessed using area under curve (AUC) of receiver operator characteristic and standard error of Wilcoxon statistic, SE(W).

Results

Although no genes were individually found to be associated with fatigue, 19 metabolic pathways were enriched in the high fatigue patient group using GSEA. Analysis revealed that these enrichments arose from the presence of a subset of 55 genes. A radial kernel SVM classifier with this subset of genes as input displayed significantly improved performance over classifiers using all pathway genes as input. The classifiers had AUCs of 0.866 (SE(W) 0.002) and 0.525 (SE(W) 0.006), respectively.

Conclusions

Systematic analysis of gene expression data from pSS patients discordant for fatigue identified 55 genes which are predictive of fatigue level using SVM classification. This list represents the first step in understanding the underlying pathophysiological mechanisms of fatigue in patients with pSS.

The Association between Chronic Widespread Musculoskeletal Pain, Depression and Fatigue Is Genetically Mediated

BACKGROUND

Chronic widespread muscoloskeletal pain (CWP) is prevalent in the general population and associated with high health care costs, so understanding the risk factors for chronic pain is important for both those affected and for society. In the present study we investigated the underlying etiological structure of CWP to understand better the association between the major clinical features of fatigue, depression and dihydroepiandrosterone sulphate (DHEAS) using a multivariate twin design.

METHODOLOGY/PRINCIPLE FINDINGS

Data were available in 463 UK female twin pairs including CWP status and information on depression, chronic fatigue and serum DHEAS levels. High to moderate heritabilities for all phenotypes were obtained (42.58% to 74.24%). The highest phenotypic correlation was observed between fatigue and CWP (r = 0.45), and the highest genetic correlation between CWP and fatigue (rg = 0.78). Structural equation modeling revealed the AE Cholesky model to provide the best model of the observed data. In this model, two additive genetic factors could be detected loading heavily on CWP-A2 explaining 40% of the variance and A3 20%. The factor loading heaviest on DHEAS showed only a small loading on the other phenotypes and none on fatigue at all. Furthermore, one distinct non-shared environmental factor loading specifically on CWP-but not on any of the other phenotypes-could be detected suggesting that the association between CWP and the other phenotypes is due only to genetic factors.

CONCLUSIONS/SIGNIFICANCE

Our results suggest that CWP and its associated features share a genetic predisposition but that they are relatively distinct in their environmental determinants.

Phenotypic and Molecular Evidence Suggests That Decrements in Morning and Evening Energy Are Distinct but Related Symptoms

CONTEXT

Little is known about energy levels in oncology patients and their family caregivers.

OBJECTIVES

This study sought to identify latent classes of participants, based on self-reported energy levels and evaluate for differences in phenotypic and genotypic characteristics between these classes.

METHODS

Energy subscale scores from the Lee Fatigue Scale were used to determine latent class membership. Morning and evening energy scores were obtained just before, during, and for four months after the completion of radiation therapy. Genetic associations were evaluated for 15 proinflammatory and anti-inflammatory cytokine genes.

RESULTS

Two latent classes with distinct morning energy trajectories were identified. Participants who were younger, female, not married/partnered, black, and had more comorbidities, and a lower functional status were more likely to be in the low morning energy class. Two polymorphisms (IL2 rs1479923 and NFKB1 rs4648110) were associated with morning energy latent class membership. Two latent classes with distinct evening energy trajectories were identified. Participants who were younger and male and who had more comorbidities, decreased body weight, and a lower functional status were more likely to be in the moderate evening energy class. Five different polymorphisms (IL1R2 rs4141134, IL6 rs4719714, IL17A rs8193036, NFKB2 rs1056890, and TNFA rs1800683) were associated with evening energy latent class membership.

CONCLUSION

This study provides preliminary evidence that decrements in morning and evening energy are associated with different phenotypic risk factors and cytokine gene variations.

Impact of corticosteroid-binding globulin deficiency on pregnancy and neonatal sex

CONTEXT

Plasma corticosteroid-binding globulin (CBG) transports cortisol but high progesterone levels at the maternal-fetal interface can displace cortisol from its steroid-binding site. A secretion-deficient CBG mutant (A51V) in ∼1 of 36 Chinese causes low circulating CBG levels.

OBJECTIVE

Assess the implications of a CBG deficiency on pregnancy outcomes.

PARTICIPANTS AND DESIGN

From 1978 Chinese women screened at 12-16 weeks' gestation, 50 A51V carriers were identified and 46 were followed with 60 controls throughout pregnancy. Blood samples from another 2051 pregnant women were obtained at term to determine the secondary sex ratio (SSR) of newborns in an extended cohort (n = 101) of A51V mothers.

OUTCOME MEASURES AND RESULTS

Among women recruited at 12-16 weeks' gestation, serum CBG increased progressively during pregnancy but was lower (P < .0001) in heterozygous A51V carriers than controls. Two women homozygous for A51V had very low serum CBG but their pregnancies progressed normally. The A51V mothers did not differ from controls in body mass index, gestational age at delivery, duration of parturition, blood pressure, gravidity, infant birth weight and size, or placental weights, and reported no unusual clinical symptoms. Peripheral CBG and progesterone levels correlated (r = 0.459) during first and second trimesters. Progesterone levels were much higher in intervillous blood and correlated (r = 0.637) with CBG levels. A female-skewed SSR in newborns of A51V mothers (0.77) differed (P < .05) from the SSR (1.17) in a reference cohort.

CONCLUSIONS

CBG influences progesterone levels in peripheral blood and at the maternal-fetal interface. The female-skewed SSR suggests that male fetal survival is compromised in CBG-deficient mothers.

Sex hormone binding globulin deficiency due to a homozygous missense mutation

CONTEXT

SHBG is known as the major sex steroid binding protein in plasma, and it regulates the bioavailability of both T and estradiol levels required for effects on target tissues. We identified a man with an undetectable SHBG concentration in combination with low total T. He presented with a 7-year history of muscle weakness, fatigue, and a low libido.

OBJECTIVES

To determine the cause of the SHBG deficiency, we employed both genetic analysis of the SHBG gene and transgene SHBG expression.

RESULTS

Genetic analysis identified a novel homozygous missense mutation that was predicted to be deleterious for protein function. Transgene expression showed that the mutation resulted in a block in SHBG secretion accompanied by increased expression of the endoplasmic reticulum molecular chaperone HSPA5. The mutation results in accumulation of the mutant SHBG within the cell and failure to secrete the mutant protein. Screening of family members identified one sister who was also deficient for SHBG.

CONCLUSIONS

We have identified a family with a missense mutation within the SHBG gene, which results in a complete deficiency of plasma SHBG in the homozygous state. Although total T level was low in the male patient, it did not interfere with normal gonadal development and spermatogenesis, suggesting a limited role of SHBG in sexual maturation and male physiology.

[Involvement of beta-adrenoceptors in cardioprotective effect of electroacupuncture intervention in mice with swimming fatigue-induced myocardial ischemia]

OBJECTIVE

To observe the cardioprotective effect of electroacupuncture (EA) stimulation at "Neiguan" (PC 6) in mice with myocardial ischemia (MI) and to explore the involvement of cardiac beta-adrenergic receptors (beta-AR) in the cardioprotective effect of EA intervention.

METHODS

Adult male C 57 BL/6 mice of wild type and beta1/beta2-AR double-knockout (beta1/beta2-AR(-/-)) mice were randomly and respectively divided into control group and EA group, with 8 mice in each group. These mice were subject to procedures of basic control, fatigue swimming and fatigue swimming + EA. The model was established by fatigue swimming for inducing acute MI. EA (2 Hz, 0.5 mA) was applied to bilateral "Neiguan" (PC 6) for 30 min, once daily for 7 days in both EA groups. The ST-segment of electrocardiogram (ECG) of standard limb lead II, heart rate were recorded by using a biophysical amplifier and the arrhythmia score was assessed according to Curtis and Walker's methods (1988).

RESULTS

Self-comparison showed that, compared with the baseline, the amplitude of ECG-ST II segment was obviously increased in swimming fatigue C 57 BL/6 mice (P < 0.01) and further obviously increased in beta1/beta2-AR(-/-) mice (P < 0.01), suggesting an acute MI in C 57 BL/6 mice and a worsened MI in beta1/beta2-AR(-/-) mice. Simultaneously, the heart rate was markedly decreased (P < 0.05), and the score of arrhythmia obviously increased in both C 57 BL/6 and beta1/beta2-AR(-/-) mice (P < 0.05). Compared with the modeling procedures, ECG-ST II amplitude and arrhythmia score were significantly decreased in C 57 BL/6 mice of the EA group (P < 0.01, P < 0.05), rather than in the beta1/beta2-AR(-/-) mice of the EA group (P > 0.05). In addition, heart rate levels of both C 57 BL/6 mice and beta1/beta2-AR(-/-) mice had no significant differences between control and EA groups (P > 0.05).

CONCLUSION

EA at "Neiguan" (PC 6) can protect the heart from swimming fatigue-induced MI in C 57 BL/6 mice not in beta1/beta2-AR(-/-) mice, suggesting an involvement of beta1/beta2-AR in the protective effect of EA.

A lifetime of hypercalcemia and hypercalciuria, finally explained

CONTEXT

Hypercalcemia, hypercalciuria, and recurrent nephrolithiasis are all common clinical problems. This case report illustrates a newly described but possibly not uncommon cause of this presenting complex.

OBJECTIVE

We report on a patient studied for over 30 years, with the diagnosis finally made with modern biochemical and genetic tools.

DESIGN AND SETTING

This study consists of a case report and review of literature conducted in a University Referral Center.

PATIENT AND INTERVENTION

A single patient with hypercalcemia, hypercalciuria, and recurrent nephrolithiasis was treated with low-calcium diet, low vitamin D intake, prednisone, and ketoconazole.

MAIN OUTCOME MEASURE

We measured the patient's clinical and biochemical response to interventions above.

RESULTS

Calcium absorption measured by dual isotope absorptiometry was elevated at 37.4%. Serum levels of 24,25-dihydroxyvitamin D were very low, as measured in two laboratories (0.62 ng/mL [normal, 3.49 ± 1.57], and 0.18 mg/mL). Genetic analysis of CYP24A1 revealed homozygous mutation E143del previously described. The patient's serum calcium and renal function improved markedly on treatment with ketoconazole but not with prednisone.

CONCLUSIONS

Chronic hypercalcemia, hypercalciuria, and/or nephrolithiasis may be caused by mutations in CYP24A1 causing failure to metabolize 1,25-dihydroxyvitamin D.

Chronic fatigue and personality: a twin study of causal pathways and shared liabilities

BACKGROUND

The etiology of chronic fatigue syndrome (CFS) remains unknown. Personality traits influence well-being and may play a role in CFS and unexplained chronic fatigue.

PURPOSE

This study aimed to examine the association of emotional instability and extraversion with chronic fatigue and CFS in a genetically informative sample.

METHODS

We evaluated 245 twin pairs for two definitions of chronic fatigue. They completed the Neuroticism and Extraversion subscales of the NEO Five Factor Inventory. Using a co-twin control design, we examined the association between personality and chronic fatigue.

RESULTS

Higher emotional instability was associated with both definitions of chronic fatigue and was confounded by shared genetics. Lower extraversion was also associated with both definitions of fatigue, but was not confounded by familial factors.

CONCLUSIONS

Both emotional instability and extraversion are related to chronic fatigue and CFS. Whereas emotional instability and chronic fatigue are linked by shared genetic mechanisms, the relationship with extraversion may be causal and bidirectional.

Aiming for a better understanding and management of cancer-related fatigue

Cancer-related fatigue (CRF) is a serious symptom of patients with cancer and deteriorates their daily quality of life. Whereas fatigue is a common problem in the general population, with a prevalence of about 30%, up to 99% of patients with cancer have fatigue of more intense severity. CRF is directly related to the biology of cancer, but it can also be caused by anticancer treatment. We reviewed current evidence about the potential pathophysiological mechanisms causing CRF. Clinical methods to determine the presence and severity of CRF and potential treatment options to reduce CRF will be discussed. After reading this review, the reader will have knowledge of the current understanding of CRF and will be able to give evidence-based advice to patients with CRF.

Genetic variations in interleukin-8 and interleukin-10 are associated with pain, depressed mood, and fatigue in lung cancer patients

CONTEXT

A report by the National Cancer Institute identified that an important gap in symptom research is the investigation of multiple symptoms of cancer that might identify common biological mechanisms among cancer-related symptoms.

OBJECTIVES

We applied novel statistical methods to assess whether variants of 37 inflammation genes may serve as biologic markers of risk for severe pain, depressed mood, and fatigue in non-Hispanic white patients with non-small cell lung cancer.

METHODS

Pain, fatigue, and depressed mood were assessed before cancer treatment. We used a generalized, multivariate, classification tree approach to explore the influence of single-nucleotide polymorphisms in the inflammation genes in pain, depressed mood, and fatigue in lung cancer patients.

RESULTS

Among patients with advanced-stage disease, interleukin (IL)-8-T251A was the most relevant genetic factor for pain (odds ratio [OR] = 2.18, 95% CI = 1.34-3.55, P = 0.001), depressed mood (OR = 0.37, 95% CI = 0.14-1.0), and fatigue (OR = 2.07, 95% CI = 1.16-3.70). Among those with early-stage non-small cell lung cancer, variants in the IL-10 receptor were relevant for fatigue among women. Specifically, women with Lys_Glu or Glu_Glu genotype in the IL-10 gene had a 0.49 times lower risk of severe fatigue compared with those with Lys_Lys genotype (OR = 0.49, 95% CI = 0.25-0.92, P = 0.027). Among men with early-stage lung cancer, a marginal significance was observed for IL-1A C-889T, C/T, or T/T genotypes. These men had a lower risk of severe fatigue compared with those with C/C genotype (OR = 0.38, 95% CI = 0.13-1.06).

CONCLUSION

The interaction of multiple inflammation genes, along with nongenetic factors, underlies the occurrence of symptoms. IL-8 and IL-10 may serve as potential targets for treating multiple symptoms of cancer.

Fatigue and exercise intolerance in mitochondrial diseases. Literature revision and experience of the Italian Network of mitochondrial diseases

Fatigue and exercise intolerance are common symptoms of mitochondrial diseases, but difficult to be clinically assessed. New methods to quantify these rather common complaints are strongly needed in the clinical practice. Coenzyme Q10 administration and aerobic exercise may improve exercise intolerance, but more definite studies are still pending. Herein, we have revised "how to measure" and "how to treat" these symptoms of mitochondrial patients. Subsequently, we reviewed the clinical data of the 1164 confirmed mitochondrial patients present in the Italian nation-wide database of mitochondrial disease, with special regard to exercise intolerance. We observed that more of 20% of mitochondrial patients complain of exercise intolerance. This symptom seems to be frequently associated with specific patient groups and/or genotypes. Ragged red fibers and COX-negative fibers are more often present in subjects with exercise intolerance, whereas lactate levels could not predict this symptom. Multicenter efforts are strongly needed for rare disorders such as mitochondrial diseases, and may represent the basis for more rigorous longitudinal studies.

Fatigue and fatigue-related symptoms in patients treated for different causes of hypothyroidism

OBJECTIVE

Research on determinants of well-being in patients on thyroid hormone replacement therapy is warranted, as persistent fatigue-related complaints are common in this population. In this study, we evaluated the impact of different states of hypothyroidism on fatigue and fatigue-related symptoms. Furthermore, the relationship between fatigue and the TSH receptor (TSHR)-Asp727Glu polymorphism, a common genetic variant of the TSHR, was analyzed.

DESIGN

A cross-sectional study was performed in 278 patients (140 patients treated for differentiated thyroid carcinoma (DTC) and 138 with autoimmune hypothyroidism (AIH)) genotyped for the TSHR-Asp727Glu polymorphism.

METHODS

The multidimensional fatigue inventory (MFI-20) was used to assess fatigue, with higher MFI-20 scores indicating more fatigue-related complaints. MFI-20 scores were related to disease status and Asp727Glu polymorphism status.

RESULTS

AIH patients scored significantly higher than DTC patients on all five MFI-20 subscales (P<0.001), independent of clinical and thyroid hormone parameters. The frequency of the TSHR-Glu727 allele was 7.2%. Heterozygous DTC patients had more favorable MFI-20 scores than wild-type DTC patients on four of five subscales. The modest effect of the TSHR-Asp727Glu polymorphism on fatigue was found in DTC patients only.

CONCLUSIONS

AIH patients had significantly higher levels of fatigue compared with DTC patients, which could not be attributed to clinical or thyroid hormone parameters. The modest effect of the TSHR-Asp727Glu polymorphism on fatigue in DTC patients should be confirmed in other cohorts.

Polymorphisms of the drug transporter gene ABCB1 predict side effects of treatment with cabergoline in patients with PRL adenomas

INTRODUCTION

Treatment with dopamine agonists in patients with prolactin (PRL) adenomas and Parkinson's disease is associated with central side effects. Central side effects may depend on a substance's ability to pass the blood-brain barrier, which can be actively controlled by transporter molecules such as the P-glycoprotein (P-gp) encoded by the ABCB1 gene.

MATERIALS AND METHODS

We aimed to determine whether cabergoline is transported by the P-gp and whether polymorphisms of its encoding ABCB1 gene predict central side effects of cabergoline therapy in patients with PRL adenomas. i) In an experimental mouse model lacking the homologues of the human ABCB1 gene (Abcb1ab double knockout mouse model), we examined whether cabergoline is a substrate of the P-gp using eight mutant and eight wild-type mice. ii) In a human case-control study including 79 patients with PRL adenomas treated with cabergoline at the Max Planck Institute of Psychiatry in Munich, we investigated the association of four selected ABCB1 gene single nucleotide polymorphisms (SNPs) (rs1045642, rs2032582, rs2032583 and rs2235015), with the occurrence of central side effects under cabergoline therapy.

RESULTS

i) In the experimental mouse model, we observed that brain concentrations of cabergoline were tenfold higher in the mutant mice compared with their wild-type littermates, implying that cabergoline is indeed a substrate of the transporter P-gp at the blood-brain barrier level. ii) In the human study, we observed significant negative associations under cabergoline for the C-carriers and heterozygous CT individuals of SNP rs1045642 with two central side effects (frequency of fatigue and sleep disorders) and for the G-carriers of SNP rs2032582 with the enhancement of dizziness. For the SNPs rs2235015 and rs2032583, no associations with central side effects under cabergoline were found.

DISCUSSION

This is the first study demonstrating that individual ABCB1 gene polymorphisms, reflecting a different expression and function of the P-gp, could predict the occurrence of central side effects under cabergoline. Our findings can be viewed as a step into personalised therapy in PRL adenoma patients.

Molecular signatures of peripheral blood mononuclear cells during chronic interferon-α treatment: relationship with depression and fatigue

BACKGROUND

Interferon-alpha (IFN-α) treatment for infectious disease and cancer causes high rates of depression and fatigue, and has been used to investigate the impact of inflammatory cytokines on brain and behavior. However, little is known about the transcriptional impact of chronic IFN-α on immune cells in vivo and its relationship to IFN-α-induced behavioral changes.

METHOD

Genome-wide transcriptional profiling was performed on peripheral blood mononuclear cells (PBMCs) from 21 patients with chronic hepatitis C virus (HCV) either awaiting IFN-α therapy (n=10) or at 12 weeks of IFN-α treatment (n=11).

RESULTS

Significance analysis of microarray data identified 252 up-regulated and 116 down-regulated gene transcripts. Of the up-regulated genes, 2'-5'-oligoadenylate synthetase 2 (OAS2), a gene linked to chronic fatigue syndrome (CFS), was the only gene that was differentially expressed in patients with IFN-α-induced depression/fatigue, and correlated with depression and fatigue scores at 12 weeks (r=0.80, p=0.003 and r=0.70, p=0.017 respectively). Promoter-based bioinformatic analyses linked IFN-α-related transcriptional alterations to transcription factors involved in myeloid differentiation, IFN-α signaling, activator protein-1 (AP1) and cAMP responsive element binding protein/activation transcription factor (CREB/ATF) pathways, which were derived primarily from monocytes and plasmacytoid dendritic cells. IFN-α-treated patients with high depression/fatigue scores demonstrated up-regulation of genes bearing promoter motifs for transcription factors involved in myeloid differentiation, IFN-α and AP1 signaling, and reduced prevalence of motifs for CREB/ATF, which has been implicated in major depression.

CONCLUSIONS

Depression and fatigue during chronic IFN-α administration were associated with alterations in the expression (OAS2) and transcriptional control (CREB/ATF) of genes linked to behavioral disorders including CFS and major depression, further supporting an immune contribution to these diseases.

CBG Santiago: a novel CBG mutation

CONTEXT

Corticosteroid-binding globulin (CBG; SERPIN A6) gene mutations are rare; only four mutations have been described, often in association with fatigue and chronic pain, albeit with incomplete penetrance.

PATIENT

We report a kindred with a novel SERPINA6 mutation. The proband, a 9-yr-old male, had excessive postexertional fatigue, weakness, and migraine.

MAIN OUTCOME MEASURES AND RESULTS

Investigations revealed low morning and ACTH-stimulated peak cortisol levels. SERPIN A6 sequencing detected a novel exon 2 single base deletion (c.13delC) leading to a frameshift generating a stop codon within the signal peptide coding region (p.Leu5CysfsX26) and 50% reduced CBG levels in heterozygotes. The patient's father and two sisters share the mutation. Symptom expression within the family may have been modified by a polymorphic CBG allele (c.735G>T). Exogenous hydrocortisone had no effect on the fatigue.

CONCLUSION

This report documents the fifth CBG gene mutation in humans and the second causing major effects on CBG levels. Individuals with low CBG levels may be misdiagnosed as having secondary hypocortisolism. The association with fatigue and idiopathic pain is again noted and may relate to altered stress system function. Variability of the phenotype may relate to other genetic variations of the CBG gene or environmental factors.

Fatigue and gene expression in human leukocytes: increased NF-κB and decreased glucocorticoid signaling in breast cancer survivors with persistent fatigue

Fatigue is highly prevalent in the general population and is one of the most common side effects of cancer treatment. There is growing evidence that pro-inflammatory cytokines play a role in cancer-related fatigue, although the molecular mechanisms for chronic inflammation and fatigue have not been determined. The current study utilized genome-wide expression microarrays to identify differences in gene expression and associated alterations in transcriptional activity in leukocytes from breast cancer survivors with persistent fatigue (n=11) and non-fatigued controls (n=10). We focused on transcription of inflammation-related genes, particularly those responsive to the pro-inflammatory NF-κB transcription control pathway. Further, given the role of glucocorticoids as key regulators of inflammatory processes, we examined transcription of glucocorticoid-responsive genes indicative of potential glucocorticoid receptor (GR) desensitization. Plasma levels of cortisol were also assessed. Consistent with hypotheses, results showed increased expression of transcripts with response elements for NF-κB, and reduced expression of transcripts with response elements for glucocorticoids (p<.05) in fatigued breast cancer survivors. No differences in plasma levels of cortisol were observed. These data indicate that increased activity of pro-inflammatory transcription factors may contribute to persistent cancer-related fatigue and provide insight into potential mechanisms for tonic increases in NF-κB activity, specifically decreased expression of GR anti-inflammatory transcription factors.