Category: Endocrine System

Chronic fatigue syndrome: circadian rhythm and hypothalamic-pituitary-adrenal (HPA) axis impairment

Abstract:

Chronic Fatigue Syndrome (CFS) is a clinical condition characterized by a persistent or relapsing debilitating fatigue at rest, lasting more than 6 months, and made worse by exercise. At the present moment, there are three potential etiopathogenic factors: immunologic, viral and neuroendocrine. The purpose of our study was to evaluate possible alterations of the hypothalamic-pituitary-adrenal (HPA) axis in our CFS patients by studying the circadian rhythms of prolactin (PRL), thyrotropic hormone (TSH), adrenocorticotropic hormone (ACTH), and cortisol (CS).

A total of 36 patients were enrolled according to the Centers for Disease Control and Prevention case-definition criteria. Twenty healthy subjects were included as controls. Blood samples were taken every 4 hours during a single 24-hour period. We performed a fluorometric enzyme immunoassay with serum PRL, cortisol and TSH, and an immunoradiometric assay with plasma ACTH.

The circadian rhythms of PRL, TSH, ACTH and CS were statistically significant in both CFS and control groups. At 24:00 and 04:00 hrs the CFS patients showed lower ACTH levels than healthy subjects (p < 0.001); the PRL levels were higher at 04.00 h in CFS patients than in healthy subjects.

 

Source: Racciatti D, Guagnano MT, Vecchiet J, De Remigis PL, Pizzigallo E, Della Vecchia R, Di Sciascio T, Merlitti D, Sensi S. Chronic fatigue syndrome: circadian rhythm and hypothalamic-pituitary-adrenal (HPA) axis impairment. Int J Immunopathol Pharmacol. 2001 Jan-Apr;14(1):11-15. http://www.ncbi.nlm.nih.gov/pubmed/12622884

 

Neuroendocrine disorder in chronic fatigue syndrome

Abstract:

Background/aim: Neuroendocrine disorders are considered a possible pathogenetic mechanism in chronic fatigue syndrome (CFS). The aim of our study was to determine the function of the hypothalamic–pituitary–adrenal axis (HPA) and thyroid function in women of reproductive age suffering from CFS.

Materials and methods: The study included 40 women suffering from CFS and 40 healthy women (15–45 years old). Serum levels of cortisol (0800 and 1800 hours), ACTH, total T4, total T3, and TSH were measured in all subjects. The Fibro Fatigue Scale was used for determination of fatigue level.

Results: Cortisol serum levels were normal in both groups. The distinctively positive moderate correlation of morning and afternoon cortisol levels that was observed in healthy women was absent in the CFS group. This may indicate a disturbed physiological rhythm of cortisol secretion. Although basal serum T4, T3, and TSH levels were normal in all subjects, concentrations of T3 were significantly lower in the CFS group.

Conclusion: One-time hormone measurement is not sufficient to detect hormonal imbalance in women suffering from CFS. Absence of a correlation between afternoon and morning cortisol level could be a more representative factor for detecting HPA axis disturbance.

Source: Slavica TOMIC, Snezana BRKIC, Dajana LENDAK, Daniela MARIC, Milica MEDIC STOJANOSKA, Aleksandra NOVAKOV MIKIC. Neuroendocrine disorder in chronic fatigue syndrome. Turkish Journal of Medical Sciences.

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Chronic Fatigue Syndrome Linked To Impaired Stress Response

Subtle alterations of a hormonal stress response system called the HPA axis may play a role in chronic fatigue syndrome, according to a study in the November/December issue of Psychosomatic Medicine.

A smoothly functioning hypothalamus-pituitary-adrenal, or HPA, axis helps the body remain stable under physiological and psychological stress through the actions of three hormones. First, the brain portion called the hypothalamus secretes a hormone that stimulates the pituitary gland to secrete a second hormone. This second hormone causes the adrenal glands to create cortisol.

Problems can occur at any point in this process and result in a variety of diseases. A research team led by Jens Gaab, Ph.D., of the Center for Psychobiological and Psychosomatic Research at the University of Trier in Trier, Germany; and the Institute of Psychology at the University of Zürich in Switzerland are proposing that chronic fatigue syndrome may be one of them.

Chronic fatigue syndrome is characterized by debilitating fatigue that can include including muscle aches, low-grade fever and sleep disturbances. Its cause is not understood.

Gaab and colleagues recruited approximately 40 study participants between the ages of 30 and 50. Half of the participants were chronic fatigue sufferers and the other half were healthy volunteers. All participants completed questionnaires measuring fatigue, depression and coping skills.

To examine the HPA axis in action, participants were given blood, cardiovascular and saliva tests before and after taking two stress tests. The first, a psychosocial stress test, involved preparing for a fake job interview and completing an arithmetic problem before an audience while under the impression they were being videotaped. The second test measured physical stress on a stationary bicycle.

Participants were also given a series of insulin injections known as the insulin tolerance test. “The ITT is considered the gold standard for testing the integrity of the entire HPA axis,” Gaab says.

The researchers found significantly lower response levels of one of the HPA hormones, called ACTH, among the chronic fatigue patients compared with the healthy volunteers, during both stress tests as well as the ITT test. In fact, the chronic fatigue patients had significantly lower levels of the hormone before the testing even began.

“These results suggest that on a central level, subtle dysregulations of the HPA axis exist” in chronic fatigue syndrome patients, Gaab says, adding that future studies should include repeated evaluation of the HPA axis over the course of the syndrome.

Gaab and colleagues note that the possible role of cortisol in chronic fatigue syndrome still merits investigation, as low doses of hydrocortisone have shown some positive results in chronic fatigue patients.

Source: Center For The Advancement Of Health. “Chronic Fatigue Syndrome Linked To Impaired Stress Response.” ScienceDaily. ScienceDaily, 27 November 2002. https://www.sciencedaily.com/releases/2002/11/021126202215.htm

Altered neuroendocrine control and association to clinical symptoms in adolescent chronic fatigue syndrome: a cross-sectional study

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) is a common and disabling disorder, and a major threat against adolescent health. The pathophysiology is unknown, but alteration of neuroendocrine control systems might be a central element, resulting in attenuation of the hypothalamus-pituitary-adrenalin (HPA) axis and enhancement of the sympathetic/adrenal medulla (SAM) system. This study explored differences in neuroendocrine control mechanisms between adolescent CFS patients and healthy controls, and whether characteristics of the control mechanisms are associated with important clinical variables within the CFS group.

METHODS: CFS patients 12-18 years of age were recruited nation-wide to a single referral center as part of the NorCAPITAL project. A broad case definition of CFS was applied. A comparable group of healthy controls were recruited from local schools. A total of nine hormones were assayed and subjected to network analyses using the ARACNE algorithm. Symptoms were charted by a questionnaire, and daily physical activity was recorded by an accelerometer.

RESULTS: A total of 120 CFS patients and 68 healthy controls were included. CFS patients had significantly higher levels of plasma norepinephrine, plasma epinephrine and plasma FT4, and significantly lower levels of urine cortisol/creatinine ratio. Subgrouping according to other case definitions as well as adjusting for confounding factors did not alter the results. Multivariate linear regression models as well as network analyses revealed different interrelations between hormones of the HPA axis, the SAM system, and the thyroid system in CFS patients and healthy controls. Also, single hormone degree centrality was associated with clinical markers within the CFS group.

CONCLUSION: This study reveals different interrelation between hormones of the HPA axis, the SAM system, and the thyroid system in CFS patients and healthy controls, and an association between hormone control characteristics and important clinical variables in the CFS group. These results add to the growing insight of CFS disease mechanisms.

Trial registration Clinical Trials NCT010404

 

Source: Wyller VB, Vitelli V, Sulheim D, Fagermoen E, Winger A, Godang K, Bollerslev J. Altered neuroendocrine control and association to clinical symptoms in adolescent chronic fatigue syndrome: a cross-sectional study. J Transl Med. 2016 May 5;14(1):121. doi: 10.1186/s12967-016-0873-1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4858924/ (Full article)

 

Modeling diurnal hormone profiles by hierarchical state space models

Abstract:

Adrenocorticotropic hormone (ACTH) diurnal patterns contain both smooth circadian rhythms and pulsatile activities. How to evaluate and compare them between different groups is a challenging statistical task. In particular, we are interested in testing (1) whether the smooth ACTH circadian rhythms in chronic fatigue syndrome and fibromyalgia patients differ from those in healthy controls and (2) whether the patterns of pulsatile activities are different. In this paper, a hierarchical state space model is proposed to extract these signals from noisy observations. The smooth circadian rhythms shared by a group of subjects are modeled by periodic smoothing splines. The subject level pulsatile activities are modeled by autoregressive processes. A functional random effect is adopted at the pair level to account for the matched pair design. Parameters are estimated by maximizing the marginal likelihood. Signals are extracted as posterior means. Computationally efficient Kalman filter algorithms are adopted for implementation. Application of the proposed model reveals that the smooth circadian rhythms are similar in the two groups but the pulsatile activities in patients are weaker than those in the healthy controls.

Copyright © 2015 John Wiley & Sons, Ltd.

 

Source: Liu Z, Guo W. Modeling diurnal hormone profiles by hierarchical state space models. Stat Med. 2015 Oct 30;34(24):3223-34. doi: 10.1002/sim.6579. Epub 2015 Jul 7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4592415/ (Full article)

 

Stress management skills, cortisol awakening response, and post-exertional malaise in Chronic Fatigue Syndrome

Abstract:

Chronic Fatigue Syndrome (CFS) is characterized in part by debilitating fatigue typically exacerbated by cognitive and/or physical exertion, referred to as post-exertional malaise (PEM). In a variety of populations, the cortisol awakening response (CAR) has stood out as a marker of endocrine dysregulation relevant to the experience of fatigue, and may therefore be particularly relevant in CFS.

This is the first study to examine PEM and the CAR in a sample of individuals with CFS. The CAR has also been established as a stress-sensitive measure of HPA axis functioning. It follows that better management of stress could modulate the CAR, and in turn PEM. In this cross-sectional study, we hypothesized that greater Perceived Stress Management Skills (PSMS) would relate to lower reports of PEM, via the impact of PSMS on the CAR.

A total of 117 adults (72% female) with a CFS diagnosis completed self-report measures of PSMS and PEM symptomatology and a two-day protocol of saliva collection. Cortisol values from awakening and 30 min post-awakening were used to compute the CAR. Regression analyses revealed that greater PSMS related to greater CAR and greater CAR related to less PEM severity. Bootstrapped analyses revealed an indirect effect of PSMS on PEM via the CAR, such that greater PSMS related to less PEM, via a greater CAR. Future research should examine these trends longitudinally and whether interventions directed at improving stress management skills are accompanied by improved cortisol regulation and less PEM in individuals with CFS.

Copyright © 2014 Elsevier Ltd. All rights reserved.

 

Source: Hall DL, Lattie EG, Antoni MH, Fletcher MA, Czaja S, Perdomo D, Klimas NG. Stress management skills, cortisol awakening response, and post-exertional malaise in Chronic Fatigue Syndrome. Psychoneuroendocrinology. 2014 Nov;49:26-31. doi: 10.1016/j.psyneuen.2014.06.021. Epub 2014 Jul 6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4165790/ (Full article)

 

The role of hypocortisolism in chronic fatigue syndrome

Abstract:

BACKGROUND: There is accumulating evidence of hypothalamic-pituitary-adrenal (HPA) axis hypofunction in chronic fatigue syndrome (CFS). However, knowledge of this hypofunction has so far come exclusively from research in adulthood, and its clinical significance remains unclear. The objective of the current study was to assess the role of the HPA-axis in adolescent CFS and recovery from adolescent CFS.

METHOD: Before treatment, we compared the salivary cortisol awakening response of 108 diagnosed adolescent CFS patients with that of a reference group of 38 healthy peers. Salivary cortisol awakening response was measured again after 6 months of treatment in CFS patients.

RESULTS: Pre-treatment salivary cortisol levels were significantly lower in CFS-patients than in healthy controls. After treatment recovered patients had a significant rise in salivary cortisol output attaining normalization, whereas non-recovered patients improved slightly, but not significantly. The hypocortisolism found in CFS-patients was significantly correlated to the amount of sleep. Logistic regression analysis showed that an increase of one standard deviation in the difference between pre- and post-treatment salivary cortisol awakening response was associated with a 93% higher odds of recovery (adjusted OR 1.93 (1.18 to 3.17), p=0.009). Pre-treatment salivary cortisol did not predict recovery.

CONCLUSIONS: Hypocortisolism is associated with adolescent CFS. It is not pre-treatment cortisol but its change to normalization that is associated with treatment success. We suggest that this finding may have clinical implications regarding the adaptation of future treatment strategies.

Copyright © 2014 Elsevier Ltd. All rights reserved.

 

Source: Nijhof SL, Rutten JM, Uiterwaal CS, Bleijenberg G, Kimpen JL, Putte EM. The role of hypocortisolism in chronic fatigue syndrome. Psychoneuroendocrinology. 2014 Apr;42:199-206. doi: 10.1016/j.psyneuen.2014.01.017. Epub 2014 Jan 30. https://www.ncbi.nlm.nih.gov/pubmed/24636516

 

A role for homeostatic drive in the perpetuation of complex chronic illness: Gulf War Illness and chronic fatigue syndrome

Erratum in

  • PLoS One. 2014;9(4):e94161.
  • PLoS One. 2014;9(6):e100355.

Abstract:

A key component in the body’s stress response, the hypothalamic-pituitary-adrenal (HPA) axis orchestrates changes across a broad range of major biological systems. Its dysfunction has been associated with numerous chronic diseases including Gulf War Illness (GWI) and chronic fatigue syndrome (CFS). Though tightly coupled with other components of endocrine and immune function, few models of HPA function account for these interactions.

Here we extend conventional models of HPA function by including feed-forward and feedback interaction with sex hormone regulation and immune response. We use this multi-axis model to explore the role of homeostatic regulation in perpetuating chronic conditions, specifically GWI and CFS. An important obstacle in building these models across regulatory systems remains the scarcity of detailed human in vivo kinetic data as its collection can present significant health risks to subjects. We circumvented this using a discrete logic representation based solely on literature of physiological and biochemical connectivity to provide a qualitative description of system behavior. This connectivity model linked molecular variables across the HPA axis, hypothalamic-pituitary-gonadal (HPG) axis in men and women, as well as a simple immune network. Inclusion of these interactions produced multiple alternate homeostatic states and sexually dimorphic responses.

Experimental data for endocrine-immune markers measured in male GWI subjects showed the greatest alignment with predictions of a naturally occurring alternate steady state presenting with hypercortisolism, low testosterone and a shift towards a Th1 immune response. In female CFS subjects, expression of these markers aligned with an alternate homeostatic state displaying hypocortisolism, high estradiol, and a shift towards an anti-inflammatory Th2 activation. These results support a role for homeostatic drive in perpetuating dysfunctional cortisol levels through persistent interaction with the immune system and HPG axis. Though coarse, these models may nonetheless support the design of robust treatments that might exploit these regulatory regimes.

 

Source: Craddock TJ, Fritsch P, Rice MA Jr, del Rosario RM, Miller DB, Fletcher MA, Klimas NG, Broderick G. A role for homeostatic drive in the perpetuation of complex chronic illness: Gulf War Illness and chronic fatigue syndrome. PLoS One. 2014 Jan 8;9(1):e84839. doi: 10.1371/journal.pone.0084839. ECollection 2014. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3885655/ (Full article)

 

Unstimulated cortisol secretory activity in everyday life and its relationship with fatigue and chronic fatigue syndrome: a systematic review and subset meta-analysis

Abstract:

The hypothalamic-pituitary-adrenal (HPA) axis is a psychoneuroendocrine regulator of the stress response and immune system, and dysfunctions have been associated with outcomes in several physical health conditions. Its end product, cortisol, is relevant to fatigue due to its role in energy metabolism.

The systematic review examined the relationship between different markers of unstimulated salivary cortisol activity in everyday life in chronic fatigue syndrome (CFS) and fatigue assessed in other clinical and general populations. Search terms for the review related to salivary cortisol assessments, everyday life contexts, and fatigue. All eligible studies (n=19) were reviewed narratively in terms of associations between fatigue and assessed cortisol markers, including the cortisol awakening response (CAR), circadian profile (CP) output, and diurnal cortisol slope (DCS).

Subset meta-analyses were conducted of case-control CFS studies examining group differences in three cortisol outcomes: CAR output; CAR increase; and CP output. Meta-analyses revealed an attenuation of the CAR increase within CFS compared to controls (d=-.34) but no statistically significant differences between groups for other markers. In the narrative review, total cortisol output (CAR or CP) was rarely associated with fatigue in any population; CAR increase and DCS were most relevant.

Outcomes reflecting within-day change in cortisol levels (CAR increase; DCS) may be the most relevant to fatigue experience, and future research in this area should report at least one such marker. Results should be considered with caution due to heterogeneity in one meta-analysis and the small number of studies.

Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

 

Source: Powell DJ, Liossi C, Moss-Morris R, Schlotz W. Unstimulated cortisol secretory activity in everyday life and its relationship with fatigue and chronic fatigue syndrome: a systematic review and subset meta-analysis. Psychoneuroendocrinology. 2013 Nov;38(11):2405-22. doi: 10.1016/j.psyneuen.2013.07.004. Epub 2013 Aug 2. http://www.psyneuen-journal.com/article/S0306-4530(13)00254-0/fulltext (Full article)

 

Norepinephrine and epinephrine responses to physiological and pharmacological stimulation in chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is characterized by fatigue lasting 6 months or longer. CFS has been associated with a disturbed (re-)activity of the autonomic nervous system. However, the sympathetic adrenomedulla (SAM) remains under-examined in CFS.

To investigate SAM reactivity, we implemented a submaximal cycle ergometry (ERGO) and a pharmacological test (Insulin Tolerance Test, ITT) in 21 CFS patients and 20 age-, sex-, and BMI-matched controls. Plasma norepinephrine and epinephrine were collected once before and twice after the tests (+10/+20, and +30 min).

Lower baseline levels and attenuated responses of epinephrine to the ERGO were found in CFS patients compared to controls, while the groups did not differ in their responses to the ITT.

To conclude, we found evidence of altered sympathetic-neural and SAM reactivity in CFS. Exercise stress revealed a subtle catecholaminergic hyporeactivity in CFS patients. It is conceivable that inadequate catecholaminergic responses to physical exertion might contribute to CFS symptoms.

Copyright © 2013 Elsevier B.V. All rights reserved.

 

Source: Strahler J, Fischer S, Nater UM, Ehlert U, Gaab J. Norepinephrine and epinephrine responses to physiological and pharmacological stimulation in chronic fatigue syndrome. Biol Psychol. 2013 Sep;94(1):160-6. doi: 10.1016/j.biopsycho.2013.06.002. Epub 2013 Jun 13. https://www.ncbi.nlm.nih.gov/pubmed/23770415