Alternate day prednisone therapy in congenital adrenal hyperplasia: adrenal androgen suppression and normal growth

Daily glucocorticoid therapy of children with congenital adrenal hyperplasia (CAH) frequently results in a suboptimal mature height. In contrast, pharmacological doses of prednisone given on alternate days generally allow normal growth in children with autoimmune, hematological, and renal disorders. Moreover, alternate day prednisone therapy suppresses adrenal androgen secretion on both the day on and the day off therapy in patients with systemic lupus erythematosus. We hypothesized that alternate day prednisone therapy might be efficacious in the treatment of CAH. To evaluate this hypothesis, we studied an 11-yr-old girl with salt-losing 21-hydroxylase deficiency and severe asthma treated with alternate day prednisone therapy (20 mg every other day) for over 3 yr. During this period her linear growth was along the 65th percentile, and her bone age paralleled her chronological age. Pubertal development was normal, and she had no signs of androgen or glucocorticoid excess. In keeping with her clinical picture, basal (24-h samples drawn every 60 min) and ovine CRH-stimulated plasma adrenal androgen (dehydroepiandrosterone sulfate and delta 4-androstenedione) concentrations and 24-h urinary 17-ketosteroid excretion were low on both the day on and the day off prednisone. However, her plasma ACTH and 17-hydroxyprogesterone levels were markedly elevated on both days. The adrenal androgen suppression, therefore, appeared independent of the level of ACTH, suggesting different regulation of the zona fasciculata and the zona reticularis. GH secretion, assessed by measurement of plasma GH every 20 min for 48 h, was normal on both the on and off days of prednisone therapy. Therefore, in this girl pharmacological doses of prednisone given on alternate days caused sustained adrenal androgen suppression and allowed normal growth and pubertal development, despite persistently elevated plasma ACTH and 17-hydroxyprogesterone levels.     

Impaired endothelial function in young women with premature ovarian failure: normalization with hormone therapy

Normal menopause is associated with vascular endothelial dysfunction, an early stage of atherosclerosis. The effect of premature ovarian failure (or premature menopause) on endothelial function in young women is unknown. Endothelial function was assessed in 18 women with premature ovarian failure before and after 6 months of hormone therapy and was compared with the endothelial function of 20 age- and body mass index-matched premenopausal women. Brachial artery diameter was measured both during hyperemia (an index of endothelium-dependent vasodilation) and in response to glyceryl trinitrate (an index of endothelium-independent vaso-dilation). Flow-mediated dilation was significantly lower in women with premature ovarian failure at baseline (increase in brachial artery diameter during hyperemia by 3.06 +/- 4.33%) than in control women (increase by 8.84 +/- 2.15%; P < 0.0005). Glyceryl trinitrate-induced vasodilation did not differ between the groups. After hormone therapy for 6 months, flow-mediated dilation was improved in women with premature ovarian failure, increasing by more than 2-fold (7.41 +/- 3.86%; P < 0.005 compared with pretreatment) and reaching normal values (P not significant compared with control women). Glyceryl trinitrate-induced vasodilation did not change after treatment in women with premature ovarian failure. Young women with premature ovarian failure have significant vascular endothelial dysfunction. Early onset of endothelial dysfunction associated with sex steroid deficiency may contribute to the increased risk of cardiovascular disease and mortality in young women with premature ovarian failure. Hormone therapy restores endothelial function within 6 months of treatment.     

Stress dose of hydrocortisone is not beneficial in patients with classic congenital adrenal hyperplasia undergoing short-term, high-intensity exercise

Classic congenital adrenal hyperplasia (CAH) is associated with impaired function of the adrenal cortex and medulla leading to decreased production of cortisol and epinephrine. As a result, the normal exercise-induced rise in blood glucose is markedly blunted in such individuals. We examined whether an extra dose of hydrocortisone, similar to that given during other forms of physical stress such as intercurrent illness, would normalize blood glucose levels during exercise in patients with CAH. We studied hormonal, metabolic, and cardiorespiratory parameters in response to a standardized high-intensity exercise protocol in nine adolescent patients with classic CAH. Patients were assigned to receive either an additional morning dose of hydrocortisone or placebo, in addition to their usual glucocorticoid and mineralocorticoid replacement in a randomized, double-blind, crossover design 1 h before exercising. Although plasma cortisol levels approximately doubled after administration of the additional hydrocortisone dose compared with the usual single dose, fasting and exercise-induced blood glucose levels did not differ. In addition, no differences were observed in the serum concentrations of the glucose-modulating hormones epinephrine, insulin, glucagon, and GH and of the metabolic parameters lactate and free fatty acids. Although maximal heart rate was slightly higher after stress dosing (193 +/- 3 vs. 191 +/- 3 beats/min, mean +/- sem, P < 0.05), this did not affect exercise performance or perceived exertion. We conclude that patients with classic CAH do not benefit from additional hydrocortisone during short-term, high-intensity exercise. Although this has not been tested with long-term exercise, a high degree of caution should be used when considering the frequent use of additional hydrocortisone administration with exercise, given the adverse side effects of glucocorticoid excess.     

Morning preprandial plasma ghrelin and catecholamine concentrations in patients with phenylketonuria and normal controls: evidence for catecholamine-mediated ghrelin regulation

Patients with phenylketonuria (PKU) have a diet-controlled deficiency in the conversion of phenylalanine (Phe) to tyrosine (Tyr), leading to decreased production of noradrenaline, adrenaline, and dopamine. Poor diet control results in high plasma Phe and low plasma Tyr and catecholamine concentrations. Ghrelin, a recently described gastrointestinal hormone that is elevated in the fasting state and low in the fed state, is considered a major appetite-stimulating hormone, possibly involved in the generation of obesity and insulin resistance. We evaluated morning preprandial plasma ghrelin levels in 14 diet-controlled and 15 poorly controlled PKU patients and 20 age- and body mass index (BMI)-matched healthy children (controls) and correlated its concentrations with those of Phe and catecholamines as well as with their BMI and 24-h nutrient intake. Plasma ghrelin levels were measured by RIA, plasma catecholamine concentrations were determined by HPLC with electrochemical detection, and Phe and Tyr levels were measured in an amino acid analyzer. The ghrelin concentration (744 +/- 25 ng/liter) in diet-controlled patients did not differ from that in controls (802 +/- 26 ng/liter; P > 0.05). On the contrary, the ghrelin concentration was significantly reduced in poorly controlled patients (353 +/- 23 ng/liter; P < 0.0001). Ghrelin correlated negatively with Phe in all three groups, whereas it correlated positively with catecholamine levels and energy intake and negatively with BMI only in diet-controlled patients and controls. We conclude that ghrelin secretion may receive positive direct or indirect input from catecholamines. The absence of a correlation between ghrelin and catecholamines, energy intake, or BMI in PKU patients on an inadequate diet may be due to dysregulation of their neuroendocrine system and might be affected by high Phe levels in the stomach and/or central nervous system.     

Responses of the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis to interleukin-6: a pilot study in fibromyalgia

OBJECTIVE: To determine whether deficient activity of the hypothalamic corticotropin-releasing hormone (CRH) neuron, which stimulates the hypothalamic-pituitary-adrenal (HPA) axis and the central control nuclei of the sympathetic nervous system and inhibits ascending pain pathways, may be pathogenic in patients with fibromyalgia (FM). METHODS: We administered interleukin-6 (IL-6; 3 microg/kg of body weight subcutaneously), a cytokine capable of stimulating hypothalamic CRH release, and measured plasma levels of adrenocorticotropic hormone (ACTH), cortisol, and catecholamines and their metabolites and precursors. Thirteen female FM patients and 8 age- and body mass index-matched female controls were studied. The diagnosis of FM was made according to American College of Rheumatology criteria. Tender points were quantitated by pressure algometry. All subjects had HPA axis studies. Seven FM patients and 7 controls also had catecholamine measurements. RESULTS: After IL-6 injection, delayed ACTH release was evident in the FM patients, with peak levels at 96.9 +/- 6.0 minutes (mean +/- SEM; control peak 68.6 +/- 10.3 minutes; P = 0.02). Plasma cortisol responses to IL-6 did not differ significantly between patients and controls. Basal norepinephrine (NE) levels were higher in the FM patients than in the controls. While a small, although not significant, rise in NE levels occurred after IL-6 injection in the controls, NE levels dramatically increased over basal levels in the FM patients between 60 and 180 minutes after IL-6 injection. Both peak NE levels (mean +/- SEM 537.6 +/- 82.3 versus 254.3 +/- 41.6 pg/ml; P = 0.0001) and time-integrated NE responses (93.2 +/- 16.6 pg/ml x minutes(-3) versus 52.2 +/- 5.7 pg/ml x minutes(-3); P = 0.038) were greater in FM patients than in controls. Heart rate was increased by IL-6 injection in FM patients and controls, but rose to significantly higher levels in the FM patients from 30 minutes to 180 minutes after IL-6 injection (P < 0.03). CONCLUSION: Exaggerated NE responses and heart rate increases, as well as delayed ACTH release, were observed among female FM patients compared with age-matched female controls. Delayed ACTH release after IL-6 administration in FM is consistent with a defect in hypothalamic CRH neuronal function. Exaggerated NE release may reflect abnormal regulation of the sympathetic nervous system, perhaps secondary to chronically deficient hypothalamic CRH. The excessive heart rate response after IL-6 injection in FM patients may be unrelated to the increase in NE, or it may reflect an alteration in the sensitivity of cardiac beta-adrenoceptors to NE. These responses to a physiologic stressor support the notion that FM may represent a primary disorder of the stress system.     

Glucocorticoid replacement is permissive for rapid eye movement sleep and sleep consolidation in patients with adrenal insufficiency

There is a well described temporal relation between hormonal secretion and sleep phase, with hormones of the hypothalamic-pituitary-adrenal (HPA) axis possibly playing a role in determining entry into and duration of different sleep stages. In this study sleep features were studied in primary Addison's patients with undetectable levels of cortisol treated in a double blind, randomized, cross-over fashion with either hydrocortisone or placebo supplementation. We found that REM latency was significantly decreased in Addison's patients when receiving hydrocortisone at bedtime, whereas REM sleep time was increased. There was a trend toward an increase in the percentage of time in REM sleep and the number of REM sleep episodes. Waking time after sleep onset was increased, whereas no differences were observed between the two conditions when total sleep time or specific non-REM sleep parameters were evaluated. Our results suggest that in Addison's patients, cortisol plays a positive, permissive role in REM sleep regulation and may help to consolidate sleep. These effects may be mediated either directly by the central effects of glucocorticoids and/or indirectly through CRH and/or ACTH.     

Impaired nighttime sleep in healthy old versus young adults is associated with elevated plasma interleukin-6 and cortisol levels: physiologic and therapeutic implications

IL-6 and TNF alpha secretion is increased by sleep loss or restriction. IL-6 secretion progressively increases with age, yet its association with decreased quality and quantity of sleep in old adults is unknown. This study examined the alteration of 24-h secretory pattern of IL-6, TNF alpha, and cortisol in 15 young and 13 old normal sleepers who were recorded in the sleep laboratory for four consecutive nights. Serial 24-h plasma measures of IL-6, TNF alpha, and cortisol were obtained during the fourth day, and daytime sleepiness was assessed with the multiple sleep latency test. Old adults, compared with young subjects, slept poorly at night (wake time and percentage stage 1 sleep were increased, whereas their percentage slow wave sleep and percentage sleep time were decreased, P < 0.05). Accordingly, their daytime sleep latency was longer than in young adults (P < 0.05). The mean 24-h IL-6 and cortisol levels were significantly higher in old than young adults (P < 0.05). In both groups, IL-6 and cortisol plasma concentrations were positively associated with total wake time, with a stronger association of IL-6 and cortisol with total wake time in the older individuals (P < 0.05); their combined effect was additive. IL-6 had a negative association with rapid eye movement (REM) sleep only in the young (P < 0.05), but cortisol was associated negatively with REM sleep both in the young and old, with a stronger effect in the young. We conclude that in healthy adults, age-related alterations in nocturnal wake time and daytime sleepiness are associated with elevations of both plasma IL-6 and cortisol concentrations, but REM sleep decline with age is primarily associated with cortisol increases.     

Corticotropin releasing hormone (CRH) antagonist attenuates adjuvant induced arthritis: role of CRH in peripheral inflammation

OBJECTIVE: To determine whether a corticotropin releasing hormone (CRH) type 1-specific receptor antagonist, antalarmin, would alter the progression of inflammation in adjuvant induced arthritis (AIA) susceptible LEW/N rats by blocking local CRH mediated inflammatory responses or render AIA resistant F344/N rats more susceptible to AIA by blocking central CRH, thus reducing secretion of endogenous glucocorticoids. METHODS: F344/N and LEW/N rats were assigned to either drug or vehicle groups and treated with 20 mg/kg antalarmin or vehicle alone BID for 25 days by intraperitoneal injection. Arthritis was induced in both antalarmin and vehicle treated LEW/N and F344/N rats by subcutaneous injections at the base of the tail of incomplete Freund's adjuvant containing 10 mg/ml heat killed Mycobacterium tuberculosis. Control F344/N and LEW/N rats were maintained on either antalarmin or vehicle. RESULTS: Chronic blockade of CRH-R1 with systemic antalarmin significantly ameliorated AIA in LEW/N rats, reducing the severity of inflammation in peripheral joints, evidenced by clinical and histopathology scores, and weight loss associated with disease onset. Antalarmin neither induced nor exacerbated arthritis expression in F344/N or LEW/N rats, despite suppression of levels of adjuvant induced corticosterone, the major antiinflammatory glucocorticoid in rats. CONCLUSION: Systemic blockade of CRH-RI appeared to predominantly block peripheral proinflammatory effects of immune CRH, rather than the systemic glucocorticoid mediated antiinflammatory effects of hypothalamic CRH. Results indicate that chronic treatment with a CRH antagonist attenuates progressive inflammation induced degeneration of synovia, cartilage, and bone in arthritic joints, suggesting that antalarmin may have therapeutic potential in treatment of human autoimmune and inflammatory disorders.     

Chronic insomnia is associated with a shift of interleukin-6 and tumor necrosis factor secretion from nighttime to daytime

Chronic insomnia, by far the most commonly encountered sleep disorder in medical practice, is characterized by difficulty falling or staying asleep at night and increased fatigue during the day. Interleukin-6 (IL-6) and tumor necrosis factor (TNF) are fatigue-inducing cytokines, and the daytime secretion of IL-6 is negatively influenced by the quantity and quality of the previous night's sleep. We hypothesize that the poor quality of insomniacs' sleep is associated with a hypersecretion of these 2 cytokines during the daytime, which, in turn, correlates with the fatigue experienced by these patients. Eleven young insomniacs (6 men and 5 women) and 11 (8 men and 3 women) age- and body mass index (BMI)-matched healthy controls participated in the study. Subjects were recorded in the sleep laboratory for 4 consecutive nights and serial 24-hour plasma measures of IL-6 and TNF were obtained during the 4th day. Insomniacs compared to controls slept poorly (sleep latency and wake were increased, whereas percentage sleep time was decreased during baseline nights, all P <.05). The mean 24-hour IL-6 and TNF secretions were not different between insomniacs and controls. However, the difference in the change (increase) of IL-6 plasma levels from midafternoon (2 PM) to evening (9 PM) between insomniacs and controls was significant (P <.01). Furthermore, cosinor analysis showed a significant shift of the major peak of IL-6 secretion from nighttime (4 AM) to evening (7 PM) in insomniacs compared to controls (P <.05). Also, while TNF secretion in controls showed a distinct circadian rhythm with a peak close and prior to the offset of sleep (P <.05), such a rhythm was not present in insomniacs. Finally, daytime secretion of TNF in insomniacs was characterized by a regular rhythm of 4 hours (P <.05); such a distinct periodicity was not present in controls. We conclude that chronic insomnia is associated with a shift of IL-6 and TNF secretion from nighttime to daytime, which may explain the daytime fatigue and performance decrements associated with this disorder. The daytime shift of IL-6 and TNF secretion, combined with a 24-hour hypersecretion of cortisol, an arousal hormone, may explain the insomniacs' daytime fatigue and difficulty falling asleep.