Plasma levels of adrenomedullin in patients with adrenoleukodystrophy/adrenomyeloneuropathy.

BACKGROUND/AIMS: Adrenomedullin (AM) is a recently purified hypotensive peptide and its encoding gene has been sequenced from a human pheochromocytoma. High levels of AM have been shown in Addison's disease (AD). X-linked adrenoleukodystrophy/adrenomyeloneuropathy (ALD/AMN) is a peculiar adrenal insufficiency due to an accumulation of very-long chain fatty acid in adrenal cells and it is very often associated with a devastating demyelination of the central nervous system. METHODS: We studied the AM plasma levels of 22 patients with ALD/AMN (18 with hypoadrenalism, ALDa, and 4 with normal adrenal function, ALDb) and compared them with 18 males with classical AD and 16 normal male subjects. All patients with hyposurrenalism were studied before treatment with hydrocortisone. RESULTS: Both patients with ALD/AMN and AD showed increased levels of AM and all of them showed a significant difference from the control group (p < 0.0001). The plasma renin activity was higher in all patient groups than in the control group (p <0.001 ALDa, ALDb and AD vs. control group). The aldosterone levels were higher in ALDa and ALDb groups than AD (ALDa vs. AD p < 0.01; ALDb vs. control group p < 0.05; AD vs. controls p < 0.01). ACTH plasma levels were higher in ALDa and AD than ALDb and the control group (ALDa vs. AD not significant while ALDa and AD vs. control p <0.0001). CONCLUSIONS: Our data indicate that plasma AM levels in ALDa, ALDb and AD are higher than controls. These results were previously described in untreated AD. While classical AD patients show complete adrenal insufficiency (both mineralocorticoid and glucocorticoid defects), ALD/AMN patients show a less compromised glomerular function, indicating that AM is not completely correlated with mineralocorticoid insufficiency, and that the exact mechanism responsible for the increased AM levels in ALD/AMN is still unknown.

Adrenomedullin concentrations are elevated in plasma of patients with primary hyperparathyroidism.

The aim of the study was to evaluate plasma adrenomedullin (AM) concentration in primary hyperparathyroidism (PHP) and its effect on the regulation of blood pressure. Forty-one patients with PHP (25 normotensive and 16 hypertensive), and 31 healthy subjects (HS) were included in the study. As expected the total and ionized calcium and i-PTH serum levels were significantly higher in patients with PHP than in HS (P <.001). No significant difference was found in calcium-phosphorus metabolism parameters between normotensive and hypertensive PHP patients. Serum i-PTH levels correlated positively with systolic blood pressure (SBP) (r = 0.510; P <.02), diastolic blood pressure (DBP) (r = 0.586; P <.01) and heart rate (HR) (r = 0.486; P <.043) only in hypertensive PHP patients. Overall, mean plasma AM concentrations were significantly higher in PHP patients (16.1 +/- 7.9 pg/mL) than in HS (11.3 +/- 4.8 pg/mL) (P <.003) and correlated with i-PTH (r = 0.430; P <.005). However, in hypertensive PHP patients plasma AM levels (22.5 +/- 4.7 pg/mL) were higher than in normotensive PHP patients (11.6 +/- 1.8 pg/mL) (P <.001) and correlated with DBP (r = 0.902, P <.0029). In HS no correlation was found between plasma AM values and biohumoral, hormonal, or hemodynamic parameters. In conclusion, we demonstrated that in patients with PHP, plasma AM concentrations are increased and correlate with i-PTH and blood pressure values. We suggest that increased AM levels could be a compensatory factor in the defence mechanism against further blood pressure elevation.

Plasma levels of endothelin-1 increase in patients with sarcoidosis and fall after disease remission.

BACKGROUND: Sarcoidosis is a chronic systemic disease, characterized by an imbalance of immunity processes and the presence of granuloma. Endothelin-1, a new vasoactive and bronchoconstrictive peptide, is a powerful mitogen for smooth muscle cells and fibroblasts and plays a role in the inflammation state. We postulate that endothelin-1 has a role in sarcoidosis. METHODS: We studied the behaviour of circulating levels of endothelin-1 in 20 patients with sarcoidosis and its correlation with some biochemical parameters of activity disease, such as erythrocyte sedimentation rate (ESR) and serum angiotensin-converting enzyme (SACE). We measured serum levels of ESR, SACE, calcium and plasma endothelin-1 levels in all patients at the beginning of the study and one again in 9 patients with clinical-biochemical remission of disease after steroid treatment. RESULTS: In patients with sarcoidosis, circulating levels of endothelin-1, SACE and ESR were significantly higher (p<0.001) than those of healthy subjects. Moreover, in patients with pulmonary involvement, there was a significant statistical difference (p<0.001) between endothelin-1 levels and radiological stage compared to normal subjects. In the 9 patients with remission of disease, both endothelin-1 levels and parameters of activity disease normalized. CONCLUSIONS: Our results seem to suggest that the increase of plasma endothelin-1 levels in active sarcoidosis can represent an expression of the endothelial dysfunction and reflect the picture of cellular activation.

[High circulating levels of adrenomedullin and endothelin-1 in obesity associated with arterial hypertension]. / Elevati livelli circolanti di adrenomedullina e di endotelina-1 nell'obesità associata ad ipertensione arteriosa.

BACKGROUND: The aim of the study was to investigate the behavior of two endothelial vasoactive peptides, adrenomedullin (vasodilator) and endothelin-1 (vasoconstrictor), in human obesity with and without arterial hypertension. METHODS: The study was carried out on 30 obese subjects (body mass index > 27 kg/m2) divided into two groups: 15 normotensive obese patients (10 males, 5 females, mean age 42 +/- 12 years) and 15 hypertensive obese patients (9 males, 6 females, mean age 42 +/- 13 years). The control group consisted of 21 normal subjects (12 males, 9 females, mean age 38 +/- 12 years) and of 16 patients with essential hypertension (10 males, 6 females, mean age 41 +/- 12 years) but without organ damage. All studied subjects were taking a normocaloric (20-22 kcal/kg/day), normosodic (120-140 mEq/day) and normopotassic (50-60 mEq/day) diet. Between 8.00 and 9.00 a.m., a venous blood sample was taken for the determination (radioimmunoassay) of plasma adrenomedullin and endothelin-1 concentrations. RESULTS: Plasma adrenomedullin levels in normal subjects (13.7 +/- 6.1 pg/ml) were similar to those in normotensive obese patients (14.8 +/- 7.2 pg/ml), whereas in hypertensive obese patients (22.5 +/- 9.1 pg/ml) and in those with essential hypertension (22.7 +/- 8.2 pg/ml) levels were significantly higher (ANOVA = 0.000, p < 0.05) than those of normal subjects and of normotensive obese patients. Moreover, endothelin-1 plasma concentrations were found to be significantly higher (ANOVA = 0.000, p < 0.05) in hypertensive obese patients (10.3 +/- 2.7 pg/ml) compared to normal subjects (6.5 +/- 2.4 pg/ml), normotensive obese patients (8.3 +/- 1.5 pg/ml) and to those with essential hypertension (8.5 +/- 2.9 pg/ml). In patients with essential hypertension, a positive correlation (r = 0.493, p < 0.05) was found between adrenomedullin and endothelin-1 plasma levels. CONCLUSIONS: These results revealed that in human obesity associated with arterial hypertension there is an increased production of plasma adrenomedullin and endothelin-1 that, with their opposite vasoactive properties (vasodilation/vasoconstriction), can contribute to this pathological association.

Endothelin-1 circulating levels increase in patients with orthotopic heart transplantation and in chronic therapy with cyclosporine.

BACKGROUND: The aim of the study was to investigate the behaviour of plasma levels of endothelin-1 (ET-1), an endothelial peptide with vasoconstrictive and proliferative actions, in patients with cardiac transplantation and in chronic treatment with cyclosporine A, some of whom became hypertensive after cardiac transplantation. METHODS: We studied: 1) 18 consecutive patients (15 M, 3F; mean age 53 +/- 7 yrs) who underwent cardiac transplantation about six months ago at least (range 6-108 months); 2) 15 patients with essential arterial hypertension (10 M, 5 F; mean age 42 +/- 15 yrs) without organ damage; 3) 21 normal subjects (15 M, 6 F; mean age 31 +/- 12 yrs). Plasma levels of ET-1 (RIA), haemodynamic and functional renal parameters were determined in all groups and plasma levels of cyclosporine were measured in patients with cardiac transplantation. RESULTS: ET-1 was higher in patients with cardiac transplantation than in the other two groups (p < 0.05); instead there was no difference between patients with essential arterial hypertension and controls (p>0.05). A statistical difference was found between circulating ET-1 in hypertensive transplanted patients. In heart transplanted patients a positive and significative correlation was found between plasma levels of ET-1 and systolic (r=0.525; p<0.037) blood pressure.

Circulating adrenomedullin is increased in patients with corticotropin-dependent Cushing's syndrome due to pituitary adenoma.

It has been demonstrated that adrenomedullin, a newly discovered peptide with structural similarity to calcitonin gene-related peptide (CGRP), is expressed in pituitary gland and affects basal and corticotropin (ACTH)-releasing factor (CRF)-stimulated ACTH release in animals, thus suggesting its potential role in regulating the hypothalamus-pituitary-adrenal axis. To evaluate whether ACTH and cortisol levels affect adrenomedullin production in humans, we studied 14 patients with Cushing's syndrome due to pituitary adenoma and 8 patients with Cushing's syndrome due to adrenal tumor, with measurement of circulating adrenomedullin by a specific radioimmunoassay (RIA). Adrenomedullin concentrations were significantly higher in patients with pituitary adenoma (37.6 +/- 17.8 pg/mL) versus controls (13.7 +/- 6.1 pg/mL) and patients with adrenal adenoma (17.8 +/- 2.2 pg/mL). After pituitary surgical treatment, plasma adrenomedullin decreased significantly. In one patient with Cushing's syndrome due to pituitary adenoma who underwent simultaneous sampling of the inferior petrosal venous sinuses, the adrenomedullin concentration was significantly higher in plasma collected from the side with the adenoma and increased after CRF administration (delta increase, 42.6%), according to ACTH levels. Our findings indicate that circulating adrenomedullin is increased in Cushing's disease, and the pituitary gland may represent the site of the elevated production of adrenomedullin in this condition.

[Adrenomedullin. A new peptide involved in the regulation of the cardiovascular system]. / Adrenomedullina. Un nuovo peptide coinvolto nella regolazione del sistema cardiovascolare.

Adrenomedullin was originally discovered in human pheochromocytoma but is now known to be widely distributed in various organs. Adrenomedullin is a potent vasodilatator peptide that exerts major effects on cardiovascular function. Plasma adrenomedullin concentration is increased in patients with cardiovascular disease such as hypertension, congestive heart failure, myocardial infarction, renal failure and other diseases. The present review summarizes the recent advances on adrenomedullin research and demonstrates that adrenomedullin is one of the important vasoactive peptides involved in the physiology and pathophysiology of cardiovascular system.

Plasma levels of endothelin-1 in patients with Crohn's disease and ulcerative colitis.

AIM: The purpose of this study was to investigate the behavior of circulating endothelin-1, a vasoconstrictor and mitogenic peptide, in patients with inflammatory bowel disease. PATIENTS: We investigated plasma endothelin-1 levels in 29 patients with Crohn's disease, 13 with ulcerative colitis and 26 healthy subjects as controls. METHODS: Erythrocyte sedimentation and C-reactive protein were also measured in all patients. Plasma endothelin-1 was measured by specific radioimmunoassay and expressed as pg/ml. RESULTS: Both Crohn's disease and ulcerative colitis patients showed a significant increase in plasma endothelin-1 concentration (22.3 +/- 8.2 pg/ml and 11.2 +/- 2.7 pg/ml, respectively) when compared to healthy subjects (6.2 +/- 1.5 pg/ml). Moreover, plasma endothelin-1 levels were significantly higher in Crohn's disease patients than those in ulcerative colitis patients (22.3 +/- 8.2 pg/ml vs 11.2 +/- 2.7 pg/ml; p < 0.001, respectively). A weak correlation (r = 0.645; p < 0.013) between erythrocyte sedimentation and endothelin-1 levels was observed in Crohn's disease patients. Age, sex, clinical activity of the disease, duration of history, anatomical localization of disease and therapy had no influence on plasma endothelin-1 levels. CONCLUSION: Our results show that plasma endothelin-1 levels increase in chronic inflammatory bowel disease and mainly in Crohn's disease. This observation leads us on to believe that endothelin-1 has a important role in inflammatory bowel disease.

Circulating levels of adrenomedullin in patients with Addison's disease before and after corticosteroid treatment.

BACKGROUND AND OBJECTIVE: A novel hypotensive peptide, adrenomedullin (AM), had recently been isolated, purifed and its encoding gene sequenced from a human phaeochromocytoma. In humans AM circulates in physiological levels and possesses a distinct vasodilatatory activity. The purpose of this study was to examine the behaviour of AM levels in primary adrenal failure. DESIGN: Plasma AM levels were measured in patients with proven Addison's disease using a specific radioimmunoassay and compared to those in healthy normotensive subjects. PATIENTS: Eighteen patients with Addison's disease (10 men and eight women; ages 21 to 72 years) and 21 healthy control subjects (13 men and eight women; ages 20 to 71 years) were enrolled in the study. All patients were studied under basal conditions and 10 were reassessed following corticosteroid treatment. RESULTS: All patients with Addison's disease showed increased levels of AM compared to the control group. Mean plasma AM levels were correspondingly higher in patients with Addison's disease than in normal subjects (102.1 +/- 33.4 (SD) ng/l versus 13.7 +/- 6.1 ng/l; P < 0.0001). In 10 patients studied after corticosteroid treatment, plasma AM levels were significantly reduced (P < 0.0001: 110.3 +/- 35.8 ng/l versus 32.4 +/- 10.3 ng/l) after 2 weeks of treatment. A weak correlation (r = 0.458; P = 0.048) was observed between systolic blood pressure and plasma AM concentrations in all patients with Addison's disease. CONCLUSIONS: These results indicate a consistent but reversible increase of adrenomedullin in patients with Addison's disease.

Adrenomedullin levels are high in primary aldosteronism due to adenoma and decline after surgical cure.

The aim of the study was to evaluate the possible changes in plasma adrenomedullin (AM) levels in patients with primary aldosteronism before and after surgical resection. The study included 13 patients affected by aldosterone-producing adenoma (9 women, 4 men; mean age 36.2+/-14.2 years) and 20 healthy control subjects (7 women, 13 M; mean age 31.8+/-12.4 years). Unilateral adrenalectomy was performed in all patients and adrenal mass consisted of a benign adrenal cortical adenoma. The mean plasma AM concentrations in patients with primary aldosteronism (36.2+/-19.3 pg/ml) were significantly (p < 0.0001) higher than those of normal subjects (13.2+/-6.2 pg/ml). In these patients the plasma AM levels significantly (p < 0.0001) reduced after surgical removal of the tumours (14.9+/-7.6 pg/ml). In all patients with aldosterone-producing adenoma, tumour diameter correlated with the plasma AM concentrations (r=0.631; p < 0.021). In conclusion, the present investigation shows that in primary aldosteronism due to adrenal adenoma plasma AM levels are higher at the moment of diagnosis and decline after successful adrenal operation.

False-positive diagnosis of adrenal pheochromocytoma on iodine-123-MIBG scan.

1-123 metaiodobenzylguanidine (1-123 MIBG) scintigraphy is known for its high specificity in detecting pheochromocytoma and other tumors of neural crest origin. In this rare case report, we describe a definite adrenocortical adenoma that demonstrated false-positive uptake at I-123 MIBG scintigraphy and a remarkable accumulation of 75-SE-6-beta-selenomethyl-norcholesterol.

[Behavior of plasma levels of endothelin 1 and noradrenaline in patients with stable angina during the cold pressor test]. / Il comportamento dei livelli plasmatici di endotelina-1 e di noradrenalina nei pazienti con angina stabile in corso di cold pressor test.

The aim of this study was to evaluate the behaviour of plasma endothelin-1 (ET-1) and norepinephrine (NE) levels in patients with stable angina during a sympathetic stimulation test as the cold pressor test. We enrolled in the study 29 subjects: 14 patients with stable angina (all men, mean age 58.3 +/- 7.3 years) and 15 healthy subjects (all men, mean age 54 +/- 5 years). All patients with stable angina had a stenosis of the coronary arteries (at least 70% of the stenosis in one of the coronary arteries) confirmed by angiography. Before (-15 min; 0 min) during (+2 min) and after the cold pressor test (+5 min, +10 min, +20 min, +30 min) were measured the blood pressure and the heart rate. At the same time were collected venous samples for the ET-1 and NE determination. ET-1 levels increased only in the patients with stable angina (ET-1: O' = 9.8 +/- 3.7 pg/ml; +2' = 11.1 +/- 4.5 pg/ml; +10' = 14.8 +/- 7.1 pg/ml; +20' = 11.6 +/- 5.1 pg/ml; p < 0.05 vs 0', +2'; +20'). The NE levels increased in both groups (NE stable angina: 0' = 105 +/- 31 pg/ml; +2' = 206 +/- 127 pg/ml; +5' = 223 +/- 135 pg/ml; p < .05 vs +2', +5'); (NE healthy subjects 0' = 85 +/- 10 pg/ml; +2' 165 +/- 49 pg/ml; p < 0.05 vs + 2'). In conclusion, our study showed that cold pressor test is a stimulus for the sympathetic system in both groups. The increased levels of ET-1 detected only in the patients with stable angina suggest that this peptide can take part to the pathogenesis of the coronary artery disease.