R. Franceschini

Serum leptin levels in patients with viral chronic hepatitis or liver cirrhosis

BACKGROUND/AIM Serum levels of leptin, the adipocyte-derived hormone regulating food intake and energy expenditure in mammals, have been found to be increased in cirrhotic patients. The aim of the present study was to investigate leptin serum level in relation to anthropometric features and liver function in patients with viral chronic hepatitis or liver cirrhosis. METHODS Serum leptin levels were determined by radioimmunoassay in 30 male and 10 female patients with chronic hepatitis, in 42 male and 10 female patients with liver cirrhosis, and in four respective control groups. Liver function was evaluated by the monoethylglycinexylidide formation test. Body mass index and body fat mass were estimated by weight, height and skinfold thickness measurements. RESULTS Compared with controls, absolute serum leptin levels were significantly (p<0.01) lower in chronic hepatitis patients and similar in cirrhotic patients. Leptin serum levels were significantly (p<0.05) higher in cirrhotic than in chronic hepatitis patients. When expressed in relation to body fat mass, the above differences persisted; however, cirrhotic females showed significantly (p<0.05) higher serum leptin values than controls. Serum leptin values correlated negatively (p<0.01) with monoethylglycinexylidide serum values in all groups of patients. CONCLUSIONS In patients with chronic viral liver disease, serum leptin levels tend to increase as liver function worsens. This may reflect a decline in the ability to downregulate energy expenditure as an adaptation to anorexia and/or to defective substrate utilisation due to liver disease and may negatively influence body weight homeostasis in these patients.

24-Hour Thyroid-Stimulating Hormone Secretory Pattern in Elderly Men

A chronobiological study was carried out in 10 elderly male subjects (78-83 years) to evaluate the 24-hour thyroid-stimulating hormone (TSH) secretory pattern. 10 young adult males (26-35 years) made up the control group. Hourly blood samples were drawn from each subject for a 24-hour period. TSH levels in elderly subjects showed blunted circadian fluctuations compared to those seen in young adult subjects. Mean 24-hour TSH values in elderly (3.1 +/- 0.3 microU/ml) and young adult subjects (3.5 +/- 0.1 microU/ml) did not differ statistically, but nighttime TSH values observed in elderly subjects (3.2 +/- 0.3 microU/ml) were lower (p less than 0.05) than those recorded in young adults (4.1 +/- 0.1 microU/ml).

Effects of ursodeoxycholic acid (UDCA) on serum liver damage indices in patients with chronic active hepatitis

SummaryThe effects of ursodeoxycholic acid (UDCA, 450 mg daily) in patients with histologically proven chronic active hepatitis (CAH) have been evaluated in a randomized, double-blind, placebo-controlled study. Twenty-six patients with serum alanine aminotransferase (ALT) values at least twice the normal upper limit in two of three pre-treatment tests received UDCA or a placebo for twelve weeks.In all UDCA-treated patients, serum aspartate aminotransferase (AST), ALT, gamma-glutamyl transpeptidase (GGT) and alkaline phosphatase (AP) fell significantly after 4 weeks of treatment. There was a further decrease at the end of therapy, as well as a small but significant fall in total serum bilirubin. Conversely, 4 weeks aftersuspension of therapy, serum enzyme levels had increased, reaching values not much lower than those recorded before treatment. Total serum protein, albumin and γ-globulin did not change after UDCA treatment. In the placebo group no significant variation in the test results were found.The results indicate that UDCA therapy in CAH, as has been observed in primary biliary cirrhosis and primary sclerosing cholangitis, is able to improve several indices of liver damage, without producing any toxic adverse effects.

The effects of sumatriptan on pituitary secretion in man

Sumatriptan, a new antimigraine drug with high affinity and selectivity for certain 5-hydroxytryptamine (5-HT1D) receptor subtypes, was administered to 12 normal subjects, in order to investigate the effects of 5-HT receptor activation on anterior pituitary secretion. Sumatriptan increased plasma growth hormone (GH) levels from 2.5 +/- 0.5 mIU/l in basal conditions to 17.3 +/- 2.6 mIU/l 30 min after administration of the drug. After pre-treatment with cyproheptadine, an anti-serotoninergic drug known to inhibit GH secretion, the mean integrated sumatriptan-induced GH response decreased from 14.8 +/- 3.9 muI/l*hr to 3.7 +/- 1.7 mIU/l*hr. Sumatriptan administration did not have any effect on the secretion of the other anterior pituitary hormones. It is concluded that sumatriptan selectively increases GH secretion in man, but the exact nature of the receptors involved is not yet known.

Plasma beta‐endorphin concentrations during suckling in lactating women

Summary. Beta‐endorphin appears to be involved in the hormonal response to suckling in some animals. The peripheral secretory patterns of β‐endorphin, prolactin and cortisol were investigated in serial venous blood samples taken during suckling from eight healthy women who were breast‐feeding on the third or fourth day of the puerperium. Plasma levels of prolactin and β‐endorphin increased significantly during suckling reaching a peak after 20 min, levels of cortisol remained unaffected. It is suggested that the increased β‐endorphin derives from an extra‐hypophyseal source.

Diurnal beta-endorphin changes in human cerebrospinal fluid

Plasma and cerebrospinal fluid (CSF) beta-endorphin levels were determined by a RIA method in seven hydrocephalic male patients. The samples were simultaneously collected every two hours from 8 AM to 12 midnight and every hour from 1 AM to 7 AM. In both plasma and CSF beta-endorphin levels showed significant time-related variations during the 24 hour period. These results suggest the existence of diurnal CSF beta-endorphin variations analogous to those observed in plasma.

Plasma beta-endorphin, ACTH and cortisol secretion in man after nasal spray administration of calcitonin

SummaryBeta-endorphin, ACTH and cortisol secretion were measured in twelve healthy adult males after nasal spray administration 200 IU salmon calcitonin.A significant increase in plasma beta-endorphin, from 19.2 ng/l under basal conditions to a peak of 27.1 ng/l at 30 min was recorded. Plasma ACTH and cortisol were not affected. In individual subjects the beta-endorphin level was increased in eight of the twelve, ACTH rose in three and cortisol did not change in any of them. The data indicate that calcitonin induced a beta-endorphin increase independent of enhanced corticotrophin-cortisol release.

Comparison of Pituitary Responses to Physical Exercise in Athletes and Sedentary Subjects

Serum growth hormone (GH), prolactin (PRL), cortisol, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and thyroid-stimulating hormone (TSH) levels were evaluated before and after a bicycle ergometer exercise test in 8 male competitive volleyball players and in 8 sedentary healthy males of the same age. Increased serum GH and cortisol values after exercise in both groups were found, whereas an exercise-induced PRL release was observed in athletes only. Serum levels of LH, FSH and TSH were unaffected by the test in all subjects. A possible role of training in conditioning the hypothalamopituitary exercise-induced secretion is suggested.

Endocrine abnormalities and outcome of ischaemic stroke

Multiple endocrine abnormalities have been reported in stroke patients. In the past few years, it has been claimed that some of these abnormalities may play a role in worsening the neurological deficit and the outcome of stroke. Several mechanisms have been hypothesised, including a direct effect on the development of neuronal cell death, vasospasm, and development of brain edema. In this brief review, we discuss the current knowledge concerning the role of endothelin-1, arginine vasopressin, and cortisol in the pathogenesis of stroke. Finally, we discuss the possibility that leptin, the OB gene product, may be the link of some of these endocrine abnormalities, and that its abnormal secretion during stroke may contribute to the eating disorders and poor nutritional status often seen in these patients.

Twenty-four-hour variation in serum leptin in the elderly

To investigate the possibility that the aging process may affect the diurnal variation in serum leptin in humans, serum leptin levels were measured by a sensitive radioimmunoassay method in 12 elderly (aged 72 to 87 years) and 10 middle-aged (35 to 50 years) lean male subjects. Fasting blood samples (4 mL) were drawn at 8:00 AM, and then every 4 hours until 10:00 PM and every 2 hours from 12:00 midnight to 8:00 AM of the next morning. Circadian rhythmicity analysis was performed using the cosinor method. In elderly subjects, serum leptin levels showed a significant diurnal rhythm, which was similar to that observed in controls. Single cosinor analysis showed a significant rhythm in eight of 12 elderly subjects and in all middle-aged subjects but one. Compared with middle-aged subjects, similar mesor mean values (7.8 +/- 1.0 v 8.1 +/- 0.8 ng/mL) but a decreased amplitude (1.4 +/- 0.3 v 2.3 +/- 0.2 ng/mL) and an earlier acrophase (11:56 PM v 2:04 AM) were observed in the elderly. The data demonstrate that the diurnal variation in serum leptin is generally preserved in the elderly. However, the amplitude of leptin diurnal excursion undergoes a reduction with advancing age. It can be speculated that the blunted diurnal variation in serum leptin observed in the elderly may result in an alteration of the afferent signal in the adipose tissue-central nervous system homeostatic loop.