Diurnal rhythm of serum melatonin, ACTH and cortisol in asthma patients with long term glucocorticoid treatment

Forty one patients (21 women and 20 men aged 35 to 45 years), with bronchial asthma were divided into two groups: those treated with glucocorticoids (with an equivalent daily dose of 8 mg prednisone) and those receiving no glucocorticoid preparations. The control group consisted of 27 healthy volunteers. The diurnal rhythm of serum melatonin, ACTH and cortisol was evaluated in all subjects. It was found that the dysfunction and reduced reactivity of the pituitary-adrenal axis in asthmatics receiving chronic glucocorticotherapy was accompanied by suppressed melatonin rhythm.     

Age-related modifications of circadian rhythm of serum leptin in healthy men

BACKGROUND: Leptin, the product of the ob gene, is secreted by the adipocyte and is involved in the regulation of body weight, energy homeostasis and a wide spectrum of biological activities. OBJECTIVE: We studied how variations in circadian serum leptin levels change as people age. METHODS: Serum leptin levels were studied on a circadian basis in 26 men, 6 overweight (BMI >27.8) and 20 with normal weight. The normal-weight men were divided into four age groups: (A) in their 30s, (B) in their 40s, (C) in their 50s, and (D) in their 60s. Serum samples were drawn at 2-hour intervals from 8:00 to 22:00 and hourly from 22:00 to 8:00 for a total of 24 h. RESULTS: A significant circadian variation of leptin levels was found whatever the age with a peak at night and a trough around noon. The circadian leptin levels were higher in the older normal-weight groups (50s and 60s) and in the groups with a BMI >27.8. CONCLUSION: Our study demonstrates that changes in the characteristics of the circadian rhythm of serum leptin in healthy men are associated with both advancing age and increased BMI.     

Diurnal rhythm of the adrenal cortex function in patients with circulatory disorders

The blood hydrocortisone and corticosterone content and the aldosterone level in the urine were determined for 24 hours in patients with congenital heart disease before and after operative treatment. In patients with symptoms of cardiac insufficiency both glucocorticoid and mineralocorticoid activity of the adrenal cortex was marked by deviations from the diurnal physiological rhythm. This is reflected in the continuous activation of the adrenal cortex during 24 hours; activation of mineralocorticoid function in the evening and during the night is a particularly characteristic phenomenon.     

甲状腺功能紊乱患者血清瘦素水平分析

目的　探讨甲状腺功能紊乱患者血清瘦素水平变化及瘦素与垂体—甲状腺轴 (PTA)的关系。方法　对 40例Graves病 (GD)、30例甲状腺机能减退症 (甲减 )患者和 2 8名健康受试者的血清瘦素 (leptin)、游离三碘甲状腺原氨酸 (FT3 )、游离甲状腺素 (FT4 )、促甲状腺激素 (TSH)、体脂百分含量 ( %BF)进行检测 ,所有受检者体重指数 (BMI) <2 5kg/m2 。结果　对照组血清瘦素浓度为 ( 5 .38± 3.11)ng/ml ,GD组为 ( 6 .0 7± 2 .93)ng/ml ,两组比较 ,差异无显著性 ,甲减组为 ( 10 .41± 4.45 )ng/ml,与对照组比较显著升高。三组血清瘦素浓度均与其 %BF显著正相关。对照组瘦素与TSH正相关 ,与FT3 、FT4 无相关关系。GD组瘦素与TSH、FT3 、FT4 无相关关系。甲减组因大多数TSH值增高超出检测范围 ,未作瘦素与之的相关性比较 ,而瘦素与FT3 、FT4 呈负相关关系。结论　甲状腺激素可能通过影响体脂含量而调节瘦素水平 ,瘦素和PTA是共同维持机体能量稳态的两个相互关联的系统。     

胃癌患者血清leptin检测的临床意义

目的探讨胃癌患者总胆固醇（TC）、甘油三酯（TG）和瘦素（1eptin）的变化及其意义。方法分为胃癌组（94例）、胃癌术后组（86例）及正常对照组（150例）三组,检测血清Tc、TG及leptin含量。结果胃癌组及胃癌术后组血清TC及leptin含量高于正常对照组,胃癌术后组血清TC及leptin均较胃癌组降低（P均〈0．05）。结论leptin可能参与胃癌的发生发展,其作用机制与促进胃癌组织中新生血管的形成有关。     

Constitutive heterochromatin studies in patients with solid tumors

Constitutive heterochromatin of chromosomes 1, 9, and 16 was studied in 101 patients with solid tumors and 85 controls. Lymphocyte cultures were used for performing C-banded chromosome preparations. Two homologous chromosomes were regarded as heteromorphic when there was a 25% difference between their C-band size or when they fell into different classes according to the method of Patil and Lubs (1977). A statistically significant difference between patients and controls was found in chromosome 1 heteromorphism. No statistical difference between patients and controls was found in the heteromorphism of chromosomes 9 and 16. The frequencies with which pericentric inversions of the heterochromatin in chromosomes 1 and 9 occurred in cancer patients were 9.9% and 12.9%, respectively. Patients displaying this type of polymorphism usually showed an increased rate of chromosome associations. The most frequent associations were found between heterochromatic regions of chromosomes 1 and 9 and between the chromosome 9 heterochromatin and D acrocentrics. These results support the hypothesis concerning the involvement of constitutive heterochromatin of chromosome 1 in malignant disease.     

Diurnal rhythm of cerebrospinal fluid and plasma leptin levels related to feeding in non-lactating and lactating rats

Leptin suppresses food intake and increases energy expenditure in the hypothalamus. Rats consume most of their daily food intake during the dark phase of the diurnal cycle. Lactating rats have increased food intake, but the involvement of leptin in the regulation of food intake in this physiological condition is not well understood. The present experiment was carried out to determine the circadian pattern of leptin concentrations in plasma and cerebrospinal fluid (CSF) in relation to the feeding behavior of non-lactating and lactating rats.Female rats were maintained on a controlled lighting schedule (lights on between 0600 and 1800 h) and the food intake of lactating rats was two- or threefold higher than that of non-lactating rats. In both groups, food intake was three times greater in the dark phase (P<0.01) compared with the light phase. The plasma concentrations of leptin were lower (P<0.01) in lactating rats than non-lactating rats in both light and dark phases, but there were no differences in plasma leptin levels between light and dark phases. In contrast, and in both groups, the leptin concentrations in CSF were lower (P<0.01) in the dark phase than in the light phase. Leptin levels in CSF were lower (P<0.01) in lactating rats than in non-lactating rats. We conclude that a diurnal pattern of leptin levels within the brain (but not in plasma) reflects characteristics of feeding behavior in lactating and non-lactating rats.     

A decreased serum leptin level in patients with systemic sclerosis

Serum leptin levels were determined in 31 women with systemic sclerosis and 24 age-matched healthy controls. Both groups were divided into premenopausal and postmenopausal subgroups. A decreased serum leptin was found in the patients with systemic sclerosis. The premenopausal patients and controls had higher serum leptin than those in the postmenopausal subgroups. Serum leptin correlated with body mass index in the patients with systemic sclerosis. Received: 2 June 2000 / Accepted: 15 March 2001     

Adiponectin and leptin serum concentrations in patients with rheumatoid arthritis

Adipose tissue is regarded as an active metabolic and endocrine organ producing adipokines. The purpose of the study was to evaluate adiponectin and leptin concentrations in rheumatoid arthritis (RA) patients (pts) in relation to disease duration and activity. The study group consisted of 80 RA pts. Serum adiponectin and leptin concentrations remained within normal ranges. Adiponectin concentration correlated positively both with the age and disease duration. Both adipokines levels correlated negatively with glomerular filtration rate. There were significant positive correlations between adipokines’ concentrations and lipid profile components (between adiponectin and HDL-cholesterol, leptin and total cholesterol and LDL-cholesterol). In pts with long-standing RA, there was a negative correlation between adiponectin and numbers of tender, swollen joints and a positive relationship between leptin level and DAS28. The results confirm adipokines’ involvement in the process of inflammation and atherosclerosis: protective and antiinflammatory adiponectin effect and proatherogenic and proinflammatory leptin function.     

Diurnal and ultradian dynamics of serum adiponectin in healthy men: comparison with leptin,circulating soluble leptin receptor,and cortisol patterns

Adiponectin is an abundant serum adipokine secreted exclusively from differentiated adipocytes, which plays an important role in regulating insulin sensitivity. The dynamics of circulating adiponectin concentrations have yet to be systematically investigated. We sought to determine whether serum adiponectin levels exhibit diurnal or ultradian rhythms in healthy normal-weight men and to compare the 24-h profile of adiponectin fluctuations with those of leptin, leptin-binding protein (sOB-R), and cortisol. We collected blood samples at 15-min intervals over 24 h from six subjects receiving an isocaloric diet, and we measured adiponectin, leptin, sOB-R, and cortisol levels. Fourier and cross-correlation analyses were performed on these time series to study diurnal variations, and the Cluster7 program was used for pulsatility analysis. Circulating adiponectin and sOB-R levels exhibited ultradian pulsatility as well as a diurnal variation with a significant decline at night, reaching a nadir in the early morning. The 24-h variations of serum adiponectin and sOB-R were nearly identical and followed those of cortisol after a few hours, but were out-of-phase with leptin diurnal rhythms. These data suggest that adiponectin and sOB-R levels might be influenced by common regulatory factors and challenge the notion that cortisol may have a direct inhibitory effect on adiponectin in humans.     

功能性消化不良患者血清Ghrelin及瘦素水平变化

目的 探讨功能性消化不良(FD)患者血清Ghrelin及瘦素水平变化及其临床意义.方法 60例FD患者,其中餐后不适综合征(PDS)30例,上腹痛综合征(EPS)30例,健康对照者30名,分别采用酶联免疫法和放射免疫法检测血清Ghrelin及瘦素水平.结果 FD组血清Ghrelin水平较对照组明显减低(P<0.01);FD组血清瘦素水平也较对照组明显减低(P<0.05);PDS组血清Ghrelin和瘦素水平较对照组明显减低(P<0.01),且较EPS组明显减低(P<0.01);而EPS组血清Ghrelin和瘦素水平与对照组比较,差异无统计学意义(P>0.05).结论 FD患者血清Ghrelin和瘦素水平减低主要是由PDS患者血清水平改变所致.PDS的病理机制可能主要与胃肠运动异常相关;血清Ghrelin和瘦素在FD发病过程中存在相互作用,对其的检测可能有助于FD分型和指导治疗.     

Elevated serum levels of leptin and soluble leptin receptor in patients with advanced chronic heart failure

Patients with chronic heart failure (CHF) have metabolic abnormalities, leading to a catabolic syndrome, with progressive loss of skeletal muscle in advanced stages of the disease. Leptin, the product of an obesity gene, has been associated with energy expenditure and weight regulation. The aim of this study was to assess serum levels of leptin and its soluble receptor in relation to exercise intolerance and neurohumoral activation in patients with CHF. We investigated 53 patients with CHF left ventricular ejection fraction (LVEF) 25+/-1%, age 56.6+/-1.3 years, Maximal oxygen uptake (VO(2) max) 16.3+/-0.6 ml/min.kg) sub-classified according to peak oxygen consumption of > or 14 ml/min.kg and controls). Elevated levels of leptin correlated with an increased serum concentration of TNFalpha (r=0.749, P<0.01) in this subgroup of patients with CHF. We conclude that patients with advanced CHF show elevated serum levels of leptin and its soluble receptor. This finding indicates that leptin may participate in the catabolic state leading to the development of cardiac cachexia in the course of CHF.     

阻塞性睡眠呼吸暂停患者血清瘦素水平的研究

目的　探讨瘦素在阻塞性睡眠呼吸暂停综合征 (OSAS)患者体内的变化。方法　选择年龄及体重指数 (BMI)差异无显著性的OSAS患者 5 8例和单纯肥胖者 2 1例 ,用多导睡眠呼吸监测仪进行监测 ,用放射免疫法测定所有对象的血清瘦素。结果　 (1)无论男性还是女性 ,OSAS患者瘦素水平 [(6 1± 1 7) μg/L ,(19 5± 9 9) μg/L]平均高于单纯肥胖者 [(4 5± 1 7) μg/L ,(10 5± 2 4) μg/L](P <0 0 1,P <0 0 5 )。 (2 )单纯肥胖者及OSAS患者血清瘦素水平分别与BMI呈显著正相关 (r=0 5 9,P <0 0 1;r=0 6 4,P <0 0 1) ,同时OSAS患者血清瘦素水平分别与呼吸暂停及低通气指数 (AHI) (r=0 47,P <0 0 1)和颈围 (r=0 6 4,P <0 0 1)也有明显的正相关。结论　OSAS患者血清瘦素水平比单纯肥胖者更高 ,除了肥胖、颈围宽外 ,OSAS本身也是引起瘦素水平升高的原因。