Wolfgang Marktl

Impaired circadian rhythm of melatonin secretion in sedated critically ill patients with severe sepsis.

OBJECTIVE Melatonin is involved in the regulation of the sleep-wake cycle and exhibits multiple interactions with the neuroendocrine and the immune system. Melatonin secretion in healthy individuals follows a stable circadian rhythm. Critical illness, continuous administration of drugs, and loss of external zeitgeber might impair the circadian rhythm of melatonin secretion in the intensive care unit (ICU), thereby compromising the physiologic stress-induced immune response. DESIGN Prospective, controlled clinical study. SETTING Medical intensive care unit in a university hospital. PATIENTS Seventeen septic, sedated ICU patients (group A); 7 nonseptic ICU patients (group B); and 21 control patients (group C) were studied. MEASUREMENTS AND MAIN RESULTS 6-Sulfatoxymelatonin (aMT6s) was determined from urine samples taken at 4-hr intervals over a total period of 24 hrs. aMT6s was measured by enzyme-linked immunosorbent assay. Circadian mesors, phase amplitudes, and timing of the acrophase were assessed by cosinor analysis. Differences between groups were calculated by contingency data analysis and by analysis of variance. Circadian mesors of urinary aMT6s were 3904 +/- 1597, 2622 +/- 927, and 3183 +/- 1514 ng/4 hrs in groups A, B, and C, respectively (p = NS). aMT6s exhibited significant circadian periodicity in only 1/17 (6%) patients of group A but in 6/7 (86%) patients of group B and in 18/23 (78%) patients of group C (group A vs. groups B and C: p = .0001) Phase amplitudes were markedly lower in group A (1071 +/- 1005 ng/4 hrs) compared with group B (2284 +/- 581 ng/4 hrs, p = .009) and C (2838 +/- 2255 ng/4 hrs, p = .006). The acrophase was significantly delayed in patients of group A (10:35 am +/- 255 mins) compared with group B (05:43 am +/- 114 mins, p = .01) and group C (4:20 am +/- 107 mins, p < .0001). In sepsis survivors, aMT6s excretion profiles tended to normalize, but still lacked a significant circadian rhythm at ICU discharge. CONCLUSION The present study revealed striking abnormalities in urinary aMT6s excretion in septic ICU patients. In contrast, circadian rhythm was preserved in nonseptic ICU patients, indicating that impaired circadian melatonin secretion in septic patients is mainly related to the presence of severe sepsis and/or concomitant medication. Further investigations are required to examine the underlying pathophysiologic mechanism and the clinical implications of this finding.

Concentrations of Seven Trace Elements in Different Hematological Matrices in Patients with Type 2 Diabetes as Compared to Healthy Controls

This study aimed to compare the trace element status of patients with type 2 diabetes (n=53) with those of nondiabetic healthy controls (n=50). The concentrations of seven trace elements were determined in the whole blood, blood plasma, erythrocytes, and lymphocytes of the study subjects. Vanadium and iron levels in lymphocytes were significantly higher in diabetic patients as compared to controls (p<0.05 for iron and p<0.01 for vanadium). In contrast, lower manganese (p<0.01) and selenium (p<0.01) concentrations were detected in lymphocytes derived from patients with type 2 diabetes versus healthy subjects. Furthermore, significantly lower chromium levels (p<0.05) were found in the plasma of diabetic individuals as compared to controls. Trace element concentrations were not dependent on the degree of glucose control as determined by correlation analysis between HBA1c versus metal levels in the four blood fractions. In summary, this study primarily demonstrated that trace element levels in lymphocytes of patients with type 2 diabetes could deviate significantly from controls, whereas, in general, no considerable differences could be found when comparing the other fractions between both patient groups. Therefore, it seems reasonable to analyze metal levels in leukocytes to determine trace element status in patients with type 2 diabetes and perhaps in other diseases.

The melatonin receptor subtype MT2 is present in the human cardiovascular system

Abstract: We showed that the melatonin receptor subtype, MT1, is expressed in healthy and diseased human coronary arteries. As studies in experimental animals suggest that the MT2 melatonin receptor subtype is also present in the vasculature, we investigated whether the MT2 is expressed in human aorta and coronary arteries. Additionally, MT2 expression in human ventricular specimens was analysed, as melatonin was shown to affect myocyte function. Expression of the MT2‐receptor was studied in sections of isolated coronary arteries, aorta and left ventricular specimens from healthy heart donors (control) and patients with dilated or ischemic cardiomyopathy. MT2 expression was found by reverse transcriptase (RT)‐nested‐polymerase chain reaction (PCR) in all of the specimens (aorta, left ventricle and coronary arteries) derived from controls. Also, visible evidence for receptor expression was found in 12 of 15 samples from cardiomyopathy patients and 10 of 15 of coronary heart disease patients. Additionally, the expression of MT2‐receptor between aorta, left ventricle and coronary arteries varied among the individuals, some of them showing highest expression in the aorta while in others principal expression sites were coronary arteries or left ventricles. In conclusion, the MT2‐receptor subtype is present in human arteries and left ventricles and it is suggested that in coronary heart disease MT2‐receptor expression is altered. Furthermore, there is evidence for heterogeneous MT2 expression patterns in individual patients.

Clock genes display rhythmic expression in human hearts.

Thus far, clock genes in the heart have been described only in rodents, and alterations of these genes have been associated with various myocardial malfunctions. In this study, we analyzed the expression of clock genes in human hearts. Left papillary muscles of 16 patients with coronary heart disease, 39 subjects with cardiomyopathy, and 9 healthy donors (52 males and 12 females, mean age 55.7±11.2; 16–70 yrs) were obtained during orthotopic heart transplantation. We assessed the mRNA levels of PER1, PER2, BMAL1, and CRY1 by real time PCR and analyzed their rhythmic expression by sliding means and Cosinor functions. Furthermore, we sought for differences between the three groups (by ANOVAs) for both the total 24 h period and separate time bins. All four clock genes were expressed in human hearts. The acrophases (circadian rhythm peak time) of the PER mRNAs occurred in the morning (PER1: 07:44 h [peak level 187% higher than trough, p = .008]; PER2: 09:42 h [peak 254% higher than trough, p < .0001], and BMAL1 mRNA in the evening at 21:44 h [peak 438% higher than trough; p < .0001]. No differences were found in the rhythmic patterns between the three groups. No circadian rhythm was detected in CRY1 mRNA in any group. PER1, PER2, and BMAL1 mRNAs revealed clear circadian rhythms in the human heart, with their staging being in antiphase to those in rodents. The circadian amplitudes of the mRNA clock gene levels in heart tissue are more distinct than in any other human tissue so far investigated. The acrophase of the myocardial PER mRNAs and the trough of the myocardial BMAL1 coincide to the time of day of most frequent myocardial incidents.

Prediction of survival after out-of-hospital cardiac arrest: results of a community-based study in Vienna

The objective of this study was the assessment of out-of-hospital cardiac arrest and the definition of possible predictive factors for final hospital discharge. Out of a database of 89,557 consecutive missions of the Vienna emergency medical system (EMS) during 1990, there were 623 missions due to a collapse of non-traumatic origin: in 374 cases (60.0%) the patients were declared dead without further attempts at resuscitation. The remaining 249 patients were analysed for predictive factors at site. Survival to hospital admission: 109 patients survived to hospital admission (43.7%); bystander support had a small impact (P < 0.05) on survival to hospital arrival whereas age and gender had no predictive power. Most patients with ventricular tachycardia/fibrillation (VT/VF) survived primarily (69 of 117, i.e. 59.0%). Survival to hospital discharge: 27 patients were discharged from hospital care (10.8%). ECG findings on arrival of the EMS physician at the site proved to be the only powerful predictor for survival: 24 of 117 patients with VT/VF survived compared with only one of 81 with primary asystole, two of 39 with severe bradycardia, and no patient with electromechanical dissociation.

24h variation in the expression of the mt1 melatonin receptor subtype in coronary arteries derived from patients with coronary heart disease

Previous studies presented evidence for impaired nocturnal secretion and synthesis of melatonin in patients with coronary heart disease (CHD). This study aimed to investigate whether the melatonin receptor subtype mt1 is differentially expressed in coronary arteries derived from patients with CHD (n = 9) compared to patients with dilative cardiomyopathy (CMP; n = 10) who served as controls. Expression of the mt1 receptor was studied in sections of isolated coronary arteries by a reverse transcriptase–polymerase chain reaction (RT-PCR) and a Western immunoblot technique. In addition, the data from the Western blotting of 15 patients were interpolated against the exact time of aortic clamp to study the 24h expression of the mt1 receptor. The analyses of the results from both methods indicated the presence of the mt1 receptor in all of the individuals. No statistically significant difference was observed in the receptor expression between patients with CHD and those with CMP (in arbitrary units: 3.39 ± 3.08 versus 3.91 ± 2.78). Expression of the melatonin receptor in the coronary arteries of the whole patient group presented a 24h variation, with the lowest values detectable after 02:00 up to the late morning hours and a progressive increase beginning after 13:00 until 00:00 (mesor = 3.66, amplitude = 3.23, acrophase = 20.45, P =. 0003). When studying the 24h variation in patients with CHD and CMP separately, a nearly similar circadian course was observed. In conclusion, we demonstrated for the first time a 24h variation of a melatonin receptor subtype in human vessels. Furthermore, in relation to our results, we suggest that the expression of the mt1 melatonin receptor in the coronary arteries is probably not impaired in patients with CHD. (Chronobiology International, 18(6), 973–985, 2001)

EXPRESSION OF THE MT1 MELATONIN RECEPTOR SUBTYPE IN HUMAN CORONARY ARTERIES

Previous experimental data suggest a possible influence of melatonin on the circulatory system of animals after binding to G-protein coupled melatonin receptors. The present study sought to investigate whether the melatonin receptor, mt1, is expressed in human coronary arteries derived from healthy heart donors (n = 8). Expression of the mt1-receptor was studied in sections of isolated coronary arteries by a reverse transcriptase-polymerase chain reaction (RT-PCR) and Western immunoblot technique. The analyses of the results from both methods indicated the presence of the mt1-receptor in all of the subjects. Referring to these data we assume that melatonin regulates physiological processes in human coronary arteries after receptor binding.

Combined inpatient rehabilitation and spa therapy for breast cancer patients: effects on quality of life and CA 15-3.

The present study investigated the changes of quality of life, mood, and the tumor marker CA 15-3 associated with a 3-week inpatient breast cancer rehabilitation program incorporating spa therapy. One hundred forty-nine women, 32 to 82 years, participated in the study 3 to 72 months after breast cancer surgery. Quality of life (QoL, EORTC QLQ-C30), anxiety, and depression (HADS) were measured 2 weeks before, at the end, and 6 months after rehabilitation; CA 15-3 at the beginning, end, and at 6 months follow-up. Patients received an individualized rehabilitation program incorporating manual lymph drainage, exercise therapy, massages, psychological counseling, relaxation training, carbon dioxide baths, and mud packs. Quality of life and mood improved significantly, the greatest short-term improvements found for mood-related aspects of quality of life, the most lasting improvements found for physical complaints (eg, fatigue). Also, the tumor marker CA 15-3 declined significantly to follow-up. Patient characteristics, as well as the time since surgery, moderated rehabilitation outcome to a limited extent. Older patients, nonobese patients, patients with a greater lymphedema, and patients with an active coping style showed slightly greater improvements. Hot mud packs inducing hyperthermia did not affect CA 15-3. In conclusion, the combination of inpatient rehabilitation with spa therapy provides a promising approach for breast cancer rehabilitation.

The melatonin receptor subtype MT1 is expressed in human gallbladder epithelia

Abstract: Based on the fact that human bile and, particularly gallbladder bile, contains high physiological levels of the antioxidant melatonin, the aim of this study was to investigate whether the melatonin receptor MT1 is present in human gallbladder. Expression and localization of MT1 was assessed by RT‐PCR, Western blotting and immunofluorescence analysis in gallbladder samples from patients with cholelithiasis and with advanced gallbladder carcinoma. Additionally, we monitored mRNA expression of the two key enzymes of melatonin synthesis, i.e. arylalkylamine‐N‐acetyltransferase (AANAT) and hydroxyindole‐O‐methyltransferase (HIOMT). MT1 mRNA and protein were present in all cholelithiasis (n = 10) and gallbladder carcinoma (n = 5) samples. As indicated from RT‐PCR and Western blot studies, MT1 is located in gallbladder epithelia. Epithelial expression was further proven by immunofluorescence staining of MT1 in paraffin‐embedded cholelithiasis and gallbladder carcinoma sections. Analysis of AANAT and HIOMT mRNA expression showed that HIOMT mRNA is present in gallbladder. Surprisingly, AANAT was not detectable under conditions where it was found in a human colon specimen. The absence of AANAT suggests that in human gallbladder, HIOMT might be involved in the formation of 5‐hydroxytryptamine products other than melatonin. In summary, our results provide the first evidence for the presence of MT1 in human gallbladder epithelia. Therefore, in addition to its profound antioxidative effects in the biliary system, melatonin might also act through MT1‐mediated signal transduction pathways. Thereby, it might be involved in the regulation of gallbladder function.

Effect of Sulfur Baths on Antioxidative Defense Systems, Peroxide Concentrations and Lipid Levels in Patients with Degenerative Osteoarthritis

Background: Due to possible antiinflammatory effects, sulfur baths are widely used for the treatment of rheumatic diseases. Previously it was demonstrated that drinking cures with sulfur can improve the antioxidative defense system and lower the peroxide levels of patients with chronic degenerative osteoarthritis. Objective: This study therefore sought to investigate the effect of 3-week therapy with sulfur baths on antioxidative defense systems, peroxide concentrations, and lipid levels in patients with degenerative osteoarthritis. Patients and Methods: After randomization one group of patients (n = 19) received sulfur baths during their stay at a health resort (sulfur group), whereas the other age-matched patient group served as controls (n = 19, control group), only receiving spa therapy. Total cholesterol levels, HDL, LDL, triglycerides and the antioxidative status, glutathione peroxidase, and superoxide dismutase (SOD) activities, and peroxide concentration, as an oxidative stress parameter, were evaluated at the begin and end of therapy. Results: A 17.2% decline in peroxide concentrations (p = 0.10, n.s.) and significant lower SOD activities (p < 0.001) were detected in the sulfur group at the end of the therapy. Until the end of therapy total cholesterol levels changed differentially (p = 0.007) in the sulfur group (from 229.11 ± 34.47 mg/dl to 217.46 ± 40.45 mg/dl) and in the control group (from 197.63 ± 34.66 mg/dl to 207.95 ± 33.02 mg/dl). A similar significant group difference was found for LDL (p = 0.017), with a 5.9% reduction in the sulfur group and a 6.1% increase in the control group. Triglyceride concentrations were nonsignificantly reduced in both groups after 3 weeks at the health resort (sulfur group 11.2%, control group 20.2%). HDL values only minimally changed in both groups. Conclusions: The results presented here suggest that a sulfur bath therapy could cause a reduction in oxidative stress, alterations of SOD activities, and a tendency towards improvement of lipid levels.