Jacek Swietoslawski

Chronic exposure to 2.9 mT, 40 Hz magnetic field reduces melatonin concentrations in humans

Karasek M, Woldanska‐Okonska M, Czernicki J, Zylinska K, Swietoslawski J. Chronic exposure to 2.9 mT, 40 Hz magnetic field reduces melatonin concentrations in humans. J. Pineal Res. 1998; 25:240–244.

Systemic blood osteopontin, endostatin, and E-selectin concentrations after vertical banding surgery in severely obese adults.

BACKGROUND Obesity is associated with endothelial dysfunction and increased inflammation as well as with expansion of the capillary bed in regional adipose deposits, and a balance between these factors is involved in angiogenesis. Osteopontin (OPN) is a proinflammatory cytokine involved in regulating immune processes and mediating chronic inflammation. Its level is usually elevated in the plasma and adipose tissue of obese subjects. E-selectin, an adhesion molecule which is released by dysfunctional endothelial cells, is believed to be a marker of an early atherosclerotic process. Endostatin (END), an angiogenesis inhibitor, is present in the blood of obese subjects. The most effective treatment to achieve weight loss in morbidly obese subjects is bariatric surgery. The aim of the study was to evaluate and compare the circulating concentrations of OPN, E-selectin and END as well as the insulin resistance (HOMA-IR) of severely obese patients with metabolic syndrome before and after vertical banded gastroplasty (VBG). MATERIAL AND METHODS The test cohorts comprised eight males and 20 females (total 28 patients) aged from 20 to 59 years with simple obesity and the presence of metabolic syndrome, both before and 3, 6, 12, 24 months after bariatric surgery (six patients were also checked after 36 and four after 48 months). RESULTS Bariatric surgery significantly reduced (over 24 months) body weight, BMI, waist circumference, HOMA-IR and blood concentrations of CRP. Plasma OPN gradually increased after VBG and E-selectin in systemic blood decreased. We did not observe any differences in END concentrations from 12 to 48 months after surgery. CONCLUSION VBG improves metabolic syndrome parameters, decreases E-selectin and gradually increases OST blood concentrations but it does not have any significant influence on END levels.

Serum melatonin circadian profiles in women suffering from cervical cancer

Abstract:  Although there is an increasing evidence that the pineal gland may play a role in human malignancy, the studies on melatonin concentrations in different types of malignant tumors brought about controversial results. However, changes in melatonin concentrations have been observed in some types of human malignant tumors. Therefore, we decided to study the circadian melatonin rhythm in patients suffering from cervical cancer in different stages of progression and to compare them with those in subjects free from neoplastic disease. A total of 45 women were analyzed in this study. The subjects were divided into two groups. The first group consisted of 31 patients [mean age 52.1 ± 1.8 yr (mean ± S.E.M.), range 32–77 yr] with cervical cancer in various stages of the disease. The second group consisted of 14 healthy volunteers [mean age 53.5 ± 2.0 yr (mean ± S.E.M.), range 42–63] who served as the control group. Blood samples were collected at 08:00, 12:00, 16:00, 20:00, 22:00, 24:00, 02:00, 04:00, 06:00, and 08:00 hours. Melatonin concentration was measured by immunoenzymatic method. There were significant differences in circadian melatonin profiles as well as in the area under curve among the two studied groups. Melatonin concentrations were significantly lower in cancer patients in comparison with healthy individuals. Taking into consideration stage of the cervical cancer significantly lower melatonin secretion has been found in all subgroups of patients in comparison with that of tumor‐free control group. Additionally, nocturnal melatonin concentrations as well as area under curve were significantly lower in advanced stage of cancer (stages 3 and 4) in comparison with patients with preinvasive cancer (stage 0) at 24:00, 02:00, and 04:00 hours and patients with stage 1 disease at 02:00 and 04:00 hours. The results of the present study indicate that the presence of cervical cancer influences melatonin levels in women. Moreover, stage dependence in reduction of melatonin concentrations has been found.

Chronic exposure to 25-80-μT, 200-Hz magnetic field does not influence serum melatonin concentrations in patients with low back pain

There is substantial evidence that magnetic field (MF) exposure influences melatonin secretion in animals. However, data on its influence on human melatonin levels are scarce, and seemingly contradictory. Because of its many beneficial effects, very low‐frequency MF exposure is used in physiotherapy of some neurological diseases and overloading syndromes of the locomotor system. In previous studies, we observed a decrease in human serum melatonin nocturnal concentrations after exposure to MF (2.9 mT, 40 Hz), and we suggested that differences among various studies may depend on different characteristics of the applied MF. Therefore, in the present study, we examined whether or not MF of different parameters exerts the same effect. The study was performed in seven men (mean age: 36.7±3.8 years; range: 32–42) suffering from low back pain. Patients were exposed to a pulsating MF (induction: 25–80 μT; frequency: 200 Hz, modulated, automatically programmed; complex saw‐like impulse shape; bipolar) generated by a Quatronic MRS 2000 apparatus (“magnetic bed”) for 3 wk (5 days/wk, twice a day at 08:00 and 13:00 hr for 8 min each), applied to the whole body in patients laying in a horizontal position. The study was performed in spring. Diurnal serum melatonin profiles were estimated 1 day before exposure to MF (baseline), and 1 day and 1 month after the last exposure. No changes in melatonin concentrations were observed either after 1 day or after 1 month following the exposure in comparison to baseline.

Serial Transplants of 7,12-Dimethylbenz[a]anthracene-Induced Mammary Tumors in Fischer Rats as Model System for Human Breast Cancer

The aim of the present study was to investigate the ultrastructure of pinealocytes and plasma melatonin concentrations in Fischer rats bearing an advanced (14th) passage 7,12-dimethylbenz[a]anthracene-induced mammary tumor. Quantitative ultrastructural analysis of the cell size and relative volumes of various cell organelles as well as the number of dense-core vesicles was performed in pinealocytes of the animals killed either during the daytime (15.00 h) or at night (3.00 h) 1 month after tumor transplantation. No significant differences between control and tumor-bearing animals were observed either during the daytime or at night. However, plasma melatonin concentrations in tumor-bearing rats killed at 3.00 h were suppressed by 35% (p < 0.025) when compared to the control animals killed at the same time.

Somatostatin Analogs and Tumor Localization Do Not Influence Vitamin D Concentration in Patients with Neuroendocrine Tumors

ABSTRACT Patients with neuroendocrine tumors (NETs), malignancies of rare but still rising incidence, may be a group at higher risk of vitamin D insufficiency. The gastrointestinal tumor prevalence and somatostatin analog (SSA) therapy may cause vitamin D malabsorption. The aim of this study was to evaluate the serum level of vitamin D in NET patients. A total of 36 NET patients were enrolled into the experimental group and 16 individuals were enrolled into the control group. All patients were further classified into subgroups according to primary tumor localization (gastropancreatic, lung, and other NETs) or therapy (with or without SSA treatment). The concentrations of total 25(OH)D were assayed with Electrochemiluminescence immunoassay (ECLIA). Serum concentration of 25(OH)D in NET patients did not differ significantly from that of the control group. However, the average level of 25(OH)D in both groups met the criteria of vitamin D deficiency. Importantly, SSA therapy did not aggravate vitamin D deficiency. Moreover, the concentration of 25(OH)D in the studied group was not significantly influenced by primary tumor localization, patient age, or season. Vitamin D deficiency is a widespread disorder affecting both NET patients and individuals without other health problems, and SSA and gastrointestinal tumor localization do not exacerbate this condition.

Expression of follicle stimulating hormone receptors in pituitary adenomas — a marker of tumour aggressiveness?

INTRODUCTION In our earlier study, we found that pituitary adenomas, like other human tumours, express ectopically follicle stimulating hormone receptors (FSHR) in intratumoural blood vessels endothelia and/or tumoural cells. The aim of the present paper was to provide more detailed data on FSHR expression in different subtypes of pituitary adenomas and to evaluate its possible role as a prognostic and/ or predictive biomarker in these tumours. MATERIAL AND METHODS Forty two pituitary adenomas, surgically removed, were immunostained with antibodies against the pituitary hormones, antigen Ki-67 and 1-190 fragment of FSHR. RESULTS The positive FSHR immunostaining was found in blood vessels endothelia of 88% of adenomas and in tumoural cells of 40% adenomas. In tumoural cells, the incidence of at least moderate FSHR immunostaining is significantly higher in invasive tumours (68%) compared to non-invasive (12%) ones, and higher (albeit not statistically significantly) in invasive-proliferating adenomas (Ki-67 > 3%, grade 2b) compared to invasive but non-proliferating (Ki-67 < 3%, grade 2a) ones. CONCLUSIONS The present study confirms that pituitary adenomas ectopically express FSHR in intratumoural blood vessels endothelia and tumoural cells. Moreover, the expression in tumoural cells is prevalent in invasive and proliferating adenomas vs. non-invasive and non-proliferating tumours.

INFLUENCE OF LOW-FREQUENCY MAGNETIC FIELD OF DIFFERENT CHARACTERISTICS ON SERUM MELATONIN CONCENTRATIONS IN HUMANS

There is substantial evidence that magnetic field (MF) influences melatonin secretion in animals (see 5). However, data on its influence on human melatonin levels are scarce, and contradictory (3,4,6–8). On the other hand, because of its many beneficial effects, such as anti-inflammatory and analgesic action, improvement of soft tissue regeneration processes, vasodilatory action or oxygen utilization and tissue respiration, very low-frequency MF is used in physiotherapy of some neurological diseases and overloading syndromes of locomotor system ( 1,2). Since the data on the influence on melatonin levels, both in humans and animals are inconsistent, and in our previous studies (6) we suggested that differences among various studies may depend on different characteristics of applied MF, we decided to compare the effects of MF of different parameters in subjects with low back pain syndrome before and after chronic exposure to low-frequency MF generated by two different apparatuses used in standard physiotherapy.