Autonomic Nervous System Function in Newly Diagnosed Multiple Sclerosis: Association With Lipid Levels and Insulin Resistance.

Autonomic nervous system (ANS) disorders are common in multiple sclerosis (MS). Previous studies showed differences in insulin resistance (IR) and lipoprotein levels in MS subjects compared to controls. Lipolysis caused by increased sympathetic activity could be one of the possible linking mechanisms leading to dyslipidemia in MS. Our study aimed to evaluate ANS activity in the context of glucose and lipid metabolism in people with MS. We prospectively measured short-term heart rate variability (HRV), fasting lipoprotein concentrations, and calculated IR indices based on plasma glucose and insulin levels during oral glucose tolerance test (oGTT) in 32 patients with MS and 29 healthy controls matched for age, sex and body mass index in our study. There was no significant difference in HRV parameters and lipoprotein levels between MS and controls. A significant positive correlation was found between low/high-frequency power ratio (LF/HF) and triglycerides (r=0.413, p=0.021) in MS subjects but not in controls. A significantly lower whole-body insulin sensitivity index (ISIMat) was found in patients with MS compared to the control group (7.3±3.7 vs. 9.8±5.6, p=0.041). No significant correlations were found between LF/HF and IR parameters. In MS subjects, the positive correlation of LF/HF with triglycerides could reflect the effects of sympathetic activity on lipolysis. Positive correlations of sympathetic activity with increased lipoprotein levels could rather reflect processes associated with immune system activation/inflammation, than processes involved in glucose homeostasis maintenance.

Nutritional intervention as an essential part of multiple sclerosis treatment?

Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system. In addition to the genetic, epigenetic and immunological components, various other factors, e.g. unhealthy dietary habits, play a role in the MS pathogenesis. Dietary intervention is a highly appealing approach, as it presents a simple and relatively low risk method to potentially improve outcomes in patients with brain disorders in order to achieve remission and improvement of clinical status, well-being and life expectancy of patients with MS. The importance of saturated fat intake restriction for the clinical status improvement of MS patients was pointed for the first time in 1950s. Recently, decreased risk of first clinical diagnosis of CNS demyelination associated with higher intake of omega-3 polyunsaturated fatty acids particularly originating from fish was reported. Only few clinical trials have been performed to address the question of the role of dietary intervention, such is e.g. low saturated fat diet in MS treatment. This review summarizes current knowledge about the effect of different dietary approaches (diets low in saturated fat and dietary supplements such as fish oil, lipoic acid, omega-3 polyunsaturated fatty acids, seeds oils, high fiber diet, vitamin D, etc.) on neurological signs, patient's well-being, physical and inflammatory status. So far the results are not conclusive, therefore much more research is needed to confirm and to understand the effectiveness of these dietary interventions in the long term and well defined studies.

Obesogenic and diabetogenic impact of high organochlorine levels (HCB, p,p'-DDE, PCBs) on inhabitants in the highly polluted Eastern Slovakia.

OBJECTIVE: This study was aimed to evaluate possible obesogenic and diabetogenic impact of highly increased serum level of persistent organochlorinated pollutants POPs, such as polychlorinated biphenyls (PCBs), dichlorodiethyl-dichloroethylene (p,p'-DDE), and hexachlorobenzene (HCB), on the level of obesity markers (cholesterol and triglyceride level in serum, and body mass index [BMI]) and diabetes markers (fasting glucose and fasting insulin in serum) in inhabitants of Eastern Slovakia. METHODS: In young (21-40 years) males (n=248) and females (n=330) as well as in old (41-75 years) males (n=586) and females (n=889), the serum levels of 15 polychlorinated biphenyl congeners (Σ15PCBs), p,p'-DDE and HCB, and serum insulin, testosterone, total cholesterol, triglycerides and glucose levels have been estimated by high resolution gas chromatography/mass spectrometry and by the appropriate electrochemiluminiscent immunoassay or chemical methods, respectively. RESULTS: In both age groups of males and females, the levels of Σ15PCBs, p,p'-DDE, and HCB were very high and their mutual interrelations were highly significant (p<0.01). However, it should be noted that no significant changes were found in individual variables related to very high level of Σ15PCBs, except of increased BMI (p>0.05) in females.In all ages and gender groups, defined above general as related to increasing level of individual OCPs in individual age and gender groups, significant increase in cholesterol and triglyceride levels as well as BMI values, supported their obesogenic effect, while significant increase in fasting glucose and insulin in serum, supported their diabetogenic effect. Finally, highly significant decrease in testosterone level, as found in both young and old males, supported the antiandrogenic effect, namely of HCB. However, somewhat less of p,p'-DDE, while PCBs did not show any such effect in spite of their very high level. CONCLUSIONS: Highly increased blood levels of diabetes (fasting glucose and insulin) and obesity markers (cholesterol, triglyceride and BMI) were found in large groups of males and females in highly polluted area of Slovakia. Significant decrease in testosterone level was also observed in males.

Determinants of adrenal androgen hypofunction in premenopausal females with rheumatoid arthritis.

The aim of our study was to investigate adrenocortical function in the context of disease activity and inflammatory status in premenopausal RA females. Adrenal glucocorticoid and androgen responses to the 1 microg ACTH 1-24 test were investigated in 23 premenopausal RA and in 15 age- and BMI-matched healthy females. Twelve RA patients were on low-dose prednisone (<8.5 mg/day). Patients with DAS28>3.2 had lower (p<0.05) total plasma cortisol, 17-hydroxyprogesterone, dehydroepiandrosterone and androstenedione responses in the ACTH test compared to healthy controls. Patients with DAS28>3.2 had lower (p<0.05) dehydroepiandrosterone response in the ACTH test compared to patients with DAS28

Measurement of salivary aldosterone: validation by low-dose ACTH test and gender differences.

The aim of the present study was to validate the feasibility of measurement of the salivary aldosterone concentrations by performing a low-dose adrenocorticotropic hormone (ACTH) test. Moreover, the presence of gender differences in salivary aldosterone, considering the phase of the menstrual cycle in women, was verified. The sample consisted of 107 volunteers (60 men, 21 women in the follicular phase and 26 women in the luteal phase of the menstrual cycle). Saliva samples were taken by the subjects themselves around 08:00 AM, at least 60 min after awaking. A separate group of female subjects in the follicular phase underwent low-dose ACTH test (1µg synthetic ACTH i.v.) performed at 08:30 AM with blood and saliva sampling every 30 min for 120 min. Modification of the commercial aldosterone radioimmunoassay methodology for the salivary aldosterone measurement was performed. Salivary aldosterone concentrations rose in response to low-dose ACTH test and positive significant correlation in aldosterone concentrations between plasma and saliva was found. The results showed that women in the luteal phase of the menstrual cycle exhibited significantly higher morning concentrations in salivary aldosterone than men and women in the follicular phase. This study clearly demonstrates suitability of measurement of salivary aldosterone concentrations in the low-dose ACTH test and reveals gender differences in salivary aldosterone levels. The results show high validity of the presented method and its usefulness for assessment of the aldosterone concentrations in saliva.

Chronic inflammation and low-dose glucocorticoid effects on glucose metabolism in premenopausal females with rheumatoid arthritis free of conventional metabolic risk factors.

Chronic systemic inflammation is associated with increased cardiovascular mortality in patients with rheumatoid arthritis (RA). The aim of our study was to investigate association of glucose metabolism and inflammatory markers in a group of patients with rheumatoid arthritis free of other metabolic risk factors. Twenty-two premenopausal RA females (11 patients on low-dose GC (<8.5 mg/day of prednisone or equivalent), 11 patients without glucocorticoid therapy) and 15 age- and BMI-matched healthy females underwent the oral glucose tolerance test. The insulin sensitivity indices according Matsuda (ISI(MAT)) and Cederholm (ISI(CED)) as well as HOMA2 %S were calculated. Cytokines, lipid profile, non-esterified fatty acids (NEFA) and plasminogen activator inhibitor-1 (PAI-1) were measured in baseline blood samples. Despite elevated interleukin IL-6 and TNF alpha, glucose, insulin and C-peptide responses to oral glucose load as well as ISI(MAT), ISI(CED), PAI-1 and NEFA were comparable in both RA groups and healthy controls. HOMA2 %S correlated with disease activity. In conclusions, low-dose glucocorticoid treatment does not lead to glucose metabolism impairment in RA patients without other metabolic risk factors. Increased cardiovascular mortality and morbidity is probably due to a direct effect of systemic inflammation on myocardium and/or blood vessels.

Blood testosterone in middle aged males heavily exposed to endocrine disruptors is decreasing more with HCB and p,p'-DDE related to BMI and lipids, but not with Σ15PCBs.

OBJECTIVE: This work was aimed to evaluate the fundamental relations between the blood levels of testosterone (TEST) and persistent organochlorinated pollutants (POPs) related to body mass index (BMI) and blood lipids in a cohort of heavily exposed males from Eastern Slovakia. METHODS: In 429 middle aged (41-55 years) males heavily exposed to POPs the levels of 15 polychlorinated biphenyl congeners (Σ15PCBs), hexachlorobenzene (HCB), and dichlorodiethyl-dichloroethylene (p,p'-DDE) were measured by gas chromatography/mass spectrometry and the total testosterone (TEST) by electrochemiluminiscent immunoassay. RESULTS: After classifying the values of BMI, TEST, HCB, p,p'-DDE, and Σ15PCBs in quintiles and evaluating mutual interrelations of individual quintile counts in pairs of variables with chi-square, statistically significant interrelation was found for BMI/TEST (<0.0001) and HCB/TEST (p<0.001), but not for p,p'-DDE/TEST (p<0.6036) and Σ15PCBs/TEST (p<0.3246). Moreover, highly significant negative correlation was found between HCB and TEST by means of both Pearson (p<0.01) and Spearman rank correlations (p<0.0001). However, similar correlations performed between p,p'-DDE and Σ15PCBs did not reveal statistical significance. Finally, highly significant positive correlations were found between HCB and BMI, age, total lipids, and triglycerides. However, these correlations were less significant for p,p'-DDE and not significant or even negligibly negative for Σ15PCBs. In contrast, correlations of TEST with BMI and lipid fractions were significantly negative. CONCLUSION: It appears that HCB might play a role in a decrease of TEST in males with relatively narrow age range of males highly exposed to POPs. Highly significant positive correlation of HCB with BMI and blood lipids points out the role of BMI as an imaginary compartment closely related to the total body fat mass and representing a depot of POPs which is closely related to the level of POPs and lipids in blood. However, the differences in the affinity of individual POPs to BMI and blood lipids as well as the mechanism of their different relation to blood TEST levels remain to be still explained.

Alpha-fetoprotein, carcinoembryonic antigen and beta2-microglobulin in adult population highly exposed to organochlorinated pollutants (PCB, DDE and HCB).

OBJECTIVE: It is aimed to obtain some general information about the prevalence of certain biomarkers in highly exposed population and on the interrelations between their serum level as related to that of some major organochlorines (OCs). METHODS: The level of alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA) and beta2-microglobulin (beta2-MG) as well as that of polychlorinated biphenyls (Σ15PCBs), dichlorodiphenyl-dichloroethylene (DDE) and hexachlorobenzene (HCB) was estimated in 2046 adults (834 males and 1212 females) from highly polluted Eastern Slovakia. RESULTS: Great majority of blood levels was lower than two specific units used for individual markers, while the prevalence of values higher than two specific units of appropriate markers. At the same time, the prevalence of all markers level higher than 2 specific units was highly significantly increasing with of stratified PCBs level quintiles which were also positively related to these of DDE and HCB. Some significant correlations between biomarkers level and age were also observed. CONCLUSIONS: Although from the data obtained within this multipurpose field survey any notable interrelations between AFP, CEA and beta2-MG and some specific diseases and/or malignant processes could not be retrospectively specified, from the data obtained it appears that some of such interrelations cannot be definitely excluded.

Insulin resistance in young, lean male subjects with essential hypertension.

Impaired insulin action, frequently found in essential hypertension (HT), is modified by other factors, such as higher age, accumulation of body fat, dyslipidaemia, impaired glucose metabolism and endothelial dysfunction. In addition, antihypertensive and insulin-sensitizing medication itself may significantly affect cardiovascular and metabolic milieu. The aim of this study was to assess insulin sensitivity, acute insulin response, lipidaemic status and the adipokines' concentrations with regard to abdominal fat distribution in young, lean male subjects with treatment-naïve essential HT and in matched healthy normotensive (NT) subjects. We studied 27 HT patients (age: 19.9±0.6 years; body mass index (BMI): 22.9±0.5 kg m(-2)) and 15 NT controls (age: 22.3±1.0 years; BMI: 23.7±0.6 kg m(-2)). The subjects underwent an oral and an intravenous glucose tolerance test (OGTT, IVGTT) on separate days in random order. Higher fasting insulin (P<0.001), non-esterified fatty acids (P<0.05) and plasminogen activator inhibitor factor 1 concentrations (P<0.05) were found in HT patients when compared with NT patients. Despite comparable anthropometric parameters and body fat distribution assessed by magnetic resonance imaging in both groups, newly diagnosed untreated young hypertensive male subjects showed decreased insulin sensitivity, augmented insulin response to both oral and intravenous glucose load (P<0.01; P<0.05 respectively) and 'higher still normal' 2-h plasma glucose levels during OGTT. Untreated, young, lean hypertensive male subjects, with distribution of abdominal adipose tissue and lipid profile comparable with their healthy NT matched counterparts, showed considerable signs of insulin resistance and hyperinsulinaemia. We hypothesize that insulin resistance is the initial feature, which is influenced by several environmental factors, and HT is one of their common consequences.

Polychlorinated biphenyls and testosterone: age and congener related correlation approach in heavily exposed males.

OBJECTIVE: It was aimed to evaluate some fundamental correlations of 15 individual PCB congeners and their sum with serum testosterone level in highly and long-term exposed males with special respect to minimize the interfering effect of age. METHODS: A total of 834 males from eastern Slovakia (age range of 21-78 years; median, 75th and 90th percentile of 48, 54 and 58 years, respectively) were examined consisting of 432 males from highly polluted area and 402 males from the area of background pollution. In all of them the serum level of 15 polychlorinated biphenyl congeners (PCBs), hexachlorobenzene (HCB) and dichlorodiethyl-dichloroethylene (DDE) was measured by gas chomatography/mass spectrometry and total testosterone in serum was measured with the aid of electrochemiluminiscent immunoassay. Pearson's correlation coefficients for each individual PCB congener as well as for Sigma15PCBs with testosterone were assessed in the cohort of all 834 males and also in the cohort of 444 males with age range of 41-55 years in which any significant negative influence of age on testosterone level has not been found and thus the interfering effect of aging on that level was apparently minimized. RESULTS: In the cohort of 834 males with high level of Sigma15PCBs (median = 885; range = 211-77,084; 5% - 95% = 377 - 4051 ng/g lipid) and highly significant negative correlation with age (r= 0.303; p<0.000) a significant negative correlation (p<0.05) with testosterone has been observed only for two mono-ortho-congeners (CB-105 and -118). However, in the cohort of 444 males aged 41-55 years any significant correlation for individual PCB congeners and for Sigma15PCBs with testosterone did not appear. CONCLUSION: In a large cohort of highly exposed males with minimized interfering effect of age any significant correlations between 15 PCB congeners analyzed and total testosterone were not found.

High prevalence of prediabetes and diabetes in a population exposed to high levels of an organochlorine cocktail.

AIMS/HYPOTHESIS: A heavily polluted area of Eastern Slovakia was targeted by the PCBRISK cross-sectional survey to search for possible links between environmental pollution and both prediabetes and diabetes. METHODS: Associations of serum levels of five persistent organic pollutants (POPs), namely polychlorinated biphenyls (PCBs), 2,2'-bis(4-chlorophenyl)-1,1-dichloroethylene (p,p'-DDE), 2,2'-bis(4-chlorophenyl)-1,1,1-trichloro-ethane (p,p'-DDT), hexachlorobenzene (HCB) and beta-hexachlorocyclohexane (beta-HCH), with prediabetes and diabetes were investigated in 2,047 adults. Diabetes and prediabetes were diagnosed by fasting plasma glucose in all participants and by OGTT in 1,220 compliant participants. RESULTS: Our population was stratified in terms of individual POPs quintiles and associations between environmental pollution, prediabetes and diabetes were investigated. Prevalence of prediabetes and diabetes increased in a dose-dependent manner, with individuals in upper quintiles of individual POPs showing striking increases in prevalence of prediabetes as shown by OR and 95% CI for PCBs (2.74; 1.92-3.90), DDE (1.86; 1.17-2.95), DDT (2.48; 1.77-3.48), HCB (1.86; 1.7-2.95) and beta-HCH (1.97; 1.28-3.04). Interestingly, unlike PCBs, DDT and DDE, increased levels of HCB and beta-HCH seemed not to be associated with increased prevalence of diabetes. Nevertheless, individuals in the 5th quintile of the variable expressing the cumulative effect of all five POPs (sum of orders) had a more than tripled prevalence of prediabetes and more than six times higher prevalence of diabetes when compared with the 1st referent quintile. CONCLUSIONS/INTERPRETATION: Increasing serum concentrations of individual POPs considerably increased prevalence of prediabetes and diabetes in a dose-dependent manner. Interaction of industrial and agricultural pollutants in increasing prevalence of prediabetes or diabetes is likely.

[Evaluation of 11beta-hydroxysteroid dehydrogenase type 1 activity in female patients with rheumatoid arthritis]. / Hodnotenie aktivity 11beta-hydroxysteroid dehydrogenázv typu 1 u pacientiek s reumatoidnou artritídou.

INTRODUCTION: Cortisol levels in patients with rheumatoid arthritis (RA) are considered inadequate to ongoing inflammation. One possible mechanism ofthe relative cortisol deficit can be decreased 11beta-hydroxysteroid dehydrogenase type 1 (11BHSD1) activity, an enzyme that converts inactive cortisone to active cortisol. The aim of the study was to determine systemic and local activity of 11 BHSD1 in female patients with RA. METHODS: Six female RA patients without glucocorticoid therapy (age 29 +/- 2 years, BMI 21 +/- 1 kg/m2) and six healthy women (age 30 +/- 2 years, BMI 21 +/- 1 kg/m2) were studied. Endogenous cortisol production was suppressed by dexamethasone. 11BHSD1 activity was evaluated by changes in concentrations of total plasma, free plasma, salivary and cortisol in subcutaneous adipose tissue after cortisone acetate administration (25 mg per os). RESULTS: Concentrations of total plasma, free plasma, salivary, and tissue cortisol increased significantly, however there was no significant difference between RA patients and controls. CONCLUSION: The result suggests comparable systemic and adipose tissue conversion of cortisone to cortisol. Despite chronic inflammation, systemic activity of 11BHSD1 is not responsible for relative adrenal deficiency in RA. Changes in local activity of the enzyme in tissues affected by inflammatory process cannot be excluded.

Impaired insulin secretion and uptake in patients with diffuse idiopathic skeletal hyperostosis.

OBJECTIVE: So far, high prevalence of metabolic symptoms accompanying diffuse idiopathic skeletal hyperostosis (DISH) appears not definitely elucidated because of their possible origin from other disorders such as diabetes and/or body mass differences. From such reasons this study was aimed to compare non-diabetic DISH patients to a group of age and BMI matched controls in order to distinguish the influence of DISH proper on metabolic parameters free of additional metabolic effects caused by diabetes and/or body weight differences. METHODS: Both groups of patients were subjected to oral glucose tolerance test (OGTT) and fasting serum levels of glucose, insulin, C-peptide, growth hormone, insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGF-BP3) were assayed. Fasting serum total cholesterol, HDL cholesterol, triglycerides, non-esterified fatty acids (NEFA) and uric acid were determined as well. The indices of insulin sensitivity and insulin secretion were calculated. RESULTS: With the exception of decreased NEFA serum level and decreased insulinogenic index and insulin/C-peptide ratio in DISH patients any other significant differences in serum parameters and indices of insulin sensitivity were not found. CONCLUSIONS: The data obtained suggest impaired beta-cell pancreatic stimulation and increased insulin hepatic extraction in DISH. It is assumed that the above mentioned conditions, if persisting for a long time, might lead to decreased ability of insulin to maintain normal serum glucose level and consequently to insulin resistance which is highly prevalent in symptomatic DISH patients.

Increased prevalence and coincidence of antinuclear and antithyroid antibodies in the population exposed to high levels of polychlorinated pollutants cocktail.

OBJECTIVES: Because of well known association between the exposure to persistent organochlorinated pollutants (POPs) and impaired immune system, it was attempted to check possible coincidence of nuclear and thyroperoxidase antibodies with the levels of major POPs. METHODS: Antinuclear antibodies. (ANA) were estimated by indirect immunofluorescence test using Hep2- cells and thyroperoxidase antibodies (TPOab) by electrochemiluminiscent immunoassay in the cohort of 253 adults (82 males and 171 females) aged 21-75 years, among them 144 (46 males and 98 females) from the area polluted (POLL) by polychlorinated biphenyls (PCB) and 109 (36 males and 73 females) from the area of background pollutrion (BCGR). In the same cohort fifteen congeners of PCB and also total DDE (2,2'-bis(4-chlorophenyl)-1,1-dichloroethylene) and hexachlorobenzene (HCB) were estimated by high resolution gas chromatography/mass spectrometry. RESULTS: Prevalence of ANA only was significantly higher in POLL than in BCGR in males (p < 0.001) and females (p < 0.001) and the same was true for the prevalence of TPOab in males (p < 0.05) and females (p < 0.01) from POLL. In addition, also the prevalence of coincident ANA+TPOab in males (p < 0.001) and females (p < 0.05) was significantly higher in POLL. In a total of 253 pooled males and females from both areas and stratified in terms of PCB level quintiles. The prevalence of ANA in the 4th and 5th quintile of each among three pollutants (PCB, DDE and HCB) was significantly higher (p < 0.01 or < 0.001) and showed the parallel increase with the level of all pollutants. CONCLUSIONS: Significantly increased prevalence of ANA either only or in coincidence with TPOab was found related to increasing level of PCB, DDE and HCB.

Effects of endogenous and exogenous hypercortisolemia on low-dose adrenocorticotropin test outcome in humans.

BACKGROUND: The results of low-dose ACTH testing may be impaired during endogenous or exogenous hypercortisolemia in various clinical situations. AIM: The hypothesized inhibitory effects of hypercortisolemia on adrenal responsiveness to low-dose ACTH were tested in two model situations in healthy humans. SUBJECTS AND METHODS: Nine young healthy women underwent low-dose ACTH test in 5 modifications. In ACTH-ACTH test, ACTH (1 microg iv) was given at 09:00 h and 10:00 h. Two control tests consisted of single ACTH bolus at 09:00 h or at 10:00 h. In hydrocortisone (HC)-ACTH test, HC (20 mg po) was given at 08:30 h and ACTH was injected at 10:00 h. Control test consisted of single HC administration at 08:30 h. RESULTS: Cortisol response after the 2nd ACTH test was significantly lower vs the 1st ACTH bolus (Deltamax: 166+/-32 nmol/l vs 276+/-15 nmol/l, p<0.05) in ACTH-ACTH test. Responses of other steroids after both ACTH injections were comparable. ACTH bolus during HC-induced hypercortisolemia caused a slight increase in cortisol level and prevented its decrease, seen after HC administration alone. Adrenal cortisol production in response to ACTH bolus under different incipient conditions (baseline, physiological, and pharmacological hypercortisolemia; 180+/-16, 173+/-21, and 177+/-53 nmol.min.l-1, respectively) did not significantly differ (p=0.8). CONCLUSIONS: Endogenous and exogenous hypercortisolemia did not influence adrenal cortisol response to low-dose ACTH test indicating lack of its negative feedback at adrenal level.

Hormone response to stress in rat strains of different susceptibility to immunologic challenge.

OBJECTIVE: The aim of this study was to compare the changes in plasma levels of hormones involved in modulation of the immune system function after exposure to stress in two rat strains with different susceptibility to immunoantigens. METHODS: Adult rat males of Lewis (LEW) and Fischer 344 (FIS) strains were exposed to restrain stress for 2 hours and blood samples were collected during stress exposure. Other groups of animals were exposed to restrain stress for 2 hours and sacrificed 3 hours later for blood and organ collection. Corticosterone, testosterone, dehydroepiandrosterone, 17beta-estradiol and progesterone were estimated by radioimmunoassay, epinephrine and norepinephrine levels were determined by radioenzymatic method. RESULTS: The levels of plasma corticosterone and catecholamines were significantly higher during stress exposure in FIS as compared to LEW rats. Greater decrease of testosterone levels and higher levels of estradiol were noted after exposure to stress in LEW rats. Higher values of progesterone plasma levels were noted in FIS rats after stress. CONCLUSIONS: These results demonstrated the differences in the response of catecholamines, adrenal and gonadal steroids after exposure to stress in LEW and FIS rats with lower levels of hormones with anti-inflammatory action in LEW rats.

Adrenomedullary response to hypoglycemia in first-degree relatives of patients with rheumatoid arthritis.

Our recent studies showed blunted adrenomedullary responses to insulin-induced hypoglycemia in premenopausal females with rheumatoid arthritis (RA) and systemic sclerosis, suggesting dysregulation of the adrenomedullary hormonal system (AMHS). Since no relationship has been found between degree of AMHS dysfunction and clinical or inflammatory parameters in those patients, we hypothesize the presence of an inherited perturbation of the AMHS. To test this hypothesis, we evaluated adrenomedullary responses to insulin-induced hypoglycemia (0.1 IU/kg) in premenopausal female subjects: 17 glucocorticoid-naïve RA patients, 15 healthy first-degree family members (FDR), and 18 age- and body mass index-matched healthy controls. Our results demonstrate that when compared to controls, RA patients had lower baseline epinephrine levels (P= 0.01) and lower area under response curve (AUC) levels of norepinephrine (P < 0.001) and epinephrine (P < 0.003). In contrast, FDR had lower (P= 0.001) AUC levels of norepinephrine compared to controls and higher (P= 0.033) AUC levels of epinephrine compared to RA patients. There were no significant differences in epinephrine response between FDR and controls. Although we found lower norepinephrine responses to hypoglycemia in FDR of RA patients, adrenomedullary responses to hypoglycemia does not appear to be altered to the degree found in RA patients.

Growth hormone response to different consecutive stress stimuli in healthy men: is there any difference?

The contribution of growth hormone (GH), released during acute and repeated stressful situations, to the development of stress-related disorders is often neglected. We have hypothesized that the modulation of the GH response to sequential stress exposure in humans depends mainly on the nature of the stressor. To test this hypothesis, we compared GH responses to different stressful situations, namely aerobic exercise, hypoglycemia and hyperthermia, which were applied in two sequential sessions separated by 80-150 min. In addition, administration of the dopaminergic drug apomorphine was used as a pharmacological stimulus. GH responses to submaximal exercise (bicycle ergometer, increasing work loads of 1.5, 2.0 and 2.5 W/kg, total duration 20 min) and hyperthermia in a sauna (80 degrees C, 30 min) were prevented when preceded by the same stress stimulus. Hypoglycemia induced by insulin (0.1 IU/kg intravenously) resulted in a significant GH response also during the second of the two consecutive insulin tests, though the response was reduced. Administration of apomorphine (0.75 mg subcutaneously) or insulin prevented the increase in GH release in response to a sequential bolus of apomorphine, while hypoglycemia induced a significant elevation in GH levels even if applied after a previous treatment with apomorphine. In conclusion, the feedback inhibition of the GH response to a sequential stress stimulus depends on the stimulus used. Unlike in the case of exercise and hyperthermia, mechanisms involved in the stress response to hypoglycemia appear to overcome the usual feedback mechanisms and to re-induce the GH response when applied after another stimulus.

[Levels of hormones in plasma and in synovial fluid of knee joint of patients with rheumatoid arthritis]. / Hladiny hormónov v plazme a v synovialnej tekutine kolenného klbu pri reumatoidnej artritíde.

BACKGROUND: Dysfunction of endocrine system is very likely one of the important risk factors involved in the pathogenesis of rheumatoid arthritis. The aim of the present study was to investigate the levels of selected hormones in plasma and in synovial fluid of knee joint of patients with rheumatoid arthritis or with osteoarthritis, which could affect the inflammatory processes. METHODS AND RESULTS: Thirty nine patients with rheumatoid arthritis (22 females and 17 males) and 12 patients with osteoarthritis (6 females and 6 males) were investigated. Concentrations of the following hormones were determined in plasma and synovial fluids: cortisol, 17-beta-estradiol, progesterone, dehydroepiandrosterone, aldosterone, testosterone, prolactin, insulin and C-peptide by using radioimmunoassay kits. Increased levels of 17-beta-estradiol and insulin were found in patients with rheumatoid arthritis as compared to those with osteoarthritis. The plasma concentrations of other hormones under study were not significantly different in these groups of patients. Higher levels of 17-beta estradiol, progesterone and aldosterone were noted in inflammatory knee exudate of patients with rheumatoid arthritis. The levels of other hormones in exudates of patients with rheumatoid arthritis and those with osteoarthritis were not significantly different. The ratio of 17-beta estradiol / cortisol, 17-beta estradiol / testosterone and 17-beta estradiol / dehydroepiandrosterone showed increased proportions of estrogens over androgens or glucocorticoids in exudate from patients with rheumatoid arthritis. CONCLUSIONS: These results demonstrated that steroid and peptide hormones are transferred to synovial fluid of knee. The presence of insulin, C-peptide and aldosterone was described for the first time in synovial fluid. In patients with rheumatoid arthritis a predomination of the levels of proinflammatory estrogens over androgens was found in knee exudate. Also the levels of aldosterone and progesterone were elevated in inflammation knee exudate. This suggests that these hormones present in synovial fluid may affect the local rheumatoid inflammatory processes.

Insulin sensitivity indices: a proposal of cut-off points for simple identification of insulin-resistant subjects.

Demanding measurement of insulin sensitivity using clamp methods does not simplify the identification of insulin resistant subjects in the general population. Other approaches such as fasting- or oral glucose tolerance test-derived insulin sensitivity indices were proposed and validated with the euglycemic clamp. Nevertheless, a lack of reference values for these indices prevents their wider use in epidemiological studies and clinical practice. The aim of our study was therefore to define the cut-off points of insulin resistance indices as well as the ranges of the most frequently obtained values for selected indices. A standard 75 g oral glucose tolerance test was carried out in 1156 subjects from a Caucasian rural population with no previous evidence of diabetes or other dysglycemias. Insulin resistance/sensitivity indices (HOMA-IR, HOMA-IR2, ISI Cederholm, and ISI Matsuda) were calculated. The 75th percentile value as the cut-off point to define IR corresponded with a HOMA-IR of 2.29, a HOMA-IR2 of 1.21, a 25th percentile for ISI Cederholm, and ISI Matsuda of 57 and 5.0, respectively. For the first time, the cut-off points for selected indices and their most frequently obtained values were established for groups of subjects as defined by glucose homeostasis and BMI. Thus, insulin-resistant subjects can be identified using this simple approach.