Exogenous orexin-A downregulates luteinizing hormone secretory activity in prepubertal female rats.

INTRODUCTION: Orexin-A is a neuropeptide synthesized in the lateral hypothalamus. Orexin-A immunoreactive fibres overlap distribution with GnRH neurons. In adult rats, orexin A is known to affect LH secretion via GnRH release modulation. Because data concerning the impact of orexin-A on the hypothalamo-pituitary axis activity are limited, we focused on the involvement of orexin-A and receptors of NPY in the modulation of LH release and LH subunit b (Lhb) mRNA expression in prepubertal female rats. MATERIAL AND METHODS: Forty immature female Wistar rats were divided into 4 groups and received 2 intracerebroventricular (icv) microinjections of: 1 - artificial cerebrospinal fluid (CSF) (controls); 2 - CSF followed by orexin A; 3 - selective NPY receptor antagonist (BIBP) followed by CSF; 4 - BIBP followed by orexin A. One hour after the last microinjection, all rats were decapitated. Trunk blood was collected, and serum was stored at -20°C for the LH RIA examination. The adenohypophysis was immediately excised, flash-frozen, and kept at -80°C for RNA extraction. Real-time PCR amplification was carried out, and relative Lhb gene expression was calculated. RESULTS: In comparison to the CSF-treated controls with a mean LH serum concentration of 0.40 ± 0.02 ng/mL, the mean LH serum level was diminished both after orexin-A (0.27 ± 0.01 ng/mL) and after BIBP (0.30 ± 0.02 ng/mL) icv microinjections. In the presence of BIBP, orexin-A more effectively inhibited LH release (0.20 ± 0.01 ng/mL) when compared to the BIBP-treated group. Orexin-A and BIBP exerted a consistent inhibitory effect on Lhb mRNA expression levels in the anterior pituitary gland. In comparison to the CSF-treated controls, orexin-A, and BIBP-treated females responded with, respectively, 35% and 40% reduction of Lhb mRNA expression. Orexin-A and BIBP co-administration evoked a further reduction of Lhb gene transcriptional activity. CONCLUSIONS: Orexin-A exerts a down-regulatory effect on LH synthesis and release in immature female rats. Considering that Y1R-oriented down-regulation of endogenous NPY activity did not reverse the suppressive effect of exogenous orexin-A, it might be suggested that NPY and orexin A systems can operate independently to affect gonadotropin activity in the anterior pituitary of the immature female rats.

The metabolic, neuroprotective cardioprotective and antitumor effects of the Klotho protein.

Klotho is a transmembrane protein with a wide spectrum of activity. The human Klotho gene shows 86% amino acid identity with the mouse protein. Many important pleiotropic functions of the Klotho protein have been revealed. Amongst them, there is a regulation of nitric oxide production, suppression of oxidative stress and inflammation, influence on the insulin-like growth factors and fibroblast growth factors signaling, modulation of calcium and phosphate metabolism, synthesis of vitamin D and other. Two forms of the Klotho protein are known. The secreted form strongly inhibits the oxidative stress, and, in humans, is more dominant than the membrane form. Studies on a mouse model resulted in the finding of the anti-aging effect of the Klotho protein. This activity is mainly associated with the suppression of oxidative stress, as well as it could be related to neuroprotective, cardioprotective, and metabolic functions.It might be speculated that Klotho, regarded as a neuroprotective factor, may have therapeutical applications in the future in the treatment of demyelinating and neurodegenerative disorders, especially multiple sclerosis (MS) and Alzheimer's disease (AD). The Klotho through inhibition of oxidative stress possesses cardioprotective properties. Of note, one functional variant of Klotho is a risk factor for coronary disease as well as some nucleotide polymorphisms are associated with carotid arteriosclerosis. Moreover, the Klotho protein can inhibit Angiotensin II-induced cardiomyocyte hypertrophy. All those effects indicate that the Klotho protein may be useful in the therapy of heart failure and hypertension. Undoubtedly, metabolic disturbances play an important role in the pathogenesis of many neurodegenerative and cardiovascular diseases. The metabolic effects of the Klotho protein are strongly connected with its neuroprotective and cardioprotective activity. This protein affects adipogenesis, metabolism of glucose and lipids as well as calcium-phosphate system by influence on the activity of fibroblast growth factors (FGF19, FGF23, FGF21). Finally, it has been revealed that the Klotho protein has antitumor activity. Besides, the FGF-Klotho system may have a role in longevity and aging-related disorders.

Peripheral levels of selected adipokines in patients with newly diagnosed multiple sclerosis.

INTRODUCTION: Multiple sclerosis (MS) is an autoimmune disease of the central nervous system. The exact aetiology is unknown. However, genetic and environmental factors are suggested to be involved in the pathogenesis of MS. Improper diet, resulting in obesity and metabolic syndrome, can contribute to this disease. Adipokines, secreted by adipose tissue, link the metabolism and immune system. MATERIAL AND METHODS: We aimed to assess plasma levels of selected adipokines in newly diagnosed, treatment-naïve individuals with multiple sclerosis. Our group comprised 58 individuals (31 MS patients and 27 controls, matched for age and BMI) without diabetes, hypertension, or dyslipidaemia. Circulating adiponectin and all adiponectin fractions, visfatin, and omentin concentrations were measured. Metabolic parameters were also assessed. RESULTS: In MS individuals we observed the following results: higher concentrations of visfatin, lower levels of omentin, and no differences in adiponectin array. There were also correlations between some adipokines and metabolic parameters. After adjustment to BMI, a significant decrease in total adiponectin, high-molecular weight (HMW) adiponectin and omentin, and an increase in medium-molecular-weight (MMW) adiponectin were observed in the group of MS patients when compared to those of the controls. CONCLUSIONS: Our results indicate that adiponectin with its fractions, visfatin, and omentin cannot be considered as causative factors in the early phase of multiple sclerosis. However, the potential role of adipokines in MS is possible because they might be involved in the pathogenesis of MS, regarded as an autoimmune disorder.

Copeptin - a new diagnostic and prognostic biomarker in neurological and cardiovascular diseases.

Copeptin, arginine vasopressin (AVP)-associated 39 aminoacid glycopeptide, is a C-terminal part of pro-AVP. AVP acts through V1a, V1b, and V2 receptors. The effect on V1a receptors is connected with arterial vasoconstriction, on V2 with antidiuretic action, and on V1b with the secretion of ACTH, insulin, glucagon. Copeptin is found in the circulation in equimolar amounts with AVP. It is a very stable peptide and easy to estimate. Copeptin is a good diagnostic marker in many disorders in which vasopressinergic dysfunction plays a role in pathogenesis such as a polyuria-polydipsia syndrome, neurological disease (ischemic stroke, nontraumatic, intracerebral hemorrhage, aneurysmal subarachnoid hemorrhage and neurodegenerative disease (multiple sclerosis). Copeptin is a diagnostic and prognostic marker in cardiovascular diseases like heart failure (HF) and acute myocardial infarct (AMI). Copeptin is a sensitive diagnostic marker in the early stage of AMI especially in patients with non-ST segment elevation and post AMI complications. Copeptin is also an important diagnostic and prognostic marker in metabolic diseases (diabetes mellitus, metabolic syndrome, insulin resistance), connected with some neurological and cardiovascular diseases. In the future, these findings may have also therapeutic applications in conditions where the AVP receptor antagonist therapy is appropriate.

Neuroendocrine aspects of anorexia nervosa and bulimia nervosa.

Endocrine dysfunctions in eating disorders (anorexia nervosa, bulimia nervosa) result from disturbed regulation of hypothalamo-pituitary-gonadal, hypothalamo-pituitary-adrenal, hypothalamo-pituitary-thyroid and hypothalamo-pituitary-GH-IGF1 axes as well as of altered peripheral endocrine metabolism. Some peptides of hypothalamic origin, as well as those secreted by the adipose tissue and gastrointestinal tract including pancreatic hormones, are involved in the control of appetite and satiety. These peptides play also an important role in the mechanism of hormonal secretion. Altered activity of these biologically active substances may lead to the disturbances in the regulation of energy and hormonal homeostasis.

Plasma adiponectin array in women with Alzheimer's disease.

Introduction Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disease. Typical features of AD include memory loss, social dysfunction and physical impairment. Although the pathological findings in the central nervous system are well established, the etiological factors are poorly known. Recent studies suggested the role of metabolic disturbances in the development of AD neurodegeneration. Adiponectin, an anti-inflammatory and metabolism regulating factor, was linked to AD. Aim The aim was to examine whether adiponectin fractions combined with insulin/insulin resistance-associated metabolic parameters correlate with AD progression. Material and methods The study comprised 98 women: 27 with moderate to severe AD, 31 with AD at early stage and 40 healthy controls, matched for age and BMI. To evaluate memory impairment, the MMSE was performed. Plasma total adiponectin and its high-, medium- and low molecular weights were measured with ELISA. Anthropometric, clinical and metabolic parameters were assessed. Correlations between adiponectin array and measured parameters were evaluated. Results In comparison to the controls, enhanced levels of total and medium molecular weight adiponectin characterized AD individuals. In AD, we found correlations between adiponectin array, and anthropometric and biochemical parameters. After adjustment to BMI, a significant increase of the total adiponectin and high- and medium molecular weight fractions was observed. A negative correlation between low molecular weight adiponectin and MMSE was found. Conclusions Our results indicate a possible link between adiponectin variations and AD. We hypothesize that changes in adiponectin profile observed in AD result from compensatory mechanism against neuropathological processes, as well as from adiponectin homeostasis impairment.

Adipokine profile in patients with anorexia nervosa.

INTRODUCTION: Anorexia nervosa (AN) is an eating disorder characterised with extremely low weight. Adipokines are adipose tissue-derived substances that show a wide spectrum of biological activities. We aimed to assess selected adipokine levels in women with AN before and after nutritional intervention. We also sought to examine whether BMI is the only confounding factor influencing adipokine assessment in AN. MATERIAL AND METHODS: Sixty-five women participated in the study: 20 individuals with AN before any treatment, 18 AN patients after nutritional intervention lasting for at least six months, and 27 women as controls. In all participants blood collection and anthropometric measurements were performed. ELISA was used for evaluation of leptin receptor, adiponectin and its isoforms, and resistin. Leptin was assessed with RIA, and visfatin was measured with EIA assay. RESULTS: Leptin and free leptin index (FLI) were lowest in treatment-naïve AN women. HMW-adiponectin and visfatin were enhanced in AN. Other adipokine levels showed no significant differences. When two subsets of anorexia nervosa were compared, only leptin, leptin receptor, and FLI were markedly different. When data were adjusted to BMI, leptin and FLI remained significantly different in the pre-treated AN subgroup when compared with the control group. CONCLUSIONS: Our results suggest that leptin is the most important adipokine in AN. It is also important that in our AN population leptin and FLI are the only factors that are influenced not only by the fat content.

Assessment of plasma brain-derived neurotrophic factor (BDNF), activity-dependent neurotrophin protein (ADNP) and vasoactive intestinal peptide (VIP) concentrations in treatment-naïve humans with multiple sclerosis.

OBJECTIVE: Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS) characterized by coexisting processes of inflammation, demyelination, axonal neurodegeneration and gliosis. Autoimmune processes play a pivotal role in the disease. The immune system may be modulated by neurotrophins and neurotrophin factors. Aim of the study was to assess plasma levels of brain-derived neurotrophic factor (BDNF), activity-dependent neurotrophin protein (ADNP) and vasoactive intestinal peptide (VIP) in treatment-naïve humans with newly diagnosed multiple sclerosis. We also elucidated the potential influence of selected inflammatory agents on peripheral concentration of BDNF and ADNP. MATERIAL AND METHODS: The study population comprised of 31 untreated patients with MS and 36 controls from a single hospital centre. Assessment of BDNF and ADNP was performed with use of ELISA methods. VIP was measured with RIA. Selected cytokine levels (IL 6, IL 10, and TNF α) were evaluated with ELISA tests. Statistical analyses were performed. RESULTS: We failed to find any significant differences between ADNP, BDNF, VIP, CRP levels and concentration of cytokines between individuals with MS and the controls. No correlation was observed between ADNP, BDNF and VIP as the first parameter and CRP, IL 6, IL 10, TNFα levels and the Expanded Disability Status Scale score in MS. CONCLUSIONS: Newly diagnosed, treatment-naïve patients with MS have comparable levels of plasma BDNF, ADNP and VIP to those of healthy controls.

Plasma leptin levels and free leptin index in women with Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by irreversible and progressive loss of memory and other cognitive functions. Controversies still exist on the precise mechanisms contributing to neurodegeneration. Obesity and disturbances in metabolic homeostasis are thought to be AD risk factors. Adipokine leptin has receptors in the brain, also in the regions related to AD. Leptin may protect against AD. The aim was to assess leptin and soluble leptin receptor levels in plasma as well as free leptin index (FLI) in correlation with metabolic status of women diagnosed with Alzheimer's disease. Eighteen women with moderate to severe stage of AD, 40 women with AD at early stage, and 42 female controls, matched for age and body mass index, participated in the study. Leptin and soluble leptin receptor levels were measured with RIA and IRMA, respectively. Then, FLI was calculated. In addition, metabolic parameters (lipid profile, glucose and insulin concentrations, HOMA-IR) were estimated. Clinical and anthropometric data were collected. The Mini-Mental State Examination (MMSE) as a cognitive impairment measurement was performed. Correlations with both leptin and FLI, and MMSE, clinical and biochemical parameters were evaluated. Leptin levels and FLI were significantly lower and leptin receptor concentrations were higher in AD subjects when compared with the controls. In AD group leptin, soluble leptin receptor and FLI correlated with selected metabolic parameters but not with MMSE. We conclude that alterations in leptin, leptin receptor, and FLI were the most intensified in advanced AD. However, these results did not correlate with dementia stage measured with MMSE. Therefore, further intensive research is needed to explain the mechanisms involved in this phenomenon.

Association of copeptin and cortisol in newly diagnosed multiple sclerosis patients.

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system. Obesity may increase the risk of developing MS. The aim of this study was to evaluate copeptin and cortisol plasma levels in newly diagnosed untreated MS patients and to determine whether copeptin and cortisol are related to the patients' clinical statuses. We report that copeptin and cortisol were higher in overweight/obese MS patients. Positive correlations were observed between the two parameters. We conclude that alterations of copeptin and cortisol levels in multiple sclerosis patients may be related to adiposity. An increase in cortisol may also be associated with copeptin secretion.

Plasma chemerin levels in patients with multiple sclerosis.

OBJECTIVES: Chemerin, a novel adipokine produced by adipose tissue and liver, is associated with markers of metabolic syndrome, and additionally, acting as chemoattractant for cells of immune system it may regulate immune cell properties. MATERIAL AND METHODS: In order to evaluate plasma chemerin concentration in multiple sclerosis (MS) individuals we investigated 39 MS patients (among them 23 subjects were lean and 16 were overweight or obese) and 42 controls with tension headaches (29 of them were lean and 13 were overweight or obese). All patients had a brain MRI scan with gadolinium contrast as well as an assessment of the presence of oligoclonal bands in cerebrospinal fluid (CSF) and estimation of the CSF IgG index. The neurologic status was evaluated with use of the Expanded Disability Status Scale. Chemerin levels in plasma were measured using ELISA kit. Lipid profile, glucose and insulin levels, CRP and selected cytokine concentrations were also determined. RESULTS: Plasma chemerin concentrations in overweight/obese MS subjects were higher when comparing to lean MS individuals and the controls, both from lean and overweight/obese subgroups. Significant difference was found between the results of overweight/obese MS and lean controls. CONCLUSIONS: An increase of chemerin levels in patients with multiple sclerosis is associated with overweight and obesity.

Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating polypeptide (PACAP) in humans with multiple sclerosis.

Multiple sclerosis (MS) is a chronic neuroinflammatory disease of the central nervous system that leads to demyelination and neurodegeneration. VIP and PACAP are structurally related neuropeptides with neuroprotective and anti-inflammatory activities. To evaluate VIP and PACAP-38 in plasma and CSF in humans in correlation with IL-6, IL-10 and TNFα, we compared 20 MS individuals with 27 healthy controls. In MS, a decrease in PACAP-38 in CSF and a decrease in plasma IL-6 concentration were seen. A positive correlation between plasma VIP and plasma IL-6 was identified. We conclude that VIP and PACAP may influence the course of MS.

Plasma NPY concentrations in women with acute ischemic stroke.

OBJECTIVE: It has been reported that plasma NPY levels were increased in obesity, type 2 diabetes mellitus and hypertension. The symptoms of metabolic syndrome frequently appear in patients with acute ischemic stroke. The association between plasma NPY levels and metabolic markers in women with acute ischemic stroke was investigated in the current study. METHODS: Plasma NPY concentrations were determined using radioimmunoassay in 58 women aged 60-85 (mean age: 76.5±0.8) with acute ischemic stroke and in 24 women aged 63-67 (mean age: 65.6±0.6) of the control group. Stroke was defined according to the NIHSS (National Institute of Health Stroke Scale) and was confirmed using CT or MR scan. RESULTS: The prevalence of type 2 diabetes, hypertension and insulin resistance was higher in the group of patients with stroke. Plasma NPY levels measured during the 1st day and 10 days after the acute phase of stroke were significantly lower (p<0.001) compared to the control group. CONCLUSION: In women with acute ischemic stroke plasma NPY concentrations were decreased in spite of higher frequency of the occurrence of the symptoms of metabolic syndrome.

Assessment of adiponectin and its isoforms in Polish centenarians.

BACKGROUND: The physiological mechanisms that promote longevity remain unclear. It has been suggested that insulin sensitivity is preserved in centenarians, whereas typical aging is accompanied by increasing insulin resistance. The oldest-old individuals display raised total adiponectin levels, despite the potential correlation between enhanced adiponectin and all-cause and cardiovascular mortality. AIM: To evaluate the level of adiponectin and its isoforms in sera of centenarians and to assess associations between adiponectin and metabolic parameters. PARTICIPANTS: A group of 58 Polish centenarians (50 women and 8 men, mean age 101±1.34 years) and 68 elderly persons (55 women and 13 men, mean age 70±5.69 years) as controls. MEASUREMENTS: Serum samples were analyzed to evaluate the following parameters: adiponectin array (total adiponectin, HWM-, MMW- and LMW-adiponectin; all by ELISA methods), insulin (by IRMA methods), glucose and lipid profiles. HOMA-IR was calculated. Clinical data were collected. Statistical analyses were performed. RESULTS: The concentrations of all adiponectin isoforms were significantly higher in the oldest-old participants. In the centenarian group, total adiponectin positively correlated with age and HDL-cholesterol, and HMW-adiponectin was negatively associated with insulin and triglycerides. The long-lived participants had a lower incidence of hypertension, type 2 diabetes, overweight and obesity, with lower concentrations of serum glucose and insulin, and reduced HOMA-IR. CONCLUSION: Our findings support the thesis that centenarians possess a different adiponectin isoform pattern and have a favorable metabolic phenotype in comparison with elderly individuals. However, additional work is necessary to understand the relevance of these findings to longevity.

Resistin levels in women with ischemic stroke.

OBJECTIVES: Resistin may be an independent inflammatory marker of atherosclerosis. Therefore, its circulating level might be important prognostic factor of cardiovascular disease in humans. We aimed in this study to assess plasma resistin concentration in Polish women with acute ischemic stroke, who additionally suffer from chronic diseases: diabetes, hypertension and/or obesity. The changes of resistin levels after 10 days from the onset of stroke and possible associations between resistin and pro-inflammatory cytokine TNFα were also evaluated. MATERIAL AND METHODS: Material consisted of 41 women with ischemic stroke (aged 60-85 years) and 64 controls (aged 60-85 years). Circulating resistin and TNFα concentrations were measured using ELISA. Blood was taken twice in the stroke group, in the first and tenth day from the onset of clinical symptoms, and only once in the controls. Clinical and biochemical data (blood pressure, weight, height, glucose, insulin, lipid profile) were collected. RESULTS: Higher concentrations of resistin and TNFα were observed in ischemic stroke patients at the first day comparing to the controls. Second evaluation after 10 days in comparison with the first measurement revealed significantly higher TNFα levels and non-significant lower values of resistin. Resistin positively correlated with TNFα and stroke severity. CONCLUSIONS: Changes in resistin and TNFα concentrations were observed in the course of stroke. Further investigations are required to assess the implication of these findings. Higher resistin concentration might be associated with worse neurological deficits.

Identification of a late onset Alzheimer's disease candidate risk variant at 9q21.33 in Polish patients.

Late onset Alzheimer's disease (LOAD) accounts for about 95% of all Alzheimer's disease cases. While the APOE ε4 variant seems to have unparalleled influence on increased LOAD risk, it does not explain all of the heritability of LOAD. In this study, we present the application of a cost-effective, pooled DNA genome-wide association study (GWAS) to uncover genetic risk variants associated with LOAD in Polish women diagnosed with either mild cognitive impairment (MCI) or well-defined LOAD. A group of 141 patients (94 LOAD and 47 MCI), as well as 141 controls, were assayed using Affymetrix Genome-Wide Human SNP 6.0 arrays. Allele frequency distributions were compared using χ(2)-tests, and significantly associated SNPs at p < 0.0001 with a proxy SNP were selected. GWAS marker selection was conducted using PLINK, and selected SNPs were validated on DNA samples from the same cohort using KASPar Assays. In addition, to determine the genotype of APOE variants (rs429358, rs7412), a multiplex tetra-primer amplification refractory mutation system was applied. The GWAS revealed nine SNPs associated with MCI and/or LOAD. Of these, the association of seven SNPs was confirmed by genotyping of individual patients. Furthermore, the APOE ε4 appeared to be a risk variant for LOAD, while the APOE ε3 showed a protective effect. Multivariate analysis showed association between rs7856774 and LOAD, independently from the effect of APOE variation. Pooled DNA GWAS enabled the identification of a novel LOAD candidate risk variant, rs7856774 (9q21.33), tagging a possible genomic enhancer affecting proximal transcribed elements including DAPK1 gene.

The evaluation of estradiol and leptin action on the activity of the somatotropic and gonadotropic axes in peripubertal female rats.

OBJECTIVE: Available data suggest that estrogens and leptin play a role in the control of the pubertal process. In humans and some mammal species the increase of the activity of gonadotropic axis accompanies the decrease in the rate of growth at puberty. The effect of 17ß-estradiol and/or leptin administration on the somatotropic and gonadotropic axes was studied using prepubertal female rats as an animal model. MATERIAL AND METHODS: Prepubertal female rats received estradiol/saline, estradiol/leptin, oil/leptin or oil/saline (vehicles) respectively. The changes of growth rate, and serum 17ß-estradiol, leptin, GH, IGF-I and gonadotropins levels as well as LHRH and estrogen receptor (ER) concentrations in the medial basal hypothalamus (MBH) and the pituitary were determined. All hormones concentrations were measured by radioimmunoassay and ER by radioligand methods . RESULTS: In estradiol and/or leptin treated animals noticeable reduction of rate of growth was found. The decrease of growth in response to estradiol treatment accompanied the increase GH level and the decrease of IGF-I concentration in the circulation. Both hormones operating together activated reproductive axis, what was manifested by a significant increase of LHRH abundant in the hypothalamus as well as elevated LH and FSH levels in the circulation. In these rats a significant decrease of the estrogen receptor concentrations in the pituitary was observed. CONCLUSION: The role of estradiol and leptin in the control of growth and reproduction seems to overlap only partially. Estradiol plays a significant role in the activation of the reproductive axis, and leptin takes part as a permissive factor in pubertal process.

Do novel adipokines play a causative or only modulating role in the pathogenesis of obesity and metabolic disorders?

Adipose tissue is an endocrine and paracrine organ that releases a large number of bioactive mediators. Approximately 100 adipokines have been identified including cytokines, chemokines, growth factors and enzymes. The use of adipoproteomic analyses resulted in new findings and, in consequence, the number of new adipokines is rising rapidly. Novel adipokines such as visfatin, vaspin and omentin were discovered about five years ago. Visfatin and vaspin production and secretion take place in adipocytes, but omentin comes from the stromal cells of adipose tissue. Several differences are noticeable between these adipokines especially in correlation with obesity as visfatin and vaspin serum levels increase in obese subjects while omentin serum levels decrease. It has been suggested that these adipokines act as insulin-sensitizers/insulin-mimetics. Increasing number of publications reporting the role of new adipokines does not allow to assess clearly the influence of those adipokines on the pathogenesis of obesity.

Decreased total serum adiponectin and its isoforms in women with acute ischemic stroke.

OBJECTIVE: An association between cerebral infarct risk factors and serum adiponectin levels (both total and separate isoforms) has previously been identified. The aim of this study was to assess circulating levels of all forms of adiponectin in the course of an ischemic stroke. MATERIAL AND METHODS: Adiponectin and its isoforms (HMW, MMW and LMW) were measured in serum samples taken from 38 women in the first 24 hours of cerebral infarct and 38 controls matched for gender, body mass index (BMI) and age. In addition, biochemical parameters (glucose, insulin, lipid profile) and clinical data (blood pressure, weight, and height) were evaluated. RESULTS: A significant reduction in serum levels of adiponectin and all examined fractions of this adipokine was observed in women suffering from acute ischemic stroke, compared with the matched controls. CONCLUSIONS: Differences in the serum adiponectin array between stroke subjects and controls were identified and further studies are required to investigate the clinical implications of this finding.

The influence of cocaine-amphetamine regulated transcript (CART) on pituitary hormones, corticosterone and leptin levels in starved rats.

OBJECTIVE: CART is involved in the control of food intake and hormonal secretion. We aimed to evaluate the effects of CART on hormonal profile in starved rats. METHODS: Study group included 100 male rats. Under conditions of food limitation CART (55-102) was given centrally (icv) or peripherally (iv). Non-starved animals underwent identical procedure. Vehicle (aCSF or saline)-injected rats served and as a controls. 60 minutes after CART or vehicle administration blood was collected to assess pituitary hormones (LH, FSH, PRL, GH, ACTH, TSH), corticosterone and leptin concentrations. RESULTS: Itracerebroventricular CART injection resulted in a significant increase in PRL, GH and corticosterone concentrations in non-starved rats compared with vehicle injected animals. However, in a group of starved animals only leptin levels were decreased in comparison with fasted controls. Peripheral CART administration caused a significant increase in PRL, GH and TSH levels in non-starved rats but no changes in investigated hormone levels were observed in starved animals when compared to saline injected controls. CONCLUSIONS: Our results indicate that CART is able to modulate hormonal profile in a non-starved rats. However, the modulatory effect depends on the CART administration method. Interestingly, CART administration, both icv and iv, does not have an impact on pituitary hormones and corticosterone levels in a course of food limitation.