Hanna Krauss

The effect of bradykinin on the oxidative state of rats with acute hyperglycaemia

Many clinical and experimental studies have established the beneficial effect of kinins in hypertension, heart failure and ischaemia-reperfusion syndrome, but little attention has been given to the role of kinins in hyperglycaemic conditions. The purpose of the present study was to determine the influence of bradykinin on the levels of glucose, insulin, malondialdehyde and hydrogen peroxide, as well as antioxidative enzyme activity in rats with streptozotocin (STZ)-induced acute hyperglycaemia. In STZ-induced hyperglycaemic rats the levels of glucose, hydrogen peroxide and malondialdehyde were increased by 256% (from 6.0+/-0.3 to 21.4+/-1.3 mmol/l, P<0.001), 33% (from 1.9+/-0.1 to 5.6+/-0.3 mmol H(2)O(2)/ml, P<0.001) and 19% (from 3.7+/-0.3 to 4.9+/-0.2 nmol/l, P<0.001) respectively. The activity of superoxide dismutase, catalase and glutathione peroxidase and the level of insulin were decreased by 46% (from 1367+/-73 to 737+/-59 U/g Hb, P<0.001), 36% (from 2.3+/-0.3 to 1.4+/-0.1 U Bergmayera/g Hb, P<0.001), 31% (from 236+/-19 to 163+/-24 U/g Hb, P<0.001) and 91% (from 47.5+/-1.7 to 2.4+/-0.5 mU/l, P<0.001) respectively in rats treated with streptozotocin. The administration of bradykinin caused the decrease in glucose, hydrogen peroxide and malondi-aldehyde levels by 38% (from 21.4+/-1.3 to 13.3+/-1.0 mmol/l, P<0.001), 37% (from 5.6+/-0.3 to 4.3+/-0.2 mmol H2O2/ml, P<0.001), 39% (from 4.9+/-0.2 to 3.0+/-0.2 nmol/l, P<0.001) respectively and the increase in insulin level and superoxide dismutase, catalase and glutathione peroxidase activity by 62% (from 2.4+/-0.5 to 4.0+/-0.4 mU/l, P<0.001), 23% (from 736.8+/-58.5 to 906.7+/-47.8 U/g Hb, P<0.001), 23% (from 1.4+/-0.1 to 1.9+/-0.1 U Bergmayera/g Hb, P<0.01) and 19% (from 163.1+/-23.6 to 202.3+/-11.7 U/g Hb, P<0.001) respectively in rats with hyperglycaemia. Thus, bradykinin is able to reduce oxidative stress in hyperglycaemic conditions.

Fasting and postprandial levels of ghrelin, leptin and insulin in lean, obese and anorexic subjects

Introduction Ghrelin, leptin and insulin are involved in neurohormonal regulation of energetic homeostasis. Aim We investigated the correlation between nutritional status and plasma levels of leptin, ghrelin and insulin in lean, obese and anorexic subjects. Material and methods Nineteen obese and 18 anorexic adults were enrolled in the study. Seventeen adults with normal body mass index (BMI) served as controls. Blood samples were taken twice: before breakfast and 2 h after breakfast. Fasting and postprandial ghrelin, leptin and insulin were examined. The following correlations were estimated: between BMI and basal level of tested hormones, between insulin and ghrelin, and between insulin and leptin. The threshold level of significance was p ≤ 0.05 for all calculations. Results Basal insulin level was lowest in anorexic patients and greatest in obese subjects. Fasting plasma ghrelin was lower in obesity and higher in anorexia as compared with the controls. Comparing with controls, fasting leptin levels were higher in obese and lower in anorexic subjects. There was positive correlation between BMI and basal leptin level in obesity. A significant postprandial increase was noted for insulin in all studied groups. Increased leptin and decreased ghrelin levels were detected 2 h after a meal in the control group. In obese patients, postprandial leptin was lower than before food intake, and fasting leptin showed positive correlation with basal insulin level. Conclusions Basal plasma ghrelin, leptin and insulin levels differ according to nutritional status. Impaired ghrelin and leptin secretion and insulin sensitivity may be involved in the pathogenesis of eating disorders.

Urinary tract infection during pregnancy affects the level of leptin, ghrelin and insulin in maternal and placental blood.

Abstract Aim. We examined ghrelin, leptin and insulin in maternal blood during normal pregnancy and pregnancy complicated by urinary tract infection (UTI), as well as in cord blood at labor. Methods. A total of 36 delivering women with history of UTI during the third trimester of pregnancy were enrolled in the study; 12 healthy pregnant women served as a control. Infection markers (CRP and procalcitonin) were determined in maternal blood during the course of UTI and at labor. Ghrelin, leptin and insulin were determined during labor in venous maternal and in umbilical cord blood. Results. We found negative correlation between infection markers in maternal blood during UTI, and level of tested hormones in cord blood, indicating potential risk of placental impairment due to energetic imbalance. We noted lower level of leptin in mothers with UTI and no change in leptin from umbilical blood comparing subjects with and without UTI. Low level of ghrelin was observed in maternal and cord blood when pregnancy was complicated by UTI. Insulin concentrations were high in mothers with UTI and low in their newborns cord blood. Increased maternal insulin level could indicate peripheral insulin resistance caused by the infection. Conclusion. UTI during pregnancy affects the concentration of hormones responsible for regulating energetic homeostasis within the placenta.

The role of ghrelin, leptin and insulin in foetal development

INTRODUCTION AND OBJECTIVE The growing epidemic of childhood obesity has forced scientists to search for methods to prevent feeding disorders. Increasing interest in appetite regulating hormones has revealed their influence on energy homeostasis after birth or even in utero. STATE OF KNOWLEDGE The presence of ghrelin in the stomach of human foetuses and the distinctive production in the pancreas of neonates suggests the role of ghrelin in pre- and post-natal development. The neonatal period appears to be a critical time for the formation of adipose tissue-hypothalamus circuits, thus the amount of adipocytes in foetal life may be a major regulator of food intake. Insulins orexigenic effect in the arcuate nucleus of the hypothalamus can be a major modulator of foetal development. OBJECTIVE This review, based on available literature, aims to analyses the role of appetite regulating hormones in foetal development. SUMMARY Different concentrations of hormones, such as ghrelin, leptin and insulin during foetal life raises the question whether or not they can be modulated, thereby avoiding obesity before birth. Children with pancreas agenesis showed smaller body size at birth, which emphasises the probable role of insulin in foetal growth. Study of sheep foetuses with IUGR confirmed these finding. Appetite-regulating hormones show different roles in foetal development and seem to be essential in the perinatal period.

Effects of living environment on the postoperative Scoliosis Research Society-24 results in females with adolescent idiopathic scoliosis

Summary Background There are many factors influencing postoperative health-related quality of life of adolescent idiopathic scoliosis patients, including the degree of the deformity, culture, differences in geography, rural versus urban living environments, and social factors. The objective of this study was to analyze the significance of geographic factors and their differences influencing the postoperative quality of life in females with adolescent idiopathic scoliosis residing in urban and rural environments, by use of the Polish version of the SRS-24 questionnaire. Material/Methods Forty urban and 20 rural postoperative patients with adolescent scoliosis with a minimum 2-year follow-up period after surgery were included in the study. The process of cross-cultural adaptation was performed according to the IQOLA Project. Results General results of the Polish SRS-24 equalled 4.1 (SD 0.5) and 4.0 (SD.0.5) in the rural and urban groups of patients, respectively. The 2 groups do not differ in incidence of floor and ceiling effects. The Cronbach’s alpha values are excellent for the general result of SRS-24 in urban and rural groups (0.85 and 0.85, respectively). The sub-groups differed significantly in the self-image after surgery domain (p=0.048). Conclusions Patients from the rural group scored higher in the self-image after surgery domain but reported higher pain levels when compared to urban patients. The associations between SRS-24 results and radiographic parameters in the rural group of patients were strong, compared with moderate relations reported in the urban group.

Influence of short-term L-arginine supplementation on carbohydrate balance in rats with ischemia-reperfusion syndrome

BACKGROUND There are studies showing stimulative effect of arginine on insulin secretion. This mechanism is not fully explained. The effects of the impact of arginine on carbohydrate balance under the conditions of ischemia and reperfusion remain to be determined. The aim of this study is the evaluation of the influence of short-term L-arginine supplementation on the concentration of glucose and insulin in blood and insulin binding in rat skeletal muscle under the conditions of ischemia and reperfusion. METHODS The study was conducted on male Wistar rats with average body mass 250 ± 30 g. Animals were divided into four groups: Group I - control, Group II - placebo, Group III - L-arginine 500 mg/kg/24 h for 5 days, Group IV - L-arginine and L-NAME (75 μmol/rat/24 h) for 5 days. Each group was divided into subgroups depending on duration of ischemia and reperfusion. Acute ischemia of hind limb was induced in each group by putting pneumatic tourniquet on the thigh. Blood samples and skeletal muscles were collected from the rats. Plasma concentrations of glucose and insulin were measured. Insulin binding to insulin receptors was determined in skeletal muscle. RESULTS A clear reduction of insulin binding to receptor was found in the group of animals without ischemia and the group supplemented with L-arginine and subjected to 4-h ischemia and 30- and 120-min reperfusion. A significant increase in insulin level was found in groups of animals with L-arginine and/or L-NAME subjected to 4-h ischemia at all times of reperfusion. Supplementation with L-arginine and/or L-NAME decreased levels of glucose in blood serum of animals undergoing ischemia-reperfusion syndrome compared to the control and placebo groups. CONCLUSION Under conditions of ischemia-reperfusion, short-term administration of L-arginine causes a decrease in insulin binding capacity of insulin receptors in skeletal muscle, an increase in insulin level and a decrease in the concentration of glucose in blood serum.

Association of cord blood ghrelin, leptin and insulin concentrations in term newborns with anthropometric parameters at birth.

Abstract Background: Ghrelin, leptin and insulin, generally considered as regulators of energy homeostasis of the organism may be related to fetal and early postnatal growth. Numerous studies have confirmed the presence of these hormones in the cells of the fetus indicating their importance in development at early stages of life. Methods: This study analyzed active and total ghrelin by radioimmunoassay (RIA), leptin and insulin concentrations by enzyme-linked immunosorbent assay (ELISA) in 65 cord blood samples, from term newborns, and measured the birth anthropometric parameters [birth weight (BW), head circumference, chest, stomach, thigh and arm circumference]. Results: Active ghrelin (AG) concentrations correlated negatively with BW, head circumference, stomach and thigh circumference. When divided by gender, AG correlated negatively with males’ BW, stomach and thigh circumference. Females’ head circumference correlated negatively with AG. Cord leptin correlated positively with arm circumference. When divided by gender, cord leptin was positively associated with BW and stomach circumference in male newborns and with thigh and arm circumference in female newborns. Insulin concentrations tended to correlate positively with BW in male newborns. Conclusions: In summary, it was confirmed that cord blood ghrelin, leptin and insulin correlate with anthropometric parameters at birth. This study showed a negative correlation of AG with anthropometric parameters, which may emphasize that this hormone is an indicator of growth restriction. This is in contrast to cord leptin and insulin, which are more connected with overgrowth. Taking all the results into consideration, the metabolic status of the fetus and newborn is an essential component in understanding the regulation of perinatal development.

Relationship between adipokines and lipid profile in postmenopausal women with different apolipoprotein E genotypes.

ABSTRACT The aim of the authors of this study was to clarify the relationships among apolipoprotein E (ApoE) genotype, blood pressure, lipid profile, serum leptin, and adiponectin in healthy postmenopausal women. The study was conducted between March 2011 and December 2012 on 266 participants aged 50–65 years from the Institute of Rural Health in Lublin, Poland. Results showed that women had four combinations of genotypes: ɛ2/ɛ3, ɛ3/ɛ3, ɛ3/ɛ4, and ɛ4/ɛ4. Carriers of different genotypes did not differ in terms of age, body mass index (BMI), blood pressure, total cholesterol, high-density lipoprotein (HDL) cholesterol, and adiponectin levels. Mean low-density lipoprotein (LDL) cholesterol levels were higher in ε4 carriers compared to non-carriers. Fasting serum leptin concentrations were higher in homozygotes ɛ4/ɛ4. Leptin correlated positively with BMI in all study groups and with LDL in ɛ2/ɛ3, ɛ3/ɛ3, and ɛ3/ɛ4. Adiponectin correlated negatively with triglycerides in ɛ2/ɛ3, ɛ3/ɛ3, and ɛ3/ɛ4 and positively with HDL in ɛ2/ɛ3 carriers. Adipokines were not associated with blood pressure. Multiple regression analyses demonstrated associations among leptin, ApoE ɛ4/ɛ4, BMI, and LDL, and among adiponectin, BMI, and triglycerides. In healthy postmenopausal women ɛ4/ɛ4 genotype was associated with lower leptin levels. Homozygosity ɛ4/ɛ4 was associated with a more atherogenic lipid profile and possibly dysregulation of leptin and adiponectin signaling in lipid metabolism.

The influence of short-term l-arginine supplementation on rats’ muscular and hepatic cells in ischemia–reperfusion syndrome

Due to the complex mechanisms of l-arginine activity, it is difficult to determine the clinical significance of supplementation with this amino acid. The objective of this study was to determine the influence of short-term supplementation with l-arginine in stress conditions, induced by ischemia–reperfusion syndrome, by assessing the damage to muscular and hepatic cells on the basis of creatine kinase (CK), alanine aminotransferase (ALAT) and aspartic aminotransferase (AspAT) activity in blood and the level of oxygen free radicals in analyzed tissues of rats. We observed that induced ischemia of hind limb caused an increase in CK, ALAT and AspAT activity and an increase in the level of free radicals in liver, but not in skeletal muscle. Supplementation with l-arginine led to a reduction in serum activity of CK and AspAT and reduction of the level of free radicals in analysed tissues. Simultaneous supplementation with l-arginine AND l-NAME resulted in a reversal of changes induced by l-arginine supplementation in the case of AspAT and free radicals in skeletal muscle. The results indicate that under conditions of ischemia–reperfusion, short-term administration of l-arginine has a protective effect on skeletal muscle manifesting itself by reduction of CK in the serum and reduction of free radicals level in THIS tissue.

Evaluation of antihypertensive effect of l-arginine supplementation in patients with mild hypertension assessed with ambulatory blood pressure monitoring

BACKGROUND Arterial hypertension is one of the most important cardiovascular risk factors, featuring the unsatisfactory efficacy of current therapies. The cardiovascular disease paradigm which assumes a crucial role of the endothelial phenotype in shaping the state of the circulatory system has become increasingly dominant and endothelial dysfunction should be treated as avidly as the diseases of other organs. The most valued current anti-hypertensive therapies exert a positive influence on the endothelium due to their pleiotropic effects, but the search for new effective strategies aimed at improving endothelial function is underway. L-arginine trials are part of this quest. The few L-arginine studies in hypertension have brought inconclusive results. The aim of this study was to evaluate the anti-hypertensive efficacy and safety profile of L- arginine during four weeks of oral supplementation to healthy subjects and patients diagnosed with primary mild hypertension. MATERIAL/METHODS The study was completed by 54 participants. Ambulatory blood pressure monitoring (ABPM) was used to allot patients to either a healthy control group (19 subjects) or the hypertensive treatment group (35 patients). Later the patients were randomized to either L-arginine (2 or 4 g three times daily or placebo. All participants underwent physical examination and had all basic lab tests and ABPM performed. RESULTS Blood pressure (both systolic and diastolic) by ABPM showed statistically significant lowering after 4 weeks of L-arginine supplementation only in the subgroup of patients treated with 12 g of L-arginine daily, with a stronger hypotensive effect observed during the day. CONCLUSIONS The present findings demonstrate a strong association between L-arginine supplementation and blood pressure reduction.