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Ghrelin Concentrations (ghrelin + concentration)
Kinds of Ghrelin Concentrations Selected AbstractsEffect of ovariectomy and ad libitum feeding on body composition, thyroid status, ghrelin and leptin plasma concentrations in female dogs,JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1-2 2006I. Jeusette Summary The objective of this study was to evaluate the effects of ovariectomy (i) and ad libitum feeding (ii) on energy intake, body weight (BW), body composition, thyroid status, leptin and ghrelin plasma concentrations. Four young adult female Beagle dogs were fed a maintenance diet for 6 weeks prior to ovariectomy, then 6 months after. Food allowance was adjusted in order to maintain optimal BW. Then, a diet slightly higher in energy concentration was fed ad libitum for 4 months. The maintenance diet was then fed ad libitum for one additional month. The maintenance of optimal BW after ovariectomy required a significant decrease in energy allowance. No increase in fat mass was observed. Ghrelin concentration remained unchanged. During the first month of ad libitum feeding, plasma ghrelin concentration and energy intake increased, then they decreased. Mean BW, plasma leptin, thyrotropin (TSH), total triiodothyronine (TT3) and total thyroxine (TT4) concentrations significantly increased over the study. The BW increase was exclusively due to an increase in body fat. In conclusion, energy allowance should be strictly controlled in spayed female dogs. The results suggest that in dogs, thyroid hormones, leptin and ghrelin concentrations change in response to a positive energy balance in an attempt to limit weight gain. However, the significant weight gain shows that this goal was not achieved. [source] 2127: Ghrelin concentration in the aqueous humour and plasma in open angle glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2010A KATSANOS Purpose Ghrelin is a peptide hormone that exerts metabolic and smooth muscle-relaxant effects in ocular tissues. The aim of this study was to compare aqueous humor and plasma levels of ghrelin in patients with open angle glaucoma (OAG) and controls. Methods Twenty four OAG, including 7 pseudoexfoliation (PXG) and 17 primary open-angle glaucoma (POAG) patients, and 30 controls were included. All participants were patients scheduled for cataract or glaucoma surgery. Patients with other concomitant ocular disease, previous ocular surgery or diabetes were excluded. Blood samples were collected before cataract surgery. Aqueous humor was aspirated from the anterior chamber through a paracentesis with a 27 G needle under sterile conditions. Ghrelin levels in both samples were measured quantitatively with commercially available Radioimmunoassay (RIA) kits. Results Mean±SD age was 71.0±9.3 and 69.6±6.6 years in the OAG and control groups, respectively (p=0.6). Plasma levels of ghrelin were 495.6±157.7 pg/ml in the OAG and 482.2±125.4 pg/ml in the control group, respectively (Mann-Whitney test, p=0.9). Aqueous humor levels of ghrelin were 85.5±15.4 pg/ml and 123.4 ±25.5 pg/ml in the OAG and control groups, respectively (Mann-Whitney test, p<0.01). The ratio of plasma/aqueous concentration in ghrelin was higher in the OAG versus the control group (5.82± 1.94 versus 4.00±1.04, Mann-Whitney test, p<0.01). There was no difference neither in plasma nor in aqueous humor levels of ghrelin between POAG and PXG patients (p>0.5). Conclusion Aqueous humor levels of ghrelin were significantly lower in OAG patients. This difference may manifest a role of ghrelin in the disease process or a consequence of antiglaucoma treatment. [source] Effect of ovariectomy and ad libitum feeding on body composition, thyroid status, ghrelin and leptin plasma concentrations in female dogs,JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1-2 2006I. Jeusette Summary The objective of this study was to evaluate the effects of ovariectomy (i) and ad libitum feeding (ii) on energy intake, body weight (BW), body composition, thyroid status, leptin and ghrelin plasma concentrations. Four young adult female Beagle dogs were fed a maintenance diet for 6 weeks prior to ovariectomy, then 6 months after. Food allowance was adjusted in order to maintain optimal BW. Then, a diet slightly higher in energy concentration was fed ad libitum for 4 months. The maintenance diet was then fed ad libitum for one additional month. The maintenance of optimal BW after ovariectomy required a significant decrease in energy allowance. No increase in fat mass was observed. Ghrelin concentration remained unchanged. During the first month of ad libitum feeding, plasma ghrelin concentration and energy intake increased, then they decreased. Mean BW, plasma leptin, thyrotropin (TSH), total triiodothyronine (TT3) and total thyroxine (TT4) concentrations significantly increased over the study. The BW increase was exclusively due to an increase in body fat. In conclusion, energy allowance should be strictly controlled in spayed female dogs. The results suggest that in dogs, thyroid hormones, leptin and ghrelin concentrations change in response to a positive energy balance in an attempt to limit weight gain. However, the significant weight gain shows that this goal was not achieved. [source] Plasma ghrelin concentration is a signal of decreased fat free mass in healthy elderly femalesAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2009Jaak Jürimäe This study aimed to evaluate whether circulating ghrelin is associated with changes in different body composition parameters over a 12-month prospective study period in healthy older females. On 41 postmenopausal women (mean age: 71.0 ± 6.5 years), ghrelin, leptin, insulin resistance (IR), and body composition parameters were assessed before and after the study period. Trunk fat: leg fat ratio (+3.6%), fat free mass (FFM) (,4.1%), glucose (+5.8%), and IR (+7.0%) were significantly changed (P < 0.05), whereas no changes in height, body mass, body mass index, fat mass (FM), %FM, trunk fat, leptin, ghrelin, and insulin were observed as a result of study period. At baseline, ghrelin correlated negatively (r > ,0.306; P < 0.05) with body mass, FM, %FM, trunk fat, FFM, leptin, insulin, and IR. Multivariate linear regression analysis demonstrated that baseline ghrelin concentration was significantly associated only with the mean change in FFM value over the 12-month study period. In conclusion, basal ghrelin concentration predicted the loss of FFM in healthy elderly females. In addition, these results suggest that circulating ghrelin concentration could be regarded as a signal of decreased FFM in healthy elderly females. Am. J. Hum. Biol., 2009. © 2009 Wiley-Liss, Inc. [source] Leptin and ghrelin concentrations and weight loss in Parkinson's diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 4 2010U. Fiszer Fiszer U, Micha,owska M, Baranowska B, Woli,ska-Witort E, Jeske W, Jethon M, Pia,cik-Gromada M, Marcinowska-Suchowierska E. Leptin and ghrelin concentrations and weight loss in Parkinson's disease. Acta Neurol Scand: 2010: 121: 230,236. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives,,, To investigate the role of leptin, ghrelin, GH and IGF-1 in energy balance disturbances in Parkinson's disease (PD). Materials and methods,,, Thirty-nine patients were included: 11 PD patients with unintentional weight loss, 16 PD patients without weight loss and 12 controls. UPDRS, MMSE, MADRS, appetite scale, BMI, adipose tissue content, plasma leptin and active ghrelin concentrations and serum GH, IGF-1, TSH, T3 and T4, concentrations were evaluated. Results,,, A lower plasma leptin concentration and a higher serum IGF-1 concentration were found in PD patients with weight loss. BMI and the content of adipose tissue were positively correlated with leptin concentration in all PD patients. Paradoxically, the lower BMI was, the lower plasma active ghrelin concentration was in PD patients with the weight loss. Conclusion,,, These findings confirm that changes of plasma leptin concentration occur in PD patients with loss of weight. [source] Effect of ovariectomy and ad libitum feeding on body composition, thyroid status, ghrelin and leptin plasma concentrations in female dogs,JOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1-2 2006I. Jeusette Summary The objective of this study was to evaluate the effects of ovariectomy (i) and ad libitum feeding (ii) on energy intake, body weight (BW), body composition, thyroid status, leptin and ghrelin plasma concentrations. Four young adult female Beagle dogs were fed a maintenance diet for 6 weeks prior to ovariectomy, then 6 months after. Food allowance was adjusted in order to maintain optimal BW. Then, a diet slightly higher in energy concentration was fed ad libitum for 4 months. The maintenance diet was then fed ad libitum for one additional month. The maintenance of optimal BW after ovariectomy required a significant decrease in energy allowance. No increase in fat mass was observed. Ghrelin concentration remained unchanged. During the first month of ad libitum feeding, plasma ghrelin concentration and energy intake increased, then they decreased. Mean BW, plasma leptin, thyrotropin (TSH), total triiodothyronine (TT3) and total thyroxine (TT4) concentrations significantly increased over the study. The BW increase was exclusively due to an increase in body fat. In conclusion, energy allowance should be strictly controlled in spayed female dogs. The results suggest that in dogs, thyroid hormones, leptin and ghrelin concentrations change in response to a positive energy balance in an attempt to limit weight gain. However, the significant weight gain shows that this goal was not achieved. [source] Effects of glucose and amino acids on ghrelin secretion in sheepANIMAL SCIENCE JOURNAL, Issue 2 2010Toshihisa SUGINO ABSTRACT Two experiments were conducted to elucidate the effects of post-ruminal administration of starch and casein (Exp. 1), plasma amino acids concentrations (Exp. 2), and plasma glucose and insulin concentrations (Exp. 2) on plasma ghrelin concentrations in sheep. In Exp. 1, plasma ghrelin concentrations were determined by four infusion treatments (water, cornstarch, casein and cornstarch plus casein) in four wethers. Abomasal infusion of casein increased plasma ,-amino N (AAN) concentrations. Infusion of starch or casein alone did not affect plasma ghrelin concentrations, but starch plus casein infusion increased plasma levels of ghrelin, glucose and AAN. In Exp 2, we investigated the effects of saline or amino acids on ghrelin secretion in four wethers. Two hours after the initiation of saline or amino acid infusion into the jugular vein, glucose was also continuously infused to investigate the effects of blood glucose and insulin by hyper-glycemic clump on plasma ghrelin concentrations. Infusion of amino acids alone raised plasma levels of ghrelin, but the higher plasma glucose and insulin concentrations had no effect on plasma ghrelin concentrations. These results suggest that high plasma levels of amino acids can stimulate ghrelin secretion, but glucose and insulin do not affect ghrelin secretion in sheep. [source] Leptin and ghrelin concentrations and weight loss in Parkinson's diseaseACTA NEUROLOGICA SCANDINAVICA, Issue 4 2010U. Fiszer Fiszer U, Micha,owska M, Baranowska B, Woli,ska-Witort E, Jeske W, Jethon M, Pia,cik-Gromada M, Marcinowska-Suchowierska E. Leptin and ghrelin concentrations and weight loss in Parkinson's disease. Acta Neurol Scand: 2010: 121: 230,236. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Objectives,,, To investigate the role of leptin, ghrelin, GH and IGF-1 in energy balance disturbances in Parkinson's disease (PD). Materials and methods,,, Thirty-nine patients were included: 11 PD patients with unintentional weight loss, 16 PD patients without weight loss and 12 controls. UPDRS, MMSE, MADRS, appetite scale, BMI, adipose tissue content, plasma leptin and active ghrelin concentrations and serum GH, IGF-1, TSH, T3 and T4, concentrations were evaluated. Results,,, A lower plasma leptin concentration and a higher serum IGF-1 concentration were found in PD patients with weight loss. BMI and the content of adipose tissue were positively correlated with leptin concentration in all PD patients. Paradoxically, the lower BMI was, the lower plasma active ghrelin concentration was in PD patients with the weight loss. Conclusion,,, These findings confirm that changes of plasma leptin concentration occur in PD patients with loss of weight. [source] Altered distribution of adiponectin isoforms in children with Prader,Willi syndrome (PWS): association with insulin sensitivity and circulating satiety peptide hormonesCLINICAL ENDOCRINOLOGY, Issue 6 2007Andrea M. Haqq Summary Objective, Prader,Willi syndrome (PWS) is a genetic syndrome characterized by relative hypoinsulinaemia and normal or increased insulin sensitivity despite profound obesity. We hypothesized that this increased insulin sensitivity is mediated by increased levels of total and high molecular weight adiponectin and associated with changes in levels of satiety hormones. Design, patients and measurements, We measured total adiponectin and its isoforms [high molecular weight (HMW), middle molecular weight (MMW) and low molecular weight (LMW) adiponectin] and satiety hormones in 14 children with PWS [median age 11·35 years, body mass index (BMI) Z- score 2·15] and 14 BMI-matched controls (median age 11·97 years, BMI Z- score 2·34). Results, Despite comparable BMI Z- scores and leptin levels, the PWS children exhibited lower fasting insulin and HOMA-IR (homeostasis model assessment of insulin resistance) scores compared to obese controls. For any given BMI Z- score, the PWS children showed higher concentrations of fasting total and HMW adiponectin and higher HMW/total adiponectin ratios. The HMW/total adioponectin ratio was preserved in children with PWS at high degrees of obesity. In PWS children, fasting plasma total adiponectin, HMW adiponectin and HMW/total adiponectin ratio correlated negatively with age (P < 0·05), HOMA-IR (P < 0·01), BMI Z- score (P < 0·05), insulin (P < 0·01) and leptin (P < 0·05). In addition to higher fasting ghrelin concentrations, the PWS children showed significantly higher fasting levels of total peptide YY (PYY) and gastric inhibitory polypeptide (GIP) compared to obese controls. Conclusions, Relative to controls of similar age and BMI Z- score, the PWS children had significantly higher levels of total and HMW adiponectin, and increased ratios of HMW/total adiponectin. These findings may explain in part the heightened insulin sensitivity of PWS children relative to BMI-matched controls. [source] Perioperative plasma active and total ghrelin levels are reduced in acromegaly when compared with in nonfunctioning pituitary tumours even after normalization of serum GHCLINICAL ENDOCRINOLOGY, Issue 1 2007Takakazu Kawamata Summary Objective, Ghrelin is a novel gastric peptide known to stimulate GH secretion, but the relationship between ghrelin and the GH-insulin-like growth factor (IGF)-1 axis in GH excess or deficiency is poorly understood. This study investigated dysregulation of ghrelin secretion in acromegaly and its short-term postoperative recovery. Methods, A prospective study was conducted on eight patients who underwent complete transsphenoidal resection of GH-producing pituitary adenomas (acromegaly group) and 22 for endocrinologically nonfunctioning pituitary tumours (control group). Active and total plasma ghrelin levels were measured serially before and after surgery. Results, Preoperative active and total plasma ghrelin concentrations (mean ± SD; fmol/ml) were significantly reduced in acromegalic patients when compared with those in the controls (9·6 ± 4·3 and 157·4 ± 65·6 vs. 21·8 ± 13·0 and 267·1 ± 111·4; P = 0·023 and P = 0·021, respectively). Both levels were still significantly suppressed on postoperative Day 7 in the acromegaly group when compared with those in the control group (11·7 ± 4·3 and 197·8 ± 68·9 vs. 22·5 ± 12·6 and 302·7 ± 100·0; P = 0·038 and P = 0·018, respectively). The ratios of active to total ghrelin were not significantly different between the two groups before and after operation. In acromegalic patients, active and total ghrelin levels remained significantly suppressed even after normalization of serum GH levels. Conclusions, The putative negative feedback mechanism of GH on ghrelin secretion may in part account for the low ghrelin levels observed in acromegalic patients, and the mechanism may persist even after normalization of serum GH. [source] Ghrelin does not regulate the GH response to insulin-induced hypoglycaemia in children but could be involved in the regulation of cortisol secretionCLINICAL ENDOCRINOLOGY, Issue 1 2007J. Huber Summary Objective, Ghrelin activates the growth hormone secretagogue receptor GHS-R. It strongly stimulates GH secretion and has a role in energy homeostasis. The relationship between plasma ghrelin and cortisol levels during insulin-induced hypoglycaemia in prepubertal and pubertal children has not yet been investigated. The aim of the present study was to establish whether insulin-induced hypoglycaemia stimulates ghrelin secretion and whether changes in ghrelin concentrations are related to changes in GH and cortisol in children. Design and patients, We studied a group of 20 children and adolescents (five girls, 15 boys, mean age 10·8 ± 3·7 years) undergoing insulin tolerance tests (ITTs) for clinical investigation of GH deficiency. Measurements, Stimulation tests were performed to investigate the relationship between ghrelin, GH, cortisol and glucose levels according to age and pubertal stage by determining the ghrelin profiles during insulin-induced hypoglycaemia (at 0, 60 and 120 min). Results, Ghrelin was significantly and inversely related to body weight, height, body mass index (BMI) and age of children (P < 0·05). Significant changes in ghrelin levels (P = 0·00013) were found after the insulin bolus, with a decline at 60 min and an increase to baseline values at 120 min. Changes in cortisol levels were negatively correlated with changes in ghrelin at 60 min (r = ,0·59, P = 0·004) and at 120 min (r = ,0·605, P = 0·003). Conclusions, This study shows that ghrelin might not regulate the GH response to insulin-induced hypoglycaemia in prepubertal and pubertal children. A role for ghrelin in the regulation of cortisol secretion can be hypothesized concerning the negative correlation between changes in ghrelin and cortisol. Furthermore, the results imply that ghrelin secretion is age dependent and is a function of growth. [source] Serum ghrelin concentrations in patients with chronic renal failure undergoing dialysisCLINICAL ENDOCRINOLOGY, Issue 1 2006Pedro Iglesias Summary Background, ,Ghrelin is a recently discovered protein hormone mainly synthesized in the gastric endocrine cells. This hormone not only is a potent growth hormone secretagogue but also is involved in the regulation of food ingestion and energy metabolism. Derangements in ghrelin secretion in patients with chronic renal failure (CRF) have not been fully evaluated. Objective, ,Our aim has been to quantify serum concentrations of total ghrelin in a group of patients with CRF on chronic therapy with both haemodialysis (HD) and peritoneal dialysis (PD) in comparison with a group of patients on conservative management (predialysis). Patients and measurements, ,We studied 68 CRF patients treated by HD (n = 30, 16 men, age 61·2 ± 1·8 years) and PD groups (n = 38, 21 men, age 54·4 ± 1·7 years). A group of 19 uraemic patients on conservative management served as the control. Serum concentrations of ghrelin, leptin, insulin, IGF I and GH were measured in all subjects. Results, ,Patients undergoing HD showed similar concentrations of ghrelin in comparison with the control group (9491 ± 787 vs 9280 ± 918 pg/ml, NS). However, PD patients exhibited baseline ghrelin concentrations significantly lower than those found in patients on conservative management (3230 ± 216 pg/ml, P < 0·0001). Men and women showed similar serum ghrelin levels in both HD (9845·9 ± 1071 vs 9085 ± 1194 pg/ml) and PD patients (3214 ± 297 vs 3250 ± 324 pg/ml). Hypertension and diabetes mellitus did not influence ghrelin levels. Serum GH levels were positively correlated with serum ghrelin concentrations in both HD (r = 0·46, P < 0·05) and PD (r = 0·53, P < 0·001) patients; however, no relationships between ghrelin, leptin, insulin and IGF I were found. Conclusions, ,These results suggest that PD is accompanied by a striking decrement in baseline ghrelin concentrations in comparison with values found both in HD and control patients. Further studies are necessary to determine mechanisms involved in ghrelin regulation in uraemic patients. [source] |