Obestatin Concentrations Research Articles

Helicobacter pylori infection and serum leptin, obestatin, and ghrelin levels in Mexican schoolchildren.

BackgroundThere is little information about the possible role of Helicobacter pylori infection on appetite-regulating peptides in children. This study evaluated the association between H. pylori infection and serum levels of ghrelin, leptin, and obestatin in schoolchildren.MethodsOne hundred seventy-eight schoolchildren, students at boarding schools in Mexico City, participated. H. pylori infection status was determined every 6 months for 1 year by a breath test using 13C-urea; schoolchildren with consistently positive or negative results were selected to participate. Age, sex, and body mass index (BMI) were recorded. Serum concentrations of total ghrelin, leptin, and obestatin via specific enzyme-linked immunosorbent assays were determined.ResultsSchoolchildren with H. pylori infection had lower concentration of leptin, -0.54 pg/ml (95% CI: -0.98 to -0.09), compared to the schoolchildren without infection, after adjustment by age, gender, and BMI. And the children with the infection had a median of obestatin lower in 0.99 ng/ml (95% CI: -1.93 to -0.06) compared with the uninfected children after adjustment by BMI.ConclusionAssociation was found between H. pylori infection and decreased serum concentrations of leptin and obestatin. These results suggest that in schoolchildren, H. pylori infection affects the levels of hormones implicated in regulating appetite and energy homeostasis.

Obestatin Plays Beneficial Role in Cardiomyocyte Injury Induced by Ischemia-Reperfusion In Vivo and In Vitro.

BackgroundObestatin, primarily recognized as a peptide within the gastrointestinal system, has been shown to benefit the cardiovascular system. We designed this experiment to study the protective role and underlying mechanism of obestatin against ischemia-reperfusion(I/R) injury in myocardial cells.Material/MethodsIn an In vivo experiment, LAD was ligated for 0.5 h and then opened for reperfusion with obestatin for 24 h. Then, the infarction area was shown with TTC staining, and inflammation factors in serum were analyzed by qRT-PCR. In primary cultured cardiomyocytes, we measured the level of LDH, MDA, GSH, and SOD. Finally, we assessed cells apoptosis using flow cytometry and detected the concentrations of caspase-3, Bax, and Bcl-2 using Western blot analysis.ResultsTTC staining showed that in the 3 obestatin groups, the infarct area became smaller with the increase of obestatin concentration. Obestatin also inhibited LDH expression in rat serum and decreased mRNA levels of TNF-α, IL-6, ICAM-1, and iNOS in rat cardiomyocytes after reperfusion. In primary cultured cardiomyocytes, obestatin decreased LDH content and increased GSH level after I/R injury. Obestatin was also found to antagonize the apoptosis of cardiomyocytes in a dose-dependent manner. Western blot analysis showed that obestatin downregulated the expression of caspase-3 and Bax and upregulated the expression of Bcl-2.ConclusionsObestatin can protect cardiomyocyte from I/R-induced injury in vitro and in vivo. This beneficial effect is closely related with its properties of anti-inflammation, anti-cytotoxicity, and anti-apoptosis. The protective effect of obestatin might be associated with activation of Bcl-2 and inhibition of caspase-3 and Bax.

The obestatin/ghrelin ratio and ghrelin genetics in adult celiac patients before and after a gluten-free diet, in irritable bowel syndrome patients and healthy individuals.

Ghrelin levels and obestatin/ghrelin ratio have been proposed as activity markers in ulcerative colitis, but no data are available in celiac disease (CD) and irritable bowel syndrome (IBS). Our aims were as follows: (a) to assess obestatin and ghrelin concentrations in adult active CD patients, diarrhea-predominant IBS (IBS-d), and healthy controls (HC) in relation to intestinal permeability; (b) to evaluate the ghrelin-obestatin profile in CD patients after a 1-year gluten-free diet (GFD); and (c) to establish the impact of ghrelin genetics. The study included 31 CD patients, 28 IBS-d patients, and 19 HC. Intestinal permeability, assayed by high-performance liquid chromatography determination of urinary lactulose (La)/mannitol (Ma), and circulating concentrations of obestatin, ghrelin, and their ratio were evaluated at enrollment and after GFD. The ghrelin single nucleotide polymorphisms Arg51Gln (rs34911341), Leu72Met (rs696217), and Gln90Leu (rs4684677) were analyzed. Intestinal permeability was impaired in CD patients and ameliorated after GFD. Ghrelin was significantly (P=0.048) higher and the obestatin/ghrelin ratio was significantly (P=0.034) lower in CD patients compared with both IBS-d and HC, and GFD reduced the peptide levels, but without reaching the concentrations in HC. Significant differences (P<0.05) were found in the Leu72Met polymorphism among groups, with the reduction of the GT genotype and the T allele in both CD and IBS-d patients compared with HC. Intestinal permeability is altered in CD, but not in IBS-d patients, and ghrelin levels increase in CD patients as observed in other inflammatory conditions. Moreover, a role for ghrelin genetics is hypothesized in sustaining the many pathogenetic components of these different pathologies, but with a similar symptom profile.

Concentrations of prealbumin and some appetite-controlling hormones in pregnancies associated with hyperemesis gravidarium.

Background Hyperemesis gravidarum, which affects 0.3-2.3% of pregnancies, is defined as excessive vomiting during pregnancy and usually starts in week 4 or 5 of gestation. Symptoms include weight loss, dehydration, ketonaemia, ketonuria, fasting acidosis, alkalosis due to hydrochloric acid loss and hypokalaemia and its exact cause is unknown. The present study was undertaken to investigate the relationship between prealbumin, ghrelin, nesfatin-1 and obestatin concentrations in pregnancies associated with hyperemesis gravidarum. Methods A total of 40 pregnant females with hyperemesis gravidarum and 38 pregnant females without hyperemesis gravidarum as controls were included in this study. Serum concentrations of prealbumin, ghrelin, obestatin and nesfatin-1 were measured. Results There were no significant differences in age, gestational week, gravidity and parity between the two groups. Body mass index was significantly lower in cases than in controls. Serum ghrelin and prealbumin concentrations were significantly lower in cases than in controls ( P <0.05 and P < 0.001, respectively). There was no significant difference in serum concentrations of obestatin and nesfatin-1 between the two groups. There was no significant association between body mass index and serum ghrelin, nesfatin-1, obestatin or prealbumin concentrations in patients with hyperemesis gravidarum. Conclusions Decreased serum concentrations of ghrelin and prealbumin in patients with hyperemesis gravidarum are independent of body mass index. Based on our results, we believe that ghrelin may be considered to play a role in the aetiopathogenesis of hyperemesis gravidarum and that hyperemesis gravidarum may result in disruption of the relationship between nesfatin-1 and ghrelin. In addition, we believe that the measurement of serum prealbumin may be used for assessing nutritional status in pregnancy.

OP.7B.09] CHEMERIN AND BLOOD PRESSURE AND METABOLIC SYNDROME IN POSTMENOPAUSAL WOMEN

Objective: Chemerin is recently identified adipose hormone, which plays a role in adipogenesis, energy metabolism and inflammation. Increased levels of chemerin have been linked to obesity and development of diabetes mellitus. During the transition from premenopause to postmenopause, many women experience weight gain and central fat deposition, hence we hypothesized that circulating level of chemerin can play a role in the pathogenesis of hypertension and cardiometabolic risk in postmenopausal females. Design and method: Methods: The study included 80 women (mean age 57.6 ± 5.4 years), 54 subjects with arterial hypertension and 26 normotensive age matched controls. In all subjects anthropometrical measurements and 24-hr ABPM were performed. Fasting blood samples were taken for glucose, insulin and serum lipids concentration. Serum levels of chemerin, nesfatin and obestatin were measured using an immunochemical assay. Asymptomatic organ damages were analyzed including echocardiographic examination with assessment of left ventricular mass (LVM), (GE Vivid 7.0); carotid ultrasound with measurement of intima-media thickness (IMT), and carotid-femoral pulse wave velocity measurement(PWV) (Sphygmocor). Results: Results: Compared with controls, subjects with hypertension had higher serum chemerin levels (147,8 ± 29,7 vs 132,2 ± 23,6; p = 0,05). Nesfatin and obestatin concentrations did not differ between hypertensive and normotensive groups. Chemerin was significantly associated with metabolic characteristics including BMI (r = 0,32, p = 0,003), waist circumference (r = 0,48, p = 0,0001), fasting glucose (r = 0,27, p = 0,02), and triglycerides (r = 0,20, p = 0.07). In logistic regression analysis, chemerin concentration was an independent predictor of the presence of hypertension, but the association lost its significance after adjustment for BMI. Conclusions: Conclusions: In postmenopausal women serum chemerin is independently associated with left ventricular mass, left atrial volume and components of metabolic syndrome. Association of chemerin with hypertension is mediated by body adiposity.

Changes in obestatin gene and GPR39 receptor expression in peripheral tissues of rat models of obesity, type 1 and type 2 diabetes.

Obestatin has a role in regulating food intake and energy expenditure, but the roles of obestatin and the GPR39 receptor in obesity and type 1 and type 2 diabetes mellitus (T1DM and T2DM, respectively) are not well understood. The aim of the present study was to investigate changes in obestatin and GPR39 in pathophysiological conditions like obesity, T1DM, and T2DM. Using rat models of diet-induced obesity (DIO), T1DM and T2DM (n = 14 per group), obestatin, its precursor protein preproghrelin, and GPR39 expression was investigated in tissues involved in glucose and lipid homeostasis regulation. Furthermore, serum obestatin and ghrelin concentrations were determined. Serum obestatin concentrations were positively correlated with glucagon (r = 0.6456; P <0.001) and visfatin (r = 0.5560; P <0.001), and negatively correlated with insulin (r = -0.4362; P <0.05), adiponectin (r = -0.3998; P <0.05), and leptin (r = -0.4180; P <0.05). There were differences in GPR39 and preproghrelin expression in the three animal models. Hepatic GPR39 and preproghrelin mRNA expression was greater in T1DM, T2DM, and obese rats than in lean controls, whereas pancreatic GPR39 mRNA and protein and preproghrelin mRNA expression was decreased in T1DM, T2DM, and DIO rats. Higher GPR39 and preproghrelin protein and mRNA levels were found in adipose tissues of T1DM compared with control. In adipose tissues of T2DM and DIO rats, GPR39 protein levels were lower than in lean or T1DM rats. Preproghrelin mRNA was higher in adipose tissues of T1DM, T2DM, and DIO than lean rats. We hypothesize that changes in obestatin, GPR39, and ghrelin may contribute to metabolic abnormalities in T1DM, T2DM, and obesity.

Studies on the influence of CCK-8 on the ability of obestatin to reduce food intake, gain in body weight and related lipid parameters.

In an effort to mimic in part the redundancy of satiety peptides involved in energy homeostasis, the combined benefits of the well-established satiety peptide CCK8 and an apparently anorectic peptide obestatin were studied in Swiss albino mice. The optimal dose of obestatin that was required to give the most pronounced effect with CCK8 was worked out by varying the concentration of obestatin while keeping CCK8 concentration constant at 200nmol/KgBW. Mice administered 160nmol obestatin and 200nmol CCK8 per kilogram body weight showed the most drastic reduction in food intake. Gain in body weight was arrested after day four during the eight day experiment. These studies reemphasize the beneficial effects imparted by co-administration of obestatin and CCK8 and their potential use towards countering obesity.

Maternal High-Fat Diet during Pregnancy and Lactation Influences Obestatin and Ghrelin Concentrations in Milk and Plasma of Wistar Rat Dams and Their Offspring.

The study aims to establish the effect of a maternal high-fat diet on obestatin concentration, total ghrelin, and ghrelin/obestatin ratio during pregnancy and lactation of Wistar rats and their offspring in the first 21 days of life. On the mating day, females were randomly allocated and fed either a high-fat diet (30% of fat; HF) or breeding diet (5% fat; BD) till the 21st day of lactation. Hormones were analyzed in the blood plasma and milk of rat dams as well as in the blood plasma of their offspring. HF resulted in a significant decrease in obestatin level on the 14th day of lactation and elevation on the 21st day. Plasma obestatin in HFD offspring was significantly higher than in BD ones. HF diet did not significantly affect dam plasma ghrelin until the 21st day of lactation. The ghrelin concentrations in milk after both diets were significantly lower than in blood plasma. Milk ghrelin in HF dams was significantly higher than in the BD ones. Plasma ghrelin from HF offspring was significantly higher than that from BD dams. Our results demonstrate that a maternal HF diet during pregnancy and lactation influences ghrelin and obestatin level in both dams and their offspring.

Assessment of Serum Concentrations of Ghrelin, Obestatin, Omentin-1, and Apelin in Children with Type 1 Diabetes.

The increasing knowledge on the functions of gastric peptides and adipokines in the body allows the assumption of their major role linking the process of food intake, nutritional status, and body growth, largely through the regulation of glucose metabolism and insulin resistance. The aim of the study was the assessment of serum levels of selected gastric peptides and adipocytokines in children with type 1 diabetes, with respect to the disease duration. The study involved 80 children aged 4–18 years (M/F -37/43). Children with type 1 diabetes (n = 46) were compared to the control group (n = 34). The study group was divided into 4 subgroups: (I) patients with newly diagnosed type 1 diabetes, after an episode of ketoacidosis (n = 10), (II) patients with type 1 diabetes of duration no longer than 5 years (n = 9), (III) patients with 5 to 10 years of DT1 (n = 20), and (IV) patients with type 1 diabetes of duration longer than 10 years (n = 7). The concentrations of gastric peptide and adipocytokines across all subgroups were lower than in the control group. The differences were statistically significant (p < 0.0001), which may be of importance in the development of the disease complications.

The role of obestatin in roux-en-Y gastric bypass-induced remission of type 2 diabetes mellitus.

Type 2 diabetes mellitus (T2DM) is a complex and multifactorial disease that is generally characterized by insulin resistance and loss of β-cell function that develops in adulthood. To date, more than 6% of the world's population is affected by T2DM. The main treatments of T2DM are dietary and lifestyle changes. However, only dependent on behaviour modification and oral hypoglycemics, many patients are unable to maintain glycemic control. Emerging evidence indicates that up to 80% of patients with T2DM undergoing Roux-en-Y gastric bypass (RYGB) experience complete remission of their T2DM and the majority of remissions occur almost immediately following the operation. Obestatin is a 23-amino-acid peptide, which is not only thought to suppress food intake and decrease gastric emptying but also found to exert survival effects in pancreatic β cells, increase glucose-stimulated insulin secretion, and reduce insulin resistance and inflammation. In addition, some researchers demonstrated that obestatin is a nutritional marker reflecting body adiposity and insulin resistance. Although results from previous studies were conflicting, the peripheral blood concentrations of obestatin were changed after RYGB. Therefore, regulation of obestatin level may be another mechanism for RYGB-induced remission of T2DM. In this article, we review briefly the effect of RYGB on T2DM in humans and offer an overview of the published data on the effects of RYGB on obestatin level in patients with T2DM. Furthermore, the possible roles of obestatin in the remission of T2DM following RYGB are also reviewed. Copyright © 2015 John Wiley & Sons, Ltd.

Maternal serum ratio of ghrelin to obestatin decreased in preeclampsia.

Ghrelin, an endogenous for the growth hormone secretagogue receptor, has been shown to participate in blood pressure regulation. Obestatin, encoded by the same gene as ghrelin, is described as a physiological opponent of ghrelin. We hypothesized that ghrelin/obestatin imbalance played a role in the pathogenesis. This study was designed to determine the alterations of ghrelin and obestatin concentrations and ghrelin/obestatin ratio in maternal serum in preeclampsia. This retrospective case-control study included 31 preeclampsia and 31 gestational week-matched normal pregnancies. Ghrelin and obestatin concentrations in maternal serum were determined by radioimmunoassay, and the ghrelin/obestatin ratio was calculated. The ghrelin concentration and ghrelin/obestatin ratio in maternal serum were significantly lower in preeclampsia than in normal pregnancies (214.34±14.27pg/mL vs 251.49±16.15pg/mL, P=0.041, 1.07±0.09 vs 0.82±0.08, P=0.023). The obestatin concentration in maternal serum was significantly higher in preeclampsia than in normal pregnancies (276.35±15.38pg/mL vs 223.53±18.61pg/mL, P=0.019). The systolic blood pressure in preeclampsia was negatively correlated with ghrelin concentration and ghrelin/obestatin ratio (r=-0.549, P=0.003; r=-0.491, P=0.004) and was positively correlated with obestatin concentrations in preeclampsia (r=0.388, P=0.013). The findings of this study suggested disturbance of ghrelin and obestatin in maternal serum in preeclampsia, and ghrelin/obestatin imbalance might play a role in the pathogenesis of preeclampsia.

The study of ghrelin and obestatin system in patients with essential hypertension

Objective To measure the fasting plasma ghrelin and obestatin concentrations in essential hypertension(EH) patients with obesity,and to observe their relationship with blood pressure,obesity index, insulin resistance(IR),blood glucose and blood lipid. Methods 68 hypertensive obese patients,60 normotensive obese patients and 65 healthy controls were included in the study.The fasting plasma obestatin and ghrelin were measured using a radioimmunoassay method.The ghrelin/obestatin ratio was calculated. Results Hypertensive obese patients had lower plasma ghrelin and obestatin compared with normotensive obese patients(t= 3.771,P< 0.01;t= 4.373,P< 0.01）and controls(t= 16.451,P< 0.01;t= 17.862,P< 0.01）。Normotensive obese patients had lower plasma ghrelin and obestatin compared with controls(t= 13.121,P< 0.01;t= 13.686,P< 0.01）。Hypertensive obese patients had higher ghrelin/obestatin ratio than controls(t= 7.720,P< 0.01）。The ghrelin/obestatin ratio in normotensive obese patients was higher than controls(t= 4.587,P< 0.01）。In hypertensive obese group,the plasma ghrelin and obestatin were negatively associated with BMI(r=-0.882,P< 0.01;r=-0.806,P< 0.01），SBP(r=-0.787,P< 0.01;r=-0.837,P< 0.01），DBP(r= -0.769,P< 0.01;r=-0.810,P< 0.01），and the HOMA-IR(r=-0.800,P< 0.01;r=-0.810,P< 0.01）。In normotensive obese group,ghrelin and obestatin were all negatively associated with BMI(r=-0.577,P< 0.01;r=-0.372,P< 0.01） and HOMA-IR(r=-0.866,P< 0.01;r=-0.662,P< 0.01）。 The ghrelin/obestatin ratio was positively associated with BMI(r= 0.460,P< 0.01） and HOMA-IR(r= 0.420,P< 0.01）。 Conclusion The peripheral blood ghrelin,obestatin and ghrelin/obestatin ratio were significantly correlated with EH,obesity and IR.No correlation was observed between ghrelin/obestatin system and blood lipid or blood glucose. Key words: Hypertension; Obesity; Insulin resistance; Ghrelin; Obestatin

Plasma Ghrelin Concentrations Are Negatively Correlated With Urine Albumin-to-Creatinine Ratio in Newly Diagnosed Type 2 Diabetes

BackgroundAging is associated with a decrease in appetite, energy intake and glucose tolerance. Experimental studies have suggested that ghrelin and obestatin play a role in glucose homeostasis and in the regulation of energy metabolism. However, few studies have been performed on the role of ghrelin and obestatin in middle-aged and old adults. MethodsIn the present study, we investigated the plasma concentrations of ghrelin and obestatin in middle-aged (41-64 years) and old (65-76 years) subjects with newly diagnosed type 2 diabetes mellitus (NDD) and normal glucose tolerance (NGT). We also characterized the relationship among plasma ghrelin and obestatin levels and glucose/lipid metabolism. The fasting plasma ghrelin and obestatin concentrations were analyzed using enzyme immunoassay method. ResultsPlasma obestatin concentrations in diabetic subjects were significantly lower than those in NGT subjects. Plasma ghrelin were negatively associated with fasting glucose, hemoglobin A1c, urine albumin-to-creatinine ratio (UACR) and positively correlated with high-density lipoprotein cholesterol. In addition, plasma obestatin level was correlated negatively with systolic blood pressure, triglycerides and total cholesterol. Furthermore, multiple regression analysis indicated that UACR was a significantly independent predictor of fasting plasma ghrelin levels. ConclusionsCollectively, ghrelin and obestatin levels may be markers reflecting glucose and lipid conditions in NDD. The lower ghrelin levels may be a potential indicator for renal dysfunction in patients with type 2 diabetes mellitus.

Ghrelin and obestatin levels in hypertensive obese patients.

To investigate plasma total ghrelin and obestatin levels and the ghrelin/obestatin ratio prospectively, in hypertensive obese patients. Height, weight, and waist and hip circumferences were measured in hypertensive and normotensive obese patients and matched healthy controls; the body mass index and waist to hip ratio were calculated. Fasting glucose and insulin levels were measured and the homeostasis model assessment of insulin resistance (HOMA-IR) was determined. Fasting ghrelin and obestatin concentrations were measured by radioimmunoassay and the ghrelin/obestatin ratio was calculated. A total of 38 hypertensive obese patients, 40 normotensive obese patients and 38 controls were enrolled. Hypertensive obese patients had lower plasma levels of ghrelin and obestatin than normotensive obese patients or controls. In addition, normotensive obese patients had lower plasma ghrelin and obestatin levels than controls. In hypertensive obese patients, ghrelin and obestatin levels were negatively associated with systolic and diastolic blood pressure, fasting insulin and HOMA-IR. In normotensive obese patients, ghrelin, obestatin and the ghrelin/obestatin ratio were negatively associated with fasting insulin and HOMA-IR. In both patient groups, fasting obestatin and ghrelin concentrations were significantly and positively correlated with each other. Changes in the levels of ghrelin and obestatin may play a role in the pathophysiology of obesity and hypertension.

A possible association between circulating concentrations of obestatin, LH, FSH, testosterone and inhibin B during puberty in normal healthy boys

A possible association between circulating concentrations of obestatin, LH, FSH, testosterone and inhibin B during puberty in normal healthy boys

Effects of plasma ghrelin, obestatin, and ghrelin/obestatin ratio on blood pressure circadian rhythms in patients with obstructive sleep apnea syndrome.

Obstructive sleep apnea syndrome (OSAS) is strongly associated with obesity and with cardiovascular disease. Ghrelin and obestatin are two peptides from the same source but have opposite roles. Both of them can affect feeding and regulate vascular tune. The aim of this study was to investigate the relationship between plasma ghrelin, obestatin, the ratio of ghrelin and obestatin (G/O) and sleep parameters and blood pressure circadian rhythms in patients with OSAS. This study enrolled 95 newly diagnosed over-weight OSAS patients (OSAS group), 30 body mass index (BMI)-match non-OSAS adults (over-weight group) and 30 non-OSAS normal weight adults (control group). Polysomnography (PSG) was performed in the OSAS group and over-weight group. Blood pressure of all subjects was monitored by means of 24-hour ambulatory blood pressure monitoring. The concentration of plasma ghrelin and obestatin was detected by enzyme-linked immunosorbent assay (ELISA). Plasma ghrelin levels in the OSAS group and over-weight group were significantly lower than that of the control group (P < 0.05). Plasma obestatin levels were lower in the over-weight group and OSAS group, but there was no significant difference among the three groups. The blood pressure in OSAS patients was higher, and there was a significant difference in all blood pressure parameters compared to the control group, and in the daytime average diastolic blood pressure (DBP), nocturnal average systolic blood pressure (SBP) and DBP, DBP variability values as compared to over-weight subjects. Furthermore, there were significantly more non-dipper patterns of blood pressure (including hypertension and normotension) in the OSAS group than in the other two groups (P < 0.01). Correlation analysis showed that ghrelin levels had a significant correlation with BMI and nocturnal average DBP but not with PSG parameters. In contrast, the G/O ratio had a negative correlation with apnea-hypopnea index (AHI) (P < 0.05), as well as a strong positive correlation with the blood pressure variability values (P < 0.01). In multivariate analyses, AHI (P < 0.05) and G/O (P < 0.05) were independently related to SBP variability changes, while AHI (P < 0.05), G/O (P < 0.01) and BMI (P < 0.05) were independently related to DBP variability changes. Our data show plasma ghrelin and obestatin levels were related to obesity in OSAS. Sleep apnea in OSAS patients could have led to an imbalance in G/O in the basis of obesity. Moreover, the imbalance may promote nighttime blood pressure elevation and affect blood pressure circadian disorder.

The Effect of Isolated Obestatin Hormone from Plasma on some Biochemical Parameters in Normal and Diabetic Rats

The study included an attempt to isolate and purify obestatin from healthy human plasma using different biochemical techniques. Two proteinous peaks had been isolated by gel filtration chromatography (Sephadex G-50) from the precipitate produced by precipitation using cold acetone. It was found that the second peak (peak B) only had an obestatin. Two proteinous components had also been isolated by the same technique using Sephadex G-25 from the peak B. It was found that the second peak (peak D) had a high concentration of obestatin . Furthermore, the purity of the isolated obestatin (peak D) had been identified by the reversed phase high performance liquid chromatography and by SDS-polyacrylamide gel electrophoresis technique. The results obtained from the RP-HPLC showed that there was a good identity in retention time between the standard and the isolated obestatin (peak D). The approximate molecular weight of partially purified obestatin was (2573 ± 100 Da) and (2660 Da) using gel filtration chromatography by Sephadex G-25 and ( SDS-PAGE) technique respectively. The effect of the isolated obestatin (peak D) on some biochemical parameters in normal and alloxan induced diabetic male rats had been studied. After one week of treatment, the results showed that the obestatin at the dose (1 µmol / kg of body weight / d) caused a significant decrease in the levels of glucose, total lipids, total cholesterol, triglycerides, LDL-C, VLDL-C and MDA, in a addition to a significant increase in the levels of HDL-C in normal and alloxan induced diabetic rats and GSH in alloxan induced diabetic rats. It was concluded that the isolated obestatin from plasma had a an important role in metabolism of glucose and lipid profile in normal and alloxan induced diabetic rats.

Differential Influences of Gastric Bypass and Sleeve Gastrectomy on Plasma Nesfatin-1 and Obestatin Levels in Patients with Type 2 Diabetes Mellitus

The mechanisms by which bariatric surgeries, including gastric bypass (GB) and sleeve gastrectomy (SG), achieve remission of type 2 diabetes mellitus (T2DM) and sustained weight reduction are unknown. We hypothesized that the novel anorexic hormone nesfatin-1 and another new hormone obestatin might contribute to the marked improvement in glycemic homeostasis and weight loss in diabetics after GB and SG. A hospital-based, prospective study was conducted. Overnight fasting plasma concentrations of nesfatin-1 and obestatin were analyzed in T2DM patients before surgery, and at 3 and 12 months after laparoscopic GB (n =12) and SG (n = 6). At 12 months, reductions of body mass index (BMI), fasting blood glucose, and glycated hemoglobin were similar between GB and SG groups (P all > 0.05). Plasma nesfatin-1 levels in patients undergoing GB or SG significantly decreased after surgeries (P both < 0.05). In contrast, plasma obestatin concentrations significantly increased in patients after SG (P < 0.05) but without any alteration after GB. The alterations of plasma nesfatin-1 were significantly and negatively associated with the reduction of fasting blood glucose (P <0.05) at 12 months after GB and SG. In the SG group, the reduction of nesfatin-1 significantly and positively correlated with the decrease of BMI (P < 0.05). GB and SG produce differential influences with regards to circulating nesfatin-1 and obestatin levels in non-morbidly obese, T2DM patients. Circulating nesfatin-1 may modulate glucose homeostasis in two surgical procedures, and participate in regulating body weight in SG.

Effect of Chronic Exercise on Appetite Control in Overweight and Obese Individuals

The effect of exercise on body mass is likely to be partially mediated through changes in appetite control. However, no studies have examined the effect of chronic exercise on obestatin and cholecystokinin (CCK) plasma concentrations or the sensitivity to detect differences in preload energy in obese individuals. The objective of this study was to investigate the effects of chronic exercise on 1) fasting and postprandial plasma concentrations of obestatin, CCK, leptin, and glucose insulinotropic peptide (GIP) and 2) the accuracy of energy compensation in response to covert preload manipulation. This study used a 12-wk supervised exercise program in 22 sedentary overweight/obese individuals. Fasting/postprandial plasma concentrations of obestatin, CCK, leptin, and GIP were assessed before and after the intervention. Energy compensation at a 30-min test meal after a high-energy (607 kcal) or a low-energy (246 kcal) preload and for the rest of the day (cumulative energy intake [EI]) was also measured. There was a significant reduction in the plasma concentration of fasting plasma GIP and both fasting and postprandial leptin concentrations after the exercise intervention (P < 0.05 for all). No significant changes were observed for CCK or obestatin. A significant preload-exercise interaction (P = 0.011) was observed on cumulative EI and energy compensation for the same period (-87% ± 196% vs 68% ± 165%, P = 0.011). Weight loss (3.5 ± 1.4 kg, P < 0.0001) was not correlated with changes in energy compensation. This study suggests that exercise improves the accuracy of compensation for previous EI, independent of weight loss. Unexpectedly, and in contrast to GIP and leptin, exercise-induced weight loss had no effect on obestatin or CCK concentrations.

Obestatin is associated to muscle strength, functional capacity and cognitive status in old women

Obestatin has been proposed to have anorexigenic and anti-ghrelin actions. The objective was to study obestatin concentrations in relation to handgrip strength, functional capacity and cognitive state in old women. The prospective study included 110 women (age, 76.93 ± 6.32) from the Mataró Ageing Study. Individuals were characterized by anthropometric variables, grip strength, Barthel and assessment of cognitive impairment [Mini Cognoscitive Examination (MCE) Spanish version], depressive status by the Geriatric Depression Scale (GDS) and frailty by the Fried criteria. Obestatin was measured by IRMA. Obestatin showed negative correlation to handgrip at basal time point (r = -0.220, p = 0.023) and at 2-year follow-up (r = -0.344, p = 0.002). Obestatin, divided into quartiles, showed a negative lineal association with handgrip: 11.03 ± 4.88 kg in first, 8.75 ± 4.08 kg in second, 8.11 ± 3.66 kg in third and 7.61 ± 4.08 kg in fourth quartile (p = 0.018). Higher obestatin levels were associated to increased weakness (categorized by handgrip of frailty criteria): 2.24 ± 0.42 ng/ml in weak vs. 1.87 ± 0.57 ng/ml in non-weak (p = 0.01). The decrease of either MCE or Barthel scores at 2-year follow-up was significantly higher in individuals in the fourth quartile of obestatin in comparison with individuals in the first quartile (p = 0.046 and p = 0.019, respectively). No association was found between obestatin and GDS score and neither with frailty as a condition. Obestatin is associated to low muscle strength, and impaired functional and cognitive capacity in old women participating in the Mataró Ageing Study.