Relationship between metabolic syndrome and acylated/desacylated ghrelin ratio in patients with schizophrenia under olanzapine medication

Background: Ghrelin is a peptide hormone that mediates glucose homeostasis and lipid metabolism. Acylated ghrelin (AG) and desacylated ghrelin (DAG) are the two main forms of ghrelin, which have opposing roles in energy homeostasis. The AG/DAG ratio has been proposed to be associated with metabolic syndrome (MetS) in the general population. This study compared the relationships between MetS and ghrelin parameters in patients with schizophrenia. Methods: Patients diagnosed with schizophrenia and under olanzapine monotherapy were recruited. Fasting blood samples were collected for the analyses of metabolic and ghrelin parameters. The serum levels of total ghrelin and AG were measured by enzyme-linked immunosorbent assay kits. DAG level was calculated by subtracting the AG level from the total ghrelin level. Results: We recruited 151 subjects with schizophrenia, and classified them into those with MetS ( n = 41) and those without MetS ( n = 110). Subjects with MetS had a significantly higher AG/DAG ratio, as well as lower total ghrelin and DAG levels. There were no sex differences in ghrelin parameters. The AG/DAG ratio was significantly and positively correlated with weight, body mass index, waist circumference, insulin level, homeostasis model assessment of insulin resistance and number of MetS components. Multiple linear regression analysis indicated that the number of MetS components remained significantly associated with the AG/DAG ratio. Conclusions: Our results revealed that lower AG/DAG ratios were associated with better metabolic profiles in olanzapine-treated patients with schizophrenia. These observations suggest that the balance between AG and DAG plays a crucial role in the metabolic homeostasis among patients with schizophrenia.

Acylated and Desacylated Ghrelin, Preptin, Leptin, and Nesfatin-1 Peptide Changes Related to the Body Mass Index

This study examines the levels of acylated and desacylated ghrelin, preptin, leptin, and nesfatin-1 peptide changes related to the body mass index (BMI). The subjects were allocated to 5 groups depending on their BMIs as follows: Group I (BMI <18.5 kg/m2); Group II (BMI 18.5–24.9 kg/m2); Group III (BMI 25–29.9 kg/m2); Group IV (BMI 30–39.9 kg/m2); Group V (BMI >40 kg/m2). Serum acylated and desacylated ghrelin, preptin, and leptin levels were measured by the enzyme-linked immunosorbent assay (ELISA) and nesfatin-1 was measured by the enzyme immunoassay (EIA). Desacylated ghrelin levels showed a gradual and statistically significant drop from Group I to Group V, while preptin and leptin levels exhibited a gradual and significant increase from Group I to Group IV. Serum nesfatin-1 levels gradually, but not significantly, increased from Group I to Group III and showed a significant decrease in Groups IV and V. In conclusion, leptin, preptin, and acylated ghrelin (AG) levels increased with higher BMI, whereas desacylated ghrelin (DAG) decreased and nesfatin-1 showed no clear relationship to BMI.

Effects of Sodium Octanoate, Acylated Ghrelin, and Desacylated Ghrelin on the Growth of Genetically Engineered Escherichia Coli

Effects of Sodium Octanoate, Acylated Ghrelin, and Desacylated Ghrelin on the Growth of Genetically EngineeredEscherichia ColiAcylated ghrelin is a 28-amino acid peptide hormone bearing a fatty acid group based on octanoic acid (caprylic acid) at the serine which is located at position 3 and at the N-terminus. If this fatty acid is cleaved from acylated ghrelin, the remaining peptide is referred to as desacylated ghrelin. Free fatty acids (FFAs) can kill or inhibit the growth of bacteria. The purpose of this study was to test this ability using acylated ghrelin, desacylated ghrelin, and sodium octanoate (caprylic acid) as carbon sources for the genetically engineeredEscherichia colistrains MK79 and MK57. For this experimental work, minimal medium was modified by replacing glucose with equal concentrations of acylated ghrelin, desacylated ghrelin, or sodium octanoate. Bacterial optical density, viability, alpha-amylase production, plasmid stability and pH of the growth medium were measured during these experiments. The media that allowed most growth, based on viable cell counts and the OD600of MK79, was minimal medium, followed by the medium containing desacylated ghrelin or acylated ghrelin, and finally the medium containing sodium octanoate. The same order was observed for MK57. Neither of the strains lost plasmids during the entire course of each experiment. There was also little change in the pH of any of the media used for both strains. These results suggest that sodium octanoate, acylated ghrelin, and desacylated ghrelin, when compared with minimal medium, inhibitEscherichia coligrowth. Proliferation was lowest when sodium octanoate was used as the carbon source, followed by acylated ghrelin and desacylated ghrelin. Therefore, the acylated ghrelin found previously in human saliva might help to inhibit pathogenic microorganisms, and acylated ghrelin levels below a critical concentration in saliva could result in an increased risk of oral infection.

The Change of Ghrelin Levels in Intestinal Parasitic Infections

The Change of Ghrelin Levels in Intestinal Parasitic InfectionsThe aim of this work was to examine the relationship between active (acylated ghrelin) and inactive (desacylated ghrelin) ghrelin in the serum and other serum parameters in intestinal parasitic infections and healthy controls. Conventional microscopic methods (saline and iodine solutions, trichrome stain) were used to identify intestinal parasites in stool samples of 29 subjects attending Firat University Hospital. Serum parameters were assessed in a single measurement of serum from 29 parasite subjects, and in 18 healthy controls. Serum acylated ghrelin and desacylated ghrelin levels were measured using a commercial radioimmunoassay (RIA) kit. Paraoxonase and arylesterase were measured by using a spectrophotometer at 405 nm and 270 nm, respectively. Serum concentrations of acylated ghrelin and desacylated ghrelin were more markedly decreased in helminth bearing patients than the control group. Glucose, cholesterol and triglyceride levels were higher in intestinal parasitic infections than in controls. Furthermore, there were no correlations between ghrelin levels and BMI. These results indicate that low ghrelin and PON1/AE level may be important for appetite monitoring in intestinal parasitic infections.