Ádám Simon

Capillary electrophoresis analysis of N-glycosylation changes of serum paraproteins in multiple myeloma

Multiple myeloma (MM) is an immedicable malignancy of the human plasma cells producing abnormal antibodies (also referred to as paraproteins) leading to kidney problems and hyperviscosity syndrome. In this paper, we report on the N‐glycosylation analysis of paraproteins from total human serum as well as the fragment crystallizable region (Fc) and fragment antigen binding (Fab) κ/λ light chain fractions of papain digested immunoglobulins from multiple myeloma patients. CE‐LIF detection was used for the analysis of the N‐glycans after endoglycosidase (PNGase F) mediated sugar release and fluorophore labeling (APTS). While characteristic N‐glycosylation pattern differences were found between normal control and untreated, treated and remission stage multiple myeloma patient samples at the global serum level, less distinctive changes were observed at the immunoglobulin level. Principal component analysis adequately differentiated the four groups (control and three patient groups) on the basis of total serum N‐glycosylation analysis. 12 N‐glycan features showed statistically significant differences (p <0.05) among various stages of the disease in comparison to the control at the serum level, while only six features were identified with similar significance at the immunoglobulin level, including the analysis of the partitioned Fc fragment as well as the Fabκ and Fabλ chains.

Changes in expression of neuropeptides and their receptors in the hypothalamus and gastrointestinal tract of calorie restricted hens

The list of orexigenic and anorexigenic peptides, those are known to alter feed intake, is continuously growing. However, most of them are studied in mammalian species. We aimed to investigate plasma level and mRNA expression of the pituitary adenylate cyclase-activating polypeptide (PACAP), gene expression of its receptor (PAC1), furthermore the gene expression of galanin (GAL), neuromedin U (NMU), and its two receptors (NMUR1 and NMUR2) in the hypothalamus, proventriculus, and jejunum of hens exposed to 40% calorie restriction. Feed restriction resulted in a 88% increase in mRNA and a 27% increase in peptide level of PACAP in proventriculus measured with qPCR and RIA, respectively. Increases were found in the gene expression of PAC1 (49%) and NMUR1 (63%) in the hypothalamus. Higher expressions of peptide encoding genes (76% for PACAP, 41% for NMU, 301% for NMUR1 and 308% for GAL, P < 0.05) were recorded in the jejunum of hens exposed to restricted nutrition. The results indicate that PACAP level responds to calorie restriction in the proventriculus and jejunum, but not in the hypothalamus and plasma.

Feeding state and age dependent changes in melanin-concentrating hormone expression in the hypothalamus of broiler chickens

We aimed to quantify the gene expression changes of the potent orexigenic melanin-concentrating hormone (MCH) in chicken (Gallus gallus) hypothalamus with quantitative real-time polymerase chain reaction (qPCR), and for the first time determine peptide concentrations with a novel radioimmunoassay (RIA) under different feeding status. Three different experimental conditions, namely ad libitum feeding; fasting for 24 h; fasting for 24 h and then refeeding for 2 h, were applied to study changes of the aforementioned target and its receptor (MCHR4) gene expression under different nutritional status. The relative changes of MCH and MCHR4 were also studied from 7 to 35 days of age. Expression of PMCH and MCHR4 along the gastrointestinal tract (GIT) was also investigated. We found that expression of both targets was significant in the hypothalamus, while only weak expression was detected along the GIT. Different nutritional states did not affect the PMCH and MCHR4 mRNA levels. However, fasting for 24 h had significantly increased the MCH-like immunoreactivity by 25.65%. Fasting for 24 h and then refeeding for 2 h had further significantly increased the MCH peptide concentration by 32.51%, as compared to the ad libitum state. A decreasing trend with age was observable for both, the PMCH and MCHR4 mRNA levels, and also for the MCH-like immunoreactivity. Correlation analysis did not result in a significant correlation between MCH peptide concentration and abdominal fat mass in ad libitum fed birds. In conclusion, MCH peptide concentration altered in response to 24 h fasting, which indicated that this peptide may take part in feed intake regulation of broiler chickens.