Alpha-Gal on the Protein Surface Hampers Transcytosis through the Caco-2 Monolayer

Transepithelial transport of proteins is an important step in the immune response to food allergens. Mammalian meat allergy is characterized by an IgE response against the carbohydrate moiety galactosyl-α-1,3-galactose (α-Gal) present on mammalian glycoproteins and glycolipids, which causes severe allergic reactions several hours after red meat consumption. The delayed reaction may be related to the processing of α-Gal carrying proteins in the gastrointestinal tract. The aim of this study was to investigate how protein glycosylation by α-Gal affects the susceptibility to gastric digestion and transport through the Caco-2 cell monolayer. We found that α-Gal glycosylation altered protein susceptibility to gastric digestion, where large protein fragments bearing the α-Gal epitope remained for up to 2 h of digestion. Furthermore, α-Gal glycosylation of the protein hampered transcytosis of the protein through the Caco-2 monolayer. α-Gal epitope on the intact protein could be detected in the endosomal fraction obtained by differential centrifugation of Caco-2 cell lysates. Furthermore, the level of galectin-3 in Caco-2 cells was not affected by the presence of α-Gal glycosylated BSA (bovine serum albumin) (BSA-α-Gal). Taken together, our data add new knowledge and shed light on the digestion and transport of α-Gal glycosylated proteins

Prolactin Receptor in Primary Hyperparathyroidism – Expression, Functionality and Clinical Correlations

<div><h3>Background</h3><p>Primary hyperparathyroidism (PHPT) is an endocrine disorder most commonly affecting women, suggesting a role for female hormones and/or their receptors in parathyroid adenomas. We here investigated the prolactin receptor (PRLr) which is associated with tumours of the breast and other organs.</p> <h3>Methodology/Principal Findings</h3><p>PRLr expression was investigated in a panel of 37 patients with sporadic parathyroid tumours and its functionality in cultured parathyroid tumour cells. In comparison with other tissues and breast cancer cells, high levels of prolactin receptor gene (<em>PRLR</em>) transcripts were demonstrated in parathyroid tissues. PRLr products of 60/70 kDa were highly expressed in all parathyroid tumours. In addition varying levels of the 80 kDa PRLr isoform, with known proliferative activity, were demonstrated. In parathyroid tumours, PRLr immunoreactivity was observed in the cytoplasm (in all cases, n = 36), cytoplasmic granulae (n = 16), the plasma membrane (n = 12) or enlarged lysosomes (n = 4). In normal parathyroid rim (n = 28), PRLr was uniformly expressed in the cytoplasm and granulae. In <em>in vitro</em> studies of short-term cultured human parathyroid tumour cells, prolactin stimulation was associated with significant transcriptional changes in JAK/STAT, RIG-I like receptor and type II interferon signalling pathways as documented by gene expression profiling. Moreover, <em>PRLR</em> gene expression in parathyroid tumours was inversely correlated with the patients’ plasma calcium levels.</p> <h3>Conclusions</h3><p>We demonstrate that the prolactin receptor is highly abundant in human parathyroid tissues and that PRLr isoforms expression and PRLr subcellular localisation are altered in parathyroid tumours. Responsiveness of PRLr to physiological levels of prolactin was observed in the form of increased PTH secretion and altered gene transcription with significant increase of RIG-I like receptor, JAK-STAT and Type II interferon signalling pathways. These data suggest a role of the prolactin receptor in parathyroid adenomas.</p> </div

Spectrophotometric investigation of uranil(II)-rutin complex in 70% ethanol

The composition and stability constant of a UO2(II)-rutin complex in 70% ethanol were determined by suitable spectrophotometric methods and pH measurement. UO2(II) ion and rutin (3,3',4',5,7-pentahydroxyflavone-3-rhamnoglucoside) form a 1:1 complex in which the UO2(II) ion is linked to rutin through the carbonyl and 5-hydroxyl group. The concentration stability constant of the complex, log beta(1), ranged from 6.57 at pH 4.00 to 4.72 at pH 7.00. Conditions for spectrophotometric determination of rutin, by complex formation with UO2(II) ion, were investigated. Beer's law was obeyed in the concentration range from 1.0 x 10(-5) to 2.0 x 10(-4) M for rutin. Determination of rutin in Rutinion forte tablets was demonstrated

Synthesis, characterization, and biological activity of amino acid derivatives of the heteropolytungstophosphoric acid

Compounds of phosphotungstic acid (WPA) containing the amino acids alanine (WPA-Ala) or glycine (WPA-Gly) as counter cations were synthesized and characterized by elemental analysis, thermal analysis, and IR spectroscopy. Cellular toxicity was assessed by the trypan blue exclusion method, and the antiviral activity of WPA and the modified WPA compounds was tested against herpes simplex viruses (HSV) type 1 and type 2. Biological assays indicate that the newly synthesized compounds exhibit no evident cytotoxic effects on Vero cells and negligible antiviral activity against HSV-1 and HSV-2