The effects of Bisphenol A on the Zebrafish embryo

Abstract only availableEndocrine disruptors are compounds that mimic hormones found in the endocrine system and, in doing so, alter the physiology of living organisms by affecting this regulatory system. Bisphenol A, a monomer used in polycarbonate plastics that is at the center of international controversy, is thought to act as an endocrine disruptor. Its application in shatterproof dishware is especially hazardous, due to the widespread use of polycarbonate plastics in the production of cups for infants and toddlers. This age group is especially prone to the acute effects of endocrine disruptors due to a weaker feedback regulatory system than in adults. Thus, my project focuses on the action of Bisphenol A in the developing organism, specifically, the zebrafish (Danio rerio) embryo. My previous work has shown that BPA treatment caused a 50-75% reduction in heart rate, a transient effect that is fully reversed upon its removal from the culture medium. Other symptoms of BPA treatment included cardiac edemas, muscular malformation, depigmentation, slow response time, and retardation of swim bladder inflation; all reported symptoms of other endocrine disruptors. Other previous experiments have also shown that this effect (in zebrafish) is not due to estrogen agonism and may be caused by a yet uninvestigated mechanism. To determine the chemical specificity required for heart rate reduction, I investigated several structural analogs of BPA. These experiments showed that while IDP and BPAF cause a similar (or more gravid) effect, BPS shows no activity in reducing heart rate. Since underlying cellular irregularities could cause the heart rate reduction seen with BPA treatment, I also used Immunohistochemical techniques on transgenic fish to study any defects in the developing vascular endothelium. My results illustrate that vascular endothelial development is not affected due to BPA treatment and does not cause the heart rate reduction seen in BPA treated fish

Purification and analysis of human muc reporter proteins

Abstract only availableExocrine mucous glycoproteins are a family of multifunctional heavily glycosylated, anionic macromolecules that typically possess a high serine/threonine content. The size and complexity of these glycoprotein molecules, while physiologically beneficial, prohibits direct analysis of small-to-moderate changes within the side-chain oligosaccharides. These polydispersed molecules have a protein core encoded by muc-genes, which possess multiple repeats within their sequences. To assist in developing a method to study these complex molecules, a reporter-DNA construct, for eventual eukaryotic expression, consisting of an IgK secretory leader sequence, two polyHis regions, two HSV and one myc antigenic sites was synthesized. This construct was then utilized by incorporating two separate muc repeat-sequence units; one consisting of muc-2/muc-2 and one possessing muc-2/muc-4 (i.e., amuc2c and amuc24c, respectively). DNA plasmids pET28-amuc2c and pET28-amuc24c were transformed into the bacterial strain Ecoli BL21DE3. Expressed proteins from transformants were isolated and purified, and then analyzed by MALDI-TOF MS. Mass+H+ (avg) of 16306.2 Da and 17062.8 Da for amuc2c and amuc24c, respectively, were observed. MS and MS/MS analysis of the tryptic digests of these expressed proteins also confirmed their respective sequences. To test the efficacy of possible coexpression of fluorescent protein transfection markers with the muc-constructs in eukaryotic cells, preliminary transfections of fluorescent DNA plasmids pEGFPc1 (green, cytoplasmic), pDSRed2-N1 (red, secretory-IgK), pEYFP-Golgi (yellow) and pECFP-Golgi (cyan) into MATLyLu cells (rat prostate cancer) are being performed. The successful conclusion of these ongoing studies will result in the expression of a small, glycated, and secreted muc-protein from transfected human intestional and respiratory cells in vitro that also are producing muc-related macromolecules. These posttranslationally modified amuc2c and amuc24c reporter proteins can then be analyzed, in detail, by contemporary methods. They will be employed as tools to help provide an insight into the changes that occur in the posttranslational modifications of macromolecular glycoproteins in human disease, such as cystic fibrosis

Automated synthesis of PET radiotracers by copperâ mediated 18Fâ fluorination of organoborons: Importance of the order of addition and competing protodeborylation

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142980/1/jlcr3583_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/142980/2/jlcr3583.pd

Cinnamic Acid and Its Derivatives Inhibit Fructose-Mediated Protein Glycation

Cinnamic acid and its derivatives have shown a variety of pharmacologic properties. However, little is known about the antiglycation properties of cinnamic acid and its derivatives. The present study sought to characterize the protein glycation inhibitory activity of cinnamic acid and its derivatives in a bovine serum albumin (BSA)/fructose system. The results demonstrated that cinnamic acid and its derivatives significantly inhibited the formation of advanced glycation end products (AGEs) by approximately 11.96–63.36% at a concentration of 1 mM. The strongest inhibitory activity against the formation of AGEs was shown by cinnamic acid. Furthermore, cinnamic acid and its derivatives reduced the level of fructosamine, the formation of Nɛ-(carboxymethyl) lysine (CML), and the level of amyloid cross β-structure. Cinnamic acid and its derivatives also prevented oxidative protein damages, including effects on protein carbonyl formation and thiol oxidation of BSA. Our findings may lead to the possibility of using cinnamic acid and its derivatives for preventing AGE-mediated diabetic complications