The analogues of oxytocin and [1-penicillamine]oxytocin, containing a cycloleucine (Cle) residue in position 2 or 8, were investigated by means of circular dichroism measurements in different solvents, and the results examined in terms of their biological activities. A cycloleucine residue in position 2 substantially reduces the free conformational space of the hormone 20-membered ring moiety (including the disulfide group), and stabilizes a conformation which is close to one of the possible conformations of oxytocin and involves a beta-turn. In position 8, the Cle residue affects the conformation of the Tyr2 side chain, apparently forcing it away from the space above the 20-membered disulfide ring. However, it does not appear that the Cle residue has any significant effect on the overall backbone conformation of the hormone. The steric effect of the penicillamine residue in position 1 on the conformation of the disulfide group and Tyr2 side chain from previous investigations is further confirmed. The synthesis and biological potency of [1-penicillamine, 8-cycloleucine]oxytocin is described. This analogue exhibits a strong inhibitory effect on the uterotonic activity of oxytocin in vitro. It also inhibited the vasopressor response to vasopressin.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/BF01024978 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Role of CLE peptide signaling in root-knot nematode parasitism of plants.
Planta
November 2024
Section of Plant Pathology and Nematology, Aligarh Muslim University, Aligarh, 202002, India.
Article Synopsis
- - Recent research has focused on the role of CLE (CLAVATA3/EMBRYO SURROUNDING REGION-RELATED) peptides, which are short sequences of amino acids, in regulating plant development and their interaction with parasitic nematodes.
- - These CLE peptides interact with specific receptors on plant cell membranes, triggering complex signaling pathways that influence various developmental processes and responses to infection.
- - The findings highlight the importance of CLE peptides in both normal plant growth and defense mechanisms against plant-parasitic nematodes, showing their diverse roles across different plant species.
Data collection initiatives of the crop protection industry - A mission to improve non-dietary risk assessment in Europe.
Regul Toxicol Pharmacol
December 2024
BASF Oesterreich GmbH, Vienna, Austria.
Plant protection products (PPPs) undergo rigorous safety assessments. In Europe, non-dietary risk assessments for operators, workers, bystanders and residents are highly conservative as this area of exposure science has historically been data poor. CropLife Europe (CLE) companies have collaborated to generate new data and pool existing data to refine the approaches prescribed by the European Food Safety Authority (EFSA) guidance on non-dietary exposure (2022).
View Article and Find Full Text PDFCore-satellite-structured magnetic nanozyme enables the ultrasensitive colorimetric detection of multiple drug residues on lateral flow immunoassay.
Anal Chim Acta
October 2024
Department of Clinical Laboratory Medicine, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, Guangdong, 510000, China. Electronic address:
Background: Excessive use of veterinary drugs causes severely environmental pollution and agricultural pollution, and poses great threat to human health. A simple method for the rapid, highly sensitive, and on-site monitoring of veterinary drug residues in complex samples remains lacking.
Results: In this study, we propose a catalytically enhanced colorimetric lateral flow immunoassay (LFA) based on a novel core-satellite-structured magnetic nanozyme (Fe-Au@Pt) that can simultaneously and quantitatively detect three common veterinary drugs, namely, gentamicin (GM), streptomycin (STR), and clenbuterol (CLE), within a short testing time (<30 min).
The importance of stratum corneum ω-linoleoyloxyacylceramides in human skin barrier health: their biochemistry, processing enzymes and metabolites involved in corneocyte lipid envelope maturation.
Int J Cosmet Sci
August 2024
DSM-Firmenich, Kaiseraugst, Switzerland.
Over the past 50 years there have been great strides made in the discovery of the composition and relevance of the total stratum corneum (SC) ceramide matrix. However, the focus of this review is on the free intercellular class of ω-linoleoyloxyacylceramides, corneocyte-bound ceramides and associated lipids known as the corneocyte lipid envelope (CLE) together with their processing enzymes involved in aiding ceramide attachment the corneocyte protein envelope (CPE). Two structural models and partially shared biosynthetic pathways have been proposed for the attachment of CPE-bound O-ceramides (ω-hydroxyceramides attached to glutamate residues of proteins in the (CPE) using the 12R-lipoxygenase (12R-LOX)/epidermal lipoxygenase-3 (eLOX3)/epoxide hydrolase-3 (EPHX3)/unknown esterase/ transglutaminase-1 (TG1) attachment pathway) and CPE-bound EO-ceramides (epoxy-enone ceramides attached to cysteine residues of proteins in the CPE using the 12R-LOX/eLOX3/short chain dehydrogenase/reductase family 9C member 7 (SDR9C7)/non-enzymatic attachment pathway), i.
View Article and Find Full Text PDFCoffee leaf extract inhibits advanced glycation end products and their precursors: A mechanistic study.
J Food Sci
June 2024
School of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu, P.R. China.
Excessive accumulation of advanced glycation end products (AGEs) in the body is associated with diabetes and its complications. In this study, we aimed to explore the potential and mechanism of coffee leaf extract (CLE) in inhibiting the generation of AGEs and their precursors in an in vitro glycation model using bovine serum albumin and glucose (BSA-Glu) for the first time. High-performance liquid chromatography analysis revealed that CLE prepared with ultrasound pretreatment (CLE-U) contained higher levels of trigonelline, mangiferin, 3,5-dicaffeoylquinic acid, and γ-aminobutyric acid than CLE without ultrasound pretreatment (CLE-NU).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!