The regulatory properties of the divalent metal ions Mg2+, Ca2+ and Mn2+ on the activity and kinetic behaviour of rat liver microsomal cholesterol esterase were studied in vitro. Mg2+ and Ca2+ exhibited similar concentration and preincubation time-dependent increases in esterase activity, with maximal stimulation at a concentration of 2 mM. However, Mn2+ had no effect at this concentration but displayed a potent inhibitory effect at concentrations above 20 mM. Activation of cholesterol esterase by Mg2+ and Ca2+ was selective in relation to i) the changes that cations produced in the enzyme kinetic constants, and ii) the chelating agents that reversed the metal ion-induced activation. Hence, the maximum rate of cholesterol ester hydrolysis doubled in the presence of Mg2+ and activation was reversed by EDTA, whereas a significant decrease in the apparent Km for cholesterol oleate was found when Ca2+ was added and this effect was blocked by ATP and EGTA. Both cations were able to reactivate cholesterol ester hydrolase activity in metal-depleted microsomes.
Download full-text PDF |
Source |
---|
Int J Biol Macromol
January 2025
College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, PR China. Electronic address:
In this study, water-soluble fraction (WSF), chelator-soluble fraction (CSF), and sodium carbonate-soluble fraction (NSF) were sequentially fractionated from pear pulp, of which physicochemical properties and hypolipidemic activities in vitro were evaluated. They showed distinct monosaccharide composition, surface morphology, nuclear magnetic resonance (NMR), and Fourier transform infrared (FT-IR) spectrums. WSF and NSF were identified as high methyl-esterified pectic polysaccharides with degrees of methyl esterification (DM) of 85.
View Article and Find Full Text PDFNutrients
December 2024
Pediatric Hepatology and Liver Transplant Unit, Department of Pediatrics, ERN Rare Liver ERN TransplantChild, Vall d'Hebron Barcelona Hospital Campus, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain.
Lysosomal acid lipase deficiency (LAL-D) is an ultra-rare lysosomal storage disease with two distinct phenotypes, an infantile-onset form (formerly Wolman disease) and a later-onset form (formerly cholesteryl ester storage disease). The objective of this narrative review is to examine the most important aspects of the diagnosis and treatment of LAL-D and to provide practical expert recommendations. The infantile-onset form occurs in the first weeks of life and is characterized by malnourishment and failure to thrive due to gastrointestinal impairment (vomiting, diarrhea, malabsorption), as well as systemic inflammation, hepatosplenomegaly, and adrenal calcifications.
View Article and Find Full Text PDFSci Adv
January 2025
Institute for Diabetes, Obesity and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
J Dent Res
December 2024
Dentistry, School of Health Sciences, College of Medicine and Health, University of Birmingham, Birmingham, UK.
Root canal obturation involves filling of the chemomechanically prepared root canal space. Despite reduced microbial load, residual bacteria can still lead to reinfection and treatment failure. Currently, obturation techniques use a combination of gutta-percha and sealer, which requires the preparation of the root canal to specific sizes and tapers to enable the fitting of customized cones.
View Article and Find Full Text PDFFood Chem X
December 2024
Department of Food Science, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al-Ain 15551, United Arab Emirates.
Fermented milk (FM) is well-known to confer health-promoting benefits, particularly for managing chronic metabolic diseases. However, the specific cholesterol esterase (CE) inhibitory activities of FM produced from different animal milk sources have not been extensively explored. This study for the first time investigates the CE inhibition potential of FM derived from bovine (F_BM), camel (F_CM), sheep (F_SM), and goat milk (F_GM), each fermented with five different probiotic strains and stored for 14 days under refrigeration.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!