The role of the surrounding membrane structure on the binding characteristics of the insulin receptor was studied by using several digestive enzymes. The effects observed with particulate membrane preparations are compared with those from soluble receptor preparations. beta-Galactosidase and neuraminidase had no effect on insulin binding to either particulate or soluble receptors from human placentae. Exposure to 2 units of phospholipase C/ml increased insulin binding to particulate membranes, but was without effect on the soluble receptor preparation. The increase in binding to particulate membranes was shown to be due to an increase in apparent receptor number. After 5 min exposure to 500 microgram of trypsin/ml there was an increase in insulin binding to the particulate membrane fraction, owing to an increase in receptor affinity. After 15 min exposure to this amount of trypsin, binding decreased, owing to a progressive decrease in receptor availability. In contrast, this concentration of trypsin had no effect on the solubilized receptor preparation. Because of the differential effects of phospholipase C and trypsin on the particulate compared with the solubilized receptor preparations, it is concluded that the effects of these enzymes were due to an effect on the surrounding membrane structure. Changes in receptor configuration due to alterations within the adjoining membrane provide a potential mechanism for mediating short-term alterations in receptor function.
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http://dx.doi.org/10.1042/bj1740037 | DOI Listing |
J Hazard Mater
January 2025
SKL-ESPC and BIC-ESAT, College of Environmental Sciences and Engineering, Peking University, Beijing, China. Electronic address:
Minimal study focused on the association between mixed pollutants in atmospheric particulate matter (PM) and their reproductive health risks. Utilizing a novel quantitative structure-activity relationship (QSAR) integrated machine learning algorithms, we evaluated the mixed reproductive health risks associated with phthalates (PAEs) and organophosphates (OPEs) exposure by assessing the affinities of these compounds binding to estrogen receptors (ER) and androgen receptors (AR). The mixed toxicity equivalent factor (TEF) and mixed toxicity equivalent quantity (TEQ) by the QSAR model were all smaller than the sum TEF and TEQ of individual PAEs and OPEs, which may be due to the antagonistic effect of PAEs and OPEs monomers on reproductive toxicity.
View Article and Find Full Text PDFEnviron Epigenet
January 2025
Institute of Human Genetics, School of Medicine, Pontificia Universidad Javeriana, Bogotá 110231, Colombia.
Fine particulate matter (PM), an atmospheric pollutant that settles deep in the respiratory tract, is highly harmful to human health. Despite its well-known impact on lung function and its ability to exacerbate asthma, the molecular basis of this effect is not fully understood. This integrated transcriptomic and epigenomic data analysis from publicly available datasets aimed to determine the impact of PM exposure and its association with asthma in human airway epithelial cells.
View Article and Find Full Text PDFJ Air Waste Manag Assoc
January 2025
School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing, China.
Dust emissions from open-pit mining pose a significant threat to environmental safety and human health. Currently, the range of dust suppressants used in coal mining is limited, often failing to account for their suitability across various stockpiles. This oversight results in poor infiltration after application, leading to insufficient crust formation and reduced durability.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
School of Public Health, Capital Medical University, Beijing, 100069, P. R. China.
Substantial epidemiological evidence suggests a significant correlation between particulate matter 2.5 (PM) and lung cancer. However, the mechanism underlying this association needs to be further elucidated.
View Article and Find Full Text PDFGlob Chang Biol
January 2025
CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, China.
Coastal wetlands contain very large carbon (C) stocks-termed as blue C-and their management has emerged as a promising nature-based solution for climate adaptation and mitigation. The interactions among sources, pools, and molecular compositions of soil organic C (SOC) within blue C ecosystems (BCEs) remain elusive. Here, we explore these interactions along an 18,000 km long coastal line of salt marshes, mangroves, and seagrasses in China.
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