This study was undertaken to identify the signaling events involved in activation of neutrophil superoxide anion (O2-) production by eosinophil granule major basic protein (MBP). MBP did not produce an immediate increase in the cytosolic free calcium concentration ([Ca2+]i), characteristic of phospholipase C activation, but did cause a gradual increase in [Ca2+]i in cytochalasin B-treated cells. Preincubation with 0.01 to 3 micrograms/mL pertussis toxin did not inhibit MBP-stimulated O2- production, and MBP did not stimulate an increase in diradylglycerol levels. MBP did stimulate a low level of phospholipase D activity, as measured by a time-dependent increase in phosphatidic acid and, in the presence of 0.5% ethanol, phosphatidylethanol. Inhibition of MBP-stimulated O2- production by genistein and Western blot analysis using an antiphosphotyrosine antibody showed tyrosine kinase activation by MBP. Calmodulin antagonists (calmidazolium and W-7) caused up to 80% inhibition of MBP-stimulated O2- production. In agreement with the pharmacologic sensitivity, MBP did not stimulate any 51Cr release. These data indicate that tyrosine kinase and calmodulin-dependent steps are involved in the noncytotoxic stimulation of neutrophil O2- production by MBP.

Download full-text PDF

Source

Publication Analysis

Top Keywords

o2- production
20
mbp-stimulated o2-
12
mbp stimulate
12
signaling events
8
activation neutrophil
8
neutrophil superoxide
8
superoxide anion
8
production eosinophil
8
eosinophil granule
8
granule major
8

Similar Publications

Non-metallic iodine single-atom catalysts with optimized electronic structures for efficient Fenton-like reactions.

Nat Commun

January 2025

State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, P.R. China.

In this study, we introduce a highly effective non-metallic iodine single-atom catalyst (SAC), referred to as I-NC, which is strategically confined within a nitrogen-doped carbon (NC) scaffold. This configuration features a distinctive C-I coordination that optimizes the electronic structure of the nitrogen-adjacent carbon sites. As a result, this arrangement enhances electron transfer from peroxymonosulfate (PMS) to the active sites, particularly the electron-deficient carbon.

View Article and Find Full Text PDF

Tuning Dual Catalytic Active Sites of Pt Single Atoms Paired with High-Entropy Alloy Nanoparticles for Advanced Li-O Batteries.

ACS Nano

January 2025

Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, School of Materials Science and Engineering, Shandong University, Jinan 250061, P. R. China.

To achieve a long cycle life and high-capacity performance for Li-O batteries, it is critical to rationally modulate the formation and decomposition pathway of the discharge product LiO. Herein, we designed a highly efficient catalyst containing dual catalytic active sites of Pt single atoms (Pt) paired with high-entropy alloy (HEA) nanoparticles for oxygen reduction reaction (ORR) in Li-O batteries. HEA is designed with a moderate d-band center to enhance the surface adsorbed LiO intermediate (LiO(ads)), while Pt active sites exhibit weak adsorption energy and promote the soluble LiO pathway (LiO(sol)).

View Article and Find Full Text PDF

Enhancing Catalytic Removal of Autoexhaust Soot Particles via the Modulation of Interfacial Oxygen Vacancies in Cu/CeO Catalysts.

Environ Sci Technol

January 2025

State Key Laboratory of Heavy Oil Processing, Key Laboratory of Optical Detection Technology for Oil and Gas, College of Science, China University of Petroleum, Beijing 102249, PR China.

The purification efficiency of autoexhaust carbon strongly depends on the heterogeneous interface structure between active metal and oxide, which can modulate the local electronic structure of defect sites to promote the activation of reactant molecules. Herein, the high-dispersion CuO clusters supported on the well-defined CeO nanorods were prepared using the complex deposition slow method. The formation of heteroatomic Cu-O-Ce interfacial structural units as active sites can capture electrons to achieve activation of the NO and O molecules.

View Article and Find Full Text PDF

Microencapsulation using a novel wall material prepared via Maillard reaction-derived mung bean protein-peach gum conjugates to enhance stability and functionality of chia seed oil.

Int J Biol Macromol

January 2025

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, PR China. Electronic address:

This study investigated the potential of Maillard reaction products (MRPs) derived from mung bean protein isolate (MBPI) and peach gum (PG) conjugates as wall materials for microencapsulating chia seed oil (CSO). Four formulations (MMRP) were prepared using spray-drying and compared to a commercial sample (CMMRP). The MMRP formulation exhibited the highest encapsulation yield (91 %) and encapsulation efficiency (96 %), along with favorable physical properties, including a spherical shape and smooth surface.

View Article and Find Full Text PDF

Ether bond-modified lipid nanoparticles for enhancing the treatment effect of hepatic fibrosis.

Int J Pharm

January 2025

National Advanced Medical Engineering Research Center, China State Institute of Pharmaceutical Industry, 285 Gebaini Road, Shanghai 201203, China. Electronic address:

Lipid nanoparticle (LNP)-mediated RNA delivery holds significant potential for the treatment of various liver diseases. Ionizable lipids play a crucial role in the formulation of LNPs and directly influence their delivery efficiency. In this study, we introduced an innovative concept by incorporating an ether bond into the hydrophobic tail of ionizable lipids for the first time.

View Article and Find Full Text PDF

Want 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!