Hypothesis: It has been recently shown that, in our organism, the secretions of Ca2+, Mg2+ and phosphate ions lead to the precipitation of amorphous magnesium-calcium phosphate nanoparticles (AMCPs) in the small intestine, where the glycoprotein mucin is one of the most abundant proteins, being the main com- ponent of the mucus hydrogel layer covering gut epithelium. Since AMCPs precipitate in vivo in a mucin- rich environment, we aim at studying the effect of this glycoprotein on the formation and features of endogenous-like AMCPs. Experiments: AMCPs were synthesized from aqueous solution in the presence of different concentrations of mucin, and the obtained particles were characterised in terms of crystallinity, composition and mor- phology. Solid State NMR investigation was also performed in order to assess the interplay between mucin and AMCPs at a sub-nanometric level. Finding: Results show that AMCPs form in the presence of mucin and the glycoprotein is efficiently incor- porated in the amorphous particles. NMR indicates the existence of interactions between AMCPs and mucin, revealing how AMCPs in mucin-hybrid nanoparticles affect the features of both proteic and oligosaccharidic portions of the glycoprotein. Considering that the primary function of mucin is the pro- tection of the intestine from pathogens, we speculate that the nature of the interaction between AMCPs and mucin described in the present work might be relevant to the immune system, suggesting a novel type of scenario which could be investigated by combining physico-chemical and biomedical approaches.
Exploring the interplay of mucin with biologically-relevant amorphous magnesium-calcium phosphate nanoparticles
Martini FrancescaSecondo
;Geppi Marco;
2021-01-01
Abstract
Hypothesis: It has been recently shown that, in our organism, the secretions of Ca2+, Mg2+ and phosphate ions lead to the precipitation of amorphous magnesium-calcium phosphate nanoparticles (AMCPs) in the small intestine, where the glycoprotein mucin is one of the most abundant proteins, being the main com- ponent of the mucus hydrogel layer covering gut epithelium. Since AMCPs precipitate in vivo in a mucin- rich environment, we aim at studying the effect of this glycoprotein on the formation and features of endogenous-like AMCPs. Experiments: AMCPs were synthesized from aqueous solution in the presence of different concentrations of mucin, and the obtained particles were characterised in terms of crystallinity, composition and mor- phology. Solid State NMR investigation was also performed in order to assess the interplay between mucin and AMCPs at a sub-nanometric level. Finding: Results show that AMCPs form in the presence of mucin and the glycoprotein is efficiently incor- porated in the amorphous particles. NMR indicates the existence of interactions between AMCPs and mucin, revealing how AMCPs in mucin-hybrid nanoparticles affect the features of both proteic and oligosaccharidic portions of the glycoprotein. Considering that the primary function of mucin is the pro- tection of the intestine from pathogens, we speculate that the nature of the interaction between AMCPs and mucin described in the present work might be relevant to the immune system, suggesting a novel type of scenario which could be investigated by combining physico-chemical and biomedical approaches.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
