Melatonin Nanoparticles Adsorbed to Polyethylene Glycol Microspheres as Activators of Human Colostrum Macrophages

Abstract

The effectiveness of hormones associated with polymeric matrices has amplified the possibility of obtaining new drugs to activate the immune system. Melatonin has been reported as an important immunomodulatory agent that can improve many cell activation processes. It is possible that the association of melatonin with polymers could influence its effects on cellular function. Thus, this study verified the adsorption of the hormone melatonin to polyethylene glycol (PEG) microspheres and analyzed its ability to modulate the functional activity of human colostrum phagocytes. Fluorescence microscopy and flow cytometry analyses revealed that melatonin was able to adsorb to the PEG microspheres. This system increased the release of superoxide and intracellular calcium. There was an increase of phagocytic and microbicidal activity by colostrum phagocytes when in the presence of melatonin adsorbed to PEG microspheres. The modified delivery of melatonin adsorbed to PEG microspheres may be an additional mechanism for its microbicidal activity and represents an important potential treatment for gastrointestinal infections of newborns.

The Effect of Melatonin Adsorbed to Polyethylene Glycol Microspheres on the Survival of MCF-7 Cells

“…The formation of the microspheres was thermally induced by subjecting the solution to 95°C for 5 min. For adsorption, the suspensions of PEG microspheres in PBS were incubated with melatonin (concentration 100 ng ml -1 ; Sigma) at 37°C for 30 min according to the method described by Hara et al [4]. …”

“…The adsorption capacity of the microspheres can be modified to improve the biological function of the organic compounds transported [3]. In an earlier study, we showed that PEG microspheres are a promising carrier for melatonin because they prevent the degradation of this hormone and increase its bioavailability, improving the immune response of the organism [4]. …”

Polyethyleneglycol nanoparticles adsorbed to glycine as a bioengineered neomaterial for application in inflammatory processes

“…It known that PEG nanoscale particle formulations can allow the control of the speed at which the drug is released from the polymer matrix [28]. In this sense the PEG nanoparticles have a high potential in the hormone transport system [19,20]. This material has biocompatible characteristics their degradation products do not present toxicity and are easily metabolized and excreted by natural physiological pathways [29].…”

“…PH = 6.8 using a modification of the described method [18,19,20]. For the synthesis of polyethylene glycol (PEG) nanoparticles (NP-PEG) with glycine adsorbed for the complex formation (NANO-PEG/GLY) PEG 6000 (10g) at the concentration of 0.016 mol/L, was diluted in 100 mL of phosphate buffered saline (PBS), incubated for 45 min at 45ºC.…”

“…Previous work showed that the adsorption of glycine onto Polyethylene glycol (PEG) microsphere was able to stimulate the colostrum macrophages and suggest that the controlled delivery system of glycine may be an additional mechanism of protection and treatment of patients with infections and/or inflammation gastrointestinais, as well as for the functioning of colostrum cells [7]. Considering that the PEG is a biodegradable and biocompatible component [14] and that this particles have the capacity not to be recognized by the immune system, circulate for longer periods in the body [15,16,17] ] and has the ability to adsorb organic compounds, it is possible that this carrier of biological components to be used in the treatment of gastrointestinal inflammation [7,18,19,20]. The aim of this study was to evaluate the efficiency of the synthesis of polyethylene glycol (PEG) nanoparticles adsorbed with glycine (NANO-PEG/GLY) on functional activity of colostrum macrophages.…”