Antimycobacterial Effect of Selenium Nanoparticles on Mycobacterium tuberculosis.

Hector Estevez,Jose L Luque-Garcia,Maria Vallet-Regi,Juan Anguita,Ainhoa Palacios,David Gil,Blanca González,Rafael Prados-Rosales

doi:10.3389/fmicb.2020.00800

Abstract

Tuberculosis (TB) remains the leading cause of death from a single infection agent worldwide. In recent years, the occurrence of TB cases caused by drug-resistant strains has spread, and is expected to continue to grow. Therefore, the development of new alternative treatments to the use of antibiotics is highly important. In that sense, nanotechnology can play a very relevant role, due to the unique characteristics of nanoparticles. In fact, different types of nanoparticles have already been evaluated both as potential bactericides and as efficient drug delivery vehicles. In this work, the use of selenium nanoparticles (SeNPs) has been evaluated to inhibit the growth of two types of mycobacteria: Mycobacterium smegmatis (Msm) and Mycobacterium tuberculosis (Mtb). The results showed that SeNPs are able to inhibit the growth of both types of mycobacteria by damaging their cell envelope integrity. These results open a new opportunity for the use of this type of nanoparticles as antimycobacterial agents by themselves, or for the development of novel nanosystems that combine the action of these nanoparticles with other drugs.

Highlights

Tuberculosis (TB) is a chronic infectious disease transmitted aerially through droplets expelled by an infected person
A structural analysis of the mycobacteria subjected to the presence of the selenium nanoparticles (SeNPs) has been performed by means of electron microscopy to analyze their effect on the cell envelope, showing that SeNPs interact directly with the mycobacteria membrane of Mycobacterium tuberculosis (Mtb) and Mycobacterium smegmatis (Msm), compromising their integrity and inducing extrusion of cytoplasmic material
Selenium nanoparticles were prepared via a redox system in the presence of a biomacromolecule as soft template to control the nucleation and growth of the inorganic nanoselenium

Summary

INTRODUCTION

Tuberculosis (TB) is a chronic infectious disease transmitted aerially through droplets expelled by an infected person. TB treatment requires a 6-month regimen of four first-line drugs, which are ineffective at treating infection with multidrug-resistant (MDR) Mtb strains These strains are rapidly spreading worldwide (more than 480,000 cases reported last year according to the TB alliance) and could cost $16 trillion over the 35 years. Nanoparticles are highly promising as antimicrobials, complementary to antibiotics, as they act by influencing the bacterial cell wall by direct contact without the need to be endocytosed (Herman and Herman, 2014; Wang et al, 2017). Their small size implies a greater surface-area-to-volume ratio than bulk material. A structural analysis of the mycobacteria subjected to the presence of the SeNPs has been performed by means of electron microscopy to analyze their effect on the cell envelope, showing that SeNPs interact directly with the mycobacteria membrane of Mtb and Msm, compromising their integrity and inducing extrusion of cytoplasmic material

MATERIALS AND METHODS

RESULTS

DISCUSSION

DATA AVAILABILITY STATEMENT