Exploiting drug delivery systems for oral route in the peptic ulcer disease treatment

Microparticles and nanoparticles-based approaches to improve oral treatment of Helicobacter pylori infection

Helicobacter pylori is a gram-negative, spiral-shaped, flagellated bacterium that colonizes the stomach of half the world's population. Helicobacter pylori infection causes pathologies of varying severity. Standard oral therapy fails in 15-20% since the barriers of the oral route decrease the bioavailability of antibiotics and the intrinsic factors of bacteria increase the rates of resistance. Nanoparticles and microparticles are promising strategies for drug delivery into the gastric mucosa and targeting H. pylori. The variety of building blocks creates systems with distinct colloidal, surface, and biological properties. These features improve drug-pathogen interactions, eliminate drug depletion and overuse, and enable the association of multiple actives combating H. pylori on several fronts. Nanoparticles and microparticles are successfully used to overcome the barriers of the oral route, physicochemical inconveniences, and lack of selectivity of current therapy. They have proven efficient in employing promising anti-H. pylori compounds whose limitation is oral route instability, such as some antibiotics and natural products. However, the current challenge is the applicability of these strategies in clinical practice. For this reason, strategies employing a rational design are necessary, including in the development of nano- and microsystems for the oral route.

Amoxicillin-docosahexaenoic acid encapsulated chitosan-alginate nanoparticles as a delivery system with enhanced biocidal activities against Helicobacter pylori and improved ulcer healing

Encapsulation of amoxicillin (AMX) for drug delivery against Helicobacter pylori infection and aspirin-induced ulcers in rat's stomachs was performed using docosahexaenoic acid (DHA)-loaded chitosan/alginate (CA) nanoparticles (NPs) developed by ionotropic gelation method. The physicochemical analyses of the composite NPs were performed by scanning electron microscopy, Fourier transform infrared spectroscopy, zeta potential, X-ray diffraction, and atomic force microscopy. The encapsulation efficiency of AMX was increased to 76% by incorporating DHA, which resulted in a reduction in the particle size. The formed CA-DHA-AMX NPs effectively adhered to the bacteria and rat gastric mucosa. Their antibacterial properties were more potent than those of the single AMX and CA-DHA NPs as demonstrated by the in vivo assay. The composite NPs attained higher mucoadhesive potential during food intake than during fasting (p = 0.029). At 10 and 20 mg/kg AMX, the CA-AMX-DHA showed more potent activities against H. pylori than the CA-AMX, CA-DHA, and single AMX. The in vivo study showed that the effective dose of AMX was lower when DHA was included, indicating better drug delivery and stability of the encapsulated AMX. Both mucosal thickening and ulcer index were significantly higher in the groups receiving CA-DHA-AMX than in the groups receiving CA-AMX and single AMX. The presence of DHA declines the pro-inflammatory cytokines including IL-1β, IL-6, and IL-17A. The synergistic effects of AMX and the CA-DHA formulation increased the biocidal activities against H. pylori infection and improved ulcer healing properties.

Polymeric Coatings and Antimicrobial Peptides as Efficient Systems for Treating Implantable Medical Devices Associated-Infections

Many infections are associated with the use of implantable medical devices. The excessive utilization of antibiotic treatment has resulted in the development of antimicrobial resistance. Consequently, scientists have recently focused on conceiving new ways for treating infections with a longer duration of action and minimum environmental toxicity. One approach in infection control is based on the development of antimicrobial coatings based on polymers and antimicrobial peptides, also termed as “natural antibiotics”.