Co-delivery of Diverse Therapeutic Compounds Using PEG-PLGA Nanoparticle Cargo against Drug-Resistant Bacteria: An Improved Anti-biofilm Strategy.

Controlling biofilms of bacteria is a challenging aspect because of their drug-resistance potentials against a range of antibiotics, demanding the development of active anti-biofilm agents. Rutin (R), a natural antioxidant, and benzamide (B), a synthetic antibacterial agent, have several pharmacological and antibacterial abilities. Herein, we developed PEG-PLGA NPs that synergistically carried rutin and benzamide as drug candidates, while displaying therapeutic and anti-biofilm  functions. These drug delivery NPs were synthesized by the oil-in-water emulsion (O/W) solvent evaporation technique. The obtained NPs were characterized by UV-vis, FT-IR, SEM, TEM, and DLS measurements. Confocal laser scanning microscopy was employed to evaluate the anti-biofilm capabilities against Staphylococcus aureus and Pseudomonas aeruginosa and further quantified the levels of residual biofilm constituents such as protein and exopolysaccharide (EPS). Drug release experiments showed the controlled release of rutin-benzamide (RB) for several days. Antibacterial analyses showed that the minimum inhibitory concentration (MIC) of NPs was at least two times lower than that of the free drugs. RB-PEG-PLGA NPs revealed that they targeted biofilm-forming bacteria through the disruption of the membrane and biofilm surface and were observed to be nontoxic when tested using human erythrocytes and human cell lines. In vivo evaluations in zebrafish showed that the NPs did not alter the antioxidant functions and histological features of tissues. On the basis of results obtained, it is substantiated that the rutin-benzamide-loaded nanocarrier offers potential anti-biofilm therapy due to its high anti-biofilm activity and biocompatibility.

Dual drug loaded PLGA nanospheres for synergistic efficacy in breast cancer therapy.

Improved therapeutic effects can be achieved by the delivery of combination of drugs through multifunctional cell targeted nanocarrier systems. The present investigation reports the preparation of Poly (D,L-lactic-co-glycolic acid) (PLGA) nanospheres loaded with the novel combination such as Rutin (R) and Benzamide (B) as drugs using water-oil-water (w/o/w) emulsion method. Dual drug loaded PLGA nanospheres (R/B@PLGA) were stabilized by poly (vinyl alcohol) (PVA) coating and characterized in terms of morphology, size, surface charge, and structural chemistry by Scanning electron microscopy (SEM), Dynamic light scattering (DLS), Zeta potential analysis, UV-vis and Fourier transform infrared (FT-IR) spectroscopy. The inhibitory effects of rutin and benzamide on MDA-MB-231 (triple negative breast cancer-TNBC) cells using the drug loaded PLGA nanospheres as well as their non-toxic features were evaluated in vivo. The anticancer activity of the R/B@PLGA nanospheres through cell cycle disruption and apoptotic induction was assessed in vitro by flow cytometry analysis. Further, the in vitro antioxidant capacity, pH-based drug release and hemocompatible property were also investigated. It was shown that the R/B@PLGA nanospheres lacked genotoxic potential and they did not alter the antioxidant enzyme activities and histological features of zebrafish. Hence, this dual drug delivery system (DDS) not only actively targets multidrug-resistance (MDR) associated phenotype but also improves the therapeutic efficiency by its non-toxic nature towards enhanced cancer cell focused delivery and sustained release of therapeutic agents.

Antibacterial synergy between rutin and florfenicol enhances therapeutic spectrum against drug resistant Aeromonas hydrophila.

Emergence of antibiotic resistant bacteria has necessitated the drive to explore competent antimicrobial agents or to develop novel formulations to treat infections including Aeromonas hydrophila. The present study investigates the synergistic antibacterial effects of citrus flavonoid rutin and florfenicol (FF) against A. hydrophila in vitro and in vivo. Rutin is extracted and purified from Citrus sinensis peel through preparative HPLC and characterized through TLC, GC-MS and 1H and 13C NMR analyses. Though rutin did not display significant antibacterial activity, it modulated FF activity resulting in four-fold reduction in the MIC value for FF. The anti-biofilm potential of synergistic association of rutin and FF was validated by protein analysis, quantification of exopolysaccharide (EPS) and microscopy studies using sub-MIC doses. Besides antibacterial action, in vivo studies showed that Rutin/FF combination enhanced host immunity by improving blood cell count, anti-protease, and lysozyme activities as well as decreased the oxidative stress and the pathological changes of tilapia Oreochromis niloticus against A. hydrophila infection. No significant DNA damages or clastogenic effects were detected in tilapia challenged with A. hydrophila under Rutin/FF treatment. It is shown that an acute-phase Lipopolysaccharide binding protein (LBP) enhances the innate host defence against bacterial challenge. Semi quantitative RT-PCR and western blot results revealed the significant increase of LBP in the supernatant of tilapia monocytes/macrophages challenged with A. hydrophila upon treatment. The study findings substantiate that the combination of natural molecules with antibiotics may open up possibilities to treat MDR strains.

A novel rutin-fucoidan complex based phytotherapy for cervical cancer through achieving enhanced bioavailability and cancer cell apoptosis.

Recent studies on flavonoids forming complexes with macromolecules attract researchers due to their enhanced bioavailability as well as chemo-preventive efficacy. In this study, a flavonoid rutin (Ru) is non-covalently complexed with fucoidan (Fu) using the functional groups to obtain a therapeutic polymeric complex overcoming the limitations of bioavailability of rutin. The prepared novel rutin-fucoidan (Ru-Fu) complex is characterized for spectroscopic features, particle size and distribution analysis by DLS. It is shown that the complex displayed the nanostructural features that are different from that of the usual rutin-fucoidan mixture. The studies on drug release profiles at different pH (5.5, 6.8 and 7.4) show that the sustained release of compounds from complex occurs preferentially at the desired endosomal pH (5.5). Further, the chemopreventive potential of Ru-Fu complex is investigated against HeLa cells by cellular apoptotic assays and flow cytometric analysis. It showed that the complex is able to disrupt cell cycle regulation and has the ability to induce cellular apoptosis via nuclear fragmentation, ROS generation and mitochondrial potential loss. In vitro cell viability assay with Ru-Fu complex shows that the complex is biocompatible on normal cells. The hemolysis assay also reveals that the complex does not release hemoglobin from human red blood cells (RBCs). Thus, the study is envisaged to open up interests for developing such formulations against cervical cancer and other cancers.