Инфекционные заболевания: профилактика и контроль

Infection Control 2018: Silver nanoparticles as a therapeutic agent in experimental cyclosporiasis

Mona El-Temsahy

Cyclosporiasis is an emerging worldwide infection caused by an obligate intracellular protozoan parasite, Cyclospora caytenensis. The standard treatment for cyclosporiasis is a combination of two antibiotics, trimethoprim and sulfamethoxazole. Many side effects were reported with this combination with no alternative drug treatment option. In this study, silver nanoparticles were chemically synthesized to be evaluated for the first time for their anti-cyclospora effects in both immunocompetent and immunosuppressed experimental mice in comparison to the standard treatment. The effect of silver nanoparticles was assessed through studying stool oocysts’ load, oocysts’ viability, ultrastructural oocysts’ changes, and estimation of serum gamma interferon. Toxic effect of the drug was evaluated by measuring liver enzymes, urea and creatinine in mice sera. Results showed that silver nanoparticles had promising anti-cyclospora potentials. The animals that received these nanoparticles showed statistically significant decrease in the oocysts’ burden and number of viable oocysts in the mice stool and a statistically significant increase in serum gamma interferon in comparison to the corresponding group receiving the standard treatment and to the infected non-treated control group. Scanning Electron microscopic examination revealed mutilated oocysts with irregularities, poring and perforations. These effects were more pronounced in immunosuppressed animals. Biochemical results showed no evidence of toxicity as mice sera showed a statistically significant decrease in liver enzymes, and statistically non-significant decrease in urea and creatinine. Thus, silver nanoparticles proved their effectiveness against Cyclospora infection and this will open the way to its use as an alternative to the standard therapy.

 

Industrially arranged nanoparticles were acquired with known size and different particulars. Silver nanoparticles utilized were bought from Sigma Aldrich, (item no; 576832) which had a molecule size of under 100nm.

Readiness of nanoparticle arrangement: Silver nanoparticles were acquired scattering structure with known focuses from which various fixations were made by dissolving them in refined water. Nanofluids arranged were autoclaved at 121ºC for 20 min and afterward chilled off to room temperature.

Well dispersion strategy: The agar well dissemination was finished utilizing the technique by Valodkar M et al., with certain changes in this investigation. The saboraud dextrose agar for growths seeded with the test life forms was punched with a sterile stopper borer (0.5cm distance across) to make open wells. AgNPs were included away from any detectable hindrance wells at various focuses (0.062, 0.125, 0,250, 0.5, 1µg/ml). The plates were brooded at 37°C at 25°C for max. 6 days for C. albicans. A similar test is performed with ATCC 24433 Candida albicans as the control with similar medication fixations. The zones of restraint were estimated in mm and recorded. The most minimal centralization of AgNPs that restrained the development of the test creatures was recorded as the base inhibitory focus (MIC).

Stock microdilution technique: Broth microdilution strategy was performed utilizing the philosophy like that utilized for antifungal MIC contemplates. What's more, normalization and weakenings of silver nanoparticle was done dependent on the investigation by Sultan et al., with slight changes. The MIC was resolved in LB stock utilizing a sequential two-overlay weakening of Silver nanoparticles in fixations extending from 0.062-1µg/ml. Testing was acted in a 96-well round-base microtiter plate. Cell suspensions were set up in the BHI medium and were acclimated to give a last inoculum grouping of about (0.5×103) to (2.5×103) cells/ml. At last, 10μL of the contagious suspension was added to each well. The plate was hatched at 35°C and was perused after 48 h (Candida spp). Control stocks were utilized without nanoparticles. ATCC 24433 Candida albicans are incorporated as the control creature each time with each medication. The MIC was resolved as the most reduced grouping of silver nanoAg giving no noticeable development or causing practically complete hindrance of development.

Turbidity estimation of parasitic development by utilizing spectrophotometer: This test was performed by the investigation of Sultan et al., with slight alterations. Before the test was played out, the Candida albicans segregates were newly subcultured only 1 day before the test was to be performed. Segregates were immunized in 100 ml of Luria–Bertani (LB; HiMedia) culture medium. Development was permitted until the optical thickness arrived at 0.1 at 620nm (OD=0.1, which relates to 108 CFU/ml of the medium). In this way, 2×108 CFU/ml from above was added to 100ml of fluid LB media enhanced with focuses running from 0.062-1µg/ml of AgNPs. All the carafes were put on a rotatory shaker (150 rpm) and brooded at 37°C. Control stocks were utilized without nanoparticles. Contagious development was dictated by estimating the optical thickness after each 4 h (up to 16 h) at time timespans, 4, 8, 12, 16, 20, and 24 hrs at 620 nm utilizing a spectrophotometer (VSP66, LOBA Life, India).

The genotoxicity and cytotoxicity of AgNPs are affected by a few physicochemical highlights, including scattering rate, fixation, surface charge, size, morphology, and surface functionalization. The physicochemical parts of nano silver-based frameworks and materials for the most part appropriate and order various toxicological concerns, and furthermore set up a stepping stool of harmfulness structure while forcing on the natural framework. The exploratory outcomes announced as of not long ago are deficient in regards to the exact harmful impacts of AgNPs and their related poisonousness instruments.

Silver nanoparticles (AgNPs) are seriously investigated nanostructures for eccentric and improved biomedical applications, on account of their size-related alluring physicochemical properties and organic usefulness, including their high antimicrobial proficiency and non-harmful nature. AgNP-based nanosystems and nanomaterials are reasonable choices for medicating conveyance, wound dressing, tissue platform, and defensive covering applications. Different physicochemical boundaries were identified with the inherent antimicrobial impacts showed by AgNPs, for example, size, shape, fixation, surface charge, and colloidal state. In addition, the amazing accessible surface of nanosilver permits the coordination of numerous ligands, consequently empowering colossal prospects as for the surface functionalization of AgNPs.

There is a lot of exploration information demonstrating the advantageous impacts of AgNPs in novel biocompatible and nanostructured materials and gadgets created for present-day restorative techniques. Notwithstanding their appealing and adaptable antimicrobial potential, AgNPs give extra mechanical, optical, synthetic, and organic characteristics that suggest them for the structure, getting assessment, and clinical appraisal of execution improved biomaterials and clinical gadgets. All things considered, exhaustive examinations with respect to their present moment and long haul poisonousness, just as the capable harmful related instruments, are required.

The current constraints identified with ordinary human services practice and the most recent difficulties coming about because of nano silver-based innovation layout the amazing capability of silver nanoparticles in biomedicinal applications. Regardless of whether we consider the change of accessible biomaterials and gadgets or the advancement of novel nanostructured ones, AgNPs are perfect possibility for accomplishing the nearby current biomedicine goal.