Silver-loaded nanotubular structures enhanced bactericidal efficiency of antibiotics with synergistic effect in vitro and in vivo.
Antibiotic-resistant bacteria have become a major issue due to the long-term use and abuse of antibiotics in treatments in clinics. The combination therapy of antibiotics and silver (Ag) nanoparticles is an effective way of both enhancing the antibacterial effect and decreasing the usage of antibiotics. Although the method has been proved to be effective in vitro, no in vivo tests have been carried out at present. Herein, we described a combination therapy of local delivery of Ag and systemic antibiotics treatment in vitro in an infection model of rat. Ag nanoparticle-loaded TiO2nanotube (NT) arrays (Ag-NTs) were fabricated on titanium implants for a customized release of Ag ion. The antibacterial properties of silver combined with antibiotics vancomycin, rifampin, gentamicin, and levofloxacin, respectively, were tested in vitro by minimum inhibitory concentration (MIC) assay, disk diffusion assay, and antibiofilm formation test. Enhanced antibacterial activity of combination therapy was observed for all the chosen bacterial strains, including gram-negativeEscherichia coli(ATCC 25922), gram-positiveStaphylococcus aureus(ATCC 25923), and methicillin-resistantStaphylococcus aureus(MRSA; ATCC 33591 and ATCC 43300). Moreover, after a relative short (3 weeks) combinational treatment, animal experiments in vivo further proved the synergistic antibacterial effect by X-ray and histological and immunohistochemical analyses. These results demonstrated that the combination of Ag nanoparticles and antibiotics significantly enhanced the antibacterial effect both in vitro and in vivo through the synergistic effect. The strategy is promising for clinical application to reduce the usage of antibiotics and shorten the administration time of implant-associated infection.
The State Key Laboratory of Refractories and Metallurgy, School of Materials and Metallurgy, Wuhan University of Science and Technology; Institute of Biology and Medicine, Wuhan University of Science and Technology.
Na
N
Xu
Orthopaedic Department, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China; Biomaterials Innovation Research Center, Division of Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Hao
H
Cheng
The State Key Laboratory of Refractories and Metallurgy, School of Materials and Metallurgy, Wuhan University of Science and Technology.
Jiangwen
J
Xu
Orthopaedic Department, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Feng
F
Li
The State Key Laboratory of Refractories and Metallurgy, School of Materials and Metallurgy, Wuhan University of Science and Technology.
Biao
B
Gao
Orthopaedic Department, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Zi
Z
Li
Orthopaedic Department, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Chenghao
C
Gao
Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Kaifu
K
Huo
The State Key Laboratory of Refractories and Metallurgy, School of Materials and Metallurgy, Wuhan University of Science and Technology; Institute of Biology and Medicine, Wuhan University of Science and Technology.
Jijiang
J
Fu
Orthopaedic Department, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
Wei
W
Xiong
D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D007124:Immunoenzyme Techniques; D066298:In Vitro Techniques; D007249:Inflammation / Q000188:drug therapy*; D008297:Male; D008826:Microbial Sensitivity Tests; D053758:Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D043942:Nanotubes / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012834:Silver / Q000737:chemistry*
D000900:Anti-Bacterial Agents; D012834:Silver
TiO2 nanotube; antibiotics; implant-associated infection; silver nanoparticles; synergistic bactericidal activity