title: Application of S-thanatin, an antimicrobial peptide derived from thanatin, in mouse model of Klebsiella pneumoniae infection.
abstract: Thanatin was first discovered from the hemipteran insect Podisus maculiventris and showed a promising antimicrobial activity. Multidrug-resistant (MDR) clinical isolates of Klebsiella pneumoniae have developed resistance to current therapies. As an attempt to resolve this problem, the efficacy of thanatin and its analogues against clinical isolates of K. pneumoniae was studied in vitro and in vivo. S-thanatin showed an improved antimicrobial activity with the tested MIC values was 2-8-fold lower than those of other thanatin analogs. Antimicrobial assay indicated a high activity of S-thanatin against K. pneumoniae in vitro with MIC between 4 and 8 μg/ml. Its in vivo activity was evaluated using a K. pneumoniae-infected mice model. Adult male ICR mice were randomly grouped and given an intraperitoneal (i.p.) administration of 2 × 10(10)colony-forming units of K. pneumoniae (CI 120204205). Afterwards, mouse groups were subjected to i.p. administration of saline or S-thanatin (5, 10, or 15 mg/kg). After an inspection of 72 h, the mice were finally sacrificed for analysis of in vivo bacterial growth and plasma endotoxin level. The results showed that S-thanatin administration apparently improved the survival rate and reduced the bacterial CFU from intra-abdominal fluid in mice. The plasma endotoxin level was improved as well. All above implied that S-thanatin, as an alternative, may provide a novel strategy for treating K. pneumoniae infection and other infections due to multidrug-resistant bacteria.
authors: Center of Clinical Laboratory Medicine of Zhongda Hospital, Southeast University, Nanjing 210009, China. guoqiu_wu@hotmail.com
authors: Guoqiu
authors: G
authors: Wu
authors: Pengpeng
authors: P
authors: Wu
authors: Xiulei
authors: X
authors: Xue
authors: Xuejiao
authors: X
authors: Yan
authors: Siru
authors: S
authors: Liu
authors: Chen
authors: C
authors: Zhang
authors: Zilong
authors: Z
authors: Shen
authors: Tao
authors: T
authors: Xi
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D023181:Antimicrobial Cationic Peptides / Q000494:pharmacology*; D015169:Colony Count, Microbial; D004305:Dose-Response Relationship, Drug; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D004731:Endotoxins / Q000037:antagonists & inhibitors / Q000097:blood; D007274:Injections, Intraperitoneal; D007710:Klebsiella Infections / Q000188:drug therapy* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000254:growth & development; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008826:Microbial Sensitivity Tests; D018410:Pneumonia, Bacterial / Q000188:drug therapy* / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D004731:Endotoxins; C098076:thanatin