Abstract

Objective: In previous studies, we evaluated antibacterial activity of CM11 peptide against multiple drug resistant clinical isolates of six bacteria species, alone and in combination with conventional antibiotics. Although antimicrobial peptides like CM11 peptide are one of the best new alternative antibiotics, the side effects such as toxicity are major problem. Previously the in vitro cytotoxic effects of the peptide, viability of some cell lines have been investigated. Methods: For in vivo studies, the present study is conducted to obtain more clarification about the toxicity and histopathological effects of peptide in mice. For this purpose three groups of mice were treated with different concentrations (0.2, 2.5, and 7.5 mg/kg) of peptide and then histological study for the liver, kidney and jejunum and aspartate and alanine aminotransferase activities and total serum bilirubin and albuminin blood plasma levels were measured. Results: Our study showed that the activities of aminotransferase, also total serum bilirubin and albumin levels were not significantly increased while different histological changes were observed in organs’ tissue. These changes were dependent on peptide concentration so that an increase in focal inflammation was observed with increasing peptide concentration; however these histological changes are not considerable in lower concentration. Conclusion: Our findings showed that although in comparison with the control group, markers level is normal but damages were visible in the tissues, as increase in the level of tissue damages has not led to increased levels of markers. It seems that the lack of correlation between tissue damage and level of liver markers probably is related to the level of damage. © 2017 Bentham Science Publishers.