Am J Clin Microbiol Antimicrob | Volume 1, Issue 3 | Research Article | Open Access
Madhuri Singh#, Tahsina Shireen# and Kasturi Mukhopadhyay*#
School of Environmental Sciences, Jawaharlal Nehru University, India #All the authors contributed equally
*Correspondance to: Kasturi Mukhopadhyay
Fulltext PDFAntimicrobial Peptides (AMPs) are one of the most promising future strategies for defeating the antibiotic resistance. Alpha Melanocyte Stimulating Hormone (α-MSH) is a cationic neuropeptide and we have previously reported its strong in vitro antimicrobial activity against Staphylococcus aureus. However, the efficacy of this peptide needs to be tested against a large number of clinical S. aureus isolates to ascertain its antistaphylococcal potential. Moreover, in vivo efficacy of alpha- MSH need to be determined for establishing its biological significance. In the present study, we tested the susceptibility of a total of 100 clinical S. aureus isolates, including 43 MSSA and 57 MRSA towards α-MSH and found that 10 μg/ml of α-MSH killed 95% and 77% of MSSA and MRSA strains, respectively. To check if cross resistance existed among the α-MSH-non-susceptible strains, a susceptibility profiling test was done towards three other AMPs belonging to different sources. We chose gramicidin D, magainin 2 and human neutrophil peptide 1 for this purpose and it was observed that cross resistance was not present among the study strains. We further evaluated in vivo efficacy of α-MSH against S. aureus using mice intravenous and skin wound infection models. Results revealed that the therapeutic efficacy of α-MSH at 8 mg/kg is superior to that of oxacillin in animal infection model, leading to 100% survival of the S. aureus infected animals. The effectiveness of α-MSH both in vitro and in vivo models further strengthened the clinical potential of this peptide.
S. aureus; α-MSH; Antimicrobial peptides; In vivo; Mice model
Singh M, Shireen T, Mukhopadhyay K. Susceptibility of Clinical Isolates of Staphylococcus aureus to Alpha- Melanocyte Stimulating Hormone and Its In Vivo Efficacy. Am J Clin Microbiol Antimicrob. 2018; 1(3): 1014.