The frequent occurrence of multidrug-resistant strains to conventional antimicrobials has led to a clear decline in antibiotic therapies. Therefore, new molecules with different mechanisms of action are extremely necessary. Due to their unique properties, antimicrobial peptides (AMPs) represent a valid alternative to conventional antibiotics and many of them have been characterized for their activity and cytotoxicity. However, the effects that these peptides cause at concentrations below the minimum growth inhibitory concentration (MIC) have yet to be fully analyzed along with the underlying molecular mechanism. In this mini-review, the ability of AMPs to synergize with different antibiotic classes or different natural compounds is examined. Furthermore, data on microbial resistance induction are reported to highlight the importance of antibiotic resistance in the fight against infections. Finally, the effects that sub-MIC levels of AMPs can have on the bacterial pathogenicity are summarized while showing how signaling pathways can be valid therapeutic targets for the treatment of infectious diseases. All these aspects support the high potential of AMPs as lead compounds for the development of new drugs with antibacterial and immunomodulatory activities.

常规抗生素对多药耐药菌株的频繁出现导致抗生素治疗的明显下降。因此，非常需要具有不同作用机理的新分子。由于其独特的性能，抗菌肽（AMPs）代表了常规抗生素的有效替代品，其中许多抗菌肽的活性和细胞毒性得到了表征。但是，这些肽在低于最小生长抑制浓度（MIC）的浓度下所引起的影响以及潜在的分子机理尚未得到充分的分析。在此小型审查中，我们研究了AMP与不同抗生素类别或不同天然化合物协同作用的能力。此外，据报道有关微生物抗药性的数据突出了抗生素抗药性在对抗感染中的重要性。最后，总结了AMP的亚MIC水平可能对细菌致病性的影响，同时显示了信号通路如何成为治疗传染病的有效治疗靶标。所有这些方面都支持AMPs作为先导化合物具有开发具有抗菌和免疫调节活性的新药的巨大潜力。