8.3 Ang-(1-7) and bacterial infections
In the context of bacterial infection, treatment with Ang-(1-7) has shown promising benefits in reducing lung bacterial load, sepsis, and mortality associated with pneumococcal infection following Influenza A virus infection (Melo et al., 2021). Another significant finding of Ang-(1-7) is its ability to restore the phagocytic capacity of neutrophils in mice with experimental Type 2 Diabetes Mellitus, enabling them to effectively phagocytize bacteria such as Staphylococcus aureus , which is known to cause lung infections (Soto et al., 2019). In the context of bacterial infection, Ang-(1-7) has also been found to suppress macrophage polarization towards the M1 phenotype and promote a shift towards the M2 phenotype in a model of polymicrobial sepsis induced by cecal ligation and puncture (CLP). This modulation of macrophage phenotype reduces excessive inflammation (Pan et al., 2021). Additionally, in the same CLP model, Ang-(1-7) has been shown to attenuate mortality by mitigating the exaggerated inflammatory response, oxidative stress, and apoptosis (Tsai et al., 2018). These results highlight the protective effects of Ang-(1-7) against infections and emphasize that modulation of the RAS can be beneficial in promoting the resolution of inflammation associated with infections.
Conclusion
Pro-resolving molecules modulate a range of pathways associated with tissue inflammation and damage during viral and bacterial infections and provide overall beneficial effects and earlier control of infection and restoration of tissue homeostasis. These beneficial effects in inflammation without altering the ability of the host to deal with infection are the basis for the development of pro-resolving molecules or their mimetics as co-adjuvant treatment of infection. In addition, these molecules appear to provide anti-inflammatory, pro-resolving and, at times, anti-infective benefit, without the known undesirable and immunosuppressive effects of glucocorticoids.