6.2 - α-MSH and viral infections
Limited data is currently available regarding the role of α-MSH in viral infections. Most studies have primarily focused on conducting in vitro experiments and analyzing circulating levels of α-MSH in humans during viral infections. However, to date, there have been no studies that definitively demonstrate the pro-resolutive effect of α-MSH treatment in mouse models of viral infections or in human clinical studies. Nevertheless, certain findings have indicated that systemic levels of α-MSH were higher in HIV patients compared to controls. Notably, an association was observed between elevated levels of α-MSH and reduced levels of IL-6, as well as a decrease in disease progression (Catania et al., 1993; Airaghi et al., 1999; Catania et al., 1994). Furthermore, α-MSH-derived peptides were found to decrease HIV replication in monocytic cell lineages (Barcellini et al., 2000). In addition, α-MSH demonstrated a reduction in the production of IL-1β and TNF induced by the viral protein gp120 in whole blood samples obtained from HIV patients (Catania et al., 1998b). However, the specific receptors through which α-MSH mediates these mechanisms remain unknown, despite its promising in vitro effects against HIV.