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.