HMGB1 in nasal inflammatory diseases: a reappraisal 30 years after its discovery

Introduction: High mobility group protein box 1 (HMGB1) is a protein belonging to the alarmin family. HMGB1 has a relevant role in starting the inflammatory cascade by means of receptors, such as RAGE and TLR. HMGB1 supports transcription of many genes in interactions with many transcription factors, including NF-kB. The axis HMGB1-RAGE-NF-kB has, therefore, a pivotal role in the inflammatory cascade. HMGB1 controls the production of several pro-inflammatory cytokines and the proliferation and activation of many inflammatory cells. Areas covered: The present report concerns the role of HMGB1 in nasal inflammatory disorders, including allergic and non-allergic rhinitis, and chronic rhinosinusitis with nasal polyps. HMGB1 modulation has been the aim of several studies. The literature search included recent papers that covered this topic. Expert opinion: As HMGB1 has a pivotal role in inflammatory events, its modulation could be attractive for designing new therapeutic strategies. In this regard, glycyrrhetic acid (GA), the active component of Glycyrrhiza glabra, can efficiently block HMGB1. Promising reports seem to suggest that GA could exert favorable anti-inflammatory activity in patients with nasal inflammatory disorders.