Obesity is often associated with cognitive and mood disorders. Recent evidence suggests that obesity may cause hypothalamic inflammation. Our aim was to investigate the hypothesis that there is a causal link between obesity-induced hypothalamic inflammation and cognitive and mood disorders. Inflammation may influence hypothalamic inter-connections with regions important for cognition and mood, while it may cause dysregulation of the Hypothalamic-Pituitary-Adrenal (HPA) axis and influence monoaminergic systems. Exercise, healthy diet, and glucagon-like peptide receptor agonists, which can reduce hypothalamic inflammation in obese models, could improve the deleterious effects on cognition and mood.

Critical illness (CI) triggers complex disruptions in the growth hormone (GH)/insulin-like growth factor (IGF) axis, significantly affecting the dynamics of insulin-like growth-factor-binding proteins (IGFBPs). Among these, IGFBP-2 shows a sustained elevation during CI, which inversely correlates with serum levels of IGF-1, IGFBP-3, and the acid-labile subunit (ALS). Although IGFBP-2 does not directly interact with ALS, it may influence the availability of IGFs by competing with other IGFBPs for binding to IGF-1 and IGF-2. Research suggests that this persistent elevation of IGFBP-2 is largely driven by cytokine activity during CI, reflecting an adaptive response rather than a direct result of GH/IGF axis dysregulation. The clinical importance of IGFBP-2 is emphasized by its correlation with disease severity in conditions like sepsis and coronavirus disease 2019 (COVID-19), where its levels are markedly elevated compared to healthy controls and are similar to those observed in sepsis from various causes. Beyond its role in endocrine regulation, IGFBP-2 appears to play a part in metabolic and inflammatory pathways. Elevated IGFBP-2 levels have been linked to increased mortality and longer hospital stays, indicating its potential utility as a prognostic marker. Furthermore, measuring plasma IGFBP-2 may have other diagnostic applications, aiding in the assessment of CI when traditional biomarkers are inconclusive.