Context: Nerve growth factor (NGF) affects the development and survival of sympathetic neurons. NGF is also found in non-neural cell lineages that are implicated in immune-endocrine interactions associated with metabolic diseases. Although NGF is expressed in white adipose tissue (WAT), little is known about the regulation of its expression and role in adipocytes. Objective: To determine whether NGF and its receptors are expressed in human adipocytes and demonstrate their role in adipocyte metabolic and inflammatory phenotypes. Methods: The expression of NGF and its receptors, tropomyosin-related kinase A (TrkA) and pan-neurotrophin receptor (p75NTR), and their effects on metabolic and inflammatory responses were examined in freshly isolated adipocytes from human abdominal WAT and mouse 3T3L1 cells. Results: TrkA and p75NTR were expressed in both human and mouse adipocytes and pre-adipocytes. NGF was secreted by human white adipocytes and their exogenous exposure to NGF increased mitochondrial mass and activity, peroxisome proliferator-activated receptor gamma, CCAAT/enhancer binding protein alpha, and adiponectin levels. Additionally, NGF increased lipolysis in human WAT explants and suppressed lipids accumulation, lipoprotein lipase, and pro-inflammatory mediators interleukin (IL)-6 and IL-8 in human white adipocytes. The pro-inflammatory factor lipopolysaccharide downregulated the levels of NGF receptors in human white adipocytes. NGF also affected mitochondrial activity in both human and mouse pre-adipocytes and TrkA appeared to mediate, at least partially, the effects of NGF on adipocytes. Conclusion: Our data suggest that NGF is produced locally within the adipose tissue where it upregulates mitochondrial function while it suppresses the pro-inflammatory phenotype of human and mouse adipocytes.

Background/Objectives: Psoriasis is a chronic, systemic, and multifactorial disease affecting approximately 1–2% of the Caucasian population. It is characterized by distinct histopathological features, including epidermal hyperplasia and infiltration of immune cells into the skin. Despite its high prevalence, the underlying mechanisms driving psoriasis remain incompletely understood. Heat shock proteins (HSPs), particularly HSP70, are known to play key roles in modulating immune responses and inflammation. Although previous studies have examined the involvement of HSPs in dermatological conditions such as psoriasis, current evidence remains inconclusive. In this study, we aimed to elucidate the role of Hsp70 deficiency in the pathogenesis of psoriasis using an in vivo model. Methods: We used male mice that were either genetically normal (Hsp70+/+) or lacked the Hsp70 gene (Hsp70−/−) at 8–12 weeks of age. Psoriasis was induced by applying imiquimod cream daily for 7 days. At the end of this period mice were sacrificed and blood and tissue collected for further analysis. The severity of the psoriasis was evaluated daily using the PASI Score. Results: Hsp70 depletion was accompanied by significantly decreased psoriatic-like skin inflammation, fewer histological abnormalities, and lower PASI scores. Flow cytometry analysis revealed a decrease in LY6C⁺ monocytes and an increase in LY6G⁺ neutrophils infiltration in Hsp70-deficient mice. In addition, HSP60 expression was lower in the absence of HSP70, while HSP90 expression was markedly elevated. Conclusions: These results point to a significant regulatory function of HSP70 in psoriatic inflammation and raise the possibility that it could be a therapeutic target.