Citrate reduced gold nanoparticles lowered lipid content in differentiated 3T3-L1 adipocytes by altering the expression of adipogenic genes

Abstract

Obesity and related metabolic disorders are increasing at alarming rates worldwide, posing a major public health challenge. Current anti-obesity therapies are limited by toxicity and adverse side effects, highlighting the need for alternative strategies. Nanotechnology offers a promising approach, with gold nanoparticles (AuNPs) attracting significant attention in biomedical applications due to their unique physicochemical properties and potential therapeutic effects. This study investigated the anti-lipogenic effects of citrate-capped AuNPs (cAuNPs) on differentiated 3T3-L1 adipocytes. The 14 nm cAuNPs were synthesized using the citrate reduction method and characterized using UV-vis spectroscopy, dynamic light scattering (DLS), and transmission electron microscopy (TEM). The effects of cAuNPs were evaluated on cell viability, lipid accumulation, and gene expression in 3T3-L1 cells and differentiated 3T3-L1 adipocytes. cAuNPs were non-cytotoxic to 3T3-L1 cells at concentrations up to 400 nM. Oil Red O (ORO) staining revealed a concentration-dependent reduction in lipid accumulation, with the maximal effect at 72 h. Gene expression analysis using RT 2 PCR arrays identified 35 differentially expressed genes, with significant alterations in genes related to adipogenesis and lipid metabolism. Functional enrichment and protein–protein interaction (PPi) network analyses highlighted modulation of PPAR signalling and key hub genes involved in adipocyte function. These findings demonstrated that cAuNPs exert anti-adipogenic effects by altering molecular pathways associated with lipid storage, suggesting their potential as a nanotechnology-based strategy for obesity management. Future in vivo studies will be essential to assess their therapeutic efficacy and safety in order to advance AuNPs as innovative anti-obesity agents.