Brown Algae Ecklonia cava Extract Modulates Adipogenesis and Browning in 3T3-L1 Preadipocytes through HO-1/Nrf2 Signaling

Abstract

This study explores the anti-obesity effects of the ethyl acetate extract of Ecklonia cava (EC-ETAC) on 3T3-L1 preadipocytes, focusing on its impact on adipogenesis, lipolysis, and adipose browning via the HO-1/Nrf2 pathway. Western blot analysis revealed that EC-ETAC significantly inhibited adipogenic transcription factors (PPARγ, C/EBPα, SREBP-1) and lipogenesis-related proteins (FAS, LPL). Concurrently, EC-ETAC enhanced lipolytic markers (p-AMPK, p-HSL) and adipose browning-related proteins (UCP-1, PGC-1α), indicating its role in promoting lipolysis and adipose browning. The inhibition of HO-1 by zinc protoporphyrin (ZnPP) significantly reversed these effects, underscoring the critical role of HO-1 in mediating the anti-obesity properties of EC-ETAC. Additionally, fluorescence measurements and Oil Red O staining confirmed the reduction of lipid accumulation and oxidative stress upon EC-ETAC treatment. These findings suggest that EC-ETAC exerts its anti-obesity effects by modulating the HO-1/Nrf2 pathway, which is crucial for regulating adipogenesis, lipolysis, and adipose browning. This study highlights the potential of EC-ETAC as a natural therapeutic agent for obesity management and supports further research into its clinical applications. By targeting the HO-1/Nrf2 pathway, EC-ETAC could offer a novel approach to enhancing energy expenditure and reducing fat mass, thereby improving metabolic health.