Anti-Inflammatory, Anti-Obesity, and Insulin-Sensitizing Effects of Chamaecrista nomame (Siebold) H. Ohashi Extract...

Chamaecrista nomame (Siebold) H. Ohashi (C. nomame), a leguminous plant traditionally consumed in East Asia, contains diverse bioactive phytochemicals, but whether its activities act convergently under obesity-related pathological conditions remains unclear. This study investigated the anti-inflammatory, anti-obesity, and insulin-sensitizing effects of a 40% ethanol extract of C. nomame (ECNE) and its marker compound luteolin in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages, differentiating and mature 3T3-L1 adipocytes, and tumor necrosis factor-α (TNF-α)-induced insulin-resistant adipocytes. In LPS-stimulated macrophages, ECNE and luteolin reduced nitric oxide and pro-inflammatory cytokine (TNF-α, interleukin (IL)-6, IL-1β) production, accompanied by suppression of nuclear factor-κB and mitogen-activated protein kinase signaling. In differentiating adipocytes, both reduced lipid accumulation and downregulated peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding protein α, and adipocyte protein 2. In mature adipocytes, they enhanced insulin-stimulated glucose uptake and Akt phosphorylation. In TNF-α-challenged adipocytes, pretreatment partially restored glucose uptake and Akt phosphorylation while attenuating IL-6 and monocyte chemoattractant protein-1 production. ECNE exerted effects equal to or greater than those of luteolin at equivalent luteolin-based concentrations, indicating contributions from additional phenolic constituents. These findings support ECNE as a multifunctional natural resource against obesity-associated inflammation and insulin resistance.