Browning of white adipose tissue is a novel approach for the management of obesity and obesity-related metabolic disorders. Kaempferol (KPF) is a common dietary nutrient found abundantly in many fruits and vegetables and has been shown to have the potential to regulate lipid metabolism. However, the detailed mechanism by which it affects the browning of white adipose tissue remains unclear. In the present study, we sought to determine how KPF induces adipocytes to undergo a browning transformation by establishing a primary adipocyte model and an obese mouse model. Our results showed that KPF-treated mice were rescued from diet-induced obesity, glucose tolerance and insulin resistance, associated with increased expression of adaptive thermogenesis-related proteins. KPF-promoted white adipose browning correlated with the AMPK/SIRT1/PGC-1α pathway, as the use of an AMPK inhibitor in preadipocytes partially reversed the observed browning phenotype of KPF-treated cells. Taken together, these data suggest that KPF promotes browning of white adipose tissue through activation of the AMPK/SIRT1/PGC-1α pathway. This study demonstrates that KPF is a promising natural product for the treatment of obesity by promoting white fat browning.

ETHNOPHARMACOLOGICAL RELEVANCE:Modified sanmiao pills (MSMP), a traditional Chinese medicine (TCM) formula, is consisted of rhizome of Smilax glabra Roxb., Cortexes of Phellodendron chinensis Schneid., rhizome of Atractylodes chinensis (DC.) Koidz., and roots of Cyathula officinalis Kuan. in a ratio of 3:3:2:1. This formula has been broadly applied to treat gouty arthritis (GA) in China. AIMS OF THE STUDY:To elaborate the pharmacodynamic material basis and pharmacological mechanism of MSMP against GA. MATERIALS AND METHODS:UPLC-Xevo G2-XS QTOF combined with UNIFI platform was applied to qualitatively assess the chemical compounds of MSMP. Network pharmacology and molecular docking were used to identify the active compounds, core targets and key pathways of MSMP against GA. The GA mice model was established by MSU suspension injecting into ankle joint. The swelling index of ankle joint, expressions of inflammatory cytokines, and histopathological changes in mice ankle joints were determined to validate the therapeutic effect of MSMP against GA. The protein expressions of TLRs/MyD88/NF-κB signaling pathway and NLRP3 inflammasome in vivo was detected by Western blotting. RESULTS:In total, 34 chemical compounds and 302 potential targets of MSMP were ascertained, of which 28 were overlapping targets pertaining to GA. 143 KEGG enrichment pathway were obtained, of which the NOD-like receptor signaling pathway, Toll-like receptor signaling pathway, and NF-κB signaling pathway were strongly associated with GA. In silico study indicated that the active compounds had excellent binding affinity to core targets. In vivo study confirmed that MSMP observably decreased swelling index and alleviated pathological damage to ankle joints in acute GA mice. Besides, MSMP significantly inhibited the secretion of inflammatory cytokines (IL-1β, IL-6, and TNF-α) induced by MSU, as well as the expression levels of key proteins involved in TLRs/MyD88/NF-κB signaling pathway and NLRP3 inflammasome. CONCLUSION:MSMP possessed a pronounced therapeutic effect on acute GA. Results from network pharmacology and molecular docking showed that obaculactone, oxyberberine, and neoisoastilbin might treat gouty arthritis by down-regulating TLRs/MyD88/NF-κB signaling pathway and NLRP3 inflammasome.

目的 运用网络药理学和分子对接技术预测黄精防治痛风的有效成分作用靶点及通路。方法 利用TCMSP和Drugbank数据库获取黄精活性成分及作用靶点，利用TTD、OMIM和GeneCards数据库获得痛风相关靶点，将两者输入Venny 2.1中筛选得到黄精治疗痛风的核心靶点。通过Cytoscape 3.8.0软件构建“中药-成分-靶点-疾病”网络模型，S TRING数据库构建PPI网络，Metascape数据库进行GO与KEGG通路富集分析，并用Autodock＿vina软件进行分子对接研究。最后，通过LPS结合MSU诱导RAW264.7细胞模拟体外痛风模型，并对预测结果进行验证。结果 预测共得到13种活性成分、90个潜在靶点、1 139个痛风相关疾病靶点，19个黄精-痛风交集靶点，涉及MAPK14、CAT、PPARG、NOS2、VEGFA等，并推断其作用机制可能与PI3K-Akt信号通路、血小板激活信号通路、钙信号通路和雌激素信号通路等有关。分子对接结果表明，活性成分与核心靶点的结合能在–10.4～–4.6kcal·mol -1 ，具有较好的结合能力。细胞实验显示，薯蓣皂苷元能够降低p38MAPK及其上游ERK1/2磷酸化蛋白的表达。结论 黄精防治痛风的生物学机制可能与其调控核心靶点MAPK14有关。