Perilla frutescens var. acuta (Lamiaceae) is widely used not only as an oil or a spice, but also as a traditional medicine to treat colds, coughs, fever, and indigestion. As an ongoing effort, luteolin-7-O-diglucuronide (1), apigenin-7-O-diglucuronide (2), and rosmarinic acid (3) isolated from P. frutescens var. acuta were investigated for their anti-adipogenic and thermogenic activities in 3T3-L1 cells. Compound 1 exhibited a strong inhibition against adipocyte differentiation by suppressing the expression of Pparg and Cebpa over 52.0% and 45.0%, respectively. Moreover, 2 inhibited the expression of those genes in a dose-dependent manner [Pparg: 41.7% (5 µM), 62.0% (10 µM), and 81.6% (50 µM); Cebpa: 13.8% (5 µM), 18.4% (10 µM), and 37.2% (50 µM)]. On the other hand, the P. frutescens var. acuta water extract showed moderate thermogenic activities. Compounds 1 and 3 also induced thermogenesis in a dose-dependent manner by stimulating the mRNA expressions of Ucp1, Pgc1a, and Prdm16. Moreover, an LC-MS/MS chromatogram of the extract was acquired using UHPLC-MS² and it was analyzed by feature-based molecular networking (FBMN) and the Progenesis QI software (version 3.0). The chemical profiling of the extract demonstrated that flavonoids and their glycoside derivatives, including those isolated earlier as well as rosmarinic acid, are present in P. frutescens var. acuta.

Isoegomaketone [(E)-1-(furan-3-yl)-4-methylpent-2-en-1-one; 1] is abundant in the essential oil of Perilla species and exhibits various biological activities, such as anticancer and anti-inflammatory effects. In order to discover compounds with reduced toxicity or enhanced biological activity through structural modification of natural product-derived components, isoegomaketone was irradiated with an electron beam at five different doses, and (±)-8-methoxy-perilla ketone (2) was obtained with the highest yield of 3.8% (w/w) at 80 kGy. Its structure was identified by one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy and high-resolution chemical ionization mass spectrometry. Compound 2 inhibited nitric oxide production and inducible nitric oxide synthase mRNA expression in a dose-dependent manner in lipopolysaccharide-stimulated RAW 264.7 cells. It also dose-dependently suppressed the mRNA expression of pro-inflammatory mediators such as IL-1β, IFN-β, and MCP-1, while having no significant effect on IL-6 mRNA levels. Furthermore, ELISA analysis demonstrated that 2 reduced MCP-1 protein expression but did not affect the protein level of TNF-α or IL-6. This study provides a reference for the structural analysis of compounds related to 2 by presenting NMR data acquired with chloroform-d, and is the first to report the anti-inflammatory properties of 2.