The Anti-Adipogenic Activity of a New Cultivar, Pleurotus eryngii var. ferulae 'Beesan No. 2', through Down-Regulation of PPAR γ and C/EBP α in 3T3-L1 Cells.

Adipogenesis is one of the cellular processes and a highly controlled program. Nowadays, inhibition of adipogenesis has received attention as an effective way to regulate obesity. In the current study, we investigated the inhibition effect of a chloroform extract of Pleurotus eryngii var. ferulae 'Beesan No. 2' (CEBT) on adipogenesis in 3T3-L1 murine preadipocytes. Pleurotus eryngii var. ferulae is one of many varieties of King oyster mushroom and has been reported to have various biological activities, including antitumor and anti-inflammation effects. Biological activities of 'Beesan No. 2', a new cultivar of Pleurotus eryngii var. ferulae, have not yet been reported. In this study, we found that CEBT suppressed adipogenesis in 3T3-L1 cells through inhibition of key adipogenic transcription factors, such as peroxisome proliferator-activated receptor γ and CCAAT/enhancer binding protein α. Additionally, CEBT reduced the expression of the IRS/PI3K/Akt signaling pathway and its downstream factors, including mammalian target of rapamycin and p70S6 kinase, which stimulate adipogenesis. Furthermore, ß-catenin, a suppressor of adipogenesis, was increased in CEBT-treated cells. These results indicate that Pleurotus eryngii var. ferulae 'Beesan No. 2' effectively inhibited adipogenesis, so this mushroom has potential as an anti-obesity food and drug.

Gene cloning and characterization of MdeA, a novel multidrug efflux pump in Streptococcus mutans.

Multidrug resistance, especially multidrug efflux mechanisms that extrude structurally unrelated cytotoxic compounds from the cell by multidrug transporters, is a serious problem and one of the main reasons for the failure of therapeutic treatment of infections by pathogenic microorganisms as well as of cancer cells. Streptococcus mutans is considered one of the primary causative agents of dental caries and periodontal disease, which comprise the most common oral diseases. A fragment of chromosomal DNA from S. mutans KCTC3065 was cloned using Escherichia coli KAM32 as host cells lacking major multidrug efflux pumps. Although E. coli KAM32 cells were very sensitive to many antimicrobial agents, the transformed cells harboring a recombinant plasmid became resistant to several structurally unrelated antimicrobial agents such as tetracycline, kanamycin, rhodamin 6G, ampicillin, acriflavine, ethidium bromide, and tetraphenylphosphonium chloride. This suggested that the cloned DNA fragment carries a gene encoding a multidrug efflux pump. Among 49 of the multidrug-resistant transformants, we report the functional gene cloning and characterization of the function of one multidrug efflux pump, namely MdeA from S. mutans, which was expressed in E. coli KAM32. Judging from the structural and biochemical properties, we concluded that MdeA is the first cloned and characterized multidrug efflux pump using the proton motive force as the energy for efflux drugs.

Soraphinol C, a new free-radical scavenger from Sorangium cellulosum.

A new compound named soraphinol C (1) was isolated from myxobacteria Sorangium cellulosum KM1001 a soil isolate, together with a structurally related known compound, 4-hydroxysattabacin (2). These compounds were isolated by silica gel column chromatography and recycling preparative HPLC, consecutively. The structures of the compounds were determined on the basis of combined spectroscopic analyses. Compounds 1 and 2 exhibited antioxidant activity as a radical scavenger in the experiment using a hydrophilic free-radical initiator, 2,2'-azobis(2-amidinopropane)dihydrochloride with ORAC values of 0.956 and 0.617, respectively.