Porphyra dentata, an edible red macroalgae, is used as a folk medicine in Asia. This study evaluated in vitro and in vivo the protective effect of a sterol fraction from P. dentata against breast cancer linked to tumor-induced myeloid derived-suppressor cells (MDSCs). A sterol fraction containing cholesterol, β -sitosterol, and campesterol was prepared by solvent fractionation of methanol extra...

Starr, Patricia R. (Oregon State University, Corvallis) and L. W. Parks. Some factors affecting sterol formation in Saccharomyces cerevisiae. J. Bacteriol. 83:1042-1046. 1962.-A wild-type diploid strain of Saccharomyces cerevisiae was used in a study of factors that influence sterol synthesis. Maltose, glucose, sodium acetate, and ethanol were shown to be readily available for sterol synthesis ...

Sterol ratios are used to identify sources, occurrence and partitioning of faecal matter in sediments of the Tay Estuary, Scotland. The 5β/(5α+5β) ratio is used to discriminate between sewage and biogenic sterol sources by comparing the concentrations of coprostanols to cholesterol plus coprostanols. This index shows unambiguous sewage pollution in the Invergowrie Bay area (values >0.7). The co...

BACKGROUND Consumption of plant sterols and plant stanols reduces low-density lipoprotein cholesterol (LDL-C) concentrations. At the same time, plasma plant sterol concentrations will increase after plant sterol consumption, but decrease after plant stanol consumption. In contrast to plant stanols, plant sterols can undergo oxidation and form oxyphytosterols. Findings from in vitro and animal s...

Effects of dietary unesterified plant sterols and plant sterol oleates and stearates on absorption and metabolism of cholesterol were compared in rats fed a cholesterol-supplemented diet. Fecal excretion of neutral steroids (cholesterol plus coprostanol) in rats fed unesterified plant sterols or plant sterol oleates was significantly higher than in those fed the control diet or plant sterol ste...

Through substitution mutagenesis and gene transfer experiments in cultured cells, we have identified three sequences in the 5' flanking region of the gene for hamster 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) synthase that are required for sterol-mediated regulation of transcription. Point mutations in any one of these sequences largely prevented the increase in transcription that normall...

In Saccharomyces cerevisiae, the Rho-type GTPase Cdc42 regulates polarized growth through its effectors, including the p21-activated kinases (PAKs) Ste20, Cla4, and Skm1. Previously, we demonstrated that Ste20 interacts with several proteins involved in sterol synthesis that are crucial for cell polarization. Under anaerobic conditions, sterols cannot be synthesized and need to be imported into...

In this study, the sterol contents of almond kernel oils collected from naturally growing almond trees in Mersin province were determined. Generally, the sterol contents of almond oil samples varied depending on almond types. The major sterols in almond oils wereß-sitosterol, 5-avenasterol and campesterol, followed by 5,24-stigmastadienol, stigmasterol, sitostanol, and cholesterol. W...

Cholesterol is an essential component of mammalian cell membranes and is required for proper membrane permeability, fluidity, organelle identity, and protein function. Cells maintain sterol homeostasis by multiple feedback controls that act through transcriptional and posttranscriptional mechanisms. The membrane-bound transcription factor sterol regulatory element binding protein (SREBP) is the...

In Saccharomyces cerevisiae, the Rho-type GTPase Cdc42 regulates polarized growth through its effectors, including the p21-activated kinases (PAKs) Ste20, Cla4 and Skm1. Previously, we demonstrated that Ste20 interacts with several proteins involved in sterol synthesis that are crucial for cell polarization. Under anaerobic conditions, sterols cannot be synthesized and need to be imported into ...