title: Dietary crystalline common-, micro-, nanoscale and emulsified nanoscale sitosterol reduce equally the cholesterol pool in guinea pigs, but varying nanosystems result in different sterol concentrations in serosal jejunum.
abstract: Due to hypocholesterolemic effects, sitosterol is used in functional foods and nanoscale dispersions. To investigate the influence of dietary sitosterol on sterol concentrations in Dunkin Hartley guinea pigs, seven groups consisting of eight animals each were fed either a basal diet (BD), a high-cholesterol diet (HC) or a high-cholesterol diet supplemented with crystalline commonscale (CCS), microscale (CMS, low-dosed: CMLS), nanoscale (CNS) or emulsified nanoscale (ENS) sitosterol. When compared to HC group, all sitosterol formulations decreased liver cholesterol concentrations. No differences in cholesterol or sitosterol concentration were found in plasma and liver between CCS, CMS, CNS, and ENS groups. Apparent cholesterol digestibility decreased by increasing crystalline microscale sitosterol doses. Despite a lower sitosterol intake, ENS group had higher serosal sitosterol concentrations in jejunum than CNS group. To elucidate an impact of the sitosterol nanosystem on gut tissues further studies are necessary.
  
  
  BACKGROUND
  In this study, the use of sitosterols in a rat model led to contradicting conclusions regarding their ability to reduce cholesterol levels efficiently in guinea pigs, suggesting that more preclinical data is needed before this method could become applicable to human studies.
authors.affiliation: Friedrich Schiller University Jena, Institute of Nutrition, Department of Nutritional Physiology, 07743 Jena, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Jahreis
authors.forename: Steffen
authors.initials: S
authors.lastname: Wohlgemuth
authors.forename: Gregor
authors.initials: G
authors.lastname: Grünz
authors.forename: Lena
authors.initials: L
authors.lastname: Martin
authors.forename: Martin
authors.initials: M
authors.lastname: Knieling
authors.forename: Robert
authors.initials: R
authors.lastname: Engel
authors.forename: Michael
authors.initials: M
authors.lastname: Türk
authors.forename: Sylvia
authors.initials: S
authors.lastname: Keller
mesh_terms: D000818:Animals; D002784:Cholesterol / Q000097:blood / Q000378:metabolism*; D003460:Crystallization; D004032:Diet; D004655:Emulsions; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D007583:Jejunum / Q000378:metabolism*; D008099:Liver / Q000378:metabolism; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D051381:Rats; D012704:Serous Membrane / Q000378:metabolism*; D012855:Sitosterols / Q000097:blood / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D004655:Emulsions; D012855:Sitosterols; C025473:gamma-sitosterol; D002784:Cholesterol
keywords: ACAT; BD; CCS; CMLS; CMS; CNS; Cholesterol; DM; ENS; HC; LDL; NPC1L1; Nanosystem; Niemann-Pick C1 like 1 transporter; SD; Sitosterol; acyl-CoA cholesterol acyltransferase; basal diet; crystalline commonscale sitosterol; crystalline microscale low sitosterol; crystalline microscale sitosterol; crystalline nanoscale sitosterol; dry matter; emulsified nanoscale sitosterol; high cholesterol; low density lipoprotein; standard deviation