title: Visceral fat positively correlates with cholesterol synthesis in dyslipidaemic patients.
abstract: BACKGROUND
  Quantification of plasma noncholesterol sterols allows the study of cholesterol absorption and synthesis. A pattern of low cholesterol absorption and high synthesis has been demonstrated in patients with obesity and insulin resistance. To understand the relationship between cholesterol absorption/synthesis and visceral obesity, we investigated surrogate markers of cholesterol absorption (campesterol and sitosterol) and synthesis (lathosterol) in dyslipidaemic patients with different representation of abdominal fat, estimated by ultrasonographic measurement of visceral fat area (VFA).
  
  
  METHODS
  In 126 patients with primary hyperlipaemias, plasma sitosterol, campesterol and lathosterol were determined by gas chromatography coupled with mass spectrometry. Visceral and subcutaneous fats were evaluated by ultrasonography. The study population was divided into two groups on the basis of VFA median values, below/equal and above 154 cm(2) . RESULTS Patients with higher VFA had significantly higher lathosterol levels (median 109 vs. 76 × 10(2) μmol/mmol cholesterol P < 0·004), body mass index, waist circumference, blood pressure, triglycerides, insulin, homoeostatic model assessment (HOMA)-IR and lower high-density lipoprotein (HDL)-C. VFA was positively correlated with lathosterol (ρ = 0·35, P < 0·001) and negatively with HDL-C (ρ = -0·43, P < 0·001), campesterol (ρ = -0·23, P = 0.01) and sitosterol (ρ = -0·35, P < 0·001). VFA was an independent predictor of lathosterol values (β = 0·389, P < 0·0001, P of the model < 0·0001);age, systolic blood pressure, BMI, waist circumference, triglycerides, HDL-C and HOMA failed to enter the final equation.
  
  
  CONCLUSIONS
  In hyperlipidaemic patients, the amount of visceral fat correlates with cholesterol synthesis; the use of ultrasonographic detection of abdominal adiposity allows a better characterization of cholesterol pathway, potentially useful for a tailored therapeutic approach.
authors.affiliation: Internal Medicine, Angiology and Atherosclerosis, Department of Clinical and Experimental Medicine, University of Perugia, Italy. glupa@unipg.it
authors.forename: Graziana
authors.initials: G
authors.lastname: Lupattelli
authors.forename: Matteo
authors.initials: M
authors.lastname: Pirro
authors.forename: Massimo R
authors.initials: MR
authors.lastname: Mannarino
authors.forename: Donatella
authors.initials: D
authors.lastname: Siepi
authors.forename: Anna R
authors.initials: AR
authors.lastname: Roscini
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Schillaci
authors.forename: Elmo
authors.initials: E
authors.lastname: Mannarino
mesh_terms: D000328:Adult; D050218:Body Fat Distribution; D015992:Body Mass Index; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000097:blood; D002849:Chromatography, Gas / Q000379:methods; D050171:Dyslipidemias / Q000097:blood*; D005260:Female; D006801:Humans; D050152:Intra-Abdominal Fat / Q000000981:diagnostic imaging / Q000378:metabolism*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D008875:Middle Aged; D010840:Phytosterols / Q000097:blood*; D012855:Sitosterols / Q000097:blood*; D013223:Statistics as Topic; D014463:Ultrasonography / Q000379:methods; D055105:Waist Circumference
chemical_list: D010840:Phytosterols; D012855:Sitosterols; C021273:campesterol; C025473:gamma-sitosterol; C001521:lathosterol; D002784:Cholesterol