title: Markers of absorption and synthesis of cholesterol in men with type 1 diabetes.
abstract: METHODS
  Serum cholestanol and plant sterol ratios to cholesterol, surrogate markers of cholesterol absorption, are assumed to be high in type 1 diabetes (T1D), and the ratios of cholesterol precursor sterols (markers of synthesis) are assumed to be low reflecting downregulated cholesterol synthesis. To this end, we measured serum sterols with gas-liquid-chromatography in 56 men with T1D and in 18 controls to evaluate cholesterol metabolism. Subjects were categorised into tertiles by the cholestanol to cholesterol ratio of controls indicating low to high absorption of cholesterol.
  
  
  RESULTS
  The ratios of the synthesis markers were negatively related to the absorption markers in controls, but less consistently in T1D. The absorption markers were positively related to each other, but interrelation of the synthesis markers was less consistent in T1D. In the low absorbers the absorption markers were higher in T1D than in controls (e.g. sitosterol ratio 173 +/- 9 in T1D vs 135 +/- 11 10(2) x mmol/mol of cholesterol in controls, p < 0.05). In the high absorbers, the absorption markers were similar in T1D and controls, but the synthesis markers were higher in T1D than in controls (e.g. lathosterol ratio 154 +/- 10 in T1D vs 120 +/- 5 10(2) x mmol/mol of cholesterol in controls, p < 0.05).
  
  
  CONCLUSIONS
  Absorption and synthesis of cholesterol are less closely related to each other in T1D than in controls, but the markers of cholesterol absorption are interrelated also in T1D. Absorption of cholesterol is higher in T1D than in controls within the range of low absorption, but similar in those with relatively high cholesterol absorption.
authors.affiliation: Department of Clinical Nutrition, University of Kuopio, Kuopio, Finland.
authors.forename: Helena
authors.initials: H
authors.lastname: Gylling
authors.forename: David E
authors.initials: DE
authors.lastname: Laaksonen
authors.forename: Mustafa
authors.initials: M
authors.lastname: Atalay
authors.forename: Maarit
authors.initials: M
authors.lastname: Hallikainen
authors.forename: Leo
authors.initials: L
authors.lastname: Niskanen
authors.forename: Tatu A
authors.initials: TA
authors.lastname: Miettinen
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002784:Cholesterol / Q000096:biosynthesis*; D002791:Cholesterol, Dietary / Q000378:metabolism*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000378:metabolism*; D006801:Humans; D007408:Intestinal Absorption; D008297:Male; D010840:Phytosterols / Q000097:blood; D012016:Reference Values
chemical_list: D015415:Biomarkers; D002791:Cholesterol, Dietary; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D010840:Phytosterols; D002784:Cholesterol