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Peltola P, Pihlajamäki J, Koutnikova H, Ruotsalainen E, Salmenniemi U, Vauhkonen I, Kainulainen S, Gylling H, Miettinen TA, Auwerx J, Laakso M. Visceral obesity is associated with high levels of serum squalene. Obesity (Silver Spring) 2006; 14:1155-63. [PMID: 16899796 DOI: 10.1038/oby.2006.132] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To investigate the impact of visceral obesity on cholesterol metabolism in normoglycemic offspring of patients with type 2 diabetes. RESEARCH METHODS AND PROCEDURES The proportion of intra-abdominal fat (IAF) was measured by abdominal computer tomography, and serum cholesterol synthesis and absorption markers were determined by gas-liquid chromatography in 109 normoglycemic offspring of patients with type 2 diabetes. Insulin action was measured with the hyperinsulinemic euglycemic clamp. The gene encoding squalene synthase (farnesyl-diphosphate farnesyltransferase 1) was screened with the single-strand conformation polymorphism analysis and direct sequencing. RESULTS Cholesterol synthesis markers correlated positively with IAF (r = 0.213 to 0.309, p < or = 0.027) and negatively with the rates of insulin-stimulated whole-body glucose uptake (r = -0.372 to -0.248, p < or = 0.010). However, serum squalene, the first measured precursor of cholesterol synthesis, showed a positive correlation with IAF (r = 0.309, p = 0.001) without any association with subcutaneous fat or insulin sensitivity. Variation in the farnesyl-diphosphate farnesyltransferase 1 gene did not explain elevated serum squalene levels in viscerally obese subjects. From the cholesterol absorption markers, cholestanol was associated negatively with IAF and positively with whole-body glucose uptake (p < 0.05). DISCUSSION High serum squalene levels are associated with visceral obesity but not with subcutaneous obesity. Whether this finding is causally connected to visceral obesity remains to be established.
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Miettinen TA, Gylling H. Plant stanol and sterol esters in prevention of cardiovascular diseases: a review. Int J Clin Pharmacol Ther 2006; 44:247-50. [PMID: 16800096 DOI: 10.5414/cpp44247] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Plant sterol and stanol esters have been introduced as an additional dietary means to lower serum total and LDL cholesterol concentration. In short-term studies they lower LDL cholesterol by 10%, and according to a meta-analysis by Malcolm Law the incidence of coronary heart disease is considered to be reduced by over 20% in long-term use of these products. Plant stanol and sterol esters are not identical sterols; they have different metabolic effects and their long-term efficacy seems to be different. The present review deals with the differences of the sterols and discusses what is known of their role in preventing the cardiovascular diseases.
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Gylling H, Miettinen TA. Cholesterol absorption: influence of body weight and the role of plant sterols. Curr Atheroscler Rep 2006; 7:466-71. [PMID: 16256005 DOI: 10.1007/s11883-005-0064-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Cholesterol absorption and synthesis are inter-regulated, so if one changes then the other changes in the opposite direction. The regulation and detailed mechanism of cholesterol absorption have been intensely investigated. Inhibition of cholesterol absorption has become an additional factor for cholesterol lowering. Agents inhibiting cholesterol absorption, mainly plant stanols and sterols or ezetimibe, usually lower low-density lipoprotein cholesterol in monotherapy by less than 20%, indicating that these inhibitors can normalize cholesterol levels only in patients with a modest baseline hypercholesterolemia. Body weight, especially obesity with and without diabetes, and dietary plant sterols alter cholesterol absorption differently. This article briefly reviews some special questions of cholesterol absorption under these conditions.
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Hassinen M, Komulainen P, Lakka TA, Väisänen SB, Haapala I, Gylling H, Alen M, Schmidt-Trucksäss A, Nissinen A, Rauramaa R. Metabolic syndrome and the progression of carotid intima-media thickness in elderly women. ACTA ACUST UNITED AC 2006; 166:444-9. [PMID: 16505265 DOI: 10.1001/archinte.166.4.444] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Although the metabolic syndrome can predict cardiovascular events in middle-aged individuals, data on its association with the progression of subclinical atherosclerosis, particularly in elderly women, are limited. We investigated the association of the metabolic syndrome with the progression of carotid intima-media thickness (IMT) in elderly women. METHODS We performed a 12-year follow-up study in a population-based sample of 101 women (age range at baseline, 60-70 years). All study variables were measured at baseline and 12 years later. We used the National Cholesterol Education Program definition for metabolic syndrome (> or =3 of 5 risk factors) and quantified carotid IMT noninvasively by ultrasonography. RESULTS The prevalence of metabolic syndrome increased from 13% at baseline to 46% after 12 years of follow-up (P<.001). The mean +/- SD IMT increased by 21% (from 1.05 +/- 0.31 mm to 1.27 +/- 0.38 mm) during 12 years (P<.001). Among the individuals without metabolic syndrome at baseline, the increase in carotid IMT was greater in 34 women who developed metabolic syndrome during 12 years (0.31 +/- 0.37 mm) than in 54 women who did not (0.16 +/- 0.25 mm) after adjustment for age, prevalent cardiovascular diseases, physical activity, smoking, alcohol intake, serum low-density lipoprotein cholesterol level, use of cholesterol-lowering medication, carotid IMT, and National Cholesterol Education Program metabolic risk score at baseline (P = .04 for difference). CONCLUSION Incident metabolic syndrome is associated with accelerated progression of carotid IMT in elderly women.
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Miettinen TA, Railo M, Lepäntalo M, Gylling H. Reply. J Am Coll Cardiol 2006. [DOI: 10.1016/j.jacc.2006.01.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Hassinen M, Lakka TA, Komulainen P, Gylling H, Nissinen A, Rauramaa R. C-reactive protein and metabolic syndrome in elderly women: a 12-year follow-up study. Diabetes Care 2006; 29:931-2. [PMID: 16567842 DOI: 10.2337/diacare.29.04.06.dc05-2508] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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Gylling H, Rajaratnam RA, Vartiainen E, Puska P, Miettinen TA. Changes in serum level and metabolism of cholesterol with plant stanol esters in postmenopausal women with and without coronary artery disease. Menopause 2006; 13:286-93. [PMID: 16645542 DOI: 10.1097/01.gme.0000174095.49029.56] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Especially in women, serum cholesterol lowering with cholesterol malabsorption using plant sterol ester margarine has revealed controversial results. Accordingly, in this retrospective study, we evaluated whether plant stanol (3 g/d) ester margarine consumption for 6 and 12 weeks lowers serum cholesterol levels in mildly hypercholesterolemic women without (n = 38) and with (n = 22) coronary heart disease. DESIGN The study population was selected from two of our earlier studies correspondingly matched for age, body mass index, and serum cholesterol and triglyceride levels. In addition, the long-term effect (12 months) of plant stanol ester with a dose reduction after 6 months (from 3-2 g stanol/d) was studied in the noncoronary group. RESULTS At baseline, the coronary and noncoronary groups had similar serum lathosterol (synthesis marker) and campesterol and sitosterol (absorption markers) ratios to cholesterol, but high-density lipoprotein cholesterol was lower and serum squalene and desmosterol ratios to cholesterol were significantly higher in the coronary versus noncoronary groups. Short-term plant stanol ester consumption reduced serum cholesterol by 8.7% (P < 0.001) in the coronary group from the control margarine period, and in the noncoronary group by 11% from the control group (P < 0.001). The cholesterol-lowering effect sustained unchanged in the noncoronary subjects during one year consumption despite reduction of the plant stanol intake from 3 g/d to 2 g/d. CONCLUSION Plant stanol ester margarine consumption effectively reduced serum cholesterol in postmenopausal women with and without coronary artery disease in short-term and for at least 1 year in the noncoronary group, suggesting that stanol ester margarine might be used in the long-term for cholesterol lowering in women.
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Gylling H, Miettinen TA. Drug-induced effects on cholesterol catabolism and bile acids. CURRENT OPINION IN INVESTIGATIONAL DRUGS (LONDON, ENGLAND : 2000) 2006; 7:214-8. [PMID: 16555681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Serum cholesterol level is a reflection of whole-body cholesterol metabolism, which is tightly regulated so that cholesterol absorption and synthesis are interrelated. The actions of serum cholesterol-lowering drugs are based primarily on influencing cholesterol synthesis (statins), cholesterol absorption (ezetimibe) or bile acid synthesis (resins). A great deal of research has been targeted at developing drugs that inhibit the metabolism of cholesterol in enterocytes, such as microsomal transfer protein inhibitors and acyl-cholesterol acyl transferase inhibitors, but there are little published data regarding their effect on whole-body cholesterol metabolism in humans. Cholesterol is catabolized and excreted as neutral sterols of cholesterol into feces, and by conversion to bile acids. This review examines lipid-lowering drugs and their effect on cholesterol metabolic pathways.
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Hedman M, Miettinen TA, Gylling H, Ketomäki A, Antikainen M. Serum noncholesterol sterols in children with heterozygous familial hypercholesterolemia undergoing pravastatin therapy. J Pediatr 2006; 148:241-6. [PMID: 16492436 DOI: 10.1016/j.jpeds.2005.08.068] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2005] [Revised: 06/29/2005] [Accepted: 08/24/2005] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To assess causes for insufficient cholesterol-lowering response to pravastatin and plant stanol esters in children with heterozygous familial hypercholesterolemia (HeFH). STUDY DESIGN Nine of 16 children with HeFH who had not reached normocholesterolemia (< or =194 mg/dL [< or =5 mmol/L]) by 1 year after treatment (40 mg pravastatin and plant stanol ester) were called nonresponders. The 7 remaining children were responders. Serum noncholesterol sterol ratios (10(2) x mmol/mol of cholesterol), surrogate estimates of cholesterol absorption (cholestanol, campesterol, sitosterol) and synthesis (desmosterol and lathosterol), were studied at study baseline (on plant stanol esters) and during combination therapy with pravastatin and plant stanol esters. RESULTS Pravastatin decreased the serum levels of cholesterol and cholesterol synthesis markers, and increased the ratios of cholesterol absorption markers. Compared with the responders, the nonresponders had higher study baseline (on plant stanol esters) serum cholesterol concentrations (299 +/- 39 vs 251 +/- 35 mg/dL [7.7 +/- 1.0 vs 6.5 +/- 0.9 mmol/L]; P <.001) and higher respective ratios of campesterol (371 +/- 99 vs 277 +/- 67 10(2) x mmol/mol of cholesterol; P = .049) and sitosterol (176 +/- 37 vs 126 +/- 24 10(2) x mmol/mol of cholesterol; P = .008). The higher the ratio of cholestanol at study baseline, the smaller the 1-year percent reduction in cholesterol (r = .556; P = .025). CONCLUSIONS Pravastatin treatment increases the markers of cholesterol absorption and decreases those of cholesterol synthesis in HeFH during simultaneous inhibition of cholesterol absorption. Combined inhibition of cholesterol absorption and synthesis may not normalize serum lipids in those patients with the highest cholesterol levels, especially if signs of enhanced cholesterol absorption are detectable.
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Miettinen TA, Klett EL, Gylling H, Isoniemi H, Patel SB. Liver transplantation in a patient with sitosterolemia and cirrhosis. Gastroenterology 2006; 130:542-7. [PMID: 16472606 PMCID: PMC1391914 DOI: 10.1053/j.gastro.2005.10.022] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2005] [Accepted: 10/12/2005] [Indexed: 12/18/2022]
Abstract
Sitosterolemia (MIM 210250) is a rare genetic disorder caused by disruption of the normal mechanisms that regulate dietary cholesterol absorption and prevent the accumulation of noncholesterol sterols. As a result of this defect, affected individuals accumulate high concentrations of plant sterols in plasma and tissues. They present clinically with tendon or tuberoeruptive xanthomas, premature coronary artery disease, and/or hemolytic anemia. Two genes, ABCG5 and ABCG8, compose the STSL locus, and complete mutation in either, but not both, results in disease. The expression of these genes is confined to the intestine and liver. They are thought to function as sterol efflux pumps. It is not clear which organ, liver or intestine, is of greater importance in maintaining sterol balance with respect to noncholesterol sterols. We report here a case of a patient who presented with "chronic active liver disease" and was found to have sitosterolemia by chance and subsequently underwent orthotopic liver transplantation. Following transplantation, the grossly elevated pretransplantation serum plant sterol levels decreased to values only slightly higher than those of the patient's heterozygous father. This case highlights 2 important features: (1) The liver functions as the predominant organ for maintaining noncholesterol sterol balance (because the intestinal defect was not altered), and (2) a new clinical feature of undiagnosed sitosterolemia may be "idiopathic" liver disease. Because the diagnosis of sitosterolemia is based on specialized plasma analyses, we would propose that some consideration to this diagnosis should be given in appropriate cases.
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Siirtola A, Ketomäki A, Miettinen TA, Gylling H, Lehtimäki T, Holmberg C, Salo MK, Antikainen M. Cholesterol Absorption and Synthesis in Pediatric Kidney, Liver, and Heart Transplant Recipients. Transplantation 2006; 81:327-34. [PMID: 16477216 DOI: 10.1097/01.tp.0000189173.46727.18] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Hypercholesterolemia after organ transplantation is common. Previously, we observed higher serum total cholesterol (TC) concentrations in our pediatric kidney than liver or heart transplant recipients. To find an explanation to the observed difference, our kidney recipients' cholesterol synthesis and absorption efficiency was compared to those of liver and heart recipients. METHODS Serum noncholesterol sterol ratios (10 x mmol to the mol of TC, surrogate estimates of hepatic cholesterol synthesis and intestinal absorption) were studied in 50 pediatric kidney, 25 liver and 12 heart transplant recipients without diabetes or cholestasis, and in 29 controls. RESULTS The kidney recipients had lower Delta-cholesterol (P=0.031), similar lathosterol and higher desmosterol ratios (markers of cholesterol synthesis) (P=0.020), and similar campesterol and sitosterol ratios (markers of cholesterol absorption) when compared to the controls. The liver recipients had lower campesterol ratios than the kidney recipients and controls (P=0.002). Glomerular filtration rates were not associated with the ratios of noncholesterol sterols. Multivariate analysis showed markers of cholesterol synthesis to be lower and absorption to be higher in the kidney than the liver or the heart transplant recipients. Weight-adjusted dosages of immunosuppressive agents were associated with some ratios of noncholesterol sterols and cholestanol though these varied between the transplant recipient groups. CONCLUSIONS Serum TC concentration in kidney recipients was not significantly associated with absorption efficiency or synthesis of cholesterol, though kidney transplantation was associated with low synthesis and high absorption efficiency of cholesterol. Immunosuppressive therapy with cyclosporine and methylprednisolone may modulate absorption efficiency and synthesis of cholesterol.
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Berthold I, Ko Y, Stier S, Giannakidou E, Gylling H, Plat J, Berthold HK, Krone W. Effects of ezetimibe on LDL receptor- and HMG-CoA reductase-gene expression, on LDL receptor protein expression and on HMG-CoA reductase activity in mononuclear blood cells of healthy men – A randomized trial. DIABETOL STOFFWECHS 2006. [DOI: 10.1055/s-2006-943778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Agren JJ, Hallikainen M, Vidgren H, Miettinen TA, Gylling H. Postprandial lipemic response and lipoprotein composition in subjects with low or high cholesterol absorption efficiency. Clin Chim Acta 2005; 366:309-15. [PMID: 16364276 DOI: 10.1016/j.cca.2005.11.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2005] [Revised: 11/09/2005] [Accepted: 11/09/2005] [Indexed: 11/22/2022]
Abstract
BACKGROUND The purpose of this study was to investigate the effect of differences in cholesterol absorption efficiency on the postprandial lipemia and lipoprotein composition. METHODS Fifteen healthy subjects were divided into low and high cholesterol absorbers on the basis of serum cholestanol to cholesterol ratio. A high-performance liquid chromatographic method with evaporative light scattering detection was developed for quantitation of free and esterified cholesterol, triglycerides and major phospholipids from the same lipid extract in two runs utilizing the same internal standard. RESULTS The free cholesterol to phosphatidylcholine ratio of chylomicrons was higher in the high cholesterol absorption group. The total increase of cholesterol in combined chylomicron and very low density lipoprotein (VLDL) fraction was also higher in this group. Chylomicron free cholesterol and cholesterol ester responses correlated with fasting low density lipoprotein (LDL) cholesterol. VLDL and VLDL1 triglyceride responses correlated inversely with fasting insulin and homeostasis model assessment of insulin resistance. CONCLUSIONS High cholesterol absorption efficiency was seen in chylomicrons as higher cholesterol to phosphatidylcholine ratio during the postprandial peak. Chylomicron cholesterol response was linked to fasting LDL cholesterol and low VLDL triglyceride response to fasting insulin.
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165
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Miettinen TA, Gylling H. Effect of statins on noncholesterol sterol levels: implications for use of plant stanols and sterols. Am J Cardiol 2005; 96:40D-46D. [PMID: 15992515 DOI: 10.1016/j.amjcard.2005.03.019] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Normal serum contains small amounts of noncholesterol sterols, including those reflecting cholesterol absorption and those that are markers of cholesterol synthesis. Absorption marker sterols include serum plant sterols, whereas cholesterol precursor sterols correlate with whole-body synthesis of cholesterol. Thus, serum noncholesterol sterols, and especially their ratios to cholesterol, can be used to evaluate the major features of cholesterol metabolism (ie, synthesis and absorption). Statin treatment reduces serum cholesterol precursors but increases serum plant sterols severalfold, especially in subjects with high-absorption marker sterol levels indicative of efficient cholesterol and sterol absorption in general. Statin therapy is most effective in subjects with high serum cholesterol precursor levels. In subjects with high-absorption sterol markers, dietary cholesterol absorption inhibition (eg, with plant stanol and sterol ester margarine) needs to be combined with a statin to achieve effective serum cholesterol reduction. However, whereas dietary plant stanol esters reduce statin-induced elevations of serum plant sterol levels, serum plant sterol levels remain elevated during dietary plant sterol ester consumption. The clinical implication of high serum plant sterol levels is under active investigation.
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Miettinen TA, Railo M, Lepäntalo M, Gylling H. Plant Sterols in Serum and in Atherosclerotic Plaques of Patients Undergoing Carotid Endarterectomy. J Am Coll Cardiol 2005; 45:1794-801. [PMID: 15936608 DOI: 10.1016/j.jacc.2005.02.063] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2004] [Revised: 01/28/2005] [Accepted: 02/08/2005] [Indexed: 10/25/2022]
Abstract
OBJECTIVES The purpose of this research was to determine whether serum plant sterol levels are associated with those in atheromatous plaque. BACKGROUND Cholesterol of low-density lipoprotein (LDL) particles contributes to atheromatous plaque formation; LDL also contains most serum non-cholesterol sterols, including plant sterols. The role of plant sterols in atheromatous plaque formation is open. METHODS Free, ester, and total cholesterol and the respective non-cholesterol sterols were measured by gas-liquid chromatography in serum and arterial tissue of 25 consecutive patients undergoing carotid endarterectomy. The population was ranked to triads according to tissue cholesterol concentration. RESULTS Cholesterol concentration increased markedly in tissues but not in serum with triads. The ester percentage was lower in the third than in the first triad (47% vs. 56%; p < 0.01) and lower than in serum triads (70%; p < 0.001). Ratios to cholesterol of non-cholesterol sterols decreased in increasing tissue triads, but were unchanged in serum. A major new observation was that the higher the ratio to cholesterol of the surrogate absorption sterols (cholestanol, campesterol, sitosterol, and avenasterol) in serum, the higher was their ratio also in the carotid artery wall (e.g., r = 0.683 for campesterol). Despite undetectable differences in serum and tissue cholesterol concentrations off and on statins, an additional important novel finding was that statin treatment was associated with increased ratios of the absorption sterols in serum and also in the arterial plaque. CONCLUSIONS The higher the absorption of cholesterol, the higher are the plant sterol contents in serum resulting also in their higher contents in atherosclerotic plaque. However, the role of dietary plant sterols in the development of atherosclerotic plaque is not known.
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Ketomäki A, Gylling H, Miettinen TA. Non-cholesterol sterols in serum, lipoproteins, and red cells in statin-treated FH subjects off and on plant stanol and sterol ester spreads. Clin Chim Acta 2005; 353:75-86. [PMID: 15698593 DOI: 10.1016/j.cccn.2004.10.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2004] [Revised: 10/04/2004] [Accepted: 10/08/2004] [Indexed: 11/25/2022]
Abstract
BACKGROUND Serum plant sterol levels are increased by consumption of statins and dietary plant sterols, and decreased by dietary plant stanols, but little is known about combination therapy of statin and plant sterols. METHODS We measured plant sterols in serum, lipoproteins, and red cells in subjects with familial hypercholesterolemia (FH) (n=18) treated with variable doses of statins off and on plant stanol (STA) and sterol ester (STE) spreads. RESULTS STA and STE spreads lowered LDL cholesterol approximately 15%. Plant sterols were decreased in serum, lipoproteins, and red cells by approximately 25% with STA and increased from 37% to 80% with STE, especially with high statin doses. The changes in serum were related to those in red cells. The baseline levels of serum plant sterols were negatively (r-range -0.639 to -0.935) and positively (r-range 0.526 to 0.598) correlated with the respective changes evoked by the STA and STE spreads. CONCLUSIONS STE reduces LDL cholesterol, but increases serum, lipoprotein, and red cell plant sterol levels in statin-treated FH subjects, while all the respective values are decreased with STA. Recent predictions that elevated serum plant sterols pose an increased coronary risk suggest that increases of serum plant sterol levels should be avoided, especially in atherosclerosis-prone individuals, such as subjects with FH.
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Gylling H, Hallikainen M, Pihlajamäki J, Agren J, Laakso M, Rajaratnam RA, Rauramaa R, Miettinen TA. Polymorphisms in the ABCG5 and ABCG8 genes associate with cholesterol absorption and insulin sensitivity. J Lipid Res 2004; 45:1660-5. [PMID: 15175352 DOI: 10.1194/jlr.m300522-jlr200] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The roles of polymorphisms of the sitosterolemia genes ABCG5 and ABCG8 in the regulation of cholesterol metabolism and insulin sensitivity were studied in mildly hypercholesterolemic noncoronary subjects (n = 263, 144 men and 119 women) divided into tertiles by baseline serum cholestanol-to-cholesterol ratio (< or = 118.3 and > or = 147.7 10(2) x mmol/mol cholesterol), a surrogate marker of cholesterol absorption efficiency. The lowest cholestanol tertile was associated with high body mass index (BMI), plasma glucose, serum insulin and triglycerides, and cholesterol synthesis markers (cholestenol, desmosterol, lathosterol) and low HDL cholesterol and cholesterol absorption markers (campesterol, sitosterol) (P < 0.01 for all). The 19H allele of the ABCG8 gene accumulated in the lowest cholestanol tertile (P < 0.001) and was associated with low total and LDL cholesterol and absorption markers and with high synthesis markers (P < 0.05 for all). The 604E allele of the ABCG5 gene in men was associated with high BMI, plasma insulin, low serum sitosterol, and high serum cholestenol levels (P < 0.05 for all). In a subgroup of 71 men, the 604E allele was associated with insulin resistance measured with the hyperinsulinemic euglycemic clamp. In conclusion, low cholesterol absorption efficiency was associated with characteristics of the metabolic syndrome. Low serum cholesterol and cholesterol absorption were linked to the D19H polymorphism of the ABCG8 gene, and characteristics of the insulin resistance syndrome in men were linked with the Q604E polymorphism of the ABCG5 gene.
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Gylling H. Cholesterol metabolism and its implications for therapeutic interventions in patients with hypercholesterolaemia. Int J Clin Pract 2004; 58:859-66. [PMID: 15529520 DOI: 10.1111/j.1742-1241.2004.00351.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Cardiovascular diseases are the principal causes of mortality in middle-aged people and in older people. Coronary heart disease (CHD) is the most common of the cardiovascular diseases; high serum levels of cholesterol are associated with atherosclerosis and an increased risk of CHD. Cholesterol homeostasis is achieved by means of a fine balance between cholesterol intake, absorption/excretion and synthesis. All of these processes are tightly linked and a change in one of them can significantly influence the others. Results from both experimental studies and clinical trials have shown that inhibition of cholesterol synthesis with a statin increases absorption and that conversely, inhibition of cholesterol absorption increases synthesis. The tight linkage of cholesterol absorption and synthesis in maintaining cholesterol homeostasis suggests that treatment with an agent that influences only one of these two processes is likely to have distinct limits with respect to its effects on cholesterol levels. Better understanding of cholesterol homeostasis, particularly the close interrelationship between cholesterol synthesis and absorption, may result in the design of rational integrated treatment regimens that employ multiple agents with complementary actions that attack multiple mechanisms to lower cholesterol.
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Abstract
Little information is available on cholesterol absorption and synthesis in human type 1 diabetes. We studied these variables using serum cholesterol precursor sterol ratios to cholesterol as surrogate markers of cholesterol synthesis and those of cholestanol and plant sterols to reflect cholesterol absorption in seven type 1 diabetic subjects and in five age- and body weight-matched control subjects. Total and lipoprotein cholesterol levels were similar, but triglycerides in intermediate-density lipoprotein (IDL) and LDL were higher in type 1 diabetic than in control subjects. Most of the marker sterols were transported by LDL and HDL in both groups. The percentage of esterified cholesterol was lower in triglyceride-rich lipoproteins in diabetic patients than in control subjects. The ratios of the absorption marker sterols in serum were higher, and those of the synthesis markers were lower in type 1 diabetic than in control subjects. The increased cholestanol ratios were seen in all lipoproteins, and those of free and total plant sterols were mainly in LDL, whereas the decreased free and total synthesis markers were mainly in all lipoproteins. In conclusion, high absorption and low synthesis marker sterols seem to characterize human type 1 diabetes. These findings could be related to low expression of ABC G/5 G/8 genes, resulting in high absorption of cholesterol and sterols in general and low synthesis of cholesterol compared with type 2 diabetes.
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Nissinen MJ, Gylling H, Järvinen HJ, Miettinen TA. Ileal pouch-anal anastomosis, conventional ileostomy and ileorectal anastomosis modify cholesterol metabolism. Dig Dis Sci 2004; 49:1444-53. [PMID: 15481317 DOI: 10.1023/b:ddas.0000042244.56689.72] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Proctocolectomy modifies the enterohepatic circulation and activity of bacterial enzymes depending on the structure of the stoma and function of the terminal ileum. We evaluated in our comparative study effects of different colectomy constructions on cholesterol metabolism. Levels of lipoprotein cholesterol and triglycerides, noncholesterol sterols, and squalene in serum, fecal fat, and bile acids, cholesterol absorption efficiency, and cholesterol metabolism by sterol balance technique were analyzed in human subjects with ileal pouch-anal anastomosis (n = 34), conventional ileostomy (n = 8), ileorectostomy (n = 6), and controls (n = 29). Malabsorption of bile acids, but not of fat, and low serum levels of total and low-density lipoprotein cholesterol, but high levels of high-density lipoprotein cholesterol and increased cholesterol synthesis were evident in the colectomy groups. In contrast to the ileorectostomy group, expressing high absorption and biliary secretion of cholesterol, a low cholesterol absorption percentage accompanied by elevated serum proportions of cholesterol precursor sterols and phytosterols characterized the ileal pouch-anal anastomosis and conventional ileostomy groups. After colectomy, fecal excretion of secondary bile acids was low, whereas relative proportions of identifiable bile acids remained the same in each study group. Low serum levels of total and low-density lipoprotein cholesterol of colectomized subjects may decrease the risk of premature atherosclerosis. The favorable serum lipid profile was due to enhanced fecal loss of cholesterol as bile acids despite abnormally high cholesterol synthesis. Ileal dysfunction probably diminished cholesterol absorption in subjects with ileal pouch-anal anastomosis and conventional ileostomy, with no explanation for those with ileorectostomy with no clinical gastrointestinal dysfunction. Relative synthesis of identifiable primary bile acids remained unchanged postoperatively, but formation of secondary bile acids was weak due to scarce bacterial flora.
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Ketomäki A, Gylling H, Miettinen TA. Removal of intravenous Intralipid in patients with familial hypercholesterolemia during inhibition of cholesterol absorption and synthesis. Clin Chim Acta 2004; 344:83-93. [PMID: 15149875 DOI: 10.1016/j.cccn.2004.02.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2004] [Revised: 02/09/2004] [Accepted: 02/11/2004] [Indexed: 11/17/2022]
Abstract
BACKGROUND While plant stanols are known to upregulate low density lipoprotein (LDL) receptors, we studied the effects of plant stanol (STA) and sterol (STE) ester spreads on triglyceride-rich lipoprotein (TRL) removal in statin-treated patients with familial hypercholesterolemia (FH) using intravenous Intralipid-squalene fat tolerance test. METHODS Five patients consumed STA and STE in a randomized, crossover study for 4 weeks. TRL removal was studied at baseline and at the end of both periods. Serum, chylomicron (CM), and very low density lipoprotein lipids, squalene, and plant sterols were measured. RESULTS LDL cholesterol was decreased by both spreads (15-16%, p<0.05). Plant sterol concentrations were doubled in serum and CM by STE vs. STA. After the injection of Intralipid, CM squalene and sitosterol, but not triglycerides (TG), reached higher peak levels (and area under the incremental curve (AUIC) of squalene) by both spreads than at baseline. Despite different plant sterol concentrations by STE vs. STA, the incremental curves for plant sterols were similar by the spreads. CONCLUSIONS Despite the retarded removal of TRL lipids by STA and STE in the statin-treated subjects with FH, improvement of the fasting lipid profile was suggested important in consideration of combination of cholesterol absorption inhibitor with statins even in FH.
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Martikainen T, Pirinen E, Alhava E, Poikolainen E, Pääkkönen M, Uusitupa M, Gylling H. Long-term Results, Late Complications and Quality of Life in a Series of Adjustable Gastric Banding. Obes Surg 2004; 14:648-54. [PMID: 15186633 DOI: 10.1381/096089204323093435] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Adjustable gastric banding is currently the most common bariatric operation. This study is a retrospective analysis of the Finnish experience with this procedure over the last 10 years. METHODS Between March 1993 and June 1999, 123 patients underwent either open (36) or laparoscopic (87) surgery for morbid obesity by the application of an adjustable gastric band. Data on preoperative clinical characteristics and postoperative outcome and weight-loss patterns up to 9 years (mean 55 months) are presented and also evaluated by the Bariatric Analysis and Reporting Outcome System (BAROS). Sex ratio was 31% males / 69% females, mean age 44 years and mean +/- SD preoperative BMI 49 +/- 8 kg/m(2) (range 33.6-85.1). RESULTS During the evaluation period (March 1993 December 2002), 54% of patients experienced postoperative complications requiring hospital treatment >or= 7 days, and 52% underwent a reoperation. 33% of bands were removed. The most important late complications were esophagitis (30%), obstruction due to slippage / pouch dilatation (21%), incisional hernia (9%) and band erosion (9%). Mean excess weight loss at 1 and 2 year follow-up was 36% and 38%, which later stabilized to 30%. During the evaluation period, there were 10 deaths, 2 of which were 30-day deaths, and the remainder were not associated with the band. According to BAROS, the outcome was regarded as "very good" in 3%, "good" in 7%, "fair" in 40% and "failure" in 50%. CONCLUSION Our long-term data found that weight reduction is acceptable,but the incidence of late complications and reoperations was high.
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Gylling H, Hallikainen M, Pihlajamäki J, Ågren J, Laakso M, Miettinen T. W14.361 Polymorphism in the ABCG5 and ABCG8 genes and cholesterol and glucose metabolism in mild hypercholesterolemia. ATHEROSCLEROSIS SUPP 2004. [DOI: 10.1016/s1567-5688(04)90360-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Ketomäki A, Gylling H, Miettinen T. W12.297 Clearance of postprandial lipids in statin-treated FH patients off and on stanol and sterol ester spread consumption. ATHEROSCLEROSIS SUPP 2004. [DOI: 10.1016/s1567-5688(04)90296-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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