Abnormal capacity to induce cholesterol efflux and a new LpA-I pre-β particle in type 2 diabetic patients
Autor: | Rl Wikinski, Fd Brites, Gr Castro, Bernard Jacotot, C De Geitere, Jc. Fruchart, Elisabeth Cavallero, Nathalie Nicolaı̈ew, Maryvonne Rosseneu |
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Rok vydání: | 1999 |
Předmět: |
Adult
Male medicine.medical_specialty Clinical Biochemistry Population Biology Biochemistry chemistry.chemical_compound Liver Neoplasms Experimental Internal medicine Diabetes mellitus Tumor Cells Cultured medicine Animals Humans Protein Precursors Apolipoproteins C education Triglycerides Apolipoprotein C-III education.field_of_study Triglyceride Cholesterol Cholesterol HDL Biochemistry (medical) Reverse cholesterol transport Fasting General Medicine Middle Aged Postprandial Period medicine.disease Rats Endocrinology Postprandial Diabetes Mellitus Type 2 chemistry Cholesteryl ester lipids (amino acids peptides and proteins) Hemofiltration Lipoprotein(a) Lipoprotein |
Zdroj: | Clinica Chimica Acta. 279:1-14 |
ISSN: | 0009-8981 |
Popis: | In this study, we first characterized the lipoprotein components of serum samples obtained from a group of well-controlled diabetic patients and from healthy subjects in fasting and postprandial states. We then explored some aspects of reverse cholesterol transport in the same population. Patients showed high levels of fasting triglycerides, postprandial triglyceride responses and LpC-III levels (3.18+/-0.86 vs 2.17+/-0.54 mg/dl, P < 0.001). There were also positive correlations between LpC-III and fasting triglycerides (r = 0.82, P < 0.001), total triglyceride area (r = 0.75, P < 0.001) and incremental triglyceride area (r = 0.54, P < 0.001). HDL-C and apo A-I were significantly decreased in diabetic patients due to a selective reduction in LpA-I subfraction, whose antiatherogenic role is generally accepted (37.4+/-8.0 vs 49.2+/-12.5 mg/dl, P < 0.001). In addition, HDL from patients proved to be triglyceride enriched and cholesteryl ester depleted, alterations which were further amplified in the postprandial state. The molar ratio HDL-C/apo A-I + apo A-II, already defined as a predictor of apo A-I fractional catabolic rate, was significantly diminished in the patient group (15.1+/-2.2 vs 20.8+/-3.3, P < 0.001), thus suggesting an accelerated catabolism of apo A-I. For the first time, we describe here the presence of a small apo A-I-containing particle, isolated by two-dimensional electrophoresis and characterized by immunoblotting, only in samples from diabetic patients. This particle that we named pre-beta0, has an apparent molecular weight of 40 kDa. As regards the capacity of serum samples to promote cholesterol efflux from [3H]cholesterol-labeled Fu5AH rat hepatoma cells, patient samples were found to induce significantly lower cholesterol efflux than controls only in the postprandial state (21.2+/-3.3 vs 23.8+/-1.8%, P = 0.012). The presence of pre-beta0 in samples from diabetic patients might therefore be associated to an altered capacity of these serum samples to promote cellular cholesterol efflux. Overall, these abnormalities may contribute to a delay in the reverse cholesterol transport pathway in type 2 diabetic patients. |
Databáze: | OpenAIRE |
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