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In NIDDM patients with hypertriglyceridemia, moderate amounts of fish oil induce a long-term significant reduction in plasma triglycerides, VLDL triglycerides, and NEFA and a significant enrichment in the erythrocyte phospholipid content of long-chain omega-3 fatty acids, without deteriorating blood glucose control. However, this amount of omega-3 fatty acids was unable to improve insulin sensitivity in this group of patients.

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Normolipidaemic insulin-dependent diabetic (IDDM) patients are characterized by an increase in the smaller VLDL particles, considered to be the most atherogenic. Since blood glucose control is one of the main regulators of lipid metabolism in diabetic patients, it could influence the shift in the distribution of VLDL subfractions towards smaller particles. To evaluate this possibility, VLDL subfractions, post-heparin lipoprotein lipase and hepatic lipase activities have been evaluated in male IDDM patients with either unsatisfactory blood glucose control (group 1, HbA1c > 8%, n = 18) or good blood glucose control (group 2, HbA1c < 8%, n = 16) and in 16 normoglycaemic individuals. The three groups were comparable for sex, age, body mass index, and plasma lipid levels. Three VLDL subfractions (large, Svedberg flotation unit (Sf) 175-400; intermediate, Sf 100-175; small, Sf 20-100) were separated by density gradient ultracentrifugation and analysed for cholesterol, triglyceride, and phospholipid levels. When compared to control subjects both groups of IDDM patients showed a clear shift in VLDL subfraction distribution with a significant increase in the proportion of small VLDL (group 1; 49 +/- 2%; p < 0.005; group 2: 51 +/- 3%, p < 0.01; control subjects 40 +/- 2%) (mean +/- SEM) in relation to total VLDL. By contrast, the absolute lipid concentration of small VLDL was higher only in group 1, compared to control subjects (35 +/- 4 vs 27 +/- 3 mg/dl, p = 0.05). Post-heparin hepatic lipase activity was significantly reduced in both IDDM groups (group 1: 254 +/- 19 mU/ml, p < 0.05; group 2: 202 +/- 19 mU/ml, p < 0.005; control subjects 317 +/- 31 mU/ml). In conclusion, normolipidaemic IDDM patients show an increase in the smallest VLDL, whatever their degree of blood glucose control. However, this abnormality may be clinically relevant only in patients with unsatisfactory blood glucose control, since absolute lipid concentration of these potentially atherogenic particles is only increased in this group.

Postprandial hyperglycemia is one of the earliest abnormalities of glucose homeostasis associated with type-2 diabetes and it is markedly exaggerated in diabetic patients with fasting hyperglycemia. An extensive body of data demonstrates a strong association between postprandial glucose levels and cardiovascular risk factors. Our article will focus on the concept of postprandial hyperglycemia, its physiopathology, its role on cardiovascular risk factors and the effects of new devices and a new faster insulin analog on postprandial hyperglycemia.

The study of the stability of saturated mono-, or polyunsaturated fatty acids, both esterified and not esterified, in plasma, circulating cells, and tissues is extremely important to validate the use of biological samples stored at low temperature in "biological banks", which are used for experimental, observational, dietary, or pharmacological studies. Since red blood cells are easily accessible cells, they are used as a marker of less-accessible tissues, especially in large-scale epidemiological studies. Data from the literature suggest that the addition of an antioxidant and the freezing of red blood cells do not cause any variation in the fatty acid composition for a period of 2-6 months up to 1 year. We evaluated the fatty acid concentration in red blood cells isolated from venous blood samples of one subject, preserved with butylated hydroxytoluene and N2 and stored at -80 degrees C for up to 2 years. Erythrocytes of venous samples of six subjects stored at -20 degrees C for 6 months without butylated hydroxytoluene and in the presence of air were used for comparison purposes. Our data demonstrate that a long storage time (2 years) does not significantly influence the erythrocyte fatty acid concentration when using very low temperatures (-80 degrees C) and antioxidants (butylated hydroxytoluene) in the presence of N2.

The study of the stability of saturated mono-, or polyunsaturated fatty acids, both esterified and not esterified, in plasma, circulating cells, and tissues is extremely important to validate the use of biological samples stored at low temperature in "biological banks", which are used for experimental, observational, dietary, or pharmacological studies. Since red blood cells are easily accessible cells, they are used as a marker of less-accessible tissues, especially in large-scale epidemiological studies. Data from the literature suggest that the addition of an antioxidant and the freezing of red blood cells do not cause any variation in the fatty acid composition for a period of 2-6 months up to 1 year. We evaluated the fatty acid concentration in red blood cells isolated from venous blood samples of one subject, preserved with butylated hydroxytoluene and N2 and stored at -80 degrees C for up to 2 years. Erythrocytes of venous samples of six subjects stored at -20 degrees C for 6 months without butylated hydroxytoluene and in the presence of air were used for comparison purposes. Our data demonstrate that a long storage time (2 years) does not significantly influence the erythrocyte fatty acid concentration when using very low temperatures (-80 degrees C) and antioxidants (butylated hydroxytoluene) in the presence of N2.