Fatty acid metabolism plays role in Type 2 diabetes etiology
MedWire News: Patients with Type 2 diabetes have an altered fatty acid pattern compared with individuals with normal glucose tolerance, research shows.
In particular, diabetics had diminished Δ5-desaturase activity that was inversely correlated with the homeostatic model assessment of insulin resistance (HOMA-IR), suggesting that "changes in fatty acid metabolism play a role in the etiology of Type 2 diabetes," say Geertruida van Woudenbergh (Wageningen University, The Netherlands) and colleagues.
Plasma or serum fatty acid profiles reflect endogenous conversion of ingested fatty acids by desaturation, elongation, or both.
The association between the proportion of individual fatty acids within fatty acid profiles and Type 2 diabetes and related markers have been investigated in several cross-sectional and longitudinal studies with varying results.
Proportions of trans-fatty acids (TFA) are of particular interest because they may increase inflammatory cytokines that could affect the process leading to Type 2 diabetes.
To investigate, the researchers reviewed data on 471 participants from the Dutch Cohort study on Diabetes and Atherosclerosis Maastricht (CoDAM).
Individual fatty acids in serum cholesteryl esters were determined and endogenous conversions by desaturases were estimated from product-to-precursor ratios. Proportions of fatty acids were compared among participants with normal glucose tolerance (n=279), impaired glucose metabolism (n=115), and newly diagnosed Type 2 diabetes (n=77).
The proportions of total monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and TFA did not differ significantly among the three groups, but proportions of several individual MUFA and PUFA did. The proportion of C18:1n7 was lower in participants with Type 2 diabetes (0.97%) than in those with normal glucose tolerance (1.07%) orimpaired glucose metabolism (1.05%).
The proportion of C20:3n6 was higher in those with Type 2 diabetes (0.86%) and impaired glucose metabolism (0.85%) than in those with normal glucose tolerance (0.80%).
Activity of Δ5-desaturase, that is, the ratio of C20:4n6 to C20:3n6, was lower in participants with Type 2 diabetes (7.4) than in those with normal glucose tolerance (8.4). HOMA-IR correlated positively with Δ9-desaturase activity and inversely with Δ5-desaturase activity.
"The major strength of this study was that information on serum cholesteryl fatty acids and diet was available," van Woudenbergh et al comment.
"Adjustment for energy, fiber, and alcohol hardly influenced mean proportions, which may suggest that the association between proportions of fatty acids and glucose tolerance status is not affected by these dietary factors."
The research is published in the journal Nutrition, Metabolism & Cardiovascular Diseases.
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By Andrew Czyzewski