Supplementation of α-linolenic acid improves serum adiponectin levels and insulin sensitivity in patients with type 2 diabetes.
OBJECTIVE
ω-3 Polyunsaturated α-linolenic acid (ALA) supplementation has not been studied in the setting of adiponectin levels and insulin sensitivity (IS) improvements in patients with type 2 diabetes mellitus (T2DM) by hyperinsulinemic-euglycemic clamp (HEC). The aim of this study was to examine the influence of ω-3 ALA on IS and adiponectin.


METHODS
We conducted a randomized study in patients with T2DM and assessed IS using HEC. Twenty patients with T2DM were included and randomly assigned to receive 3 g/d of ALA or placebo for 60 d, in a double-blind design. The assessment of IS by HEC was performed at baseline and after 60 d in all patients; blood samples were taken for the measurement of serum lipids, glucose, insulin, adiponectin, and cytokines. The primary outcome variables were an increase of both glucose infusion rate (GIR) in steady state and glucose metabolization (M) by HEC. The secondary outcomes were an increase in adiponectin levels and a decrease in fasting plasma glucose, glycated hemoglobin, homeostasis model assessment-estimated insulin resistance (HOMA-IR) index, lipids and cytokines. The study was conducted at an academic medical center.


RESULTS
The ALA group improved IS corrected for fat-free mass (M/FFM; P = 0.04). Both groups showed increased adiponectin after 60 d (P = 0.01), however, the increase for the ALA group was greater (P = 0.04). In the ALA group, adiponectin was positively correlated with GIR (r = 0.76; P = 0.01) and M/FFM (r = 0.62; P = 0.06), and negatively correlated with HOMA-IR (r = -0.61; P = 0.03).


CONCLUSIONS
ω-3 ALA supplementation improved glucose homeostasis and was associated with an increase in adiponectin. Improvement in the overall metabolic profile with ω-3 ALA suggests a potential clinical utility for this agent and requires further investigation.
Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil. Electronic address: Dra.patricia.moreira@gmail.com.
Patricia M
PM
Gomes
Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil.
Wallace R
WR
Hollanda-Miranda
Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil.
Rebeca A
RA
Beraldo
Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil.
Ana V B
AV
Castro
Laboratory of Investigation on Metabolism and Diabetes, University of Campinas, Sao Paulo, Brazil.
Bruno
B
Geloneze
Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil.
Milton C
MC
Foss
Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil.
Maria C
MC
Foss-Freitas
D052242:Adiponectin / Q000097:blood*; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy* / Q000188:drug therapy; D004042:Dietary Fats, Unsaturated / Q000494:pharmacology / Q000627:therapeutic use; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D015309:Glucose Clamp Technique; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism; D006706:Homeostasis; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D017962:alpha-Linolenic Acid / Q000494:pharmacology / Q000627:therapeutic use*
D052242:Adiponectin; D001786:Blood Glucose; D004042:Dietary Fats, Unsaturated; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; D017962:alpha-Linolenic Acid; C499918:ADIPOQ protein, human
Adiponectin; Hyperinsulinemic-euglycemic clamp; Insulin resistance; Type 2 diabetes mellitus; α-Linolenic acid