Study of Oral Anthocyanins on Insulin Resistance

Dietary strategies for alleviating the metabolic complications such as diabetes associated with obesity are actively being pursued as alternatives to pharmaceutical interventions The genus Vaccinium (e.g. blueberry, blaeberry, cranberry) has been used traditionally as a source of folk remedies for established diabetic symptoms, primarily as leaf or stem infusions or decoctions. Berries from this family such as blaeberry (BL) and blueberry (BB) are enriched in anthocyanins, polyphenolics recognized for their ability to provide and activate cellular antioxidant protection, inhibit inflammatory gene expression, and consequently protect against oxidant-induced and inflammatory cell damage and cytotoxicity. The association of obesity with adipose tissue stress, macrophage recruitment, and inflammatory gene expression suggests that eating edible berries from this genus might provide an effective alternative or supplementary intervention to attenuate obesity- associated inflammation and the associated insulin resistance. The aim of this study is to determine the effects of anthocyanin supplementation in the form of a concentrated blaeberry extract on insulin resistance and inflammation particularly in the adipose tissue following a three week supplementation period.

anthocyanin, blaeberries, bilberries, blueberries, mirtoselect, type 2 diabetes, insulin resistance, Adipose tissue, inflammation

30 obese male subjects (BMI > 30) with type 2 diabetes controlling their diabetes by diet alone or impaired glucose tolerance. Volunteers will be given a total daily dose of 1.4 grams of mirtoselect (a concentrated blaeberry extract) a day formulated in hard gelatin capsules (0.47 gram per capsule) administered thrice a day for 21 days. Mirtoselect provided by Indena S.p.A. (http://www.mirtoselect.info/)

30 obese male subjects (BMI > 30) with type 2 diabetes controlling their diabetes by diet alone or impaired glucose tolerance. Volunteers will be given a placebo consisting of lactose formulated in hard gelatin capsules administered thrice a day for 21 days.

Male subjects (BMI > 30) with type 2 diabetes controlling their diabetes by diet alone or impaired glucose tolerance. Volunteers will be given either a total daily dose of 1.4 grams of concentrated blaeberry extract (mirtoselect provided by Indena S.p.A. (http://www.mirtoselect.info/) in a hard gelatin capsules or control capsules containing lactose administered thrice a day for 21 days.

Inclusion Criteria: Obese male subjects (BMI > 30) Aged > 40 and < 70 years of age Type 2 diabetes; subjects controlling their diabetes by diet alone or with impaired glucose tolerance All the obese subjects will have a waist circumference over 40 inches All subjects must live the Aberdeenshire area of Scotland Exclusion Criteria: Medical exclusion criteria: Chronic illness, including: thromboembolic or coagulation disease, unregulated thyroid disease, kidney disease, hepatic disease, severe gastrointestinal disorders, pulmonary disease (e.g. chronic bronchitis, COPD), Alcohol or any other substance abuse, Eating disorders, Psychiatric disorders (including severe depression, lithium treatment, schizophrenia, severe behavioural disorders), Skin conditions on the abdomen, Allergy to skin dressings, Medication exclusion criteria: Oral steroids, Tricyclic antidepressants, neuroleptics, Anticoagulants, Digoxin and antiarrhythmics, Chronic use of antiinflammatories (e.g. high doses of aspirin, ibuprofen), Insulin, Sulphonylureas, Thiazolidinediones (glitazones), metformin

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