Endocrine Abstracts

Background and objective: Adipose tissue where energy homeostasis is regulated is now considered an endocrine organ. miRNAs may contribute to the regulation of energy balance and metabolic homeostasis, by controlling a wide range of metabolic pathways. miR-143 and miR-34a are the best studied among the miRNAs linked to adipose tissue regulation. Dietary intake, among many other environmental factors, is a key player that can induce epigenetic changes. The aim of the study was to investigate the association of the miR-143 and miR-34a expression in visceral and subcutaneous adipose tissues with habitual fat and oil intakes.

Materials and methods: Visceral and subcutaneous adipose tissues were obtained from 97 adults (41 non-obese, 18 obese, and 38 morbid obese), who underwent open abdominal surgery with minimal impact on dietary intake. Intake of hydrogenated and non-hydrogenated vegetable oils and butter were collected by using a valid and reliable food frequency questionnaire. The expressions of miR-143 and miR-34a in visceral and subcutaneous adipose tissues were measured by Real-Time PCR. Linear regression models were used to estimate association of dietary hydrogenated and non-hydrogenated vegetable oils and butter intake with miR-143 and miR-34a expression after adjustment for potential confounding variables.

Findings: Expression of miR-34a was more increased in morbid obese than obese subjects in both subcutaneous (13.3 vs 11.3, P<0.002) and visceral (13.4 vs 9.2, P<0.001) adipocytes. After adjustment for total energy intake, insulin, triglycerides, and age, visceral adipose tissue miR-143 expression was positively associated with total intakes of fats and oils (β=0.334, P=0.024) in the total population. The miR-143expression in visceral adiposity among morbid obese was negatively associated with non-hydrogenated vegetable oils (β=−0.317, P=0.036), and directly associated with butter (β=0.503, P=0.002) intake. The miR-34a expression among morbid obese participants was associated with total fats and oils (r=0.534, P<0.001) and non-hydrogenated oil (β=0.443, P=0.008) in visceral adipose tissue. Moreover, we found a significant association of miR-143 expression in subcutaneous adipose tissue with butter in both morbidly obese and non-obese participants.

Conclusions: A increase in miR-143 and miR-34a expression by total fats and oils, may explain the development of obesity through high-fat diet. A decrease in expression of miR-143 by non-hydrogenated oils would justify a lower adipogenic capacity and, would, therefore, contribute to the decrease of fat stores observed in adipose tissue with higher intake of fatty acids contains non-hydrogenated oils.