Obesity, Inflammation and Aging: Effects of Physical Exercise and Omega-3 Fatty Acids.

Dysfunction of adipose tissue in obesity, inflammation and aging: mechanisms and effects of physical exercise and omega-3 fatty acids.

Obesity is associated with the development of metabolic diseases including type 2 diabetes and immune disorders. Obesity also leads to reduced lifespan and accelerated cellular processes similar to those of aging. On the other hand, aging is accompanied by the accumulation of visceral fat and the metabolic complications associated to obesity. Both obesity and aging have been identified as chronic, low-grade inflammation disorders. The inflammation in aging has been considered as a risk factor for the development of most of age-related diseases, and therefore for morbidity and mortality in the elderly. However, the specific mechanisms leading to inflammation in aging remain largely unknown.

Resolution of inflammation is an active process which involves production of several series of specialized pro-resolving lipid mediators such lipoxins, resolvin, protectins and maresin. The hypothesis of this trial is that the chronic inflammation associated to obesity and aging could be the result of an impaired production of these specialized pro-resolutive lipid mediators, mainly in adipose tissue. On the other hand, the investigators also propose that altered transcriptional pattern might be responsible for the development of the inflammation associated with the pathophysiology of obesity and aging. Therefore the first general aim of the current project will be to characterize the mechanisms involved in the unresolved chronic inflammation that arises during obesity and aging.

Because n-3 PUFAs (polyunsaturated fatty acids) serve as substrates for the synthesis of specialized pro-resolving lipid mediators and are important transcriptional regulators, the investigators propose that dietary supplementation with n-3 PUFAs, alone or in combination with regular physical exercise could promote the resolution of local and systemic inflammation and the subsequent metabolic disorders associated to obesity and aging. A trial in overweight/obese postmenopausal women will be carried out to characterize the potential beneficial effects of regular administration of a DHA-rich dietary supplement and/or a progressive resistance training (PRT) program on weight and fat mass loss, insulin sensitivity, inflammatory markers and gene/miRNA/lipidomic/metabolomic profile in serum and/or adipose tissue. Moreover, changes in gut microbiota will be also addressed.

Eligibility Criteria:
Inclusion Criteria:

* Post-menopausal women
* Age between 55 and 70 years
* Body Mass Index (BMI) between 27.5 and 35 kg/m²
* Weight unchanged (± 3 kg) for the last 3 months
* Overall physical and psychological condition that the investigator believes is in accordance with the overall aim of the study

Exclusion Criteria:

* Use of regular prescription medication: specially statins, antidiabetic drugs, menopausal hormone replacement therapy
* To suffer from any chronic metabolic condition: severe dislipidemia, type 1 or 2 diabetes, hepatic (cirrhosis), renal disease, cardiovascular disease, neuromuscular disease, arthritic disease, pulmonary disease and/or other debilitating diseases
* Food allergies and/or food intolerance expected to come up during the study
* Following special diets (Atkins, vegetarian, etc.) prior three months the start of the study
* Eating disorders
* Surgically treated obesity
* Alcohol or drug abuse