Obesity is a world wide epidemic; it is becoming more usual to be
overweight or obese than to be normal weight.
Obesity increases the risk of an extensive range of diseases such as
cardiovascular disease,
diabetes mellitus type 2,
hypertension, depression and some types of
cancer. Adipose tissue is more than a storage organ for surplus energy - it is also a setting for complex metabolic processes and adipose tissue releases substances that interact with other parts of the body to influence several systems including food intake and energy metabolism. The
endocannabinoid system (ECS) is one of the signalling systems that control feeding behaviour. The ECS is implicated in many functions, such as
pain, memory, addiction,
inflammation, and feeding, and could be considered a stress recovery system. It also seems to integrate nutrient intake, metabolism and storage maintaining homeostatic balance. The ECS is a recently discovered system, and research indicates hyperactivity in
obesity. The aim of this thesis is to elaborate on the relationships of this widespread system and its elements in adipose tissue in
obesity. Study I is a 4 weeks rat intervention study to investigate whether weight independent effect of
Rimonabant treatment exists. We found that food intake-tolerance development could be circumvented by cyclic administration of
Rimonabant and implications of weight independent effects of treatment. Study II is a cross-sectional study to establish the expression of
cannabinoid receptor 1 from various adipose tissue depots of lean and obese persons. In this study we conclude, that the subcutaneous adipose tissue express more CBR1 than the visceral depot in lean, but comparable levels in obese. Study III is
a 10 weeks human intervention study to asses the effects on the ECS of 10%
weight loss. We found reduction in the ECS in
obesity that normalised with
weight loss. Our results clearly show the presence of all the components of the ECS in human adipose tissue, and suggest that the ECS is reduced in adipose tissue in
obesity. Our results do not support the hypothesis of hyperactivity of the ECS in human
obesity. Possible future treatment of
obesity with CBR1 antagonist could involve cyclic treatment of specific peripheral compounds.