Overweight and obesity due to excess body fat have reached epidemic levels in the United States. These conditions contribute to a growing number of cases of diabetes, heart disease, arthritis and other serious health conditions, which can lead to avoidable disability and early death.

However, a certain amount of body fat is necessary for proper body functioning. Fat, also called adipose tissue, serves as a reserve of stored energy that the body can use during periods of reduced calorie intake. Fat provides the building blocks for certain hormones, and it releases substances that are important in energy regulation, immune responses and other body functions. Fat serves as insulation to help maintain body temperature, and it stores fat-soluble nutrients, such as vitamins A, D, E and K.

When developing new drugs, scientists must keep in mind that most drugs do not spread evenly throughout the body. Drugs that dissolve in water (water-soluble drugs) tend to stay within the blood and the fluid that surrounds cells. Drugs that dissolve in fat (fat-soluble drugs) tend to concentrate in fatty tissues.

Adipose Tissue on a Chip  

An NIH-supported team of researchers at the University of California, Berkeley, are developing a 3-D chip system containing human adipose tissue for screening potential new drugs for effectiveness and toxic side effects. The chip could be linked with other organs on chips to create a holistic view of how a compound is processed by and affects other major body systems.

Looking Ahead

The adipose tissue on a chip could be used to test experimental drugs and might provide data to accelerate the drug approval process and make new treatments available sooner to patients. The ability to screen potential drugs accurately in this model would be a major advance over the use of animal models and cell-based systems, which can fail to predict dangerous reactions.

The chip device also might shed light on how fat functions in the body, leading to new interventions for obesity-related diseases, including diabetes, heart disease, arthritis, metabolic diseases and other serious health conditions.