Adipose Tissue II EDDIE SMITHLEAH WAGNER LEAH SANDERSJONATHAN GRIMWOOD FWS

How is adipose stored?  Energy ingested as fat beyond what is needed by the body is stored in adipose tissue.  Carbohydrates and proteins can be converted to fat  Carbohydrates are stored in the form of glycogen in the liver and muscle  Carbohydrates can also be converted to triglycerides in the liver, then transferred to adipose tissue for storage

How does it get there to be stored?  When fat is ingested via the diet:  Emulsified by bile acids in the intestine  Fat and cholesterol packaged into chylomicrons  Chylomicrons pass into the lymph system and then into the blood  Enzymes (lipoproten lipase) break the fats into fatty acids  Enzyme activity depends on levels of insulin in the body  High insulin: lipases are highly active  Low insulin: lipases are inactive  Adipose, muscle and liver cells take up triglycerides from chylomicrons  Chylomicron gradually becomes smaller and is absorbed by the liver

How does it get there to be stored?  When fat is made in the liver:  Fat, in the form of triglycerides or cholesterol, is exported by a lipoprotein  Very Low Density Lipoprotein (VLDL): mainly composed of fat  VLDL circulates through blood and triglycerides are removed as fat moves into adipose tissue  As it gets smaller, it becomes LDL  Low Density Lipoprotein (LDL): high amount of cholesterol  With high amounts of LDL in the blood, individuals are at a higher risk for vascular diseases as it forms plaque and foam cells in the arteries.

How does it get there to be stored?  High Density Lipoprotein (HDL): moves cholesterol from tissues to liver  Once in the liver, the cholesterol becomes part of the ‘cholesterol pool in the liver’

Cholesterol Levels

How is adipose formed and grown?  When calories in > calories out  Adipose cells grow similar to other cells in the body  Hyperplasia: increase in the number of adipose cells  Hypertrophy : increase in the size of adipose cells  Once new adipose cells are formed, they remain throughout life and can only reduce in size.  Genetics and diet effect the contributions of these two mechanisms

How do you adjust adipose?  Fat is a required nutrient for optimal health  Intake should not excess 35% of total calories  Know your fats: saturated vs unsaturated

How do you adjust adipose?  Saturated fats:  Solid at room temperature  Come from animal sources (butter, milk, meat)  Consumed in moderation, increased levels create high cholesterol levels  Unsaturated fats:  Monounsaturated and polyunsaturated  Liquid at room temperature  Come from plant sources (vegetable & olive oil, avocado, nuts)  Benneficial to health, helps to lower cholesterol levels

How do you adjust adipose? A third group of fatty acids to note:  Trans fatty acids:  When unsaturated fats are changed making it solid  Commonly found in processed foods  Similar to saturated fats

How do you adjust adipose?  To maintain a healthy weight:  Eat a balanced diet  Appropriate amounts of carbohydrates, fat, and protein  Do not eat excessively  Most people require 1,500-2,000 calories a day  Exercise regularly