THE FAT MONSTER

PLEASE NOTE: bradpriester@mouthplague.com, “CONTACT US”, “Leave a Reply”, and the log in function HAVE NOT BEEN ACTIVATED. IF YOU HAVE ANY COMMENTS, PLEASE EMAIL THEM TO THE AUTHOR AT bpriester@aol.com

Excess fat is evil. Once the fat monster starts growing, it begins spewing a wicked venom of disease-causing molecules. All the fat monster wants is to grow as big as it can and to wreak havoc on other parts of the body.

LEPTIN

When I was in med school in the late 80′s, we had simple thoughts about fat. Fat was just an energy warehouse. Unsightly excess fat was just a result of the problem, not an integral part of the problem. That all changed in 1994 when Jeffrey Friedman discovered leptin at Rockefeller University.

The discovery of leptin as the first known hormone secreted by fat cells (adipocytes) launched an aggressive exploration for additional adipocyte secreted molecules that influence other parts of the body. Unfortunately, we have learned this influence becomes quite sinister when excess fat is present.

Stating the biology of leptin in a simple fashion: the more fat you have, the more leptin your fat should be making. Leptin works at the level of the hypothalamus to suppress appetite and increase energy expenditure. Unfortunately, some people do not make enough leptin or they develop leptin resistance. There are also many feedback loops with signalling molecules from other tissues in the body and with activities other than eating. So, there is nothing simple about the biology of leptin and there are many scientific labs pursuing the answers to the leptin puzzle.

ADIPONECTIN

The discovery of leptin was followed by the discovery of adiponectin in 1996 by Yuji Matsuzawa. Secreted by adipose tissue, adiponectin is primarily involved in the regulation of glucose and fatty acid metabolism. Unlike leptin, adiponectin’s presence in blood in inversely proportional to the amount of body fat. Adiponectin works to suppress obesity, insulin resistance, hypertension, atherosclerosis, inflammation, stroke, type II diabetes, and other conditions associated with the metabolic syndrome.

Dr. Matsuzawa feels that adiponectin is the centerpiece of pro-health molecules in our bloodstream. He coined the term “hypoadiponectinemia” to describe pathologic situations in which there is not enough adiponectin circulating. Primary hypoadiponectinemia describes low levels due to genetic factors. Secondary hypoadiponectinemia describes low levels due to excess visceral fat.

In good health, adiponectin is unique in that it exists in the blood stream at a much higher concentration than other hormones and cytokines. It’s multimeric structure (single adiponectin molecules clump together like legos to form larger structures) is thought to help enable attachment to damaged endothelial walls where it helps the healing process.

RESISTIN

Discovered in 2001 by Mitchell Lazar at the University of Pennsylvania, resistin is secreted by adipose tissue and is associated with insulin resistance and inflammation. However, there is ongoing controversy regarding it’s true biological role.

INFLAMMATORY MOLECULES

In addition to the adipocyte secreted homones described above, adipose tissue produces an array of non-tissue specific inflammatory molecules. Dr. Matsuzawa was the first to coin the phrase “adipocytokines” for these inflammatory molecules secreted by body fat. “Adipokine” is now a common expression in the scientific literature referring to all molecules secreted by adipocytes. Dr. Matsuzawa found that visceral fat is a more active secreter of disease-promoting adipokines than subcutaneous fat.

Plasminogen activator type 1 (PAI-1), heparin binding epidermal factor-like growth factor, and tumor necrosis factor-alpha are three of the main adipocytokines and are associated with clotting disorders, atherosclerosis, and insulin resistance.

OTHER ADIPOKINES

Visfatin
Adipsin
Apelin
Agouti Signalling Protein
Acylation Stimulating Protein
Nitric Oxide
Renin
Angiotensin II
Interleukins-1β, 6, 8, 10
Monocyte chemoattractant protein-1
Migration inhibitory factor
Prostaglandin E2
Hepatocyte growth factor
Vascular endothelial growth factor
Nerve growth factor
Insulin-like growth factor-1

MORE TO COME!!!

Leave a Reply

You must be logged in to post a comment.