Weight Regulation by the Immune System and the Influence of Thyroid Hormones
St. Vincent's University Hospital, Elm Park, Dublin, Ireland; University College Dublin, Ireland
Keynote Message
Obesity is now accepted to be a most important condition in humans and pets. It is linked to a range of chronic diseases including cancer, dementia, and diabetes. The reality is that weight gained is 90% irreversible for 90% of people who successfully adopt lifestyle change, pharmacotherapy may increase this to 20% weight reduction in 20% of individuals, and gastric surgery enables up to 30% weight loss.
There is a recognition that the simple "energy in - energy out" equation is no longer fit for purpose in understanding weight regulation. The explosion in extreme obesity and childhood obesity demands a fuller understanding of just how the body controls weight - and in particular defends against weight loss. Each individual handles a kilocalorie differently thanks to among other factors, the gut microbiome and that individual's rate of energy burn. It is now emerging that the innate immune system is a fundamental and dynamic player in the regulation of thermogenesis.
This talk will outline the way that the immune system regulates weight and will show how hormones regulate this. This is relevant for a range of hormones that are known to regulate weight including thyroid hormone.
Key References
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2. Lynch L, Nowak M, Varghese B, Clark J, Hogan AE, Toxavidis V, Balk SP, O'Shea D, O'Farrelly C, Exley MA. Adipose tissue invariant NKT cells protect against diet-induced obesity and metabolic disorder through regulatory cytokine production. Immunity. 2012;37(3):574–87. PMID: 22981538
3. Hogan AE, Tobin AM, Ahern T, Corrigan MA, Gaoatswe G, Jackson R, O'Reilly V, Lynch L, Doherty DG, Moynagh PN, Kirby B, O'Connell J, O'Shea D. Glucagon-like peptide-1 (GLP-1) and the regulation of human invariant natural killer T cells: lessons from obesity, diabetes and psoriasis. Diabetologia. 2011;54(11):2745–54.