Hunger And Obesity Flashcards
What are some factors that decrease appetite and remove the sensation of hunger?
Insulin-dependent glucose utilization by the hypothalamus. Insulin. Diet-induced thermogenesis. Presence of food in the GIT.
What are the 2 groups of functionally distinct neurons?
Anorexigenic (appetite-suppressing) - secrete POMC derived peptides
Orexigenic (appetite-promoting) - secrete agouti-related peptide or NPY
List some GI Peptide and their functions?
CCK acts on the brain and enhances satiety. Is inhibited by somatostatin.
Ghrelin is secreted by the stomach and acts on the brain to increase food intake.
Peptide YY slows peristalsis in response to food.
Neuropeptide Y acts on the brain to increase food intake.
Leptin is expressed by adipoctyes and is involved in long-term energy expenditure.
Nasfatin 1 is a regulator of feeding behaviour and energy homeostasis. It produces an anorexigenic effect.
What is the difference between anorexia amd bulimia nervosa?
Anorexia - morbid fear of being fat. Drastically reduced food intake. Complications: low BP, hypoglycaemia and amenorrhea.
Bulimia - binge eating, self-induced vomiting. More psychological problem rather than biological.
How do we assess weight
Medical history is important. Age of onset, family history, lifestyle behaviours, perform screening test.
What is Prader-Willi syndrome?
Characterised by hypotonia, feeding difficulties in infants, developmental delay, hyperphagia, hypogonadotropic hypogonadism. Recombinant GH decreases body fat and increases linear growth.
What is the MoA of phentermine and benzphentamine?
They reduce food intake.
It mimics NE, blocks NE re-uptake, supresses food intake. Delays onset of a meal or produce early satiety.
What is the Side effect of these drugs?
Insomnia, dry mouth, constipation, increased blood pressure.
What is the MoA of Locaserin and what is its status?
5HT2c receptor agonist. Its MoA is that it increases POMC levels in the hypothalamus to produce an anorexigenic effect. It is not used because of the risk that it can cause cancers.
What is the MoA of Orlistat?
It irreversibly inhibits serine residues, preventing the breakdown of dietary fat into fatty acids and glycerol. Prevents the absorption of fats. Therefore, it reduces leptin levels and BP. Delays gastic emptying and secretion. Also decreases the absorption of fat-soluble vitamins.
What are the adverse effects of orlistat?
Abdominal cramps, faecal incontinence, flatus with discharge.
What is the difference between malabsorptive and restrictive bariatric surgery?
Malabsorptive limits the amount of nutrients the body absorbs by bypassing a portion of the small intestine.
Restrictive bariatric surgery reduces the size of the stomach.
